AXT INC, 10-K filed on 3/15/2024
Annual Report
v3.24.0.1
Document and Entity Information - USD ($)
 12 Months Ended
Dec. 31, 2023
Mar. 01, 2024
Jun. 30, 2023
Document And Entity Information      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2023    
Document Transition Report false    
Entity File Number 000-24085    
Entity Registrant Name AXT INC    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 94-3031310    
Entity Address, Address Line One 4281 Technology Drive    
Entity Address, City or Town Fremont    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94538    
City Area Code 510    
Local Phone Number 438-4700    
Title of 12(b) Security Common Stock, $0.001 par value    
Trading Symbol AXTI    
Security Exchange Name NASDAQ    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
ICFR Auditor Attestation Flag true    
Entity Filer Category Accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company false    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   44,248,248  
Entity Public Float     $ 117,469,192
Auditor Name BPM LLP    
Auditor Firm ID 207    
Auditor Location San Jose, California    
Entity Central Index Key 0001051627    
Current Fiscal Year End Date --12-31    
Document Fiscal Year Focus 2023    
Document Fiscal Period Focus FY    
Amendment Flag false    
v3.24.0.1
CONSOLIDATED BALANCE SHEETS - USD ($)
Dec. 31, 2023
Dec. 31, 2022
Current assets:    
Cash and cash equivalents $ 37,752,000 $ 34,948,000
Restricted cash 12,362,000 6,400,000
Short-term investments 2,140,000 9,339,000
Accounts receivable, net of allowances for credit losses of $579 and $307 as of December 31, 2023 and December 31, 2022 19,256,000 29,252,000
Inventories 86,503,000 89,629,000
Prepaid expenses and other current assets 12,643,000 13,977,000
Total current assets 170,656,000 183,545,000
Long-term investments   2,118,000
Property, plant and equipment, net 166,348,000 161,017,000
Operating lease right-of-use assets 2,799,000 1,761,000
Other assets 18,898,000 21,631,000
Total assets 358,701,000 370,072,000
Current liabilities:    
Accounts payable 9,617,000 10,084,000
Accrued liabilities 19,019,000 18,164,000
Bank loans 52,921,000 47,078,000
Total current liabilities 81,557,000 75,326,000
Noncurrent operating lease liabilities 2,351,000 1,322,000
Other long-term liabilities 5,647,000 3,678,000
Total liabilities 89,555,000 80,326,000
Commitments and contingencies (Note 16)
Redeemable noncontrolling interests (Note 18) 41,663,000 44,846,000
Stockholders' equity:    
Preferred stock Series A, $0.001 par value; 2,000 shares authorized; 883 shares issued and outstanding as of December 31, 2023 and December 31, 2022 (Liquidation preference of $7,875 and $7,699 as of December 31, 2023 and December 31, 2022) 3,532,000 3,532,000
Common stock, $0.001 par value; 70,000 shares authorized; 44,239 and 43,554 shares issued and outstanding as of December 31, 2023 and December 31, 2022 44,000 44,000
Additional paid-in capital 238,452,000 235,308,000
Accumulated deficit (32,040,000) (14,159,000)
Accumulated other comprehensive loss (5,999,000) (3,118,000)
Total AXT, Inc. stockholders' equity 203,989,000 221,607,000
Noncontrolling interests 23,494,000 23,293,000
Total stockholders' equity 227,483,000 244,900,000
Total liabilities, redeemable noncontrolling interests and stockholders' equity $ 358,701,000 $ 370,072,000
v3.24.0.1
CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Current assets:    
Accounts receivable, allowances for doubtful accounts $ 579 $ 307
Stockholders' equity:    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares issued (in shares) 883,000 883,000
Preferred stock, shares outstanding (in shares) 883,000 883,000
Preferred stock, liquidation preference $ 7,875 $ 7,699
Common stock, par value (in dollars per share) $ 0.001 $ 0.001
Common stock, shares authorized (in shares) 70,000,000 70,000,000
Common stock, shares issued (in shares) 44,239,000 44,239,000
Common stock, shares outstanding (in shares) 43,554,000 43,554,000
Series A Preferred Stock    
Stockholders' equity:    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares authorized (in shares) 2,000,000 2,000,000
Preferred stock, shares issued (in shares) 883,000 883,000
Preferred stock, shares outstanding (in shares) 883,000 883,000
v3.24.0.1
CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)
shares in Thousands, $ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
CONSOLIDATED STATEMENTS OF OPERATIONS      
Revenue $ 75,795 $ 141,118 $ 137,393
Cost of revenue 62,477 88,997 89,979
Gross profit 13,318 52,121 47,414
Operating expenses:      
Selling, general and administrative 22,806 25,654 24,189
Research and development 12,081 13,913 10,328
Total operating expenses 34,887 39,567 34,517
Income (loss) from operations (21,569) 12,554 12,897
Interest expense, net (1,527) (1,071) (213)
Equity in income of unconsolidated joint ventures 1,884 5,957 4,409
Other income, net 2,179 3,487 509
Income (loss) before provision for income taxes (19,033) 20,927 17,602
Provision for income taxes 160 2,185 1,093
Net income (loss) (19,193) 18,742 16,509
Less: Net (income) loss attributable to noncontrolling interests and redeemable noncontrolling interests 1,312 (2,931) (1,934)
Net income (loss) attributable to AXT, Inc. $ (17,881) $ 15,811 $ 14,575
Net income (loss) attributable to AXT, Inc. per common share:      
Basic $ (0.42) $ 0.37 $ 0.35
Diluted $ (0.42) $ 0.37 $ 0.34
Weighted-average number of common shares outstanding:      
Basic 42,643 42,104 41,367
Diluted 42,643 42,715 42,720
v3.24.0.1
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)      
Net income (loss) $ (19,193) $ 18,742 $ 16,509
Other comprehensive income (loss), net of tax:      
Change in foreign currency translation gain (loss), net of tax (3,818) (10,994) 3,719
Change in unrealized gain (loss) on available-for-sale debt investments, net of tax 283 (238) (68)
Total other comprehensive income (loss), net of tax (3,535) (11,232) 3,651
Comprehensive income (loss) attributable to AXT, Inc. (22,728) 7,510 20,160
Less: Comprehensive (income) loss attributable to noncontrolling interests and redeemable noncontrolling interests 1,965 (1,117) (2,492)
Comprehensive income (loss) attributable to AXT, Inc. $ (20,763) $ 6,393 $ 17,668
v3.24.0.1
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)
shares in Thousands, $ in Thousands
Preferred Stock
Common Stock
Additional Paid-In Capital
Accumulated Deficit
Accumulated Other Comprehensive Income (Loss)
AXT, Inc. Stockholders' Equity
Noncontrolling Interests
Total
Balance, beginning of period at Dec. 31, 2020 $ 3,532 $ 42 $ 230,381 $ (44,545) $ 3,209 $ 192,619 $ 15,350 $ 207,969
Balance (in shares) at Dec. 31, 2020 883 41,967            
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Common stock options exercised   $ 1 1,669     1,670   1,670
Common stock options exercised (in shares)   507            
Formation of new subsidiary with noncontrolling interests     (262)     (262) 1,413 1,151
Transfer of subsidiary with noncontrolling interests     (1,229)     (1,229) 1,229  
Restricted stock awards canceled   (14)            
Stock-based compensation     4,519     4,519   4,519
Issuance of common stock in the form of restricted stock (in shares)   426            
Purchase of subsidiary shares from noncontrolling interests     (2,691)     (2,691) (1,039) (3,730)
Transfer of subsidiary with redeemable noncontrolling interest     (1,241)     (1,241)   (1,241)
Noncontrolling interest portion of Tongmei stock-based compensation     (62)     (62) 40 (22)
Sale of common stock to employees in connection with the reorganization     538     538   538
Net income (loss)       14,575   14,575 1,045 15,620
Other comprehensive income (loss)         3,093 3,093 279 3,372
Balance, end of period at Dec. 31, 2021 $ 3,532 $ 43 231,622 (29,970) 6,302 211,529 18,317 229,846
Balance (in shares) at Dec. 31, 2021 883 42,886            
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Common stock options exercised   $ 1 517     518   518
Common stock options exercised (in shares)   172            
Restricted stock awards canceled   (91)            
Stock-based compensation     3,273     3,273   3,273
Issuance of common stock in the form of restricted stock (in shares)   587            
Purchase of subsidiary shares from noncontrolling interests     (466)     (466) 2,699 2,233
Noncontrolling interest portion of Tongmei stock-based compensation     100     100 (42) 58
Net income (loss)       15,811   15,811 1,333 17,144
Other comprehensive income (loss)         (9,420) (9,420) (901) (10,321)
Investment in subsidiary from noncontrolling interest             1,887 1,887
Investment in subsidiary with redeemable noncontrolling interest     (471)     (471)   (471)
Tongmei stock-based compensation     733     733   733
Balance, end of period at Dec. 31, 2022 $ 3,532 $ 44 235,308 (14,159) (3,118) 221,607 23,293 244,900
Balance (in shares) at Dec. 31, 2022 883 43,554            
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Common stock options exercised     10     10   10
Common stock options exercised (in shares)   4            
Restricted stock awards canceled   (23)            
Stock-based compensation     2,779     2,779   2,779
Issuance of common stock in the form of restricted stock (in shares)   704            
Purchase of subsidiary shares from noncontrolling interests     (153)     (153) 861 708
Noncontrolling interest portion of Tongmei stock-based compensation     (98)     (98) 55 (43)
Net income (loss)       (17,881)   (17,881) (391) (18,272)
Other comprehensive income (loss)         (2,881) (2,881) (324) (3,205)
Investment in subsidiary with redeemable noncontrolling interest     (155)     (155)   (155)
Tongmei stock-based compensation     761     761   761
Balance, end of period at Dec. 31, 2023 $ 3,532 $ 44 $ 238,452 $ (32,040) $ (5,999) $ 203,989 $ 23,494 $ 227,483
Balance (in shares) at Dec. 31, 2023 883 44,239            
v3.24.0.1
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Cash flows from operating activities:      
Net income (loss) $ (19,193) $ 18,742 $ 16,509
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:      
Depreciation and amortization 8,722 8,119 7,078
Amortization of marketable securities premium 18 58 68
Stock-based compensation 3,540 4,006 4,519
Provision for credit losses 272 (177) 87
Loss on sale of equity investment 166    
(Gain) Loss on disposal of equipment 21 (85) (8)
Return of equity method investments (dividends) 4,316 1,608 774
Equity in income of unconsolidated joint ventures (2,050) (5,957) (4,409)
Deferred tax assets 553 104 2,340
Changes in operating assets and liabilities:      
Accounts receivable 9,306 4,535 (9,748)
Inventories 1,073 (31,412) (12,401)
Prepaid expenses and other current assets (652) (3,486) (798)
Other assets 419 (471) (6,283)
Accounts payable (162) (5,519) 3,563
Accrued liabilities (1,897) (2,127) (3,445)
Other long-term liabilities (1,049) 3,297 (1,151)
Net cash provided by (used in) operating activities 3,403 (8,765) (3,305)
Cash flows from investing activities:      
Purchases of property, plant and equipment (10,475) (28,465) (29,645)
Purchases of available-for-sale debt securities   (2,158) (9,645)
Proceeds from sales and maturities of available-for-sale debt securities 9,582 5,400 480
Proceeds from sales of equity securities - 15% of Jia Mei 827    
Investments in non-marketable equity investments (2,538)    
Net cash used in investing activities (2,604) (25,223) (38,810)
Cash flows from financing activities:      
Proceeds from common stock options exercised 10 518 1,670
Proceeds from sale of subsidiary shares to noncontrolling interests     538
Proceeds from short-term bank loans 56,470 53,078 20,543
Proceeds from long-term loan from noncontrolling interest     1,834
Payments on short-term bank loans (49,210) (17,798) (19,066)
Proceeds from capital increase in subsidiary shares from noncontrolling interests 708 2,233  
Proceeds from long-term loan 635    
Formation of new subsidiary with noncontrolling interests     1,283
Proceeds from issuance of Tongmei's common stock to redeemable noncontrolling interests, net of costs     (1,077)
Net cash provided by financing activities 8,613 38,031 5,725
Effect of exchange rate changes on cash and cash equivalents, and restricted cash (646) 542 551
Net increase (decrease) in cash and cash equivalents, and restricted cash 8,766 4,585 (35,839)
Cash, restricted cash and cash equivalents at the beginning of the year 41,348 36,763 72,602
Cash, restricted cash and cash equivalents at the end of the period 50,114 41,348 36,763
Supplemental disclosures:      
Income taxes paid, net of refunds 686 1,692 3,177
Interest expense paid 1,564    
Supplemental disclosure of non-cash flow information:      
Loan proceeds received by notes receivable 1,481    
Notes receivables paid to purchase fixed assets 4,170 6,835  
Non-cash consideration received from sale of DongFang 585    
Conversion of related party borrowings to Additional Paid-in Capital   1,887  
Investment in subsidiary shares from noncontrolling interest 308 937  
Bank loan proceeds paid directly to a third-party vendor, included in accounts payable   474  
Sales of land and building to unconsolidated joint venture   976  
Consideration payable in connection with construction in progress, included in accrued liabilities $ 6,574 $ 4,135 $ 2,974
v3.24.0.1
CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)
 12 Months Ended
Dec. 31, 2023
CONSOLIDATED STATEMENTS OF CASH FLOWS  
Percentage of equity interest sold 15.00%
v3.24.0.1
The Company and Summary of Significant Accounting Policies
 12 Months Ended
Dec. 31, 2023
The Company and Summary of Significant Accounting Policies  
The Company and Summary of Significant Accounting Policies

Note 1. The Company and Summary of Significant Accounting Policies

The Company

AXT, Inc. (“AXT”, “the Company”, “we,” “us,” and “our” refer to AXT, Inc. and its consolidated subsidiaries) is a worldwide materials science company that develops and produces high-performance compound and single element semiconductor substrates, also known as wafers. Our consolidated subsidiaries produce and sell certain raw materials some of which are used in our substrate manufacturing process and some of which are sold to other companies.

​

Our substrate wafers are used when a typical silicon substrate wafer cannot meet the conductive requirements of a semiconductor or optoelectronic device. The dominant substrates used in producing semiconductor chips and other electronic circuits are made from silicon. However, certain chips may become too hot or perform their function too slowly if silicon is used as the base material. In addition, optoelectronic applications, such as LED lighting and chip-based lasers, do not use silicon substrates because they require a wave form frequency that cannot be achieved using silicon. Alternative or specialty materials are used to replace silicon as the preferred base in these situations. Our wafers provide such alternative or specialty materials. We do not design or manufacture the chips. We add value by researching, developing and producing the specialty material wafers. We have two product lines: specialty material substrates and raw materials integral to these substrates. In 2023, our substrate product group generated 63% of our revenue and raw materials product group generated 37%. Our compound substrates combine indium with phosphorous (indium phosphide: InP) or gallium with arsenic (gallium arsenide: GaAs). Our single element substrates are made from germanium (Ge).

Our raw materials include purified gallium, InP based material and pBN crucibles. We use purified gallium in producing our GaAs substrates and also sell purified gallium in the open market to other companies for use in magnetic materials, high temperature thermometers and growing single crystal ingots including gallium arsenide, gallium nitride, gallium antimonite, gallium phosphide and other materials and alloys. Pyrolytic boron nitride (pBN) crucibles are used in the high temperature (typically in the range 500 C to 1,500 C) growth process of single crystal ingots and epitaxial layer growth in MBE reactors. We use these pBN crucibles in our own ingot growth processes and also sell them in the open market to other companies.

Principles of Consolidation

The consolidated financial statements include the accounts of AXT, and our consolidated subsidiaries, Beijing Tongmei Xtal Technology Co., Ltd. (“Tongmei”), AXT-Tongmei, Inc. (“AXT-Tongmei”), Baoding Tongmei Xtal Technology Co., Ltd. (“Baoding Tongmei”), ChaoYang Tongmei Xtal Technology Co., Ltd. (“ChaoYang Tongmei”), ChaoYang LiMei Semiconductor Technology Co., Ltd. (“ChaoYang LiMei”), ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd. (“ChaoYang XinMei”), Nanjing JinMei Gallium Co., Ltd. (“JinMei”), ChaoYang JinMei Gallium Ltd. (“ChaoYang JinMei”), ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd. (“ChaoYang ShuoMei”), MaAnShan JinMei Gallium Ltd., (“MaAnShan JinMei”) and Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd. (“BoYu”). Baoding Tongmei is located in the city of Dingxing, China. Each of ChaoYang Tongmei and ChaoYang LiMei is located in the city of Kazuo, China. All significant inter-company accounts and transactions have been eliminated. Investments in business entities in which we do not have controlling interests, but have the ability to exercise significant influence over operating and financial policies (generally 20-50% ownership), are accounted for by the equity method. For the years ended 2023 and 2022, we have three and six companies accounted for by the equity method, respectively. For the majority-owned subsidiaries that we consolidate, we reflect the portion we do not own as either noncontrolling interests in stockholder’s equity or as redeemable noncontrolling interests in temporary equity on our consolidated balance sheets and in our consolidated statements of operations.

​

When market conditions are warranted, we intend to construct facilities at the ChaoYang LiMei location to provide us with additional production capacity. For the years ended 2023 and 2022, expenses associated with ChaoYang LiMei had a de minimis impact on our consolidated financial statements.

​

In February 2021, Tongmei signed a joint venture agreement with certain investors to fund a new company, ChaoYang XinMei. The agreement called for a total investment of approximately $3.0 million, of which Tongmei would fund approximately $1.8 million for a 58.5 percent ownership of ChaoYang XinMei. In February 2021, the investors completed the initial funding of approximately $1.5 million. Tongmei’s portion of the investment was approximately $0.9 million. In May 2021, the investors completed the funding of the remaining balance of approximately $1.5 million. Tongmei’s portion of the final investment was approximately $0.9 million, for a total investment of approximately $1.8 million for a 58.5 percent ownership of ChaoYang XinMei. In September 2021 and October 2021, ChaoYang XinMei received funding from a minority investor of $0.9 million and $1.0 million, respectively. In December 2021 and January 2022, ChaoYang XinMei received funding from Tongmei of $1.4 million and $1.4 million, respectively. In January 2022, the China local government certified this additional funding in ChaoYang XinMei as an equity investment. Tongmei’s ownership remained at 58.5% after these equity investments. In April 2022, Tongmei entered into a capital increase agreement (the “Capital Increase Agreement”) with minority investors to further invest $4.5 million in ChaoYang XinMei. Tongmei’s portion of the investment was approximately $2.6 million, of which $1.1 million was invested in April 2022 and $0.8 million was invested in May 2022. The minority investors’ portion of the investment was approximately $1.9 million, of which $0.7 million was invested in April 2022 and $0.6 million was invested in May 2022. As a result, noncontrolling interests increased $1.4 million and redeemable noncontrolling interests increased $0.1 million. Tongmei’s ownership remained at 58.5% after the April 2022 and May 2022 equity investments. In July 2022, Tongmei and the minority investors further invested $0.8 million and $0.6 million in ChaoYang XinMei, respectively. This completed the investment obligations under the Capital Increase Agreement. As a result, noncontrolling interests increased $610,000 and redeemable noncontrolling interests increased $57,000. Tongmei’s ownership remained at 58.5% after the July 2022 equity investment.

​

In April 2022, ChaoYang JinMei signed a joint venture agreement with a certain investor to fund a new company, ChaoYang ShuoMei, our consolidated subsidiary. The agreement calls for a total investment of approximately $4.4 million, of which ChaoYang JinMei will fund approximately $3.3 million for a 75 percent ownership of ChaoYang ShuoMei. In July and August 2022, ChaoYang JinMei completed the initial funding of $1.0 million in ChaoYang ShuoMei. In August 2022, the investor invested $334,000 in ChaoYang ShuoMei. As a result, noncontrolling interests increased $406,000 and redeemable noncontrolling interests increased $73,000. In January 2023, ChaoYang ShuoMei received $0.5 million in funding from ChaoYang JinMei and $0.2 million in funding from one of the minority investors. As a result, noncontrolling interests increased $0.2 million and redeemable noncontrolling interests increased $36,000. In May 2023, ChaoYang ShuoMei received $1.0 million in funding from ChaoYang JinMei and $0.3 million in funding from one of the minority investors. As a result, noncontrolling interests increased $0.4 million and redeemable noncontrolling interests increased $75,000. In August 2023, ChaoYang ShuoMei received $0.6 million in funding from ChaoYang JinMei and $0.2 million in funding from one of the minority investors. As a result, noncontrolling interests increased $0.2 million and redeemable noncontrolling interests increased $44,000. ChaoYang JinMei has completed its investment obligations under the ChaoYang ShuoMei Joint Venture Agreement. ChaoYang JinMei’s ownership of ChaoYang ShuoMei remained at 75% after these equity investments.

​

In April 2022, Tongmei signed a joint venture agreement with certain investors to fund a new company, ChaoYang KaiMei. The agreement called for a total investment of approximately $7.6 million, of which Tongmei would fund approximately $3.0 million for a 40.0 percent ownership of ChaoYang KaiMei. In July 2022, the investors completed the initial funding of approximately $2.2 million. Tongmei’s portion of the investment was approximately $0.9 million. In January 2023, Tongmei made an investment of $0.9 million to ChaoYang KaiMei. In each of July 2023 and August 2023, Tongmei made an investment of approximately $0.6 million in ChaoYang KaiMei. These contributions culminated in the fulfillment of all of Tongmei’s financial obligations under the April 2022 ChaoYang KaiMei Joint Venture Agreement. In September 2023, Tongmei entered into another joint venture agreement with the same group of investors. This new agreement called for additional investment of approximately $5.6 million, with Tongmei committing to fund approximately $2.3 million. In December 2023, Tongmei made its initial additional investment of approximately $0.6 million in ChaoYang KaiMei. Tongmei’s ownership of ChaoYang KaiMei remained at 40% after these equity investments.

​

All activities for MaAnShan JinMei ceased during the first half of 2022 and the subsidiary was subsequently dissolved in May 2022. The dissolution of MaAnShan JinMei had a de minimis impact on the consolidated results.

​

During the quarter ended December 31, 2020, Tongmei entered into two sets of definitive transaction documents, each consisting of a capital increase agreement along with certain supplemental agreements in substantially the same form (collectively, the “Capital Increase Agreements”), with several private equity investors in China.

​

In preparation for Tongmei’s application for a listing of shares in an initial public offering (the “IPO”) on the Shanghai Stock Exchange’s Sci-Tech innovAtion boaRd (the “STAR Market”), in late December 2020, we reorganized our entity structures in China. JinMei and BoYu and its subsidiaries were assigned to Tongmei and effectively merged with Tongmei although they retained their own respective legal entity status and are wholly owned subsidiaries of Tongmei. The 33% minority interest stakeholders of BoYu converted their ownership to a 7.59% minority interest in Tongmei. The 8.5% minority interest stakeholders, employees of JinMei, converted their ownership to a 0.38% minority interest in Tongmei. Further, a number of employees, key managers and contributors purchased a 0.4% minority interest in Tongmei. Additionally, Baoding Tongmei and ChaoYang Tongmei, were assigned to Tongmei as wholly owned subsidiaries. In 2020, the private equity funds (the “Investors”) had transferred approximately $48.1 million of new capital to Tongmei. An additional investment of approximately $1.5 million of new capital was funded in January 2021. Under China regulations these investments must be formally approved by the appropriate government agency and are not deemed to be dilutive until such approval is granted. The government approved the approximately $49 million investment in its entirety on January 25, 2021, at which time the Investors owned a redeemable noncontrolling interest in Tongmei of 7.28%. As of September 30, 2022, Tongmei’s noncontrolling interests and redeemable noncontrolling interests totaled approximately 14.5%. AXT remains the controlling stakeholder of Tongmei and holds a majority of the board of director positions of Tongmei. In June 2021, AXT sold AXT-Tongmei to Tongmei for $1. Since Tongmei is 85.5% owned by AXT, and the transaction was between common interest holders, the transaction was accounted for at net book value and resulted in an increase of $1.2 million to noncontrolling interests and $1.2 million to redeemable noncontrolling interests.

​

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires management to make estimates, judgments and assumptions. We believe that the estimates, judgments, and assumptions upon which management relies are reasonable based on information available at the time that these estimates, judgments, and assumptions are made. These estimates, judgments, and assumptions can affect the reported amounts of assets and liabilities as of the date of the consolidated financial statements as well as the reported amounts of revenues and expenses during the periods presented. To the extent there are material differences between these estimates and actual results, our consolidated financial statements would be affected.

Fair Value of Financial Instruments

The carrying amounts of certain of our financial instruments including cash and cash equivalents, restricted cash, short-term investments and long-term investments, accounts receivable, accounts payable, accrued liabilities and bank loans approximate fair value due to their short maturities. Certain cash equivalents and investments are required to be adjusted to fair value on a recurring basis. See Note 2.

Fair Value of Investments

ASC Topic 820, Fair value measurement (“ASC 820”) establishes three levels of inputs that may be used to measure fair value.

Level 1 instruments represent quoted prices in active markets. Therefore, determining fair value for Level 1 instruments does not require significant management judgment, and the estimation is not difficult.

Level 2 instruments include observable inputs other than Level 1 prices, such as quoted prices for similar instruments in markets with insufficient volume or infrequent transactions (less active markets), issuer bank statements, credit ratings, non-binding market consensus prices that can be corroborated with observable market data, model-derived valuations in which all significant inputs are observable or can be derived principally from or corroborated with observable market data for substantially the full term of the assets or liabilities, or quoted prices for similar assets or liabilities. These Level 2 instruments require more management judgment and subjectivity compared to Level 1 instruments, including:

●Determining which instruments are most comparable to the instrument being priced requires management to identify a sample of similar securities based on the coupon rates, maturity, issuer, credit rating, and instrument type, and subjectively select an individual security or multiple securities that are deemed most similar to the security being priced.
●Determining which model-derived valuations to use in determining fair value requires management judgment. When observable market prices for similar securities or comparable securities are not available, we price our marketable debt instruments using non-binding market consensus prices that are corroborated with observable market data or pricing models, such as discounted cash flow models, with all significant inputs derived from or corroborated with observable market data.

Level 3 instruments include unobservable inputs to the valuation methodology that are significant to the measurement of fair value of assets or liabilities. The determination of fair value for Level 3 instruments requires the most management judgment and subjectivity.

We place short-term foreign currency hedges that are intended to offset the potential cash exposure related to fluctuations in the exchange rate between the United States dollar and Japanese yen. We measure the fair value of these foreign currency hedges at each month end and quarter end using current exchange rates and in accordance with generally accepted accounting principles. At quarter end any foreign currency hedges not settled are netted in “Accrued liabilities” on the consolidated balance sheets and classified as Level 3 assets and liabilities. As of December 31, 2023 and 2022, the net change in fair value from the placement of the hedge to settlement had a de minimis impact to the consolidated results.

Foreign Currency Translation

The functional currency of our Chinese subsidiaries is the renminbi, the local currency of China. Transaction gains and losses resulting from transactions denominated in currencies other than the U.S. dollar or in the functional currencies of our subsidiaries are included in “Other income, net” for the years presented. The transaction gain totaled $0.2 million and $1.6 million for the years ended December 31, 2023 and 2022, respectively. The transaction loss for the year ended December 31, 2021 totaled $434,000. The assets and liabilities of the subsidiaries are translated at the rates of exchange on the balance sheet date. Revenue and expense items are translated at the average rate of exchange for the period. Gains and losses from foreign currency translation are included in “Other comprehensive income (loss)”, net of tax in the consolidated statements of comprehensive income (loss).

Revenue Recognition

We manufacture and sell high-performance compound semiconductor substrates including indium phosphide, gallium arsenide and germanium wafers, and our consolidated subsidiaries sell certain raw materials, including high purity gallium (6N and 7N Ga), pyrolytic boron nitride (pBN) crucibles and boron oxide (B2O3). After we ship our products, there are no remaining obligations or customer acceptance requirements that would preclude revenue recognition. Our products are typically sold pursuant to purchase orders placed by our customers, and our terms and conditions of sale do not require customer acceptance. We account for a contract with a customer when there is a legally enforceable contract, which could be the customer’s purchase order, the rights of the parties are identified, the contract has commercial terms, and collectibility of the contract consideration is probable. The majority of our contracts have a single performance obligation to transfer products and are short term in nature, usually less than six months. Our revenue is measured based on the consideration specified in the contract with each customer in exchange for transferring

products that are generally based upon a negotiated formula, list or fixed price. Revenue is recognized when control of the promised goods is transferred to our customer, which is either upon shipment from our dock, receipt at the customer’s dock, or removal from consignment inventory at the customer’s location, in an amount that reflects the consideration we expect to be entitled to receive in exchange for those goods.

​

We have elected to account for shipping and handling as activities to fulfill the promise to transfer the goods. Shipping and handling fees billed to customers in a sales transaction are recorded as an offset to shipping and handling expenses. Sales taxes and value added taxes in foreign jurisdictions that are collected from customers and remitted to governmental authorities are accounted for on a net basis and, therefore, are excluded from revenue.

​

We do not provide training, installation or commissioning services. We provide for future returns based on historical data, prior experience, current economic trends and changes in customer demand at the time revenue is recognized. We do not recognize any asset associated with the incremental cost of obtaining revenue generating customer contracts. As such, sales commissions are expensed as incurred, given that the expected period of benefit is less than one year.

 

Contract Balances

 

We receive payments from customers based on a billing schedule as established in our contracts. Contract assets are recorded when we have a conditional right to consideration for our completed performance under the contracts. Accounts receivables are recorded when the right to this consideration becomes unconditional. We do not have any material contract assets as of December 31, 2023, or 2022.

​

​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31,

​

​

​

2023

​

2022

​

Contract liabilities

​

$

305

​

$

338

​

During the three and twelve months ended December 31, 2023, the Company recognized $9,000 and $287,000, respectively, of revenue that was included in the contract balances as of December 31, 2022. During the three and twelve months ended December 31, 2022, the Company recognized $22,000 and $760,000 of revenue that was included in the contract balances as of December 31, 2021.

​

​

​

​

​

​

​

​

Disaggregated Revenue

 

In general, revenue disaggregated by product types and geography (See Note 14) is aligned according to the nature and economic characteristics of our business and provides meaningful disaggregation of our results of operations. Since we operate in one segment, all financial segment and product line information can be found in the consolidated financial statements.

 

Practical Expedients and Exemptions

 

We elected to use the following practical expedients: (i) not to adjust the promised amount of consideration for the effects of a significant financing component when we expect, at contract inception, that the period between our transfer of a promised product or service to a customer and when the customer pays for that product or service will be one year or less; (ii) to expense costs as incurred for costs to obtain a contract when the amortization period would have been one year or less; (iii) not to assess whether promised goods or services are performance obligations if they are immaterial in the context of the contract with the customer.

 

In addition, we do not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less.

​

Accounting for Sales and Use Taxes

We record sales taxes collected on sales of our products and for amounts not yet remitted to tax authorities as accrued liabilities on our consolidated balance sheets.

Risks and Concentration of Credit Risk

Our business is very dependent on the semiconductor, lasers and optical industries which can be highly cyclical and experience downturns as a result of economic changes, overcapacity, and technological advancements. Significant technological changes in the industry or customer requirements, or the emergence of competitive products with new capabilities or technologies, could adversely affect our operating results. In addition, a significant portion of our revenues and net income is derived from international sales. Fluctuations of the United States dollar against foreign currencies and changes in local regulatory or economic conditions, particularly in an emerging market such as China, could adversely affect operating results.

We depend on a limited number of suppliers for certain raw materials, components and equipment used in manufacturing our products, including quartz tubing and polishing solutions. We generally purchase these materials through standard purchase orders and not pursuant to long-term supply contracts.

Financial instruments that potentially subject us to concentration of credit risk consist primarily of cash and cash equivalents, investments, and accounts receivable. We invest primarily in money market accounts, certificates of deposit and corporate bonds. The composition and maturities are regularly monitored by management. Such deposits are in excess of the amount of the insurance provided by the federal government on such deposits. We are exposed to credit risks in the event of default by the issuers to the extent of the amount recorded on the consolidated balance sheets.

​

We perform ongoing credit evaluations of our customers’ financial condition, and limit the amount of credit extended when deemed necessary, but generally do not require collateral. The credit risk in our accounts receivable is mitigated by our credit evaluation process and the geographical dispersion of sales transactions. No customer accounted for more than 10% of our accounts receivable as of December 31, 2023 and two customers accounted for more than 10% of our accounts receivable as of December 31, 2022.

No customer represented 10% of our revenue for the year ended December 31, 2023 and 2021. One customer represented 15% of our revenue for the year ended December 31, 2022. Our top five customers, although not the same five customers for each period, represented 25% of our revenue for the year 2023, 34% of our revenue for the year 2022, and 26% of our revenue for the year 2021.

For the year ended December 31, 2023, two third-party customers for the raw materials products from our consolidated subsidiaries accounted for over 10% of the revenue from raw materials sales. For the years ended December 31, 2022 and 2021, one third-party customer for the raw materials products from our consolidated subsidiaries accounted for over 10% of the revenue from raw materials sales. Our subsidiaries and raw material joint ventures are a key strategic benefit for us as they further diversify our sources of revenue.

Cash and Cash Equivalents

We consider investments in highly liquid instruments purchased with an original maturity of three months or less to be cash equivalents. Cash equivalents consist primarily of certificate of deposits. Cash and cash equivalents are stated at cost, which approximates fair value.

Restricted Cash

​

We maintain restricted cash in connection with cash balances temporarily restricted for regular business operations. In May 2022, Tongmei and the Bank of Beijing signed a credit facility for $3.4 million. As a condition of the credit facility we must maintain a time deposit at the Bank of Beijing as collateral, and therefore we placed time deposits of $2.9 million and $1.0 million at the Bank of Beijing in April 2022 and May 2022, respectively. In December 2022, we

placed another time deposit of $2.5 million at the Bank of Beijing as collateral for a bank loan of $2.3 million received by Tongmei in January 2023. In January 2023, our consolidated subsidiary, ChaoYang LiMei, placed a time deposit of $3.0 million at the Bank of China as collateral for a bank loan of $2.9 million received by Tongmei in January 2023. When the May 2022 bank loan under the credit facility matured, we utilized the same time deposit of $3.9 million as collateral for a new bank loan of $3.5 million from the Bank of Beijing in June 2023. Furthermore, during June 2023 and December 2023, time deposits of $1.5 million each were placed at the Bank of Beijing as collateral for two bank loans of $1.4 million each received by Tongmei. Each of the bank loans has a term of 12 months. Therefore, the January 2023 bank loans, the June 2023 bank loans, and the December 2023 bank loan, along with the respective time deposits, are classified as short-term investments in our consolidated balance sheets. The time deposits have been excluded from the Company’s cash and cash equivalents balance. As of December 31, 2023, $12.4 million was included in restricted cash in our consolidated balance sheets.

