A Resonant High-Pressure Sensor with High Strength Design

This paper presents a resonant high-pressure sensor with measurement range of 50 MPa based on high strength design which can minimize the stresses induced by surrounding pressure. Pressure under measurement bends the pressure sensitive diaphragm, producing frequency shifts of the resonators. The sensor structures were optimized by using the finite element analysis to extend the pressure sensitive range, especially in structure strength and sensitivities, and were fabricated by bulk-micromachining processes. Experimental results showed that the pressure sensitivity of the resonators was 0.107 Hz/kPa (resonator I) and -0.045 Hz/kPa (resonator II), with a differential temperature sensitivity of -0.409 Hz/°C.