Experimental Investigation on Reducing Reverse Recovery Loss of SiC-MOSFET

Abstract

Compared with Si-IGBT, SiC-MOSFET is expected to reduce switching loss and conduction loss of the low current region, and also to remove external freewheeling diode. It is generally known that SiC-MOSFET body diode has a small reverse recovery charge, nevertheless it can generates large loss depending on operating condition because of pin diode structure. It has been reported that the reverse recovery charge of pin diode could be reduced by shortening diode conduction time for Si devices, however the effect on SiC-MOSFET body diode has not yet become clear. This work clarifies the effect of shortening diode conduction time in reducing reverse recovery charge of SiC-MOSFET body diode. It was confirmed that when the diode conduction time was shortened to 60 ns, the reverse recovery charge of SiC-MOSFET body diode could be reduced by approximately 60%.