Surface defect compensation of Ga2O3 thin films N-doped by nitrogen plasma for enhanced electrical performance and luminescence effect

Abstract

Nitrogen (N) doping engineering is considered a promising approach to achieve p-type conductivity of Ga2O3 films. However, the defect self-compensation effect has been a major obstacle in this field. In this work, we propose a straightforward and environmentally friendly strategy to obtain a doped surface on β-Ga2O3 films via nonthermal N plasma-based treatment. By substituting nitrogen with oxygen, acceptor impurity levels are formed near the valence band, and self-trapped exciton recombination occurs, thereby enhancing the luminescence effect related to acceptor defects. Meanwhile, although achieving stable p-type conduction with N dopant acceptors remains challenging, the surface conductive properties are enhanced by the defect compensation of oxygen vacancy (VO) donor defects. Therefore, detailed investigations into the surface defect compensation of N-doped Ga2O3 thin films are of great research potential for device applications.