Study on cut-off characteristics of sub-nanosecond silicon carbide PiN switch

Abstract

In this paper, a simulation model of [Formula: see text] type PiN high voltage pulse open switch is established. The switch operates in “punch through” mode, with a 4 kA/cm2 cut-off current density and sub-nanosecond cut-off speed. The cut-off process of switch can be divided into three stages, that is, non-equilibrium carriers extraction stage, majority carriers drift stage and charging stage of junction capacitance by change of internal electric field and carrier concentration. Keeping injection current and cut-off current as 20 A and 40 A, the switch cut-off speed and “pedestal” voltage are reciprocally determined. Thus, optimizing the doping concentration and thickness of [Formula: see text] layer is a valid solution for the actual system design.