SURFACE-STRUCTURE OF SINGLE-CRYSTAL CEO2 LAYERS GROWN ON SI

The surface morphology of epitaxially grown CeO2 layers on Si(100) and Si(111) substrates was studied using atomic force microscopy (AFM) an d transmission electron microscopy. It was found that the CeO2(111)/Si (111) surface has a triangular-pyramidal hillock structure consisting of three (111) facets. In contrast, the CeO2 layer grown on Si(100) ha s (110) orientation and a periodically corrugated structure with gable roof shaped stripes consisting of two (111) facets. Quantitative anal yses of AFM data reveal that as the layer thickness increases, the sur face structure grows in size: the surface roughness increases monotoni cally for CeO2(111), whereas it saturates for CeO2(110).