Analysis of gate voltage oscillation in a module with combination of Si-IGBT and SiC Schottky Diodes

In recent years, oscillation phenomena are often observed in IGBT power modules at turn-on, turn-off and short-circuit. This oscillation phenomenon causes not only electromagnetic interference (EMI) to other electronic devices due to radiated electromagnetic waves but also a gate breakdown in the worst case. According to experimental result, a high frequency oscillation during turn-on was observed in a module with the combination of Si-IGBT and SiC schottky barrier diode. The oscillation was not seen with the combination of Si-IGBT and Si-FWD. The oscillation was reproduced in simulation and the amplitude was depends on the large junction capacitance of SiC schottky barrier diode.