HVPE Growth and Characterization of ε-Ga₂O₃ Films on Various Substrates

In this study we compare the growth of gallium oxide films by halide vapor phase epitaxy (HVPE) on various substrates under the same growth conditions. Gallium oxide films were deposited at 500 °C–600 °C on basal plane (0001) planar and patterned sapphire substrates, (0001) 2H-GaN, 4H-SiC, and 2 ¯ 01 bulk β-Ga₂O₃ substrates. The layers were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and cathodoluminescence (CL) techniques. Most of the films exhibit growth features of hexagonal symmetry. Sn-doped Ga₂O₃ films exhibit n-type electrical conductivity. Heterojunctions composed of n-type hexagonal Ga₂O₃:Sn and p-type GaN:Mg demonstrate diode-like I-V characteristics and emit light under forward bias.