Short-Term and Long-Term Investments

We classify our investments in marketable securities as available-for-sale debt securities. Short-term and long-term investments are comprised of available-for-sale marketable securities, which consist primarily of certificates of deposit and corporate bonds. These investments are reported at fair value as of the respective balance sheet dates with unrealized gains and losses included in accumulated other comprehensive income (loss) within stockholders’ equity on the consolidated balance sheets. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization is included in “Other income, net” in the consolidated statements of operations. Realized gains and losses and declines in value judged to be other than temporary on available-for-sale securities are also included in “Other income, net” in the consolidated statements of operations. The cost of securities sold is based upon the specific identification method.

Accounts Receivable and Allowance for Credit Losses and Sales Returns

Accounts receivable are recorded at the invoiced amount and are not interest bearing. We review at least quarterly, or when there are changes in credit risks, the likelihood of collection on our accounts receivable balances and provide an allowance for credit losses. We measure the expected credit losses on a collective (pool) basis when similar delinquency status exist. We evaluate receivables from U.S. customers with an emphasis on balances in excess of 90 days and for receivables from customers located outside the U.S. with an emphasis on balances in excess of 120 days and establish a reserve allowance on the receivable balances if needed. The reason for the difference in the evaluation of receivables between foreign and U.S. customers is that U.S. customers have historically made payments in a shorter period of time than foreign customers. Foreign business practices generally require us to allow customer payment terms that are longer than those accepted in the United States.

In accordance with ASC 326-20’s current expected credit loss impairment model, we exercise judgment when determining the adequacy of these reserves as we evaluate historical bad debt trends, general economic conditions in the United States and internationally, and reasonable and supportable forecasts of future economic conditions. Uncollectible receivables are recorded as provision for credit losses when a credit loss is expected through the establishment of an allowance, which would then be written off when all efforts to collect have been exhausted and recoveries are recognized when they are received. As of December 31, 2023 and 2022, our accounts receivable, net balance was $19.3 million and $29.3 million, respectively, which was net of an allowance for credit losses of $579,000 and $307,000 as of December 31, 2023 and 2022, respectively. During 2023, we increased the allowance for credit losses by $272,000. During 2022, we increased the allowance for credit losses by $177,000. If actual uncollectible accounts differ substantially from our estimates, revisions to the estimated allowance for credit losses would be required, which could have a material impact on our financial results for the future periods.

As of December 31, 2023 and 2022, the sales returns reserve (included in accrued liabilities) balance was $39,000 and $112,000, respectively. During 2023, we utilized $39,000 and reduced an additional $34,000 and during 2022, we utilized $112,000 and reserved an additional $176,000.

​

Warranty Reserve

We maintain a warranty reserve based upon our claims experience during the prior twelve months and any pending claims and returns of which we are aware. Warranty costs are accrued at the time revenue is recognized. As of December 31, 2023 and 2022, accrued product warranties totaled $703,000 and $669,000, respectively. The increase in accrued product warranties is primarily attributable to increased claims for quality issues experienced by some of our customers. If actual warranty costs or pending new claims differ substantially from our estimates, revisions to the estimated warranty liability would be required, which could have a material impact on our financial condition and results of operations for future periods.

Inventories

Inventories are stated at the lower of cost (approximated by standard cost) or net realizable value. Cost is determined using the weighted average cost method. Our inventory consists of raw materials as well as finished goods and work-in-process that include material, labor and manufacturing overhead costs. We routinely evaluate the levels of our inventory in light of current market conditions in order to identify excess and obsolete inventory, and we provide a reserve for certain inventories to their estimated net realizable value based upon the age and quality of the product and the projections for sale of the completed products. When a reserve is recorded, a new lower cost basis for that inventory is established and subsequent changes in facts and circumstances do not result in the restoration or increase in the new cost basis.

Property, Plant and Equipment

Property, plant and equipment are stated at cost less accumulated depreciation computed using the straight-line method over the estimated economic lives of the assets, which vary from 1 to 39.5 years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life or the term of the lease. We generally depreciate computer, software, office equipment, furniture and fixtures over 3 to 5 years, machinery and equipment over 1 to 20 years, automobiles over 5 to 10 years, leasehold and building improvements over 10 years, or the lease term if shorter, and buildings over 39.5 years. Repairs and maintenance costs are expensed as incurred.

Impairment of Long-Lived Assets

We evaluate property, plant and equipment and intangible assets for impairment. When events and circumstances indicate that long-lived assets may be impaired, we compare the carrying value of the long-lived assets to the projection of future undiscounted cash flows attributable to these assets. In the event that the carrying value exceeds the future undiscounted cash flows, we record an impairment charge against income equal to the excess of the carrying value over the assets’ fair value. Fair values are determined based on quoted market values, discounted cash flows or internal and external appraisals, as applicable. We did not recognize any impairment charges of long-lived assets in 2023, 2022 and 2021.

Impairment of Investments

All available-for-sale debt securities are periodically reviewed for impairment. An investment is considered to be impaired when its fair value is less than its amortized cost basis and it is more likely than not that we will be required to sell the impaired security before recovery of its amortized cost basis. Factors considered in determining whether a loss is temporary include the magnitude of the decline in market value, the length of time the market value has been below cost (or adjusted cost), credit quality, and our ability and intent to hold the securities for a period of time sufficient to allow for any anticipated recovery in market value.

We also invest in equity instruments of privately held companies in China for business and strategic purposes. Investments in our unconsolidated joint venture companies are classified as other assets and accounted for under either the equity or fair value method, depending on whether we have the ability to exercise significant influence over their operations or financial decisions. We monitor our investments for impairment and record reductions in carrying value when events or changes in circumstances indicate that the carrying value may not be recoverable. Determination of impairment is highly

subjective and is based on a number of factors, including an assessment of the strength of each company’s management, the length of time and extent to which the fair value has been less than our cost basis, the financial condition and near-term prospects of the subsidiary, fundamental changes to the business prospects of the Company, share prices of subsequent offerings, and our intent and ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in our carrying value. We estimate fair value of our fair value method investments considering available information such as pricing in recent rounds of financing, current cash positions, earnings (loss) and cash flow forecasts, recent operational performance, and any other readily available market data.

For the year ended December 31, 2023, one of our PRC joint ventures assessed one of its equity investments was fully impaired. For the year ended December 31, 2023, we divested our equity investment in a PRC joint venture. The impairment and divestiture resulted in a total of $1.9 million in impairment charges in our financial results. There were no impairment charges during the year ended December 31, 2022.

Segment Reporting

We operate in one segment for the design, development, manufacture and distribution of high-performance compound and single element semiconductor substrates and sale of raw materials integral to these substrates. Our chief operating decision-maker has been identified as our Chief Executive Officer, who reviews operating results to make decisions about allocating resources and assessing our performance for the Company. We discuss revenue and capacity for both AXT and our joint ventures collectively, when determining capacity constraints and need for raw materials in our business, and consider their capacity when determining our strategic and product marketing and advertising strategies. While we consolidate our majority-owned or significantly controlled joint ventures, we do not allocate any portion of overhead, interest and other income, interest expense or taxes to them. We therefore have determined that our joint venture operations do not constitute an operating segment. Since we operate in one segment, all financial segment and product line information can be found in the consolidated financial statements.

Stock-Based Compensation

We have employee stock option plans, which are described more fully in Note 10-“Employee Benefit Plans and Stock-based Compensation”. We account for stock-based compensation in accordance with the provisions of ASC Topic 718, Compensation-Stock Compensation (“ASC 718”). We utilize the Black-Scholes option pricing model to estimate the grant date fair value of stock options, which requires the input of highly subjective assumptions, including estimating stock price volatility and expected term. Stock-based compensation cost is measured at each grant date, based on the fair value of the award, and is recognized as expense and as an increase in additional paid-in capital over the requisite service period of the award.

Research and Development

Research and development costs consist primarily of salaries, including stock-based compensation expense and related personnel costs, depreciation, materials and product testing which are expensed as incurred. Tangible assets acquired for research and development purposes are capitalized if they have alternative future use.

​

Advertising Costs

Advertising costs, included in selling, general and administrative expenses, are expensed as incurred. Advertising costs for the years ended December 31, 2023, 2022 and 2021 were insignificant.

Income Taxes

We account for income taxes in accordance with ASC Topic 740, Income Taxes (“ASC 740”), which requires that deferred tax assets and liabilities be recognized using enacted tax rates for the effect of temporary differences between the book and tax bases of recorded assets and liabilities. ASC 740 also requires that deferred tax assets be reduced by a valuation allowance if it is more likely than not that a portion of the deferred tax asset will not be realized. The impact of ASC 740 is more fully described in Note 12.

Comprehensive Income (loss)

The components of other comprehensive income (loss) include unrealized gains and losses on marketable securities and foreign currency translation adjustments. Comprehensive income (loss) is presented in the consolidated statements of comprehensive income (loss). The balance of accumulated other comprehensive income (loss) is as follows (in thousands):

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

2023

​

2022

Accumulated other comprehensive loss:

​

​

​

​

​

​

Unrealized loss on investments, net

​

$

(20)

​

$

(303)

Cumulative translation adjustment

​

 

(6,530)

​

​

(3,042)

​

​

 

(6,550)

​

​

(3,345)

Less: Cumulative translation adjustment attributable to noncontrolling interests and redeemable noncontrolling interests

​

​

(551)

​

​

(227)

Accumulated other comprehensive loss attributable to AXT, Inc.

​

$

(5,999)

​

$

(3,118)

​

Net Income (Loss) Per Share

Basic net income (loss) per share is computed using the weighted-average number of common shares outstanding during the periods less shares of common stock subject to repurchase and non-vested stock awards. Diluted net income (loss) per share is computed using the weighted-average number of common shares outstanding and potentially dilutive common shares outstanding during the periods. The dilutive effect of outstanding stock options and restricted stock awards is reflected in diluted earnings per share by application of the treasury stock method. Potentially dilutive common shares consist of common shares issuable upon the exercise of stock options and vesting of restricted stock awards. Potentially dilutive common shares are excluded from the computation of weighted-average number of common shares outstanding in net loss years, as their effect would be anti-dilutive to the computation.

Recent Accounting Pronouncements

In March 2022, the Financial Accounting Standards Board (“FASB”) pronouncement Accounting Standards Update (“ASU”) 2022-02, Financial Instruments-Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures was issued as an amendment to ASU 2016-13, Financial Instruments-Credit Losses. ASU 2022-02 aims to modify disclosure requirements for certain loan refinancings and restructurings by creditors. The amendment also require that an entity disclose current-period gross write offs by year of origination for financing receivables and net investments in leases within the scope of Subtopic 326-20, Financial Instruments—Credit Losses—Measured at Amortized Cost. The guidance is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Adoption of the new standard had an immaterial effect on our consolidated financial statements.

In September 2022, FASB issued ASU 2022-04, Liabilities—Supplier Finance Programs (Subtopic 405-50): Disclosure of Supplier Finance Program Obligations, to enhance the transparency about the use of supplier finance programs for investors. The amendments in this Update require that a buyer in a supplier finance program disclose sufficient information about the program to allow a user of financial statements to understand the program’s nature, activity during the period, changes from period to period, and potential magnitude. The guidance is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Adoption of the new standard had an immaterial effect on our consolidated financial statements.

In November 2023, FASB released ASU 2023-07— Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, aiming to enhance the transparency and relevance of segment information provided in financial statements. The amendments in this Update require that a public entity disclose significant segment expenses, profit or loss and assets, etc. for each reportable segment, on an annual and interim basis. The Update is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Adoption of the new standard will have an immaterial effect on our consolidated financial statements.

In December 2023, FASB issued ASU 2023-09— Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to help investors better understand an entity’s exposure to potential changes in jurisdictional tax legislation and the ensuing risks and opportunities. Furthermore, the Update improves to assess income tax information that affects cash flow forecasts and capital allocation decisions. The Update is effective for public business entities for annual periods beginning after December 15, 2024, on a prospective basis. Adoption of the new standard will have an immaterial effect on our consolidated financial statements.
v3.24.0.1
Cash, Cash Equivalents and Investments
 12 Months Ended
Dec. 31, 2023
Cash, Cash Equivalents and Investments  
Cash, Cash Equivalents and Investments

Note 2. Cash, Cash Equivalents and Investments

Our cash and cash equivalents consist of cash and instruments with original maturities of less than three months. Our investments consist of instruments with original maturities of more than three months. As of December 31, 2023 and 2022, our cash, cash equivalents and debt investments are classified as follows (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

December 31, 2023

​

December 31, 2022

 

​

    

​

​

    

Gross

    

Gross

    

​

​

    

​

​

    

Gross

    

Gross

    

​

​

 

​

​

Amortized

​

Unrealized

​

Unrealized

​

Fair

​

Amortized

​

Unrealized

​

Unrealized

​

Fair

 

​

    

Cost

    

Gain

    

(Loss)

    

Value

    

Cost

    

Gain

    

(Loss)

    

Value

 

Classified as:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Cash and restricted cash

​

$

50,114

​

$

—

​

$

—

​

$

50,114

​

$

41,348

​

$

—

​

$

—

​

$

41,348

​

Cash equivalents:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit 1

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

Total cash, restricted cash and cash equivalents

​

 

50,114

​

 

—

​

 

—

​

 

50,114

​

 

41,348

​

 

—

​

 

—

​

 

41,348

​

Investments (available-for-sale):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit 2

​

 

2,160

​

 

—

​

​

(20)

​

 

2,140

​

 

6,440

​

 

—

​

​

(175)

​

 

6,265

​

Corporate bonds

​

 

—

​

 

—

​

 

—

​

 

—

​

 

5,320

​

 

—

​

 

(128)

​

 

5,192

​

Total investments

​

 

2,160

​

 

—

​

 

(20)

​

 

2,140

​

 

11,760

​

 

—

​

 

(303)

​

 

11,457

​

Total cash, restricted cash, cash equivalents and investments

​

$

52,274

​

$

—

​

$

(20)

​

$

52,254

​

$

53,108

​

$

—

​

$

(303)

​

$

52,805

​

Contractual maturities on investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Due within 1 year 3

​

$

2,160

​

​

​

​

​

​

​

$

2,140

​

$

9,600

​

​

​

​

​

​

​

$

9,339

​

Due after 1 through 5 years 4

​

 

—

​

​

​

​

​

​

​

 

—

​

 

2,160

​

​

​

​

​

​

​

 

2,118

​

​

​

$

2,160

​

​

​

​

​

​

​

$

2,140

​

$

11,760

​

​

​

​

​

​

​

$

11,457

​

1.Certificate of deposit with original maturities of less than three months.
2.Certificate of deposit with original maturities of more than three months.
3.Classified as “Short-term investments” in our consolidated balance sheets.
4.Classified as “Long-term investments” in our consolidated balance sheets.

​

We manage our debt investments as a single portfolio of highly marketable securities that is intended to be available to meet our current cash requirements. Certificates of deposit and corporate bonds are typically held until maturity.

Historically, the gross unrealized losses related to our portfolio of available-for-sale debt securities were immaterial, and primarily due to normal market fluctuations and not due to increased credit risk or other valuation concerns. Gross unrealized losses on our available-for-sale debt securities as of December 31, 2023 was $20,000, and historically, such gross unrealized losses have been temporary in nature and we believe that it is probable the principal and interest will be collected in accordance with the contractual terms. We review our debt investment portfolio at least quarterly, or when there are changes in credit risks or other potential valuation concerns, to identify and evaluate whether an allowance for credit losses or impairment would be necessary. Factors considered in determining whether a loss is temporary include the magnitude of the decline in market value, the length of time the market value has been below cost (or adjusted cost), credit quality, and our ability and intent to hold the securities for a period of time sufficient to allow for any anticipated recovery in market value.

The following table summarizes the fair value and gross unrealized losses related to available-for-sale debt securities, aggregated by investment category and length of time that individual debt securities have been in a continuous unrealized loss position as of December 31, 2023 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

In Loss Position

​

In Loss Position

​

Total In

 

​

​

< 12 months

​

> 12 months

​

Loss Position

 

​

​

​

​

​

Gross

​

​

​

​

Gross

​

​

​

​

Gross

 

​

​

Fair

​

Unrealized

​

Fair

​

Unrealized

​

Fair

​

Unrealized

 

As of December 31, 2023

    

Value

    

(Losses)

    

Value

    

(Losses)

    

Value

    

(Losses)

 

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

—

​

$

—

​

$

2,140

​

$

(20)

​

$

2,140

​

$

(20)

​

Total in loss position

​

$

—

​

$

—

​

$

2,140

​

$

(20)

​

$

2,140

​

$

(20)

​

​

The following table summarizes the fair value and gross unrealized losses related to available-for-sale debt securities, aggregated by investment category and length of time that individual debt securities have been in a continuous unrealized loss position as of December 31, 2022 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

In Loss Position

​

In Loss Position

​

Total In

 

​

​

< 12 months

​

> 12 months

​

Loss Position

 

​

    

    

​

    

Gross

    

    

​

    

Gross

    

    

​

    

Gross

 

​

​

Fair

​

Unrealized

​

Fair

​

Unrealized

​

Fair

​

Unrealized

 

As of December 31, 2022

​

Value

​

(Loss)

​

Value

​

(Loss)

​

Value

​

(Loss)

 

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

2,118

​

$

(42)

​

$

4,146

​

$

(133)

​

$

6,264

​

$

(175)

​

Corporate bonds

​

 

—

​

 

—

​

 

4,842

​

 

(128)

​

 

4,842

​

​

(128)

​

Total in loss position

​

$

2,118

​

$

(42)

​

$

8,988

​

$

(261)

​

$

11,106

​

$

(303)

​

​

Investments in Privately Held Raw Material Companies

We have made strategic investments in private companies located in China in order to gain access at a competitive cost to raw materials that are critical to our substrate business (see Note 6). The investment balances for the non-consolidated companies, are accounted for under the equity method and included in “Other assets” in the consolidated balance sheets and totaled $12.5 million and $14.6 million as of December 31, 2023 and 2022, respectively. As of December 31, 2023 and 2022, there were three and six companies accounted for under the equity method, respectively.

Fair Value Measurements

We invest primarily in money market accounts, certificates of deposit, corporate bonds and notes, and government securities. ASC Topic 820, Fair Value Measurements and Disclosures (“ASC 820”), establishes three levels of inputs that may be used to measure fair value. Level 1 instrument valuations are obtained from real-time quotes for transactions in active exchange markets of the asset or identical assets. Level 2 instrument valuations are obtained from readily available, observable pricing sources for comparable instruments. Level 3 instrument valuations are obtained from unobservable inputs in which there is little or no market data, which require us to develop our own assumptions. On a recurring basis, we measure certain financial assets and liabilities at fair value, primarily consisting of our short-term and long-term debt investments.

The type of instrument valued based on quoted market prices in active markets include our money market funds, which are generally classified within Level 1 of the fair value hierarchy. We classify our available-for-sale debt securities including certificates of deposit and corporate bonds as having Level 2 inputs. The valuation techniques used to measure the fair value of these financial instruments having Level 2 inputs were derived from bank statements, quoted market prices, broker or dealer statements or quotations, or alternative pricing sources with reasonable levels of price transparency. There were no changes in valuation techniques or related inputs in the year ended December 31, 2023. There have been no transfers between fair value measurement levels during the years ended December 31, 2023 and 2022.

We place short-term foreign currency hedges that are intended to offset the potential cash exposure related to fluctuations in the exchange rate between the United States dollar and Japanese yen. We measure the fair value of these foreign currency hedges at each month end and quarter end using current exchange rates and in accordance with generally accepted accounting principles. At quarter end any foreign currency hedges not settled are netted in “Accrued liabilities” on the consolidated balance sheets and classified as Level 3 assets and liabilities. As of December 31, 2023, the net change in fair value from the placement of the hedge to settlement at each month end during the quarter had a de minimis impact to the consolidated results.

The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis in accordance with ASC 820 as of December 31, 2023 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

    

​

​

    

Quoted Prices in

    

​

​

​

Significant

 

​

​

​

​

​

Active Markets of

​

Significant Other

​

Unobservable

 

​

​

Balance as of

​

Identical Assets

​

Observable Inputs

​

Inputs

 

​

    

December 31, 2023

    

(Level 1)

    

(Level 2)

    

(Level 3)

 

Assets:

​

​

​

​

​

​

​

​

​

​

​

​

​

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

2,140

​

$

—

​

$

2,140

​

$

—

​

Corporate bonds

​

 

—

​

 

—

​

 

—

​

 

—

​

Total

​

$

2,140

​

$

—

​

$

2,140

​

$

—

​

​

The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis in accordance with ASC 820 as of December 31, 2022 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

    

​

​

    

Quoted Prices in

    

​

​

​

Significant

 

​

​

​

​

​

Active Markets of

​

Significant Other

​

Unobservable

 

​

​

Balance as of

​

Identical Assets

​

Observable Inputs

​

Inputs

 

​

    

December 31, 2022

    

(Level 1)

    

(Level 2)

    

(Level 3)

 

Assets:

​

​

​

​

​

​

​

​

​

​

​

​

​

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

6,265

​

$

—

​

$

6,265

​

$

—

​

Corporate bonds

​

 

5,192

​

 

—

​

 

5,192

​

 

—

​

Total

​

$

11,457

​

$

—

​

$

11,457

​

$

—

​

​

Items Measured at Fair Value on a Nonrecurring Basis

Certain assets that are subject to nonrecurring fair value measurements are not included in the table above. These assets include investments in privately held companies accounted for by equity and fair value method (See Note 6). For the year ended December 31, 2023, one of our PRC joint ventures assessed one of its equity investments was fully impaired. For the year ended December 31, 2023, we divested our equity investment in a PRC joint venture. The impairment and divestiture resulted in a total of $1.9 million in impairment charges in our financial results. We had no impairment charges for 2022 and 2021.

v3.24.0.1
Inventories
 12 Months Ended
Dec. 31, 2023
Inventories  
Inventories

Note 3. Inventories

The components of inventory are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

​

    

2023

    

2022

 

Inventories:

​

​

​

​

​

​

​

Raw materials

​

$

32,910

​

$

46,476

​

Work in process

​

 

50,008

​

 

39,956

​

Finished goods

​

 

3,585

​

 

3,197

​

​

​

$

86,503

​

$

89,629

​

​

As of December 31, 2023 and 2022, carrying values of inventories were net of inventory reserves of $21.9 million and $24.7 million, respectively, for excess and obsolete inventory and $78,000 and $47,000, respectively, for lower of cost or net realizable value reserves.
v3.24.0.1
Related Party Transactions
 12 Months Ended
Dec. 31, 2023
Related Party Transactions  
Related Party Transactions

Note 4. Related Party Transactions

ChaoYang Tongmei purchases raw materials from one of PRC joint ventures, Donghai County Dongfang High Purity Electronic Materials Co., Ltd. (“Dongfang”) for production in the ordinary course of business. As of December 31, 2023 and 2022, amounts payable of $0 and $103,000, respectively, were included in “Accounts payable” in our consolidated balance sheets.

In September 2021 and October 2021, our consolidated subsidiary, ChaoYang XinMei received funding from a minority investor of $0.9 million and $1.0 million, respectively. As of December 31, 2021, $1.9 million was included in short-term loan from noncontrolling interest in our consolidated balance sheets. In December 2021 and January 2022, the same subsidiary received funding from Tongmei of $1.4 million and $1.4 million, respectively. In January 2022, the China local government certified this additional funding in ChaoYang XinMei as an equity investment. As a result, noncontrolling interests increased $2.2 million and redeemable noncontrolling interests increased $0.2 million. Short-term loan from noncontrolling interest decreased to $0. In April 2022, Tongmei entered into the Capital Increase Agreement with minority investors to further invest $4.5 million in ChaoYang XinMei. In April 2022 and May 2022, ChaoYang XinMei received funding from Tongmei of $1.1 million and $0.8 million, respectively, as equity investments. In April 2022 and May 2022, the minority investors invested $0.7 million and $0.6 million, respectively. As a result, noncontrolling interests increased $1.4 million and redeemable noncontrolling interests increased $0.1 million. Tongmei’s ownership remained at 58.5% after these equity investments. In July 2022, Tongmei and the minority investors further invested $0.8 million and $0.6 million in ChaoYang XinMei, respectively. This completed the investment obligations under the Capital Increase Agreement. As a result, noncontrolling interests increased $610,000 and redeemable noncontrolling interests increased $57,000. Tongmei’s ownership remained at 58.5% after the July 2022 equity investment.

​

In September 2022, our consolidated subsidiary, ChaoYang LiMei completed the sale of land and its attached buildings to our equity investment entity, ChaoYang KaiMei, for a total consideration of $1.5 million. In January 2023, ChaoYang KaiMei paid to ChaoYang LiMei $1.5 million. As of December 31, 2023, $0 million was included in “Prepaid expenses and other current assets” in our consolidated balance sheets.

​

Our Related Party Transactions Policy seeks to prohibit all conflicts of interest in transactions between related parties and us, unless they have been approved by our Board of Directors. This policy applies to all of our employees, directors, and our consolidated subsidiaries. Our executive officers retain board seats on the Board of Directors of the companies in which we have invested in our China joint ventures. See Note 6 for further details.
v3.24.0.1
Property, Plant and Equipment, Net
 12 Months Ended
Dec. 31, 2023
Property, Plant and Equipment, Net  
Property, Plant and Equipment, Net

Note 5. Property, Plant and Equipment, Net

The components of our property, plant and equipment are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

​

​

2023

​

2022

​

Property, plant and equipment:

​

​

​

​

​

​

​

Machinery and equipment, at cost

​

$

65,918

​

$

62,797

​

Less: accumulated depreciation and amortization

​

​

(42,112)

​

​

(38,477)

​

Building, at cost

​

​

125,786

​

​

118,550

​

Less: accumulated depreciation and amortization

​

​

(23,339)

​

​

(20,403)

​

Leasehold improvements, at cost

​

 

7,596

​

 

7,430

​

Less: accumulated depreciation and amortization

​

​

(5,984)

​

​

(5,559)

​

Construction in progress

​

 

38,483

​

 

36,679

​

​

​

$

166,348

​

$

161,017

​

​

As of December 31, 2023, the balance of construction in progress was $38.5 million, of which $31.2 million was related to our buildings in our Dingxing and Kazuo locations, $3.1 million was for manufacturing equipment purchases not yet placed in service and $4.2 million was from our construction in progress for our other consolidated subsidiaries. As of December 31, 2022, the balance of construction in progress was $36.7 million, of which $27.2 million was related to our buildings in our Dingxing and Kazuo locations, $5.4 million was for manufacturing equipment purchases not yet placed in service and $4.1 million was from our construction in progress for our other consolidated subsidiaries. 

Depreciation and amortization expense was $8.7 million, $8.1 million and $7.1 million for the years ended December 31, 2023, 2022 and 2021, respectively.
v3.24.0.1
Investments in Privately-held Raw Material Companies
 12 Months Ended
Dec. 31, 2023
Investments in Privately-Held Raw Material Companies  
Investments in Privately-Held Raw Material Companies

Note 6. Investments in Privately Held Raw Material Companies

We have made strategic investments in private companies located in China in order to gain access at a competitive cost to raw materials that are critical to our substrate business. These companies form part of our overall supply chain.

The investments are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Investment Balance as of

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

Accounting

​

Ownership

*

Company

    

2023

    

2022

    

Method

    

Percentage

​

Nanjing JinMei Gallium Co., Ltd.

​

$

592

​

$

592

 

Consolidated

 

** 85.5

%

ChaoYang JinMei Gallium Co., Ltd.

​

​

1,820

​

​

1,820

​

Consolidated

​

** 85.5

%

Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd.

​

 

1,346

​

 

1,346

 

Consolidated

 

** 85.5

%

ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.

​

​

3,122

​

​

1,000

​

Consolidated

​

**** 75.0

%

ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd.

​

​

7,331

​

​

7,331

​

Consolidated

 

*** 58.5

%

​

​

$

14,211

​

$

12,089

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Beijing JiYa Semiconductor Material Co., Ltd.

​

$

3,806

​

​

6,381

​

Equity

​

39

%

Xiaoyi XingAn Gallium Co., Ltd.

​

​

5,516

​

​

5,094

​

Equity

​

** 25

%

ChaoYang KaiMei Quartz Co., Ltd.

​

​

3,154

​

​

827

​

Equity

​

***** 40

%

Emeishan Jia Mei High Purity Metals Co., Ltd.

​

 

N/A

​

 

418

 

Equity

 

****** 25

%

​

​

$

12,476

​

$

12,720

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Emeishan Jia Mei High Purity Metals Co., Ltd.

​

 

551

​

 

N/A

 

Fair value

 

****** 10

%

​

​

$

551

​

$

—

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Donghai County Dongfang High Purity Electronic Materials Co., Ltd.

​

 

—

​

 

1,887

 

N/A

 

******* 0

%

​

​

$

—

​

$

1,887

​

​

​

​

​

​

* These percentages reflect the ownership currently in effect upon the completion of the reorganization in China and the ownership in effect upon the completion of the new capital funding by private equity investors in January 2021.

​

** In preparation for Tongmei’s application for a listing of shares in an IPO on the STAR Market, in late December 2020 we reorganized our entity structures in China. JinMei and BoYu and their subsidiaries, previously organized under AXT, Inc., were assigned to Tongmei and effectively merged with Tongmei although they retained their own respective legal entity status and are wholly owned subsidiaries of Tongmei. The 33% minority interest stakeholders of BoYu converted their ownership to a 7.59% minority interest in Tongmei. The 8.5% minority interest stakeholders, employees of JinMei, converted their ownership to a 0.38% minority interest in Tongmei. Further, a number of employees, key managers and contributors, purchased a 0.4% minority interest in Tongmei. In 2020, the Investors transferred approximately $48.1 million of new capital to Tongmei. An additional investment of approximately $1.5 million of new capital was funded in early January 2021. Under China regulations these investments must be formally approved by the appropriate government agency and are not deemed to be dilutive until such approval is granted. The government approved the approximately $49 million investment in its entirety on January 25, 2021 at which time the Investors owned

a redeemable noncontrolling interest in Tongmei of 7.28%. As of December 31, 2022, Tongmei’s noncontrolling interests and redeemable noncontrolling interests totaled approximately 14.5%. AXT remains the controlling stakeholder of Tongmei and holds a majority of the Board of Director positions of Tongmei.

​

*** In February 2021, Tongmei signed a joint venture agreement with certain investors to fund ChaoYang XinMei.

​

**** In April 2022, ChaoYang JinMei signed a joint venture agreement with certain investor to fund a new company, ChaoYang ShuoMei.

​

***** In April 2022, Tongmei signed a joint venture agreement with certain investors to fund a new company, ChaoYang KaiMei.

​

****** In May 2023, we sold 15% of our equity investments in Jia Mei to a third party. We now own 10% of the equity ownership of Jia Mei and account for it under the fair value method.

​

******* In November 2023, we completed the sale of our entire 46% equity ownership interests in Dongfang to a third party.

In May 2023, we reduced our ownership in Jia Mei from 25% to 10% by selling a portion of our Jia Mei shares to an unrelated third party for approximately $827,000. Considering our decreased ownership and that we no longer have significant influence over its operations and financial policies, we adopted the fair value method of accounting to report on the investment in Jia Mei. As Jia Mei's equity interest is without a readily determinable fair value, we elected to use the measurement alternative to measure at cost, less any impairment, plus or minus fair value changes resulting from observable price changes in orderly transactions for identical or similar investments of the same issuer. As a result of the share sale, we recognized a gain of $575,000. Additionally, in accordance with ASC 321-10-35-2, we adjusted the investment in Jia Mei to its fair value at the time of the sale. The gain resulting from the sale and the subsequent remeasurement was incorporated as a component of “Equity in income of unconsolidated joint ventures” in the consolidated statements of operations for the twelve months ended December 31, 2023. The gain from the sale and the subsequent remeasurement includes the following:

​

​

​

​

​

​

​

Amount

​

    

(in thousands)

Fair value of the consideration received

​

$

779

Foreign income tax withholding

​

​

48

Carrying value of 15% of Emeishan Jia Mei High Purity Metals Co., Ltd.

​

​

(252)

Gain recognized on sale of 15% of Emeishan Jia Mei High Purity Metals Co., Ltd.

​

$

575

​

​

​

​

​

​

​

​

​

​

Amount

​

​

(in thousands)

Fair value of the retained investment in Emeishan Jia Mei High Purity Metals Co., Ltd.

​

$

551

Carrying value of retained noncontrolling investment (10%)

​

​

(168)

Gain on retained noncontrolling investment due to remeasurement (10%)

​

$

383

​

​

The Jia Mei investment is reviewed for other-than-temporary declines in value on a quarterly basis. We did not record any other-than-temporary impairment charges for Jia Mei investment during the twelve months ended December 31, 2023.

​

In November 2023, our 46% equity ownership interest in Dongfang was sold to a third party for consideration valued at approximately $0.6 million, including raw materials, equipment, and vehicle. As a result, our equity ownership interest of Dongfang decreased from 46% to 0%. The loss resulting from the sale was incorporated as a component of “Equity in income of unconsolidated joint ventures” in the consolidated statements of operations for the twelve months ended December 31, 2023. The loss from the sale includes the following:

​

​

​

​

​

​

​

Amount

​

    

(in thousands)

Fair value of the consideration received

​

$

585

Carrying value of 46% of Donghai County Dongfang High Purity Electronic Materials Co., Ltd.

​

​

(1,710)

Loss recognized on sale of 46% of Donghai County Dongfang High Purity Electronic Materials Co., Ltd.

​

$

(1,125)

​

Although we have representation on the board of directors of each of the privately held raw material companies, the daily operations of each of these companies are managed by local management and not by us. Decisions concerning their respective short-term strategy and operations, ordinary course of business capital expenditures and sales of finished product, are made by local management with regular guidance and input from us.

For AXT’s minority investment entities that are not consolidated, the investment balances are included in “Other assets” in our consolidated balance sheets and totaled $12.5 million and $14.6 million as of December 31, 2023 and 2022, respectively. Our respective ownership interests in ChaoYang KaiMei, JiYa, Xiaoyi XingAn and Jia Mei was 40%, 39%, 25%, and 10%, respectively. These minority investment entities are not considered variable interest entities because:

●all minority investment entities have sustainable businesses of their own;
●our voting power is proportionate to our ownership interests;
●we only recognize our respective share of the losses and/or residual returns generated by the companies if they occur; and
●we do not have controlling financial interest in, do not maintain operational or management control of, do not control the board of directors of, and are not required to provide additional investment or financial support to any of these companies.

