Effect of Schottky annealing temperature on reverse leakage current of 6500 V 4H-SiC JBS diodes

•The Reverse leakage current of 6500 V 4H-SiC JBS diodes was studied.•The Schottky barrier height of 6500 V 4H-SiC JBS diodes was studied.•The relationship between Schottky barrier and reverse leakage current is analyzed and attained.•The decrease of Schottky barrier leads to the increase of the reverse leakage current. Annealing treatment has an important effect on the electrical properties of Schottky diodes. In this paper, the effect of Schottky annealing temperature on reverse leakage current of 6500 V 4H-SiC JBS diodes was studied. The reverse leakage current of the diode annealed at 500 °C is higher than that of the diode annealed at 450 °C. This is because the Schottky barrier height of the diode annealed at 500 °C is decreased by 0.08 eV, which leads to a large reverse leakage current. Meanwhile, the Schottky barrier height of the diode annealed at 500 °C is decreased more significantly with the increase of measurement temperature, therefore the reverse leakage current increases significantly.