Impact of surface morphology above threading dislocations on leakage current in 4H-SiC diodes

The nano-scale pits above the threading dislocations were found to be in the same location as the leakage current points in Schottky barrier diodes and junction barrier Schottky diodes. This study compared the leakage current of 1.2 kV, 200 A diodes with and without nano-scale pits. The leakage current in diodes without nano-scale pits was lower than those in diodes with pits. In the diodes without nano-scale pits, the leakage currents were generated at step-bunching area and the leakage current at the threading dislocations was not observed.