Characterization Of On-State Resistance By Interface Defects In SiC MOSFETs

As a new generation of wide band gap semiconductor material, silicon carbide (SiC) material can greatly reduce the power loss in power electronic system and improve the power integration based on its advantages of high voltage resistance, high temperature resistance and low loss. Compared with traditional Si devices, the introduction of C element and the defects of SiC wafer itself lead to a large number of defects and fixed charges at the gate-oxygen interface, which makes the channel mobility of SiC MOSFET far less than the bulk mobility, reduces the on-current capability of SiC MOSFET and increases the loss of the device. In this paper, the current commercial 1200V SiC MOSFET device is used as the experimental object. The changes of the basic characteristics of the device under the static and dynamic response of the defect at different temperatures are analyzed, and a convenient characterization method is used to study and analyze the change of the on-resistance of the device caused by the defect.