Showing papers on "Chemical bath deposition published in 2003"
TL;DR: In this paper, the XRD patterns show that the films are of hexagonal phase with preferred (0.0.2) orientation and the grain size increases with the thickness of the film.
262 citations
TL;DR: In this article, the optical bandgap and the type of transition were determined by the transmittance spectrum of thin films of SnS by chemical bath deposition and thermally treated in argon atmosphere at different temperatures.
Abstract: Thin films of SnS have been prepared by chemical bath deposition and thermally treated in argon atmosphere at different temperatures. As-prepared films were polycrystalline of an orthorhombic structure, but at the thermal treatment of 300 °C their preferential orientation increased. The optical bandgap and the type of transition are determined by the transmittance spectrum. The value of the optical bandgap is determined for the direct transitions of 1.38 eV which is not changed by the thermal treatment. The optical bandgap for the indirect transitions increased with the time of thermal treatment, and also the energy of phonon is estimated. From the red edge of the photoconductivity spectrum, a bandgap of Eg(ph) = 1.24 eV was also determined. An impurity level with an activation energy of 0.39 eV and a thermal bandgap of Eg(T) = 1.19 eV are determined by the temperature dependence of the dark resistance of the films.
149 citations
TL;DR: In this article, chemical bath deposition of zinc sulfide thin films using mixed aqueous solutions of zinc acetate, thiourea and tri-sodium citrate was used as the complexing agent.
Abstract: Crystalline zinc sulfide (ZnS) thin films were prepared by chemical bath deposition (CBD) using the mixed aqueous solutions of zinc acetate, thiourea and tri-sodium citrate, where tri-sodium citrate was used as the complexing agent. The thin films were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and optical absorption. The as-deposited thin films were surface homogeneous with pure wurtzite structure and the optical band gap of the film was estimated to be 3.53 eV.
145 citations
TL;DR: In this paper, the best annealing temperature for CBD grown CdS films was found to be 300°C from the optical properties, and the crystallite sizes were found to increase with wavelength and crystallite size.
133 citations
TL;DR: In this article, it was shown that even after air annealing half an hour at 623 K, the CdS films are poorly crystallized, the surface of these amorphous films is quite inhomogeneous in such a way that XPS profiles are difficult to interpret.
120 citations
TL;DR: In this article, a simple low temperature method was developed to grow cubic Cu2−xSe (x=0.2) semiconductor, semitransparent thin films, based on the reaction of CuSO4, triethanolamine, sodium selenosulphate (Na2SeSO3) in aqueous alkaline medium at 5°C.
119 citations
TL;DR: In this article, transient absorption (TA) results on the dynamics of electron relaxation and electron transfer in cadmium sulfide quantum dots (QDs) grown by chemical bath deposition techniques on nanocrystalline oxide substrates are presented.
Abstract: We present experimental transient absorption (TA) results on the dynamics of electron relaxation and electron transfer in cadmium sulfide quantum dots (QDs) grown by chemical bath deposition techniques on nanocrystalline oxide substrates. The quantum dots are prepared in situ in nanocrystalline titanium dioxide (TiO2) and zirconium oxide (ZrO2) films. The conduction band offset between the CdS QDs and TiO2 allows for efficient electron injection from the photoexcited QDs into the conduction band of TiO2. An unprecedented peak is seen in the transient absorption spectrum, which may be used to track the spectral response of the QD/TiO2 composites. Dynamic measurements in the visible and mid-IR are used to evaluate the time scale of the electron injection process. The TA dynamics for these systems are found to be multiexponential. A comparison of the TA dynamics for CdS/TiO2 and CdS/ZrO2 composites in the visible and mid-IR region indicates that electron transfer occurs on the time scale of ∼10−50 ps.
118 citations
TL;DR: In this paper, the Bruggeman's effective medium approximation and the Lorentz oscillator expression were used to analyze the ellipsometry measurements, and the complex dielectric function, thickness, roughness and void fraction of the films were examined as a function of temperature deposition.
114 citations
TL;DR: In this paper, the best annealing temperature for CBD grown CdS films was found to be 350 °C from optical properties, and the crystallite sizes were found to increase and the x-ray diffraction patterns were seen to sharpen.
