Surface band bending, nitrogen-vacancy-related defects, and 2.8-eV photoluminescence band of $(NH4)2Sx$-treated p-GaN Available to Purchase

We have employed the photoluminescence and x-ray photoelectron spectroscopy measurements to study the effects of $(NH4)2Sx$ treatment on the p-type GaN $(p-GaN).$ After $(NH4)2Sx$ treatment, we found that the reduction of the surface state, related to nitrogen-vacancy defects on the p-GaN surface, led to a reduction in surface band bending by 0.25 eV. The surface band bending reduction and surface state reduction caused by the $(NH4)2Sx$ surface treatment could be useful for the formation of ohmic and Schottky contacts between the metal and p-GaN layers. In addition, the intensity of the 2.8-eV photoluminescence band depended on the amount of nitrogen vacancy of p-GaN, which was also investigated in this study.