Properties Of CdS Thin Films Research Articles

Effect of molarity on the optical and structural properties of CdS thin films deposited by spray pyrolysis on flexible plastic substrates

Effect of molarity on the optical and structural properties of CdS thin films deposited by spray pyrolysis on flexible plastic substrates

Effect of coating temperature on the properties of CdS thin films coated by nebulizer spray pyrolysis method for photodetection applications

Nanostructured CdS-based photodetectors have been focused on recent years because of their high photosensitivity and quick response time. This work reports the photodetector characteristics of CdS thin films prepared using a nebulizer-assisted spray pyrolysis technique by varying substrate temperatures. The X-ray diffraction (XRD) pattern of CdS films exhibits hexagonal structure with orientation along the (002) plane and CdS films deposited at 450 °C exhibits a higher crystallite size of 53 nm. Morphological analysis shows that the small grains become large spherical flakes at higher substrate temperatures. The optical studies showed that around the visible region, the films exhibit solid optical absorbance, and when substrate temperatures rise to 450 °C, the energy bandgap value decreases to 2.29 eV. The photoluminescence (PL) spectra exhibit two emission peaks: a broad peak at 525 nm and a sharp dominant peak at 680 nm. The CdS thin film deposited at 450 °C produced the highest photoresponsivity (R) of 37.1 × 10-2 A/W, detectivity (D*) of 268 x108 Jones, external quantum efficiency (EQE) of 120 %, and response/recovery times of 0.92/0.28 s under 532 nm illumination. The study suggests that CdS thin films are suitable for visible photodetector applications due to their simple and cost-effective production process.

Comprehensive characterization of structural, optical and electrical properties of CdS thin films annealed in air and vacuum

Comprehensive characterization of structural, optical and electrical properties of CdS thin films annealed in air and vacuum

Enhancement of Photo-Electrical Properties of CdS Thin Films: Effect of N2 Purging and N2 Annealing

The impact of N2 purging in the CdS deposition bath and subsequent N2 annealing is examined and contrasted with conventional CdS films, which were deposited without purging and annealed in ambient air. All films were fabricated using the chemical bath deposition method at a temperature of 80 °C on fluorine-doped tin oxide glass slides (FTO). N2 purged films were deposited by introducing nitrogen gas into the deposition bath throughout the CdS deposition process. Subsequently, both N2 purged and un-purged films underwent annealing at temperatures ranging from 100 to 500 °C for one hour, either in a nitrogen or ambient air environment. Photoelectrochemical (PEC) cell studies reveal that films subjected to both N2 purging and N2 annealing exhibit a notable enhancement of 37.5% and 27% in ISC (short-circuit current) and VOC (open-circuit voltage) values, accompanied by a 5% improvement in optical transmittance compared to conventional CdS thin films. The films annealed at 300 °C demonstrate the highest ISC, VOC, and VFB values, 55 μA, 0.475 V, and −675 mV, respectively. The improved optoelectrical properties in both N2-purged and N2-annealed films are attributed to their well-packed structure, enhanced interconnectivity, and a higher sulfur to cadmium ratio of 0.76 in the films.

Utilizing Gold Nanoparticle Decoration for Enhanced UV Photodetection in CdS Thin Films Fabricated by Pulsed Laser Deposition: Exploiting Plasmon-Induced Effects.

UV sensors hold significant promise for various applications in both military and civilian domains. However, achieving exceptional detectivity, responsivity, and rapid rise/decay times remains a notable challenge. In this study, we address this challenge by investigating the photodetection properties of CdS thin films and the influence of surface-deposited gold nanoparticles (AuNPs) on their performance. CdS thin films were produced using the pulsed laser deposition (PLD) technique on glass substrates, with CdS layers at a 100, 150, and 200 nm thickness. Extensive characterization was performed to evaluate the thin films' structural, morphological, and optical properties. Photodetector devices based on CdS and AuNPs/CdS films were fabricated, and their performance parameters were evaluated under 365 nm light illumination. Our findings demonstrated that reducing CdS layer thickness enhanced performance concerning detectivity, responsivity, external quantum efficiency (EQE), and photocurrent gain. Furthermore, AuNP deposition on the surface of CdS films exhibited a substantial influence, especially on devices with thinner CdS layers. Among the configurations, AuNPs/CdS(100 nm) demonstrated the highest values in all evaluated parameters, including detectivity (1.1×1012 Jones), responsivity (13.86 A/W), EQE (47.2%), and photocurrent gain (9.2).

