Design and simulation of low pressure piezoresistive MEMS sensor using analytical models

Abstract

Pressure micro sensors are designed to operate in linear range and presently the most widely used devices are MEMS sensors and have gained popularity in biomedical, automotive and avionics Industries. In present work a low pressure square diaphragm piezoresistive MEMS sensor of diaphragm length 1000 m and thickness 10 m respectively has been designed using the available analytical models after optimizing it for achieving close matching with finite element method (FEM) calculations. The designed sensor has been characterized through FEM simulation using MEMS CAD software tools and the analytical and simulation results have been found to be in good agreement. Also, the finite element method simulation has been used to calculate maximum stress location which is useful for placement of piezoresistive sensing element at high stress region necessary to get maximum output. The analytical and simulation results show that the designed sensor has full scale output (FSO) of 61.7 mV/V and is linear in its operating range of 50 kPa pressure. This work may be potentially useful for piezoresistive pressure sensor designers and researchers. © 2012 IEEE.