Chemical bath deposition

About: Chemical bath deposition is a research topic. Over the lifetime, 5676 publications have been published within this topic receiving 111632 citations.

Patterned Copper Sulfide Thin Films: a Method for Studying Leaching Behaviour

Abstract: An experimental study on copper leaching from Cu185S thin films is presented, wherein copper extraction is quantitatively evaluated by changes in film thickness measured by white light interferometric profilometry Changes in the film morphology and elemental composition, as assessed by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, are used to confirm that the loss in film thickness is due to changes in the copper content and that the resultant film species is consistent with the mechanism of copper dissolution The Cu185S thin films were synthesized by chemical bath deposition The leaching behaviour of copper from the films was investigated in acidic ferric sulfate media at pHs 1, 2, and 3, and pH 1 at redox potentials of ~350–650 mV versus Ag/AgCl in 3 M KCl The changes in the film thickness and copper sulfur ratio were shown to reflect copper dissolution behaviour from chalcocite Leaching of the Cu185S films demonstrated a greater decrease in film thickness as pH decreased In addition comparison of the order of reaction as a function of proton concentration in non-oxidative dissolution of Cu185S (006) and as a function of iron(iii) concentration in ferric oxidation of Cu185S (040) shows that the proton dissolution reaction is negligible Leaching of the Cu185S films at redox potentials of up to ~4764 mV versus Ag/AgCl in 3 M KCl produced covellite and demonstrated greater decreases in film thickness with increases in the redox potential Leaching of the films above ~4764 mV resulted in the formation of spionkopite and demonstrated a much lesser decrease in film thickness These results are consistent with Eh-pH diagrams for the Cu–S–H2O system

Synthesis of Zinc Sulfide Nanocrystals by Chemical Bath Deposition Methods

Abstract: Chemical bath deposition method was used to create zinc sulfide (ZnS) nanoparticles. The CBD contained fixed components such as ZnCl2, NH4NO3, and CS (NH2)2 and KOH. Samples were heated at 90°C in a bath with magnetic agitation. Homogeneity, high transparency, adhesion, and crystalline ZnS films were achieved using KOH (1.4 M). For structural and optical investigation, the produced nanoparticles are examined using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) Spectroscopy, and ultraviolet-visible (UV-Vis) Absorption Spectroscopy. In XRD, the cubic crystal structure can be seen at 350nm, the UV-Vis spectrum reveals a blue peak. The absorbance and type of bonds present in samples are determined by FTIR spectra.

Extent of dependence of crystalline, morphological, optical and electrical properties on deposition time of sprayed SnS thin films

Abstract: In the present experimental work, Tin Sulphide (SnS) thin films with various thicknesses have been grown on nonconducting substrate by using chemical spray pyrolysis technique in order to study the extent of dependence of crystallite size, morphological and optical properties of SnS films on their deposition times. The obtained films were characterized using x‐ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), UV–visible and Hall Effect measurements. From 15 min to 60 min with an increase of 15 min each time one of all films was deposited, the XRD analysis indicated that all four sprayed SnS films are mainly composed with orthorhombic SnS phase, having a growing dominant peak intensity (120), with increasing deposition time. In addition, the XRD revealed the presence of the Sn2S3 secondary phase in SnS film sprayed at the longest time (60 min). It was found that the measurements of crystallite size and microstrain are varied in the inverse manner throughout the deposition period. The SEM and AFM analysis revealed that the morphology of sprayed films have good surface coverage without pinholes or cracks. AFM analysis confirmed that the root‐mean‐square (RMS) roughness behavior of the sprayed films increases from 14.6 to 56.7 nm with increasing deposition time. Optical studies showed that the transmittance decreases with the deposition time increase, and the minimum value of Urbach energy was 360 meV for the film deposited at 45 min, showing an improvement of the SnS film crystallinity. In addition, the optical band gap values significantly increased from 0.69 to 2.10 eV by increasing the deposition time from 15 min to 60 min. The Hall Effect study showed that SnS thin films have p‐type conductivity. The lowest resistivity and higher carrier concentration were found to be 0.134 Ω cm and 8.15 × 1019 (ion/cm−3), respectively. These obtained results revealed that the deposition time interestingly affect the properties of sprayed SnS films, which would qualifying them to meet the requirements to be serve in different applications.

Chemical phases in the solution-grown Zn(O,S) buffer of post-annealed Cu(In,Ga)Se2 solar cells investigated by transmission electron microscopy and electroreflectance

Abstract: Thin-film solar cells with Cu(In,Ga)Se2 (CIGS) absorber layers have been intensively studied due to their high power conversion efficiencies. CIGS solar cells with Zn(O,S) buffer layers achieved record efficiencies due to their reduced parasitic absorption compared with the more commonly used CdS buffer. Accordingly, we have studied solution-grown Zn(O,S) buffer layers on polycrystalline CIGS absorber layers by complementary techniques. A bandgap energy Eg of 2.9 eV is detected by means of angle-resolved electroreflectance spectroscopy corresponding to Zn(O,S), whereas an additional Eg of 2.3 eV clearly appeared for a post-annealed CIGS solar cell (250 °C in air) compared with the as-grown state. To identify the chemical phase that contributes to the Eg of 2.3 eV, the microstructure and microchemistry of the Zn(O,S) buffer layers in the as-grown state and after annealing were analyzed by different transmission electron microscopic techniques on the submicrometer scale and energy-dispersive x-ray spectroscopy. We demonstrate that the combination of these methods facilitates a comprehensive analysis of the complex phase constitution of nanoscaled buffer layers. The results show that after annealing, the Cu concentration in Zn(O,S) is increased. This observation indicates the existence of an additional Cu-containing phase with Eg close to 2.3 eV, such as Cu2Se (2.23 eV) or CuS (2.36 eV), which could be one possible origin of the low power conversion efficiency and low fill factor of the solar cell under investigation.

Formation and characterization of ZnS and CdZnS films using open-air chemical vapor deposition for buffer layers of compound semiconductor solar cells

Abstract: ZnS and CdZnS (a mixed crystal phase of ZnS and CdS) were formed using the open-air CVD method. Cadmium diethyldithiocarbamate (C10H20CdN2S4) and zinc diethyldithiocarbamate (C10H20ZnN2S4) were used as the source materials for CdS and ZnS, respectively. By changing the ratio of source materials, it was found that the bandgap and the lattice constant of the CdZnS film were continuously changing without a miscibility gap. Furthermore, the bandgap of the obtained ZnS films was less than the reported bandgap of ZnS (3.68 eV) due to incorporation of oxygen. X-ray diffraction analysis revealed that the increase of Zn in CdZnS film generated a crystalline disorder. When the substrate temperature was changed from 421 °C to 464 °C, the deposition rate increased fourfold for the CdS and ZnS films. The impact of substrate temperature on the bandgap and lattice constant was found to be less pronounced.