An experimental study of Cu diffusion in bulk ZnO single crystals at 1012 to 1220C was presented. Concentration profiles of substitutional Cu were determined by IR absorption at 5817/cm. The findings revealed that Cu in ZnO diffused faster than previously reported (Müller & Helbig, 1971). The discrepancy was tentatively explained by the formation of Cu complexes, which occurred at high Cu concentrations.

On Diffusion of Cu in ZnO. Herklotz, F., Lavrov, E.V., Weber, J.: Physica B, 2009, 404[23-24], 4807-9