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Nano-crystalline Titanium Nitride (TiN) thin films were deposited on glass substrates by reactive DC magnetron sputtering in the presence of a supported discharge (dc triode magnetron sputtering). A hot thermionic filament which was negatively biased is kept between the target and substrate, and was used to sustain the discharge at much lower pressures. The TiN films deposited at room temperature (RT) were annealed at different temperatures of 373, 473 and 573 K in a high vacuum for 1 h. The films were characterized for their morphological, structural, micro-structural, optical and electrical properties. RT deposited titanium to nitrogen ratio was found to be 1:1 which has been confirmed by EDAX. XRD studies showed that the as-deposited TiN thin film were amorphous in nature and transformed to a nano-crystalline structure with increasing annealing temperatures. The crystallite growth of TiN thin films started around 373 K onwards, and it became a face-centered cubic structure with a preferred orientation along the (111) plane. The band gap of TiN thin films was found to increase from 2.7 to 3.2 eV with an increase in the annealing temperature. The photoluminescence spectrum of TiN thin films indicates a broadening of emission wavelength in the visible region with a maximum emission peak around 360 nm. The electrical resistivity of TiN thin films was found to drop significantly from 1800 to 400 µΩ cm with an increase in the annealing temperature. The AFM micrographs of annealed TiN thin films show uniform surface pattern associated with a large accumulation of fine grains. Through this work, it has been demonstrated that it is possible to achieve the required physical properties of TiN films at lower annealing temperatures by the supported discharge dc magnetron technique compared to other sputtering techniques. [ABSTRACT FROM AUTHOR]

Zirconium oxide (zirconia) powder has been synthesized by co-precipitation method. The structural characterization of prepared sample was obtained by X-ray diffraction and showed monoclinic phase. Further surface morphology was confirmed by scanning electron microscopy (SEM). The frequency dependence of dielectric constant, dielectric loss, and impedance of the sample was investigated at room temperature. The obtained results partially motivated for alternative silicon based on devices. [ABSTRACT FROM AUTHOR]

NiO-Ag thin films were deposited on Corning 7059 glass substrates by DC reactive magnetron sputtering technique and investigated the substrate temperature ( T) dependent properties of NiO-Ag thin films. X-ray diffraction results showed that crystalline films can be obtained at high T and all films have a preferred crystal growth texture with face centered cubic ( f) structure and was also confirmed by Raman studies. The grain size, transmittance, band gap, mobility and carrier concentrations were increased with T. Room temperature deposited films have an average roughness around 6.9 nm where as increment of T resulted in increased roughness up to 14 nm with nanocrystalline morphology. The optimum substrate temperature to obtain NiO-Ag films was found to be 200°C. It was found that with increasing the T, resistivity of the films was significantly decreased. [ABSTRACT FROM AUTHOR]

LaBaMnO (LBMO) thin films were deposited on Si substrates at various substrate temperatures (Ts) ranging from 823 K to 1023 K using electron beam evaporation (EBE), and studied the structural, composition and electrical properties of the films as a function of deposition temperature were studied. X-ray diffraction (XRD) studies revealed the epitaxial growth in the films. The surface morphology of the films were characterized by atomic force microscopy (AFM). The elemental composition analysis investigated by energy dispersive spectroscopy (EDS) confirmed the stoichiometry. The films deposited at higher substrate temperatures (1023 K), showed lower resistivity with a higher temperature coefficient of resistance (TCR). A TCR of 4.09%/K obtained in the present investigation is suitable for bolometric applications near to the room temperature. [ABSTRACT FROM AUTHOR]

Nanocrystalline Zn1-xMnxS films (x=0.04, 0.08 and 0.12) were deposited on glass substrates at 400 K using a simple resistive thermal evaporation technique. All the deposited films were characterized by chemical, structural, morphological, optical and magnetic properties. Scanning electron microscopy and atomic force microscopy studies showed that all the films investigated were in nanocrystalline form with the grain size lying in the range 10–20 nm. All the films exhibited cubic structure and the lattice parameters increase linearly with composition. The absorption edge shifted from the higher-wavelength region to lower wavelengths with increase in Mn concentration. The magnetization increased sharply with increase of the Mn content up to x=0.08 and then decreased with further increase of the Mn content. Particularly, Zn0.92Mn0.08S concentration samples show a weak ferromagnetic nature, which might be the optimum concentration for optoelectronic and spintronic device applications. [ABSTRACT FROM AUTHOR]

Thin films of molybdenum trioxide were deposited on glass substrates employing direct current (DC) magnetron sputtering by sputtering of molybdenum at different oxygen partial pressures in the range 8 × 10−5–1 × 10−3 mbar and at a substrate temperature of 473 K. The glow discharge characteristics of magnetron cathode target of molybdenum were studied. The influence of oxygen partial pressure on the structural and optical properties of molybdenum trioxide films was investigated. The films formed at an optimum oxygen partial pressure of 2 × 10−4 mbar were polycrystalline in nature with orthorhombic α- phase and an optical band gap of 3.16 eV. The refractive index of the films formed at an oxygen partial pressure of 2 × 10−4 mbar decreased from 2.08 to 1.89 with increase of wavelength from 450 to 1,000 nm, respectively. [ABSTRACT FROM AUTHOR]