title: ZnO nanowires hydrothermally grown on PET polymer substrates and their characteristics.
abstract: Zinc oxide nanowires (ZnO NWs) were successfully synthesized on the ITO/PET polymer substrates by a hydrothermal method. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy investigations were carried out to characterize the crystallinity, surface morphologies, and orientations of these NWs, respectively. The influence of NW surface morphologies on the optical and electrical properties of ZnO NWs was studied. The hydrothermally grown ZnO NWs with direct band gap of 3.21 eV emitted ultraviolet photoluminescence of 406 nm at room temperature. Field emission measurements revealed that the threshold electric fields (Eth, current density of 1 mA/cm2) of ZnO NWs/ITO/PET and ZnO NWs/ZnO/ITO/PET are 1.6 and 2.2 V/microm with the enhancement factors, beta values, of 3275 and 4502, respectively. Furthermore, the field emission performance of ZnO NWs deposited on the ITO/PET substrate can be enhanced by illumination with Eth of 1.3 V/microm and displays a maximum emission current density of 18 mA/cm2. The ZnO NWs successfully grown on polymer substrate with high transmittance, low threshold electric field, and high emission current density may be applied to a flexible field emission display in the future.
authors.affiliation: Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, Hsinchu 30050, Taiwan.
authors.forename: Chia Ying
authors.initials: CY
authors.lastname: Lee
authors.forename: Seu Yi
authors.initials: SY
authors.lastname: Li
authors.forename: Pang
authors.initials: P
authors.lastname: Lin
authors.forename: Tseung Yuen
authors.initials: TY
authors.lastname: Tseng
mesh_terms: D003460:Crystallization; D004563:Electrochemistry; D008027:Light; D049449:Luminescence; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D036103:Nanotechnology / Q000379:methods; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010777:Photochemistry; D017785:Photons; D011093:Polyethylene Terephthalates / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013379:Substrate Specificity; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014466:Ultraviolet Rays; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D011093:Polyethylene Terephthalates; D011108:Polymers; D015034:Zinc Oxide