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Abstract: We have developed a range of single and multilayer transparent conducting coatings consisting of three to five alternating layers of Al-doped ZnO (AZO) and metals using E-beam evaporation method. The prepared optimized coatings show excellent optical and electrical properties, improved thermal and long-term stability. Optimum thickness of metal and AZO layers was determined for high optical transmittance and good electrical conductivity. X-ray diffraction, spectrophotometer, atomic-force microscopy, scanning electron microscopy and four-point probe were used to explore the possible changes in electrical and optical properties. It was found that the multilayer coatings consisting of Al-doped ZnO and Ag metal show satisfactory properties of low resistance of 5Ω/sq, high transmittance of 90% and thermal stability up to 500°C. [Copyright &y& Elsevier]

Abstract: Indium molybdenum oxide (IMO) films were made from an oxidized target with In2O3 and MoO3 in a weight proportion of 95:5 by using a high density plasma evaporation (HDPE). Hydrogen was added to the Ar+O2 gas mixture during the preparation of the IMO films. With hydrogen, the decrease in the resistivity and the broadening of the process window was mainly due to an apparent increase in the mobility. The transmittance in the visible spectral range of IMO films deteriorated with the incorporation of hydrogen. Mo+6/Mo+4 species, –OH fragment, metallic Mo and Mo–O oxides in the film were suggested to affect its electrical and optical properties. Applications as transparent and conducting films for opto-electronic and telecommunication devices would be expected in the near future. [Copyright &y& Elsevier]

In this study, the ZnO films were deposited to different thicknesses by r.f. magnetron sputtering. X-Ray diffraction and pole-figure analysis were used to study the crystallinity and crystal orientation. The results showed that ZnO films deposited to a thickness below 500 nm were polycrystalline with a c-axis preferential orientation. However, ZnO films, 500 or 600 nm in thickness, exhibited good self-texture. The optical properties of ZnO films did not depend significantly on the crystallographic orientation or degree of texturing. They were mainly affected by the grain size and carrier concentration. [Copyright &y& Elsevier]

ZnO thin films were prepared by r.f. magnetron sputtering from a zinc oxide target. The effects of r.f. power and substrate temperature on the properties of ZnO films were studied. The composition of ZnO films was analyzed by X-ray photoemission spectroscopy. The Zn atomic composition in the films was higher than the O atomic composition at any r.f. power and growth temperature conditions. This behavior might be explained by the preferential sputtering of zinc atoms rather than oxygen atoms in the ceramic target. In this study, ZnO films with epitaxial grain growth had a preferred (0 0 2) orientation. The crystallographic orientation and the piezoelectric properties of ZnO films were influenced by the sputtering parameters. A good condition exists for making the c-axis oriented films in the range of deposition rate and substrate temperature under the experimental conditions in this study. ZnO films showed different surface morphologies and surface roughness under different deposition conditions. ZnO films were transparent in the visible region, but had obvious absorption in the UV region. There were no obvious changes in the optical properties of ZnO films by varying the r.f. power and substrate temperature in this study. The phase velocity in this study was relatively higher at the optimal r.f. power and substrate temperature. [Copyright &y& Elsevier]

Abstract: A layer of silver was deposited onto the surface of glass substrates, coated with AZO (Al-doped ZnO), to form Ag/AZO film structures, using e-beam evaporation techniques. The electrical and optical properties of AZO, Ag and Ag/AZO film structures were studied. The deposition of Ag layer on the surface of AZO films resulted in lowering the effective electrical resistivity with a slight reduction of their optical transmittance. Ag (11nm)/AZO (25nm) film structure, with an accuracy of ±0.5nm for the thickness shows a sheet resistance as low as 5.6±0.5Ω/sq and a transmittance of about 66±2%. A coating consisting of AZO (25nm)/Ag (11nm)/AZO (25nm) trilayer structure, exhibits a resistance of 7.7±0.5Ω/sq and a high transmittance of 85±2%. The coatings have satisfactory properties of low resistance, high transmittance and highest figure of merit for application in optoelectronics devices including flat displays, thin films transistors and solar cells as transparent conductive electrodes. [Copyright &y& Elsevier]

Near-infrared (NIR) shielding properties are important for solar films. In this study, Cs x WO 3 films prepared using electron beam evaporation were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, and spectrophotometry. The effects of annealing on NIR shielding properties and film microstructure were investigated. The results show that the NIR shielding properties of Cs x WO 3 films can be improved by annealing at 300–450 °C under pure H 2 atmosphere, the amorphous thin films being transformed to crystalline films. The Cs x WO 3 films annealed at 450 °C in pure H 2 atmosphere showed high transmittance of visible light (70%) and high NIR shielding ratio (99%). [ABSTRACT FROM AUTHOR]

Abstract: Sb/SnO2 bi-layer films were prepared using ion beam sputtering deposition (IBSD) and radio frequency (RF) magnetron sputtering deposition. The optimal parameters of SnO2 thin films were found to be dependent on the processing conditions of vacuum pressure and flow ratio of O2/(O2 +Ar). The as deposited bi-layer films were treated by ex situ pulsed ultraviolet laser beam at 355nm for the assistance of Sb-ion with SnO2 interface. This paper takes a closer look at the characteristics of the laser irradiation effect of Sb/SnO2 bi-layer films on the optical and electrical behavior and the interface microstructure of Sb/SnO2 by high resolution transmission electron microscopy (HR-TEM). After UV pulse laser irradiation of bi-layer films, crystalline Sb between amorphous Sb and SnO2 nanocrystalline thin films was observed. [Copyright &y& Elsevier]

Abstract: Multilayer coatings consisting of thin silver layers sandwiched between layers of transparent conducting metal oxides are investigated from the view point of low-resistance electrodes for use in flat panel displays, solar cells, etc. ZnO/Ag/ZnO multilayer films were prepared on glass substrates by simultaneous RF magnetron sputtering of ZnO and dc magnetron sputtering of Ag. Optimization of the deposition conditions of both ZnO layers and metallic layers were performed for better electrical and optical properties. The structural, electrical and optical properties of the films (deposited at room temperature, different substrate temperature and annealed at different conditions) were characterized with various techniques. We could not produce high-quality transparent conductive electrodes simply by annealing at various temperatures. However, improved electrical properties and a considerable shift in the transmittance curves was observed after heat treatment. The experimental results show that the electrical resistivity of as-grown films can be decreased to 10−5 Ω cm level with post-annealing at 400 °C for 2 h in vacuum atmosphere. After heat treatment, the sheet resistance was reduced as much as 20% which was due to the increased grain size of Ag film. The samples heat treated at 200–400 °C under vacuum or nitrogen atmosphere showed the best electrical properties. The key to the superior electrical and optical properties of the multilayer is the optimization of growth conditions of the silver layer by careful control of the oxide properties and the use of appropriate annealing temperature and atmosphere. [Copyright &y& Elsevier]