Abstract
High-quality ZnO epitaxial films have been grown by pulsed-laser deposition on Si (111) substrates using a nanothick high-k oxide Y <sub>2</sub> O <sub>3</sub> buffer layer. Determined by X-ray diffraction and transmission electron microscopy, the epitaxial relationship between ZnO and Y <sub>2</sub> O <sub>3</sub> follows (0001)<(21̄1̄0) <sub>ZnO</sub> ll(111)(101̄) <sub>Y2O3</sub> . ZnO lattice aligns with the hexagonal O sublattice in Y <sub>2</sub> O <sub>3</sub> and_the interfacial structure can be well described by domain matching epitaxy with 7 or 8 ZnO {1120} planes matching 6 or 7 {440} planes of Y <sub>2</sub> O <sub>3</sub> and lead to a significant reduction of residual strain. Superior optical properties were obtained even for ZnO films as thin as 0.21 μ from photoluminescence results. © 2009 American Chemical Society.