High quality epitaxial ZnO films on sapphire (110) plane have been fabricated on ZnO homo-buffer layers crystallized via solid-phase epitaxially (SPE). The SPE-ZnO films are fabricated by annealing of amorphous ZnON (a-ZnON) films deposited by RF magnetron sputtering. During annealing, the a-ZnON films are oxidized and converted to ZnO crystal. X-ray diffraction (XRD) analysis shows that the resultant films are epitaxially grown on the sapphire substrates. By using the SPE-ZnO films as homo-buffer layers, the ZnO films with high crystallinity, which are deposited by RF magnetron sputtering, are fabricated. The full width at half-maximum of XRD patterns for 20-omega and omega scan of (002) plane are 0.094 degrees and 0.12 degrees, respectively, being significantly small compared with 0.24 degrees and 0.55 degrees for the films without buffer layers. Thus utilizing SPE buffer layers is very promising to obtain epitaxial ZnO films with high crystallinity. (C) 2011 Elsevier B.V. All rights reserved.