Polyimide sacrificial layer for SOI SG-MOSFET pressure sensor

This paper reports on the fabrication and electrical characterization of a novel pressure sensor based on a suspended-gate MOSFET (SG-MOSFET) using a new polyimide process. The device is composed of a SG-MOSFET built on a thin SOI membrane released by a backside silicon wafer etching. The membrane deflection induced by the backside-applied pressure (up to 250 kPa) is detected by the variation of the MOSFET drain current. Device behavior simulations and optimized fabrication process flow are presented as well as the first electrical characterization of the SG-MOSFET.