Si-doped (AlGa)2O3 growth on a-, m- and r-plane α-Al2O3 substrates by molecular beam epitaxy

Abstract

We reported the growth of (AlGa)2O3 layers on (11 2¯ 0), (10 1¯ 0), and (10 1¯ 2) α-Al2O3 substrates using MBE, and the electrical characterization of Si-doped (AlGa)2O3 layers. The Ga2O3 layers grown on (10 1¯ 0) and (10 1¯ 2) α-Al2O3 were α-phase single crystals, while the Ga2O3 layer grown on (11 2¯ 0) α-Al2O3 consisted of (11 2¯ 0) α-Ga2O3 and ( 2¯ 01) β-Ga2O3. The Al composition of the (11 2¯ 0) and (10 1¯ 0) (AlGa)2O3 layers was controlled by varying the Al flux. The Si-doped (10 1¯ 0) α-(Al x Ga1-x )2O3 layers with x = 0–0.41 were electrically conducting.