Atmospheric Neutron-induced Single Event Burnout Characterization of 4.5 kV Si IGBTs with Spallation Neutron Irradiation

The atmospheric neutron-induced single event burnout (SEB) is observed for 4.5 kV Si IGBTs with trench gate structure by conducting spallation neutron source irradiation. The SEB is manifested as a random failure and is strongly related to the bias voltage. The SEB failure rates of two different Si IGBTs at different bias voltages are calculated based on the experimental results. It shows that the failure rates increase exponentially with bias voltages. For two different kinds of IGBTs, the atmospheric neutron-induced failure rate at an altitude of 4000 m is 0.855 FIT and 4.39 FIT, respectively, when biased at 60% of the rated voltage. When the bias voltage is increased to 64% of the rated voltage, the corresponding failure rates are increased to 24.7 FIT and 47.6 FIT. Furthermore, the SEB mechanisms for Si IGBTs are investigated by TCAD simulations.