Enhanced epitaxial growth of Ga2O3 using an ultrathin SnO2 layer

Abstract

The tin-enhanced growth of [Formula: see text] on (0001) [Formula: see text] by plasma-assisted molecular beam epitaxy using an ultrathin [Formula: see text]-layer of [Formula: see text] is demonstrated. It is shown that this growth method results in a significantly reduced incorporation of residual Sn in the [Formula: see text] film compared to the case of permanent Sn-supply. The ultrathin [Formula: see text] layer, pre-deposited on the substrate, is sufficient to initiate phase pure growth of [Formula: see text]-[Formula: see text] in metal-rich growth conditions where otherwise no growth occurs. The chemical and morphological properties of the [Formula: see text]-layer are analyzed and the presence of [Formula: see text] on the surface during the entire growth process is demonstrated. Furthermore, we show that this layer is stable during Ga-induced back-etching of a [Formula: see text] film. Its impact on the kinetics of [Formula: see text] growth is also discussed.