Design and optimization of a mems based piezoresistive pressure sensor for flash flood level measurement

Abstract

This paper is focused on designing and optimization of a Micro Electro Mechanical System (MEMS) based piezoresistive type pressure sensor to enhance the sensitivity by optimally utilizing the maximum available Silicon wafer cell volume of 3mmX3mmX400pm and a fixed thickness of IOpm due to fabrication constrains. Here an analysis is carried out by varying the dimensions of two different diaphragm geometries, namely conventional square type diaphragm and cross-sectional beam type diaphragm. The analysis is done using finite element method (FEM) technique in ANSYS software and by comparing the results, the better diaphragm type is chosen for the required pressure range of the application for flash flood level measurement. The results show that for some pressure ranges the cross-sectional beam type diaphragm delivers a much better sensitivity than the conventional square type diaphragm.