Occasionally, one of our PRC subsidiaries or PRC raw material joint ventures declares and pays a dividend. These dividends generally occur when the PRC joint venture declares a dividend for all of its shareholders. Dividends paid to the Company are subject to a 10% PRC withholding tax. The Company is required to obtain approval from the State Administration of Foreign Exchange (“SAFE”) to transfer funds in or out of the PRC. SAFE requires a valid agreement to approve the transfers, which are processed through a bank. Other than PRC foreign exchange restrictions, the Company is not subject to any PRC restrictions and limitations on its ability to distribute earnings from its businesses, including its PRC subsidiaries and PRC joint ventures, to the Company and its investors as well as the ability to settle amounts owed by the Company to its PRC subsidiaries and PRC joint ventures. If SAFE approval is denied the dividend payable to the Company would be owed but would not be paid.

For the years ended December 31, 2023, 2022 and 2021, the aggregate dividends paid to us, directly or to an intermediate entity within our corporate structure, by our PRC subsidiaries and PRC raw material joint ventures were approximately $4.3 million, $2.9 million and $774,000, respectively. In June 2021, we received a dividend of $774,000 from Xiaoyi XingAn. In June 2022, July 2022 and August 2022, we received a dividend of $1.3 million from BoYu, $1.5 million from Xiaoyi XingAn and $0.1 million from JiYa, respectively. In April 2023, Xiaoyi XingAn distributed a dividend of $1.8 million to us. Additionally, in both April 2023 and November 2023, JiYa distributed dividends to us, totaling $2.0 million and $0.5 million, respectively. For the years ended December 31, 2023 and 2022, there were no dividends paid to minority shareholders by our PRC subsidiaries or PRC raw material joint ventures.

AXT’s minority investment entities are not consolidated and are accounted for under the equity method. The equity entities had the following summarized income information (in thousands) for the years ended December 31, 2023, 2022 and 2021, respectively: (The 2023 income information includes results of Jia Mei for Q1 and Q2.)

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Our share for the

 

​

​

​

Year Ended

​

Year Ended

 

​

​

​

December 31, 

​

December 31, 

 

​

    

2023

    

2022

​

2021

    

2023

    

2022

    

2021

 

Net revenue

​

$

32,544

​

$

48,139

​

$

35,939

​

$

10,033

​

$

15,031

​

$

11,424

​

Gross profit

​

 

11,698

​

 

27,000

​

 

17,465

​

 

3,365

​

 

8,229

​

 

5,482

​

Operating income

​

 

10,115

​

 

24,987

​

 

14,293

​

 

2,724

​

 

7,532

​

 

4,495

​

Net income

​

​

8,681

​

​

19,104

​

​

12,560

​

​

1,884

​

​

5,957

​

​

4,409

​

​

These minority investment entities that are not consolidated, but rather are accounted for under the equity method, had the following summarized balance sheet information (in thousands) as of December 31, 2023 and 2022, respectively: (The 2023 balance sheet information excludes Jia Mei.)

​

​

​

​

​

​

​

​

​

​

As of December 31, 

 

​

    

2023

​

2022

 

Current assets

​

$

31,636

    

$

43,091

​

Noncurrent assets

​

 

19,751

​

 

12,520

​

Current liabilities

​

 

7,367

​

 

10,552

​

Noncurrent liabilities

​

 

—

​

 

—

​

​

Our portion of the income and losses, including impairment charges, from these minority investment entities that are not consolidated and are accounted for under the equity method was an income of $1.9 million, $6.0 million and $4.4 million for the years ended December 31, 2023, 2022 and 2021, respectively. Undistributed retained earnings relating to our investments in these minority investment entities amounted to $8.1 million and $9.2 million as of December 31, 2023 and 2022, respectively.

v3.24.0.1
Balance Sheets Details
 12 Months Ended
Dec. 31, 2023
Balance Sheets Details  
Balance Sheets Details

Note 7. Balance Sheets Details

Other Assets

The components of other assets are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

 

2023

    

2022

​

Equity method investments

​

​

$

12,476

​

$

14,607

​

Value added tax receivable, long term

​

​

​

1,291

​

​

1,632

​

Other intangible assets

​

​

​

1,821

​

​

1,926

​

Deferred tax assets

​

​

​

1,683

​

​

2,236

​

Other assets

​

​

​

1,627

​

​

1,230

​

​

​

​

$

18,898

​

$

21,631

​

​

Accrued Liabilities

The components of accrued liabilities are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

​

 

2023

    

2022

 

Payable in connection with construction in progress

​

$

7,249

​

$

4,135

​

Accrued compensation and related charges

​

​

3,707

​

​

4,774

​

Preferred stock dividends payable

​

​

2,901

​

​

2,901

​

Accrued professional services

​

​

868

​

​

930

​

Accrued product warranty

​

​

703

​

​

669

​

Other tax payable

​

​

493

​

​

867

​

Current portion of operating lease liabilities

​

​

458

​

​

485

​

Advances from customers

​

​

305

​

​

338

​

Other personnel-related costs

​

​

286

​

​

291

​

Accrual for sales returns

​

​

39

​

​

112

​

Accrued income taxes

​

​

—

​

​

729

​

Other accrued liabilities

​

​

2,010

​

​

1,933

​

​

​

$

19,019

​

$

18,164

​

​

​

​

​

​

​

​

​

​
v3.24.0.1
Bank Loans and Line of Credit
 12 Months Ended
Dec. 31, 2023
Bank Loans and Line of Credit  
Bank Loans and Line of Credit

Note 8. Bank Loans and Line of Credit

Our bank loans and credit facilities typically have a term of 12 months or less and are included in “Bank loan” in our consolidated balance sheets. The following table represents bank loans as of December 31, 2023 and 2022 (in thousands, except interest rate data):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Loan

Interest

​

​

​

​

​

December 31, 

​

December 31, 

Subsidiary

Bank

​

Detail

Rate

​

Start Date

​

Due Date

​

2022

​

2023

Tongmei

Bank of China (1)

$

2,108

2.7

%  

September-22

​

March-23

$

2,175

$

-

​

​

​

3,935

4.6

%  

January-22

​

January-23

​

4,059

​

-

​

​

​

1,405

4.2

%  

April-22

​

April-23

​

1,450

​

-

​

Bank of China (5)

​

1,848

3.5

%  

January-23

​

January-24

​

-

​

1,795

​

​

​

2,184

2.8

%  

March-23

​

March-24

​

-

​

2,118

​

​

​

376

2.7

%  

September-23

​

September-24

​

-

​

386

​

​

​

876

3.5

%  

November-23

​

November-24

​

-

​

876

​

​

​

1,003

3.5

%  

November-23

​

November-24

​

-

​

1,003

​

Bank of China (3)

​

2,911

3.5

%  

January-23

​

January-24

​

-

​

2,825

​

Bank of Communications (2)

​

1,405

3.3

%  

January-22

​

January-23

​

1,450

​

-

​

​

​

1,405

3.3

%  

January-22

​

January-23

​

1,450

​

-

​

Bank of Communications (5)

​

1,450

3.3

%  

December-22

​

December-23

​

1,450

​

-

​

​

​

1,455

3.3

%  

January-23

​

January-24

​

-

​

1,414

​

​

​

1,380

3.8

%  

May-23

​

May-24

​

-

​

1,414

​

​

​

1,373

3.8

%  

July-23

​

May-24

​

-

​

1,414

​

China Merchants Bank (5)

​

4,367

3.7

%  

January-23

​

January-24

​

-

​

4,235

​

Bank of Beijing (4)

​

3,192

4.2

%  

May-22

​

May-23

​

3,292

​

-

​

​

​

2,290

4.2

%  

January-23

​

January-24

​

-

​

2,220

​

​

​

3,541

3.2

%  

June-23

​

May-24

​

-

​

3,626

​

​

​

1,380

3.2

%  

June-23

​

February-24

​

-

​

1,414

​

​

​

1,414

3.0

%  

December-23

​

December-24

​

-

​

1,414

​

Industrial Bank (5)

​

5,621

4.4

%  

June-22

​

June-23

​

5,798

​

-

​

​

​

2,811

4.4

%  

September-22

​

September-23

​

2,900

​

-

​

​

​

2,757

4.3

%  

June-23

​

June-24

​

-

​

2,825

​

​

​

2,744

4.3

%  

July-23

​

July-24

​

-

​

2,825

​

​

​

2,744

4.3

%  

September-23

​

September-24

​

-

​

2,825

​

NingBo Bank (5)

​

1,405

4.8

%  

June-22

​

June-23

​

1,450

​

-

​

​

​

1,405

4.8

%  

August-22

​

August-23

​

1,450

​

-

​

​

​

1,405

4.8

%  

September-22

​

September-23

​

1,450

​

-

​

​

​

1,406

4.5

%  

November-22

​

November-23

​

1,450

​

-

​

​

​

2,900

4.5

%  

December-22

​

December-23

​

2,900

​

-

​

​

​

2,744

4.2

%  

August-23

​

September-24

​

-

​

2,820

​

​

​

1,271

4.3

%  

November-23

​

November-24

​

-

​

1,271

​

​

​

2,825

4.3

%  

December-23

​

December-24

​

-

​

2,825

​

Industrial and Commercial Bank of China (5)

​

5,621

3.2

%  

September-22

​

July-23

​

5,800

​

-

​

​

​

2,744

3.3

%  

September-23

​

September-24

​

-

​

2,825

​

NanJing Bank (5)

​

2,811

4.3

%  

September-22

​

September-23

​

2,899

​

-

​

​

​

1,265

4.3

%  

November-22

​

November-23

​

1,305

​

-

​

​

​

2,752

3.8

%  

October-23

​

October-24

​

-

​

2,752

BoYu

Industrial and Commercial Bank of China (6)

​

1,450

2.8

%  

December-22

​

December-23

​

1,450

​

-

​

​

​

1,414

2.7

%  

December-23

​

December-24

​

-

​

1,414

​

Bank of China (5)

​

1,204

2.4

%  

January-23

​

January-24

​

-

​

849

​

NingBo Bank (5)

​

703

4.8

%  

September-22

​

March-23

​

725

​

-

​

​

​

1,406

3.6

%  

November-22

​

May-23

​

1,450

​

-

​

​

​

725

4.8

%  

December-22

​

June-23

​

725

​

-

​

​

​

1,414

3.3

%  

November-23

​

May-24

​

-

​

1,414

​

Industrial Bank (5)

​

688

3.6

%  

September-23

​

September-24

​

-

​

708

​

Bank of Communications (5)

​

1,414

3.0

%  

November-23

​

May-24

​

-

​

1,414

​

Loan Balance

​

​

​

​

​

​

​

$

47,078

$

52,921

Collateral for the above bank loans and line of credit

(1)Baoding Tongmei’s land use rights and all of its buildings located at its facility in Dingxing, China.
(2)ChaoYang Tongmei’s land use rights and all of its buildings located at its facility in Kazuo, China.
(3)ChaoYang LiMei time deposit.
(4)AXT time deposit.
(5)Not collateralized.
(6)BoYu’s land use rights and its building located at its facility in Tianjin, China. In addition, the December 2023 loan attracts a guarantee fee amounting to 0.7% of the loan amount.
v3.24.0.1
Stockholders' Equity and Stock Repurchase Program
 12 Months Ended
Dec. 31, 2023
Stockholders' Equity and Stock Repurchase Program  
Stockholders' Equity and Stock Repurchase Program

Note 9. Stockholders’ Equity and Stock Repurchase Program

Stockholders’ Equity

The 883,000 shares of $0.001 par value Series A preferred stock issued and outstanding as of December 31, 2023 and 2022, valued at $3,532,000 are non-voting and non-convertible preferred stock with a 5.0% cumulative annual dividend rate payable when declared by the Board of Directors and $4 per share liquidation preference over common stock, and must be paid before any distribution is made to common stockholders. These preferred shares were issued to Lyte Optronics, Inc. stockholders in connection with the completion of our acquisition of Lyte Optronics, Inc. on May 28, 1999.

Changes in AXT, Inc.’s ownership interests in consolidated subsidiaries

The effects of changes in the Company’s ownership interests in its less than 100% owned subsidiaries on the Company’s equity are as follows:

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

2023

​

2022

Net income (loss) attributable to AXT, Inc.

​

$

(17,881)

    

$

15,811

Decrease in additional paid-in capital for:

​

 

​

​

 

​

Investment in subsidiary with noncontrolling interest

​

 

(308)

​

 

(937)

Change from net income (loss) attributable to AXT, Inc., net of transfers to noncontrolling interests

​

$

(18,189)

​

$

14,874

​

Stock Repurchase Program

On October 27, 2014, our Board of Directors approved a stock repurchase program pursuant to which we may repurchase up to $5.0 million of our outstanding common stock. These repurchases can be made from time to time in the open market and are funded from our existing cash balances and cash generated from operations. During 2015, we repurchased approximately 908,000 shares at an average price of $2.52 per share for a total purchase price of approximately $2.3 million under the stock repurchase program. No shares were repurchased during 2023, 2022 and 2021 under this program. As of December 31, 2023, approximately $2.7 million remained available for future repurchases under this program. 

By the terms of the Series A preferred stock, so long as any shares of Series A preferred stock are outstanding, neither the Company nor any subsidiary of the Company shall redeem, repurchase or otherwise acquire any shares of common stock, unless all accrued dividends on the Series A preferred stock have been paid. During 2013 and 2015, we repurchased shares of our outstanding common stock. As of December 31, 2015, the Series A preferred stock had cumulative dividends of $2.9 million and we included this amount in “Accrued liabilities” in our consolidated balance sheets. In 2023, 2022 and 2021, we did not repurchase any of our outstanding common stock. If we are required to pay the cumulative dividends on the Series A preferred stock, our cash and cash equivalents would be reduced. We account for the cumulative year to date dividends on the Series A preferred stock when calculating our earnings per share.
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation
 12 Months Ended
Dec. 31, 2023
Employee Benefit Plans and Stock-based Compensation  
Stock-Based Compensation

Note 10. Employee Benefit Plans and Stock-based Compensation

Stock Option Plans and Equity Incentive Plans

In May 2007, our stockholders approved our 2007 Equity Incentive Plan (the “2007 Plan”), which provides for the grant of incentive and non-qualified stock options to our employees, consultants and directors. The 2007 Plan is a restatement of the 1997 Stock Option Plan which expired in 2007. The 1,928,994 share reserve of the 1997 Stock Option Plan became the reserve of the 2007 Plan, together with 1,300,000 additional shares approved for issuance under the 2007 Plan. In May 2013, the stockholders approved an additional 2,000,000 shares to be issued under the 2007 plan. Awards may be made under the 2007 Plan are stock options, stock appreciation rights, restricted stock, restricted stock

units, performance shares, performance units, deferred compensation awards and other stock-based awards. Stock options and stock appreciation rights awarded under the 2007 Plan may not be repriced without stockholder approval. Stock options and stock appreciation rights may not be granted below fair market value. Stock options or stock appreciation rights generally shall not be fully vested over a period of less than three years from the date of grant and cannot be exercised more than 10 years from the date of grant. Restricted stock, restricted stock units, and performance awards generally shall not vest faster than over a three-year period (or a twelve-month period if vesting is based on a performance measure). In December 2008, the 2007 Plan was amended to comply with the applicable requirements under Section 409A of the Internal Revenue Code.

In May 2015, our stockholders approved our 2015 Equity Incentive Plan (the “2015 Plan”). The 2015 Plan is a replacement of the 2007 Plan. The 399,562 share reserve of the 2007 Plan became the reserve of the 2015 Plan, together with 3,000,000 additional shares approved for issuance under the 2015 Plan. In May 2019, our stockholders approved 1,600,000 of additional shares for issuance under the 2015 Plan. In May 2021, our stockholders approved 3,600,000 of additional shares for issuance under the 2015 Plan. Awards that may be made under the 2015 Plan are stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares, performance units, deferred compensation awards and other stock-based awards. Stock options and stock appreciation rights awarded under the 2015 Plan may not be repriced without stockholder approval. Stock options and stock appreciation rights may not be granted below fair market value. Stock options or stock appreciation rights generally shall not be fully vested over a period of less than four years from the date of grant and cannot be exercised more than 10 years from the date of grant. Restricted stock, restricted stock units, and performance awards generally shall not vest faster than over a three-year period (or a twelve-month period if vesting is based on a performance measure). However, options granted to consultants and restricted stock awards granted to independent board members typically vest in one year and the 2015 Plan does allow for similar vesting to employees. As of December 31, 2023, approximately 1.7 million shares were available for grant under the 2015 Plan.

Stock Options

The following table summarizes the stock option transactions for each of the years ended December 31, 2021, 2022 and 2023 (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Weighted-

​

​

​

​

​

    

​

    

​

​

    

average

    

​

​

 

​

​

​

​

Weighted-

​

Remaining

​

​

​

 

​

​

Number of

​

average

​

Contractual

​

Aggregate

 

​

​

Options

​

Exercise

​

Life

​

Intrinsic

 

Stock Options

    

Outstanding

    

Price

    

(in years)

    

Value

 

Balance as of January 1, 2021

 

1,885

​

$

4.42

 

6.17

​

$

9,713

​

Granted

 

—

​

 

—

​

​

​

​

​

​

Exercised

 

(507)

​

 

3.30

​

​

​

​

​

​

Canceled and expired

 

—

​

 

—

​

​

​

​

​

​

Balance as of December 31, 2021

 

1,378

​

$

4.83

 

5.60

​

$

5,573

​

Granted

 

—

​

 

—

​

​

​

​

​

​

Exercised

 

(172)

​

 

3.02

​

​

​

​

​

​

Canceled and expired

 

—

​

 

—

​

​

​

​

​

​

Balance as of December 31, 2022

​

1,206

​

$

5.09

 

5.08

​

$

630

​

Granted

 

—

​

 

—

​

​

​

​

​

​

Exercised

 

(4)

​

​

2.30

​

​

​

​

​

​

Canceled and expired

 

(4)

​

​

4.12

​

​

​

​

​

​

Balance as of December 31, 2023

 

1,198

​

$

5.10

 

4.09

​

$

14

​

Options vested as of December 31, 2023 and unvested options expected to vest, net of forfeitures

 

1,198

​

$

5.10

 

4.09

​

$

14

​

Options exercisable as of December 31, 2023

 

1,198

​

$

5.10

 

4.09

​

$

14

​

​

The options outstanding and exercisable as of December 31, 2023 were in the following exercise price ranges (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Options Vested and

 

​

​

​

​

​

​

Options Outstanding as of

​

Exercisable as of

 

​

​

​

​

​

​

December 31, 2023

​

December 31, 2023

 

​

​

​

​

​

​

​

    

​

​

    

Weighted‑average

    

​

    

​

​

 

Range of

​

​

​

Weighted‑average

    

Remaining

​

​

​

Weighted‑Average

 

Exercise Price

​

Shares

​

Exercise Price

    

Contractual Life

​

Shares

​

Exercise Price

 

$

2.14

-

$

2.14

​

8

​

$

2.14

 

0.33

 

8

​

$

2.14

​

$

2.18

-

$

2.18

​

54

​

$

2.18

 

1.84

 

54

​

$

2.18

​

$

2.47

-

$

2.47

​

15

​

$

2.47

 

0.84

 

15

​

$

2.47

​

$

2.56

-

$

2.56

​

10

​

$

2.56

 

2.01

 

10

​

$

2.56

​

$

3.06

-

$

3.06

​

330

​

$

3.06

 

5.85

 

330

​

$

3.06

​

$

5.21

-

$

5.21

​

352

​

$

5.21

 

2.82

 

352

​

$

5.21

​

$

5.77

-

$

5.77

​

245

​

$

5.77

 

4.85

 

245

​

$

5.77

​

$

7.95

-

$

7.95

​

60

​

$

7.95

 

3.08

 

60

​

$

7.95

​

$

9.50

-

$

9.50

​

124

​

$

9.50

 

3.82

 

124

​

$

9.50

​

​

​

​

​

​

​

1,198

​

$

5.10

 

4.09

 

1,198

​

$

5.10

​

​

There were 4,000, 172,000 and 507,000 options exercised in the years ended December 31, 2023, 2022 and 2021, respectively. The total intrinsic value of options exercised for the years ended December 31, 2023, 2022 and 2021, was $7,000, $0.8 million and $3.7 million, respectively.

As of December 31, 2023, the unamortized compensation costs related to unvested stock options granted to employees under our 2015 plan was $0. We did not capitalize any stock-based compensation to inventory as of December 31, 2023 and 2022, as the amount was insignificant.

Restricted Stock Awards

A summary of activity related to restricted stock awards for the years ended December 31, 2021, 2022 and 2023 is presented below (in thousands, except per share data):

​

​

​

​

​

​

​

​

    

​

    

Weighted-Average

 

​

​

​

​

Grant Date

 

Stock Awards

    

Shares

    

Share Value

 

Non-vested as of January 1, 2021

 

1,022

​

$

5.27

​

Granted

 

274

​

$

9.07

​

Vested

 

(407)

​

$

5.70

​

Forfeited

 

(14)

​

$

5.38

​

Non-vested as of December 31, 2021

 

875

​

$

6.26

​

Granted

 

513

​

$

4.67

​

Vested

 

(387)

​

$

6.01

​

Forfeited

 

(17)

​

$

5.34

​

Non-vested as of December 31, 2022

​

984

​

$

5.55

​

Granted

 

692

​

$

2.20

​

Vested

 

(446)

​

$

5.25

​

Forfeited

​

(10)

​

$

6.37

​

Non-vested as of December 31, 2023

 

1,220

​

$

3.75

​

​

Total fair value of stock awards vested during the years ended December 31, 2023, 2022 and 2021 was $2.3 million, $2.3 million and $3.8 million, respectively. As of December 31, 2023, we had $4.1 million of unrecognized compensation expense related to restricted stock awards, which will be recognized over the weighted average period of 1.5 years.

At-Risk, Performance Shares

​

In February 2021 and 2022 and March 2023, the Company issued at-risk, performance shares classified as equity awards. Expense is recognized quarterly on a straight-line method over the requisite service period, based on the probability of achieving the specified financial performance metric, with changes in expectations recognized as an adjustment to earnings in the period of change. Compensation cost is not recognized for at-risk, performance shares that do not vest because service or performance conditions are not satisfied and any previously recognized compensation cost is reversed. At-risk, performance shares are eligible to receive dividend equivalents under the Company's 2015 Equity Incentive Plan (the “Plan”), as determined by the Board of Directors. The Company will recognize forfeitures as they occur.

​

The Company's at-risk, performance shares are classified as equity and contain performance and service conditions that must be satisfied for an employee to receive the shares. The financial performance metric for the at-risk, performance shares issued in February 2021 is based upon year-end 2020 actual results as compared to the Company’s year-end actual results in 2021. The financial performance metric for the at-risk, performance shares issued in February 2022 is based upon year-end 2021 actual results as compared to the Company’s year-end actual results in 2022. The financial performance metrics for the at-risk, performance shares issued in March 2023 are based upon the Company’s year-end actual results in 2023. The financial performance metric for the at-risk, performance shares issued in February 2024 is based upon the Company’s year-end actual results in 2024. All performance shares, if earned, are still subject to annual vesting over a four-year period, except that no shares are vested on the first anniversary because the performance measurement is based on year-end results for the year 2021, 2022 and 2023, respectively.

​

The fair value of the at-risk, performance shares is determined based on the closing price of the Company’s common stock on the first day after the public issuance of the Company’s earnings release for the most recent fiscal quarter, following the Compensation Committee and Board of Directors approval, which is considered the grant date. The fair value per share of the at-risk, performance shares classified as equity awards granted in February 2021 and 2022 and March 2023 was $15.37, $7.83 and $3.71, respectively.

​

On February 17, 2021, the Compensation Committee recommended, and the Board approved, the grant to Dr. Morris Young, our Chief Executive Officer, of 113,130 at-risk, performance shares under the Plan. On February 17, 2021, the Compensation Committee approved the grant to Gary Fischer, our Chief Financial Officer and Corporate Secretary, of 38,475 at-risk, performance shares under the Plan. On March 14, 2022, the Compensation Committee met and certified that the year-over-year annual revenue growth rate achieved for fiscal year 2021, expressed as a percentage, was 44%. Therefore, all of the at-risk performance shares became eligible to vest.

​

On February 15, 2022, the Compensation Committee recommended, and the Board approved, the grant to Dr. Morris Young of 114,320 at-risk, performance shares under the Plan. On February 15, 2022, the Compensation Committee approved the grant to Gary Fischer of 32,100 at-risk, performance shares under the Plan. If the performance financial metric is less than 50% achieved these shares are forfeited. If the performance financial metric is between 50% and 200% achieved, then a corresponding pro rata portion of the 114,320 shares issued to Dr. Young would be eligible to vest and a corresponding pro rata portion of the 32,100 shares issued to Mr. Fischer would be eligible to vest. Any shares that are not eligible to vest are forfeited. If the target financial metric exceeds 200%, then the maximum number of at-risk performance shares that would be eligible to vest is 114,320 for Dr. Young and 32,100 for Mr. Fischer. On February 14, 2023, the Compensation Committee met and certified the year-over-year annual revenue growth rate achieved for fiscal year 2022, expressed as a percentage, was 2.7%. Therefore, none of the at-risk performance shares became eligible to vest.

​

On March 15, 2023, the Compensation Committee recommended, and the Board approved, the grant to Dr. Morris Young of 223,590 at-risk, performance shares under the Plan. On March 15, 2023, the Compensation Committee approved the grant to Gary Fischer of 77,600 at-risk, performance shares under the Plan. If the minimum financial metric for fiscal year 2023 is achieved, then based upon a performance formula, a corresponding portion of the 223,590 shares issued to Dr. Young would be eligible to vest and a corresponding portion of the 77,600 shares issued to Mr. Fischer would be eligible to vest. If the target financial metric is exceeded and an additional financial metric for fiscal year 2023 is achieved, then additional shares above the target number of shares are earned based on such performance formula and the maximum number of additional shares earned is capped at 100% of the target. If the minimum financial metric for fiscal year 2023

is not achieved, then these awards are forfeited. On February 20, 2024, the Compensation Committee met and certified that the minimum revenue metric for fiscal year 2023 was not achieved. Therefore, none of the at-risk performance shares became eligible to vest.

​

On February 20, 2024, the Compensation Committee recommended, and the Board approved, the grant to Dr. Morris Young of 223,590 at-risk, performance shares under the Plan. On February 20, 2024, the Compensation Committee approved the grant to Gary Fischer of 77,600 at-risk, performance shares under the Plan. If the minimum financial metric for fiscal year 2024 is achieved, then based upon a performance formula, a corresponding portion of the 223,590 shares issued to Dr. Young would be eligible to vest and a corresponding portion of the 77,600 shares issued to Mr. Fischer would be eligible to vest. If the target financial metric is exceeded, then additional shares above the target number of shares are earned based on such performance formula and the maximum number of additional shares earned is capped at 100% of the target. If the minimum financial metric for fiscal year 2024 is not achieved, then these awards are forfeited.

​

A summary of the status of our unvested at-risk, performance shares as of December 31, 2023 is presented below (in thousands, except per share data):

​

​

​

​

​

​

​

    

​

    

Weighted-Average

​

​

​

​

Grant Date

Stock Awards

    

Shares

    

Share Value

Non-vested as of January 1, 2022

 

152

*

$

15.37

Granted

 

74

​

$

7.83

Vested

 

(76)

​

$

15.37

Forfeited

 

(74)

​

$

7.83

Non-vested as of December 31, 2022

​

76

​

$

15.37

Granted

 

13

​

$

3.71

Vested

 

(38)

​

$

15.37

Forfeited

​

(13)

​

$

3.71

Non-vested as of December 31, 2023

 

38

​

$

15.37

*The number of share presented is based on achieving 150% of the targeted financial performance metric as defined in the at-risk, performance shares agreement.

​

As of December 31, 2023, there was $0.1 million of unrecognized compensation expense related to unvested at-risk, performance shares that is expected to be recognized over a weighted-average period of 0.85 years.

Common Stock

The following number of shares of common stock were reserved and available for future issuance as of December 31, 2023 (in thousands, except per share data):

​

​

​

​

Options outstanding

    

1,198

​

Restricted stock awards outstanding

 

1,257

​

Stock available for future grant: 2015 Equity Incentive Plan

 

1,743

​

Total

 

4,198

​

​

Stock-based Compensation

We recorded $3.5 million, $4.0 million and $4.5 million of stock-based compensation in our consolidated statements of operations for the years ended December 31, 2023, 2022 and 2021, respectively. The following table summarizes compensation costs related to our stock-based compensation awards (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

​

December 31, 

​

​

 

2023

    

2022

​

2021

 

Cost of revenue

​

$

414

​

$

379

​

$

368

​

Selling, general and administrative

​

 

2,502

​

 

2,947

​

 

3,514

​

Research and development

​

 

624

​

 

680

​

 

637

​

Net effect on net income (loss)

​

$

3,540

​

$

4,006

​

$

4,519

​

Shares used in computing basic net income (loss) per share

​

 

42,643

​

 

42,104

​

 

41,367

​

Shares used in computing diluted net income (loss) per share

​

 

42,643

​

 

42,715

​

 

42,720

​

Effect on basic net income (loss) per share

​

$

0.08

​

$

0.10

​

$

0.11

​

Effect on diluted net income (loss) per share

​

$

0.08

​

$

0.09

​

$

0.11

​

​

We estimate the fair value of stock options using a Black-Scholes option pricing model. There were no stock options granted during 2023, 2022 and 2021.

The expected term for stock options is based on the observed historical option exercise behavior and post-vesting forfeitures of options by our employees, and the contractual term, the vesting period and the expected term of the outstanding options. Expected volatility is based on the historical volatility of our common stock. The dividend yield of zero is based on the fact that we have never paid cash dividends and have no present intention to pay cash dividends. The risk-free interest rates are taken from the Daily Federal Yield Curve Rates as of the grant dates as published by the Federal Reserve and represent the yields on actively traded Treasury securities for terms equal to the expected term of the options.

Retirement Savings Plan

We have a 401(k) Savings Plan (“Savings Plan”) which qualifies as a thrift plan under Section 401(k) of the Internal Revenue Code. All full-time U.S. employees are eligible to participate in the Savings Plan after 90 days from the date of hire. Employees may elect to reduce their current compensation by up to the statutory prescribed annual limit and have the amount of such reduction contributed to the 401(k) Plan. We provide matching to employee contributions up to 4% of the employees’ base pay if employees contribute at least 6% of their base pay. If the contribution rate is less than 6% of the base pay, the matching percentage is prorated. Our contributions to the Savings Plan were $186,000, $191,000 and $208,000 for the years ended December 31, 2023, 2022 and 2021, respectively.
v3.24.0.1
Guarantees
 12 Months Ended
Dec. 31, 2023
Guarantees  
Guarantees

Note 11. Guarantees

Indemnification Agreements

We have entered into indemnification agreements with our directors and officers that require us to indemnify our directors and officers against liabilities that may arise by reason of their status or service as directors or officers, other than liabilities arising from willful misconduct of a culpable nature; to advance their expenses incurred as a result of any proceeding against them as to which they could be indemnified; and to obtain directors’ and officers’ insurance if available on reasonable terms, which we currently have in place.

Product Warranty

We provide warranties for our products for a specific period of time, generally twelve months, against material defects. We provide for the estimated future costs of warranty obligations in cost of sales when the related revenue is recognized. The accrued warranty costs represent the best estimate at the time of sale of the total costs that we expect to

incur to repair or replace product parts that fail while still under warranty. The amount of accrued estimated warranty costs are primarily based on historical experience as to product failures as well as current information on repair costs. On a quarterly basis, we review the accrued balances and update the historical warranty cost trends. The following table reflects the change in our warranty accrual which is included in “Accrued liabilities” on the consolidated balance sheets, during 2023 and 2022 (in thousands):

​

​

​

​

​

​

​

​

​

​

Year Ended

 

​

​

December 31, 

 

​

    

2023

    

2022

 

Beginning accrued product warranty

​

$

669

​

$

743

​

Accruals for warranties issued

​

 

794

​

 

1,024

​

Adjustments related to pre-existing warranties including expirations and changes in estimates

​

 

(159)

​

 

(286)

​

Cost of warranty repair

​

 

(601)

​

 

(812)

​

Ending accrued product warranty

​

$

703

​

$

669

​

​
v3.24.0.1
Income Taxes
 12 Months Ended
Dec. 31, 2023
Income Taxes  
Income Taxes

Note 12. Income Taxes

Consolidated income before provision for income taxes was a loss of $19.0 million for the year ended December 31, 2023 and income of $20.9 million and $17.6 million for the years ended December 31, 2022 and 2021, respectively. We recorded a current tax provision of $0.2 million, $2.2 million and $1.1 million for the years ended December 31, 2023, 2022 and 2021, respectively. The components of the provision for income taxes are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended December 31, 

 

​

    

2023

    

2022

    

2021

 

Current:

​

​

​

​

​

​

​

​

​

​

Federal

​

$

(317)

​

$

848

​

$

223

​

State

​

 

41

​

 

34

​

 

91

​

Foreign

​

 

(62)

​

 

918

​

 

3,119

​

Total current

​

 

(338)

​

 

1,800

​

 

3,433

​

Deferred:

​

​

​

​

​

​

​

​

​

​

Federal

​

 

(9)

​

 

(591)

​

 

(188)

​

State

​

​

(7)

​

​

(4)

​

​

(1)

​

Foreign

​

 

514

​

 

980

​

 

(2,151)

​

Total deferred

​

 

498

​

 

385

​

 

(2,340)

​

Total provision for income taxes

​

$

160

​

$

2,185

​

$

1,093

​

​

A reconciliation of the effective income tax rates and the U.S. statutory federal income tax rate is summarized below:

​

​

​

​

​

​

​

​

​

​

​

Year Ended December 31, 

 

​

    

2023

    

2022

    

2021

 

Statutory federal income tax rate

 

21.0

%  

21.0

%  

21.0

%  

State income taxes, net of federal tax benefits

 

(0.6)

​

0.1

​

0.4

​

Valuation allowance

 

(25.7)

​

(19.3)

​

(25.4)

​

Stock-based compensation

 

(1.7)

​

0.7

​

(3.2)

​

Foreign tax rate differential

​

6.1

​

(2.6)

​

(8.6)

​

Foreign tax incentives

​

0.1

​

(3.5)

​

(3.2)

​

Foreign income inclusion

​

—

​

18.9

​

10.4

​

Gain from sale of IP

​

—

​

—

​

16.9

​

Tax effect in equity method loss or gain from unconsolidated affiliates

​

0.4

​

(3.0)

​

(2.6)

​

Other

​

(0.4)

​

(1.8)

​

0.5

​

Effective tax rate

 

(0.8)

%  

10.5

%  

6.2

%  

​

Deferred tax assets and liabilities are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

As of December 31, 

 

​

    

2023

    

2022

 

Deferred tax assets:

​

​

​

​

​

​

​

Net operating loss carryforwards

​

$

14,362

​

$

9,571

​

Accruals, reserves and other

​

 

4,349

​

 

4,053

​

Credit carryforwards

​

 

325

​

 

206

​

Operating lease liability

​

 

206

​

 

60

​

Gross deferred tax assets

​

​

19,242

​

​

13,890

​

Valuation allowance

​

 

(17,462)

​

 

(11,885)

​

Total deferred tax assets

​

 

1,780

​

 

2,005

​

Deferred tax liabilities:

​

 

​

​

 

​

​

Operating lease right-of-use assets

​

 

(323)

​

 

(50)

​

Total net deferred tax assets (included in other assets)

​

$

1,457

​

$

1,955

​

​

As of December 31, 2023 we have federal net operating loss (“NOL”) carryforwards of approximately $40.2 million, which will begin to expire in 2025. We have California net operating loss carryforwards of approximately $115,000 as of December 31, 2023.