Towards halide treatment on CdS thin films for solar cell applications: An evolution to ion size impact on segregation and grain boundaries passivation

In this study, an impact of halide ion size on the physical properties of 200 nm thin thermally evaporated CdS films is explored. The ex-situ halide treatment is performed using 0.2 M solutions of halide compounds viz. CdCl2, CdI2, MgF2, MgCl2 and MgI2 separately and subsequently air annealing at 200 °C. A detailed grain growth mechanism in CdS films based upon nature and size of cations and anions to the treatment species is deeply discussed. The recrystallization responsible for modulation in structural, optical, topographical, photoluminescence, electrical, morphological and compositional properties of CdS films is explored via formation of different complexes. The XRD patterns reveal formation of polycrystalline CdS thin films having mixture of cubic (with space group F4̅ 3 m) and hexagonal phases with (220) cubic preferential orientation. Different crystallographic constants are calculated and discussed where the crystallite size is varied from 34 nm to 48 nm with treatment. Surface topographical study indicates that surface roughness is altered with the halide treatment and observed maximum for MgCl2 treated CdS thin films. The pristine and halide treated CdS thin films show Ohmic nature owing to linear current-voltage behavior. Optical study demonstrates that MgI2 treated films have higher transmittance and lower absorbance and energy band gap is measured out in 2.04–2.48 eV range. PL spectra of CdS films reveal a strong red emission band appeared at ∼685 nm corresponding to Sulfur vacancies (VS) and possible A centers (XS+VCd2−)−. FESEM exploration reveals grain growth with probable activation where maximum grain size is obtained for MgF2 treated films. The EDS patterns confirm deposition of CdS films and also integration of F, Cl, I and Mg in the associated treated CdS films. The investigated findings reveal that size of halide ions plays a decisive role in modification of the physical properties of CdS thin films which could be implicated as optical window to CdTe and CIGS based photovoltaic devices.

Engineering the physical properties of CdS thin films through incorporation of Fe dopant for photodetector applications

Pure CdS and 1, 2, 3, 4, and 5 wt% Fe-doped CdS thin films have been fabricated on glass substrates at a coating temperature of 450 °C by a simple and economical spray-pyrolysis technique. The prepared samples have been characterized by various analytical techniques to assess their crystalline, morphological, optical, and photo-sensing properties. X-ray diffraction (XRD) analysis has revealed the presence of the hexagonal wurtzite phase of CdS, with (002) as the predominant plane. With the incorporation of the Fe dopant into CdS, the peak of the predominant plane (002) increases, suggesting an increase in the crystallinity of the samples. The CdS:Fe4% sample showed the largest crystallite size of 49 nm. The morphologies of the prepared thin films reveal uniform clusters of very fine nanoparticles, with the incorporation of Fe ions in CdS improving the particle size and porosity, which is beneficial for light harvesting. UV/Vis studies have indicated an improvement in the optical absorption of the CdS:Fe4% sample, with a reduction in the band gap to 2.29 eV. Photoluminescence (PL) spectra feature broad emission peaks at around 460, 535, and 640 nm, the intensities of which increase with the incorporation of the Fe dopant, suggesting improved radiative recombination of excitons and defect sites, such as S vacancies and Cd vacancies. Photo-sensing studies of the fabricated devices showed the highest photocurrent (28 μA), responsivity (5.59 × 10−1 AW−1), detectivity (9.05 × 1010 Jones), and external quantum efficiency (180%), as well as the shortest response time (0.1 s) and recovery time (0.2 s), for the CdS:Fe4% photodetector, suggesting that this sample is best suited for commercial application in photodetectors.

