The state-linked Institute of Microelectronics (IME) was first thrust into the spotlight in February when the London-based Financial Times cast doubt on the apparent suicide of one of its former researchers -- US electronics engineer Shane Todd, who was found hanged in his Singapore flat in June 2012.
It said his family suspected he was murdered because of his work on a joint IME project with Huawei Technologies involving gallium nitride, a semiconductor material with military and commercial applications.
"The US officials who came for the audit were satisfied with the audit," the ministry said in the short statement.
Huawei -- accused by US officials of involvement in espionage -- and IME said they had only held preliminary talks on a potential project with commercial applications, but had not gone further.
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A state coroner subsequently ruled in July that 31-year- old Todd committed suicide during a bout of depression, debunking his family's conspiracy theory.
The US government said in July the two-week enquiry was "comprehensive, fair and transparent".
The foreign ministry said the audit had been offered to US officials by IME on a "voluntary basis".
It said the offer had been conveyed to Secretary of State John Kerry by Foreign Minister K Shanmugam during a visit to Washington in March.
The offer was made "in the spirit of cooperation and openness to satisfy the US that allegations of illegal transfers of US technology from IME to the Chinese company Huawei were completely untrue and without basis", the ministry said.