Fig 1 - uploaded by Alejandro Apolinar
Content may be subject to copyright.
X-Ray diffraction patterns of the CdS thin films for ten and twenty reaction times using acetylacetone as complexing agent. The gray line corresponds to 10 minutes of reaction and the dots for 20 minutes of reaction.
Source publication
The CdS thin films using Acetylacetone as complexing agent were prepared using the chemical bath deposition method, with bath temperature of 70°C with differences times of reaction. The thin films were characterized by X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM), optical absorption spectroscopy and Atomic Force Microscopy (AFM). The...
Similar publications
Nanocrystalline CdS thin films were successfully prepared using simple chemical bath deposition technique. Cadmium sulphate, thiourea and deionised water were used as starting precursor solution. The prepared thin films were characterized using X-ray diffractogram (XRD), Scanning electron microscope (SEM), elemental composition using energy dispers...
The thin films of cadmium oxide (CdO) were deposited using the SILAR (Successive ionic layer absorption and reaction) method at various deposition cycles. CdO thin films were made on glass substrates at a temperature of 95°C, using a cadmium acetate source material and an ammonium hydroxide solution. One of the main criteria that impact the quality...
TiO2 nanotube arrays (TNTAs) were decorated with NiO nanoparticles via a sequential chemical bath deposition (CBD) approach to yield NiO@TNTA photoanodes. In sharp contrast to pure TNTAs, NiO@TNTAs displayed increased absorption and decreased photoluminescence. Interestingly, NiO@TNTA photoanodes exhibited a higher photoelectrochemical activity for...
In this work where obtained bismuth sulfide thin films, by a simplified formulation, the method used for the synthesis of bismuth sulfide thin films, is denominated chemical bath deposition. It was determined the optical absorption characterization showed a direct bandgap between 1.3eV and 1.6eV. Scanning electron microscopy images are also reporte...
Citations
... The properties of CdS thin films can be tuned by the use of different complexing agents such as ammonia, ethylenediaminetetraacetic acid, triethanolamine, nitrilotriacetic acid, amino acids, acetylacetone, and triethanolamine. [17][18][19][20][21][22][23] The other influencing factor for CdS thin-film growth by the CBD method is the reaction temperature. 24 Although exposure to ultraviolet (UV) light during the CBD reaction also plays a very important role in the formation and design of the nanostructure and nanomorphology of the CdS thin film, very few research works on this have been reported. ...
The fabrication of a cadmium sulfide (CdS) thin film has been carried out by the chemical bath deposition method under two different conditions, namely, without UV light (nonexposed) and with UV light (exposed). The thin films were found to be uniform, smooth, and homogenous under both growth conditions. Structural and microstructural studies were carried out to understand the mechanism of thin-film growth. Under both conditions, the CdS thin film was found to be face-centered cubic structured. The UV light-exposed CdS thin film acquired acicular or flower-like over structures embedded in the continuous thin film of CdS. The optical band gap increased for the UV light-exposed CdS thin film. In addition, the dark and light currents also increased around 6 times for the UV light-exposed thin film compared to the nonexposed UV light thin films. The highest photosensitivity for the nonexposed and exposed UV light CdS thin film device was ~ 200% and 230%, respectively. A decrease in the photocurrent was detected and probed as a result of traps and the recombination of electrons and holes. Our findings suggest that photoexcitation during chemical reactions could be used as an effective tool to modulate the growth process and, in turn, to tune the optoelectrical properties.
... Numerous investigations have been developed to obtain CdS thin films by CBD. Several complexing agents in the bath solution have been used to study the properties of the CdS films such as EDTA [33], nitrilotriacetic acid [34], TEA [35], acetylacetone [36], aminoacids [37], triethanolamine [38] and ammonia [27,35,39,40] being this last the most used. However, as far as we know, only three works report the study of the properties of the films varying the ammonium hydroxide concentration as complexing agent. ...
