Impact of Heavy-Ion Irradiation in an 80-V Radiation-Hardened Split-Gate Trench Power UMOSFET

In this work, the single-event burnout (SEB) and degradation behaviors induced by heavy-ion irradiation were investigated in an 80-V-rated SEB-hardened split-gate trench (SGT) power U-shaped metal-oxide-semiconductor field-effect transistor (UMOSFET). After SEB hardening, the SEB failure threshold voltage of the sample device was measured to be 90 V; furthermore, a permanent degradation of the drain leakage or gate leakage was found after irradiation when the reverse voltage exceeded 60 V. The simulation results demonstrate that the heavy-ion-induced transient high temperature is a common mechanism responsible for the severe degradation and the catastrophic SEB. In addition, an effective method to improve the degradation and SEB tolerances, which enhances the rated breakdown voltage of a device, was proven through simulations.