Effect of Annealing Temperature on Structural, Photoluminescence and Photoconductivity Properties of ZnO Thin Film Deposited on Glass Substrate by Sol–Gel Spin Coating Method

  • Mohd. Mubashshir Hasan Farooqi
  • Rajneesh Kumar SrivastavaEmail author
Research Article


In this work, zinc oxide (ZnO) thin films have been deposited on glass substrate using a simple and inexpensive multi-step sol–gel spin coating method at annealing temperatures of 300, 400, 500 and 600 °C in an open atmosphere. The influence of annealing on structural, photoluminescence and photoconductivity properties of ZnO thin films has been systematically investigated. X-ray diffraction pattern reveals that all ZnO thin films are polycrystalline with hexagonal wurtzite structure. Scanning electron micrograph depicted the formation of ZnO nanofibrous structure. Photoluminescence properties of ZnO thin films have been investigated by photoluminescence spectroscopy at room temperature. Photoconductivity properties have been investigated in terms of several parameters such as voltage dependence of photocurrent and dark current as well as time-resolved rise and decay of photocurrent. The rise and decay spectra under periodic illumination show reproducible and stable photoresponse. The synthesized ZnO thin film seems to be having potential use in UV–Vis photodetectors.


Photoconductivity Photoluminescence ZnO Thin film Sol–gel XRD Fibrous root morphology 



The authors are thankful to National Center for Mineralogy and Petrology (NCEMP), University of Allahabad, for providing XRD and SEM facilities; SAIF-STIC, Cochin University of Science and Technology, Cochin, for providing UV–Vis, EDS and HRTEM facilities; SAIF, IIT Chennai, for providing fluorescence measurement. One of the authors M. M. Hasan Farooqi is grateful to UGC, New Delhi, for providing financial assistance as Senior Research Fellowship (SRF) under Maulana Azad National Fellowship (MANF) Scheme F1-17.1/2011/MANF-MUS-UTT-4185 (SA-III/website/January 02, 2012) during synthesis of this work (July 12, 2013, to July 11, 2016). The authors are also thankful to Mr. Rajkumar, Department of Electronics and Communication, University of Allahabad, for his help in formatting of manuscript.


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Copyright information

© The National Academy of Sciences, India 2019

Authors and Affiliations

  • Mohd. Mubashshir Hasan Farooqi
    • 1
  • Rajneesh Kumar Srivastava
    • 1
    Email author
  1. 1.Department of Electronics and CommunicationUniversity of AllahabadAllahabadIndia

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