Single Event Effect of E-Mode Ga2O3 Heterojunction Field Effect Transistor under Heavy Ion Irradiation

This paper investigates the damage mechanism of Single event effect (SEE) of enhancement-mode (E-mode) Ga2O3 heterojunction field effect transistor (HJ-FET) under high-energy heavy ion irradiation. The SRIM simulation method was used to study the damage distribution and linear energy transfer (LET) characteristics under the irradiation of bismuth (Bi) ions with an incident energy of 700 MeV. Combined with SILVACO TCAD, the transient current characteristics and carrier transport mechanism of the device under high-energy heavy ion irradiation were simulated. The results show that when the drain voltage is 240 V, heavy ions produce high concentration electron-hole pairs on the incident path due to ionization and excitation. Under the action of the applied electric field, the carrier drift produces a leakage current. Due to the accumulation of holes in the gate region, the potential barrier of the $\mathrm{p}-\mathrm{NiO} / \mathrm{n}-\mathrm{Ga}_{2} \mathrm{O}_{3}$ heterojunction is reduced, which significantly weakens the depletion effect of the heterojunction on the channel, triggering the interface tunneling effect and the back channel effect, resulting in an increase in the leakage current. As the hole continues to drift and diffuse, the gate current changes in the opposite direction, and the heterojunction space charge region is widened, which also makes the leakage current gradually recover. This study reveals the damage mechanism of single event transient failure induced by highenergy heavy ion irradiation through the coupling of ionization and excitation with carrier transport, which provides a theoretical basis for optimizing the radiation resistance design of $\boldsymbol{\beta}-\mathbf{G a}_{\mathbf{2}} \mathbf{O}_{\mathbf{3}}$ heterojunction devices