Modeling of the Snappy, and Soft Reverse Recovery of SiC MOSFET's Body Diode

Different reverse recovery modes of the SiC MOSFET's body diode are investigated in this paper. Using semiconductor device simulation, the operating conditions under which snappy, and soft reverse recovery occur in power electronics applications are better explained. The work presented here verifies that the snappy or soft recovery is dependent on the dynamic carrier distribution in the drift region during reverse bias. The Compact Modeling Coalition (CMC) p-i-n diode model is used to model the body diode of SiC MOSFET because it contains the requisite equations and parameters for the dynamic distribution of carriers. The physics-based model includes parameters for bias-dependent depletion layer, separate anode and cathode injection, and non-quasi-static charge distribution. Consequently, the model permits simulation of the snappy, and soft reverse recovery of the body diode based on external circuit conditions. The paper verifies the model by comparing simulation results to measured switching data at various temperatures, and gate resistances. This modeling exercise can facilitate the power electronics system's optimal design.