Orientation Dependent Epitaxial Growth of CeO2 Layers on Si Substrates

Abstract

ABSTRACTCerium dioxide (CeO2) layers epitaxially grown on (100), (111) and (110) silicon substrates by electron beam evaporation in an ultra-high vacuum were investigated. CeO2 layers on Si (111) substrates were proved to be epitaxially grown at the substrate temperature above 200°C, and had considerably good crystalline quality. On the other hand, CeO2 layers grown on Si (100) at 800°C consisted of more than 98% volume fraction of (110) component. Cross-sectional high resolution transmission electron microscopy and selected area electron diffraction verified clearly the above crystallography orientation and that the <100> direction in the CeO2(110) plane was parallel with the <110> direction in the Si (100) plane. The cross-sectional lattice image confirmed the existence of ∼ 6 nm-thick intermediate amorphous layer between the CeO2 layer and the Si substrate.