Investigation on Hydrothermal Growth of a-Plane ZnO Using Epitaxial Lateral Overgrowth

The growth mechanism and the crystallinity of hydrothermally synthesized nonpolar a-plane ZnO (a-ZnO) on a-plane GaN template were investigated by using epitaxial lateral overgrowth (ELO) patterns parallel or perpendicular to the c-axis direction. Due to the anisotropic growth rates along the specific crystallographic directions, lateral overgrowth of a-ZnO was observed only for ZnO grown on the ELO stripe patterns perpendicular to the c-axis direction. In X-ray diffraction analysis, a-ZnO grown on the c-axis parallel patterns had smaller FWHM values of the X-ray rocking curves along the X-ray in-beam orientations in the c- and the m-axis