Growth, Characterization, and Polarity Identification of (0001) Zn1 − xMgxO Epitaxial Films on Lattice-Matched β-LiGaO2 (001) Substrates

Abstract

Small lattice-mismatched (001) substrates have been used for the epitaxial growth of (0001) films using the metallorganic chemical vapor deposition method. Structure characterizations by employing X-ray diffraction and transmission electron microscope demonstrate that no MgO or Mg cluster exists throughout the films. The epitaxial (0001) films are successfully grown on the (001) substrates with the epitaxial relationship of and . Polarity of the films is determined by the convergent beam electron diffraction technique as well as wet chemical etching. Both results indicate the Zn-polarity of films. The room-temperature cathodoluminescence spectra of the epitaxial (0001) films show an obvious blueshift of the near-bandedge emission with increasing Mg content, suggesting a successful bandgap engineering in the epitaxial (0001) films on the (001) substrates.