A Resonant Pressure Microsensor Optimized by DETF Resonators

This paper presents a resonant pressure sensor with higher Q-factors and modal stability compared with traditional single beam micro sensor. A pair of resonators based on DETF structure were positioned on the central and side area with intrinsic frequencies to sense pressure applied to the diaphragm. FEM simulation was conducted and device fabrication was realized. The Q-factors of the resonators working in the out of phase state were more stable and higher than working in the in phase state, with a maximum difference of more than 6 times compared to the in plane state, reaching 19456 and 3118 respectively. Close-loop results show that the maximum fitting pressure error is -24.34 Pa (0.014% FS) under pressure from 0 kPa to 170 kPa and temperature from -40 degrees C to 85 degrees C, which indicate the micro sensors have high accuracy and sensitivity.