Growth temperature dependences of structural and electrical properties of Ga2O3 epitaxial films grown on β-Ga2O3 (010) substrates by molecular beam epitaxy

• We investigated the growth temperature dependence of Ga2O3 homoepitaxial films.
• Atomically smooth Ga2O3 films were obtained at growth temperatures of 550–650 °C.
• The doping delay of Sn in Ga2O3 occurred at higher than 600 °C.
• High-quality Ga2O3 films can be obtained in a narrow Tg range of 550–570 °C.

We investigated the growth temperature dependence of the structural and electrical properties of Sn-doped Ga2O3 homoepitaxial films grown on single-crystal β-Ga2O3 (010) substrates by molecular beam epitaxy. Ga2O3 films with an atomically smooth surface were obtained at growth temperatures of 550–650 °C. On the other hand, a delay in the incorporation of Sn atoms in Ga2O3, which was probably due to segregation, occurred in the initial stage of growth at higher than 600 °C. To ensure that Sn-doped Ga2O3 films with both high crystal quality and accurately controlled carrier density are obtained, the optimum growth temperature should be set at 540–570 °C.