A micromachined resonant pressure sensor with DETFs resonator and differential structure

A novel micromachined resonant pressure sensor designed with DETFs (double-ended tuning forks) resonant beam and differential structure was put forward in this paper. Three groups of DETFs resonant beams form the differential structure to achieve the better sensitivity and make the sensor free of the environment changes. Four beams with the same size compose the DETFs to improve the Q-factor of the sensor. The structural parameters were optimized through FEM (finite elements method) analysis. The boron diffused silicon processes was used to realize the pressure sensor on single silicon wafer to simplify the fabrication process. Experiments show that the Q-factors of all groups of resonant beams are beyond 10000 and the sensitivity of the sensor is about 353 Hz/kPa when pressure varying from 0 to 100 kPa.