A simple and efficient technique for the simulation of capacitive pressure transducers

Abstract

This paper presents a simple and efficient technique which is capable of representing the relationship between diaphragm deflection and capacitance change with pressure in closed form expression for square clamped-edge thin silicon diaphragm capacitive pressure transducer. This technique has been obtained based upon a thermoelastic plane-stress formulation of the deflection and stress equations and on a solid-state process oriented model of the silicon capacitive pressure transducers. As a result of this study, the deflection of the diaphragm in response to a change of differential pressure is measured by the capacitive change of the capacitor. The application of the developed technique in evaluating the output frequency of the capacitor-controlled oscillator and the output voltage of the charge measurement circuit as a function of applied pressure are also investigated.