Showing papers on "Chemical bath deposition published in 1994"
TL;DR: In this article, high efficiency CdTe/CdS thin film solar cells have been prepared on SnO2-coated borosilicate glass substrates, and conversion efficiencies of over 15% have been achieved as a result of optimization of a number of processing steps.
110 citations
TL;DR: In this article, cubic CdS thin films with low resistivity by chemical bath deposition (CBD) technique and subsequent annealings in S2 and H2+In were reported.
Abstract: In this letter we report on cubic CdS thin films with low resistivity by chemical bath deposition (CBD) technique and subsequent annealings in S2 and H2+In. Low temperature photoluminescence, x rays, and transmission spectra support the assumption that S2 annealings contribute to fill the vacancies in the as‐deposited films leading to an enlargement of the CdS cubic cell. This fact is revealed by an increase in interplanar distances, evanescence of the PL red broad band, and decrease in band‐gap energies. Cubic phase remains after H2+In annealing at higher temperatures. A resistivity as low as 11 Ω cm was obtained at an optimum annealing temperature of 350 °C.
94 citations
TL;DR: In this paper, chemical bath deposition techniques for ZnSe and CuSe thin films using N,N-dimethylselenourea as the source of selenide ion are presented.
Abstract: Chemical bath deposition techniques for ZnSe and CuSe thin films using N,N-dimethylselenourea as the source of selenide ion are presented. Films of 0.1 to 0.3 [mu]m in thickness of ZnSe and CuSe are obtained in 2 to 10 h depositions at 50 C. The ZnSe films possess optical bandgap [approximately]2.63 eV and suffer thermal degradation at temperatures >350 C. They are very resistive, with sheet resistance [approximately]10[sup 12] [Omega]/[open square] ([approximately]0.3 [mu]m film, 10 h deposition). The CuSe films have sheet resistance [approximately]10[sup 3] [Omega]/[open square] ([approximately]0.13 [mu]m, 3 h deposition) but undergo thermal degradation at temperature >200 C. Structure, composition, optical, and electrical characteristics of the films are discussed.
73 citations
TL;DR: In this paper, the authors report the preparation and characterization of large area n-type conducting CdO films for the first time by a low cost technique, viz. the chemical bath deposition.
Abstract: In the present note we report the preparation and characterization of large area n-type conducting CdO films for the first time by a low cost technique, viz. the chemical bath deposition. (orig.)
28 citations
TL;DR: In this paper, an attempt was made to modify the band gap of CdS (∼ 2.4 eV) by preparing a mixed lattice with a low-band-gap material, PbS (0.3 eV), giving a new set of materials, CdxPb1−xS.
Abstract: An attempt was made to modify the band gap of CdS (∼ 2.4 eV) by preparing a mixed lattice with a low-band-gap material, PbS (0.3 eV), giving a new set of materials, CdxPb1−xS. Band gaps as low as ∼ 1.9 eV were achieved with increasing x. The preparation of CdxPb1−xS was carried out by chemical-bath deposition. Structural characterization studies using X-ray diffraction (XRD), energy dispersion analysis by X-rays (EDAX), and optical microscopy were performed. The optical-absorption studies used to find the band gap are also described.
20 citations
05 Dec 1994
TL;DR: In this paper, a thin film is used for solar cells based on Cu(In,Ga)Se/sub 2/ and thioacetamide in order to characterize the growth kinetics and the chemical composition.
Abstract: Solar cells based on Cu(In,Ga)Se/sub 2/ were prepared replacing the 'standard buffer layer' CdS with a In/sub x/(OH,S)/sub y/ thin film. The film is deposited in a chemical bath (CBD) process using an aqueous solution containing InCl/sub 3/ and thioacetamide. X-ray photoemission spectroscopy measurements were performed in order to characterize the growth kinetics and the chemical composition. The influence of different concentrations of InCl/sub 3/ and thioacetamide in the solution on the electrical properties of the solar cells was studied by measuring the j-V characteristics and the spectral quantum efficiencies. Capacitance-voltage (C-V) measurements indicate that the high V/sub oc/ values of devices with the novel buffer layer are correlated with narrower space charge widths and higher effective carrier concentrations in the absorber materials. The achieved conversion efficiency of approximately 15% using the cadmium free In/sub x/(OH,S)/sub y/ buffer demonstrates the potential of this process as an alternative to the standard chemical bath deposition of CdS.
