Research on the technique of accurately measuring thermal resistance of SiC MOSFET

The thermal resistance testing mechanism of SiC MOSFET is studied in this paper. The thermal resistance is an important performance parameter of SiC MOSFET. The shortcomings of traditional test methods are studied. Due to the difference of device structure and process level, the interface state in and near the gate oxygen of SiC MOSFET will affect the opening state of SiC MOSFET channels. The traditional thermal resistance test method is affected by this mechanism, which is not conducive to accurate evaluation of the thermal resistance of SiC MOSFET. In this paper, the method of SiC MOSFET temperature sensitive parameters is further studied. At the same time, comparative tests of thermal resistance tests are carried out for different current heating methods and combinations of temperature sensitive parameters. Based on the test results and mechanism analysis, the optimal thermal resistance evaluation method is given.