High-Temperature Characterization of a 1.2-kV SiC MOSFET Using Dynamic Short-Circuit Measurement Technique

摘要

Threshold voltage and channel mobility of a 1.2-kV planar-channel SiC MOSFET at high junction temperature ( $T_{j}$ ) up to 700 degrees C have been extracted and analyzed for the first time, by virtue of a specially designed short-circuit (SC) measurement technique we developed. Under the SC condition, $T_{j}$ of the SiC MOSFET can rise significantly within a few microseconds, which can be extracted based on the SC waveforms and thermal calculations. The planar-channel SiC MOSFET investigated in this work can maintain normally-off operation at an elevated $T_{j}$ up to 700 degrees C. Furthermore, the underlying mechanisms of the temperature dependence of the threshold voltage and channel mobility are also analyzed. The threshold voltage of the SiC MOSFET exhibits a different temperature dependence over a wide range (120-700 degrees C) compared with that of Si counterparts, which is attributed to interface traps' response. The channel mobility shows a non-monotonic temperature dependence, due to divergent scattering mechanisms.