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In this paper, the effect of nitrogen flow rates on the physical properties of thin TaN films deposited on glass and silicon substrates using reactive DC magnetron sputtering was experimentally studied. The structural and optical properties of the films were evaluated by X-ray diffraction, atomic force microscopy, and optical spectrophotometry. X-ray diffraction patterns revealed that the phase composition evolves from pure metallic δ-Ta body centred cubic to tantalum nitride δ-TaN rock-salt structure. However, when the N2 flow rate exceeds 2 sccm, the films will show a poorly defined crystallization composed of mixture of fcc TaN phase and amorphous phases. Scanning electron microscopy and atomic force microscopy images revealed that the films deposited at high nitrogen flow rate possess smooth surface, good quality and lower roughness. The optical characterisation confirms that they are two groups of samples. The first have an metallic character with high reflectance and the second group are more transparent with an dielectric character with an absorption gap around 1.8 eV. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis, crystal structure, surface morphology, optical and electrical properties of Mgdoped Sn2S3 thin films deposited by spray pyrolysis technique. All the films exhibit orthorhombic crystal structure with a (211) preferential orientation. Crystallite size calculations based on the Debye-Scherrer formula indicated that the Sn2S3 crystallite size increases with Mg content from 27.97 nm to 33.58 nm. Scanning electron microscopy images showed that all the films were very smooth composed of nanoneedle and nanoplate shaped grains. The band gap energy of the films exhibits a blue shift from 1.94 eV to 2.09 eV with increase in Mg concentration. Resistivity values of the undoped and Mg-doped Sn2S3 films were found to be in the order of 0.1 Ω cm. From the obtained results it is observed that the Sn2S3 film coated with 2 wt% Mg concentration exhibits better physical properties. [ABSTRACT FROM AUTHOR]

This paper presents the results of the structural, morphological and optical analysis of In:CdS thin films prepared by chemical bath deposition and successive ionic layer adsorption and reaction techniques. X-ray diffraction patterns showed the hexagonal phase of cadmium sulfide and it has been found that the amount of atomic percentage of indium increases the intensity of the preferential orientation (002) plane in chemical bath deposition In:CdS thin films. Compositional analysis confirmed the replacement of Cd ions by In ions and morphological analysis confirmed the lesser grain size and dense morphology in chemical bath deposition In:CdS thin films. Increase in In concentration in successive ionic layer adsorption and reaction In:CdS thin films leads to an increase in the optical transmission up to 80% and the higher band gap and therefore the results of this investigation enabled to understand the significance of preparation technique. [ABSTRACT FROM AUTHOR]

In this work, we study the physical properties of hybrid organic/inorganic mixture semiconducting layers. Materials selected for the research were poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4- b0]dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] and nanostructured cadmium sulfide (CdS) powder. These materials have been chosen due to their narrow optical band gap combined with high chargecarrier mobility, which makes them interesting for application as components of active layers in bulk p-n heterojunctions. In particular, we present the results of studies on the influence of CdS content on the physical properties of thin hybrid films. The ellipsometric measurements showed that the composition of the base layers influenced their optical properties without significantly influencing their thermal stability. [ABSTRACT FROM AUTHOR]

Ba-doped TiO2 thin films were deposited onto glass substrates by sol-gel spin-coating method and annealed at 550°C for 2 h. The effect of barium doping on the structural, morphological, optical, and photocatalytic properties of TiO2 thin films was investigated. X-ray diffraction analysis revealed that all films crystallize in the anatase phase with the plane (101) as preferential orientation. As a result of the Ba doping, the crystallite size decreased from 19 to 9 nm. The surface morphology and roughness of TiO2 were shown to be affected by Ba doping content using atomic force microscopy. As Ba content increased, the optical transmittance of the films increased to over 85% in the visible region and the gap energy increased from 3.42 to 3.77 eV. Doping by barium enhances the photocatalytic activity of TiO2 film for degradation of rhodamine B under UV light irradiation, and the best performance was found for 3% of Ba:TiO2 film. [ABSTRACT FROM AUTHOR]

Ge25Se75 binary glass is prepared using melt-quenching technique. Thin films of 250 nm Ge25Se75 are thus evaporated using thermal evaporation method on a cleaned glass substrate. Energy dispersive X-ray analysis confirmed the starting percentage of the element. The effect of microwave irradiation on Ge25Se75 thin film with different illumination times (0–90 min) is studied. As confirmed by X-ray diffraction and scanning electron microscopy measurements, the nature of the as-prepared Ge25Se75 thin films appears to be amorphous. The type of optical transition has been demonstrated to be allowed indirect transitions. Moreover, the rest of the optical parameters have changed as a result of the microwave irradiation. It can be observed that, for Ge25Se75 thin films, the optical band gap increases as the illumination time increases. In terms of bond adjustments and changes in these films’ microstructure, this post-light increment in the band gap was decoded. Furthermore, while increasing the illumination time of microwave irradiation, the dispersion parameters of Ge25Se75 films were diminished. [ABSTRACT FROM AUTHOR]

Three kinds of precursor thin films with stacking orders of Cu/Sn/ZnS, Cu/Sn/ZnS/Cu/Sn/ZnS and Cu/Sn/ZnS/Cu/Sn/ZnS/Cu/Sn/ZnS were prepared by magnetron sputtering and annealed with sulfur powder. The microstructure, morphology and optical properties of thin films were investigated by X-ray diffraction, the Raman scattering, scanning electron microscopy and UV-visible spectrophotometer. The increase of cycle number decreases the sulfurizing temperature of the formation of Cu2ZnSnS4 phase. Chemical composition can be controlled by cycle sputtering deposition. After sulfurizing at 500 °C, the particle size and the band gap increase with increasing cycle number. [ABSTRACT FROM AUTHOR]

The optical properties of lead oxide samples prepared using thermal evaporation technique on unheated glass substrates with different film thicknesses have been studied. The structural characteristics of a lead oxide sample was investigated using X-ray diffraction and it is confirmed to be in the amorphous state. The optical properties of the prepared films were studied by transmittance and reflectance measurements, and the integrated transmittance (TUV, TVIS and TSol) in ultraviolet, visible and solar regions was calculated and found to be affected by film thickness. The dependence of absorption coeficient on wavelength was also reported. The energy gap was calculated and has been observed around 3.7 eV. [ABSTRACT FROM AUTHOR]

In this work structural and optical properties of TiO2 thin films doped with different amount of Nd have been outlined. The result have shown that by quantity of Nd amount in the film dense nanocrystalline or amorphous thin films were obtained. [ABSTRACT FROM AUTHOR]

In this work, investigations of structural, optical and electrical properties of transparent oxide semiconductor thin films based on TiO2 doped with Eu, Pd and Tb, Pd have been presented. The transparent oxide semiconductor nanocrystalline thin films were prepared by magnetron sputtering process. It was shown that doping with selected elements results in semiconducting properties of prepared thin films of oxides with p-(TiO2:(Tb, Pd)) or n-type (TiO2:(Eu, Pd)) of electrical conduction. [ABSTRACT FROM AUTHOR]