Design and Analysis of a Novel MEMS Touch Mode Convex Capacitive Pressure Sensor for Altimeter Applications

Abstract

The wide applications of Touch Mode Capacitive Pressure Sensors (TMCPS) have led the researchers working more on its performances. TMCPS have more acceptance due to their linearity, sensitivity, and ability to withstand more pressure which make them suitable for harsh environments. This study proposes a novel convex shape substrate to further improve the response of the TMCPS. This work provides a detailed mathematical and analytical modeling which upholds the proposed design. The analysis is compared with the simulation results from the software MATLAB. The simulated results have been compared with those reported in the existing literature. The linear operation range of the sensor is stretched more on the lower side (88[Formula: see text]KPa–2[Formula: see text]MPa) and the sensitivity is improved 2.85 times in touch mode, which completely fits in for the altimeter applications. This work also includes a detailed step-by-step process to be followed during the fabrication of the sensor. Sensor system characteristics such as nonlinearity, hysteresis and temperature dependence are also calculated in this work. The presented theory and simulation analysis fully supports the superior performance of the novel convex substrate square diaphragm TMCPS.