17 research outputs found

    Study of Cu/In/Se/Se thin films prepared by the Stacked Elemental Layer (SEL) technique

    Get PDF
    CuInSe2 thin films have been grown on Corning glass and Si (100) substrates using stacked elemental layers (SEL) processing. The influence of substrate’s nature and substrate’s temperature were studied. X-ray diffraction and SEM measurements have shown that the films exhibit an excellent crystallinity and crystallize in a tetragonal structure. Scanning electron microscopy investigations have shown that the films consist in a structure with large grains in the range 80 – 200 nm. Increasing the deposition temperature from room temperature to 300 °C has lead to a change in the composition and morphology of the films. Characteristic peaks of the chalcopyrite structure such as (101), (211) and (311) were clearly observed for both layers upon annealing at 450°C as evidenced by X-ray diffraction study. The determined lattice parameters were a = 0.57725 (6) nm, b = 1.1621 (2) nm for sample prepared at room temperature and a = 0.57770 (4) nm, b = 1.1602 (1) nm for Ts = 300°C. The crystallographic structure of the CuInSe2 sample was analyzed by Rietveld analysis using X-ray powder diffraction data. UV-Vis-NIR Spectrophotometry was used to investigate the optical characteristics of different Cu/In/Se/Se thin layers in the spectral range between 300 – 2000 nm. The optical band-gap of our materials increases from 0.98 to 1.01 eV

    Characterization of in-situ Doped Polycrystalline Silicon Using Schottky Diodes and Admittance Spectroscopy

    Get PDF
    In this work, Schottky Au-Polycrystalline silicon diodes are successfully realised. The barrier height is around ФB = 0.74 eV as determined from Capacitance – Bias (C-V) characteristics. The depth profile of the apparent doping is deduced from these measurements. Its behaviour leads to the experimental profile. Moreover, the diode admittance measurements versus the frequency and the temperature at different biases show the possibility to use this device to characterise the electrical quality of the polycrystalline silicon

    DC and high-frequency conductivity of CuInSe2 bulk crystals

    No full text
    International audienceBulk crystals of CuInSe2 (CIS) were grown by vacuum fusion technique with specific proportions of Cu, In and Se. The studied samples, cut from the central part of the ingots, were first characterised by scanning electron microscopy, X-ray diffraction and energy dispersive spectroscopy. The conductivity of the crystals was investigated by using a contactless technique based on hyper-frequency microwave. The method consisted in measurements made in a rectangular resonance cavity at 9192 MHz. Conductivity has been also measured by conventional Van der Paw method and the values obtained, varied in the range [3.10-3-7.10-3]Ω-1cm-1, didn't show significant discrepancies between the two techniques

    DC and high-frequency conductivity of CuInSe2 bulk crystals

    No full text
    International audienceBulk crystals of CuInSe2 (CIS) were grown by vacuum fusion technique with specific proportions of Cu, In and Se. The studied samples, cut from the central part of the ingots, were first characterised by scanning electron microscopy, X-ray diffraction and energy dispersive spectroscopy. The conductivity of the crystals was investigated by using a contactless technique based on hyper-frequency microwave. The method consisted in measurements made in a rectangular resonance cavity at 9192 MHz. Conductivity has been also measured by conventional Van der Paw method and the values obtained, varied in the range [3.10-3-7.10-3]Ω-1cm-1, didn't show significant discrepancies between the two techniques
    corecore