Investigation on the use of the MOSFET SiC body diode for junction temperature measurement

International audienceAs Silicon-based semiconductors approach their limits in different areas, wide bandgap devices, such as Silicon Carbide components, offer an excellent alternative in many applications. Recently, SiC MOSFETs are replacing Si-based IGBT in various fields as automotive, solar energy… The junction temperature is important to evaluate the performance and the reliability of these components. For Silicon MOSFET, the body diode is usually used as a thermal sensitive electrical parameter (TSEP) for junction temperature measurement. For SiC MOSFET, however, in gate-source short configuration (VGS=0V), some current still flows through the channel, which, with interface trapping, prevents from accurately estimating SiC MOSFET junction temperature. Practically, a sufficiently negative gate voltage VGS (-5V or below, depending on devices) must to applied to eliminate the current part through the MOS channel so that the body diode forward voltage is immune from interface trapping