"ZnO-based nanostructures," Chapter 4 in Handbook of Zinc Oxide and Related Materials: Volume Two, Devices and Nano-Engineering

Abstract

This chapter discusses the transport mechanism and surface-related transport properties of zinc oxide (ZnO) nanostructures, with particular interest in reports of the mobility exceeding state-of-the-art planar devices observed in ZnO nanowire (NW) devices. Most of ZnO nanostructures are grown with the three main methods: vapor–liquid–solid (VLS) process, solution-based chemical synthesis, and chemical vapor deposition. ZnO nanostructures synthesized by VLS processes are produced through the crystallization from the alloys at their supersaturated states. Solution-based chemical synthesis is also referred as the hydrothermal method. Photoluminescence analysis is the most widely applied technique to investigate optical properties of ZnO nanostructures, since it can estimate the tightly bound excitons, the bandgap energy, and related defect transitions of ZnO. Polarized photodetection of both ultraviolet and visible light shows that the photoconductivity of ZnO NW is maximized when incident light is polarized parallel to the NW axis.