The U.S. Commerce Department is investigating whether SMIC illegally obtained U.S. tools to manufacture Kirin 9000S chips

The U.S. Department of Commerce is investigating whether SMIC illegally obtained U.S. tools to manufacture Kirin 9000S chips. The chipmaker may have violated export rules, but the situation is still being evaluated, according to Alan Estevez, a senior official at the department.

The announcement follows congressional hearings earlier this week and reports that the Biden administration is considering adding four more chipmakers to the sanctions entity list, including Semiconductor Manufacturing International Corporation (SMIC), Huawei's 7nm FinFET SoC supplier.

Huawei's Mate60Pro and several other Mate and nova12 phones use the Kirin 9000S chip, which is produced using SMIC's existing manufacturing facilities despite the U.S. ban. The company has repeatedly declined to make official comments on the matter.

Reuters writes that the phone is seen as a symbol of the renaissance of China's chip industry, despite Washington's ongoing efforts to weaken Chinese semiconductor companies.

Reuters quoted Estevez as saying that while they could not talk about any investigations that may or may not be ongoing, their team "certainly shares concerns" about SMIC's use of U.S. tools to make 5G-enabled chipsets.