Abstract: CdS films were prepared by chemical bath deposition (CBD) at 60 °C without stirring. The crystallographic structure of the films and the size of the crystallites in the films were studied by x-ray diffraction. The energy gap of the films was found to decrease by annealing. The best annealing temperature for CBD grown CdS films was found to be 350 °C from optical properties. The crystallite sizes were found to increase and the x-ray diffraction patterns were seen to sharpen by annealing. The optical properties of the films were seen to be dependent on the film thicknesses. The band edge sharpness of optical absorption was seen to oscillate by thermal annealing. Self-oxidation and sulfur evaporation were found to be responsible for this oscillating behaviour. Annealing over 400 °C was seen to degrade the optical properties of the film.
104 citations
TL;DR: In this article, a procedure to deposit ZnO thin films by CBD in an efficient way, since it offers the possibility to minimize both the undesirable homogeneous reaction in the bulk solution and the material deposition on the CBD reactor walls.
83 citations
TL;DR: In this paper, the effects of the boron doping of CdS films on the characteristics of thin-film solar cells using boric acid (H3BO3) as a dopant source were investigated.
TL;DR: The successive ionic layer adsorption and reaction (SILAR) method has been used for the first time to deposit nanocrystalline CdSe thin film onto glass substrates.
TL;DR: In this paper, chemical bath deposition (CBD) and close-spaced sublimation (CSS) techniques were applied to Cadmium Sulfide (CdS) thin films for photovoltaic applications.
TL;DR: In this paper, a more robust and reproducible baseline process for 30cm × 30 cm-sized CIGS-based thin-film circuits with a Zn(O,S,OH) x buffer layer is reported, which also leads to an achievement of 12.93% efficiency on an aperture area of 864cm 2.
TL;DR: In this article, a polycrystalline cadmium sulfide (CdS) thin film was deposited on glass substrates by chemical bath deposition and close-spaced sublimation (CSS) techniques.
TL;DR: In this paper, a comparative study of photoluminescence and its relation to the structural properties of cadmium sulphide (CdS) thin films grown by chemical bath deposition (CBD), close spaced vapour transport, laser ablation (LA), and sputtering is presented.
Abstract: In this paper, we present a comparative study of photoluminescence and its relation to the structural properties of cadmium sulphide (CdS) thin films grown by chemical bath deposition (CBD), close spaced vapour transport, laser ablation (LA) and sputtering. Taking into account that the physical properties of CdS thin films depend upon the growth technique and the optimization of the deposition conditions for each technique, we show that the best crystal perfection occurs for LA-CdS films since the main photoluminescence peak at low temperature is due to bound excitons (2.53 eV). As expected, the films with the worst crystalline quality are those grown by CBD, ascertained by the photoluminescence band around 1.72 eV due to sulfur vacancies ('red band') without the corresponding exciton band. The photoluminescence results are correlated to x-ray diffraction measurements that confirm the above results.
TL;DR: In this article, the same rate equation was successfully applied to the film growth based on the assumption that the rate of film growth is proportional to that of the precipitation, i.e., Ft = mPt, where Ft is the film thickness at time t and m is a proportionality factor.
Abstract: Chemical bath deposition of ZnS thin films (CBD) in zinc acetate-thioacetamide (TAA) aqueous solutions has been studied in the temperature range between 50 and 90 °C. The rate of film growth is compared to that of homogeneous precipitation of ZnS. The film growth was found to proceed by accumulation of ZnS nanocrystallites (4 nm) formed in the solution according to a cluster-by-cluster mechanism. The rate of the precipitation reaction in the present system has been phenomenologically well described by the rate equation, dPt/dt = k[Zn(II)]n[TAA]n, where Pt is the concentration of ZnS precipitate at time t, k is the temperature-activated reaction rate constant, and n is the apparent reaction order, which was determined as 0.64. The same rate equation was successfully applied to the film growth based on the assumption that the rate of the film growth is proportional to that of the precipitation, i.e., Ft = mPt, where Ft is the film thickness at time t and m is a proportionality factor. This result shows that...
TL;DR: In this article, the electrical properties of chemical bath deposited cadmium sulphide (CdS) layers were investigated using X-ray diffraction, atomic force microscopy, optical absorption, photoelectrochemical cell, DC electrical conductivity measurements, currentvoltage and capacitance-voltage measurements using Gold/CcdS Schottky contacts.
