Degradation of β-Ga₂O₃ Schottky barrier diode under swift heavy ion irradiation

The electrical characteristics and microstructures of β-Ga₂O₃ Schottky barrier diode (SBD) devices irradiated with swift heavy ions (2096 MeV Ta ions) have been studied. It was found that β-Ga₂O₃ SBD devices showed the reliability degradation after irradiation, including turn-on voltage V_on, on-resistance R_on, ideality factor n, and the reverse leakage current density J_r. In addition, the carrier concentration of the drift layer was decreased significantly and the calculated carrier removal rates were 5×10⁶-1.3×10⁷ cm^-1. Latent tracks induced by swift heavy ions were observed visually in the whole β-Ga₂O₃ matrix. Furthermore, crystal structure of tracks was amorphized completely. The latent tracks induced by Ta ions bombardments were found to be the reason for the decrease in carrier mobility and carrier concentration. Eventually, these defects caused the degradation of electrical characteristics of the devices. In terms of the carrier removal rates, the β-Ga₂O₃ SBD devices were more sensitive to swift heavy ions irradiation than SiC and GaN devices.