The deferred tax assets valuation allowance as of December 31, 2023 is attributed to U.S. federal, and state deferred tax assets, which result primarily from future deductible accruals, reserves, NOL carryforwards, and tax credit carryforwards. We believe that, based on a number of factors, the available objective evidence creates sufficient uncertainty regarding the realizability of the deferred tax assets such that a full valuation allowance has been recorded. These factors include our history of losses related to domestic operations, and the lack of carryback capacity to realize deferred tax assets. The valuation allowance increased for the year ended December 31, 2023 by $5.6 million and decreased $3.5 million for the year ended December 31, 2022.

The China Enterprise Income Tax Law (“EIT”) imposes a single uniform income tax rate of 25% on all Chinese enterprises. Our subsidiaries in China have qualified for a preferential 15% tax rate that is available for High and New Technology Enterprises (“HTE”). In order to retain the preferential tax rate, we must meet certain operating conditions, satisfy certain product requirements, meet certain headcount requirements and maintain certain levels of research expenditures. We realized benefits from this 10% reduction in tax rate of $47,000, $0.9 million and $1.0 million for 2023, 2022 and 2021, respectively. As of December 31, 2023, the favorable tax rate is still valid for the Company and it will stay the same for next year if there is no change of the business nature. The preferential tax rate that we enjoy could be modified or discontinued altogether at any time, which could materially and adversely affect our financial condition and results of operations.

Our subsidiaries in China also qualify for reduction in their taxable income in China for research and development (“R&D”) expenditures. Government pre-approval is required to claim R&D tax benefits. Any R&D claim is then submitted with the annual corporate income tax for the taxing authorities’ approval. Historically, we didn’t record such benefit until we received the tax refund from the Chinese government. Beginning in 2019, we record the tax benefit in the year it incurs the cost rather than in the year the tax benefit is received. This will better align the costs with the tax benefit. Our consolidated subsidiaries in China have enjoyed various tax holidays since 2000. Benefits under the tax holidays vary by jurisdiction.

Utilization of the NOL and R&D credit carryforwards may be subject to a substantial annual limitation due to ownership changes that might have occurred previously or that could occur in the future, as provided by Section 382 of the Internal Revenue Code of 1986 (“Section 382”), as well as similar state provisions. Ownership changes may limit the amount of NOL and tax credit carryforwards that can be utilized to offset future taxable income and tax, respectively. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain shareholders or public groups in the stock of a corporation by more than 50 percentage points over a three-year period. If there is a change of control, utilization of our NOL or tax credit carryforwards would be subject to an annual limitation under Section 382. Any limitation may result in expiration of a portion of the NOL or research and development credit carryforwards before utilization. Subsequent ownership changes could further impact the limitation in future years. Until a Section 382 study for the year-ended December 31, 2023 is completed and any limitation known, no amounts are being presented as an uncertain tax position. The Company does not believe that per Section 382 there will be a limitation on the utilization of the net operating loss and tax credit carryforwards. A full valuation allowance has been provided against our NOL carryforwards and R&D credit carryforwards and, if an adjustment is required, this adjustment would be offset by an adjustment to the valuation allowance. Thus, there would be no net impact to the consolidated balance sheets or statements of operations if an adjustment were required.

During fiscal year 2023 and 2022, the amount of gross unrecognized tax benefits was $1.1 million as of December 31, 2023 and 2022. The Company recognizes interest and penalties related to uncertain tax positions as part of the provision for income taxes. To date, such interest and penalties have not been material. All of the unrecognized tax benefit would impact the effective tax rate in future periods if recognized.

We comply with the laws, regulations, and filing requirements of all jurisdictions in which we conduct business. We regularly engage in discussions and negotiations with tax authorities regarding tax matters in various jurisdictions.

We file income tax returns in the U.S. federal, various states and foreign jurisdictions. Currently, there is no tax audit in any of the jurisdictions and we do not expect there will be any significant change to this.

On August 9, 2022, Congress passed the Creating Helpful Incentives to Produce Semiconductors (CHIPS) Act to strengthen domestic semiconductor manufacturing, design and research, fortify the economy and national security, and reinforce America’s chip supply chains. The CHIPS Act provides for a new 25% advanced manufacturing investment credit for investments in semiconductor manufacturing and for the manufacture of certain equipment required in the semiconductor manufacturing process. Since the Company has all its manufacturing in China, the Company will not qualify for the investment credit.

On August 16, 2022, President Biden signed the Inflation Reduction Act (IRA) into law. The law is intended to address inflation by paying down the national debt, lower consumer energy costs, provide incentives for the production of clean energy and reduce health care costs. The new law imposes a 1% excise tax on corporate buybacks, and a 15% minimum tax on the adjust financial statement income (AFSI) for corporations with average annual AFSI over a three-tax year period in excess of $1 billion. The Company does not anticipate the IRA to have a material impact on its financial statements.

v3.24.0.1
Net Income (Loss) per Share
 12 Months Ended
Dec. 31, 2023
Net Income (Loss) per Share  
Net Income (Loss) per Share

Note 13. Net Income (Loss) per Share

Basic net income (loss) per share is computed using the weighted average number of common shares outstanding during the periods less shares of common stock subject to repurchase and non-vested stock awards. Diluted

net income (loss) per share is computed using the weighted-average number of common shares outstanding and potentially dilutive common shares outstanding during the periods. The dilutive effect of outstanding stock options and restricted stock awards is reflected in diluted earnings per share by application of the treasury stock method. Potentially dilutive common shares consist of common shares issuable upon the exercise of stock options. Potentially dilutive common shares are excluded in net loss periods, as their effect would be anti-dilutive.

A reconciliation of the numerators and denominators of the basic and diluted net income per share calculations is as follows (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

Year ended

​

​

​

December 31, 

​

​

    

2023

    

2022

    

2021

 

Numerator:

​

​

​

​

​

​

​

​

​

​

Net income (loss) attributable to AXT, Inc.

​

$

(17,881)

​

$

15,811

​

$

14,575

​

Less: Preferred stock dividends

​

 

(177)

​

 

(177)

​

 

(177)

​

Net income (loss) available to common stockholders

​

$

(18,058)

​

$

15,634

​

$

14,398

​

Denominator:

​

​

​

​

​

​

​

​

​

​

Denominator for basic net income (loss) per share - weighted-average common shares

​

 

42,643

​

 

42,104

​

 

41,367

​

Effect of dilutive securities:

​

​

​

​

​

​

​

​

​

​

Common stock options

​

 

—

​

 

333

​

 

803

​

Restricted stock awards

​

 

—

​

 

278

​

 

550

​

Denominator for dilutive net income (loss) per common shares

​

 

42,643

​

 

42,715

​

 

42,720

​

Net income (loss) attributable to AXT, Inc. per common share:

​

​

​

​

​

​

​

​

​

​

Basic

​

$

(0.42)

​

$

0.37

​

$

0.35

​

Diluted

​

$

(0.42)

​

$

0.37

​

$

0.34

​

​

​

​

​

​

​

​

​

​

​

​

Options excluded from diluted net income (loss) per share as the impact is anti-dilutive

​

 

1,198

​

 

220

​

 

21

​

Restricted stock excluded from diluted net income (loss) per share as the impact is anti-dilutive

​

 

1,258

​

 

291

​

 

118

​

​
v3.24.0.1
Segment Information and Foreign Operations
 12 Months Ended
Dec. 31, 2023
Segment Information and Foreign Operations  
Segment Information and Foreign Operations

Note 14. Segment Information and Foreign Operations

Segment Information

We operate in one segment for the design, development, manufacture and distribution of high-performance compound and single element semiconductor substrates and sale of raw materials integral to these substrates. In accordance with ASC Topic 280, Segment Reporting, our chief operating decision-maker has been identified as the Chief Executive Officer, who reviews operating results to make decisions about allocating resources and assessing performance for the Company. Since we operate in one segment, all financial segment and product line information can be found in the consolidated financial statements.

Product Information

The following table represents revenue amounts (in thousands) by product type:

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

December 31, 

​

​

2023

    

2022

    

2021

 

Product Type:

​

​

​

​

​

​

​

​

​

Substrates

$

47,466

​

$

111,094

​

$

103,026

​

Raw materials and others

 

28,329

​

 

30,024

​

 

34,367

​

Total

$

75,795

​

$

141,118

​

$

137,393

​

​

Geographical Information

The following table represents revenue amounts (in thousands) reported for products shipped to customers in the corresponding geographic region:

​

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

​

December 31, 

​

 

​

2023

    

2022

    

2021

 

​

Geographical region:

​

​

​

​

​

​

​

​

​

​

China

$

39,778

​

$

55,414

​

$

67,394

​

​

Taiwan

​

8,651

​

​

28,780

​

​

16,841

​

​

Japan

​

4,641

​

​

11,724

​

​

10,112

​

​

Asia Pacific (excluding China, Taiwan and Japan)

​

3,814

​

​

4,188

​

​

7,540

​

​

Europe (primarily Germany)

​

12,315

​

​

20,592

​

​

23,069

​

​

North America (primarily the United States)

 

6,596

​

 

20,420

​

 

12,437

​

​

Total

$

75,795

​

$

141,118

​

$

137,393

​

​

Long-lived assets consist primarily of property, plant and equipment, and operating lease right-of-use assets are attributed to the geographic location in which they are located. Long-lived assets, net of depreciation, by geographic region were as follows (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

​

 

2023

    

2022

 

Long-lived assets by geographic region, net of depreciation:

​

​

​

​

​

​

​

North America

​

$

1,631

​

$

346

​

China

​

 

167,516

​

 

162,432

​

​

​

$

169,147

​

$

162,778

​

​
v3.24.0.1
Other income (expense), net
 12 Months Ended
Dec. 31, 2023
Other income (expense), net  
Other Income (expense), net

Note 15. Other income (expense), net

The components of other income (expense), net are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

December 31, 

​

​

2023

    

2022

    

2021

Foreign exchange gain (loss)

​

$

169

​

$

1,573

​

$

(434)

Income from local China government subsidy

​

​

2,557

​

​

1,710

​

​

1,125

Other income (expense)

​

​

(547)

​

​

204

​

​

(182)

​

​

$

2,179

​

$

3,487

​

$

509

​

​

​

​

​

​

​

​

​

​

​
v3.24.0.1
Commitments and Contingencies
 12 Months Ended
Dec. 31, 2023
Commitments and Contingencies  
Commitments and Contingencies

Note 16. Commitments and Contingencies

Legal Proceedings

From time to time we may be involved in judicial or administrative proceedings concerning matters arising in the ordinary course of business. We do not expect that any of these matters, individually or in the aggregate, will have a material adverse effect on our business, financial condition, cash flows or results of operations.

Leases

We lease certain equipment, office space, warehouse and facilities under long-term operating leases expiring at various dates through July 2029. The majority of our lease obligations relate to our lease agreement for our facility in Fremont, California with approximately 19,467 square feet, which was scheduled to expire in 2020. Under the terms of the facility lease agreement, in May 2020, we were granted an extension to the term of the lease for an additional three years. Furthermore, in September 2023, we entered into another agreement to extend the lease for an additional five years, commencing December 2023. There are no variable lease payments, residual value guarantees or any restrictions or covenants imposed by the facility lease. The remainder relate to our lease agreement for a nitrogen system to be used during the manufacturing process for our facility in Dingxing, China. The equipment lease became effective in August 2019 and will expire in July 2029. There are no variable lease payments, residual value guarantees or any restrictions or covenants imposed by the equipment lease. All other operating leases have a term of 12 months or less.

​

Leases are classified as either finance leases or operating leases. A lease is classified as a finance lease if any one of the following criteria are met: the lease transfers ownership of the asset by the end of the lease term, the lease contains an option to purchase the asset that is reasonably certain to be exercised, the lease term is for a major part of the remaining useful life of the asset or the present value of the lease payments equals or exceeds substantially all of the fair value of the asset. A lease is classified as an operating lease if it does not meet any one of these criteria. All of our leases are classified as operating leases and substantially all of our operating leases are comprised of equipment and office space leases. None of our leases are classified as, finance leases.

​

For all leases at the lease commencement date, a right-of-use asset and a lease liability are recognized. The right-of-use asset represents the right to use the leased asset for the lease term. The lease liability represents the present value of the lease payments under the lease.

​

The right-of-use asset is initially measured at cost, which primarily comprises the initial amount of the lease liability, plus any initial direct costs incurred, consisting mainly of brokerage commissions, less any lease incentives received. All right-of-use assets are reviewed for impairment. The lease liability is initially measured at the present value of the lease payments, discounted using the interest rate implicit in the lease or, if that rate cannot be readily determined, our secured incremental borrowing rate for the same term as the underlying lease.

​

Lease payments included in the measurement of the lease liability comprise the following: the fixed noncancelable lease payments, payments for optional renewal periods where it is reasonably certain the renewal period will be exercised, and payments for early termination options unless it is reasonably certain the lease will not be terminated early.

​

Lease expense for operating leases consists of the lease payments plus any initial direct costs, primarily brokerage commissions, and is recognized on a straight-line basis over the lease term.

​

We have elected not to recognize right-of-use assets and lease liabilities for short-term leases that have a term of 12 months or less. The effect of short-term leases on our right-of-use asset and lease liability was not material.

​

As of December 31, 2023, the maturities of our operating lease liabilities (excluding short-term leases) are as follows (in thousands):

​

​

​

Maturity of Lease Liabilities

    

​

2024

$

591

2025

​

604

2026

​

618

2027

​

633

2028

​

614

Thereafter

​

153

Total minimum lease payments

​

3,213

Less: Interest

​

(404)

Present value of lease obligations

​

2,809

Less: Current portion, included in accrued liabilities

​

(458)

Long-term portion of lease obligations

$

2,351

​

The weighted average remaining lease term and the weighted-average discount rate for our operating leases are as follows:

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

​

​

2023

​

2022

​

Weighted-average remaining lease term (years)

​

5.22

​

5.89

​

Weighted-average discount rate

​

5.14

%

4.61

%

​

Supplemental cash flow information related to leases where we are the lessee is as follows (in thousands):

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

​

December 31, 

​

​

​

2023

​

2022

​

Cash paid for amounts included in the measurement of lease liabilities:

​

​

​

​

​

​

​

Operating cash flows from operating leases

​

$

578

​

$

574

​

​

The components of lease expense are as follows (in thousands) within our consolidated statements of operations:

​

​

​

​

​

​

​

​

​

Year Ended

​

​

December 31, 

​

​

2023

​

2022

Operating lease

​

$

548

​

$

530

Short-term lease expense

​

​

143

​

​

137

Total

​

$

691

​

$

667

​

Royalty Agreement

In 2020, we and a competitor entered into a cross license and covenant agreement (the “Cross License Agreement”), which has a term that began on January 1, 2020 and expires on December 31, 2029. The Cross License Agreement is a fixed-cost cross license and not a variable-cost cross license that is based on revenue or units. Under the Cross License Agreement, we are obligated to make annual payments over a 10-year period. For the years ended December 31, 2023 and 2022, the royalty expense under the Cross License Agreement was not considered material to our consolidated financial statements.

​

​

​

Land Purchase and Investment Agreement

 

We have established a wafer process production line in Dingxing, China. In addition to a land rights and building purchase agreement that we entered into with a private real estate development company to acquire our new manufacturing facility, we also entered into a cooperation agreement with the Dingxing local government. In addition to pledging its full support and cooperation, the Dingxing local government will issue certain credits or rebates to us as we achieve certain milestones. We, in turn, agreed to hire local workers over time, pay taxes when due and eventually demonstrate a total investment of approximately $90 million in value, assets and capital. The investment will include cash paid for the land and buildings, cash on deposit in our name at local banks, the gross value of new and used equipment (including future equipment that might be used for indium phosphide and germanium substrates production), the deemed value for our customer list or the end user of our substrates, for example, the end users of 3-D sensing VCSELs (vertical cavity surface emitting lasers), a deemed value for employment of local citizens, a deemed value for our proprietary process technology, other intellectual property, other intangibles and additional items of value. There is no timeline or deadline by which this must be accomplished, rather it is a good faith covenant entered into between AXT and the Dingxing local government.  Further, there is no specific penalty contemplated if either party breaches the agreement. However, the agreement does state that each party has a right to seek from the other party compensation for losses. Under certain conditions, the Dingxing local government may purchase the land and building at the appraised value. We believe that such cooperation agreements are normal, customary and usual in China and that the future valuation is flexible. We have a similar agreement with the city of Kazuo, China, although on a smaller scale. The total investment targeted by AXT in Kazuo is approximately $15 million in value, assets and capital. In addition, BoYu has a similar agreement with the city of Kazuo. The total investment targeted by BoYu in Kazuo is approximately $8 million in value, assets and capital.
v3.24.0.1
Unaudited Quarterly Consolidated Financial Data
 12 Months Ended
Dec. 31, 2023
Unaudited Quarterly Consolidated Financial Data  
Unaudited Quarterly Consolidated Financial Data

Note 17. Unaudited Quarterly Consolidated Financial Data

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Quarter

 

​

    

First

    

Second

    

Third

    

Fourth

 

​

​

(in thousands, except per share data)

 

2023:

​

​

​

​

​

​

​

​

​

​

​

​

​

Revenue

​

$

19,405

​

$

18,595

​

$

17,366

​

$

20,429

​

Gross profit

​

 

5,110

​

 

1,715

​

 

1,866

​

 

4,627

​

Net income attributable to AXT, Inc.

​

 

(3,348)

​

 

(5,089)

​

 

(5,823)

​

 

(3,621)

​

Net income attributable to AXT, Inc. per share, basic

​

$

(0.08)

​

$

(0.12)

​

$

(0.14)

​

$

(0.09)

​

Net income attributable to AXT, Inc. per share, diluted

​

$

(0.08)

​

$

(0.12)

​

$

(0.14)

​

$

(0.09)

​

2022:

​

​

​

​

​

​

​

​

​

​

​

​

​

Revenue

​

$

39,653

​

$

39,487

​

$

35,183

​

$

26,795

​

Gross profit

​

 

13,308

​

 

15,435

​

 

14,782

​

 

8,596

​

Net income (loss) attributable to AXT, Inc.

​

 

3,165

​

 

5,546

​

 

5,759

​

 

1,341

​

Net income (loss) attributable to AXT, Inc. per share, basic

​

$

0.07

​

$

0.13

​

$

0.14

​

$

0.03

​

Net income (loss) attributable to AXT, Inc. per share, diluted

​

$

0.07

​

$

0.13

​

$

0.13

​

$

0.03

​

​
v3.24.0.1
Redeemable Noncontrolling Interests
 12 Months Ended
Dec. 31, 2023
Redeemable Noncontrolling Interests  
Redeemable Noncontrolling Interests

Note 18. Redeemable Noncontrolling Interests

As discussed in Note 1, during the quarter ended December 31, 2020, Tongmei entered into the Capital Investment Agreements with Investors that invested approximately $48.1 million in the form of redeemable noncontrolling interests representing 7.06% of the outstanding shares of Tongmei. An additional investment of approximately $1.5 million of new capital was funded in early January 2021. Under China regulations these investments must be formally approved by the appropriate government agency and are not deemed to be dilutive until such approval is granted. The government approved the entire approximately $49 million investment on January 25, 2021, at which time the Investors owned a redeemable noncontrolling interest in Tongmei of 7.28%. The initial carrying amount of the redeemable noncontrolling interest was recorded at fair value on the date of issuance of Tongmei’s common stock, net of issuance costs and presented in temporary equity on the consolidated balance sheets. This classification is due to the existence of certain contingencies that could result in potential redemption at the fixed purchase price as described below. We currently do not believe that this is probable thus no amortization of the issuance costs has been recorded.

Pursuant to the Capital Investment Agreements with the Investors, each Investor has the right to require AXT to redeem any or all Tongmei shares held by such Investor at the original purchase price paid by such Investor, without interest, in the event the IPO fails to pass the audit of the Shanghai Stock Exchange, is not approved by the Chinese Securities Regulatory Commission (“CSRC”) or Tongmei cancels the IPO application. The aggregate redemption amount is approximately $49 million, subject to the foreign exchange rate variable at time of redemption.

Tongmei submitted its IPO application to the Shanghai Stock Exchange in December 2021 and it was formally accepted for review on January 10, 2022. The Shanghai Stock Exchange approved the IPO application on July 12, 2022. On August 1, 2022, the CSRC accepted for review Tongmei’s IPO application. The STAR Market IPO remains subject to review and approval by the CSRC and other authorities. The process of going public on the STAR Market includes several periods of review and, therefore, is a lengthy process. Subject to review and approval by the CSRC and other authorities, Tongmei hopes to accomplish this goal in the coming months. The listing of Tongmei on the STAR Market will not change the status of AXT as a U.S. public company.

The components of the change in redeemable noncontrolling interests for the years ended December 31, 2023 and 2022 are presented in the following table (in thousands):

​

​

​

Balance as of January 1, 2022

$

50,385

Investment in subsidiary with redeemable noncontrolling interest

​

471

Equity issuance costs incurred

​

(2,699)

Stock-based compensation attributable to redeemable noncontrolling interests

​

(36)

Net income attributable to redeemable noncontrolling interests

​

1,598

Effect of foreign currency translation on redeemable noncontrolling interests

​

(3,962)

Effect of foreign currency translation attributable to redeemable noncontrolling interests

​

(911)

Balance as of December 31, 2022

​

44,846

Investment in subsidiary with redeemable noncontrolling interest

​

155

Equity issuance costs incurred

​

(880)

Stock-based compensation attributable to redeemable noncontrolling interests

​

52

Net loss attributable to redeemable noncontrolling interests

​

(920)

Effect of foreign currency translation on redeemable noncontrolling interests

​

(1,260)

Effect of foreign currency translation attributable to redeemable noncontrolling interests

​

(330)

Balance as of December 31, 2023

$

41,663

​
v3.24.0.1
Subsequent Events
 12 Months Ended
Dec. 31, 2023
Subsequent Events  
Subsequent Events

Note 19. Subsequent Events

In January and February 2024, the Company obtained a total of $7.9 million in new one-year bank loans with interest rates ranging from 3.0% to 4.3%. The $5.1 million of the new bank loans are unsecured, while the remaining

$2.8 million was collateralized by a ChaoYang LiMei time deposit. The Company repaid $14.5 million of existing loans In January and February 2024.

In January 2024, the Company secured a new line of credit amounting to $9.9 million, structured as a five-year bank loan. The credit facility bears an interest rate of 6.5% on the amount drawn from the line of credit. The credit facility is collateralized by the real estate properties owned by ChaoYang Tongmei. In January 2024, the Company borrowed $5.9 million against the credit facility. The primary intended use of the credit facility is for construction projects.

In January, February and March 2024, our consolidated subsidiaries, collectively, received approximately $715,000 in subsidies from the Chinese government. These funds are designated to support digital projects within enterprises and initiatives aimed at waste recycling, etc.

​
v3.24.0.1
The Company and Summary of Significant Accounting Policies (Policies)
 12 Months Ended
Dec. 31, 2023
The Company and Summary of Significant Accounting Policies  
Principles of Consolidation

Principles of Consolidation

The consolidated financial statements include the accounts of AXT, and our consolidated subsidiaries, Beijing Tongmei Xtal Technology Co., Ltd. (“Tongmei”), AXT-Tongmei, Inc. (“AXT-Tongmei”), Baoding Tongmei Xtal Technology Co., Ltd. (“Baoding Tongmei”), ChaoYang Tongmei Xtal Technology Co., Ltd. (“ChaoYang Tongmei”), ChaoYang LiMei Semiconductor Technology Co., Ltd. (“ChaoYang LiMei”), ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd. (“ChaoYang XinMei”), Nanjing JinMei Gallium Co., Ltd. (“JinMei”), ChaoYang JinMei Gallium Ltd. (“ChaoYang JinMei”), ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd. (“ChaoYang ShuoMei”), MaAnShan JinMei Gallium Ltd., (“MaAnShan JinMei”) and Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd. (“BoYu”). Baoding Tongmei is located in the city of Dingxing, China. Each of ChaoYang Tongmei and ChaoYang LiMei is located in the city of Kazuo, China. All significant inter-company accounts and transactions have been eliminated. Investments in business entities in which we do not have controlling interests, but have the ability to exercise significant influence over operating and financial policies (generally 20-50% ownership), are accounted for by the equity method. For the years ended 2023 and 2022, we have three and six companies accounted for by the equity method, respectively. For the majority-owned subsidiaries that we consolidate, we reflect the portion we do not own as either noncontrolling interests in stockholder’s equity or as redeemable noncontrolling interests in temporary equity on our consolidated balance sheets and in our consolidated statements of operations.

​

When market conditions are warranted, we intend to construct facilities at the ChaoYang LiMei location to provide us with additional production capacity. For the years ended 2023 and 2022, expenses associated with ChaoYang LiMei had a de minimis impact on our consolidated financial statements.

​

In February 2021, Tongmei signed a joint venture agreement with certain investors to fund a new company, ChaoYang XinMei. The agreement called for a total investment of approximately $3.0 million, of which Tongmei would fund approximately $1.8 million for a 58.5 percent ownership of ChaoYang XinMei. In February 2021, the investors completed the initial funding of approximately $1.5 million. Tongmei’s portion of the investment was approximately $0.9 million. In May 2021, the investors completed the funding of the remaining balance of approximately $1.5 million. Tongmei’s portion of the final investment was approximately $0.9 million, for a total investment of approximately $1.8 million for a 58.5 percent ownership of ChaoYang XinMei. In September 2021 and October 2021, ChaoYang XinMei received funding from a minority investor of $0.9 million and $1.0 million, respectively. In December 2021 and January 2022, ChaoYang XinMei received funding from Tongmei of $1.4 million and $1.4 million, respectively. In January 2022, the China local government certified this additional funding in ChaoYang XinMei as an equity investment. Tongmei’s ownership remained at 58.5% after these equity investments. In April 2022, Tongmei entered into a capital increase agreement (the “Capital Increase Agreement”) with minority investors to further invest $4.5 million in ChaoYang XinMei. Tongmei’s portion of the investment was approximately $2.6 million, of which $1.1 million was invested in April 2022 and $0.8 million was invested in May 2022. The minority investors’ portion of the investment was approximately $1.9 million, of which $0.7 million was invested in April 2022 and $0.6 million was invested in May 2022. As a result, noncontrolling interests increased $1.4 million and redeemable noncontrolling interests increased $0.1 million. Tongmei’s ownership remained at 58.5% after the April 2022 and May 2022 equity investments. In July 2022, Tongmei and the minority investors further invested $0.8 million and $0.6 million in ChaoYang XinMei, respectively. This completed the investment obligations under the Capital Increase Agreement. As a result, noncontrolling interests increased $610,000 and redeemable noncontrolling interests increased $57,000. Tongmei’s ownership remained at 58.5% after the July 2022 equity investment.

​

In April 2022, ChaoYang JinMei signed a joint venture agreement with a certain investor to fund a new company, ChaoYang ShuoMei, our consolidated subsidiary. The agreement calls for a total investment of approximately $4.4 million, of which ChaoYang JinMei will fund approximately $3.3 million for a 75 percent ownership of ChaoYang ShuoMei. In July and August 2022, ChaoYang JinMei completed the initial funding of $1.0 million in ChaoYang ShuoMei. In August 2022, the investor invested $334,000 in ChaoYang ShuoMei. As a result, noncontrolling interests increased $406,000 and redeemable noncontrolling interests increased $73,000. In January 2023, ChaoYang ShuoMei received $0.5 million in funding from ChaoYang JinMei and $0.2 million in funding from one of the minority investors. As a result, noncontrolling interests increased $0.2 million and redeemable noncontrolling interests increased $36,000. In May 2023, ChaoYang ShuoMei received $1.0 million in funding from ChaoYang JinMei and $0.3 million in funding from one of the minority investors. As a result, noncontrolling interests increased $0.4 million and redeemable noncontrolling interests increased $75,000. In August 2023, ChaoYang ShuoMei received $0.6 million in funding from ChaoYang JinMei and $0.2 million in funding from one of the minority investors. As a result, noncontrolling interests increased $0.2 million and redeemable noncontrolling interests increased $44,000. ChaoYang JinMei has completed its investment obligations under the ChaoYang ShuoMei Joint Venture Agreement. ChaoYang JinMei’s ownership of ChaoYang ShuoMei remained at 75% after these equity investments.

​

In April 2022, Tongmei signed a joint venture agreement with certain investors to fund a new company, ChaoYang KaiMei. The agreement called for a total investment of approximately $7.6 million, of which Tongmei would fund approximately $3.0 million for a 40.0 percent ownership of ChaoYang KaiMei. In July 2022, the investors completed the initial funding of approximately $2.2 million. Tongmei’s portion of the investment was approximately $0.9 million. In January 2023, Tongmei made an investment of $0.9 million to ChaoYang KaiMei. In each of July 2023 and August 2023, Tongmei made an investment of approximately $0.6 million in ChaoYang KaiMei. These contributions culminated in the fulfillment of all of Tongmei’s financial obligations under the April 2022 ChaoYang KaiMei Joint Venture Agreement. In September 2023, Tongmei entered into another joint venture agreement with the same group of investors. This new agreement called for additional investment of approximately $5.6 million, with Tongmei committing to fund approximately $2.3 million. In December 2023, Tongmei made its initial additional investment of approximately $0.6 million in ChaoYang KaiMei. Tongmei’s ownership of ChaoYang KaiMei remained at 40% after these equity investments.

​

All activities for MaAnShan JinMei ceased during the first half of 2022 and the subsidiary was subsequently dissolved in May 2022. The dissolution of MaAnShan JinMei had a de minimis impact on the consolidated results.

​

During the quarter ended December 31, 2020, Tongmei entered into two sets of definitive transaction documents, each consisting of a capital increase agreement along with certain supplemental agreements in substantially the same form (collectively, the “Capital Increase Agreements”), with several private equity investors in China.

​

In preparation for Tongmei’s application for a listing of shares in an initial public offering (the “IPO”) on the Shanghai Stock Exchange’s Sci-Tech innovAtion boaRd (the “STAR Market”), in late December 2020, we reorganized our entity structures in China. JinMei and BoYu and its subsidiaries were assigned to Tongmei and effectively merged with Tongmei although they retained their own respective legal entity status and are wholly owned subsidiaries of Tongmei. The 33% minority interest stakeholders of BoYu converted their ownership to a 7.59% minority interest in Tongmei. The 8.5% minority interest stakeholders, employees of JinMei, converted their ownership to a 0.38% minority interest in Tongmei. Further, a number of employees, key managers and contributors purchased a 0.4% minority interest in Tongmei. Additionally, Baoding Tongmei and ChaoYang Tongmei, were assigned to Tongmei as wholly owned subsidiaries. In 2020, the private equity funds (the “Investors”) had transferred approximately $48.1 million of new capital to Tongmei. An additional investment of approximately $1.5 million of new capital was funded in January 2021. Under China regulations these investments must be formally approved by the appropriate government agency and are not deemed to be dilutive until such approval is granted. The government approved the approximately $49 million investment in its entirety on January 25, 2021, at which time the Investors owned a redeemable noncontrolling interest in Tongmei of 7.28%. As of September 30, 2022, Tongmei’s noncontrolling interests and redeemable noncontrolling interests totaled approximately 14.5%. AXT remains the controlling stakeholder of Tongmei and holds a majority of the board of director positions of Tongmei. In June 2021, AXT sold AXT-Tongmei to Tongmei for $1. Since Tongmei is 85.5% owned by AXT, and the transaction was between common interest holders, the transaction was accounted for at net book value and resulted in an increase of $1.2 million to noncontrolling interests and $1.2 million to redeemable noncontrolling interests.

Use of Estimates

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires management to make estimates, judgments and assumptions. We believe that the estimates, judgments, and assumptions upon which management relies are reasonable based on information available at the time that these estimates, judgments, and assumptions are made. These estimates, judgments, and assumptions can affect the reported amounts of assets and liabilities as of the date of the consolidated financial statements as well as the reported amounts of revenues and expenses during the periods presented. To the extent there are material differences between these estimates and actual results, our consolidated financial statements would be affected.
Fair Value of Financial Instruments

Fair Value of Financial Instruments

The carrying amounts of certain of our financial instruments including cash and cash equivalents, restricted cash, short-term investments and long-term investments, accounts receivable, accounts payable, accrued liabilities and bank loans approximate fair value due to their short maturities. Certain cash equivalents and investments are required to be adjusted to fair value on a recurring basis. See Note 2.
Fair Value of Investments

Fair Value of Investments

ASC Topic 820, Fair value measurement (“ASC 820”) establishes three levels of inputs that may be used to measure fair value.

Level 1 instruments represent quoted prices in active markets. Therefore, determining fair value for Level 1 instruments does not require significant management judgment, and the estimation is not difficult.

Level 2 instruments include observable inputs other than Level 1 prices, such as quoted prices for similar instruments in markets with insufficient volume or infrequent transactions (less active markets), issuer bank statements, credit ratings, non-binding market consensus prices that can be corroborated with observable market data, model-derived valuations in which all significant inputs are observable or can be derived principally from or corroborated with observable market data for substantially the full term of the assets or liabilities, or quoted prices for similar assets or liabilities. These Level 2 instruments require more management judgment and subjectivity compared to Level 1 instruments, including:

●Determining which instruments are most comparable to the instrument being priced requires management to identify a sample of similar securities based on the coupon rates, maturity, issuer, credit rating, and instrument type, and subjectively select an individual security or multiple securities that are deemed most similar to the security being priced.
●Determining which model-derived valuations to use in determining fair value requires management judgment. When observable market prices for similar securities or comparable securities are not available, we price our marketable debt instruments using non-binding market consensus prices that are corroborated with observable market data or pricing models, such as discounted cash flow models, with all significant inputs derived from or corroborated with observable market data.