TL;DR: In this paper, the waveguide Raman spectrum of the ZnO films was analyzed using X-ray diffraction and M-line spectroscopy, showing that the waveguiding properties and optical losses of 3.0±0.5 dB cm −1 at λ = 632.8 µm were measured.
TL;DR: In this paper, an ammonia-free chemical bath method was proposed to deposit highly oriented CdS films on glass substrates, based on substitution of ammonia by sodium citrate as the complexing agent.
TL;DR: In this article, a novel and an eco-friendly selenisation process was proposed, which involved annealing the stacked layer, Se/In/Cu in which Cu and In were deposited using vacuum evaporation technique.
TL;DR: In this paper, the optical absorption measurements reveal that the band gaps of as-deposited amorphous and γ-MnS films are 3.23 and 3.16 eV, respectively, which agree with the previously reported values.
TL;DR: In this article, the structure and morphology of the obtained γ-MnS film were characterized, and the results showed that the film was composed of asymmetric hexagonal crystals with a size of 500-1000 nm.
Abstract: Well-crystallized γ -MnS films in a pure phase have been deposited on commercial glass substrates by chemical bath deposition. The structure and morphology of the obtained γ -MnS film were characterized, and the results showed that the film was composed of asymmetric hexagonal crystals with a size of 500–1000 nm. The photoluminescence of the γ -MnS film has been studied from 295 K down to 30 K and exhibited two emission bands centered at 1.8 and 1.66 eV, respectively. The temperature dependence of photoluminescence was also observed and interpreted using the spin-wave-assist photoluminescence model.
TL;DR: In this article, the effect of Tl doping on thin film properties of chemically deposited CdSe was investigated by using X-ray diffraction (XRD), scanning electron microscope (SEM), optical absorption, electrical conductivity and thermoelectric techniques.
TL;DR: The incorporation of polyacid in PANI, demonstrated by atomic force microscopy, ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopic studies, causes changes in the electronic structure of PANI and gives a different microstructure when compared to the unmodified PANI film as discussed by the authors.
TL;DR: The optical band gap of Cu4SnS4 has been found to be approximately 1 eV, involving direct forbidden transitions as mentioned in this paper, and the films are photosensitive, and the electrical conductivity in the dark is about 1 Ω−1 cm−1.
Abstract: Copper tin sulfide (Cu4SnS4) thin films have been prepared by heating a layer of CuS thin film deposited over an SnS thin film, both obtained by chemical bath deposition. Upon heating in a nitrogen atmosphere at 300–340 °C, the CuS layer converts to Cu8S5, which reacts with the underlying SnS thin film at about 400 °C to form Cu4SnS4. The optical band gap of Cu4SnS4 has been found to be approximately 1 eV, involving direct forbidden transitions. The films are photosensitive, and the electrical conductivity in the dark is about 1 Ω−1 cm−1.
TL;DR: The optical band gap of Pb1−xFexS solution-grown nanoparticle films was varied from 2.65 to 2.22 eV with an increase in iron concentration 0.25 ≤ x ≤ 0.75 as discussed by the authors.
Abstract: The optical band gap (Eg) of Pb1−xFexS solution-grown nanoparticle films was varied from 2.65 to 2.22 eV with an increase in iron concentration 0.25 ≤ x ≤ 0.75 in films grown at fixed pH and temperature by the chemical bath deposition method. The presence of excitonic structure in the ternary Pb1−xFexS for x ≥ 0.50 suggests increasing binding energy with increase in iron concentration in the films. A shift of excitonic peak towards higher energy with an increase in iron concentration is also observed.
TL;DR: In this article, the preparation of Ce doped BiVO 4 coatings on glass, by the thermal treatment of aqueous solutions containing a bismuth (III) ethylenediaminetetra-acetate chelate, vanadium (V) and cerium(III) species, is described.
TL;DR: In this paper, a modified chemical method using copper(II) sulphate; pentahydrate [CuSO4·5H2O] and sodium tellurite [Na2TeO3] as cationic and anionic sources, respectively.
TL;DR: In this paper, the authors investigated the influence of the ammonia and the thiourea (H 2 NCSNH 2 ) concentration, both being constituents of the chemical bath deposition (CBD) solution, at a deposition temperature of 80 °C on the microstructural and optical properties of CdS layers and on ZnO/CdS/CuGaSe 2 /Mo device parameters.