Study on the synergistic effect of electrical bias and proton irradiation on the electrical performance degradation of β -Ga2O3 Schottky barrier diodes

In this work, the synergistic effect of 5 MeV proton irradiation and different biases on the electrical performance of a β-Ga2O3 Schottky barrier diode was studied. Experimental results demonstrate that proton irradiation leads to significant degradation in electrical performance with increasing proton fluence, manifested as decreased forward current density, reduced reverse current density, and increased breakdown voltage. Based on deep-level transient spectroscopy and capacitance–voltage measurements, the degradation is attributed to the introduction of an electron trap at the energy level of EC-0.75 eV (gallium vacancy-related defect) within the drift layer during irradiation. Furthermore, the introduction of an off-state bias during proton irradiation results in more severe degradation of the electrical performance of the device relative to the case of proton irradiation without bias. Molecular dynamics simulations and theoretical analysis reveal that this enhancement in degradation is attributed to the applied electric field that suppresses the recombination of gallium vacancies–interstitial atoms and elevates the energy of low-energy secondary particles, thereby promoting the formation of gallium vacancy-related defects.