摘要
In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent accuracy.The composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element simulation.An all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency output.The microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 MPa.The differential output had an outstanding stability within±0.02 Hz under constant temperature and pressure.Thus,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.
基金
supported in part by the National Key R&D Program of China under Grant 2022YFB3207300
in part by the National Science Fund for Distinguished Young Scholars under Grant 61825107
in part by the National Natural Science Foundation of China under Grant 62301536
Grant 62121003,Grant 62201549,and Grant U1930206
in part by the Youth Innovation Promotion Association CAS under Grant 2023134 and Grant 2022121
in part by the Instrument Research and Development of CAS under Grant GJJSTD20210004.