The lattice location of Cu in single-crystalline zinc oxide was studied by means of the emission channelling technique. Following 60keV room-temperature implantation at a fluence of 2.3 x 1013/cm2, the angular distribution of β-particles emitted by the radioactive isotope 67Cu was measured by using a position-sensitive detector. The β-emission patterns gave direct evidence that, in the as-implanted state, a large fraction of Cu atoms (60 to 70%) occupies almost ideal substitutional Zn sites with root-mean-square displacements of 0.16 to 0.17Å. However, following annealing at 600C and above Cu was found to be located on sites that were characterized by large root-mean-square displacements (0.3 to 0.5Å) from Zn sites.

Lattice Location and Stability of Implanted Cu in ZnO. Wahl, U., Rita, E., Correia, J.G., Alves, E., Soares, J.G.: Physical Review B, 2004, 69[1], 012102