The epitaxial growth of ZnO nanowires for optical devices by a modified thermal evaporation method

The epitaxial growth of ZnO nanowires over ZnO thin film deposited on silicon substrates was carried out using a modified thermal evaporation method. The precursor, which consisted of 10–30 wt.% zinc nitrate loaded over activated carbon, was prepared specifically for this study. The loading amount of zinc nitrate was varied to control the length and diameter of the ZnO nanowires. X-ray diffraction patterns confirmed that the ZnO nanowires grown on the silicon substrates were composed of typical single-crystalline ZnO. The single-crystal ZnO nanowires synthesized in this study were also studied by photoluminescence spectroscopy, and emitted intense blue UV light at around 380 nm.