Level 3 instruments include unobservable inputs to the valuation methodology that are significant to the measurement of fair value of assets or liabilities. The determination of fair value for Level 3 instruments requires the most management judgment and subjectivity.

We place short-term foreign currency hedges that are intended to offset the potential cash exposure related to fluctuations in the exchange rate between the United States dollar and Japanese yen. We measure the fair value of these foreign currency hedges at each month end and quarter end using current exchange rates and in accordance with generally accepted accounting principles. At quarter end any foreign currency hedges not settled are netted in “Accrued liabilities” on the consolidated balance sheets and classified as Level 3 assets and liabilities. As of December 31, 2023 and 2022, the net change in fair value from the placement of the hedge to settlement had a de minimis impact to the consolidated results.
Foreign Currency Translation

Foreign Currency Translation

The functional currency of our Chinese subsidiaries is the renminbi, the local currency of China. Transaction gains and losses resulting from transactions denominated in currencies other than the U.S. dollar or in the functional currencies of our subsidiaries are included in “Other income, net” for the years presented. The transaction gain totaled $0.2 million and $1.6 million for the years ended December 31, 2023 and 2022, respectively. The transaction loss for the year ended December 31, 2021 totaled $434,000. The assets and liabilities of the subsidiaries are translated at the rates of exchange on the balance sheet date. Revenue and expense items are translated at the average rate of exchange for the period. Gains and losses from foreign currency translation are included in “Other comprehensive income (loss)”, net of tax in the consolidated statements of comprehensive income (loss).
Revenue Recognition

Revenue Recognition

We manufacture and sell high-performance compound semiconductor substrates including indium phosphide, gallium arsenide and germanium wafers, and our consolidated subsidiaries sell certain raw materials, including high purity gallium (6N and 7N Ga), pyrolytic boron nitride (pBN) crucibles and boron oxide (B2O3). After we ship our products, there are no remaining obligations or customer acceptance requirements that would preclude revenue recognition. Our products are typically sold pursuant to purchase orders placed by our customers, and our terms and conditions of sale do not require customer acceptance. We account for a contract with a customer when there is a legally enforceable contract, which could be the customer’s purchase order, the rights of the parties are identified, the contract has commercial terms, and collectibility of the contract consideration is probable. The majority of our contracts have a single performance obligation to transfer products and are short term in nature, usually less than six months. Our revenue is measured based on the consideration specified in the contract with each customer in exchange for transferring

products that are generally based upon a negotiated formula, list or fixed price. Revenue is recognized when control of the promised goods is transferred to our customer, which is either upon shipment from our dock, receipt at the customer’s dock, or removal from consignment inventory at the customer’s location, in an amount that reflects the consideration we expect to be entitled to receive in exchange for those goods.

​

We have elected to account for shipping and handling as activities to fulfill the promise to transfer the goods. Shipping and handling fees billed to customers in a sales transaction are recorded as an offset to shipping and handling expenses. Sales taxes and value added taxes in foreign jurisdictions that are collected from customers and remitted to governmental authorities are accounted for on a net basis and, therefore, are excluded from revenue.

​

We do not provide training, installation or commissioning services. We provide for future returns based on historical data, prior experience, current economic trends and changes in customer demand at the time revenue is recognized. We do not recognize any asset associated with the incremental cost of obtaining revenue generating customer contracts. As such, sales commissions are expensed as incurred, given that the expected period of benefit is less than one year.

 

Contract Balances

 

We receive payments from customers based on a billing schedule as established in our contracts. Contract assets are recorded when we have a conditional right to consideration for our completed performance under the contracts. Accounts receivables are recorded when the right to this consideration becomes unconditional. We do not have any material contract assets as of December 31, 2023, or 2022.

​

​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31,

​

​

​

2023

​

2022

​

Contract liabilities

​

$

305

​

$

338

​

During the three and twelve months ended December 31, 2023, the Company recognized $9,000 and $287,000, respectively, of revenue that was included in the contract balances as of December 31, 2022. During the three and twelve months ended December 31, 2022, the Company recognized $22,000 and $760,000 of revenue that was included in the contract balances as of December 31, 2021.

​

​

​

​

​

​

​

​

Disaggregated Revenue

 

In general, revenue disaggregated by product types and geography (See Note 14) is aligned according to the nature and economic characteristics of our business and provides meaningful disaggregation of our results of operations. Since we operate in one segment, all financial segment and product line information can be found in the consolidated financial statements.

 

Practical Expedients and Exemptions

 

We elected to use the following practical expedients: (i) not to adjust the promised amount of consideration for the effects of a significant financing component when we expect, at contract inception, that the period between our transfer of a promised product or service to a customer and when the customer pays for that product or service will be one year or less; (ii) to expense costs as incurred for costs to obtain a contract when the amortization period would have been one year or less; (iii) not to assess whether promised goods or services are performance obligations if they are immaterial in the context of the contract with the customer.

 

In addition, we do not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less.
Accounting for Sales and Use Taxes

Accounting for Sales and Use Taxes

We record sales taxes collected on sales of our products and for amounts not yet remitted to tax authorities as accrued liabilities on our consolidated balance sheets.

Risks and Concentration of Credit Risk

Risks and Concentration of Credit Risk

Our business is very dependent on the semiconductor, lasers and optical industries which can be highly cyclical and experience downturns as a result of economic changes, overcapacity, and technological advancements. Significant technological changes in the industry or customer requirements, or the emergence of competitive products with new capabilities or technologies, could adversely affect our operating results. In addition, a significant portion of our revenues and net income is derived from international sales. Fluctuations of the United States dollar against foreign currencies and changes in local regulatory or economic conditions, particularly in an emerging market such as China, could adversely affect operating results.

We depend on a limited number of suppliers for certain raw materials, components and equipment used in manufacturing our products, including quartz tubing and polishing solutions. We generally purchase these materials through standard purchase orders and not pursuant to long-term supply contracts.

Financial instruments that potentially subject us to concentration of credit risk consist primarily of cash and cash equivalents, investments, and accounts receivable. We invest primarily in money market accounts, certificates of deposit and corporate bonds. The composition and maturities are regularly monitored by management. Such deposits are in excess of the amount of the insurance provided by the federal government on such deposits. We are exposed to credit risks in the event of default by the issuers to the extent of the amount recorded on the consolidated balance sheets.

​

We perform ongoing credit evaluations of our customers’ financial condition, and limit the amount of credit extended when deemed necessary, but generally do not require collateral. The credit risk in our accounts receivable is mitigated by our credit evaluation process and the geographical dispersion of sales transactions. No customer accounted for more than 10% of our accounts receivable as of December 31, 2023 and two customers accounted for more than 10% of our accounts receivable as of December 31, 2022.

No customer represented 10% of our revenue for the year ended December 31, 2023 and 2021. One customer represented 15% of our revenue for the year ended December 31, 2022. Our top five customers, although not the same five customers for each period, represented 25% of our revenue for the year 2023, 34% of our revenue for the year 2022, and 26% of our revenue for the year 2021.

For the year ended December 31, 2023, two third-party customers for the raw materials products from our consolidated subsidiaries accounted for over 10% of the revenue from raw materials sales. For the years ended December 31, 2022 and 2021, one third-party customer for the raw materials products from our consolidated subsidiaries accounted for over 10% of the revenue from raw materials sales. Our subsidiaries and raw material joint ventures are a key strategic benefit for us as they further diversify our sources of revenue.
Cash and Cash Equivalents

Cash and Cash Equivalents

We consider investments in highly liquid instruments purchased with an original maturity of three months or less to be cash equivalents. Cash equivalents consist primarily of certificate of deposits. Cash and cash equivalents are stated at cost, which approximates fair value.

Restricted Cash

Restricted Cash

​

We maintain restricted cash in connection with cash balances temporarily restricted for regular business operations. In May 2022, Tongmei and the Bank of Beijing signed a credit facility for $3.4 million. As a condition of the credit facility we must maintain a time deposit at the Bank of Beijing as collateral, and therefore we placed time deposits of $2.9 million and $1.0 million at the Bank of Beijing in April 2022 and May 2022, respectively. In December 2022, we

placed another time deposit of $2.5 million at the Bank of Beijing as collateral for a bank loan of $2.3 million received by Tongmei in January 2023. In January 2023, our consolidated subsidiary, ChaoYang LiMei, placed a time deposit of $3.0 million at the Bank of China as collateral for a bank loan of $2.9 million received by Tongmei in January 2023. When the May 2022 bank loan under the credit facility matured, we utilized the same time deposit of $3.9 million as collateral for a new bank loan of $3.5 million from the Bank of Beijing in June 2023. Furthermore, during June 2023 and December 2023, time deposits of $1.5 million each were placed at the Bank of Beijing as collateral for two bank loans of $1.4 million each received by Tongmei. Each of the bank loans has a term of 12 months. Therefore, the January 2023 bank loans, the June 2023 bank loans, and the December 2023 bank loan, along with the respective time deposits, are classified as short-term investments in our consolidated balance sheets. The time deposits have been excluded from the Company’s cash and cash equivalents balance. As of December 31, 2023, $12.4 million was included in restricted cash in our consolidated balance sheets.
Short-Term and Long-Term Investments

Short-Term and Long-Term Investments

We classify our investments in marketable securities as available-for-sale debt securities. Short-term and long-term investments are comprised of available-for-sale marketable securities, which consist primarily of certificates of deposit and corporate bonds. These investments are reported at fair value as of the respective balance sheet dates with unrealized gains and losses included in accumulated other comprehensive income (loss) within stockholders’ equity on the consolidated balance sheets. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization is included in “Other income, net” in the consolidated statements of operations. Realized gains and losses and declines in value judged to be other than temporary on available-for-sale securities are also included in “Other income, net” in the consolidated statements of operations. The cost of securities sold is based upon the specific identification method.
Accounts Receivable and Allowance for Doubtful Accounts and Sales Returns

Accounts Receivable and Allowance for Credit Losses and Sales Returns

Accounts receivable are recorded at the invoiced amount and are not interest bearing. We review at least quarterly, or when there are changes in credit risks, the likelihood of collection on our accounts receivable balances and provide an allowance for credit losses. We measure the expected credit losses on a collective (pool) basis when similar delinquency status exist. We evaluate receivables from U.S. customers with an emphasis on balances in excess of 90 days and for receivables from customers located outside the U.S. with an emphasis on balances in excess of 120 days and establish a reserve allowance on the receivable balances if needed. The reason for the difference in the evaluation of receivables between foreign and U.S. customers is that U.S. customers have historically made payments in a shorter period of time than foreign customers. Foreign business practices generally require us to allow customer payment terms that are longer than those accepted in the United States.

In accordance with ASC 326-20’s current expected credit loss impairment model, we exercise judgment when determining the adequacy of these reserves as we evaluate historical bad debt trends, general economic conditions in the United States and internationally, and reasonable and supportable forecasts of future economic conditions. Uncollectible receivables are recorded as provision for credit losses when a credit loss is expected through the establishment of an allowance, which would then be written off when all efforts to collect have been exhausted and recoveries are recognized when they are received. As of December 31, 2023 and 2022, our accounts receivable, net balance was $19.3 million and $29.3 million, respectively, which was net of an allowance for credit losses of $579,000 and $307,000 as of December 31, 2023 and 2022, respectively. During 2023, we increased the allowance for credit losses by $272,000. During 2022, we increased the allowance for credit losses by $177,000. If actual uncollectible accounts differ substantially from our estimates, revisions to the estimated allowance for credit losses would be required, which could have a material impact on our financial results for the future periods.

As of December 31, 2023 and 2022, the sales returns reserve (included in accrued liabilities) balance was $39,000 and $112,000, respectively. During 2023, we utilized $39,000 and reduced an additional $34,000 and during 2022, we utilized $112,000 and reserved an additional $176,000.

Warranty Reserve

Warranty Reserve

We maintain a warranty reserve based upon our claims experience during the prior twelve months and any pending claims and returns of which we are aware. Warranty costs are accrued at the time revenue is recognized. As of December 31, 2023 and 2022, accrued product warranties totaled $703,000 and $669,000, respectively. The increase in accrued product warranties is primarily attributable to increased claims for quality issues experienced by some of our customers. If actual warranty costs or pending new claims differ substantially from our estimates, revisions to the estimated warranty liability would be required, which could have a material impact on our financial condition and results of operations for future periods.
Inventories

Inventories

Inventories are stated at the lower of cost (approximated by standard cost) or net realizable value. Cost is determined using the weighted average cost method. Our inventory consists of raw materials as well as finished goods and work-in-process that include material, labor and manufacturing overhead costs. We routinely evaluate the levels of our inventory in light of current market conditions in order to identify excess and obsolete inventory, and we provide a reserve for certain inventories to their estimated net realizable value based upon the age and quality of the product and the projections for sale of the completed products. When a reserve is recorded, a new lower cost basis for that inventory is established and subsequent changes in facts and circumstances do not result in the restoration or increase in the new cost basis.

Property, Plant and Equipment

Property, Plant and Equipment

Property, plant and equipment are stated at cost less accumulated depreciation computed using the straight-line method over the estimated economic lives of the assets, which vary from 1 to 39.5 years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life or the term of the lease. We generally depreciate computer, software, office equipment, furniture and fixtures over 3 to 5 years, machinery and equipment over 1 to 20 years, automobiles over 5 to 10 years, leasehold and building improvements over 10 years, or the lease term if shorter, and buildings over 39.5 years. Repairs and maintenance costs are expensed as incurred.
Impairment of Long-Lived Assets

Impairment of Long-Lived Assets

We evaluate property, plant and equipment and intangible assets for impairment. When events and circumstances indicate that long-lived assets may be impaired, we compare the carrying value of the long-lived assets to the projection of future undiscounted cash flows attributable to these assets. In the event that the carrying value exceeds the future undiscounted cash flows, we record an impairment charge against income equal to the excess of the carrying value over the assets’ fair value. Fair values are determined based on quoted market values, discounted cash flows or internal and external appraisals, as applicable. We did not recognize any impairment charges of long-lived assets in 2023, 2022 and 2021.
Impairment of Investments

Impairment of Investments

All available-for-sale debt securities are periodically reviewed for impairment. An investment is considered to be impaired when its fair value is less than its amortized cost basis and it is more likely than not that we will be required to sell the impaired security before recovery of its amortized cost basis. Factors considered in determining whether a loss is temporary include the magnitude of the decline in market value, the length of time the market value has been below cost (or adjusted cost), credit quality, and our ability and intent to hold the securities for a period of time sufficient to allow for any anticipated recovery in market value.

We also invest in equity instruments of privately held companies in China for business and strategic purposes. Investments in our unconsolidated joint venture companies are classified as other assets and accounted for under either the equity or fair value method, depending on whether we have the ability to exercise significant influence over their operations or financial decisions. We monitor our investments for impairment and record reductions in carrying value when events or changes in circumstances indicate that the carrying value may not be recoverable. Determination of impairment is highly

subjective and is based on a number of factors, including an assessment of the strength of each company’s management, the length of time and extent to which the fair value has been less than our cost basis, the financial condition and near-term prospects of the subsidiary, fundamental changes to the business prospects of the Company, share prices of subsequent offerings, and our intent and ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in our carrying value. We estimate fair value of our fair value method investments considering available information such as pricing in recent rounds of financing, current cash positions, earnings (loss) and cash flow forecasts, recent operational performance, and any other readily available market data.

For the year ended December 31, 2023, one of our PRC joint ventures assessed one of its equity investments was fully impaired. For the year ended December 31, 2023, we divested our equity investment in a PRC joint venture. The impairment and divestiture resulted in a total of $1.9 million in impairment charges in our financial results. There were no impairment charges during the year ended December 31, 2022.
Segment Reporting

Segment Reporting

We operate in one segment for the design, development, manufacture and distribution of high-performance compound and single element semiconductor substrates and sale of raw materials integral to these substrates. Our chief operating decision-maker has been identified as our Chief Executive Officer, who reviews operating results to make decisions about allocating resources and assessing our performance for the Company. We discuss revenue and capacity for both AXT and our joint ventures collectively, when determining capacity constraints and need for raw materials in our business, and consider their capacity when determining our strategic and product marketing and advertising strategies. While we consolidate our majority-owned or significantly controlled joint ventures, we do not allocate any portion of overhead, interest and other income, interest expense or taxes to them. We therefore have determined that our joint venture operations do not constitute an operating segment. Since we operate in one segment, all financial segment and product line information can be found in the consolidated financial statements.

Stock-Based Compensation

Stock-Based Compensation

We have employee stock option plans, which are described more fully in Note 10-“Employee Benefit Plans and Stock-based Compensation”. We account for stock-based compensation in accordance with the provisions of ASC Topic 718, Compensation-Stock Compensation (“ASC 718”). We utilize the Black-Scholes option pricing model to estimate the grant date fair value of stock options, which requires the input of highly subjective assumptions, including estimating stock price volatility and expected term. Stock-based compensation cost is measured at each grant date, based on the fair value of the award, and is recognized as expense and as an increase in additional paid-in capital over the requisite service period of the award.

Research and Development

Research and Development

Research and development costs consist primarily of salaries, including stock-based compensation expense and related personnel costs, depreciation, materials and product testing which are expensed as incurred. Tangible assets acquired for research and development purposes are capitalized if they have alternative future use.

​
Advertising Costs

Advertising Costs

Advertising costs, included in selling, general and administrative expenses, are expensed as incurred. Advertising costs for the years ended December 31, 2023, 2022 and 2021 were insignificant.
Income Taxes

Income Taxes

We account for income taxes in accordance with ASC Topic 740, Income Taxes (“ASC 740”), which requires that deferred tax assets and liabilities be recognized using enacted tax rates for the effect of temporary differences between the book and tax bases of recorded assets and liabilities. ASC 740 also requires that deferred tax assets be reduced by a valuation allowance if it is more likely than not that a portion of the deferred tax asset will not be realized. The impact of ASC 740 is more fully described in Note 12.
Comprehensive Income (loss)

Comprehensive Income (loss)

The components of other comprehensive income (loss) include unrealized gains and losses on marketable securities and foreign currency translation adjustments. Comprehensive income (loss) is presented in the consolidated statements of comprehensive income (loss). The balance of accumulated other comprehensive income (loss) is as follows (in thousands):

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

2023

​

2022

Accumulated other comprehensive loss:

​

​

​

​

​

​

Unrealized loss on investments, net

​

$

(20)

​

$

(303)

Cumulative translation adjustment

​

 

(6,530)

​

​

(3,042)

​

​

 

(6,550)

​

​

(3,345)

Less: Cumulative translation adjustment attributable to noncontrolling interests and redeemable noncontrolling interests

​

​

(551)

​

​

(227)

Accumulated other comprehensive loss attributable to AXT, Inc.

​

$

(5,999)

​

$

(3,118)
Net Income (Loss) Per Share

Net Income (Loss) Per Share

Basic net income (loss) per share is computed using the weighted-average number of common shares outstanding during the periods less shares of common stock subject to repurchase and non-vested stock awards. Diluted net income (loss) per share is computed using the weighted-average number of common shares outstanding and potentially dilutive common shares outstanding during the periods. The dilutive effect of outstanding stock options and restricted stock awards is reflected in diluted earnings per share by application of the treasury stock method. Potentially dilutive common shares consist of common shares issuable upon the exercise of stock options and vesting of restricted stock awards. Potentially dilutive common shares are excluded from the computation of weighted-average number of common shares outstanding in net loss years, as their effect would be anti-dilutive to the computation.
Recent Accounting Pronouncements

Recent Accounting Pronouncements

In March 2022, the Financial Accounting Standards Board (“FASB”) pronouncement Accounting Standards Update (“ASU”) 2022-02, Financial Instruments-Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures was issued as an amendment to ASU 2016-13, Financial Instruments-Credit Losses. ASU 2022-02 aims to modify disclosure requirements for certain loan refinancings and restructurings by creditors. The amendment also require that an entity disclose current-period gross write offs by year of origination for financing receivables and net investments in leases within the scope of Subtopic 326-20, Financial Instruments—Credit Losses—Measured at Amortized Cost. The guidance is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Adoption of the new standard had an immaterial effect on our consolidated financial statements.

In September 2022, FASB issued ASU 2022-04, Liabilities—Supplier Finance Programs (Subtopic 405-50): Disclosure of Supplier Finance Program Obligations, to enhance the transparency about the use of supplier finance programs for investors. The amendments in this Update require that a buyer in a supplier finance program disclose sufficient information about the program to allow a user of financial statements to understand the program’s nature, activity during the period, changes from period to period, and potential magnitude. The guidance is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Adoption of the new standard had an immaterial effect on our consolidated financial statements.

In November 2023, FASB released ASU 2023-07— Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, aiming to enhance the transparency and relevance of segment information provided in financial statements. The amendments in this Update require that a public entity disclose significant segment expenses, profit or loss and assets, etc. for each reportable segment, on an annual and interim basis. The Update is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Adoption of the new standard will have an immaterial effect on our consolidated financial statements.

In December 2023, FASB issued ASU 2023-09— Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to help investors better understand an entity’s exposure to potential changes in jurisdictional tax legislation and the ensuing risks and opportunities. Furthermore, the Update improves to assess income tax information that affects cash flow forecasts and capital allocation decisions. The Update is effective for public business entities for annual periods beginning after December 15, 2024, on a prospective basis. Adoption of the new standard will have an immaterial effect on our consolidated financial statements.
v3.24.0.1
The Company and Summary of Significant Accounting Policies (Tables)
 12 Months Ended
Dec. 31, 2023
The Company and Summary of Significant Accounting Policies  
Schedule of amounts recorded in accrued liabilities

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​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31,

​

​

​

2023

​

2022

​

Contract liabilities

​

$

305

​

$

338

​

During the three and twelve months ended December 31, 2023, the Company recognized $9,000 and $287,000, respectively, of revenue that was included in the contract balances as of December 31, 2022. During the three and twelve months ended December 31, 2022, the Company recognized $22,000 and $760,000 of revenue that was included in the contract balances as of December 31, 2021.

​

​

​

​

​

​

​
Schedule of accumulated other comprehensive income (loss)

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

2023

​

2022

Accumulated other comprehensive loss:

​

​

​

​

​

​

Unrealized loss on investments, net

​

$

(20)

​

$

(303)

Cumulative translation adjustment

​

 

(6,530)

​

​

(3,042)

​

​

 

(6,550)

​

​

(3,345)

Less: Cumulative translation adjustment attributable to noncontrolling interests and redeemable noncontrolling interests

​

​

(551)

​

​

(227)

Accumulated other comprehensive loss attributable to AXT, Inc.

​

$

(5,999)

​

$

(3,118)
v3.24.0.1
Cash, Cash Equivalents and Investments (Tables)
 12 Months Ended
Dec. 31, 2023
Cash, Cash Equivalents and Investments  
Cash, cash equivalents and investments

Our cash and cash equivalents consist of cash and instruments with original maturities of less than three months. Our investments consist of instruments with original maturities of more than three months. As of December 31, 2023 and 2022, our cash, cash equivalents and debt investments are classified as follows (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

December 31, 2023

​

December 31, 2022

 

​

    

​

​

    

Gross

    

Gross

    

​

​

    

​

​

    

Gross

    

Gross

    

​

​

 

​

​

Amortized

​

Unrealized

​

Unrealized

​

Fair

​

Amortized

​

Unrealized

​

Unrealized

​

Fair

 

​

    

Cost

    

Gain

    

(Loss)

    

Value

    

Cost

    

Gain

    

(Loss)

    

Value

 

Classified as:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Cash and restricted cash

​

$

50,114

​

$

—

​

$

—

​

$

50,114

​

$

41,348

​

$

—

​

$

—

​

$

41,348

​

Cash equivalents:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit 1

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

​

—

​

Total cash, restricted cash and cash equivalents

​

 

50,114

​

 

—

​

 

—

​

 

50,114

​

 

41,348

​

 

—

​

 

—

​

 

41,348

​

Investments (available-for-sale):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit 2

​

 

2,160

​

 

—

​

​

(20)

​

 

2,140

​

 

6,440

​

 

—

​

​

(175)

​

 

6,265

​

Corporate bonds

​

 

—

​

 

—

​

 

—

​

 

—

​

 

5,320

​

 

—

​

 

(128)

​

 

5,192

​

Total investments

​

 

2,160

​

 

—

​

 

(20)

​

 

2,140

​

 

11,760

​

 

—

​

 

(303)

​

 

11,457

​

Total cash, restricted cash, cash equivalents and investments

​

$

52,274

​

$

—

​

$

(20)

​

$

52,254

​

$

53,108

​

$

—

​

$

(303)

​

$

52,805

​

Contractual maturities on investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Due within 1 year 3

​

$

2,160

​

​

​

​

​

​

​

$

2,140

​

$

9,600

​

​

​

​

​

​

​

$

9,339

​

Due after 1 through 5 years 4

​

 

—

​

​

​

​

​

​

​

 

—

​

 

2,160

​

​

​

​

​

​

​

 

2,118

​

​

​

$

2,160

​

​

​

​

​

​

​

$

2,140

​

$

11,760

​

​

​

​

​

​

​

$

11,457

​

1.Certificate of deposit with original maturities of less than three months.
2.Certificate of deposit with original maturities of more than three months.
3.Classified as “Short-term investments” in our consolidated balance sheets.
4.Classified as “Long-term investments” in our consolidated balance sheets.

​
Fair value and gross unrealized losses related to available-for-sale securities

The following table summarizes the fair value and gross unrealized losses related to available-for-sale debt securities, aggregated by investment category and length of time that individual debt securities have been in a continuous unrealized loss position as of December 31, 2023 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

In Loss Position

​

In Loss Position

​

Total In

 

​

​

< 12 months

​

> 12 months

​

Loss Position

 

​

​

​

​

​

Gross

​

​

​

​

Gross

​

​

​

​

Gross

 

​

​

Fair

​

Unrealized

​

Fair

​

Unrealized

​

Fair

​

Unrealized

 

As of December 31, 2023

    

Value

    

(Losses)

    

Value

    

(Losses)

    

Value

    

(Losses)

 

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

—

​

$

—

​

$

2,140

​

$

(20)

​

$

2,140

​

$

(20)

​

Total in loss position

​

$

—

​

$

—

​

$

2,140

​

$

(20)

​

$

2,140

​

$

(20)

​

​

The following table summarizes the fair value and gross unrealized losses related to available-for-sale debt securities, aggregated by investment category and length of time that individual debt securities have been in a continuous unrealized loss position as of December 31, 2022 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

In Loss Position

​

In Loss Position

​

Total In

 

​

​

< 12 months

​

> 12 months

​

Loss Position

 

​

    

    

​

    

Gross

    

    

​

    

Gross

    

    

​

    

Gross

 

​

​

Fair

​

Unrealized

​

Fair

​

Unrealized

​

Fair

​

Unrealized

 

As of December 31, 2022

​

Value

​

(Loss)

​

Value

​

(Loss)

​

Value

​

(Loss)

 

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

2,118

​

$

(42)

​

$

4,146

​

$

(133)

​

$

6,264

​

$

(175)

​

Corporate bonds

​

 

—

​

 

—

​

 

4,842

​

 

(128)

​

 

4,842

​

​

(128)

​

Total in loss position

​

$

2,118

​

$

(42)

​

$

8,988

​

$

(261)

​

$

11,106

​

$

(303)

​
Summary of financial assets and liabilities measured at fair value on a recurring basis

The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis in accordance with ASC 820 as of December 31, 2023 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

    

​

​

    

Quoted Prices in

    

​

​

​

Significant

 

​

​

​

​

​

Active Markets of

​

Significant Other

​

Unobservable

 

​

​

Balance as of

​

Identical Assets

​

Observable Inputs

​

Inputs

 

​

    

December 31, 2023

    

(Level 1)

    

(Level 2)

    

(Level 3)

 

Assets:

​

​

​

​

​

​

​

​

​

​

​

​

​

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

2,140

​

$

—

​

$

2,140

​

$

—

​

Corporate bonds

​

 

—

​

 

—

​

 

—

​

 

—

​

Total

​

$

2,140

​

$

—

​

$

2,140

​

$

—

​

​

The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis in accordance with ASC 820 as of December 31, 2022 (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

    

​

​

    

Quoted Prices in

    

​

​

​

Significant

 

​

​

​

​

​

Active Markets of

​

Significant Other

​

Unobservable

 

​

​

Balance as of

​

Identical Assets

​

Observable Inputs

​

Inputs

 

​

    

December 31, 2022

    

(Level 1)

    

(Level 2)

    

(Level 3)

 

Assets:

​

​

​

​

​

​

​

​

​

​

​

​

​

Investments:

​

​

​

​

​

​

​

​

​

​

​

​

​

Certificates of deposit

​

$

6,265

​

$

—

​

$

6,265

​

$

—

​

Corporate bonds

​

 

5,192

​

 

—

​

 

5,192

​

 

—

​

Total

​

$

11,457

​

$

—

​

$

11,457

​

$

—

​
v3.24.0.1
Inventories (Tables)
 12 Months Ended
Dec. 31, 2023
Inventories  
Components of inventories

The components of inventory are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

​

    

2023

    

2022

 

Inventories:

​

​

​

​

​

​

​

Raw materials

​

$

32,910

​

$

46,476

​

Work in process

​

 

50,008

​

 

39,956

​

Finished goods

​

 

3,585

​

 

3,197

​

​

​

$

86,503

​

$

89,629

​

​
v3.24.0.1
Property, Plant and Equipment, Net (Tables)
 12 Months Ended
Dec. 31, 2023
Property, Plant and Equipment, Net  
Schedule of components of property, plant and equipment

The components of our property, plant and equipment are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

​

​

2023

​

2022

​

Property, plant and equipment:

​

​

​

​

​

​

​

Machinery and equipment, at cost

​

$

65,918

​

$

62,797

​

Less: accumulated depreciation and amortization

​

​

(42,112)

​

​

(38,477)

​

Building, at cost

​

​

125,786

​

​

118,550

​

Less: accumulated depreciation and amortization

​

​

(23,339)

​

​

(20,403)

​

Leasehold improvements, at cost

​

 

7,596

​

 

7,430

​

Less: accumulated depreciation and amortization

​

​

(5,984)

​

​

(5,559)

​

Construction in progress

​

 

38,483

​

 

36,679

​

​

​

$

166,348

​

$

161,017

​
v3.24.0.1
Investments in Privately-held Raw Material Companies (Tables)
 12 Months Ended
Dec. 31, 2023
Investments in Privately-Held Raw Material Companies  
Summary of investments

The investments are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Investment Balance as of

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

Accounting

​

Ownership

*

Company

    

2023

    

2022

    

Method

    

Percentage

​

Nanjing JinMei Gallium Co., Ltd.

​

$

592

​

$

592

 

Consolidated

 

** 85.5

%

ChaoYang JinMei Gallium Co., Ltd.

​

​

1,820

​

​

1,820

​

Consolidated

​

** 85.5

%

Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd.

​

 

1,346

​

 

1,346

 

Consolidated

 

** 85.5

%

ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.

​

​

3,122

​

​

1,000

​

Consolidated

​

**** 75.0

%

ChaoYang XinMei High Purity Semiconductor Materials Co., Ltd.

​

​

7,331

​

​

7,331

​

Consolidated

 

*** 58.5

%

​

​

$

14,211

​

$

12,089

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Beijing JiYa Semiconductor Material Co., Ltd.

​

$

3,806

​

​

6,381

​

Equity

​

39

%

Xiaoyi XingAn Gallium Co., Ltd.

​

​

5,516

​

​

5,094

​

Equity

​

** 25

%

ChaoYang KaiMei Quartz Co., Ltd.

​

​

3,154

​

​

827

​

Equity

​

***** 40

%

Emeishan Jia Mei High Purity Metals Co., Ltd.

​

 

N/A

​

 

418

 

Equity

 

****** 25

%

​

​

$

12,476

​

$

12,720

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Emeishan Jia Mei High Purity Metals Co., Ltd.

​

 

551

​

 

N/A

 

Fair value

 

****** 10

%

​

​

$

551

​

$

—

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Donghai County Dongfang High Purity Electronic Materials Co., Ltd.

​

 

—

​

 

1,887

 

N/A

 

******* 0

%

​

​

$

—

​

$

1,887

​

​

​

​

​
Summarized balance sheet information

These minority investment entities that are not consolidated, but rather are accounted for under the equity method, had the following summarized balance sheet information (in thousands) as of December 31, 2023 and 2022, respectively: (The 2023 balance sheet information excludes Jia Mei.)

​

​

​

​

​

​

​

​

​

​

As of December 31, 

 

​

    

2023

​

2022

 

Current assets

​

$

31,636

    

$

43,091

​

Noncurrent assets

​

 

19,751

​

 

12,520

​

Current liabilities

​

 

7,367

​

 

10,552

​

Noncurrent liabilities

​

 

—

​

 

—

​
Schedule of gain (loss) on sale and re measurement of equity method investments

​

​

​

​

​

​

​

Amount

​

    

(in thousands)

Fair value of the consideration received

​

$

779

Foreign income tax withholding

​

​

48

Carrying value of 15% of Emeishan Jia Mei High Purity Metals Co., Ltd.

​

​

(252)

Gain recognized on sale of 15% of Emeishan Jia Mei High Purity Metals Co., Ltd.

​

$

575

​

​

​

​

​

​

​

​

​

​

Amount

​

​

(in thousands)

Fair value of the retained investment in Emeishan Jia Mei High Purity Metals Co., Ltd.

​

$

551

Carrying value of retained noncontrolling investment (10%)

​

​

(168)

Gain on retained noncontrolling investment due to remeasurement (10%)

​

$

383

​

​

​

​

​

​

​

Amount

​

    

(in thousands)

Fair value of the consideration received

​

$

585

Carrying value of 46% of Donghai County Dongfang High Purity Electronic Materials Co., Ltd.

​

​

(1,710)

Loss recognized on sale of 46% of Donghai County Dongfang High Purity Electronic Materials Co., Ltd.

​

$

(1,125)
Summarized income information

AXT’s minority investment entities are not consolidated and are accounted for under the equity method. The equity entities had the following summarized income information (in thousands) for the years ended December 31, 2023, 2022 and 2021, respectively: (The 2023 income information includes results of Jia Mei for Q1 and Q2.)

