Beyond a single mechanism: Uncovering the dual origin of degradation in <b> <i>β</i> </b> -Ga2O3 SBDs under forward bias stress

Abstract

This study delineated the degradation of β-Ga2O3 Schottky barrier diodes under forward bias stress and identified the physical cause of performance instability in these diodes. Stress was found to increase the reverse leakage current and the forward current under low biases and decrease the turn-on voltage. The values of these parameters were partially recovered after annealing. The increased noise power spectral density after stress application was completely recovered after annealing, indicating that device degradation caused by interface defects is reversible. From the temperature-dependent low-frequency noise results, the interface defect energy levels were determined to be about EC −0.35 eV (EC = conduction band minimum). Deep-level transient spectroscopy technology traced the remaining irreversible degradation to E2* bulk defects. This dual-mechanism framework provides a clear physical explanation of degradation and offers crucial insights for enhancing the long-term stability of Ga2O3 power devices.