A photoluminescence study was made of Zn-diffused and annealed material. A new peak was found near to 1.33eV. After annealing, the peak energy of the luminescence shifted towards higher energies. This reflected the out-diffusion of Zn. By depth profiling of this luminescence it was deduced that recombination, due to the interstitial Zn donor, predominated near to the surface.

J.S.Choi, H.J.Lim, J.I.Lee, S.K.Chang, H.L.Park: Physica Status Solidi B, 1991, 164[2], K69-72