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Our share for the

 

​

​

​

Year Ended

​

Year Ended

 

​

​

​

December 31, 

​

December 31, 

 

​

    

2023

    

2022

​

2021

    

2023

    

2022

    

2021

 

Net revenue

​

$

32,544

​

$

48,139

​

$

35,939

​

$

10,033

​

$

15,031

​

$

11,424

​

Gross profit

​

 

11,698

​

 

27,000

​

 

17,465

​

 

3,365

​

 

8,229

​

 

5,482

​

Operating income

​

 

10,115

​

 

24,987

​

 

14,293

​

 

2,724

​

 

7,532

​

 

4,495

​

Net income

​

​

8,681

​

​

19,104

​

​

12,560

​

​

1,884

​

​

5,957

​

​

4,409

​
v3.24.0.1
Balance Sheets Details (Tables)
 12 Months Ended
Dec. 31, 2023
Balance Sheets Details  
Schedule of components of other assets

The components of other assets are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

 

2023

    

2022

​

Equity method investments

​

​

$

12,476

​

$

14,607

​

Value added tax receivable, long term

​

​

​

1,291

​

​

1,632

​

Other intangible assets

​

​

​

1,821

​

​

1,926

​

Deferred tax assets

​

​

​

1,683

​

​

2,236

​

Other assets

​

​

​

1,627

​

​

1,230

​

​

​

​

$

18,898

​

$

21,631

​
Schedule of components of accrued liabilities

The components of accrued liabilities are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

​

 

2023

    

2022

 

Payable in connection with construction in progress

​

$

7,249

​

$

4,135

​

Accrued compensation and related charges

​

​

3,707

​

​

4,774

​

Preferred stock dividends payable

​

​

2,901

​

​

2,901

​

Accrued professional services

​

​

868

​

​

930

​

Accrued product warranty

​

​

703

​

​

669

​

Other tax payable

​

​

493

​

​

867

​

Current portion of operating lease liabilities

​

​

458

​

​

485

​

Advances from customers

​

​

305

​

​

338

​

Other personnel-related costs

​

​

286

​

​

291

​

Accrual for sales returns

​

​

39

​

​

112

​

Accrued income taxes

​

​

—

​

​

729

​

Other accrued liabilities

​

​

2,010

​

​

1,933

​

​

​

$

19,019

​

$

18,164

​

​

​

​

​

​

​

​

​

​
v3.24.0.1
Bank Loans and Line of Credit (Tables)
 12 Months Ended
Dec. 31, 2023
Bank Loans and Line of Credit  
Schedule of bank loans and line of credit

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Loan

Interest

​

​

​

​

​

December 31, 

​

December 31, 

Subsidiary

Bank

​

Detail

Rate

​

Start Date

​

Due Date

​

2022

​

2023

Tongmei

Bank of China (1)

$

2,108

2.7

%  

September-22

​

March-23

$

2,175

$

-

​

​

​

3,935

4.6

%  

January-22

​

January-23

​

4,059

​

-

​

​

​

1,405

4.2

%  

April-22

​

April-23

​

1,450

​

-

​

Bank of China (5)

​

1,848

3.5

%  

January-23

​

January-24

​

-

​

1,795

​

​

​

2,184

2.8

%  

March-23

​

March-24

​

-

​

2,118

​

​

​

376

2.7

%  

September-23

​

September-24

​

-

​

386

​

​

​

876

3.5

%  

November-23

​

November-24

​

-

​

876

​

​

​

1,003

3.5

%  

November-23

​

November-24

​

-

​

1,003

​

Bank of China (3)

​

2,911

3.5

%  

January-23

​

January-24

​

-

​

2,825

​

Bank of Communications (2)

​

1,405

3.3

%  

January-22

​

January-23

​

1,450

​

-

​

​

​

1,405

3.3

%  

January-22

​

January-23

​

1,450

​

-

​

Bank of Communications (5)

​

1,450

3.3

%  

December-22

​

December-23

​

1,450

​

-

​

​

​

1,455

3.3

%  

January-23

​

January-24

​

-

​

1,414

​

​

​

1,380

3.8

%  

May-23

​

May-24

​

-

​

1,414

​

​

​

1,373

3.8

%  

July-23

​

May-24

​

-

​

1,414

​

China Merchants Bank (5)

​

4,367

3.7

%  

January-23

​

January-24

​

-

​

4,235

​

Bank of Beijing (4)

​

3,192

4.2

%  

May-22

​

May-23

​

3,292

​

-

​

​

​

2,290

4.2

%  

January-23

​

January-24

​

-

​

2,220

​

​

​

3,541

3.2

%  

June-23

​

May-24

​

-

​

3,626

​

​

​

1,380

3.2

%  

June-23

​

February-24

​

-

​

1,414

​

​

​

1,414

3.0

%  

December-23

​

December-24

​

-

​

1,414

​

Industrial Bank (5)

​

5,621

4.4

%  

June-22

​

June-23

​

5,798

​

-

​

​

​

2,811

4.4

%  

September-22

​

September-23

​

2,900

​

-

​

​

​

2,757

4.3

%  

June-23

​

June-24

​

-

​

2,825

​

​

​

2,744

4.3

%  

July-23

​

July-24

​

-

​

2,825

​

​

​

2,744

4.3

%  

September-23

​

September-24

​

-

​

2,825

​

NingBo Bank (5)

​

1,405

4.8

%  

June-22

​

June-23

​

1,450

​

-

​

​

​

1,405

4.8

%  

August-22

​

August-23

​

1,450

​

-

​

​

​

1,405

4.8

%  

September-22

​

September-23

​

1,450

​

-

​

​

​

1,406

4.5

%  

November-22

​

November-23

​

1,450

​

-

​

​

​

2,900

4.5

%  

December-22

​

December-23

​

2,900

​

-

​

​

​

2,744

4.2

%  

August-23

​

September-24

​

-

​

2,820

​

​

​

1,271

4.3

%  

November-23

​

November-24

​

-

​

1,271

​

​

​

2,825

4.3

%  

December-23

​

December-24

​

-

​

2,825

​

Industrial and Commercial Bank of China (5)

​

5,621

3.2

%  

September-22

​

July-23

​

5,800

​

-

​

​

​

2,744

3.3

%  

September-23

​

September-24

​

-

​

2,825

​

NanJing Bank (5)

​

2,811

4.3

%  

September-22

​

September-23

​

2,899

​

-

​

​

​

1,265

4.3

%  

November-22

​

November-23

​

1,305

​

-

​

​

​

2,752

3.8

%  

October-23

​

October-24

​

-

​

2,752

BoYu

Industrial and Commercial Bank of China (6)

​

1,450

2.8

%  

December-22

​

December-23

​

1,450

​

-

​

​

​

1,414

2.7

%  

December-23

​

December-24

​

-

​

1,414

​

Bank of China (5)

​

1,204

2.4

%  

January-23

​

January-24

​

-

​

849

​

NingBo Bank (5)

​

703

4.8

%  

September-22

​

March-23

​

725

​

-

​

​

​

1,406

3.6

%  

November-22

​

May-23

​

1,450

​

-

​

​

​

725

4.8

%  

December-22

​

June-23

​

725

​

-

​

​

​

1,414

3.3

%  

November-23

​

May-24

​

-

​

1,414

​

Industrial Bank (5)

​

688

3.6

%  

September-23

​

September-24

​

-

​

708

​

Bank of Communications (5)

​

1,414

3.0

%  

November-23

​

May-24

​

-

​

1,414

​

Loan Balance

​

​

​

​

​

​

​

$

47,078

$

52,921

Collateral for the above bank loans and line of credit

(1)Baoding Tongmei’s land use rights and all of its buildings located at its facility in Dingxing, China.
(2)ChaoYang Tongmei’s land use rights and all of its buildings located at its facility in Kazuo, China.
(3)ChaoYang LiMei time deposit.
(4)AXT time deposit.
(5)Not collateralized.
(6)BoYu’s land use rights and its building located at its facility in Tianjin, China. In addition, the December 2023 loan attracts a guarantee fee amounting to 0.7% of the loan amount.
v3.24.0.1
Stockholders' Equity and Stock Repurchase Program (Tables)
 12 Months Ended
Dec. 31, 2023
Stockholders' Equity and Stock Repurchase Program  
Schedule of changes in ownership interest in consolidated subsidiaries

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

    

2023

​

2022

Net income (loss) attributable to AXT, Inc.

​

$

(17,881)

    

$

15,811

Decrease in additional paid-in capital for:

​

 

​

​

 

​

Investment in subsidiary with noncontrolling interest

​

 

(308)

​

 

(937)

Change from net income (loss) attributable to AXT, Inc., net of transfers to noncontrolling interests

​

$

(18,189)

​

$

14,874
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation (Tables)
 12 Months Ended
Dec. 31, 2023
Employee Benefit Plans and Stock-based Compensation  
Summary of compensation costs related to stock-based awards

​

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

​

December 31, 

​

​

 

2023

    

2022

​

2021

 

Cost of revenue

​

$

414

​

$

379

​

$

368

​

Selling, general and administrative

​

 

2,502

​

 

2,947

​

 

3,514

​

Research and development

​

 

624

​

 

680

​

 

637

​

Net effect on net income (loss)

​

$

3,540

​

$

4,006

​

$

4,519

​

Shares used in computing basic net income (loss) per share

​

 

42,643

​

 

42,104

​

 

41,367

​

Shares used in computing diluted net income (loss) per share

​

 

42,643

​

 

42,715

​

 

42,720

​

Effect on basic net income (loss) per share

​

$

0.08

​

$

0.10

​

$

0.11

​

Effect on diluted net income (loss) per share

​

$

0.08

​

$

0.09

​

$

0.11

​

​
Summary of stock option activity

The following table summarizes the stock option transactions for each of the years ended December 31, 2021, 2022 and 2023 (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Weighted-

​

​

​

​

​

    

​

    

​

​

    

average

    

​

​

 

​

​

​

​

Weighted-

​

Remaining

​

​

​

 

​

​

Number of

​

average

​

Contractual

​

Aggregate

 

​

​

Options

​

Exercise

​

Life

​

Intrinsic

 

Stock Options

    

Outstanding

    

Price

    

(in years)

    

Value

 

Balance as of January 1, 2021

 

1,885

​

$

4.42

 

6.17

​

$

9,713

​

Granted

 

—

​

 

—

​

​

​

​

​

​

Exercised

 

(507)

​

 

3.30

​

​

​

​

​

​

Canceled and expired

 

—

​

 

—

​

​

​

​

​

​

Balance as of December 31, 2021

 

1,378

​

$

4.83

 

5.60

​

$

5,573

​

Granted

 

—

​

 

—

​

​

​

​

​

​

Exercised

 

(172)

​

 

3.02

​

​

​

​

​

​

Canceled and expired

 

—

​

 

—

​

​

​

​

​

​

Balance as of December 31, 2022

​

1,206

​

$

5.09

 

5.08

​

$

630

​

Granted

 

—

​

 

—

​

​

​

​

​

​

Exercised

 

(4)

​

​

2.30

​

​

​

​

​

​

Canceled and expired

 

(4)

​

​

4.12

​

​

​

​

​

​

Balance as of December 31, 2023

 

1,198

​

$

5.10

 

4.09

​

$

14

​

Options vested as of December 31, 2023 and unvested options expected to vest, net of forfeitures

 

1,198

​

$

5.10

 

4.09

​

$

14

​

Options exercisable as of December 31, 2023

 

1,198

​

$

5.10

 

4.09

​

$

14

​

​
Summary of options outstanding and exercisable by exercise price ranges

The options outstanding and exercisable as of December 31, 2023 were in the following exercise price ranges (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Options Vested and

 

​

​

​

​

​

​

Options Outstanding as of

​

Exercisable as of

 

​

​

​

​

​

​

December 31, 2023

​

December 31, 2023

 

​

​

​

​

​

​

​

    

​

​

    

Weighted‑average

    

​

    

​

​

 

Range of

​

​

​

Weighted‑average

    

Remaining

​

​

​

Weighted‑Average

 

Exercise Price

​

Shares

​

Exercise Price

    

Contractual Life

​

Shares

​

Exercise Price

 

$

2.14

-

$

2.14

​

8

​

$

2.14

 

0.33

 

8

​

$

2.14

​

$

2.18

-

$

2.18

​

54

​

$

2.18

 

1.84

 

54

​

$

2.18

​

$

2.47

-

$

2.47

​

15

​

$

2.47

 

0.84

 

15

​

$

2.47

​

$

2.56

-

$

2.56

​

10

​

$

2.56

 

2.01

 

10

​

$

2.56

​

$

3.06

-

$

3.06

​

330

​

$

3.06

 

5.85

 

330

​

$

3.06

​

$

5.21

-

$

5.21

​

352

​

$

5.21

 

2.82

 

352

​

$

5.21

​

$

5.77

-

$

5.77

​

245

​

$

5.77

 

4.85

 

245

​

$

5.77

​

$

7.95

-

$

7.95

​

60

​

$

7.95

 

3.08

 

60

​

$

7.95

​

$

9.50

-

$

9.50

​

124

​

$

9.50

 

3.82

 

124

​

$

9.50

​

​

​

​

​

​

​

1,198

​

$

5.10

 

4.09

 

1,198

​

$

5.10

​

​
Summary of restricted stock awards activity

A summary of activity related to restricted stock awards for the years ended December 31, 2021, 2022 and 2023 is presented below (in thousands, except per share data):

​

​

​

​

​

​

​

​

    

​

    

Weighted-Average

 

​

​

​

​

Grant Date

 

Stock Awards

    

Shares

    

Share Value

 

Non-vested as of January 1, 2021

 

1,022

​

$

5.27

​

Granted

 

274

​

$

9.07

​

Vested

 

(407)

​

$

5.70

​

Forfeited

 

(14)

​

$

5.38

​

Non-vested as of December 31, 2021

 

875

​

$

6.26

​

Granted

 

513

​

$

4.67

​

Vested

 

(387)

​

$

6.01

​

Forfeited

 

(17)

​

$

5.34

​

Non-vested as of December 31, 2022

​

984

​

$

5.55

​

Granted

 

692

​

$

2.20

​

Vested

 

(446)

​

$

5.25

​

Forfeited

​

(10)

​

$

6.37

​

Non-vested as of December 31, 2023

 

1,220

​

$

3.75

​
Summary of unvested at-risk performance shares

A summary of the status of our unvested at-risk, performance shares as of December 31, 2023 is presented below (in thousands, except per share data):

​

​

​

​

​

​

​

    

​

    

Weighted-Average

​

​

​

​

Grant Date

Stock Awards

    

Shares

    

Share Value

Non-vested as of January 1, 2022

 

152

*

$

15.37

Granted

 

74

​

$

7.83

Vested

 

(76)

​

$

15.37

Forfeited

 

(74)

​

$

7.83

Non-vested as of December 31, 2022

​

76

​

$

15.37

Granted

 

13

​

$

3.71

Vested

 

(38)

​

$

15.37

Forfeited

​

(13)

​

$

3.71

Non-vested as of December 31, 2023

 

38

​

$

15.37

*The number of share presented is based on achieving 150% of the targeted financial performance metric as defined in the at-risk, performance shares agreement.

Summary of common stock reserved for future issuance

The following number of shares of common stock were reserved and available for future issuance as of December 31, 2023 (in thousands, except per share data):

​

​

​

​

Options outstanding

    

1,198

​

Restricted stock awards outstanding

 

1,257

​

Stock available for future grant: 2015 Equity Incentive Plan

 

1,743

​

Total

 

4,198

​
v3.24.0.1
Guarantees (Tables)
 12 Months Ended
Dec. 31, 2023
Guarantees  
Product warranty accrued liability

​

​

​

​

​

​

​

​

​

​

Year Ended

 

​

​

December 31, 

 

​

    

2023

    

2022

 

Beginning accrued product warranty

​

$

669

​

$

743

​

Accruals for warranties issued

​

 

794

​

 

1,024

​

Adjustments related to pre-existing warranties including expirations and changes in estimates

​

 

(159)

​

 

(286)

​

Cost of warranty repair

​

 

(601)

​

 

(812)

​

Ending accrued product warranty

​

$

703

​

$

669

​

​
v3.24.0.1
Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2023
Income Taxes  
Components of the provision (benefits) for income taxes

​

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended December 31, 

 

​

    

2023

    

2022

    

2021

 

Current:

​

​

​

​

​

​

​

​

​

​

Federal

​

$

(317)

​

$

848

​

$

223

​

State

​

 

41

​

 

34

​

 

91

​

Foreign

​

 

(62)

​

 

918

​

 

3,119

​

Total current

​

 

(338)

​

 

1,800

​

 

3,433

​

Deferred:

​

​

​

​

​

​

​

​

​

​

Federal

​

 

(9)

​

 

(591)

​

 

(188)

​

State

​

​

(7)

​

​

(4)

​

​

(1)

​

Foreign

​

 

514

​

 

980

​

 

(2,151)

​

Total deferred

​

 

498

​

 

385

​

 

(2,340)

​

Total provision for income taxes

​

$

160

​

$

2,185

​

$

1,093

​
Reconciliation of the effective income tax rates and the U.S. statutory federal income tax rate

​

​

​

​

​

​

​

​

​

​

​

Year Ended December 31, 

 

​

    

2023

    

2022

    

2021

 

Statutory federal income tax rate

 

21.0

%  

21.0

%  

21.0

%  

State income taxes, net of federal tax benefits

 

(0.6)

​

0.1

​

0.4

​

Valuation allowance

 

(25.7)

​

(19.3)

​

(25.4)

​

Stock-based compensation

 

(1.7)

​

0.7

​

(3.2)

​

Foreign tax rate differential

​

6.1

​

(2.6)

​

(8.6)

​

Foreign tax incentives

​

0.1

​

(3.5)

​

(3.2)

​

Foreign income inclusion

​

—

​

18.9

​

10.4

​

Gain from sale of IP

​

—

​

—

​

16.9

​

Tax effect in equity method loss or gain from unconsolidated affiliates

​

0.4

​

(3.0)

​

(2.6)

​

Other

​

(0.4)

​

(1.8)

​

0.5

​

Effective tax rate

 

(0.8)

%  

10.5

%  

6.2

%  
Deferred tax assets and liabilities

Deferred tax assets and liabilities are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

As of December 31, 

 

​

    

2023

    

2022

 

Deferred tax assets:

​

​

​

​

​

​

​

Net operating loss carryforwards

​

$

14,362

​

$

9,571

​

Accruals, reserves and other

​

 

4,349

​

 

4,053

​

Credit carryforwards

​

 

325

​

 

206

​

Operating lease liability

​

 

206

​

 

60

​

Gross deferred tax assets

​

​

19,242

​

​

13,890

​

Valuation allowance

​

 

(17,462)

​

 

(11,885)

​

Total deferred tax assets

​

 

1,780

​

 

2,005

​

Deferred tax liabilities:

​

 

​

​

 

​

​

Operating lease right-of-use assets

​

 

(323)

​

 

(50)

​

Total net deferred tax assets (included in other assets)

​

$

1,457

​

$

1,955

​

​

As of December 31, 2023 we have federal net operating loss (“NOL”) carryforwards of approximately $40.2 million, which will begin to expire in 2025. We have California net operating loss carryforwards of approximately $115,000 as of December 31, 2023.
v3.24.0.1
Net Income (Loss) Per Share (Tables)
 12 Months Ended
Dec. 31, 2023
Net Income (Loss) per Share  
Reconciliation of numerators and denominators of basic and diluted net income per share

A reconciliation of the numerators and denominators of the basic and diluted net income per share calculations is as follows (in thousands, except per share data):

​

​

​

​

​

​

​

​

​

​

​

​

​

Year ended

​

​

​

December 31, 

​

​

    

2023

    

2022

    

2021

 

Numerator:

​

​

​

​

​

​

​

​

​

​

Net income (loss) attributable to AXT, Inc.

​

$

(17,881)

​

$

15,811

​

$

14,575

​

Less: Preferred stock dividends

​

 

(177)

​

 

(177)

​

 

(177)

​

Net income (loss) available to common stockholders

​

$

(18,058)

​

$

15,634

​

$

14,398

​

Denominator:

​

​

​

​

​

​

​

​

​

​

Denominator for basic net income (loss) per share - weighted-average common shares

​

 

42,643

​

 

42,104

​

 

41,367

​

Effect of dilutive securities:

​

​

​

​

​

​

​

​

​

​

Common stock options

​

 

—

​

 

333

​

 

803

​

Restricted stock awards

​

 

—

​

 

278

​

 

550

​

Denominator for dilutive net income (loss) per common shares

​

 

42,643

​

 

42,715

​

 

42,720

​

Net income (loss) attributable to AXT, Inc. per common share:

​

​

​

​

​

​

​

​

​

​

Basic

​

$

(0.42)

​

$

0.37

​

$

0.35

​

Diluted

​

$

(0.42)

​

$

0.37

​

$

0.34

​

​

​

​

​

​

​

​

​

​

​

​

Options excluded from diluted net income (loss) per share as the impact is anti-dilutive

​

 

1,198

​

 

220

​

 

21

​

Restricted stock excluded from diluted net income (loss) per share as the impact is anti-dilutive

​

 

1,258

​

 

291

​

 

118

​

​
v3.24.0.1
Segment Information and Foreign Operations (Tables)
 12 Months Ended
Dec. 31, 2023
Segment Information and Foreign Operations  
Revenues reported by product type

The following table represents revenue amounts (in thousands) by product type:

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

December 31, 

​

​

2023

    

2022

    

2021

 

Product Type:

​

​

​

​

​

​

​

​

​

Substrates

$

47,466

​

$

111,094

​

$

103,026

​

Raw materials and others

 

28,329

​

 

30,024

​

 

34,367

​

Total

$

75,795

​

$

141,118

​

$

137,393

​
Revenue reported for products shipped to customers in the corresponding geographic region

The following table represents revenue amounts (in thousands) reported for products shipped to customers in the corresponding geographic region:

​

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

​

December 31, 

​

 

​

2023

    

2022

    

2021

 

​

Geographical region:

​

​

​

​

​

​

​

​

​

​

China

$

39,778

​

$

55,414

​

$

67,394

​

​

Taiwan

​

8,651

​

​

28,780

​

​

16,841

​

​

Japan

​

4,641

​

​

11,724

​

​

10,112

​

​

Asia Pacific (excluding China, Taiwan and Japan)

​

3,814

​

​

4,188

​

​

7,540

​

​

Europe (primarily Germany)

​

12,315

​

​

20,592

​

​

23,069

​

​

North America (primarily the United States)

 

6,596

​

 

20,420

​

 

12,437

​

​

Total

$

75,795

​

$

141,118

​

$

137,393

​
Long-lived assets by geographic region

Long-lived assets consist primarily of property, plant and equipment, and operating lease right-of-use assets are attributed to the geographic location in which they are located. Long-lived assets, net of depreciation, by geographic region were as follows (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

​

​

As of December 31, 

​

​

 

2023

    

2022

 

Long-lived assets by geographic region, net of depreciation:

​

​

​

​

​

​

​

North America

​

$

1,631

​

$

346

​

China

​

 

167,516

​

 

162,432

​

​

​

$

169,147

​

$

162,778

​

​
v3.24.0.1
Other income (expense), net (Tables)
 12 Months Ended
Dec. 31, 2023
Other income (expense), net  
Schedule of components of other income, net

The components of other income (expense), net are summarized below (in thousands):

​

​

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

December 31, 

​

​

2023

    

2022

    

2021

Foreign exchange gain (loss)

​

$

169

​

$

1,573

​

$

(434)

Income from local China government subsidy

​

​

2,557

​

​

1,710

​

​

1,125

Other income (expense)

​

​

(547)

​

​

204

​

​

(182)

​

​

$

2,179

​

$

3,487

​

$

509

​

​

​

​

​

​

​

​

​

​

​
v3.24.0.1
Commitments and Contingencies (Tables)
 12 Months Ended
Dec. 31, 2023
Commitments and Contingencies  
Summary of maturities of our operating lease liabilities

As of December 31, 2023, the maturities of our operating lease liabilities (excluding short-term leases) are as follows (in thousands):

​

​

​

Maturity of Lease Liabilities

    

​

2024

$

591

2025

​

604

2026

​

618

2027

​

633

2028

​

614

Thereafter

​

153

Total minimum lease payments

​

3,213

Less: Interest

​

(404)

Present value of lease obligations

​

2,809

Less: Current portion, included in accrued liabilities

​

(458)

Long-term portion of lease obligations

$

2,351
Schedule of weighted-average remaining lease term and the weighted-average discount rate of operating leases

​

​

​

​

​

​

​

​

​

December 31, 

​

December 31, 

​

​

​

2023

​

2022

​

Weighted-average remaining lease term (years)

​

5.22

​

5.89

​

Weighted-average discount rate

​

5.14

%

4.61

%
Schedule of supplemental cash flow information related to leases

Supplemental cash flow information related to leases where we are the lessee is as follows (in thousands):

​

​

​

​

​

​

​

​

​

​

Year Ended

​

​

​

December 31, 

​

​

​

2023

​

2022

​

Cash paid for amounts included in the measurement of lease liabilities:

​

​

​

​

​

​

​

Operating cash flows from operating leases

​

$

578

​

$

574

​
Summary of components of lease expense

The components of lease expense are as follows (in thousands) within our consolidated statements of operations:

​

​

​

​

​

​

​

​

​

Year Ended

​

​

December 31, 

​

​

2023

​

2022

Operating lease

​

$

548

​

$

530

Short-term lease expense

​

​

143

​

​

137

Total

​

$

691

​

$

667
v3.24.0.1
Unaudited Quarterly Consolidated Financial Data (Tables)
 12 Months Ended
Dec. 31, 2023
Unaudited Quarterly Consolidated Financial Data  
Schedule of unaudited quarterly consolidated financial data

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Quarter

 

​

    

First

    

Second

    

Third

    

Fourth

 

​

​

(in thousands, except per share data)

 

2023:

​

​

​

​

​

​

​

​

​

​

​

​

​

Revenue

​

$

19,405

​

$

18,595

​

$

17,366

​

$

20,429

​

Gross profit

​

 

5,110

​

 

1,715

​

 

1,866

​

 

4,627

​

Net income attributable to AXT, Inc.

​

 

(3,348)

​

 

(5,089)

​

 

(5,823)

​

 

(3,621)

​

Net income attributable to AXT, Inc. per share, basic

​

$

(0.08)

​

$

(0.12)

​

$

(0.14)

​

$

(0.09)

​

Net income attributable to AXT, Inc. per share, diluted

​

$

(0.08)

​

$

(0.12)

​

$

(0.14)

​

$

(0.09)

​

2022:

​

​

​

​

​

​

​

​

​

​

​

​

​

Revenue

​

$

39,653

​

$

39,487

​

$

35,183

​

$

26,795

​

Gross profit

​

 

13,308

​

 

15,435

​

 

14,782

​

 

8,596

​

Net income (loss) attributable to AXT, Inc.

​

 

3,165

​

 

5,546

​

 

5,759

​

 

1,341

​

Net income (loss) attributable to AXT, Inc. per share, basic

​

$

0.07

​

$

0.13

​

$

0.14

​

$

0.03

​

Net income (loss) attributable to AXT, Inc. per share, diluted

​

$

0.07

​

$

0.13

​

$

0.13

​

$

0.03

​

​
v3.24.0.1
Redeemable Noncontrolling Interests (Tables)
 12 Months Ended
Dec. 31, 2023
Redeemable Noncontrolling Interests  
Components of the change in redeemable noncontrolling interests

The components of the change in redeemable noncontrolling interests for the years ended December 31, 2023 and 2022 are presented in the following table (in thousands):

​

​

​

Balance as of January 1, 2022

$

50,385

Investment in subsidiary with redeemable noncontrolling interest

​

471

Equity issuance costs incurred

​

(2,699)

Stock-based compensation attributable to redeemable noncontrolling interests

​

(36)

Net income attributable to redeemable noncontrolling interests

​

1,598

Effect of foreign currency translation on redeemable noncontrolling interests

​

(3,962)

Effect of foreign currency translation attributable to redeemable noncontrolling interests

​

(911)

Balance as of December 31, 2022

​

44,846

Investment in subsidiary with redeemable noncontrolling interest

​

155

Equity issuance costs incurred

​

(880)

Stock-based compensation attributable to redeemable noncontrolling interests

​

52

Net loss attributable to redeemable noncontrolling interests

​

(920)

Effect of foreign currency translation on redeemable noncontrolling interests

​

(1,260)

Effect of foreign currency translation attributable to redeemable noncontrolling interests

​

(330)

