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Abstract Films of α-Ga2O3 (Sn) grown by Halide Vapor Phase Epitaxy (HVPE) on sapphire with starting net donor densities in the range 5×1015- 8.4×1019 cm-3 were irradiated at room temperature with 1.1 MeV protons to fluences from 1013 -1016 cm-2. For the lowest doped samples, the carrier removal rate was ~35 cm-1 at 1014 cm-2 and ~1.3 cm-1 for 1015 cm-2 proton fluence. The observed removal rate could be accounted for by the introduction of deep acceptors with optical ionization energies of 2 eV, 2.8 eV and 3.1 eV. For doped samples doped at 4x1018 cm-3, the initial electron removal rate was 5×103 cm-1 for 1015 cm-2 proton fluence and ~300 cm-1 for 1016 cm-2 proton fluence. The same deep acceptors were observed in photocapacitance spectra, but their introduction rate was orders of magnitude lower than the carrier removal rate. For the heaviest doped samples, an electron removal rate could be measured only after irradiation with the highest proton fluence of 1016 cm-2 and was close to that measured for the 4×1018 cm-3 sample after exposure to the same fluence. Possible reasons for the observed behavior are discussed and radiation tolerances of lightly doped α-Ga2O3 films is higher than for similarly doped β-Ga2O3 layers.  

Films of α-Ga 2 O 3 grown by Halide Vapor Phase Epitaxy (HVPE) were irradiated with protons at energies of 330, 400, and 460 keV with fluences 6 × 10 15  cm −2 and with 7 MeV C 4+ ions with a fluence of 1.3 × 10 13  cm −2 and characterized by a suite of measurements, including Photoinduced Transient Current Spectroscopy (PICTS), Thermally Stimulated Current (TSC), Microcathodoluminescence (MCL), Capacitance–frequency (C–f), photocapacitance and Admittance Spectroscopy (AS), as well as by Positron Annihilation Spectroscopy (PAS). Proton irradiation creates a conducting layer near the peak of the ion distribution and vacancy defects distribution and introduces deep traps at E c -0.25, 0.8, and 1.4 eV associated with Ga interstitials, gallium–oxygen divacancies V Ga –V O , and oxygen vacancies V O . Similar defects were observed in C implanted samples. The PAS results can also be interpreted by assuming that the observed changes are due to the introduction of V Ga and V Ga –V O .