Microphotoluminescence study of individual suspended ZnO nanowires

We report microphotoluminescence measurements on individually suspended ZnO nanowires attached to nanometer-sized metal tips. This procedure avoids the possible influence of the substrate and enables comprehensive optical, electrical, chemical, and morphological characterizations to be carried on the same individual nanowire. Based on the ZnO nanowires examined, we found that the near band edge emission redshifted with the increasing intensity of the defect-related green emission. The comprehensive characterizations of in situ heated ZnO nanowires suggested a correlation between the defect green emission and the oxygen deficiency, which also affect the carrier density, and thus, the nanowire's transport property. (C) 2008 American Institute of Physics.