Wang, C.Y.C.Y.WangKirste, LutzLutzKirsteMorales, F.M.F.M.MoralesMánuel, J.M.J.M.MánuelRöhlig, C.-C.C.-C.RöhligKöhler, KlausKlausKöhlerCimalla, VolkerVolkerCimallaGarcía, R.R.GarcíaAmbacher, OliverOliverAmbacher2022-03-042022-03-042011https://publica.fraunhofer.de/handle/publica/22610110.1063/1.36582172-s2.0-81355142834In this work, we report on the epitaxial growth of high-quality cubic indium oxide thick films on c-plane sapphire substrates using a two-step growth process. The epitaxial relationship of In2O3 on (0001) Al2O3 has been investigated. The (222) plane spacing and lattice parameter of a most strain-relaxed high-quality In2O3 film have been determined to be 292.58 pm and 1013.53 pm, respectively. The electronic properties in dependence of the film thickness are interpreted using a three-region model. The density at the surface and interface totals (3.3 +-1.5) x 10(13) cm(-2), while the background electron density in the bulk was determined to be (2.4+-0.5) x 10(18) cm(-3). Furthermore, post treatments such as irradiation via ultraviolet light and ozone oxidation have been found to influence only the surface layer, while the bulk electronic properties remain unchanged.en667621530journal article