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The economic spray pyrolysis process were used to prepare Zinc oxide thin films. Ahigh - quality thin film is obtained by optimizing factors that include concentration, flow rate, nozzle to substrate distance. The temperature is differed between 350°C to 450°C. The structural and optical qualities were studied through physical investigation. According to XRD, the films have a hexagonal crystal structure. A scanning electron microscope reveals the material's uniform deposition &adhesion across a glass substrate. A direct band gap of about 2.4 to 2.6 eV was obtained for different temperatures. [ABSTRACT FROM AUTHOR]

To obtain ZrO2 and ZrO2+N2 thin films was used magnetron sputtering in radio frequency mode in a 10-6 mbar high vacuum deposition chamber. Silicon and carbon substrates measuring 12x15mm were used for deposition. The used magnetron system was composed of a single water-cooled cathode, provided with one circular targets of ZrO2 (2 mm thick and 50 mm in diameter) of high purity (99.95%). TDS Analysis of the films was performed. The desorbed species were observed with a QMG 220 Mass spectrometer provided with a W filament. It can be observed that in the case of the ZnO2 film, nitrogen desorption registers two maxima with signal intensity of 9.7x10-12 and 9.0x10-12, reached after 2000s and 4900s respectively. In the case of ZrO2+N2 film, nitrogen desorption shows a pronounced maximum with a signal intensity of 2.4x10-11 reached after 6000s. The topology the ZrO2 and ZrO2+N2 samples deposited on Si substrates have been investigated by scanning electron microscopy (SEM) using a FEI Inspect S scanning electron microscope (Hillsboro, Oregon, OR, USA) in high-vacuum modes. For the ZrO2 deposition, the surface appears to have grain-like topology, with a mean dimension of around 150 nm. These structures do not appear for the ZrO2+N2 deposition. Instead, for the ZrO2+N2 sample, small blisters (between 300 nm and 1.000nm) have formed on the surface, as a consequence of injecting N2 during the deposition. Cross-section measurements were also performed to establish the layer thickness. The ZrO2 sample has a measured thickness of 1950nm, while the introduction of N2 gas for the ZrO2+N2 sample had a poisoning effect on the magnetron target that led to a decrease (5 times) in deposition rate, giving this sample a final thickness of 365nm (compared to 1950nm) for the same deposition The crystalline structure was investigated using X-Ray Diffraction (XRD) method. The experimental set-up was composed of a diffractometer equipped with a Cu-Kα X-ray sourse, with a specific wavelength of 0.154nm, in a Bragg-Bretano type geometry. In this way, a crystalline phase corresponding to ZrO2 with a group symmetry Fm-3m (225)-face centered cubic was identified. At the same time, it is observed that the films deposited in the reactive atmosphere show a pronounced amorphization, this most likely being due to the retention of nitrogen which leads to the modification of the network parameters. [ABSTRACT FROM AUTHOR]

The present work includes the synthesis of zinc selenium telluride ZnSe1-xTex (0 ≤ x ≤ 1) ternary compound and its deposition in the form of thin films having thickness 200nm using thermal evaporation technique under high vacuum. The synthesized material ZnSe1-xTex thin films are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-VIS-NIR, and Raman spectroscopic measurements. The structural measurements reveal that the deposited thin films of ZnSe1-xTex material are polycrystalline, whose crystallinity decreases with concentration of tellurium material in thin films. The morphology measurement of films shows that the surface of films is smooth and particles are approximately spherical. The optical band gap estimated from the optical transmission spectra of the films is found to decrease with tellurium concentration. Peak shift is found towards red region with tellurium concentration in the films in Raman spectroscopic measurements. The obtained results are analyzed for application of ZnSe1-xTex thin films. [ABSTRACT FROM AUTHOR]

