Influence of recovery characteristics on switching behavior of SiC MOSFETs

Abstract

The effect of recovery characteristics on the switching behavior of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) is investigated on the basis of the output capacitance charge of the recovery arm (Q oss ) and the reverse recovery charge by minority carrier injection (Q rec ). It is confirmed that the variation of drain current during switching operation due to the increase in Q oss and Q rec modifies the rise or fall time of drain-source voltage, which results in an increased turn-on loss and a decreased turn-off loss of SiC MOSFETs. Furthermore, a substantial impact of Q oss and Q rec on switching loss for faster switching speed is observed because of the enlarged variation of drain current. These results suggest the necessity of careful consideration of the effect of Q oss and Q rec on switching loss to realize future high-frequency systems using SiC MOSFETs.