Epitaxial ZnO film has been grown using an epi-GaN buffer layer on sapphire (0001) substrate by sol-gel technique. The 20 curve full width at half maximum of the ZnO (0002) peak for the film annealed at optimized temperature of 600 degrees C, was found to be 0.07 degrees from X-ray diffraction spectrum. The atomic force microscopy revealed smooth hexagonal faceting of the ZnO films. Photoluminescence spectrum at room temperature exhibits a sharp exciton emission with a line width of 120 meV with negligible deep level emission. The observed six fold symmetry in reflection high energy electron diffraction pattern confirms the epitaxial nature of the ZnO film. (c) 2006 Elsevier B.V. All rights reserved.