Vertically integrated CMOS-MEMS capacitive humidity sensor and a resistive temperature detector for environment application

摘要

This study demonstrates the vertically integrated environment sensor with a capacitive relative humidity sensor (RH-sensor) and a resistive temperature detector (RTD) using the TSMC 0.18μm 1P6M CMOS process. Features of this study are: (1) multiple sensing units could be vertically implemented and integrated in one chip; (2) fast response humidity sensor is realized based on fence-shaped capacitor (supported by oxide pillars) with polyimide (PI) filler; (3) simple post-CMOS processes include metal wet etching and pneumatic dispensing of PI. Measurement results indicate the RH sensor with sensitivity of 0.051%/%RH and response time of 16s; and temperature coefficient of resistance (TCR) of RTD is 0.28%/°C.