Evaluation of SiC MOSFET power modules under unclamped inductive switching test environment

• SiC MOSFET modules have been evaluated under unclamped inductive switching test environment
• Maximum avalanche current remained insensitive with variation of temperature
• The maximum amount of avalanche energy (EAS) sustained by the device before failure stays at 2.43 - 3.23 J for the tested power modules.
• SiC MOSFET modules prove to be electrothermally rugged and withstand higher temperature surges.

High power commercial SiC MOSFET modules have been evaluated under unclamped inductive switching (UIS) environment from the point of view of judging their failure ruggedness. The power modules with 1.7 kV/300 A and 1.2 kV/180 A rating were stressed with avalanche currents of their rated current value. One SiC MOSFET module sustained its avalanche current value when tested at rated forward current condition (i.e., 180 A) while the other power module failed during avalanche test even before reaching to its nominal rating current value (i.e., 300 A) at 25 °C. It is further shown that avalanche current of SiC-MOSFET modules is approximately insensitive of temperature variation under UIS behavior. A maximum avalanche energy of 2.43 and 3.23 J was extracted when tested at maximum avalanche current of 165 and 220 A for 1.7 kV/300 A and 1.2 kV/180 A rated power modules, respectively. These numbers far exceed than that of equivalent Si based IGBTs.