New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET) without PN Junction

Abstract

The bipolar mode field effect transistors (BMFETs) using P+ gates on N-type silicon substrate are the most commonly used power devices for high-current medium-power switching applications and as optically controlled switches. These are dual gate devices with deep P+ gate junctions, which require large thermal cycles for diffusion. In this paper, we propose a novel Schottky-gate BMFET (SBMFET) using P-type 4H silicon-carbide, a wide bandgap material, in which the PN junction gates are replaced by the Schottky gates. We have studied the characteristics of this device using two-dimensional numerical simulation. Our results demonstrate for the first time that the P-SiC Schottky-gate BMFET has very low ON voltage drop, good output characteristics, a reasonable current gain and a blocking voltage greater than 1000 V