High quality epitaxial layers of monocrystalline oxide materials (24) can be grown overlying monocrystalline substrates (22) such as large silicon wafers. The monocrystalline oxide layer (24) comprises a layer of monocrystalline oxide spaced apart from the silicon wafer by an amorphous interface layer (28) of silicon oxide. The amorphous interface layer serves as a decoupling layer between the substrate and the buffer layer so that the substrate and the buffer is crystal-graphically, chemically, and dielectrically decoupled. In addition, high quality epitaxial accommodating buffer layers may be formed overlying vicinal substrates using a low pressure, low temperature, alkaline-earth metal-rich process.