Structural, Optical and Electrical Properties of Nitrogen Ion Implanted ZnO Nanorods

This study examined the micro-structural and electrical properties of N⁺-ion-implanted ZnO nanorods. Nitrogen ions with energies of 10–90 keV and beam fluxes of 10¹³–10¹⁶ ions/cm² were implanted on vertically-aligned ZnO nanorods. Energy dispersive X-ray spectroscopy measurements showed that N⁺ ions were spread uniformly over the nanorods. Extended X-ray absorption fine structure measurements revealed that the implanted N⁺s had partially substituted for the oxygen sites. Photoluminescence measurements showed a neutral-donor bound exciton peak at 3.36 eV and a two-electron-satellite peak at 3.33 eV independent of the ion energy and flux. The I–V characteristic curves showed that the current density was not changed by the N⁺ ion energy and flux much. These results strongly suggested that the N ions substituted for the oxygen sites were neutral.