Siliconware Precision Industries (SPIL) has won the bid to take over the idle 12-inch fab of ProMOS Technologies for NT$6.4 billion (US$213.62 million). SPIL will use the fab to develop its high-end 2.5D/3D IC testing/packaging technologies.

Taiwan Semiconductor Manufacturing Company (TSMC) and Micron Technology reportedly also participated in the bidding, but the two firms have no urgent need to buy the idle fab at this moment, according to industry sources.

TSMC has its own standards for building cleanrooms, while Micron still can ramp up its capacity using the new plants available at Inotera Memories or Rexchip Electronics, the sources added.

ProMOS sold the bulk of the equipment from the fab to Globalfoundries in a previous bidding held in 2013.