Analysis and validation of thermal and packaging effects of a piezoresistive pressure sensor

In this study, a packaged silicon base piezoresistive pressure sensor with thermal stress buffer is designed, fabricated, and studied. A finite element method (FEM) is adopted for designing and optimizing the sensor performance. Thermal and pressure loading on the sensor is applied to make a comparison between experimental and simulation results. Furthermore, a method that transforms simulation stress data into output voltage is proposed in this study, and the results indicate that the experimental result coincides with the simulation data. In order to achieve better sensor performance, a parametric analysis is performed to evaluate the system sensitivity, as well as thermal and packaging effects of the pressure sensor. The design parameters of the pressure sensor include membrane size, sensor chip size, glass thickness, adhesive layer thickness, PCB thickness/material, etc. The findings show that proper selection of the sensor structure and material not only enhances the sensor sensitivity but also reduces the thermal effects as well as the packaging influence.