Poly(p-phenylenediamine- co–o-aminophenol) nanostructure thin film [PpPDoAP]TF was synthesized and prepared as a thin film with ≅ 100 ± 2 nm using the spin-coating method. Different characterization techniques for [PpPDoAP]TF like FTIR, UV–Vis spectroscopy, and optical properties have been studied. The resulted x-ray diffraction (XRD) and scanning electron microscope (SEM) data have been employed to study interface composites. Density function theory (DFT) was used for optimization by DMol3 and CASTEP. Spectroscopic and structural characteristics for the thin film have confirmed the chemical composition and XRD observations revealed the same crystal structure. Combined between experimental and TDD-DFT data, the average crystallite size and composite interface are 71.87 nm and orthorhombic symmetry (a = 7.38(2); b = 18.09(6); c = 26.09(4) Å and α = β = γ = 90°) with space group (Pmcn) for the thin film. It is found that the calculated energy gap by DFT and experimental method are 2.523 and 2.504 eV, respectively. The electronic transition of [PpPDoAP]TF has direct allowed transition. Besides, the optoelectrical parameters have been calculated for the film like n(λ), k(λ), dielectric constant, and optical conductivity. CASTEP simulated values are consistent with the experimental values for optical parameters of [PpPDoAP]TF. The fabricated thin film can be used as a candidate material for optoelectronic devices and solar cells. [ABSTRACT FROM AUTHOR]

In this research work, a simple spray pyrolysis method was employed to synthesized gadolinium (Gd) doped titanium oxide (TiO2) thin film. The crystal structure and morphology of the sample was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). According to XRD measurements, no apparent crystal peak was observed. The thickness of the prepared film was found to be 228 nm from SEM observation. The optical transmittance and bandgap energy of the synthesized thin film was investigated by using UV-Vis spectroscopy. The high transmission of the thin film was found in the visible region. The optical bandgap energy of the prepared film was found to be 2.85 eV. The photocatalytic degradation of malachite green solution was studied. As a result of the photocatalytic experiment, the thin film could be used as an effective photocatalyst for malachite green dye. [ABSTRACT FROM AUTHOR]

In this work, we have modulated the structural, morphological, optical and thermoelectric properties of CZTS thin films (TFs) by controlling the concentration of tin atoms. The CZTS TFs were grown by simple chemical solution method by changing tin mole concentration from 0.5 mM to 2.0 mM (labeled as T1, T2, T3 and T4). XRD data have revealed the formation of best crystalline CZTS TF at 1.5 mM tin concentration because tin (Sn+4) atoms are placed its own lattice sites therefore achieved the best crystal quality of CZTS. Furthermore, the phase purity of CZTS TF was confirmed by Raman spectroscopy. The lattice vibration of CZTS TF were observed at 329 and 334 cm−1 with A 1g mode and 367 cm−1 with B(TO) mode. The strongest Raman CZTS vibrational mode was observed for sample T3 which supported our XRD data. SEM images demonstrated that the surface of grown CZTS thin films became smoother with increasing the mole concentration of tin atoms up to 1.5 mM because the density of CuS grains has minimum value for this sample. The optimum band gap of T1, T2, T3 and T4 samples was estimated to 2.23, 2.15, 1.91 and 1.82 eV respectively which also confirmed that sample T3 has band gap value very close to reported value. The Seebeck coefficient, electrical conductivity and power factor values were enhanced from (243–762 μV/°C), (21–152 S/cm) and (1.24 × 10−4- 8.82 × 10−2Wm−1K−2) with increasing the mole concentration of tin (0.5–1.5 mM) at measurement temperature 100 °C. [ABSTRACT FROM AUTHOR]

The present work encloses the deposition of three zinc selenide (ZnSe) thin films of thickness 175 nm, 243 nm, and 286 nm using thermal evaporation technique under a vacuum of 5 × 10−5 mbar. The deposited ZnSe thin films are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), surface profilometer, ultraviolet (UV)-visible (Vis)-near-infrared (NIR) spectrophotometer and Raman spectroscopic measurements. The structure and morphology measurements reveal that the deposited ZnSe material is nanocrystalline having a cubic structure whose crystallinity increases with an increase in film thickness/evaporation rate. The optical band gap estimated from the optical transmission spectra of the films is found to be 2.62 eV, 2.60 eV, and 2.57 eV, respectively, which decreases with an increase in film thickness. The estimation and polynomial curve fit analysis of refractive index, extinction coefficient, and dielectric constant indicates that these physical quantities are fifth-order polynomial function of wavelength. The obtained results are compared and analysed for justification and application of ZnSe thin films. [ABSTRACT FROM AUTHOR]

