ZnO growth on yttria-stabilized zirconia (YSZ) (I 1 1) single-crystal substrate has been carried out by metalorganic chemical vapor deposition (MOCVD). High-quality epitaxial ZnO has been evidenced by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Cross-sectional TEM from all deposited films reveals that the interface between ZnO and YSZ is atomically flat, and orientation relationship is deduced to be [1 (1) over bar 100](ZnO//)[11 (2) over bar](YSZ,) (2 (1) over bar(1) over bar0)(ZnO)//[001](YSZ) and (0 0 0 2)(ZnO)//(111)(YSZ). It has been found that surface roughness increases with the substrate temperature in the range of 500-700 degrees C. The growth rate also varies with the temperature. (c) 2006 Elsevier B.V. All rights reserved.