Degraded blocking performance of 4H-SiC rectifiers under high dV/dt conditions

Abstract

We present our pulsed blocking measurements of co-fabricated 4H-SiC Schottky, junction barrier Schottky (JBS), and pin diodes. Schottky diodes fail at pulsed voltages noticeably lower than their static values, while the pulsed leakage currents of JBS and pin diodes (along with commercial SiC rectifiers) remain below our measurable limits until the reverse voltage approaches the static breakdown. From experimental results and numerical simulations, the premature breakdown of the diodes is attributed to the slow response of deep levels associated with dopant implantation, which can leave high field points such as the edge of contacts unprotected under high dV/dt blocking conditions.