Copper doped nickel oxide (NiO:Cu) thin films were synthesized via electrodeposition technique. X-ray diffraction, Scanning Electron Microscope, UV–visible spectroscopy, Vibrating Sample Magnetometer techniques and electrochemical analysis were utilized for the study of the structural, morphological, optical, magnetic and cyclic voltammogram properties respectively of both undoped and doped NiO thin films. The crystallographic studies of the undoped and doped NiO thin films showed that they are polycrystalline with cubic structure. Surface morphology of both the undoped and doped thin films showed nanocrystalline grains with spherical shaped particles. The optical studies showed a decrease in band gap energy from 3.34 eV to 3.32 eV and finally to 3.20 eV for the undoped, 2% and 3% respectively. The refractive index peaked between 2.60 and 2.65 while the calculated extinction coefficient values of the doped thin films have significant variation in the visible and NIR range. The studies of magnetization saturation values were found to be 1.52E-4 and 2.29E-4 for 2% and 3% doped respectively with low remanence values. Electrochemical studies revealed good cyclic voltammograms of the deposited films. These values indicate that the electrodeposited Cu doped NiO thin films are good candidates for magnetic applications. Image 1 • Copper doped NiO thin films were synthesized by electrodeposition method. • X-ray diffraction analysis shows strong reflection with preferential plane orientation of (222). • Optical measurement shows a decrease in energy bandgap of NiO upon doped with copper. • Magnetic measurements show ferromagnetic properties. [ABSTRACT FROM AUTHOR]

The spin coating technique has been utilized to deposit good adhesion successfully and highly uniform [DPP-Zn(Cl) 2 (H 2 O) 2 ], [DPPA-Zn(Cl) 2 (H 2 O) 2 ] and [DPPA-Zn-MR(Cl)(H 2 O)] thin films. The fabricated film thicknesses ranged from 100 to 150 nm. The molecular structure characteristics of compounds have been investigated by FT-IR, 1H NMR, and FAB-Mass spectroscopic. The structural and morphological properties of [DPP-Zn(Cl) 2 (H 2 O) 2 ], [DPPA-Zn(Cl) 2 (H 2 O) 2 ] and [DPPA-Zn-MR(Cl)(H 2 O)] thin films were examined by X-ray diffraction (XRD), and scanning electron microscope (SEM), respectively. According to the density functional calculations (DFT) results, the interaction of the zinc complexes conforms to lose associations, the interaction energies for all complexes in the matrix. The bonding mechanism of the zinc complexes includes both σ-dative and π-back bonding components. The measured optical properties of [DPP-Zn(Cl) 2 (H 2 O) 2 ], [DPPA-Zn(Cl) 2 (H 2 O) 2 ] and [DPPA-Zn-MR(Cl)(H 2 O)] thin films such as transmittance (T), absorbance (A) and reflectance (R) in UV-vis-NIR spectrum has been used to calculate optical features at room temperatures. The electrophilicity index (ω) of this zinc complexes are ≅ 10.86–13.84. These are significant interesting quantum chemical characteristics. The transparency of the complexes is within the range of ≅ 85–90% in the visible range. The optical band gap (E go) of [DPP-Zn(Cl) 2 (H 2 O) 2 ], [DPPA-Zn(Cl) 2 (H 2 O) 2 ] and [DPPA-Zn-MR(Cl)(H 2 O)] thin films were estimated by DFT and they found to be 1.045, 0937 and 0.736 eV, respectively. The refractive index (n) and the single oscillator energy (E o) were discussed by the single oscillator Wemple–Didomenico (WD) model. The high accuracy of the novel zinc complexes along with its appropriate optical band gap enabled us to build an efficient visible-blind UV-photodetector, indicating its potential in optoelectronic applications. Image 1 • Synthesis of novel zinc complexes thin films by spin coating technique. • Characterization of these complexes by using XRD, SEM and DFT modeling. • n and E o discussed by the single oscillator Wemple–Didomenico (WD) model. • Novel zinc thin films can be used as optical switching, organic photovoltaics and solar cells. [ABSTRACT FROM AUTHOR]