Morphology and optical properties of CdS thin films prepared by Physical Vapor Deposition method

The optical properties of cadmium sulfide thin films obtained by thermal evaporation in vacuum were studied. The stoichiometric compositions of the binary compound previously synthesized from high-purity powders of the initial components were used. Films of different thicknesses deposited on a glass substrate were investigated using scanning electron microscopy and absorption coefficient was defined by the Swanepoel method. It was found that with increasing film thickness, surface formations decrease and at a thickness of 1 μm the film surface is continuous. It is determined that thin films of cadmium sulfide have optimal optical parameters for use as photovoltaic buffer layer. All the obtained films except the film with a thickness of 1215 nm show the usual interference pattern in the reflection spectra.

Influence of Substrate Temperature on Structural Properties of CdS Thin Films Prepared by Chemical Spray pyrolysis

الملخص:في هذا البحث تم تحضير أغشية CdS الرقيقة بطريقة شلل الرذاذ الكيميائي على طبقة زجاجية بدرجات حرارة مختلفة عن نترات الكادميوم بسمك ثابت (440 ± 10 نانومتر) ، لدراسة تأثير درجة حرارة الركيزة على خواص بنية الأغشية المحضرة.أظهرت نتائج القياسات الهيكلية من خلال مجهر المسح الإلكتروني (SEM) تجانس الأفلام المعدة ، ومن نتائج مجهر القوة الذرية (AFM) ، فإن الجسيمات النانوية هي التركيب وقيمة الجذر التربيعي لمتوسط ​​الخشونة (RMS) ) من الأغشية الرقيقة متساوية (0.699 نانومتر). ومن نمط حيود الأشعة السينية ، أظهرت النتائج أن جميع الأفلام متعددة البلورات ، وهيكل سداسي ، وحجم الحبيبات في نطاق مقياس النانو ، ودرجة حرارة الركيزة لا تؤثر على التركيب البلوري للأغشية ، وأن الفيلم المحضر له اتجاه مفضل على طول (002) (أي المحور C عمودي على الركيزة).الكلمات الرئيسية: CdS ، CSP ، الخواص التركيبية.

A review on Physical Properties of CdS Thin Film

CdS Cadmium Sulfide is the important semiconductor materials. Semiconductors are solids with conductivities ranged from 104 to 10-10 (n cm)-l. The properties of CdS are structural, Electrical and Optical. We examine a number of papers published between 1983 and 2015 that created CdS thin films in a variety of ways, including chemical bath deposition, spray pyrolysis, thermal evaporation, close spaced sublimation, and pulsed laser ablation. They found band gap energy in (eV), Refractive index (n) and Extension coefficient (k). X-ray diffraction, the researchers employed energy dispersive X-ray spectroscopy with scanning electron microscopy in this study. The crystallinity the quality of the movie improves after annealing, As a result, optical transmittance is reduced. The structure is hexagonal in general. All of the films are ideal as efficient for solar cell applications, there are a number of different window layers that may be used. Due to their high transmittance and low resistance values. These findings suggest that CBD films with a broad Low resistivity, high mobility, and a high carrier concentration are all characteristics of the band gap. Produced at pH 11 are ideal contenders for use in various optoelectronic devices.

