Influence of Trench Structure on Reverse Characteristics of 4H-SiC JBS Diodes

We fabricated trench Junction Barrier Schottky (JBS) diodes, and investigated the effect on the reduction of leakage current and the device yield. First, by calculating of electric field at the Schottky contact interface (Es), we found that the trench JBS structure can reduce Es one digit smaller than the planar JBS structure, setting 80o < The bevel angle θ < 90o. Then, 600 V / 50 A trench JBS diodes are developed and characterized. The leakage current of a trench JBS diode at 600V is 10-2 times smaller than that of planar JBS diode by effectively reducing Es. This enables to reduce the number of low break down samples and raise the yield compared to the planar JBS structure.