Investigation on the origin of green light emission in ZnO bulk materials

ZnO bulk materials were implanted by O and Zn with different concentration and their photoluminescence (PL) properties were investigated in detail. The results clearly show that O and Zn implantation indeed have great influence on the green light emission. By comparing the PL spectra for the samples with different implantations, Oi, Zni and Cu-related defects have been excluded from the possibility of the origin of green light emission step by step. Finally, it can be concluded that VZn is responsible to the observed green light emission, which has good agreement with the theoretical results from first principle calculation.