Novel Diode Structure for Ultra-Law-Loss RC-IGBTs

Reverse conducting integrated gate bipolar transistor (RC-IGBT) features a monolithically integrated diode. In the case of diodes, a lifetime killer is generally introduced because of large switching losses caused by accumulated carriers during forward conduction. However, lifetime killer causes an increase in IGBT on-resistance. This study proposes Schottky and Multi-layered Anode (SMA) structures for low loss RC-IGBT to control diode performance while maintaining IGBT characteristics. Results show that the proposed structure reduces the reverse recovery charge by 41 % compared to a conventional structure. In contrast, in the IGBT characteristics, the threshold voltage, on-voltage, and turn-off characteristics remain practically unchanged.