Investigation of the avalanche ruggedness of SiC JBS diodes with floating limiting rings under single unclamped-inductive-switching stress

In this paper, the single pulse avalanche robustness of SiC Junction Barrier Schottky (JBS) diode with different termination designs is investigated with simulations and experiments. Planar floating limiting rings (FLRs) and trench FLRs for the JBS diodes are designed and fabricated, and their avalanche current and energy capabilities are evaluated by unclamped inductive switching tests. The experiment and simulation indicate that a moderate first ring spacing window (S1) can achieve better device performance. Additionally, the single avalanche current stress measurements imply that the JBS diode with trench FLRs has better robustness and achieves better device reliability.