Spreadtrum Communications has placed 40nm chip orders with United Microelectronics' (UMC) recently-opened 12-inch wafer fab in Xiamen, China, according to industry sources.

UMC entered risk production for a Spreadtrum chip on a 40nm process at its Xiamen fab at the end of July, and received validation for the product at the end of September. The foundry has begun producing 40nm chips in small volume for Spreadtrum at the fab, with shipments kicking off in November, the sources indicated.

Monthly production capacity at UMC's Xiamen fab is set to reach 3,000 wafers by the end of 2016, and will expand to 25,000 units in 2018 for its first phase of expansion, the sources said.

UMC is already a close partner of Spreadtrum, which has placed 40nm and 28nm chip orders with the foundry's 12-inch fab in Taiwan, the sources noted. Spreadtrum is among UMC's major clients, which include Qualcomm and MediaTek.

Earlier in November 2016, UMC held an opening ceremony for a new 12-inch wafer fab in Xiamen. Dubbed Fab 12X, the fab is part of a 3-way joint venture foundry, named United Semi, between UMC, Xiamen Municipal Government and Fujian Electronics and Information Group. United Semi offers 55nm and 40nm process technologies, and has its target monthly capacity set at 50,000 wafers.

UMC is looking to have its Xiamen fab make 28nm chips legitimately in the second half of 2017, when its Taiwan fabs will have to be capable of producing chips using more advanced 14nm FinFET process technology, the sources believe. Bitcoin mining company BitFury will reportedly be the first customer adopting UMC's 14nm technology.