Recombination-induced stacking fault degradation of 4H-SiC merged-PiN-Schottky diodes

The increase in the forward voltage drop observed in 4H-SiC bipolar devices due to recombination-induced stacking fault (SF) creation and expansion has been widely discussed in the literature. It was long believed that the deleterious effect of these defects was limited to bipolar devices. Recent reports point to similar degradation in 4H-SiC DMOSFETs, a primarily unipolar device, which was thought to be SF-related. Here we report similar degradation of both unipolar and bipolar operation of merged-PiN-Schottky diodes, a hybrid device capable of both unipolar and bipolar operation. Furthermore, we report on the observation of the temperature-mediation of this degradation and the observation of the current-induced recovery phenomenon. These observations leave little doubt that this degradation is SF-induced and that if SFs are present, that they will adversely affect both bipolar and unipolar characteristics.