Analysis of Threshold Voltage Hysteresis on Switching Speed of SiC MOSFET with Kelvin and Non-Kelvin Packages

Abstract:
Silicon carbide (SiC) MOSFETs feature threshold voltage (VTH) hysteresis due to the high trap density at SiC/SiO2 interface. This paper investigates the effect of VTH hysteresis on the switching speed of SiC MOSFETs with Kelvin and non-Kelvin packages. It reveals that the non-Kelvin packaged devices exhibit larger current rise time variations (Deltatir) and turn-on losses variations (DeltaEon) under the same VTH hyste-resis compared to Kelvin counterparts. Moreover, Deltatir and DeltaEon is positively correlated with the common-source inductance (LCS), which further improves the sensitivity of the tir to VTH hysteresis of non-Kelvin packaged device. The above conclusions are confirmed by the double pulse tests.