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The effects of ambient helium gas pressure on the optical, structural and electrical properties of the diamond-like carbon thin films from camphoric carbon soot target, deposited by pulsed laser deposition have been studied. Optical gap and electrical resistivity are found to increase initially at low ambient pressure of 0.008 Torr. With further increase in ambient pressure up to 2.6 Torr, optical gap and electrical resistivity are found to decrease. The films are characterized for their structural properties using different spectroscopic techniques such as, XPS, Raman, and FTIR spectroscopy, and surface morphological techniques like SEM and AFM, and their electrical properties using four-probe resistance measurement.

Thin nanocrystalline Cu films (< 1 μm) are deposited on a glass substrate using an improved electroless plating technique. The deposition course of the Cu film is illustrated by the variation of surface morphology with different deposition time. The results show that a more uniform and continuous nanocrystalline Cu film with very small nodules can be formed on a glass substrate at the deposition time over 1 min. The roles of SDBS as an additive in the bath are also discussed. According to the relation of the film thickness and the deposition time, it is obvious that the film thickness nearly linearly varies with the deposition time in the present work. An enhanced (111) texture with the diffraction intensity ratio (I₍₁₁₁₎/I₍₂₀₀₎) of about 4.0 and the very fine grain size of 15–28 nm determined by X-ray results has been observed. The variations of the resistivity show that it is strongly affected by the film thickness and grain size.

Nominal compositions of Ni_xTi_1-xFe₂O_5-δ (x = 0, 0.2, 0.4, 0.6, 0.8 and 1) were prepared by a solid state reaction using stoichiometric amounts of Fe₂O₃/TiO₂ system and NiO as a dopant. The effects of small substitution of Ni ions on the electrical and structural properties were studied for the above system. The X-ray diffraction patterns revealed that the ferroelectric phase of iron titanate and the spinel ferrite phase of Ni-ferrite having a single phase at x = 0 and 1, respectively. The substitution of Ni ions increases the average value of lattice constant a_av. Solid–solid interaction took place between the ternary oxides at 1200°C for 4 h yielding a new phase of NiTiO₃. The presence of the three phases was confirmed by X-ray diffraction technique. The resultant compositions have nanocrystallites with average crystalline size "D_av" in the range 100–300 nm. The DC electrical resistivity ρ, Curie temperature T_C and activation energies for electric conduction around T_C region increase as Ni ion substitution increases. The ferrite samples have a semiconductor behavior where electrical resistivity ρ decreases on increasing temperature. The activation energy for electrical conduction was affected by both the ratio "ferroelectric/ferrite" and the position of the Curie temperatures in the compositions depending on the (Ni, Ti) to Fe ratio.

ZnO thin films were prepared on silicon (001) and corning glass substrates using Pulsed laser deposition (PLD) technique with different oxygen pressures. The microstructure, crystallinity, and resistivity of the films depend on the oxygen pressure used. The effects of the films grown at room temperature and at 500°C with different oxygen pressures have been investigated by analyzing the optical and electrical properties of the film. The XRD analysis showed that the high intensity of c-axis orientation of ZnO thin films was obtained under high oxygen pressure and this leads to greater electrical and optical properties. By applying high pressure oxygen, the resistivity value was decreased and optical transmittance became higher in the visible region. The surface morphology of the films showed that the smooth surface was observed without any cracks.

Indium tin oxide (ITO) nanoparticles were synthesized by co-precipitation method using ammonia as a precipitator in absence/presence of various surfactants (LABS and Triton X-100). The synthesized nanoparticles were investigated by scanning electron microscopy, resistance measurement, photoluminescence (PL) spectroscopy and X-ray diffractometry (XRD) techniques. The XRD patterns of nanoparticles were also studied by Rietveld refinement method for calculation of crystallite size, micro-strain and lattice parameter. The results indicate that by application of LABS and Triton X-100 as surfactant the particle size was increased. Two luminescence bands were observed in PL spectra of ITO nanoparticles with the excitation energy lower than their band gaps. It was found that the ratios of luminescence bands have relation with resistances and colors of ITO nanoparticles. In addition, the band structure of ITO nanoparticles was described considering the obtained results.

Molybdenum thin films were sputter deposited under different conditions of DC power and chamber pressure. The structure and topography of the films were investigated using AFM, SEM and XRD techniques. Van der Pauw method and tape test were employed to determine electrical resistivity and interfacial strength to the substrate, respectively. All the films are of sub-micron thickness with maximum growth rate of 78 nm/min and crystallite size in the range of 4 to 21 nm. The films produced at high power and low pressure exhibit compressive residual strains, low electrical resistivity and poor adhesion to the glass substrate, whereas the converse is true for films produced at high pressure.

Cadmium sulfide (CdS) and aluminum-doped zinc oxide (Al:ZnO) thin films are used as buffer layer and front window layer, respectively, in thin film solar cells. CdS and Al:ZnO thin films were produced using chemical bath deposition (CBD) and sol–gel technique, respectively. For CBD CdS, the effect of bath composition and temperature, dipping time and annealing temperature on film properties was investigated. The CdS films are found to be polycrystalline with metastable cubic crystal structure, dense, crack-free surface morphology and the crystallite size of either few nanometers or 12–17 nm depending on bath composition. In case of CdS films produced with 1:2 ratio of Cd and S precursors, spectrophotometer studies indicate quantum confinement effect, owing to extremely small crystallite size, with an increase in E_g value from 2.42 eV (for bulk CdS) to ~ 3.76 eV along with a shift in the absorption edge toward ~ 330 nm wavelength. The optimum annealing temperature is 400°C beyond which film properties deteriorate through S evaporation and CdO formation. On the other hand, Al:ZnO films prepared via spin coating of precursor sols containing 0.90–1.10 at.% Al show that, with an increase in Al concentration, the average grain size increases from 28 nm to 131 nm with an associated decrease in root-mean-square roughness. The minimum value of electrical resistivity, measured for the films prepared using 0.95 at.% Al in the precursor sol, is ~ 2.7 × 10^-4 Ω ⋅ cm. The electrical resistivity value rises upon further increase in Al doping level due to introduction of lattice defects and Al segregation to the grain boundary area, thus limiting electron transport through it.

PtO_x films were deposited by direct current (DC) reactive magnetron sputtering in Ar/O₂ mixture atmosphere at substrate temperatures ranging from 200^∘C to 400^∘C. The influence of substrate temperature on the structure, morphology, composition, electrical resistivity and infrared emissivity of PtO_x films was studied. The X-ray photoelectron spectroscopy (XPS) and grazing incidence X-ray diffraction (GIXRD) results revealed that the as-deposited amorphous PtO_x films were mainly composed of PtO and PtO₂ phases. It was found that with the increase in the substrate temperature, the proportion of PtO phase in the films increased, while the electrical resistivity and infrared emissivity of the films decreased with the increasing substrate temperature.

A carbon precursor film was formed on a titanium plate by a hydrothermal method using glucose, and an amorphous film was obtained by carbonization at 400^∘C under an Ar atmosphere. The morphology and composition of the surface was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the interface contact resistance (ICR) under different pressures by simulating the working mode of the fuel cell. The corrosion resistance of amorphous carbon coatings was tested by simulating the proton exchange membrane fuel cells (PEMC). The amorphous coating showed excellent interfacial conductivity and great corrosion resistance, with high potential application in bipolar plates of PEMFCs