Crystal orientations of β-Ga2O3 thin films formed on n-plane sapphire substrates.

We have used X-ray pole figure analysis to study crystal orientations of β-Ga2O3 thin films deposited on (113) n-plane sapphire substrates by gallium evaporation in oxygen plasma. The films were strongly (−201)-oriented. However, the (−201) plane of β-Ga2O3 on the (113) n-plane sapphire was inclined along the (110) a-plane. Crystals of (−201)-oriented β-Ga2O3 exhibit a threefold symmetry in which the β-Ga2O3 crystal is rotated by increments of 120° from the direction of the c-axis on the a-plane of sapphire. The crystal orientation of β-Ga2O3 was explained by comparing oxygen atom arrangements on the β-Ga2O3 plane in three different configurations and on the (113) n-plane sapphire substrates. [ABSTRACT FROM AUTHOR]