CdS thin films were deposited on commercial glass substrates by CBD technique at constant temperature and deposition time of 90 °C and 50 min, respectively. The reaction was performed by mixing cadmium acetate, ammonium acetate, ammonium hydroxide, thiourea, and deionized water as an aqueous medium. The S/Cd ratio in the solution was kept constant at 4.46 to make sure that the films were as stoichiometric as possible. Optical, electrical, structural properties and the presence of organic compounds in the films were studied modifying the concentration of ammonium hydroxide (complexing agent) in the bath solution. X-ray diffraction patterns show that all films have the cubic phase with a preferential orientation in the plane (1 1 1). An increase of the film's resistivity from 10 ² to 10 ⁷ Ω-cm is observed by increasing the ammonium hydroxide concentration in the solution in the narrow interval of 0.18–0.36 M. Transmittance values up to 70% are obtained at the lowest concentrations of this reagent, obtaining from these spectra the highest value of the direct bandgap, 2.37 eV. Results about the presence of organic compounds and their influence on the photoluminescence properties are shown, which have not been reported to date. The main organic compound identified by FTIR is cyanamide, whose concentration is higher at the lowest ammonium hydroxide concentrations. Photoluminescence spectra of the films show green, red and orange bands, located at 2.27 eV, 1.78 eV, and 2.02 eV, respectively. An additional band was observed with low intensity at 2.99 eV associated with the presence of nanoparticles in some films. The films with the lower presence of defects, higher uniformity and best optical, electrical and structural properties for their use as window material in solar cells are those deposited from a bath solution with a 0.24 M concentration of the complexing agent.
... Zinc sulfide (ZnS) is a wide direct band gap, high optical absorption coefficient, reasonable work function. It has attracted considerable attention due to its excellent electrical and optical properties with its distinct properties has become the potential candidate for many applications [5][6][7][8]. ...
A solar cell with glass/ITO/ZnS/Cu2ZnSnS4/CdTe/In structure has been fabricated using all-electrodeposited ZnS, Cu2ZnSnS4 and CdTe thin films. The three semiconductor layers were electrodeposited using a two-electrode system for process simplification. The incorporation of a wide bandgap amorphous ZnS as a buffer/window layer to form ITO/ZnS/Cu2ZnSnS4/CdTe/In solar cell resulted in the formation of this 3-layer device structure. This has yielded corresponding improvement in all the solar cell parameters resulting in a conversion efficiency >12% under AM1.5 illumination conditions at room temperature. These results demonstrate the advantages of the multi-layer device architecture over the conventional 2-layer structure.
... Zinc sulfide (ZnS) is a wide direct band gap, high optical absorption coefficient, reasonable work function. It has attracted considerable attention due to its excellent electrical and optical properties with its distinct properties has become the potential candidate for many applications [5][6][7][8]. ...
... Due to wide band gap (E g = 2.4 eV) it has been used as the window material together with several semiconductors such as CdTe [1], Cu 2 S [2], InP [3] and CuInSe 2 [4] etc. and obtained maximum conversion efficiency~14-16% [5]. In addition CdS has been successfully employed in chemical sensor [6], surface acoustic wave devices [7] and photo-anode films of solar cells [8], thin film transistors (TFT), photocatalysis and biological sensors [9], optical coding, optical data storage and sensing [10], non-linear integrated optical devices [11]. ...
Thin films of cadmium sulfide (CdS) have been deposited at room temperature by using RF-magnetron sputtering at various deposition times. Films were systematically investigated using variety of techniques such as low angle XRD, UV–Visible spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDAX), atomic force microscopy (AFM), transmission electron microscopy (TEM), four probe Van der Pauw method etc. Low angle XRD and TEM analysis revealed that films are polycrystalline having constant average crystalline size. EDAX revealed the formation of nearly stoichiometric CdS films. Surface morphology of CdS films examined using SEM shows the formation of smooth, continuous and dense films without defects such as cracks, pinholes, and protrusion. RMS roughness estimated using AFM increases with increase in deposition time. The optical studies showed decrease in band gap with increase in deposition time. The photodetector fabricated using RF sputtered CdS film show an excellent photo-response. Estimated value of growth exponent β was found ~0.53 which suggests uncorrelated growth of CdS films by RF sputtering. The uncorrelated growth of CdS was further confirmed by Monte-Carlo simulation.