The effect of CO32− on the structural and optical properties of CdS thin films prepared by chemical bath deposition

The effect of CO32− on the structural and optical properties of CdS thin films prepared by chemical bath deposition

Comparison of optical properties of CdS thin films synthesized by spray pyrolysis and thermal evaporation method

Comparison of optical properties of CdS thin films synthesized by spray pyrolysis and thermal evaporation method

Influence of Cd salt concentration on the photoconductivity of CdS thin films prepared by chemical bath technique

Herein, a comparative study of the photodetection properties of CdS thin films deposited via the CBD method at different cadmium chloride concentrations of Cd (0.008) M, Cd (0.02) M, and Cd (0.08) M has been reported. The increase in cadmium salt concentration dominated the cluster deposition mechanism of the chemical bath deposition (CBD) method, leading to the cubic crystal phase and the thicker CdS thin films. Also, with the increase in cadmium salt concentration, the photosensivity decreased. After all investigations, it was concluded that the value of photosensivity strongly depends on the film thickness and the quantum confinement effect, as well as the amount of sulfur vacancy of samples grown by the CBD method. The quantum confinement effect of sample Cd (0.008 M) was proved by the blue shift of the optical band gap and the grain size of this sample shown by Transmission Electron Microscope (TEM). The structural properties, surface morphology, compositional properties, film thickness and optical properties of CdS thin films were studied by X-Ray Diffractometer (XRD), Field Emission-Scanning Electron Microscopy (FE-SEM), TEM, Energy Dispersive X-ray Spectroscopy (EDXS), Cross-Section Microscopy (CSM), UV–Vis Spectroscopy, and Photoluminescence Spectroscopy (PL), respectively. Besides, the optical sensor characteristics of these samples were analyzed by the I–V curves at a bias voltage of 5V. The results showed more than 200 times the photosensivity of sample Cd (0.008 M) compared to the sample Cd (0.08 M); 265 vs.1.3.

Theoretical Analysis of Solar Cell Performance with Different Backsurface‐Filed Layers Utilizing Experimental Results of CdS Films Deposited by Pulsed Laser

Herein, three different backsurface‐filed (BSF) layers “SnS, PbS, and V2O5” are investigated on Mo/BSF/CZTS/CdS/AZO heterojunction solar cells using experimental data of CdS thin films. CdS thin films are produced by means of the pulsed laser deposition (PLD) technique with three different deposition periods. With increasing deposition time, the crystalline sizes of CdS thin films are larger and their crystal structures are developed. In addition, the optical bandgap of CdS thin films is calculated to be 2.4 eV using the absorbance data. Using the solar cell–capacitance–simulator‐1D (SCAPS‐1D) program, the experimental properties of CdS thin films to estimate the performance of p‐CZTS/n‐CdS/AZO heterojunction solar cells are introduced. The best efficiency is 9.32% when the thickness of CdS reaches 150 nm. To further improve the efficiency, different BSF layers (SnS, PbS, and V2O5) are tested in Mo/BSF/CZTS/CdS/AZO solar cells. According to the thickness of the BSF layer, the efficiency of the solar cell increases up to 13.47%, 14.7%, and 17.41% using SnS, PbS, and V2O5 as BSF layers with 0.1 μm thickness.

Structural, Optical and Photo Catalytic Properties of CdS Thin Films Synthesized by Green-CBD Method

Aim of this work is to study the synthesis of CdS thin films by eco-friendly rout and analyze the change in structural and optical properties of material due to use of biomolecules as a stabilizing agent. The CdS thin films were deposited in lemon extract and ammonia solution separately by maintaining the same physical parameters and analyzed for tailoring of structural and optical properties. Green-CBD method minimizes the use of toxic precursors and volatilization of ammonia solution. X-Ray Diffraction study indicates formation of face centered cubic crystalline phase predominantly for CdS thin films materials with change in grain size. SEM analysis revealed the formation of CdS nanospheres in ammonia while CdS nanocubes in lemon extract. The direct allowed band gap energy was observed in the order of 2.45 eV and 2.25 eV which were interesting for optical studies. UV-Vis Absorption spectra and PL spectra of thin films indicates the CdS thin film material has absorption maxima in visible (400-800 nm) region. As synthesized CdS thin films were applied for photodegradation of Rhodamine-B dye solution under sunlight. The CdS thin film material deposited by Green-CBD rout shows high efficiency for degradation of Rhodamine-B solution as compared to films deposited by CBD method.

Mechanism and principle of doping: realizing of silver incorporation in CdS thin film via doping concentration effect.

