Synergistic mechanism underlying the enhanced electrical performance of vertical <i>β</i>-Ga2O3 Schottky barrier diodes through proton irradiation and annealing

Abstract

This study presents the enhancement of the electrical performance in vertical β-Ga2O3 Schottky barrier diodes (SBDs) through proton irradiation followed by annealing processes, along with the underlying physical mechanisms. Initially, the rectification behavior of these SBDs is significantly degraded following 5 MeV proton irradiation. However, for the device treated post annealing, following irradiation (D1-A500), the carrier concentration (ND) decreases by 72.1%, while the breakdown voltage (BV) increases by 124.5%. Deep level transient spectroscopy analysis reveals an increase in the concentration of acceptor traps, E2* (EC-0.74 eV), and the appearance of a new defect peak, E2 (EC-0.86 eV), attributed to proton irradiation and subsequent annealing. E2 is possibly associated with oxygen antisites (OGaII). Further simulations using technology computer aided design further verify that a reduction in ND improves the BV. Therefore, these findings elucidate the effect of proton irradiation on vertical β-Ga2O3 SBDs and emphasize the recovery of the devices by post-annealing treatment, providing valuable insights for application in radiation environments.