Semiconductor on polymer substrate

Abstract

Semiconductor On Polymer (SOP) is a flexible ultra-thin substrate that can be used as the starting material for CMOS, MEMS or Complex Interconnects such as an interposer. The described process results in a flexible SOP device with open bond pads. After deposition of a liquid polymer onto a semiconductor substrate, the polymer is converted to a solid, creating a new substrate that is temporarily bonded to a carrier wafer. The semiconductor layer is then etched to be ultra-thin and highly uniform, specifically, a single crystalline silicon layer. Following fabrication of devices and interconnects on the polymer substrate, the ultra thin wafer is released from the carrier wafer in substrate form to be used whole or tiled for subsequent assembly. Among other advantages, the flexible format of the SOP substrate enables low resistance 3-D interconnects, and provides for a significant increase in performance due to a reduction in parasitic capacitance.