... Due to wide band gap (E g = 2.4 eV) it has been used as the window material together with several semiconductors such as CdTe [1], Cu 2 S [2], InP [3] and CuInSe 2 [4] etc. and obtained maximum conversion efficiency~14-16% [5]. In addition CdS has been successfully employed in chemical sensor [6], surface acoustic wave devices [7] and photo-anode films of solar cells [8], thin film transistors (TFT), photocatalysis and biological sensors [9], optical coding, optical data storage and sensing [10], non-linear integrated optical devices [11]. ...
Thin films of cadmium sulfide (CdS) have been deposited at room temperature by using RF-magnetron sputtering at various deposition times. Films were systematically investigated using variety of techniques such as low angle XRD, UV–Visible spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDAX), atomic force microscopy (AFM), transmission electron microscopy (TEM), four probe Van der Pauw method etc. Low angle XRD and TEM analysis revealed that films are polycrystalline having constant average crystalline size. EDAX revealed the formation of nearly stoichiometric CdS films. Surface morphology of CdS films examined using SEM shows the formation of smooth, continuous and dense films without defects such as cracks, pinholes, and protrusion. RMS roughness estimated using AFM increases with increase in deposition time. The optical studies showed decrease in band gap with increase in deposition time. The photodetector fabricated using RF sputtered CdS film show an excellent photo-response. Estimated value of growth exponent β was found ~0.53 which suggests uncorrelated growth of CdS films by RF sputtering. The uncorrelated growth of CdS was further confirmed by Monte-Carlo simulation.
... In recent years there has been growing interest in CdS thin films compare to its bulk counterpart due to excellent properties such as tunable band gap (2.1-2.45 eV) [2], high carrier concentration (10 16 -10 18 cm -3 ) [3] and mobility (0.1-10 cm 2 V -1 s -1 ) [4], high absorption coefficient (> 10 4 cm -1 ), high electrochemical stability [5] etc. The material has been successfully employed in chemical sensor [6], surface acoustic wave devices [7] and photo-anode films of solar cells [8,9 ], thin film transistors (TFT), photocatalysis and biological sensors [10], optical coding, optical data storage and sensing [11,12], non-linear integrated optical devices [13,14]. As per as solar cells are concerned, CdS has been used as a window material together with several semiconductors such as CIGS, CZTS, CdTe, Cu2S etc. based solar cells [15][16][17]. ...
Synthesis of CdS thin films were carried out onto glass substrates by chemical bath deposition (CBD) method using CdCl2asCd 2+ and thiourea as S 2-ion source with ammonia as a complexing agent. Influence of bath temperature on structural, morphology and optical properties has been systematically and carefully investigated. XRD analysis revealed that the synthesized CdS films are nanocrystalline having hexagonal structure with (002) preferential orientation. Estimated crystallite size was found in the range 16-32 nm. The UV-Visible spectroscopy analysis showed that the films have high transmission (> 70 %) in visible and NIR region of solar spectrum. Optical band gap was found > 2.3 eV over the entire range of bath temperature studied. The Raman spectra for the CdS films deposited at various bath temperatures shows a continuous shift of 1 LO phonon peak towards higher frequency which suggest the improvement of structural order with increase in bath temperature. The increase in the intensity ratio, 2LO/1LO with bath temperature indicates enhancement of crystallinity of CdS films with increase in bath temperature. The SEM analysis showed that CdS films deposited at various bath temperatures are smooth, homogeneous, and nearly uniform with randomly oriented spherical nanocrystallites.
