Simulation Studies of Single-Event Effects in β-Ga₂O₃MOSFETs

In this article, we investigate the single-event effects (SEEs) leading to single-event burnout (SEB) in β-Ga2O3 MOSFETs. Using Silvaco TCAD, 2-D simulations were performed to understand the mechanism behind the SEB mechanism in lateral Ga2O3 MOSFETs. The high electric fields in the channel played a critical role leading to high impact generation rates and eventual SEB. To reduce the electric field in the channel, radiation-hardened designs are then proposed with rounded gates and the use of a combination of high-permittivity (k) dielectric with SiO2. With HfO2-SiO2 dielectric combination, the SEB threshold of 550 V at LET = 10 MeV/mg/cm2 is seen. However, to operate under extreme radiation conditions, a combination of very high-k dielectric material BaTiO3 with SiO2 is proposed. Using the radiation-hardened design, SEB thresholds up to 1000 V for LET = 75 MeV/mg/cm2 could be achieved which is higher than the state-of-the-art technology. The energy dissipated during the ion strike event is also calculated and it is observed that it is lower than that of SiC MOSFETs. However the energy dissipation value is not directly correlated with an SEB threshold condition.