A high-quality buffer layer serves as one of the most significant issues that influences the efficiency of solar cells. Doping in semiconductors is an important strategy that can be used to control the reaction growth. In this study, the influence of Ag doping on the morphological, optical and electrical properties of CdS thin films have been obtained. Herein, we propose the mechanism of CdS film formation with and without Ag ions, and we found that changes in the reaction of preparing CdS by the chemical bath deposition (CBD) method cause a shift in the geometric composition of the CdS film. XRD showed that the position of peaks in the doped films are displaced to wider angles, indicating a drop in the crystal lattice constant. The optical analysis confirmed direct transition with an optical energy gap between 2.10 and 2.43 eV. The morphological studies show conglomerates with inhomogeneously distributed spherical grains with an increase of the Ag ratio. The electrical data revealed that the annealed Ag-doped CdS with 5% Ag has the highest carrier concentration (3.28 × 1015 cm-3) and the lowest resistivity (45.2 Ω cm). According to the results, the optimal Ag ratio was obtained at Ag 5%, which encourages the usage of CdS in this ratio as an efficient buffer layer on photovoltaic devices.

Probing the significance of RF magnetron sputtering conditions on the physical properties of CdS thin films for ultra-thin CdTe photovoltaic applications

We comprehensively explored the impact of RF magnetron sputtering conditions on the physical properties of CdS thin films for the first time. Structural, morphological, and compositional properties were altered to a great extent by the sputtering conditions. Very high average transmittances of 94%, 92.5%, 91% and 89% were achieved in CdS thin films with thicknesses of 40, 60, 80, and 100 nm, respectively. A 100-nm thick CdS thin film showed an excessively high mobility of 92 cm2/V·s with an optimum carrier concentration of 1017 cm−3 and resistivity of 103 Ω·cm. An ultra-thin CdTe film (480 nm) with a smooth and crack-free surface was achieved with RF magnetron sputtering. As proof of concept, ultra-thin CdTe solar cells were fabricated by incorporating CdS thin films with thicknesses varying from 40 to 100 nm, and the power conversion efficiency was enhanced from 1.18% to 4.13%, respectively. This work highlights the importance of investigating sputtering conditions to achieve CdS with superior physical properties and enhance ultra-thin CdTe solar cell performance.

The role of Ag layer in the optical properties of CdS thin film

CdS and CdS capped with Ag thin layer thin films were organized by chemical bath deposition technique. Cadmium chloride and thiouria were used as precursors material to deposited CdS film at 80 C. after deposition of CdS film, it dipped in Ag NPs. precursors for one hour at 50 C to coated it surface by Ag layer. In this paper, we examined the absorbance in the range between 300 and 1100 nm. The direct and indirect band gaps were calculated with the Tauc method, yielding values of 1.97 to 2.46 eV. Resulting noticeable decreasing in band gaps with the presence of Ag layer.

Influence of aluminum doping on structural, morphological, vibrational, and optical properties of CdS thin films obtained by chemical bath deposition

Thin films of CdS and Al-doped CdS have been successfully deposited on glass substrates by using a CBD technique and their properties were investigated. The structural analysis confirmed the hexagonal structure of CdS with preferential orientation along (002) planes. Crystallite sizes decreases with Al content. The AFM images of the films show changes in morphology with increase the dopant concentration. Raman scattering were composed of fundamental longitudinal optical (LO) modes and their multi-phonon process. Transmittance, reflectance, refraction index and extinction coefficient were studied to extract the optical properties variation upon Al doping. The increase of the lattice strain due to Al doping modifies the optical properties of the films. The energy band gap was found to increase from 2.3 to 2.6 eV with increase in Al content. The doping also affects the photoluminescence properties of CdS crystal structure, causing a shift towards shorter wavelengths of the peaks of Al-doped films.

Influence of pH on the physical properties of CdS thin film and its photosensor application

Influence of pH on the physical properties of CdS thin film and its photosensor application