Study on the Single Event Burnout Mechanism of <i>β</i>-Ga₂O₃ Schottky Barrier Diode Under Heavy Ion Irradiation

The single event burnout (SEB) of beta-phase gallium oxide (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3) Schottky barrier diode (SBD) under 205 MeV germanium (Ge) ions irradiation has been studied systematically in this work. A typical SEB phenomenon was observed when the bias voltage reached 190 V. Technology computer-aided design (TCAD) simulation was used to explore the possible burnout mechanism. The local high lattice temperature peak induced by the impact ionization under a high electric field was proposed to explain the permanent damage. The incident-heavy ions will generate the electron-hole pairs along the incidence tracks, which gain enough energy with the aid of the high longitudinal electric field. The high-energy carriers will trigger severe impact ionization, resulting in large current density and noticeable heat accumulation along the ion track. When the local lattice temperature exceeds the melting-point temperature of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3 material, it will gradually lead to thermal damage and SEB will be triggered. Utilizing the scanning electron microscope (SEM), it is evidently observed that the burnout area crosses through the entire <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3 drift layer, which verifies the SEB mechanism. This research offers significant theoretical and experimental insights for evaluating the reliability of Ga2O3-based power devices against SEB in aerospace applications.