Halide vapor phase epitaxy of Si doped β-Ga2O3 and its electrical properties

Silicon doped homoepitaxial films were grown on beta‑gallium oxide (001) substrates by halide vapor phase epitaxy using gallium monochloride, oxygen and silicon tetrachloride gases as precursors. It was confirmed that the n-type carrier density at room temperature was almost equal to the doped silicon concentration, which was controlled in the range of 1015 to 1018 cm−3. In the doped film with the carrier density of 1 × 1016 cm−3, the activation energy and the mobility at room temperature were 45.6 meV and 145 cm2/V⋅s, respectively. The carrier scattering mechanism in the low carrier density film was dominated by optical phonon scattering with the phonon energy of 33 meV. These results suggest that the doped homoepitaxial film grown by halide vapor phase epitaxy is a high quality film with good crystallinity comparable to bulk crystals. •Succeeded in doping control of gallium oxide homoepitaxial film by HVPE method.•The activation energy and the scattering mechanism of the carriers were clarified.•A high mobility of 5000 cm2/V·s close to the theoretical value was shown.