Preparation, characterization and properties of B-doped β-Ga2O3 film

Abstract

In this paper, the B-doped β-Ga₂O₃ films were prepared by RF magnetron sputtering for the improved photovoltaic properties. It was found that the optical transmittance of the films achieved over 85 %, and the band gap was adjusted at range of 5.07-5.19 eV by doping B element. The PL spectra revealed the occurrence of self-trapped electrons and recombination of electrons-holes at the surface of films. Moreover, the good Ohmic contact was formed between the Ti metal electrode and B-doped β-Ga₂O₃ film, and the sheet carrier concentration were incresed from 1.78×10¹⁰ cm^-2 to 3.47×10¹⁷ cm^-2. The Hall mobility and the carrier concentration of the B-doped Ga₂O₃ film reached 9.71×10² cm²/V∙s and 6.19×10²³ cm^-3 at 40 W and 300 °C, The energy of B-forming interstitial doping was lower than the substitution doping calculated by first-principles, which confirmed the excellent photovoltaic properties for B-doped β-Ga₂O₃ film. This work provided a novel strategy for the improved electrical performance.