Photoluminescence Spectra of ZnO Films Doped with Li and Cl Atoms

ZnO films doped with Li and Cl atoms have been prepared by organometallic chemical vapor deposition method. In photoluminescence spectra of the doped ZnO films, strong emission appears at 376 nm which is slightly longer than that of free-excitons. As excitation intensity increases, a peak wavelength of the emission is shifted toward a shorter value. The emission near band-gap edge is assigned to radiative recombination via Li-Cl pairs.