Analytical and Simulation Evaluation for Diaphragm’s Deflection and its Applications to Touch Mode MEMS Capacitive Pressure Sensors

In this paper, An analytical and simulation solution for touch mode Micro-electromechanical systems (MEMS) capacitive pressure sensor operating in harsh environment is proposed, The principle of the paper is to design, obtain analytical solution and compare the results with the simulation using coventor software for a circular diaphragm deflection before and after touch point. The material is considered to be used for harsh environment is SiC (Silicon Carbide), Because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties and the application of pressure sensors in harsh environments are, such as automotive industries, aerospace, oil/logging equipments, nuclear station, and power station. We are using coventor software for modeling and simulating of MEMS capacitive pressure sensor to optimize the design, improve the performance and reduce the time of fabricating process of the device. The device achieved a linear characteristic response and consists of a circular clamped-edges poly-SiC diaphragm suspended over sealed cavity on a poly-Sic substrate. The proposed touch mode MEMS capacitive pressure sensor demonstrated diaphragm ranging from 150ìm to 360ìm in diameter, with the gap depth from 0.5ìm to 6ìm and the sensor exhibit a linear response with pressure from 0.05 Mpa to 10 Mpa.