A high reliable reverse-conducting IGBT with a floating P-plug

A current distribution model is presented for the RC-IGBTs both at IGBT mode and DIODE mode. According to the analytical model, smaller cell size would be better for the distribution of the current density and full utilization of the silicon, but the snapback would be worse. Then a novel RC-IGBT with a floating P-plug is proposed and investigated by simulations. The results show that it can suppress the snapback phenomena effectively. More importantly, the silicon utilization ratio is much higher than the others RC-IGBTs and the current is uniformly distributed in the whole wafer both at IGBT mode and DIODE mode that ensured the high temperature reliability of the RC-IGBT.