An Improved Turn-on Switching Transient Model of 10 kV SiC MOSFET

The emerging 10 kV SiC MOSFET brings great benefits for medium and high voltage applications, and is drawing increased research attention. Accurate switching transient modeling of the 10 kV SiC MOSFET is critical for successful application. Curve tracer is usually used to extract parameters needed for device modeling. However, the transconductance extracted from curve tracer is tested at low voltage, which is different from the transconductance during actual high voltage turn-on switching transient because of short channel effect and drain induced barrier lowering effect. Moreover, the gate-drain capacitance extracted from curve tracer is tested at static off-state, which is also different from the gate-drain capacitance during dynamic turn-on switching transient as the MOSFET channel is turned on in this process. Conventional models based on curve tracer tests show obvious discrepancies compared to experiments. This paper investigates and characterizes the high voltage transconductance and dynamic gate-drain charge of the 10 kV SiC MOSFET during turn-on switching transient. An improved turn-on switching transient model considering these factors is proposed. Experiments with the 10 kV 20 A SiC MOSFET are conducted and verify the accuracy of the proposed improved model.