A Novel IGBT with Self-Regulated Potential for Extreme Low EMI Noise

Abstract

A novel insulated-gate bipolar transistor with self-regulated potential (SRP) for extreme low electro-magnetic interference (EMI) noise is proposed. The device features the superjunction (SJ) structure in the drift region and the integrated PN diode at the emitter side. In the turn-on transient, the lateral electric field brought by the SJ structure raises the potential under the gate oxide, which suppresses the hole accumulation at this region. The holes in the P-pillar are conducted to the emitter through the integrated PN diode between them. This could be effective in reducing the reverse displacement current that charges the gate capacitance, thus contributing to high dV/dt controllability and low EMI noise. Moreover, the PN diode clamps the potential of the P-pillar to provide a lower forward voltage drop ( ${V}_{ \mathrm{\scriptscriptstyle ON}}$ ) and higher short-circuit ruggedness. When compared with the Fin-P IGBT, the simulation results show that the proposed SRP-IGBT delivers a comparable breakdown voltage while featuring a 65% lower dV $_{\textsf {KA}}$ /dt, 25% lower ${V}_{ \mathrm{\scriptscriptstyle ON}}$ , and 46% longer short-circuit duration time simultaneously.