Abstract: Radio frequency magnetron sputtering was used to deposit Mg doped Gallium oxide(Ga₂O₃) thin films with different Mg concentrations by alternate sputtering of Ga₂O₃ and MgO targets. The results showed that with the increase of Mg concentration, the crystallinity of the films decreased and the thickness of the films reduced; the light transmittance had no obvious change, but the band gap increased gradually, so we can change the band gap width of Ga2O3 film continuously by doping Mg into Ga2O3 film rangeing from 4.96 eV to 5.21eV; The PL spectroscopy results show that the doping of Mg leads to a blue shift of the PL peak, and a new luminescence peak appears near the 473 nm blue light.

Key words: radio frequency magnetron sputtering, Mg doped Ga₂O₃ film, Mg-doped concentration, optical band gap