Diameter‐ and density‐controlled synthesis of well‐aligned ZnO nanowire arrays and their properties using a thermal evaporation technique

Abstract

Abstract Vertically well‐aligned ZnO nanowire (NW) arrays were synthesized directly on Si(100) substrate without any metal catalysts by conventional thermal evaporation. The effects of the substrate positions on the structures and properties of ZnO NW arrays were primarily discussed. The orientation and morphology of the resultant NWs were analyzed by using X‐ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results showed that the density and diameter of the ZnO NWs can be effectively controlled by changing the substrate position. The photoluminescence (PL) characteristics of the grown ZnO NW arrays show a sharp and strong ultraviolet (UV) emission at 380 nm and a very weak green emission at around 490 nm, indicating that the as‐synthesized NWs have outstanding optical properties with good crystalline quality and may have excellent application potential in optoelectronic devices.