... II-VI semiconductors have transparency properties in the visible range, acoustic characteristics, high electrochemical stability and excellent electronic properties. It has been widely used in chemical sensor [1], surface acoustic wave device [2] and photoanode films of solar cell [3,4]. Different techniques are available to prepare CdS nanostructures including sputtering [5,6], chemical vapor deposition (CVD) [7] and spray pyrolysis [8]. ...
... Annealing temperature * (°C/h) CdS nanostructures deposited on glass and quartz substrates are given in Table 2. The obtained values give a good agreement with experimental and theoretical results [1,12,[21][22][23]. The refractive index n is an important physical parameter related to microscopic atomic interactions. ...
Sol-gel spin coating technique is used to prepare nanostructured CdS deposited on glass and quartz substrates with Cd:S 1.2:0.1 mol/L, 1000 rpm spin coating speed at 400 degrees C and 800 degrees C annealing temperatures, respectively. The effect of hydrothermal treatment on physical properties of crystalline size and morphology is reported. Structural, topographical and optical properties are investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), UV-visible spectrophotometer (UV) and photoluminescence (PL). The optical properties are investigated experimentally and theoretically to verify the suitable model for electro-optical systems. Our results are in agreement with experimental and theoretical data.
... In chemical methods, as sol-gel, the use of additives to improve transparency and reduce electric resistivity has become common. Acetylacetone, has been successfully used to enhance the properties of TiO 2 [7] and CdS [8,9] films because it modifies the hydrolysis process and form complexes with metallic ions, leading to small particle size and selective crystalline phase formation [10]. Only two works have reported the use of acetylacetone as hydrolysis modifier for the preparation of ATO films and no systematic study on its effects on ATO films properties have been yet reported [6,11]. ...
ATO thin films have been successfully prepared by the spin coating method using an ethanol solution of SnCl4·5H2O and SbCl3 using acetylacetone as hydrolysis modifier. ATO films from 1 to 6 layers were prepared at 300 °C as densification temperature and within an annealing temperature ranging from 450 °C to 750 °C. Films exhibited the cassiterite crystalline phase and morphology consisted in nanoparticles of about 10 nm in diameter. Acetylacetone content as well the addition of water affected the particle size and morphology, decreasing particle size and the appearance of voids. Films prepared at an acetylacetone ratio of 4 with no addition of water exhibited an optical transparency above 90% from 380 to 800 nm while resistivity was 7.99 x10-3 Ω·cm. The effect of the hydrolysis modifier on the electric properties, morphology, optical transparency and microstructure has been studied
... Among the many different methods available to deposit films of semiconductors, chemical bath deposition (CBD) must rank as the simplest conceptually [1][2][3]. CBD refers to depositions from solution (usually aqueous) where the required deposit is both chemically generated and deposited in the same bath [4][5][6][7]. Thus, deposition from a supersaturated solution or spin coating from a colloidal sol are not included under the aegis of CBD: in both cases, the layer material must be pre-prepared. ...
In this work, the results of the investigation of the precularity near the solar spectrum region, of Zn 1−x Cd x S nanoparticles, nanofilms, nanoscale p-n and heterojunction prepared on glass-ceramic and alumminium sub-strates by precipitation from aqueous solutions are presented. We investigated the preparation of ZnCdS nanoparticles in a micro-emulsion system stabilized with nonionic surface active materials, as well as the impact of drop volume and supersaturation the size of the formed ZnCdS particles. The temperature dependence of dark and light conductivity, spectrum and optical quenching of primary and impurity photo-conductivity were investigated. Direct current-voltage characteristic structure of Al/p-CdS/n-CdS is almost identical to the current-voltage characteristics of p-n junctions. Volt-farad characteristics of the samples established the presence of conduction due to the presence of reverse bias p-n junctions. In the following order, CdTe/CdS/Zn 1−x Cd x S structure have 75% or slightly higher quantum efficiency in the 400–850 nm wavelength region.
