Surge absorption by the 430V mesa-structured SiC avalanche diode

We evaluate the surge absorption capability of the 430V SiC avalanche diode at the switched current 100A, corresponding to the current density 35.4kA/cm2 for the diode with the diameter 0.6mm. It is shown that, even at such a huge current density, the surge absorption has been successfully achieved with no device damage. We also investigate the effect of an additional stray inductor as well as a gate resistor of a MOSFET. It is found that the reduction of the stray inductance between a switching device and the SiC avalanche diode by, e.g., the co-pack configuration, is essential to realize an excellent surge absorption performance at a high speed turn-off event. The characteristics after the avalanche breakdown at 200$^{\circ}C$ implies that the surge absorption performance is not affected by a high ambient temperature.