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

Abstract

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.