The Establishment and Verification of the Sensitivity Model of the Piezoresistive Pressure Sensor Based on the New Peninsula Structure
Chengwu Gao, Dacheng Zhang
Abstract
In this paper, a mechanical-electrical-process integrated model of the piezoresistive pressure sensor sensitivity is established for the first time, and the nonlinearity is analyzed from two aspects of bridge arm resistance and piezoresistive stress difference. Furthermore, a new peninsula structure diaphragm (NPSD) piezoresistive differential pressure sensor is proposed. By creating stress concentration areas and adding the cross beam-circular boss structure, within the pressure range of 0–5 kPa, the sensitivity of the sensor measured by the experiment reaches 22.7 mV/kPa, and the nonlinearity is only 0.11%FSO (full-scale output). In addition, it has been proved theoretically and experimentally that the SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> passivation film seriously affects the zero output voltage of the sensor, and causes the nonlinearity of 1.22% FSO. At the same time, compared with several typical structures, the pressure sensor proposed has the advantages of high sensitivity, low nonlinearity and small diaphragm. [2021-0206]