Titanium silicon nitride (TiSiN) thin films were deposited on p-type c-Si (100) with different N 2 flow rate by using chemical vapor deposition (CVD) technique. The microstructure, phonon modes, mechanical properties and compositional study of TiSiN thin films were characterised by scanning electron microscope (SEM), X-ray diffraction (XRD), Raman spectroscopy, nanoindentation and X-ray photoelectron spectroscopy (XPS),respectively. The SEM images show increases in surface roughness with increasing of N 2 flow rate, however, improves the hardness and Young's modulus of TiSiN thin film. The XRD analysis reveals the presence of strain in TiSiN films. The estimated crystallites of TiSiN thin films was 7.51 and 7.39 nm for 40 and 100 sccm N 2 flow rate. The XPS reveals the presence of 20 at. % Si content at 40 sccm N 2 flow rate in the TiSiN film. To analyse the broad Raman spectra of TiSiN thin films, the peaks were convoluted into six individual Gaussian peaks. The quantitative and qualitative analysis XPS and Raman spectra of TiSiN thin films were carried out by using Origin 9.0 software. [ABSTRACT FROM AUTHOR]

Copper-containing thin films were synthesized by a citrate sol-gel method using ethylene glycol. The evolution of the shape and local atomic structure of the copper-containing fractal crystallites at different stages of growth was investigated by the combination of experimental and theoretical techniques. A surface morphological study of the deposited film samples was carried out using SEM. It revealed the evolution of the crystallite structures as a function of annealing temperature. To describe this mechanism diffusion-limiting aggregation and cluster-cluster models were used. X-ray absorption spectroscopy (XANES) was applied to show the dynamics of the local atomic structure of Cu ion and the copper oxidation state at different stages of crystallites formation. It was found that at temperatures up to 250 °C the Cu2Cl(OH)3 (atacamite phase) and chelate complex are formed. With temperature increases changes in the local atomic structure as well as in morphology take place and at 500 °C CuO formed. As a result of these processes, the fractal organization of the other level was observed. [ABSTRACT FROM AUTHOR]

A high transparent Cu doped ZnS thin films were successfully deposited by the spray pyrolysis method at different deposition times. X-ray diffraction (XRD) patterns showed that all films were monocrystalline with the wurtzite crystal structure. A small variation in the optical band gap for all films was observed, indicating that the variation of deposition time doesn't affect strongly the bandgap. The average crystallite size of prepared thin films was calculated using Scherrer's formula and found to be in the range 29–33 nm. The crystallite size and microstrain of samples were investigated. Raman scattering spectra indicate the presence of different phonon modes and different peaks of Photoluminescence spectra for all samples which confirmed the presence of the elements Zn, S, and Cu with a comparison to the previous reported work. Using scanning electron microscope (SEM) images of elaborated thin films show a spherical with agglomeration. UV–visible measurements revealed height transmittance in the visible range for all growth time. [Display omitted] • The influence of Deposition time on physical properties Cu doped ZnS thin films using spray pyrolysis. • The structural and optical study using XRD, Raman and photoluminescence of Cu doped ZnS thin films. • Optical properties demonstrate the use of the materials in Photovoltaic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Composite films of TiN/Ni3N/a-Si3N4were synthesized using the Mather-type plasma focus device with varying numbers of focus deposition shots (5, 15, and 25) at 0° and 10° angular positions. The composition and structural analysis of these films were analyzed by using Rutherford backscattering (RBS) and X-ray diffraction (XRD). Scanning electron microscope and atomic force microscope were used to study the surface morphology of films. XRD patterns confirm the formation of composite TiN/Ni3N/a-Si3N4films. The crystallite size of TiN (200) plane is 11 and 22 nm, respectively, at 0° and 10° angular positions for same 25 focus deposition shots. Impurity levels and thickness were measured using RBS. Scanning electron microscopy results show the formation of net-like structures for multiple focus shots (5, 15, and 25) at angular positions of 0° and 10°. The average surface roughness of the deposited films increases with increasing focus shots. The roughness of the film decreases at higher angle 10° and the films obtained are smoother as compared with the films deposited at 0° angular positions. [ABSTRACT FROM AUTHOR]

