Investigation into Short-Circuit Ruggedness of 1.2 kV 4H-SiC MOSFETs

摘要

The shout-circuit ruggedness of prototype 1,2kV SiC MOSFETs has been investigated. The short-circuit measurements were carried out at 25 °C and 125 °C with a dc bus voltage of 800 V and an on/off state gate voltage of+20/-10 V. The small difference in t_(fail) between 25 °C and 125 °C indicates that the destructive breakdown occurs at temperatures much higher than 125 °C. The temperature at destructive breakdown estimated from the Wunsch-Bell formula is about 1400 °C. At such high temperatures, intrinsic carriers are increased markedly and generated heat leads to the destructive breakdown. t_(fail) of all the SiC-MOSFETs studied is longer than 10 μs, meaning that the short-circuit ruggedness satisfies system requirements. These results show that the SiC-MOSFETs are promising for power electronics applications.