Effects of oxygen vacancies on the optical and electrical performances of silicon-based Er doped Ga₂O₃ films

Abstract Effects of oxygen vacancies on the optical and electrical properties of silicon-based Er doped Ga2O3 films are investigated. The content of oxygen vacancies can be tuned by changing the Ar:O2 flow ratios during sputtering, and the films sputtered in pure Ar are proved to possess the most oxygen vacancies by the calculations of energy band structure and carrier concentration. It is found that oxygen vacancies are involved in the process of indirect Er3+ ions related emission. With more oxygen vacancies introduced, the conductivity and energy transfer efficiency of Er doped Ga2O3 films can be enhanced simultaneously, leading to the increasing electroluminescence intensity of the light-emitting devices. The optimized silicon-based devices present the maximum optical power density of ~2 μW/cm2.