Analysis of a pressure sensor based on an array of collector-assisted field-emission triodes

Abstract

The purpose of this paper is to analyze the operation of a pressure sensor based on an array of collector-assisted field-emission triodes (FETs). The silicon membrane (the anode of the device) put in front of the array is bent by the external pressure, and thus, the field-emission current is modified. An analytical solution has been used to calculate the deflection of the silicon diaphragm when the pressure is applied and a numerical model was developed for the single emitter FET. The array emission current is obtained adding the contributions of all the FETs in the array, no interaction between the emitters being considered. The device sensitivity and resolution have been computed as functions of both the silicon membrane and FET array parameters. Better sensor sensitivity and resolution are obtained for those situations, which assure higher field-emission currents. A simple analytical model was developed for the field-emission pressure sensor, supporting these observations. The obtained modeling results can be further used for sensor design improvement.