The influence of temperature on the pressure sensitivity of surface acoustic wave pressure sensor

Abstract

This paper illustrates the effect of temperature on AlN-based surface acoustic wave (SAW) pressure sensor. The resonance frequency of the SAW pressure sensor at different temperatures and pressures have been simulated and extracted in the COMSOL Multiphysics software, and the pressure coefficient of frequency (PCF) was obtained as 157.31 ppm/MPa through the linear fitting. The PCF at room temperature was experimentally measured to be 101.46 ppm/MPa in the pressure range of 0 MPa to 2 MPa. In addition, the effect of temperature on PCF has been investigated by simulation analysis and it was found that PCF increases with temperature due to thermal mismatch between different films rather than the effect of temperature on the Young's modulus. The experimental findings have proved the increase of PCF with temperature and the obtained data are found in good agreement with simulation results.