Red Luminescence in H-doped beta-Ga2O3

• Published in: arXiv.org 2020-07
• Main Authors: Thanh Tung Huynh, Chikoidze, Ekaterine, Irvine, Curtis P, Zakria, Muhammad, Dumont, Yves, Teherani, Ferechteh H, Sandana, Eric V, Bove, Philippe, Rogers, David J, Phillips, Matthew R, Ton-That, Cuong
• Format: Article
• Language: English
• Subjects: Binding energy; Cathodoluminescence; Coordination compounds; Electrical properties; Electrical resistivity; Gallium oxides; Luminescence; Optical properties; Photoelectric emission; Thin films
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2005.13743

The effects of hydrogen incorporation into beta-Ga2O3 thin films have been investigated by chemical, electrical and optical characterization techniques. Hydrogen incorporation was achieved by remote plasma doping without any structural alterations of the film; however, X-ray photoemission reveals major changes in the oxygen chemical environment. Depth-resolved cathodoluminescence (CL) reveals that the near-surface region of the H-doped Ga2O3 film exhibits a distinct red luminescence (RL) band at 1.9 eV. The emergence of the H-related RL band is accompanied by an enhancement in the electrical conductivity of the film by an order of magnitude. Temperature-resolved CL points to the formation of abundant H-related donors with a binding energy of 28 +/- 4 meV. The RL emission is attributed to shallow donor-deep acceptor pair recombination, where the acceptor is a VGa-H complex and the shallow donor is interstitial H. The binding energy of the VGa-H complex, based on our experimental considerations, is consistent with the computational results by Varley et al [J. Phys.: Condens. Matter, 23, 334212, 2011].