Physical mechanisms for gate damage induced by heavy ions in SiC power MOSFET

The objective of the paper is to present a trap assisted conduction mechanism able to explain the creation of a conductive path in the gate oxide of SiC power MOSFET during the impact of heavy ions. The consequent large current flow through the oxide can induce damages to the gate structure. The proposed mechanism combines a Fowler-Nordheim tunneling at the SiC/SiO2 interface with a trap-assisted valence band conduction mechanisms based on Poole-Frenkel effect. The model is based on the results of 2D finite element simulation and is supported by previous works dealing with trap assisted tunneling hole injection in silicon dioxide.