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The influence of the thickness on the optical, structural and morphological properties of CdS thin films elaborated by chemical bath deposition is studied. The deposition time varies between 15 and 75 min and the optical measurements show that the films have high optical transmission (85%). The band gap presents a maximum of 2.44 eV for a deposition time of 30 min which corresponds to a lower disorder. The deposition rate ( n type conductivity with a flat band potential of −0.95 V SCE and an electron density of 1.43×10 25 m −3 . The Nyquist plot shows the predominant contribution of the grain boundaries; the data are modeled to an equivalent circuit with a constant phase element. As application, orange II is oxidized via radicals and the best photoactivity is obtained at pH~7. 68% of orange II disappears in ~1 h under solar light (AM 1). The oxidation follows a zero order kinetic with a rate constant of 0.11 mol L −1 min −1 .

We present the influence of Fe-doping (2%, 3% and 4%) on ZnO thin films. For this purpose, structural, electrical and optical proprieties have been investigated by X-ray diffraction, 4-points technique and UV-Visible spectrophotometry. The ZnO:Fe thin films have been deposited by pneumatic spray pyrolysis on glass substrates at different temperatures (350, 400 and 450°C) and fixed molarity (0.1mol/l). The precursor solution is a mixture of zinc acetate dihydrate (Zn(CH3COO)2, 2H2O) and iron (...)

Cubic cadmium sulphide (CdS) thin films with (111) preferential orientation were prepared by chemical bath deposition (CBD) technique, using the reaction between NH 4 OH, CdSO 4 and CS(NH 2 ) 2 . The films properties have been investigated as a function of bath temperature and deposition time. Structural properties of the obtained films were studied by X-ray diffraction analysis. The structural parameters such as crystallite size have been evaluated. The transmission spectra, recorded in the UV visible range reveal a relatively high transmission coefficient (70%) in the obtained films. The transmittance data analysis indicates that the optical band gap is closely related to the deposition conditions, a direct band gap ranging from 2.0 eV to 2.34 eV was deduced. The electrical characterization shows that CdS films' dark conductivities can be controlled either by the deposition time or the bath temperature.

The present work deals with the preparation and characterization of cadmium sulfur (CdS) thin films. These films are prepared by chemical bath deposition on the well cleaned glass substrates. The thickness of the samples was measured by using profilometer DEKTAK, structural and optical properties were studied by X-ray diffraction analysis, and UV-visible spectrophotometry. The optical properties of the films have been investigated as a function of temperature. The band gap energy and Urbach energy were also investigated as a function of temperature. From the transmittance data analysis the direct band gap ranges from 2.21 eV to 2.34 eV. A dependence of band gap on temperature has been observed and the possible raisons are discussed. Transmission spectra indicates a high transmission coefficient (75 %). Structural analysis revealed that the films showed cubic structure, and the crystallite size decreased at a higher deposition temperature.

In this work we report the structural, optical and electrical properties of CdS thin films prepared by chemical bath deposition (CBD) under the effect of solution temperatures. The solution temperatures used vary between 55 and 75 °C. The XRD patterns show that the films have a hexagonal phase with a preferential (002) orientation. The structural parameters such as the grain size, dislocation density and strain are calculated. The transmission spectra, recorded in the UV visible range, reveal a high transmission coefficient (85%) of the prepared films and an optical band gap values of 2 – 2.4 eV. The electrical measurements show that the dark conductivity values increase from 10−7 to 10−4 (Ω.cm)−1 at higher temperature (Ts > 65°C). It is found that the photoconductivity of the deposited films is two to five decades larger than the dark conductivity, and the photoconductivity to the dark conductivity ratio obtained at 3000 Lx vary from 102 to 105. From these results we inferred that the elaborated CdS thin films exhibit good properties intended for solar cell window layers.

This work deals with the preparation of cadmium sulfide (CdS) thin films by chemical bath deposition. The influence of the solution temperature is investigated in this study. We suggest that activation energy of the deposition rate measurement can be a tool for determining the nature of the deposition mechanism. We found that at low solution temperature, the growth mechanism proceeds via the ion by ion process, and found the corresponding activation energy equal to 0.06 eV. However, at higher solution temperature, the film deposition became via the cluster by cluster process, the growth rate activation energy is equal to 0.48 eV. The films' structural and optical properties were studied by x-ray diffraction analysis and UV–visible spectrophotometry. Structural analysis revealed that the deposited films have a cubic structure, and the crystallite size decreases with increasing deposition temperature. The transmission spectra of the film, in the visible range, show a high transmission coefficient (70%). The transmittance data analysis indicates that the optical band gap is closely related to the solution temperature. From this analysis, a direct band gap ranging from 2.21 to 2.34 eV was deduced. From the electrical characterization we inferred that CdS films are n-type and their dark conductivities reduced with increasing bath solution temperature. From the photoconductivity measurements we concluded that films deposited at low temperatures (less than 60 °C) or high temperatures (higher than 70 °C) have good optoelectronic properties suitable for utilization as a buffer layer in thin film solar cells.