Zinc thin films were deposited onto porous silicon (PSi) substrates by dc sputtering using a Zn target. These films were then annealed under flowing (6 l/min) oxygen gas environment in the furnace at 600°C for 2 h. Porous silicon is used as an intermediate layer between silicon and ZnO films and it provides a large area composed of an array of voids. The PSi samples were prepared using photoelectrochemical method on n-type silicon wafer with (111) and (100) orientation. To prepare porous structures, the samples were dipped into a mixture of HF:ethanol (1:1) for 5 min with current densities of 50 mA/cm2, and subjected to external illumination with a 500 W UV lamp. The surface morphology and the nanorod structure of the ZnO films were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). We synthesized the ZnO nanorods with diameter of 80-100 nm without any catalysts or templates. The XRD pattern confirmed that the ZnO nanorods were of polycrystalline structure. The surface-related optical properties have been investigated by photoluminescence (PL) and Raman measurements at room temperature. Micro-Raman results showed that A1(LO) of hexagonal ZnO/Si(111) and ZnO/Si(100) have been observed at 522 cm-1 and 530 cm-1, respectively. PL spectra peaks are clearly visible at 366 cm-1 and 368 cm-1 for ZnO film grown on porous Si(111) and Si(100) substrates, respectively. The PL spectral peak position in ZnO nanorods on porous silicon is blue-shifted with respect to that in unstrained ZnO (381 nm). [ABSTRACT FROM AUTHOR]

Nanocrystalline Se0.8Te0.2 films were grown on quartz substrates by using thermal evaporation technique. Structural and optical properties of as-grown and annealed samples were investigated with XRD, SEM and UV-visible spectroscopy. The x-ray diffraction pattern at room temperature shows that the sample are formed in single phase with monoclinic crystal symmetry having space group Cm. Surface morphology of the glass as-grown film was investigated via scanning electron microscopy (SEM). The typical diameter of as-grown nanocrystalline sample is found to be 50 nm, which is consistent with crystallite size calculated by XRD data using Scherrer equation. The UV-visible absorption spectra of the nanocrystals show that the optical band gap of as-grown and annealed samples are situated systematically in the range of 2.10 - 1.95 eV, which is quite larger than the bulk phase of the materials. The results have been explained on the basis of the close interplay between the structural and optical properties. [ABSTRACT FROM AUTHOR]

Abstract: Titanium nitride thin films were deposited on Si(100) substrates by using a low energy (2.3KJ) Mather-type plasma focus device. The composition of the deposited films was characterized by X-ray diffraction (XRD). The crystallite size has strong dependence on the numbers of focus shots. The crystallinity of TiN thin films is found to increase with increasing the number of focus shots. The effect of different number of focus shots on micro structural changes of thin films was characterized by Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). SEM results showed net-like structure for film deposited for 15 numbers of shots, which are elongated grains of Si3N4 in amorphous form embedded into TiN crystals. The average surface roughness was calculated from AFM images of the thin films. These results indicated that the average surface roughness increased for films deposited with increased number of focus shots. The least crystallite size and roughness are observed for film deposited with 25 focus shots. [Copyright &y& Elsevier]

Conducting polypyrrole (PPY) polymer thin films, prepared by the electrochemical process, were irradiated with 50 MeV Li3+ and 90 MeV C6+ ions at different fluences, ranging from 1011 to 1014 ions cm-2. The structural and electrical properties of the swift heavy ions (SHI) irradiated films were analyzed using X-ray diffraction (XRD), Scanning electron microscope (SEM), and conductivity measurement methods. XRD analysis of SHI irradiated PPY films shows that the crystallinity of the PPY films increases with increasing fluences of lithium ions, but tends to become amorphous at higher fluence. Carbon ions irradiations lead to polymer destruction and simultaneous amorphization even at low fluence. The SEM studies of irradiated PPY films show systematic change in their surface morphologies. The surface was smoother at lower fluence but craters were observed at higher fluence. The surface conductivity of films increases with increasing fluence of lithium ions, which also turn to the virgin film conductivity at higher fluence. It was found that carbon ions do not much affect the surface conductivity of PPY. [ABSTRACT FROM AUTHOR]