Balance as of December 31, 2023

$

41,663

​
v3.24.0.1
The Company and Summary of Significant Accounting Policies - The Company (Details)
 12 Months Ended
Dec. 31, 2023
item
segment
The Company and Summary of Significant Accounting Policies  
Number of product lines | segment 2
Minimum  
The Company and Summary of Significant Accounting Policies  
Temperature in C 500
Maximum  
The Company and Summary of Significant Accounting Policies  
Temperature in C 1,500
Sales Revenue, Net [Member] | Customer concentration | Specialty Material Substrates  
The Company and Summary of Significant Accounting Policies  
Revenue by product line (as a percent) 63.00%
Sales Revenue, Net [Member] | Customer concentration | Raw Materials  
The Company and Summary of Significant Accounting Policies  
Revenue by product line (as a percent) 37.00%
v3.24.0.1
The Company and Summary of Significant Accounting Policies- Principles of Consolidation (Details)
 1 Months Ended 12 Months Ended
May 31, 2023
USD ($)
Jan. 25, 2021
USD ($)
Dec. 31, 2023
USD ($)
Aug. 31, 2023
USD ($)
May 31, 2023
USD ($)
Jan. 31, 2023
USD ($)
Aug. 31, 2022
USD ($)
Jul. 31, 2022
USD ($)
May 31, 2022
USD ($)
Apr. 30, 2022
USD ($)
Jan. 31, 2022
USD ($)
Jun. 30, 2021
USD ($)
May 31, 2021
USD ($)
Feb. 28, 2021
USD ($)
Jan. 31, 2021
USD ($)
Dec. 31, 2023
USD ($)
company
Dec. 31, 2022
USD ($)
company
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Sep. 30, 2023
USD ($)
Jul. 31, 2023
USD ($)
Sep. 30, 2022
Oct. 31, 2021
USD ($)
Sep. 30, 2021
USD ($)
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Number of equity method investments | company                               3 6              
Investments, equity method     $ 12,476,000                         $ 12,476,000 $ 12,720,000              
Proceeds from sale of equity method investments                               827,000                
Payment for investment                               $ 2,538,000                
Sale of subsidiary shares to noncontrolling interests                                   $ 1,151,000            
Percentage of equity interest sold                               15.00%                
AXT-Tongmei, Inc | Disposal Group, Disposed of by Sale, Not Discontinued Operations                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Cash consideration                       $ 1,000,000                        
Minority investors                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Loan amount $ 300,000       $ 300,000 $ 200,000                                    
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Loan from related party                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Increase in redeemable noncontrolling interests                 $ 100,000                              
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Loan from related party | ChaoYang Xinshuo                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Loan amount                                             $ 1,000,000.0 $ 900,000
Sale of subsidiary shares to noncontrolling interests                   $ 1,900,000                            
Amount paid to subsidiary                 600,000 700,000                            
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Loan from related party | Beijing Tongmei Xtal Technology                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Sale of subsidiary shares to noncontrolling interests                   2,600,000                            
Amount paid to subsidiary                 800,000 1,100,000                            
Increase in noncontrolling interest                 $ 1,400,000   $ 2,200,000                          
Increase in redeemable noncontrolling interests                     $ 200,000                          
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Investment value, agreement amount                         $ 1,800,000 $ 3,000,000.0                    
Investments, equity method                           $ 1,800,000                    
Ownership (as a percent)               58.50% 58.50%   58.50%   58.50% 58.50%                    
Initial funding                         $ 1,500,000 $ 1,500,000                    
Increase in noncontrolling interest               $ 610,000                                
Further investment               600,000                                
Redeemable noncontrolling interest increased               57,000                                
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Loan from related party                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Sale of subsidiary shares to noncontrolling interests                   4,500,000                            
ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Investment value, agreement amount                   4,400,000                            
Investments, equity method                   $ 3,300,000                            
Ownership (as a percent)       75.00%           75.00%                            
Initial funding             $ 334,000                                  
Increase in noncontrolling interest       $ 200,000     406,000                                  
Increase in redeemable noncontrolling interests       44,000                                        
Redeemable noncontrolling interest increased             73,000                                  
ChaoYang KaiMei Quartz Co., Ltd                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Investment value, agreement amount                   $ 7,600,000                            
Investments, equity method     $ 3,154,000 600,000   900,000       $ 3,000,000.0           $ 3,154,000 827,000     $ 2,300,000 $ 600,000      
Ownership (as a percent)     40.00%             40.00%           40.00%                
Initial funding               2,200,000                                
Investment amount               900,000                                
Additional investment                                       $ 5,600,000        
Payment for investment     $ 600,000                                          
Emeishan Jia Mei High Purity Metals Co., Ltd Investment                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Investments, equity method                                 $ 418,000              
Ownership (as a percent) 25.00%   10.00%   25.00%                     10.00%                
Proceeds from sale of equity method investments $ 10       $ 827,000                                      
Percentage of equity interest sold 15.00%                             15.00%                
Percentage of ownership, cost method 10.00%   10.00%   10.00%                     10.00%                
ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Increase in noncontrolling interest         $ 400,000 200,000                                    
Increase in redeemable noncontrolling interests         75,000 36,000                                    
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Percentage of outstanding shares                                     33.00%          
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment | Beijing Boyu Semiconductor Vessel Craftwork Technology Co Ltd                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Private equity ownership percentage                                     7.59%          
Beijing Tongmei Xtal Technology                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Percentage of ownership                       85.50%                        
Percentage of outstanding shares   7.28%                                       14.50%    
Private equity ownership percentage   7.28%                             14.50%              
Percentage of key managers and contributors purchased                                     0.40%          
Investment in new facility   $ 49,000,000                                 $ 48,100,000          
Raised additional capital                             $ 1,500,000                  
Transaction results in increase to noncontrolling interests                       $ 1,200,000                        
Transaction results in increase to redeemable noncontrolling interests                       $ 1,200,000                        
Increase in redeemable noncontrolling interests                             $ 1,500,000       $ 48,100,000          
Beijing Tongmei Xtal Technology | Beijing Boyu Semiconductor Vessel Craftwork Technology Co Ltd                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Investment amount                           $ 900,000                    
Private equity ownership percentage                                     7.59%          
Beijing Tongmei Xtal Technology | Nanjing JinMei Gallium Co., Ltd                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Private equity ownership percentage                                     0.0038%          
Beijing Tongmei Xtal Technology | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Loan amount                     $ 1,400,000             $ 1,400,000            
Beijing Tongmei Xtal Technology | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Loan from related party                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Increase in noncontrolling interest                 $ 1,400,000                              
Beijing Tongmei Xtal Technology | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Initial funding               800,000                                
Investment amount                         $ 900,000                      
Further investment               $ 800,000                                
Nanjing JinMei Gallium Co., Ltd Investment                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Percentage of outstanding shares                                     8.50%          
Nanjing JinMei Gallium Co., Ltd Investment | Nanjing JinMei Gallium Co., Ltd                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Private equity ownership percentage                                     0.38%          
Nanjing JinMei Gallium Co., Ltd Investment | Emeishan Jia Mei High Purity Metals Co., Ltd Investment                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Ownership (as a percent)     25.00%                         25.00%                
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Initial funding             $ 1,000,000.0                                  
ChaoYang JinMei Gallium Ltd. | ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Loan amount           $ 500,000                                    
ChaoYang JinMei Gallium Ltd. | ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd. | ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                                
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]                                                
Loan amount $ 1,000,000.0     $ 600,000 $ 1,000,000.0                                      
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Foreign Exchange Transaction Gains/Lossess      
Foreign exchange gain (loss) $ 169,000 $ 1,573,000 $ (434,000)
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Revenue Recognition (Details)
 3 Months Ended 12 Months Ended
Dec. 31, 2023
USD ($)
Dec. 31, 2022
USD ($)
Dec. 31, 2023
USD ($)
segment
Dec. 31, 2022
USD ($)
Revenue        
Contract liabilities $ 305,000 $ 338,000 $ 305,000 $ 338,000
Amounts included in contract balances $ 9,000 $ 22,000 $ 287,000 $ 760,000
Number of operating segments | segment     1  
Revenue, Practical Expedient, Incremental Cost of Obtaining Contract     true  
Revenue, Practical Expedient, Financing Component     true  
Revenue, Practical Expedient, Remaining Performance Obligation     true  
Maximum        
Revenue Recognition        
Sales commissions benefit period     1 year  
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Risks and Concentration of Credit Risk (Details) - customer
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Customer concentration        
The Company and Summary of Significant Accounting Policies        
Number of customers representing significant share 0      
Accounts Receivable [Member]        
The Company and Summary of Significant Accounting Policies        
Number of customers representing significant share 0      
Accounts Receivable [Member] | Customer concentration        
The Company and Summary of Significant Accounting Policies        
Number of customers representing significant share   2    
Raw Materials | Revenue [Member]        
The Company and Summary of Significant Accounting Policies        
Number of customers representing significant share   2 1 1
Major Customer One [Member] | Revenue [Member] | Customer concentration        
The Company and Summary of Significant Accounting Policies        
Number of customers representing significant share   1    
Percentage share generated by major customers (in hundredths) 10.00% 15.00% 10.00%  
Major Customer One [Member] | Accounts Receivable [Member] | Customer concentration        
The Company and Summary of Significant Accounting Policies        
Percentage share generated by major customers (in hundredths)   10.00%    
Top Five Major Customers [Member] | Revenue [Member]        
The Company and Summary of Significant Accounting Policies        
Number of customers representing significant share 5 5 5  
Top Five Major Customers [Member] | Revenue [Member] | Customer concentration        
The Company and Summary of Significant Accounting Policies        
Percentage share generated by major customers (in hundredths) 25.00% 34.00% 26.00%  
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Restricted Cash (Details) - USD ($)
$ in Thousands
 1 Months Ended 12 Months Ended
Dec. 31, 2023
Jun. 30, 2023
Jan. 31, 2023
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
May 31, 2022
Apr. 30, 2022
Cash and Cash Equivalents [Line Items]                
Proceeds from short-term bank loans       $ 56,470 $ 53,078 $ 20,543    
Restricted cash $ 12,362     12,362 6,400      
Bank Of Beijing                
Cash and Cash Equivalents [Line Items]                
Maximum borrowing capacity             $ 3,400  
Secured debt | Bank Of Beijing                
Cash and Cash Equivalents [Line Items]                
Time deposit         $ 2,500   $ 1,000 $ 2,900
Proceeds from short-term bank loans     $ 2,300          
Secured debt | Bank Of China                
Cash and Cash Equivalents [Line Items]                
Time deposit     3,000          
Proceeds from short-term bank loans     $ 2,900          
Secured debt | June 2023 Bank Loan Two                
Cash and Cash Equivalents [Line Items]                
Time deposit 3,900     3,900        
Proceeds from short-term bank loans       3,500        
Secured debt | June 2023 Bank Loan One                
Cash and Cash Equivalents [Line Items]                
Time deposit 1,500 $ 1,500   $ 1,500        
Proceeds from short-term bank loans $ 1,400 $ 1,400            
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Accounts Receivable and Allowance for Doubtful Accounts and Sales Returns (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
The Company and Summary of Significant Accounting Policies    
Accounts receivable $ 19,256,000 $ 29,252,000
Allowance for Doubtful Accounts    
The Company and Summary of Significant Accounting Policies    
Valuation allowance balance 579,000 307,000
Increase/ (decrease) in allowance for doubtful accounts 272,000 177,000
Allowance for Sales Returns    
The Company and Summary of Significant Accounting Policies    
Valuation allowance balance 39,000 112,000
Allowance utilized 39,000 112,000
Additional reduction $ 34,000 $ 176,000
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Warranty Reserve (Details) - USD ($)
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Warranty Reserve      
Accrued product warranties $ 703,000 $ 669,000 $ 743,000
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Property, Plant and Equipment (Details)
Dec. 31, 2023
Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 1 year
Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 39 years 6 months
Computers [Member] | Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 3 years
Computers [Member] | Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 5 years
Office Equipment [Member] | Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 3 years
Office Equipment [Member] | Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 5 years
Software [Member] | Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 3 years
Software [Member] | Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 5 years
Furniture and Fixtures [Member] | Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 3 years
Furniture and Fixtures [Member] | Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 5 years
Automobiles [Member] | Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 5 years
Automobiles [Member] | Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 10 years
Leasehold improvements  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 10 years
Building improvements  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 10 years
Machinery and equipment | Minimum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 1 year
Machinery and equipment | Maximum  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 20 years
Building  
Property, Plant and Equipment  
Property, plant and equipment, estimated economic life 39 years 6 months
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Impairment of Investments (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
The Company and Summary of Significant Accounting Policies      
Impairment charge $ 1,900,000 $ 0 $ 0
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Segment Reporting (Details)
 12 Months Ended
Dec. 31, 2023
segment
The Company and Summary of Significant Accounting Policies  
Number of operating segments 1
v3.24.0.1
The Company and Summary of Significant Accounting Policies - Comprehensive Income (loss) (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Accumulated other comprehensive loss:    
Accumulated other comprehensive income (loss) attributable to AXT, Inc. $ (5,999) $ (3,118)
Accumulated other comprehensive income including noncontrolling interest    
Accumulated other comprehensive loss:    
Unrealized loss on investments, net (20) (303)
Cumulative translation adjustment (6,530) (3,042)
Accumulated other comprehensive income (loss) attributable to AXT, Inc. (6,550) (3,345)
Accumulated other comprehensive income attributable to noncontrolling interest    
Accumulated other comprehensive loss:    
Less: Cumulative translation adjustment attributable to noncontrolling interests and redeemable noncontrolling interests $ (551) $ (227)
v3.24.0.1
Cash, Cash Equivalents and Investments (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Cash, cash equivalents and investments [Abstract]        
Cash and restricted cash $ 50,114,000 $ 41,348,000    
Cash equivalents [Abstract]        
Total cash, restricted cash and cash equivalents 50,114,000 41,348,000 $ 36,763,000 $ 72,602,000
Amortized Cost 2,160,000 11,760,000    
Cash, restricted cash, cash equivalents and investments, amortized costs 52,274,000 53,108,000    
Gross Unrealized (Loss) (20,000) (303,000)    
Fair Value 2,140,000 11,457,000    
Cash, restricted cash, cash equivalents and investments, fair value. 52,254,000 52,805,000    
Contractual maturities on investments, amortized cost basis [Abstract]        
Due within 1 year 2,160,000 9,600,000    
Due after 1 through 5 years   2,160,000    
Investments, amortized cost 2,160,000 11,760,000    
Contractual maturities on investments, fair value basis [Abstract]        
Due within 1 year 2,140,000 9,339,000    
Due after 1 through 5 years   2,118,000    
Investments, fair value 2,140,000 11,457,000    
Debt Securities, Available-for-sale, Unrealized Loss 20,000      
Impairment charge 1,900,000 0 $ 0  
Investments.        
Cash equivalents [Abstract]        
Amortized Cost 2,160,000 11,760,000    
Gross Unrealized (Loss) (20,000) (303,000)    
Fair Value 2,140,000 11,457,000    
Contractual maturities on investments, amortized cost basis [Abstract]        
Investments, amortized cost 2,160,000 11,760,000    
Contractual maturities on investments, fair value basis [Abstract]        
Investments, fair value 2,140,000 11,457,000    
Certificates of deposit.        
Cash equivalents [Abstract]        
Amortized Cost 2,160,000 6,440,000    
Gross Unrealized (Loss) (20,000) (175,000)    
Fair Value 2,140,000 6,265,000    
Contractual maturities on investments, amortized cost basis [Abstract]        
Investments, amortized cost 2,160,000 6,440,000    
Contractual maturities on investments, fair value basis [Abstract]        
Investments, fair value $ 2,140,000 6,265,000    
Corporate bonds        
Cash equivalents [Abstract]        
Amortized Cost   5,320,000    
Gross Unrealized (Loss)   (128,000)    
Fair Value   5,192,000    
Contractual maturities on investments, amortized cost basis [Abstract]        
Investments, amortized cost   5,320,000    
Contractual maturities on investments, fair value basis [Abstract]        
Investments, fair value   $ 5,192,000    
v3.24.0.1
Cash, Cash Equivalents and Investments - Investment Category and Length (Details)
 1 Months Ended 12 Months Ended
May 31, 2023
USD ($)
Dec. 31, 2023
USD ($)
Jun. 30, 2023
USD ($)
May 31, 2023
USD ($)
Jan. 31, 2023
USD ($)
Dec. 31, 2023
USD ($)
company
Dec. 31, 2022
USD ($)
company
Dec. 31, 2021
USD ($)
May 31, 2022
USD ($)
Apr. 30, 2022
USD ($)
Summary of fair value and gross unrealized losses related to available-for-sale securities [Abstract]                    
Fair value, in loss position less than twelve months             $ 2,118,000      
Gross unrealized (loss), in loss position less than twelve months             (42,000)      
Fair value, in loss position greater than twelve months   $ 2,140,000       $ 2,140,000 8,988,000      
Gross unrealized (loss), in loss position greater than twelve months   (20,000)       (20,000) (261,000)      
Fair value, total in loss position   2,140,000       2,140,000 11,106,000      
Gross unrealized (loss), total in loss position   (20,000)       (20,000) (303,000)      
Restricted Cash                    
Proceeds from short-term bank loans           56,470,000 53,078,000 $ 20,543,000    
Restricted cash   12,362,000       12,362,000 6,400,000      
Minority Investments                    
Investments, equity method   12,476,000       $ 12,476,000 $ 12,720,000      
Number of equity method investments | company           3 6      
Proceeds from sale of equity method investments           $ 827,000        
Investment, cost method   551,000       551,000 $ 1,887,000      
Loss on sale of equity investment           (166,000)        
Bank Of Beijing                    
Restricted Cash                    
Maximum borrowing capacity                 $ 3,400,000  
Bank Of Beijing | Secured debt                    
Restricted Cash                    
Time deposit             2,500,000   $ 1,000,000.0 $ 2,900,000
Proceeds from short-term bank loans         $ 2,300,000          
June 2023 bank loan two | Secured debt                    
Restricted Cash                    
Time deposit   3,900,000       3,900,000        
Proceeds from short-term bank loans           3,500,000        
June 2023 bank loan one | Secured debt                    
Restricted Cash                    
Time deposit   1,500,000 $ 1,500,000     $ 1,500,000        
Proceeds from short-term bank loans   $ 1,400,000 $ 1,400,000              
Bank Of China | Secured debt                    
Restricted Cash                    
Time deposit         3,000,000.0          
Proceeds from short-term bank loans         $ 2,900,000          
Emeishan Jia Mei High Purity Metals Co., Ltd Investment                    
Minority Investments                    
Investments, equity method             418,000      
Ownership (as a percent) 25.00% 10.00%   25.00%   10.00%        
Proceeds from sale of equity method investments $ 10     $ 827,000            
Investment, cost method   $ 551,000       $ 551,000        
Equity ownership percentage 10.00% 10.00%   10.00%   10.00%        
Loss on sale of equity investment       $ 575,000   $ 575,000        
Beijing JiYa Semiconductor Material Co., Ltd Investment                    
Minority Investments                    
Investments, equity method   $ 3,806,000       $ 3,806,000 6,381,000      
Ownership (as a percent)   39.00%       39.00%        
Certificates of deposit.                    
Summary of fair value and gross unrealized losses related to available-for-sale securities [Abstract]                    
Fair value, in loss position less than twelve months             2,118,000      
Gross unrealized (loss), in loss position less than twelve months             (42,000)      
Fair value, in loss position greater than twelve months   $ 2,140,000       $ 2,140,000 4,146,000      
Gross unrealized (loss), in loss position greater than twelve months   (20,000)       (20,000) (133,000)      
Fair value, total in loss position   2,140,000       2,140,000 6,264,000      
Gross unrealized (loss), total in loss position   (20,000)       (20,000) (175,000)      
Corporate bonds                    
Summary of fair value and gross unrealized losses related to available-for-sale securities [Abstract]                    
Fair value, in loss position greater than twelve months             4,842,000      
Gross unrealized (loss), in loss position greater than twelve months             (128,000)      
Fair value, total in loss position             4,842,000      
Gross unrealized (loss), total in loss position             (128,000)      
Other assets                    
Minority Investments                    
Investments, equity method   $ 12,500,000       $ 12,500,000 $ 14,600,000      
v3.24.0.1
Cash, Cash Equivalents and Investments - Recurring Basis (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Assets, Fair Value Disclosure [Abstract]    
Investments, amortized cost $ 2,140,000 $ 11,457,000
Fair Value, Transfer Between Level 1 and Level 2, Description and Policy [Abstract]    
Transfer from Level 1 to Level 2 , assets 0  
Transfers into Level 3, assets 0 0
Transfer out of Level 3, assets 0 0
Recurring    
Assets, Fair Value Disclosure [Abstract]    
Total 2,140,000 11,457,000
Recurring | Certificates of deposit.    
Assets, Fair Value Disclosure [Abstract]    
Cash and cash equivalents, fair value disclosure 2,140,000 6,265,000
Recurring | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Investments, amortized cost   5,192,000
Recurring | Significant Other Observable Inputs (Level 2)    
Assets, Fair Value Disclosure [Abstract]    
Total 2,140,000 11,457,000
Recurring | Significant Other Observable Inputs (Level 2) | Certificates of deposit.    
Assets, Fair Value Disclosure [Abstract]    
Cash and cash equivalents, fair value disclosure $ 2,140,000 6,265,000
Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Investments, amortized cost   $ 5,192,000
v3.24.0.1
Inventories (Details) - USD ($)
Dec. 31, 2023
Dec. 31, 2022
Inventories    
Raw materials $ 32,910,000 $ 46,476,000
Work in process 50,008,000 39,956,000
Finished goods 3,585,000 3,197,000
Inventories, Total 86,503,000 89,629,000
Inventory reserve 21,900,000 24,700,000
Excess and obsolete inventory $ 78,000 $ 47,000
v3.24.0.1
Related Party Transactions (Details) - USD ($)
 1 Months Ended 12 Months Ended
Jan. 31, 2023
Sep. 30, 2022
Jul. 31, 2022
May 31, 2022
Apr. 30, 2022
Jan. 31, 2022
Dec. 31, 2021
Oct. 31, 2021
Sep. 30, 2021
Jan. 31, 2021
Dec. 31, 2023
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2022
May 31, 2021
Feb. 28, 2021
Related Party Transaction [Line Items]                                
Amount payable to related party                     $ 9,617,000     $ 10,084,000    
Sale of subsidiary shares to noncontrolling interests                       $ 1,151,000        
Beijing Tongmei Xtal Technology                                
Related Party Transaction [Line Items]                                
Increase in redeemable noncontrolling interests                   $ 1,500,000     $ 48,100,000      
Loan from related party | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                
Related Party Transaction [Line Items]                                
Increase in redeemable noncontrolling interests       $ 100,000                        
Loan from related party | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Beijing Tongmei Xtal Technology                                
Related Party Transaction [Line Items]                                
Increase in noncontrolling interest       1,400,000                        
ChaoYang XinMei                                
Related Party Transaction [Line Items]                                
Sale of subsidiary shares to noncontrolling interests         $ 4,500,000                      
Donghai County Dongfang High Purity Electronic Materials Co., Ltd | Raw materials purchases from related party | Accounts payable | Chao Yang Tongmei Xtal Technology Co., Ltd.                                
Related Party Transaction [Line Items]                                
Amount payable to related party                     0     $ 103,000    
ChaoYang Xinshuo | Loan from related party | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                
Related Party Transaction [Line Items]                                
Amount of transaction               $ 1,000,000.0 $ 900,000              
Short-term loan from noncontrolling interest             $ 1,900,000         $ 1,900,000        
Amount paid to subsidiary       600,000 700,000                      
Sale of subsidiary shares to noncontrolling interests         1,900,000                      
Beijing Tongmei Xtal Technology | Related party loan | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                
Related Party Transaction [Line Items]                                
Amount of transaction             $ 1,400,000                  
Beijing Tongmei Xtal Technology | Loan from related party | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                
Related Party Transaction [Line Items]                                
Amount of transaction           $ 1,400,000                    
Short-term loan from noncontrolling interest           0                    
Amount paid to subsidiary       800,000 1,100,000                      
Increase in redeemable noncontrolling interests           200,000                    
Increase in noncontrolling interest       $ 1,400,000   $ 2,200,000                    
Sale of subsidiary shares to noncontrolling interests         2,600,000                      
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                
Related Party Transaction [Line Items]                                
Ownership (as a percent)     58.50% 58.50%   58.50%                 58.50% 58.50%
Increase in noncontrolling interest     $ 610,000                          
Further investment     600,000                          
Redeemable noncontrolling interest increased     57,000                          
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Beijing Tongmei Xtal Technology                                
Related Party Transaction [Line Items]                                
Further investment     $ 800,000                          
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | ChaoYang KaiMei Quartz Co., Ltd                                
Related Party Transaction [Line Items]                                
Amount of transaction   $ 1,500,000                            
Proceeds from related party $ 1,500,000                              
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Prepaid expenses and other current assets | ChaoYang KaiMei Quartz Co., Ltd                                
Related Party Transaction [Line Items]                                
Amount of transaction                     $ 0          
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Loan from related party                                
Related Party Transaction [Line Items]                                
Sale of subsidiary shares to noncontrolling interests         $ 4,500,000                      
v3.24.0.1
Property, Plant and Equipment, Net (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Property, plant and equipment    
Property, plant and equipment, net $ 166,348 $ 161,017
Machinery and equipment    
Property, plant and equipment    
Property, plant and equipment, gross 65,918 62,797
Less: accumulated depreciation and amortization (42,112) (38,477)
Building    
Property, plant and equipment    
Property, plant and equipment, gross 125,786 118,550
Less: accumulated depreciation and amortization (23,339) (20,403)
Leasehold improvements    
Property, plant and equipment    
Property, plant and equipment, gross 7,596 7,430
Less: accumulated depreciation and amortization (5,984) (5,559)
Construction in progress    
Property, plant and equipment    
Property, plant and equipment, gross 38,483 36,679
Construction in progress Dingxin and Kazuo locations    
Property, plant and equipment    
Property, plant and equipment, gross 31,200 27,200
Construction in progress manufacturing equipment purchases    
Property, plant and equipment    
Property, plant and equipment, gross 3,100 5,400
Construction in progress other consolidated subsidiaries    
Property, plant and equipment    
Property, plant and equipment, gross $ 4,200 $ 4,100
v3.24.0.1
Investments in Privately-held Raw Material Companies (Details) - USD ($)
 1 Months Ended 12 Months Ended
May 31, 2023
Jan. 25, 2021
Nov. 30, 2023
May 31, 2023
Apr. 30, 2023
Jan. 31, 2023
Aug. 31, 2022
Jul. 31, 2022
Jun. 30, 2022
Apr. 30, 2022
Jun. 30, 2021
Jan. 31, 2021
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Sep. 30, 2023
Aug. 31, 2023
Jul. 31, 2023
Sep. 30, 2022
Summary of investments                                        
Investments, equity method                         $ 12,476,000 $ 12,720,000            
Investment, cost method                         551,000 1,887,000            
Dividend received                         $ 4,316,000 1,608,000 $ 774,000          
Percentage of equity interest sold                         15.00%              
Proceeds from sale of equity method investments                         $ 827,000              
Loss on sale of equity investment                         (166,000)              
Fair value of the consideration received                         779,000              
3rd Party Investor                                        
Summary of investments                                        
Percentage of equity interest sold     46.00%                                  
Other assets                                        
Summary of investments                                        
Investments, equity method                         $ 12,500,000 14,600,000            
Donghai County Dongfang High Purity Electronic Materials Co., Ltd Investment                                        
Summary of investments                                        
Investment, cost method                           1,887,000            
Percentage of ownership, equity method     46.00%                                  
Percentage of ownership, cost method     0.00%                   0.00%              
Percentage of equity interest sold     46.00%                   46.00%              
Loss on sale of equity investment                         $ (1,125,000)              
Fair value of the consideration received     $ 600,000                   585,000              
Beijing JiYa Semiconductor Material Co., Ltd Investment                                        
Summary of investments                                        
Investments, equity method                         $ 3,806,000 6,381,000            
Percentage of ownership, equity method                         39.00%              
Dividends received     $ 500,000   $ 2,000,000.0   $ 100,000                          
PRC subsidiaries and PRC raw material joint ventures                                        
Summary of investments                                        
Dividends received                         $ 4,300,000 2,900,000 $ 774,000          
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment                                        
Summary of investments                                        
Dividends received                 $ 1,300,000                      
Xiaoyi XingAn Gallium Co., Ltd.                                        
Summary of investments                                        
Investments, equity method                         $ 5,516,000 5,094,000            
Percentage of ownership, equity method                         25.00%              
Dividends received               $ 1,500,000   $ 1,800,000 $ 774,000                  
ChaoYang KaiMei Quartz Co., Ltd                                        
Summary of investments                                        
Investments, equity method           $ 900,000       $ 3,000,000.0     $ 3,154,000 827,000     $ 2,300,000 $ 600,000 $ 600,000  
Percentage of ownership, equity method                   40.00%     40.00%              
Emeishan Jia Mei High Purity Metals Co., Ltd Investment                                        
Summary of investments                                        
Investments, equity method                           $ 418,000            
Investment, cost method                         $ 551,000              
Percentage of ownership, equity method 25.00%     25.00%                 10.00%              
Percentage of ownership, cost method 10.00%     10.00%                 10.00%              
Percentage of equity interest sold 15.00%                       15.00%              
Proceeds from sale of equity method investments $ 10     $ 827,000                                
Loss on sale of equity investment       575,000                 $ 575,000              
Nanjing JinMei Gallium Co., Ltd Investment                                        
Summary of investments                                        
Percentage of outstanding shares                               8.50%        
Nanjing JinMei Gallium Co., Ltd Investment | Beijing JiYa Semiconductor Material Co., Ltd Investment                                        
Summary of investments                                        
Percentage of ownership, equity method                         39.00%              
Nanjing JinMei Gallium Co., Ltd Investment | Emeishan Jia Mei High Purity Metals Co., Ltd Investment                                        
Summary of investments                                        
Percentage of ownership, equity method                         25.00%              
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment                                        
Summary of investments                                        
Percentage of outstanding shares                               33.00%        
Beijing Tongmei Xtal Technology                                        
Summary of investments                                        
Percentage of ownership, consolidated method (in hundredths)                     85.50%                  
Percentage of outstanding shares   7.28%                                   14.50%
Private equity ownership percentage   7.28%                       14.50%            
Percentage of key managers and contributors purchased                               0.40%        
Increase in redeemable noncontrolling interests                       $ 1,500,000       $ 48,100,000        
Investments, government approved   $ 49,000,000                                    
Nanjing JinMei Gallium Co., Ltd | Nanjing JinMei Gallium Co., Ltd Investment                                        
Summary of investments                                        
Private equity ownership percentage                               0.38%        
Nanjing JinMei Gallium Co., Ltd | Beijing Tongmei Xtal Technology                                        
Summary of investments                                        
Private equity ownership percentage                               0.0038%        
Beijing Boyu Semiconductor Vessel Craftwork Technology Co Ltd | Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment                                        
Summary of investments                                        
Private equity ownership percentage                               7.59%        
Beijing Boyu Semiconductor Vessel Craftwork Technology Co Ltd | Beijing Tongmei Xtal Technology                                        
Summary of investments                                        
Private equity ownership percentage                               7.59%        
Majority-Owned Subsidiaries [Member]                                        
Summary of investments                                        
Investments, consolidated method                         $ 14,211,000 $ 12,089,000            
Nanjing JinMei Gallium Co., Ltd Investment                                        
Summary of investments                                        
Investments, consolidated method                         $ 592,000 592,000            
Nanjing JinMei Gallium Co., Ltd Investment | Nanjing JinMei Gallium Co., Ltd Investment                                        
Summary of investments                                        
Percentage of ownership, consolidated method (in hundredths)                         85.50%              
ChaoYang Jin Mei Gallium Co., Ltd                                        
Summary of investments                                        
Investments, consolidated method                         $ 1,820,000 1,820,000            
ChaoYang Jin Mei Gallium Co., Ltd | ChaoYang Jin Mei Gallium Co., Ltd                                        
Summary of investments                                        
Percentage of ownership, consolidated method (in hundredths)                         85.50%              
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment                                        
Summary of investments                                        
Investments, consolidated method                         $ 1,346,000 1,346,000            
Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment | Beijing BoYu Semiconductor Vessel Craftwork Technology Co., Ltd Investment                                        
Summary of investments                                        
Percentage of ownership, consolidated method (in hundredths)                         85.50%              
ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                        
Summary of investments                                        
Investments, consolidated method                         $ 3,122,000 1,000,000            
Increase in redeemable noncontrolling interests       $ 75,000   $ 36,000                            
ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd. | ChaoYang ShuoMei High Purity Semiconductor Materials Co., Ltd.                                        
Summary of investments                                        
Percentage of ownership, consolidated method (in hundredths)                         75.00%              
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                        
Summary of investments                                        
Investments, consolidated method                         $ 7,331,000 $ 7,331,000            
Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd. | Chao Yang XinMei High Purity Semiconductor Materials Co. Ltd.                                        
Summary of investments                                        
Percentage of ownership, consolidated method (in hundredths)                         58.50%              
v3.24.0.1
Investments in Privately-held Raw Material Companies - Gain (loss) on sale and remeasurement of equity method investments (Details) - USD ($)
 1 Months Ended 12 Months Ended
May 31, 2023
Nov. 30, 2023
May 31, 2023
Dec. 31, 2023
Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]          
Fair value of the consideration received       $ 779,000  
Gain (loss) recognized on sale       (166,000)  
Fair value of the retained investment in Emeishan Jia Mei High Purity Metals Co., Ltd.       $ 551,000 $ 1,887,000
Percentage of equity interest sold       15.00%  
Emeishan Jia Mei High Purity Metals Co., Ltd Investment          
Schedule of Equity Method Investments [Line Items]          
Foreign income tax withholding       $ 48,000  
Carrying value       (252,000)  
Gain (loss) recognized on sale     $ 575,000 575,000  
Fair value of the retained investment in Emeishan Jia Mei High Purity Metals Co., Ltd.       551,000  
Carrying value of retained noncontrolling investment (10%)       (168,000)  
Gain on retained noncontrolling investment due to remeasurement (10%)       $ 383,000  
Percentage of equity interest sold 15.00%     15.00%  
Percentage of ownership, cost method 10.00%   10.00% 10.00%  
Percentage of ownership, equity method 25.00%   25.00% 10.00%  
Donghai County Dongfang High Purity Electronic Materials Co., Ltd Investment          
Schedule of Equity Method Investments [Line Items]          
Fair value of the consideration received   $ 600,000   $ 585,000  
Carrying value       (1,710,000)  
Gain (loss) recognized on sale       $ (1,125,000)  
Fair value of the retained investment in Emeishan Jia Mei High Purity Metals Co., Ltd.         $ 1,887,000
Percentage of equity interest sold   46.00%   46.00%  
Percentage of ownership, cost method   0.00%   0.00%  
