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Nanostructures are the building blocks of future nanodevices and thus methods for fabricating nanostructures of various materials in various forms are fundamentally important. Among those nanostructures ZnO has received much attention over the past few years due to the wide range of research by many different groups focused on different novel nanostructures with different properties. Although ZnO nanowires have been intensively studied, there are only a few methods that showed promising characteristics for practical applications. Without much effort, it can be grown in many different nanostructure forms, thus allowing various novel devices to be achieved. In this study, we intend to review those methods that enable nanostructure growth to be more controllable and feasible for applications. The methods for fabricating ZnO nanostructures are introduced in the first part. In the second part, the application of those nanostructures are mentioned and explained. Finally, the future realization of nanodevices is discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this work, indium (In) doped ZnO nanowires are grown on a Si substrate by chemical vapor deposition (CVD), at a relatively low temperature of 550°C. The effects of In concentration on the morphology, microstructure, luminescence and electrical properties of ZnO nanowires are investigated. The diameters and lengths of these nanowires are in the ranges of 70–311nm and 10–15μm, respectively. These nanowires are single crystals growing in the [0001] direction. The maximum solubility of In in ZnO is estimated to be 3.47at.%. Photoluminescence (PL) spectra reveal a red shift in the ultraviolet emission and intensity enhancement in the green emission with increasing indium doping concentration. Besides, carrier concentration, mobility and resistivity of the nanowires with different doping concentrations are determined based on single-nanowire field effect transistors (FET). [Copyright &y& Elsevier]

We demonstrate a novel defect-induced bending mechanism for a modified oblique-angle deposition (OAD) system, where different defect density was introduced to accommodate the mass difference between the shadowed and exposed surfaces, leading to continuous structural bending. Oblique angle sputtering and hydrothermal processes were employed for growth of inclined ZnO nanowire arrays on ZnO bent columns. Transmission electron microscopy images reveal that a dislocation network was introduced to accommodate the mass difference in bent columns, and the bending angle could be controlled by growth temperature. Nanowires were then grown along the tangent lines of the bent column tips. The bent column curvature and limited space determine the nanowire growth direction. The reflectance measurements demonstrate that the oblique-aligned ZnO nanowire arrays are an excellent candidate for antireflection coatings, showing the significant suppression of reflectance of 87.5% and 90.0% for polished Si under TE and TM polarization, respectively. The interference oscillations of reflectance show the optical anisotropy of oblique-aligned ZnO nanowire arrays, which is dependent on the angle range of nanowire direction. Dislocation networks were introduced to accommodate strain in bent columns during oblique-angle deposition under highly energetic conditions, which made columns bent to opposite quadrants, with the bending angle controlled by growth temperature. Oblique-aligned nanowires grown on these bent columns exhibit excellent antireflection properties. [ABSTRACT FROM AUTHOR]