Junction Temperature Measurement of SiC MOSFETs: Straightforward as it Seems?

Reliable measurement of the junction temperature Tj is essential for the application of power semiconductors. Similar to the IGBT's Vce-method, for SiC MOSFETs the voltage drop over the body diode can be used for Tj acquisition. This method is validated for different devices with consideration of the gate voltage's and measuring current's influence. Furthermore, the applicability of the Rgi-method, which also works in switching operation and utilizes the temperature coefficient of the internal gate resistance, is evaluated for SiC MOSFETS.