ZnO films, doped with 2.9 atom% Cu, were prepared by radio frequency magnetron sputtering on sapphire substrate at different substrate temperatures. No magnetic impurities such as Fe, Co and Ni were found in the PIXE spectra. The ZnO:Cu films possessed the wurtzite ZnO structure. No precipitates such as CuO and Cu₂O or Cu cluster, were observed by synchrotron radiation X-ray diffraction in the ZnO:Cu films. Extended X-ray absorption fine structure (EXAFS) analysis showed that Cu atoms were incorporated into ZnO crystal lattice by occupying the sites of Zn atoms.