Terrestrial Neutron-Induced Failures in Silicon Carbide Power MOSFETs and Diodes

Abstract

Investigations of terrestrial neutron radiation-induced failures in silicon carbide power MOSFETs and diodes indicate that the failures are related to a hole-initiated impact ionization process followed by a thermal transient resulting in the loss of device voltage blocking ability due to the damage of lattice along a filament within the device volume. Irrespective of device type, MOSFET or diode, the start of these failures exhibits the same characteristics, and can be mitigated by decrease in field in device OFF state. These failures with origins in impact ionization and fast thermal transients are fundamentally different from those of bipolar burn-out events, observed in silicon power devices. In addition, once a failure event starts, the failure ends with all terminals shorting.