Numerical model for determining the switching characteristics of GaAs-MESFET with non-uniform doping profile in the channel

Abstract

A numerical model of an ion-implanted GaAs Metal-Semiconductor-Field Effect-Transistor (MESFET) has been presented. The model enables one to determine the exact potential profile in the channel and the variation of gate depletion width and substrate depletion width in the channel as a function of position between the source and the drain for an arbitrary doping profile in the channel. This model can be used to determine numerically the drain current - drain voltage characteristics, transfer characteristics, the transconductance and various inter-electrode capacitances like gate-to-source capacitance, gate-to-drain capacitance, substrate capacitance etc. The model can be used as a basic tool for simulation MESFET based circuits.