Multi-Level Trap Assisted Tunneling Model for the Field and Temperature Dependence of SiC-JBS Reverse Leakage Current

The reverse-bias current-voltage characteristics of commercial 1200 V 4H-silicon-carbide junction barrier Schottky (SiC-JBS) rectifiers are studied both experimentally and through numerical simulation. The reverse leakage current measured from physical devices is observed to display both a strong temperature and field dependence. A model is presented to explain the observed behavior based on a combination of trap-assisted tunneling and a thermionic-emission mechanism through a potential barrier located at the metal-SiC interface. The study shows that a two-level trapping model can be necessary to properly explain the measured data. Excellent agreement between the models and the measurements is obtained over a wide range of bias and temperature.