Bandgap Engineering and Oxygen Vacancy Defect Electroactivity Inhibition in Highly Crystalline N-Alloyed Ga2O3 Films through Plasma-Enhanced Technology

Previous research has shown that the hybridization of N 2p and O 2p orbitals effectively suppresses the electrical activity of oxygen vacancies in oxide semiconductors. However, achieving N-alloyed Ga₂O₃ films, known as GaON, poses a significant challenge due to nitrogen's limited solubility in the material. In this study, a new method utilizing plasma-enhanced chemical vapor deposition with high-energy nitrogen plasma was explored to enhance the nitrogen solubility in the material. By adjusting the N₂ and O₂ carrier gas ratio, we could tune the thin film's bandgap from 4.64 to 3.25 eV, leading to a reduction in the oxygen vacancy density from 32.89% to 19.87%. GaON-based photodetectors exhibited superior performance compared to that of Ga₂O₃-based devices, with a lower dark current and a faster photoresponse speed. This investigation presents an innovative approach to achieving high-performance devices based on Ga₂O₃.