An Ultralow Loss Insulated Gate Bipolar Transistor With Emitter Dual Injection

Abstract

A novel trench insulated gate bipolar transistor (IGBT) with emitter dual injection (EDI-IGBT) is proposed and investigated. The device features the hybrid gate electrode and the tiny P-base. The hybrid gate is a combination of the conventional trench gate (TG) and the accumulation gate (AG). The TG contacts the P-base region and the N-drift region, while the AG contacts the N-drift region only. In the ON-state, the accumulation layer formed by the AG makes an additional accumulation injection in the emitter side, leading to the EDI phenomenon, and hence a low forward voltage drop ( ${V}_{ \mathrm{\scriptscriptstyle ON}}$ ). Simultaneously, the tiny P-base region reduces holes extracted by the reverse-biased p-base/n-drift junction, which also contributes to the reduction in ${V}_{ \mathrm{\scriptscriptstyle ON}}$ . The simulation results show that the EDI-IGBT delivers comparable breakdown voltage and safe operating area (SOA) while featuring a 28% lower ${V}_{ \mathrm{\scriptscriptstyle ON}}$ , resulting in a reduction in total energy loss. Moreover, the existence of the AG suppresses the gate self-charging effect during the turn-on transient, leading to an improved turn-on performance. The excellent device performance, coupled with industry-standard IGBT-compatible fabrication process, makes the proposed EDI-IGBT a promising candidate for power switching applications.