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COAR Access Rights: metadata only accessSubject: Nanosandwiched

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    Article
    Citation - WoS: 14
    Citation - Scopus: 15
    Investigation of the Physical Properties of the Yb Nanosandwiched Cds Films
    (Elsevier Science Sa, 2018) Abed, Tamara Y.; Qasrawi, A. F.; Al Garni, S. E.
    In this study, the effects of the sandwiching of a 70 nm thick ytterbium film between two layers of CdS on the structural, compositional, optical and electrical properties are investigated. The X-ray diffraction, scanning electron microscopy, energy dispersion X-ray, visible light spectroscopy and impedance spectroscopy techniques are employed to achieve these effects. It was observed that, the nanosandwiching of Yb between two 500 nm thick films of CdS enhances the crystalline nature of the films without altering the lattice parameters. Particularly, the grain size is increased by 25%, the strain, the defect density and the stacking faults are reduced by 31.5%, 43.7% and 25%, respectively. Optically, the Yb nanosandwiching is observed to enhance the visible light absorbability by at least 2.7 times of the whole range and by 8 times at 1.64 eV. The enhancement of the absorbability is associated with shrinking in the band gap and more interband states. In addition, an increase in the real part of the dielectric constant by 54% is observed when Yb was nanosandwiched in the CdS structure. The modeling of the imaginary part allowed exploring the electron-plasmon interaction parameters. A remarkable increase in the drift mobility from 281 to 996 cm2/Vs associated with plasmon frequency enhancement from 0.84 to 1.38 GHz was determined upon Yb nanosandwiching. The effectiveness of this modeling was verified from the impedance spectra in the frequency domain of 0.01-1.80 GHz, which revealed wave trapping property of ideal values of return loss at notch frequency of 1.35 GHz. Furthermore, the electrical resistivity measurements on the studied samples have shown that the presence of Yb reduced the electrical resistivity and shifts the donor level closer to the conduction band of CdS. The studies nominate the nanosandwiched CdS for use in optical and microwave technologies as dual devices. (C) 2017 Elsevier B.V. All rights reserved.
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    Article
    Citation - WoS: 3
    EFFECT OF Y, Au AND YAu NANOSANDWICHING ON THE STRUCTURAL, OPTICAL AND DIELECTRIC PROPERTIES OF ZnSe THIN FILMS
    (Natl inst R&d Materials Physics, 2019) Qasrawi, A. F.; Taleb, M. F.
    In this article, we report the effects of insertion of yttrium, gold and yttrium-gold (YAu) metallic nano-slabs on the structural, optical and dielectric properties of ZnSe thin films. The ZnSe thin films which are prepared by the thermal evaporation technique under vacuum pressure of 10-5 mbar exhibit hexagonal structure. While the insertion of the 70 nm thick Y layers does not alter the lattice parameters and stress values, the Au and YAu layers increased the lattice parameters along the a- and c-axes and decreased the stress values. In addition, the insertion of these metallic layers slightly alters the value of the energy band gap and increases the width of the interbands. The light absorbability are increased by 1.4, 2.0 and 2.4 times upon insertion of Y, Au and YAu, slabs, respectively. On the other hand, the dielectric and optical conductivity analyses has shown that the use of the YAu stacked metal layers increases the real part of the dielectric constant, the optical conductivity, the drift mobility and extended the plasmon frequency range from 35.1 to 254.0 (Omega cm)(-1), from 1098 to 1766 cm(2)/vs and from 0.94-3.11 GHz to 2.13-4.83 GHz, respectively. The insertion of the two stacked metallic layers between two layers of ZnSe makes the ZnSe more appropriated for thin film transistor technology.
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    Article
    Citation - Scopus: 3
    Effect of Y, Au and Yau Nanosandwiching on the Structural, Optical and Dielectric Properties of Znse Thin Films
    (S.C. Virtual Company of Phisics S.R.L, 2019) Qasrawi,A.F.; Taleb,M.F.
    In this article, we report the effects of insertion of yttrium, gold and yttrium-gold (YAu) metallic nano-slabs on the structural, optical and dielectric properties of ZnSe thin films. The ZnSe thin films which are prepared by the thermal evaporation technique under vacuum pressure of 10-5 mbar exhibit hexagonal structure. While the insertion of the 70 nm thick Y layers does not alter the lattice parameters and stress values, the Au and YAu layers increased the lattice parameters along the a- and c-axes and decreased the stress values. In addition, the insertion of these metallic layers slightly alters the value of the energy band gap and increases the width of the interbands. The light absorbability are increased by 1.4, 2.0 and 2.4 times upon insertion of Y, Au and YAu, slabs, respectively. On the other hand, the dielectric and optical conductivity analyses has shown that the use of the YAu stacked metal layers increases the real part of the dielectric constant, the optical conductivity, the drift mobility and extended the plasmon frequency range from 35.1 to 254.0 (Ωcm)−1, from 1098 to 1766 cm2/Vs and from 0.94-3.11 GHz to 2.13-4.83 GHz, respectively. The insertion of the two stacked metallic layers between two layers of ZnSe makes the ZnSe more appropriated for thin film transistor technology. © 2019, S.C. Virtual Company of Phisics S.R.L. All right reserved.