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    The effect of substrate temperature on the structural, optical and electrical properties of vacuum deposited ZnTe thin films
    (2009) Rao, G.K.; Bangera, K.V.; Shivakumar, G.K.
    The present paper reports the effect of substrate temperature on the structural, optical and electrical properties of vacuum deposited zinc telluride (ZnTe) thin films. X-ray diffraction (XRD) analysis of the films, deposited on glass substrates, revealed that they have cubic structure with strong (111) texture. Room temperature deposits are tellurium rich and an increase in the substrate temperature up to 553 °K results in stoichiometric films. Electrical conductivity has been observed to increase with the increase in substrate temperature, accompanied by increase in the carrier concentration and the mobility of the carriers. The optical bandgap energy and the thermal activation energy of the films have also been evaluated. © 2009 Elsevier Ltd. All rights reserved.
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    Study of the aluminium oxide doped zinc oxide thin films prepared by thermal evaporation technique
    (2012) Palimar, S.; Banger, K.V.; Shivakumar, G.K.
    The present study reports the observations made on investigations carried out to study structural, optical and electrical properties of aluminium oxide doped ZnO thin films obtained by thermal evaporation technique. Films obtained are found to be amorphous in nature with smooth and continuous surface. Room temperature conductivity of the film is found to be 5x10 3 U -1 cm -1 with visible region transmittance of above 95%. The optical energy gap of the film is found to be 3.25 eV. From the calculations of activation energy, it is observed that the doped ZnO film has two donor levels, one at 142 meV and other at 43 meV. A detailed analysis of the result is reported. © 2012 Asian Network for Scientific Information.
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    Study of the doping of thermally evaporated zinc oxide thin films with indium and indium oxide
    (Springer Nature, 2013) Palimar, S.; Bangera, K.V.; Shivakumar, G.K.
    The present paper reports observations made on investigations carried out to study structural, optical and electrical properties of thermally evaporated ZnO thin films and their modulations on doping with metallic indium and indium oxide separately. ZnO thin film in the undoped state is found to have a very good conductivity of 90 ?–1 cm–1 with an excellent transmittance of up to 90 % in the visible region. After doping with metallic indium, the conductivity of the film is found to be 580 ?–1 cm–1, whereas the conductivity of indium oxide-doped films is increased up to 3.5 × 103 ?–1 cm–1. Further, the optical band gap of the ZnO thin film is widened from 3.26 to 3.3 eV when doped with indium oxide and with metallic indium it decreases to 3.2 eV. There is no considerable change in the transmittance of the films after doping. All undoped and doped films were amorphous in nature with smooth and flat surface without significant modifications due to doping. © 2012, The Author(s).
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    Effect of annealing on the properties of Bi doped ZnO thin films grown by spray pyrolysis technique
    (Academic Press, 2014) Sadananda Kumar, N.; Bangera, K.V.; Shivakumar, G.K.
    The effect of annealing temperature on the structural, optical and electrical properties of transparent and conducting Bi doped ZnO (BZO) films deposited on glass substrate by spray pyrolysis technique was investigated. The BZO thin films were annealed in the temperature range from 450 °C to 550°C for 4 h in air atmosphere. The grain size of the BZO films increased with increasing annealing temperature. The annealed BZO films were electrically stable and there was a drastic change in the electrical conductivity after annealing. The films annealed at 500°C showed better conductivity and optical transmittance. © 2014 Elsevier Ltd. All rights reserved.