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Zinc Oxide Thin Films (zinc + oxide_thin_film)

Distribution by Scientific Domains
Polymers and Materials Science50%

Selected Abstracts

Effects of Individual Layer Thickness on the Microstructure and Optoelectronic Properties of Sol,Gel-Derived Zinc Oxide Thin Films

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2008
Noureddine Bel Hadj Tahar
Zinc oxide (ZnO) thin films were prepared under different conditions on glass substrates using a sol,gel process. The microstructure of ZnO films was investigated by means of diffraction analysis, and plan-view and cross-sectional scanning electron microscopy. It was found that the preparation conditions strongly affected the structure and the optoelectronic properties of the films. A structural evolution in morphology from spherical to columnar growth was observed. The crystallinity of the films was improved and columnar film growth became more dominant as the zinc concentration and the substrate withdrawal speed decreased. The individual layer thickness for layer-by-layer homoepitaxy growth that resulted in columnar grains was <20 nm. The grain columns are grown through the entire film with a nearly unchanged lateral dimension through the full film thickness. The columnar ZnO grains are c -axis oriented perpendicular to the interface and possess a polycrystalline structure. Optical transmittance up to 90% in the visible range and electrical resistivity as low as 6.8 × 10,3·,·cm were obtained under optimal deposition conditions. [source]

Preparation of ZnO thin film by the sol,gel method using low temperature ozone oxidation

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 7 2010
Takashi Ehara
Abstract Zinc oxide thin films have been prepared by the sol,gel method from a 2-methoxyethanol solution of zinc acetate dihydrate on SiO2 substrates using air, pure oxygen, and 1% ozone in oxygen as oxygen source. In the cases where air or oxygen was used as the oxygen source for thermal annealing, samples annealed at 600 to 800,°C exhibit a (0002) peak in X-ray diffraction (XRD). A sample annealed at 700,°C exhibited the highest (0002) peak intensity in conventional thermal annealing. However, the case using 1% ozone in oxygen as the atmosphere presented different results. A sample treated in 1% ozone at 100,°C had peak intensity in XRD (0002) comparable with samples annealed at several hundreds of degree in air or oxygen. This result indicates that the high oxidation efficiency of ozone is useful in decreasing the processing temperature of the sol,gel method. [source]

Influence of annealing temperature on the structural and optical properties of sol,gel prepared ZnO thin films

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 10 2006
Mingsong Wang
Abstract Zinc oxide thin films have been prepared via a sol,gel process. The influence of annealing temperature on the structural and optical properties of the ZnO thin films has been investigated. The prepared ZnO thin films had a polycrystalline hexagonal wurtzite structure with no preferred orientation. The annealing temperature had a great effect on the optical properties of the ZnO thin films: the optical band gap became narrow due to the increase in crystallite size and the reduction in amorphous phase amount with increasing annealing temperature. Absorption or desorption of oxygen in the annealing process caused the observed yellow or green emission. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Flux of Positive Ions and Film Growth in Reactive Sputtering of Al-Doped ZnO Thin Films

PLASMA PROCESSES AND POLYMERS, Issue S1 2007
Florian Ruske
Abstract The reactive magnetron sputtering deposition of Al-doped zinc oxide thin films using a dual magnetron has been studied for a flux of positive ions and the total thermal load onto the substrate. The spatial distribution of both quantities has been studied using a thermal probe and a retarding field analyzer mounted onto a moveable carrier system. The positive ions were found to mostly originate from the plasma sheath at the substrate, with the spatial distribution determined by the plasma density distribution in the coating chamber. The total energy flux to the substrate mainly originated from the plasma, with positive ions only contributing a small part of the total plasma irradiation. In the tested conditions and with the coater examined, the quality of the deposited films mainly depends on oxygen distribution on the substrate and is not a direct consequence of the total energy flux to the substrate. [source]