An overview on the modeling of silicon piezoresistive pressure microsensors

This paper describes the modeling of a silicon piezoresistive pressure microsensor. The main feature involved in the design of a pressure sensor is the sensitivity. Here, the sensor sensitivity was related to the ratio between width and thickness of the diaphragm. The sensor was designed by an analytical solution. The diaphragm was considered a thin plate and the piezoresistors are arranged in the Wheatstone bridge configuration. This device analytically designed was analyzed by Finite Element Method (FEM). Four models were used to simulate the sensor: 2D diaphragm, 3D diaphragm, 1/4 of the sensor and entire sensor. Comparison between FEM and analytical results shows a small variation. The paper also discusses the linearity of the microsensor and the temperature effects.