High-Pressure Silicon Resonant Microsensor Based on Microbeam Arrays

Distinct from conventional pressure sensitive diaphragm sensors, this study presents a novel design of a high-pressure silicon resonant pressure microsensor employing a microbeam array. This sensor utilizes microbeam arrays to regulate the axial stress of resonators, allowing two distinct resonant beams to experience tensile and compressive stress respectively when the sensor as a whole is subjected to pressure. This configuration enables accurate pressure measurements within the range of 0.1 MPa to 100 MPa. Resonator I exhibits a sensitivity of -122.45 Hz/MPa Resonator II shows a sensitivity of 64.80Hz/MPa and the differential output at 20°C is 187.25Hz/MPa ppm/MPa). Performance characterization of the fabricated sensor was conducted within open-loop and closed-loop systems. Finally, the microsensor exhibited high accuracy in closed-loop testing, with a maximum fitting error of 1.49kPa (0.03% FS) within a range of 0–5 MPa and -20 to 60°C.