Two Dimensional Modeling of Nonuniformly Doped MESFET Under Illumination

Abstract

A two dimensional numerical model of an optically gated GaAs MESFET with non uniform channel doping has been developed. This is done to characterize the device as a photo detector. First photo induced voltage (V op) at the Schottky gate is calculated for estimating the channel profile. Then Poisson's equation for the device is solved numerically under dark and illumination condition. The paper aims at developing the MESFET 2-D model under illumination using Monte Carlo Finite Difference method. The results discuss about the optical potential developed in the device, variation of channel potential under different biasing and illumination and also about electric fields along X and Y directions. The Cgs under different illumination is also calculated. It has been observed from the results that the characteristics of the device are strongly influenced by the incident optical illumination.