Papers by Keyword: Nickel Thin Film

Abstract: The synthetic NiO nanostructures have been grown using thermal wet oxidation of metallic Ni thin films on ITO/glass by RF sputtering. The deposited Nickel thin films layer were oxidized in stream atmosphere at varying temperatures range of 400 °C to 700 °C inside furnace. Structural, surface morphology, electrical and the optical properties of NiO nanostructure were analysed by X-ray diffraction (XRD), Field effect scanning electron microscope (FESEM), energy dispersive X-ray (EDX), hall effects measurements and UV-Visible spectroscope measurements. XRD analysis proves that the NiO nanostructure has a cubic structure with orientation of the most intense peak at (200), and the film prepared 600 °C shows a better crystalline quality. FESEM and AFM results also prove that by increasing the oxidation temperature, the dimensions and roughness of the NiO nanoparticle thin layer increases. Also the oxidation rate appears higher. The optimum temperature for synthesizing high quality NiO with great stoichiometric and crystalline property was determined to be at 600 of wet oxidation. EDX results reveals only O and Ni present in the treated samples, indicating a pure NiO composition obtained. From UV-Vis absorption spectroscope of Tauc’s relationship, the bang gap was observed to increase with temperature at range of 3.29 – 4.09 eV. The effect of annealing was highlighted on the tunability of electrical property Ni thin films with both n-type and p-type behavior NiO as determine from hall measurement. The observed tunability of NiO thin film will ease way toward p-n homojunction realization for optoelectronic device applications of short wave length that involves photodetectors and LEDs

Abstract: Carbon Nanofibers (CNF) layers were synthesized nickel-based thin-films on flat fused silica substrates. CNF synthesis was performed via thermal catalytic chemical vapor deposition of ethylene using nickel as metal catalyst. Different underlayer metal thin films, viz. titanium, tantalum and titanium-tungsten were tested in order to obtain stable and well-attached CNF films on fused silica substrates. It is found in case of titanium CNFs are formed on the nickel, but due to severe Ni/Ti inderdiffusion the titanium film looses its adhesive function, as a consequence of which the formed CNF film detaches from the substrate. The use of tantalum or titanium-tungsten as adhesion layer resulted in stable and well-adhered CNF films on fused silica substrates, of which the morphology can be controlled by the growth time.