Analytical Model for Pressure Sensing with Capacitive Micromachined Ultrasonic Transducer

Capacitive micromachined ultrasonic transducer (CMUT) is a proven physical sensor for its high sensitivity, low power consumption, and ease of integration with CMOS circuits. This paper explores the potential of CMUTs in pressure sensing. Through electromechanical coupling analysis, we established a analytical model to describe the frequency response under the combined loadings of pressure and electrostatic force. The CMUT exhibited high linearity, and the analyzed pressure sensitivity was as high as 4.06Hz/Pa, the accuracy of which was examined by finite element simulation. The maximum deviation of the two simulations was 0.7%, verifying the effectiveness of the analytical model.