Effects of Annealing on the Structural and Photoluminescent Properties of Ag-Doped ZnO Nanowires Prepared by Ion Implantation

Abstract

ZnO nanowires deposited on Si substrates were prepared by thermal evaporation of a mixture of ZnO and carbon powder. Ag ions with an energy of 63 keV and a dose of 5 × 1015 ions/cm2 were implanted into the as-prepared ZnO nanowires. After ion implantation, the Ag-implanted ZnO nanowires were annealed in air at different temperatures from 600°C to 1000°C. Effects of ion implantation and thermal annealing on the structural and photoluminescent (PL) properties of the ZnO nanowires were investigated by transmission electron microscopy (TEM), selected area energy dispersive X-ray spectroscopy (SAEDX), X-ray diffraction (XRD), and fluorescence spectrophotometry. TEM, HR-TEM, and SAEDX analyses demonstrated that efficient doping of Ag was achieved by ion implantation and the subsequent annealing process. XRD patterns revealed that the hexagonal wurtzite structure of ZnO nanowires was maintained after ion implantation. Photoluminescent emissions of ZnO nanowires were decreased significantly by Ag implantation but could be recovered by thermal annealing. The mechanism of the influence of ion implantation and annealing on the PL intensity was assessed.