Simulation and Optimization of Aluminum Based Touch Mode Micro-Machined Capacitive Pressure Sensors

Authors: .K.Aryantalab1*, Y.Hezarjaribi2

Affiliations:

1kianosh Aryantalab

?University of Golestan_Faculty of Technical and Engineering _Gorgan

*email:[email protected]

2Dr.Yadolah Hezarjaribi

? University of Golestan_Faculty of Technical and Engineering _Gorgan

*email: [email protected]

Abstract: This paper discusses the Electro-mechanical effects on Aluminum thin film as a diaphragm for MEMS capacitive pressure sensor. This work compares the design of an Aluminum diaphragm based MEMS capacitive pressure sensor as square and round Geometry on the top layer. Aluminum Diaphragm, cavity gap and Al substrate thickness are fixed on 2μm.Width and length of the square geometry are equal to diameter of the round one and fixed on 50μm. The sensor designs were simulated using COMSOL ver5.0 software to compare the diaphragm deflection and electrical energy performance. Both Geometry are designed with the same layout dimensional with same thicknesses of the diaphragm which is 2μm. It is observed that the square diaphragm is better geometry than round one for the similar pressure load. Maximum and Average displacement, Electric potential and effect of diaphragm dimension on capacitance are discusses on the square sensor. Finally a comparison has been made between Aluminum, Silicon and Polysilicon as a material for deflecting membrane. It can be seen that Aluminum in similar condition has more deflection than Si and Polysilicon.

Keywords: MEMS, Sensor, Aluminum, Square, Round, Diaphragm, Electric Potential.