New Schottky-gate Bipolar Mode Field Effect Transistor (SBMFET): Design and Analysis using Two-dimensional Simulation

A new Schottky-gate Bipolar Mode Field Effect Transistor (SBMFET) is proposed and verified by two-dimensional simulation. Unlike in the case of conventional BMFET, which uses deep diffused p+-regions as the gate, the proposed device uses the Schottky gate formed on the silicon planar surface for injecting minority carriers into the drift region. The SBMFET is demonstrated to have improved current gain, identical breakdown voltage and ON-voltage drop when compared to the conventional BMFET. Since the fabrication of the SBMFET is much simpler and obliterates the need for deep thermal diffusion of P+-gates, the SBMFET is expected to be of great practical importance in medium-power high-current switching applications.