Determining 4H silicon carbide electronic properties through combined use of device simulation and metal–semiconductor field-effect-transistor terminal characteristics

Abstract

A two-dimensional numerical device simulator has been developed specially for the recessed gate 4H silicon carbide(4H-SiC) metal–semiconductor field-effect-transistor (MESFET). By combining numerical techniques, material physics, and measured device characteristics, we are able to use the simulator to extract more information about the new material 4H-SiC, including the mobility, velocity-field curves, and the Schottky barrier height. We have also enabled and used the new simulator to investigate breakdown voltage and thus predict operation limitations of the 4H-SiC device. Simulations indicate that impact ionization is relatively small in 4H-SiC, thereby leading to a very high breakdown voltage of 125 V in a 0.7 μm gate MESFET.