Modeling of capacitance and sensitivity of a MEMS pressure sensor

Abstract

In this paper modeling of capacitance and sensitivity for MEMS capacitive pressure sensor is presented. In capacitive sensor the sensitivity is proportional to deflection and capacitance changes versus pressure. Therefore first the diaphragm displacement, capacitance and sensitivity of sensor with square diaphragm have been modeled and then simulated using finite element method (FEM). It can be seen that the analytical results are very agreement with simulation. The results also show that the high sensitivity can be achieaved by decreasing the diaphragm thickness and increasing the diaphragm size.