Luminescence in Cu-implanted ZnO thin films

New ion implantation techniques were used to study phenomena related to emission in ZnO thin films implanted with Cu. Room temperature Cu implantation was at 125 keV, in a Cu dose range of 1 1012 to 2 1014 ions/cm2. The intensity of bandedge emission was continuously decreased with increasing Cu dose because of implantation-induced damage. After annealing the films at 800 8C for 3 h, we observed luminescence in the visible region; this was enabled by recovery from the implantation damage and the Cu phosphor. Emission at about 555 nm was observed in the Cu dose range from 1 1012 to 2 1014 ions/cm2.