A Snapback Suppressed RC -IGBT With N-Si/n-Ge Heterojunction at Low Temperature

This article proposes an RC -IGBT structure with N-Si/n-Ge heterojunction (NNH-IGBT) to suppress snapback effect. Because the proposed N-Si/n-Ge heterojunction acts as a gradually reverse bias diode to suppress the electron flow into the N-short region, so the snapback effect can be suppressed. For the same ${\mathrm{\scriptstyle {ON}}}$ -state voltage drop ( ${V}_{\text {CE}}$ ), the turn-off loss ( ${E}_{\mathrm{\scriptstyle {OFF}}}$ ) of the NNH-IGBT is lower than the conventional RC -IGBT (Con- RC -IGBT). In addition, the reverse recovery speed of NNH-IGBT is nearly identical to the Con- RC -IGBT. Because of the use of heterojunction, the NNH-IGBT is suitable for operate to suppress the snapback effect, especially at low temperatures.