Improved Analytical Model for Load – Deflection Performance of SOI Pressure Sensor and Comparison with Simulation Results

Abstract: Silicon-on-Insulator (SOI) pressure sensor diaphragm is a composite structure of the buried oxide and the SOI layer. This paper brings out the inadequacy of the existing analytical model in describing the deflection response of SOI square diaphragms and focuses on development of new improved analytical model that describes the load- deflection performance of SOI composite diaphragm. This improved model is able to predict the small scale as well as large scale deflection accurately when compared with deflection obtained by IntelliSuite FEA. Further, the new model has been demonstrated that the existing analytical model overestimates the deflection and hence inadequate for application to SOI pressure sensors.

Keywords: Silicon-on-insulator; Micro electro mechanical systems; Finite element analysis; Pressure sensor; IntelliSuite; Improved analytical model