a b s t r a c tThe polycrystalline CdTe films were deposited by the close-spaced vacuum evaporation at the different substrate temperatures (150-550 1C). The X-ray diffraction measurements of structural and substructural properties of these films were carried out to study their phase composition and texture. The films' parameters such as the coherent scattering domain size, microdeformation level and mean density of dislocations were determined based on the broadening of diffraction peaks. In this case the Hall and three-fold convolution approximations were used. Surface morphology, grain size and growth mechanism of the films were determined by the scanning electron microscopy. The low temperature photoluminescence measurements allowed us to establish the correlation between the point and extended defect structure on the one hand and the growth conditions on the other. As a result, the growth conditions of CdTe polycrystalline films with fairly good crystal and optical quality were determined.

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The effect of substrate temperature (Ts = 373–973 K) on the structural and optical properties of ZnS films obtained by a close‐spaced vacuum sublimation technique has been studied. Examination of layers morphology and structure was performed by scanning electron microscopy and X‐ray diffraction methods. The results of these studies enabled determination of the dependence of the main structural film parameters (texture, surface roughness, lattice parameters, grain and X‐ray scattering domain sizes, microstrain) on the growth conditions. Optical characteristics were studied in the range of wavelength near the “red edge” of ZnS photoconductivity. Spectral distributions of transmission coefficient T (λ), refractive index n (λ), extinction coefficient k (λ) and their dependence on the deposition temperature of ZnS films are obtained. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

In this work, we report on the structural and optical properties of ZnO films deposited by pulsed spray pyrolysis at relatively low temperatures, compatible with a large variety of substrates and processing technologies. Crystalline ZnO films were deposited onto glass substrates using zinc acetate dihydrate dissolved in distilled water with concentration of 0.2 M. The temperature of the substrate was varied in the range T s = 473-673 K with ΔТ = 50 K. Effect of T s were investigated by scanning electron microscopy, x-ray diffraction and energy dispersive x-ray, and optical spectroscopies. Also, the influence of T s on the grain size, phase composition, texture quality, coherent scattering domain size, crystal lattice parameters, chemical composition, transmission coefficient, and the bang gap of the ZnO films were studied. X-ray diffraction analysis revealed that films were polycrystalline with hexagonal phase and showed as preferential orientation (101) at T s < 573 K and (100) and (002) at T s > 573 K. Scanning electron microscopy (SEM) measurements showed that the substrate temperature has a strong effect on morphology of the films. Energy dispersive analysis revealed that ZnO films consisted of the non-stoichiometric compounds. Optical measurements showed ZnO films to be highly transparent in the visible region, and optical band gap is shifting from 3.18 eV to 3.30 eV.

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