Design and Characterization of a CMOS MEMS Capacitive Squeeze-Film Pressure Sensor

Abstract

A capacitive pressure sensor operated based on the elastic squeeze-film damping effect is implemented, for the first time, in a CMOS process to provide sensor integration and sensitivity improvement. Sensor fabrication is simplified as a squeeze-film pressure sensor does not require a sealed membrane as in conventional sensors; in addition, sensitivity is significantly enhanced with the small gap achieved between capacitive plates. The sensor with a resonant plate size of 200×200 μm ² demonstrates a sensitivity of 793 Hz/kPa.