Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

Document and Entity Information - USD ($)
12 Months Ended
Sep. 30, 2022
Sep. 30, 2021
Nov. 23, 2022
Mar. 31, 2022
Cover [Abstract]        
Document Type 10-K      
Amendment Flag false      
Document Period End Date Sep. 30, 2022      
Document Fiscal Year Focus 2022      
Document Fiscal Period Focus FY      
Entity Registrant Name AMTECH SYSTEMS, INC.      
Entity Central Index Key 0000720500      
Current Fiscal Year End Date --09-30      
Entity Filer Category Non-accelerated Filer      
Entity Small Business true      
Entity Emerging Growth Company false      
Entity Voluntary Filers No      
Entity Well-known Seasoned Issuer No      
Entity Public Float       $ 113,239,072
Entity Common Stock, Shares Outstanding     14,000,154  
Entity Current Reporting Status Yes      
Entity Shell Company false      
Entity File Number 0-11412      
Entity Tax Identification Number 86-0411215      
Entity Address, Address Line One 131 South Clark Drive      
Entity Address, City or Town Tempe      
Entity Address, State or Province AZ      
Entity Address, Postal Zip Code 85288      
City Area Code 480      
Local Phone Number 967-5146      
Entity Interactive Data Current Yes      
Title of 12(b) Security Common Stock, par value $0.01 per share      
Trading Symbol ASYS      
Security Exchange Name NASDAQ      
Entity Incorporation, State or Country Code AZ      
Document Annual Report true      
Document Transition Report false      
Documents Incorporated by Reference

Portions of the Definitive Proxy Statement related to the registrant’s 2023 Annual Meeting of Shareholders, which Proxy Statement will be filed under the Securities Exchange Act of 1934, as amended, within 120 days of the end of the registrant’s fiscal year ended September 30, 2022, are incorporated by reference into Items 10-14 of Part III of this Form 10-K.

ICFR Auditor Attestation Flag false      
Auditor Firm ID 248 199    
Auditor Location Phoenix, Arizona Phoenix, Arizona