Percentage of ownership, equity method   46.00%      
v3.24.0.1
Investments in Privately-held Raw Material Companies - Minority Investment Entities (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2023
Sep. 30, 2023
Jun. 30, 2023
Mar. 31, 2023
Dec. 31, 2022
Sep. 30, 2022
Jun. 30, 2022
Mar. 31, 2022
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Summarized income information of all the minority investment entities that are not consolidated and accounted for under the equity method [Abstract]                      
Net revenue $ 20,429 $ 17,366 $ 18,595 $ 19,405 $ 26,795 $ 35,183 $ 39,487 $ 39,653 $ 75,795 $ 141,118 $ 137,393
Gross profit 4,627 $ 1,866 $ 1,715 $ 5,110 8,596 $ 14,782 $ 15,435 $ 13,308 13,318 52,121 47,414
Net income                 (19,193) 18,742 16,509
Minority investment entities                      
Current assets 170,656       183,545       170,656 183,545  
Current liabilities 81,557       75,326       81,557 75,326  
Undistributed retained earnings                 8,100 9,200  
Five Minority Investments                      
Summarized income information of all the minority investment entities that are not consolidated and accounted for under the equity method [Abstract]                      
Net revenue                 32,544 48,139 35,939
Gross profit                 11,698 27,000 17,465
Operating income                 10,115 24,987 14,293
Net income                 8,681 19,104 12,560
Minority investment entities                      
Current assets 31,636       43,091       31,636 43,091  
Noncurrent assets 19,751       12,520       19,751 12,520  
Current liabilities $ 7,367       $ 10,552       7,367 10,552  
Five Minority Investments                      
Minority investment entities                      
Entity income (loss) excluding impairment                 1,900 6,000 4,400
AXT, Inc. Stockholders' Equity                      
Summarized income information of all the minority investment entities that are not consolidated and accounted for under the equity method [Abstract]                      
Net revenue                 10,033 15,031 11,424
Gross profit                 3,365 8,229 5,482
Operating income                 2,724 7,532 4,495
Net income                 $ 1,884 $ 5,957 $ 4,409
v3.24.0.1
Balance Sheets Details - Other Assets (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Components of other assets    
Equity method investments $ 12,476 $ 14,607
Value added tax receivable, long term 1,291 1,632
Other intangible assets 1,821 1,926
Deferred tax assets 1,683 2,236
Other assets 1,627 1,230
Other assets, Total $ 18,898 $ 21,631
v3.24.0.1
Balance Sheets Details - Accrued Liabilities (Details) - USD ($)
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Components of accrued liabilities      
Payable in connection with construction in progress $ 7,249,000 $ 4,135,000  
Accrued compensation and related charges 3,707,000 4,774,000  
Preferred stock dividends payable 2,901,000 2,901,000  
Accrued professional services 868,000 930,000  
Accrued product warranty 703,000 669,000 $ 743,000
Other tax payable 493,000 867,000  
Current portion of operating lease liabilities 458,000 485,000  
Advances from customers 305,000 338,000  
Other personnel-related costs 286,000 291,000  
Accrual for sales returns 39,000 112,000  
Accrued income taxes   729,000  
Other accrued liabilities 2,010,000 1,933,000  
Accrued liabilities, Total $ 19,019,000 $ 18,164,000  
v3.24.0.1
Bank Loans and Line of Credit - Schedule of Bank Loans (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2022
Dec. 31, 2023
Bank Loans and Line of Credit    
Loan Balance $ 47,078 $ 52,921
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 2.7 Percent, March 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,108
Interest Rate   2.70%
Loan Balance 2,175  
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 4.6 Percent, January 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 3,935
Interest Rate   4.60%
Loan Balance 4,059  
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 4.2 Percent, April 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,405
Interest Rate   4.20%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 2.8 Percent, March 2024 Due Date One    
Bank Loans and Line of Credit    
Loan Detail   $ 2,184
Interest Rate   2.80%
Loan Balance   $ 2,118
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 2.7 Percent, September 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 376
Interest Rate   2.70%
Loan Balance   $ 386
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 3.5 Percent, November 2024 Due Date One    
Bank Loans and Line of Credit    
Loan Detail   $ 876
Interest Rate   3.50%
Loan Balance   $ 876
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 3.5 Percent, November 2024 Due Date Two    
Bank Loans and Line of Credit    
Loan Detail   $ 1,003
Interest Rate   3.50%
Loan Balance   $ 1,003
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 3.5 Percent, January 2024 Due Date Two    
Bank Loans and Line of Credit    
Loan Detail   $ 2,911
Interest Rate   3.50%
Loan Balance   $ 2,825
Beijing Tongmei Xtal Technology | Bank of China | Bank Loan with 3.9 Percent, March 2022 Due Date Two.    
Bank Loans and Line of Credit    
Loan Detail   $ 1,848
Interest Rate   3.50%
Loan Balance   $ 1,795
Beijing Tongmei Xtal Technology | Bank of Communications | Bank Loan with 3.3 Percent January 2023 Due Date Two    
Bank Loans and Line of Credit    
Loan Detail   $ 1,450
Interest Rate   3.30%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | Bank of Communications | Bank Loan with 3.3 Percent, January 2024 Due Date Two    
Bank Loans and Line of Credit    
Loan Detail   $ 1,455
Interest Rate   3.30%
Loan Balance   $ 1,414
Beijing Tongmei Xtal Technology | Bank of Communications | Bank Loan with 3.8 Percent, May 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,380
Interest Rate   3.80%
Loan Balance   $ 1,414
Beijing Tongmei Xtal Technology | Bank of Communications | Bank Loan with 3.8 Percent, May 2024 Due Date One    
Bank Loans and Line of Credit    
Loan Detail   $ 1,373
Interest Rate   3.80%
Loan Balance   $ 1,414
Beijing Tongmei Xtal Technology | Bank of Communications | Bank Loan with 4 Percent September 2022 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 1,405
Interest Rate   3.30%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | Bank of Communications | Bank Loan with 4 Percent November 2022 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 1,405
Interest Rate   3.30%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | China Merchants Bank | Bank Loan with 4.2 Percent, December 2022 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 4,367
Interest Rate   3.70%
Loan Balance   $ 4,235
Beijing Tongmei Xtal Technology | Bank of Beijing | Bank Loan with 4.2 Percent, May 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 3,192
Interest Rate   4.20%
Loan Balance 3,292  
Beijing Tongmei Xtal Technology | Bank of Beijing | Bank Loan with 4.2 Percent One, January 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,290
Interest Rate   4.20%
Loan Balance   $ 2,220
Beijing Tongmei Xtal Technology | Bank of Beijing | Bank Loan with 3.2 Percent, May 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 3,541
Interest Rate   3.20%
Loan Balance   $ 3,626
Beijing Tongmei Xtal Technology | Bank of Beijing | Bank Loan with 3.2 Percent, February 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,380
Interest Rate   3.20%
Loan Balance   $ 1,414
Beijing Tongmei Xtal Technology | Bank of Beijing | Bank Loan with 3.0 Percent, December 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,414
Interest Rate   3.00%
Loan Balance   $ 1,414
Beijing Tongmei Xtal Technology | Industrial Bank | Bank Loan with 4.4 Percent, June 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 5,621
Interest Rate   4.40%
Loan Balance 5,798  
Beijing Tongmei Xtal Technology | Industrial Bank | Bank Loan with 4.4 Percent, September 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 2,811
Interest Rate   4.40%
Loan Balance 2,900  
Beijing Tongmei Xtal Technology | Industrial Bank | Bank Loan with 4.3 Percent, June 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,757
Interest Rate   4.30%
Loan Balance   $ 2,825
Beijing Tongmei Xtal Technology | Industrial Bank | Bank Loan with 4.3 Percent, July 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,744
Interest Rate   4.30%
Loan Balance   $ 2,825
Beijing Tongmei Xtal Technology | Industrial Bank | Bank Loan with 4.3 Percent, September 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,744
Interest Rate   4.30%
Loan Balance   $ 2,825
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.8 Percent, June 2023 Due Date One    
Bank Loans and Line of Credit    
Loan Detail   $ 1,405
Interest Rate   4.80%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.8 Percent, August 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 1,405
Interest Rate   4.80%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.8 Percent, September 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 1,405
Interest Rate   4.80%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.5 Percent, November 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,406
Interest Rate   4.50%
Loan Balance 1,450  
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.5 Percent, December 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,900
Interest Rate   4.50%
Loan Balance 2,900  
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.2 Percent, September 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,744
Interest Rate   4.20%
Loan Balance   $ 2,820
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.3 Percent, November 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,271
Interest Rate   4.30%
Loan Balance   $ 1,271
Beijing Tongmei Xtal Technology | NingBo Bank | Bank Loan with 4.3 Percent, December 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,825
Interest Rate   4.30%
Loan Balance   $ 2,825
Beijing Tongmei Xtal Technology | Industrial and Commercial Bank of China | Bank Loan with 3.2 Percent, July 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 5,621
Interest Rate   3.20%
Loan Balance 5,800  
Beijing Tongmei Xtal Technology | Industrial and Commercial Bank of China | Bank Loan with 3.3 Percent, September 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,744
Interest Rate   3.30%
Loan Balance   $ 2,825
Beijing Tongmei Xtal Technology | NanJing Bank | Bank Loan with 4.3 Percent, September 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 2,811
Interest Rate   4.30%
Loan Balance 2,899  
Beijing Tongmei Xtal Technology | NanJing Bank | Bank Loan with 4.3 Percent, November 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,265
Interest Rate   4.30%
Loan Balance $ 1,305  
Beijing Tongmei Xtal Technology | NanJing Bank | Bank Loan with 3.8 Percent, October 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 2,752
Interest Rate   3.80%
Loan Balance   $ 2,752
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | Bank of China | Bank Loan with 2.4 Percent, January 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,204
Interest Rate   2.40%
Loan Balance   $ 849
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | Bank of Communications | Bank Loan with 3.0 Percent, May 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,414
Interest Rate   3.00%
Loan Balance   $ 1,414
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | Industrial Bank    
Bank Loans and Line of Credit    
Guarantee fee (as a percent) 0.70%  
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | Industrial Bank | Bank Loan With 3.6 Percent September 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 688
Interest Rate   3.60%
Loan Balance   $ 708
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | NingBo Bank | Bank Loan with 4.8 Percent, June 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 725
Interest Rate   4.80%
Loan Balance $ 725  
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | NingBo Bank | Bank Loan with 4.8 Percent, March 2023 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 703
Interest Rate   4.80%
Loan Balance 725  
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | NingBo Bank | Bank Loan with 3.6 Percent, May 2023 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,406
Interest Rate   3.60%
Loan Balance 1,450  
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | NingBo Bank | Bank Loan with 3.3 Percent, May 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,414
Interest Rate   3.30%
Loan Balance   $ 1,414
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | Industrial and Commercial Bank of China | Bank Loan with 2.7 Percent, December 2024 Due Date    
Bank Loans and Line of Credit    
Loan Detail   $ 1,414
Interest Rate   2.70%
Loan Balance   $ 1,414
Beijing BoYu Semiconductor Vessel Craftwork Technology Co | Industrial and Commercial Bank of China | Bank Loan with 3.9 Percent, December 2022 Due Date.    
Bank Loans and Line of Credit    
Loan Detail   $ 1,450
Interest Rate   2.80%
Loan Balance $ 1,450  
v3.24.0.1
Stockholders' Equity and Stock Repurchase Program (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2015
Oct. 27, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Preferred stock, shares issued (in shares) 883,000 883,000      
Cumulative annual dividend rate (as a percent) 5.00% 5.00%      
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001      
Preferred stock, shares outstanding (in shares) 883,000 883,000      
Preferred stock, value $ 3,532,000 $ 3,532,000      
Liquidation preference over common stock (in dollars per share) $ 4 $ 4      
Stock repurchase program, authorized amount         $ 5,000,000.0
Shares repurchased (in shares) 0 0 0 908,000  
Average price of shares repurchased (in dollars per share)       $ 2.52  
Total purchase price       $ 2,300,000  
Stock repurchase program remaining authorized repurchase amount $ 2,700,000        
Preferred stock dividends payable $ 2,901,000 $ 2,901,000      
Series A Preferred Stock          
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Preferred stock, shares issued (in shares) 883,000 883,000      
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001      
Preferred stock, shares outstanding (in shares) 883,000 883,000      
Preferred stock dividends payable       $ 2,900,000  
v3.24.0.1
Stockholders' Equity and Stock Repurchase Program - Ownership Interest in Consolidated Subsidiaries (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2023
Sep. 30, 2023
Jun. 30, 2023
Mar. 31, 2023
Dec. 31, 2022
Sep. 30, 2022
Jun. 30, 2022
Mar. 31, 2022
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Stockholders' Equity and Stock Repurchase Program                      
Net income attributable to AXT, Inc. $ (3,621) $ (5,823) $ (5,089) $ (3,348) $ 1,341 $ 5,759 $ 5,546 $ 3,165 $ (17,881) $ 15,811 $ 14,575
Decrease in additional paid-in capital for:                      
Investment in subsidiary with noncontrolling interest                 (308) (937)  
Change from net income (loss) attributable to AXT, Inc., net of transfers to noncontrolling interests                 $ (18,189) $ 14,874  
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation (Details) - USD ($)
 1 Months Ended 12 Months Ended
May 31, 2021
May 31, 2019
May 31, 2015
May 31, 2013
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Employee Stock Option [Member]              
Share-based Compensation Arrangement by Share-based Payment Award              
Exercised (in shares)         4,000 172,000 507,000
Intrinsic value of options exercised         $ 7,000 $ 800,000 $ 3,700,000
1997 Stock Option Plan              
Share-based Compensation Arrangement by Share-based Payment Award              
Number of shares available for grant (in shares)         1,928,994    
2007 Equity Incentive Plan              
Share-based Compensation Arrangement by Share-based Payment Award              
Number of shares authorized for issuance (in shares)         1,300,000    
Number of additional shares authorized for issuance (in shares)       2,000,000      
2007 Equity Incentive Plan | Employee Stock Option [Member]              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         3 years    
2007 Equity Incentive Plan | Restricted stock awards | Time based vesting              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         3 years    
2007 Equity Incentive Plan | Restricted stock awards | Performance Based Vesting              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         12 months    
2007 Equity Incentive Plan | Maximum | Employee Stock Option [Member]              
Share-based Compensation Arrangement by Share-based Payment Award              
Expected term         10 years    
2015 Equity Incentive Plan              
Share-based Compensation Arrangement by Share-based Payment Award              
Number of shares authorized for issuance (in shares)     399,562        
Number of additional shares authorized for issuance (in shares) 3,600,000 1,600,000 3,000,000        
Number of shares available for grant (in shares)         1,700,000    
2015 Equity Incentive Plan | Consultant              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         1 year    
2015 Equity Incentive Plan | Employee Stock Option [Member]              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         4 years    
2015 Equity Incentive Plan | Restricted stock awards | Time based vesting              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         3 years    
2015 Equity Incentive Plan | Restricted stock awards | Performance Based Vesting              
Share-based Compensation Arrangement by Share-based Payment Award              
Vesting period         12 months    
2015 Equity Incentive Plan | Maximum | Employee Stock Option [Member]              
Share-based Compensation Arrangement by Share-based Payment Award              
Expected term         10 years    
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - Options (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Employee Stock Option [Member]        
Number of Options Outstanding        
Options outstanding, beginning of period (in shares) 1,206,000 1,378,000 1,885,000  
Exercised (in shares) 4,000 172,000 507,000  
Canceled and expired (in shares) (4,000)      
Options outstanding, end of period (in shares) 1,198,000 1,206,000 1,378,000 1,885,000
Options vested and unvested options expected to vest, net of forfeitures, end of period (in shares) 1,198,000      
Options exercisable, end of period (in shares) 1,198,000      
Weighted-average Exercise Price        
Options outstanding, beginning of period (in dollars per share) $ 5.09 $ 4.83 $ 4.42  
Exercised (in dollars per share) 2.30 3.02 3.30  
Canceled and expired (in dollars per share) 4.12      
Options outstanding, end of period (in dollars per share) 5.10 $ 5.09 $ 4.83 $ 4.42
Options vested and unvested options expected to vest, net of forfeitures (in dollars per share) 5.10      
Options exercisable, end of period (in dollars per share) $ 5.10      
Weighted average Remaining Contractual Life        
Options outstanding 4 years 1 month 2 days 5 years 29 days 5 years 7 months 6 days 6 years 2 months 1 day
Options vested and unvested options expected to vest, net of forfeitures, end of period 4 years 1 month 2 days      
Option exercisable, end of period 4 years 1 month 2 days      
Aggregate Intrinsic Value        
Options outstanding, beginning of period $ 630,000 $ 5,573,000 $ 9,713,000  
Options outstanding, end of period 14,000 $ 630,000 $ 5,573,000 $ 9,713,000
Options vested and expected to vest, end of period 14,000      
Options exercisable, end of period 14,000      
2015 Equity Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award        
Value of estimated forfeitures $ 0      
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - Options Exercise Prices (Details)
shares in Thousands
 12 Months Ended
Dec. 31, 2023
$ / shares
shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Options outstanding, shares (in shares) | shares 1,198
Weighted-average Exercise Price (in dollars per share) $ 5.10
Weighted-average Remaining Contractual Life 4 years 1 month 2 days
Options Vested and Exercisable, Shares (in shares) | shares 1,198
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 5.10
$ 2.14 - $ 2.14  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 2.14
Range of exercise price, maximum (in dollars per share) $ 2.14
Options outstanding, shares (in shares) | shares 8
Weighted-average Exercise Price (in dollars per share) $ 2.14
Weighted-average Remaining Contractual Life 3 months 29 days
Options Vested and Exercisable, Shares (in shares) | shares 8
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 2.14
$ 2.18 - $ 2.18  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 2.18
Range of exercise price, maximum (in dollars per share) $ 2.18
Options outstanding, shares (in shares) | shares 54
Weighted-average Exercise Price (in dollars per share) $ 2.18
Weighted-average Remaining Contractual Life 1 year 10 months 2 days
Options Vested and Exercisable, Shares (in shares) | shares 54
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 2.18
$ 2.47 - $2.47  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 2.47
Range of exercise price, maximum (in dollars per share) $ 2.47
Options outstanding, shares (in shares) | shares 15
Weighted-average Exercise Price (in dollars per share) $ 2.47
Weighted-average Remaining Contractual Life 10 months 2 days
Options Vested and Exercisable, Shares (in shares) | shares 15
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 2.47
$ 2.56 - $2.56  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 2.56
Range of exercise price, maximum (in dollars per share) $ 2.56
Options outstanding, shares (in shares) | shares 10
Weighted-average Exercise Price (in dollars per share) $ 2.56
Weighted-average Remaining Contractual Life 2 years 3 days
Options Vested and Exercisable, Shares (in shares) | shares 10
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 2.56
$ 3.06 - $3.06  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 3.06
Range of exercise price, maximum (in dollars per share) $ 3.06
Options outstanding, shares (in shares) | shares 330
Weighted-average Exercise Price (in dollars per share) $ 3.06
Weighted-average Remaining Contractual Life 5 years 10 months 6 days
Options Vested and Exercisable, Shares (in shares) | shares 330
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 3.06
$ 5.21 - $5.21  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 5.21
Range of exercise price, maximum (in dollars per share) $ 5.21
Options outstanding, shares (in shares) | shares 352
Weighted-average Exercise Price (in dollars per share) $ 5.21
Weighted-average Remaining Contractual Life 2 years 9 months 25 days
Options Vested and Exercisable, Shares (in shares) | shares 352
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 5.21
$ 5.77 - $5.77  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 5.77
Range of exercise price, maximum (in dollars per share) $ 5.77
Options outstanding, shares (in shares) | shares 245
Weighted-average Exercise Price (in dollars per share) $ 5.77
Weighted-average Remaining Contractual Life 4 years 10 months 6 days
Options Vested and Exercisable, Shares (in shares) | shares 245
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 5.77
$ 7.95 - $7.95  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 7.95
Range of exercise price, maximum (in dollars per share) $ 7.95
Options outstanding, shares (in shares) | shares 60
Weighted-average Exercise Price (in dollars per share) $ 7.95
Weighted-average Remaining Contractual Life 3 years 29 days
Options Vested and Exercisable, Shares (in shares) | shares 60
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 7.95
$ 9.50 - $9.50  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range  
Range of exercise price, minimum (in dollars per share) 9.50
Range of exercise price, maximum (in dollars per share) $ 9.50
Options outstanding, shares (in shares) | shares 124
Weighted-average Exercise Price (in dollars per share) $ 9.50
Weighted-average Remaining Contractual Life 3 years 9 months 25 days
Options Vested and Exercisable, Shares (in shares) | shares 124
Options Vested and Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 9.50
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - RSU (Details) - Restricted stock awards - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award      
Total fair value of restricted stock awards vested $ 2.3 $ 2.3 $ 3.8
Unamortized compensation cost related to restricted stock awards $ 4.1    
Weighted-average remaining contractual terms 1 year 6 months    
Shares      
Non-vested, beginning of period (in shares) 984 875 1,022
Granted (in shares) 692 513 274
Vested (in shares) (446) (387) (407)
Forfeited (in shares) (10) (17) (14)
Non-vested, end of period (in shares) 1,220 984 875
Weighted Average Grant Date Fair Value      
Non-vested, beginning of period (in dollars per share) $ 5.55 $ 6.26 $ 5.27
Granted (in dollars per share) 2.20 4.67 9.07
Vested (in dollars per share) 5.25 6.01 5.70
Forfeited (in dollars per share) 6.37 5.34 5.38
Non-vested, end of period (in dollars per share) $ 3.75 $ 5.55 $ 6.26
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - Performance Shares (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 12 Months Ended
Feb. 20, 2024
Mar. 15, 2023
Feb. 14, 2023
Mar. 14, 2022
Feb. 15, 2022
Feb. 17, 2021
Mar. 31, 2023
Feb. 28, 2022
Feb. 28, 2021
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Performance Shares                        
Shares                        
Non-vested, beginning of period (in shares)                   76,000 152,000  
Granted (in shares)                   13,000 74,000  
Vested (in shares)                   (38,000) (76,000)  
Forfeited (in shares)                   (13,000) (74,000)  
Non-vested, end of period (in shares)                   38,000 76,000 152,000
Weighted Average Grant Date Fair Value                        
Non-vested, beginning of period (in dollars per share)                   $ 15.37 $ 15.37  
Granted (in dollars per share)                   3.71 7.83  
Vested (in dollars per share)                   15.37 15.37  
Forfeited (in dollars per share)                   3.71 7.83  
Non-vested, end of period (in dollars per share)                   $ 15.37 $ 15.37 $ 15.37
Weighted-average grant date fair value of stock options granted (in dollars per share)             $ 3.71 $ 7.83 $ 15.37      
Percentage of performance target cap of award 100.00% 100.00%                    
Percentage of year-over-year annual revenue growth rate     2.70% 44.00%                
Shares eligible to vest 0   0                  
Percentage of targeted financial performance                   150.00%    
Unrecognized compensation expense related to restricted stock awards                   $ 0.1    
Weighted-average remaining contractual terms                   10 months 6 days    
Performance Shares | Minimum | Scenario Performance Financial Metric Less Than 50%                        
Weighted Average Grant Date Fair Value                        
Percentage of targeted financial performance         50.00%              
Performance Shares | Minimum | Scenario Performance Financial Metric is Between 50% to 200%                        
Weighted Average Grant Date Fair Value                        
Percentage of targeted financial performance         50.00%              
Performance Shares | Maximum | Scenario Performance Financial Metric is Between 50% to 200%                        
Weighted Average Grant Date Fair Value                        
Percentage of targeted financial performance         200.00%              
Performance Shares | Maximum | Scenario Performance Financial Metric Greater Than 200%                        
Weighted Average Grant Date Fair Value                        
Percentage of targeted financial performance         200.00%              
Performance Shares | First Anniversary                        
Shares                        
Vested (in shares)                   0    
Weighted Average Grant Date Fair Value                        
Vesting period                   4 years    
Performance Shares | Chief Executive Officer                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period 223,590 223,590       113,130            
Performance Shares | Chief Executive Officer | Scenario Performance Minimum Financial Metric                        
Weighted Average Grant Date Fair Value                        
Share options vested in period 223,590 223,590                    
Performance Shares | Chief Executive Officer | Scenario Performance Financial Metric Less Than 50%                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period         114,320              
Performance Shares | Chief Executive Officer | Scenario Performance Financial Metric is Between 50% to 200%                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period         114,320              
Performance Shares | Chief Executive Officer | Scenario Performance Financial Metric Greater Than 200%                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period         114,320              
Performance Shares | Chief Financial Officer                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period 77,600 77,600       38,475            
Performance Shares | Chief Financial Officer | Scenario Performance Minimum Financial Metric                        
Weighted Average Grant Date Fair Value                        
Share options vested in period 77,600 77,600                    
Performance Shares | Chief Financial Officer | Scenario Performance Financial Metric Less Than 50%                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period         32,100              
Performance Shares | Chief Financial Officer | Scenario Performance Financial Metric is Between 50% to 200%                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period         32,100              
Performance Shares | Chief Financial Officer | Scenario Performance Financial Metric Greater Than 200%                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period         32,100              
Employee Stock Option [Member]                        
Weighted Average Grant Date Fair Value                        
Stock options grants in period                   0 0 0
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - Common Stock (Details)
shares in Thousands
Dec. 31, 2023
shares
Share-based Compensation Arrangement by Share-based Payment Award  
Common stock reserved for future issuance 4,198
2015 Equity Incentive Plan  
Share-based Compensation Arrangement by Share-based Payment Award  
Common stock reserved for future issuance 1,743
Employee Stock Option [Member]  
Share-based Compensation Arrangement by Share-based Payment Award  
Common stock reserved for future issuance 1,198
Restricted stock awards  
Share-based Compensation Arrangement by Share-based Payment Award  
Common stock reserved for future issuance 1,257
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - Stock-Based Compensation (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Employee Service Share-based Compensation, Allocation of Recognized Period Costs      
Net effect on net income (loss) $ 3,540 $ 4,006 $ 4,519
Effect on basic net income (loss) per share $ 0.08 $ 0.10 $ 0.11
Effect on diluted net income (loss) per share $ 0.08 $ 0.09 $ 0.11
Cost of revenue      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs      
Net effect on net income (loss) $ 414 $ 379 $ 368
Selling, general and administrative      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs      
Net effect on net income (loss) 2,502 2,947 3,514
Research and development      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs      
Net effect on net income (loss) $ 624 $ 680 $ 637
v3.24.0.1
Employee Benefit Plans and Stock-based Compensation - Assumptions (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Weighted-average assumptions      
Expected dividend (in hundredths) 0.00% 0.00% 0.00%
Retirement Savings Plan      
Period after which all full time employees are eligible to participate in the savings plan 90 days    
Contributions to the retirement savings plans $ 186,000 $ 191,000 $ 208,000
Maximum      
Retirement Savings Plan      
Maximum percentage of employer matching contribution if employees contribute at least 6% of base pay (in hundredths) 4.00%    
Minimum      
Retirement Savings Plan      
Minimum percentage of employee contribution to get 4% of employer's contribution (in hundredths) 6.00%    
v3.24.0.1
Guarantees (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Product Warranty    
Period of warranty 12 months  
Change in warranty accrual    
Beginning accrued product warranty $ 669,000 $ 743,000
Accruals for warranties issued 794,000 1,024,000
Adjustments related to pre-existing warranties including expirations and changes in estimates (159,000) (286,000)
Cost of warranty repair (601,000) (812,000)
Ending accrued product warranty $ 703,000 $ 669,000
v3.24.0.1
Income Taxes (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Operating Loss Carryforwards      
Income (loss) before provision for income taxes $ (19,033,000) $ 20,927,000 $ 17,602,000
Current:      
Federal (317,000) 848,000 223,000
State 41,000 34,000 91,000
Foreign (62,000) 918,000 3,119,000
Total current (338,000) 1,800,000 3,433,000
Deferred:      
Federal (9,000) (591,000) (188,000)
State (7,000) (4,000) (1,000)
Foreign 514,000 980,000 (2,151,000)
Total deferred 498,000 385,000 (2,340,000)
Total provision for income taxes $ 160,000 $ 2,185,000 $ 1,093,000
Reconciliation of effective income tax rates and U.S. statutory federal income tax rate      
Statutory federal income tax rate (as a percent) 21.00% 21.00% 21.00%
State income taxes, net of federal tax benefits (as a percent) (0.60%) 0.10% 0.40%
Valuation allowance (as a percent) (25.70%) (19.30%) (25.40%)
Stock-based compensation (as a percent) (1.70%) 0.70% (3.20%)
Foreign tax rate differential (as a percent) 6.10% (2.60%) (8.60%)
Foreign tax incentives (as a percent) 0.10% (3.50%) (3.20%)
Foreign income inclusion (as a percent)   18.90% 10.40%
Gain from sale of IP     16.90%
Tax effect in equity method loss or gain from unconsolidated affiliates (as a percent) 0.40% (3.00%) (2.60%)
Others (as a percent) (0.40%) (1.80%) 0.50%
Effective tax rate (as a percent) (0.80%) 10.50% 6.20%
Deferred tax assets:      
Net operating loss carryforwards $ 14,362,000 $ 9,571,000  
Accruals, reserves and other 4,349,000 4,053,000  
Credit carryforwards 325,000 206,000  
Operating lease liability 206,000 60,000  
Gross deferred tax assets 19,242,000 13,890,000  
Valuation allowance (17,462,000) (11,885,000)  
Total deferred tax assets 1,780,000 2,005,000  
Deferred tax liabilities:      
Operating lease right-of-use assets (323,000) (50,000)  
Total net deferred tax assets (included in other assets) 1,457,000 1,955,000  
Increase (decrease) in valuation allowance $ 5,600,000 (3,500,000)  
Realized benefits of tax rate reduction (as a percent) 10.00%    
Unrecognized tax benefit would favorably impact the effective tax rate in future periods if recognized $ 1,100,000 1,100,000  
Domestic Tax Authority      
Deferred tax liabilities:      
Operating loss carryforwards 40,200,000    
State      
Deferred tax liabilities:      
Operating loss carryforwards $ 115,000    
Foreign Tax Authority      
Deferred tax liabilities:      
EIT income tax rate (as a percent) 25.00%    
Preferential tax rate (as a percent) 15.00%    
Benefit from foreign tax rate $ 47,000 $ 900,000 $ 1,000,000.0
v3.24.0.1
Net Income (Loss) per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2023
Sep. 30, 2023
Jun. 30, 2023
Mar. 31, 2023
Dec. 31, 2022
Sep. 30, 2022
Jun. 30, 2022
Mar. 31, 2022
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Numerator:                      
Net income attributable to AXT, Inc. $ (3,621) $ (5,823) $ (5,089) $ (3,348) $ 1,341 $ 5,759 $ 5,546 $ 3,165 $ (17,881) $ 15,811 $ 14,575
Less: Preferred stock dividends                 (177) (177) (177)
Net income (loss) available to common stockholders                 $ (18,058) $ 15,634 $ 14,398
Denominator:                      
Denominator for basic net income (loss) per share - weighted-average common shares                 42,643 42,104 41,367
Effect of dilutive securities:                      
Denominator for dilutive net income (loss) per common shares                 42,643 42,715 42,720
Basic net income per share:                      
Basic $ (0.09) $ (0.14) $ (0.12) $ (0.08) $ 0.03 $ 0.14 $ 0.13 $ 0.07 $ (0.42) $ 0.37 $ 0.35
Diluted net income per share:                      
Diluted $ (0.09) $ (0.14) $ (0.12) $ (0.08) $ 0.03 $ 0.13 $ 0.13 $ 0.07 $ (0.42) $ 0.37 $ 0.34
Common stock options                      
Effect of dilutive securities:                      
Effect of dilutive securities (in shares)                   333 803
Weighted-average shares:                      
Securities excluded from diluted net income (loss) per share as the impact is anti-dilutive (in shares)                 1,198 220 21
Restricted stock awards                      
Effect of dilutive securities:                      
Effect of dilutive securities (in shares)                   278 550
Weighted-average shares:                      
Securities excluded from diluted net income (loss) per share as the impact is anti-dilutive (in shares)                 1,258 291 118
v3.24.0.1
Segment Information and Foreign Operations - Product Information (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Revenue by product type      
Revenue $ 75,795 $ 141,118 $ 137,393
Substrates      
Revenue by product type      
Revenue 47,466 111,094 103,026
Raw materials and others      
Revenue by product type      
Revenue $ 28,329 $ 30,024 $ 34,367
v3.24.0.1
Segment Information and Foreign Operations - Segment and Geographical Information (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
USD ($)
segment
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Segment Information and Foreign Operations      
Number of operating segments | segment 1    
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue $ 75,795 $ 141,118 $ 137,393
Long-lived assets by geographic region, net of depreciation:      
Long-lived assets 169,147 162,778  
China      
Long-lived assets by geographic region, net of depreciation:      
Long-lived assets 167,516 162,432  
North America (primarily the United States)      
Long-lived assets by geographic region, net of depreciation:      
Long-lived assets 1,631 346  
Reportable Geographical Components      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue 75,795 141,118 137,393
Reportable Geographical Components | China      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue 39,778 55,414 67,394
Reportable Geographical Components | Taiwan      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue 8,651 28,780 16,841
Reportable Geographical Components | Japan      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue 4,641 11,724 10,112
Reportable Geographical Components | Asia Pacific (excluding China, Taiwan and Japan)      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue 3,814 4,188 7,540
Reportable Geographical Components | Europe (primarily Germany)      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue 12,315 20,592 23,069
Reportable Geographical Components | North America (primarily the United States)      
Net revenues reported for products shipped to customers in corresponding geographic region      
Revenue $ 6,596 $ 20,420 $ 12,437
v3.24.0.1
Other income (expense), net (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Other income (expense), net      
Foreign exchange gain (loss) $ 169,000 $ 1,573,000 $ (434,000)
Income from local China government subsidy 2,557,000 1,710,000 1,125,000
Other income (expense) (547,000) 204,000 (182,000)
Total other income, net $ 2,179,000 $ 3,487,000 $ 509,000
v3.24.0.1
Commitments and Contingencies (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
USD ($)
ft²
Sep. 30, 2023
May 31, 2020
Leases      
Area of leased property (in square feet) | ft² 19,467    
Operating lease, extension term   5 years 3 years
Variable lease payments $ 0    
Cross License Agreement      
Leases      
Term of agreement 10 years    
Dingxing      
Leases      
Total investment agreement value $ 90,000    
Kazuo      
Leases      
Total investment agreement value 15,000    
Kazuo | Beijing BoYu Semiconductor Vessel Craftwork Technology Co      
Leases      
Total investment agreement value $ 8,000    
v3.24.0.1
Commitments and Contingencies - Maturities of Operating Lease Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Future minimum lease payments    
2024 $ 591  
2025 604  
2026 618  
2027 633  
2028 614  
Thereafter 153  
Total minimum lease payments 3,213  
Less: Interest (404)  
Present value of lease obligations 2,809  
Less: Current portion, included in accrued liabilities (458) $ (485)
Long-term portion of lease obligations $ 2,351 $ 1,322
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] Accrued Liabilities, Current Accrued Liabilities, Current
v3.24.0.1
Commitments and Contingencies - Weighted-Average Remaining Lease Term and Discount Rate (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Leases    
Weighted-average remaining lease term (years) 5 years 2 months 19 days 5 years 10 months 20 days
Weighted-average discount rate 5.14% 4.61%
Cash paid for amounts included in the measurement of lease liabilities:    
Operating cash flows from operating leases $ 578 $ 574
v3.24.0.1
Commitments and Contingencies - Components of Lease Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Lease expense    
Operating lease $ 548 $ 530
Short-term lease expense 143 137
Total $ 691 $ 667
v3.24.0.1
Unaudited Quarterly Consolidated Financial Data (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2023
Sep. 30, 2023
Jun. 30, 2023
Mar. 31, 2023
Dec. 31, 2022
Sep. 30, 2022
Jun. 30, 2022
Mar. 31, 2022
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Unaudited Quarterly Consolidated Financial Data                      
Revenue $ 20,429 $ 17,366 $ 18,595 $ 19,405 $ 26,795 $ 35,183 $ 39,487 $ 39,653 $ 75,795 $ 141,118 $ 137,393
Gross profit 4,627 1,866 1,715 5,110 8,596 14,782 15,435 13,308 13,318 52,121 47,414
Net income attributable to AXT, Inc. $ (3,621) $ (5,823) $ (5,089) $ (3,348) $ 1,341 $ 5,759 $ 5,546 $ 3,165 $ (17,881) $ 15,811 $ 14,575
Net income (loss) attributable to AXT, Inc. per share, basic (in dollar per share) $ (0.09) $ (0.14) $ (0.12) $ (0.08) $ 0.03 $ 0.14 $ 0.13 $ 0.07 $ (0.42) $ 0.37 $ 0.35
Net income (loss) attributable to AXT, Inc. per share, diluted (in dollar per share) $ (0.09) $ (0.14) $ (0.12) $ (0.08) $ 0.03 $ 0.13 $ 0.13 $ 0.07 $ (0.42) $ 0.37 $ 0.34
v3.24.0.1
Redeemable Noncontrolling Interests (Details) - Beijing Tongmei Xtal Technology - USD ($)
$ in Millions
 1 Months Ended 12 Months Ended
Jan. 25, 2021
Jan. 31, 2021
Dec. 31, 2022
Dec. 31, 2020
Dec. 31, 2023
Noncontrolling Interest          
Increase in redeemable noncontrolling interests   $ 1.5   $ 48.1  
Redeemable noncontrolling interests ownership percentage       7.06%  
Investments, government approved $ 49.0        
Percentage of equity issued on conversion of noncontrolling interests 7.28%   14.50%    
Redemption value         $ 49.0
v3.24.0.1
Redeemable Noncontrolling Interests - Components of the Change in Redeemable Noncontrolling Interests (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Redeemable Noncontrolling Interests    
Redeemable noncontrolling interests beginning balance $ 44,846 $ 50,385
Investment in subsidiary with redeemable noncontrolling interest 155 471
Equity issuance costs incurred (880) (2,699)
Stock-based compensation attributable to redeemable noncontrolling interests 52 (36)
Net loss attributable to redeemable noncontrolling interests (920) 1,598
Effect of foreign currency translation on redeemable noncontrolling interests (1,260) (3,962)
Effect of foreign currency translation attributable to redeemable noncontrolling interests (330) (911)
Redeemable noncontrolling interests ending balance $ 41,663 $ 44,846
v3.24.0.1
Subsequent Events (Details) - Subsequent Events - USD ($)
 1 Months Ended
Mar. 31, 2024
Feb. 29, 2024
Jan. 31, 2024
Subsidies From Chinese Government      
Subsequent Event      
Proceeds from grant $ 715,000 $ 715,000 $ 715,000
Secured debt      
Subsequent Event      
Proceeds from issuance of secured debt   2,800,000 2,800,000
Secured debt      
Subsequent Event      
Repayments of loan   14,500,000 14,500,000
Unsecured Debt      
Subsequent Event      
Proceeds from issuance of unsecured debt   5,100,000 $ 5,100,000
Line of Credit      
Subsequent Event      
Line of credit, term     5 years
Interest Rate     6.50%
Maximum borrowing capacity     $ 9,900,000
Borrowings     5,900,000
Bank loan      
Subsequent Event      
Proceeds from bank loan   $ 7,900,000 $ 7,900,000
Line of credit, term   1 year 1 year
Maximum | Bank loan      
Subsequent Event      
Interest rate   4.30% 4.30%
Minimum | Bank loan      
Subsequent Event      
Interest rate   3.00% 3.00%
v3.24.0.1
Pay vs Performance Disclosure - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2023
Sep. 30, 2023
Jun. 30, 2023
Mar. 31, 2023
Dec. 31, 2022
Sep. 30, 2022
Jun. 30, 2022
Mar. 31, 2022
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Pay vs Performance Disclosure                      
Net Income (Loss) $ (3,621) $ (5,823) $ (5,089) $ (3,348) $ 1,341 $ 5,759 $ 5,546 $ 3,165 $ (17,881) $ 15,811 $ 14,575
v3.24.0.1
Insider Trading Arrangements
 3 Months Ended
Dec. 31, 2023
Trading Arrangements, by Individual  
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false