15 citations
TL;DR: In this paper, the properties of chemical bath deposited CdS thin films were investigated and it was found that the thickness and crystallinity of the films were affected by the pH value and temperature of the solutions.
9 citations
05 Dec 1994
TL;DR: In this paper, Cadmium sulfide films prepared by RF sputtering and close spaced sublimation (CSS) have been used for the fabrication of CdTe/CdS thin film solar cells on borosilicate glass substrates.
Abstract: Cadmium sulfide films prepared by RF sputtering and close spaced sublimation (CSS) have been used for the fabrication of CdTe/CdS thin film solar cells on borosilicate glass substrates. The CdTe layer was prepared by CSS at high processing temperatures (600/spl deg/C). CdS films prepared by the chemical bath deposition process (CBD) were deposited on tin oxide coated soda lime glass substrates. For these devices the CSS CdTe films were prepared at low substrate temperatures (<550/spl deg/C). Devices prepared at low processing temperatures (CdTe-CSS/CdS-CBD) on soda lime glass substrates exhibited efficiencies in excess of 13% as measured under AM 1.5 conditions at the National Renewable Energy Laboratory.
7 citations
05 Dec 1994
TL;DR: In this article, the optical and electrical properties of chemical bath deposited CdS films are characterized as a function of bath chemistry and annealing treatments, and changes in band gap and broadening parameter are evident and discussed in terms of quantum size effects and structural defects.
Abstract: Optical and electrical properties of chemical bath deposited CdS films are characterized as a function of the bath chemistry and annealing treatments. Changes in band gap and broadening parameter are evident and discussed in terms of quantum size effects and structural defects. The films are n-type and photosensitive with carrier concentrations around 10/sup 17/ cm/sup -3/.
6 citations
TL;DR: In this article, chemical bath deposition techniques for ZnSe and CuSe thin films using N,N-dimethylselenourea as the source of selenide ion are presented.
Abstract: Chemical bath deposition techniques for ZnSe and CuSe thin films using N,N-dimethylselenourea as the source of selenide ion are presented. Films of 0.1 to 0.3 [mu]m in thickness of ZnSe and CuSe are obtained in 2 to 10 h depositions at 50 C. The ZnSe films possess optical bandgap [approximately]2.63 eV and suffer thermal degradation at temperatures >350 C. They are very resistive, with sheet resistance [approximately]10[sup 12] [Omega]/[open square] ([approximately]0.3 [mu]m film, 10 h deposition). The CuSe films have sheet resistance [approximately]10[sup 3] [Omega]/[open square] ([approximately]0.13 [mu]m, 3 h deposition) but undergo thermal degradation at temperature >200 C. Structure, composition, optical, and electrical characteristics of the films are discussed.
6 citations
05 Dec 1994
TL;DR: In this article, the properties of the solution obtained in thin film form by screen printing and sintering technique were analyzed and the optimal annealing conditions were found where the films were single phase and homogeneous.
Abstract: Important progress has been reached in the elaboration of low cost solar cells based in CdS/CdTe heterostructures. This was accomplished by using different techniques such as chemical bath deposition, close space sublimation, electrodeposition and screen printing and sintering. In all these low cost techniques, at least a relatively high temperature step is necessary during the processing for the completion of the cell. Under these conditions, a CdSxTe1-x interfacial layer is formed which has great influence in the cell parameters and performance. In this work we present a study of the properties of this solution obtained in thin film form by screen printing and sintering technique. Optimal annealing conditions were found where the films were single phase and homogeneous. The samples were characterized by optical microscopy, talystep profiles, X-ray diffraction patterns, optical transmission and photoluminescence (PL) spectra.