• Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/boms/026/06/0613-0617

    • Keywords

       

      CdSe thin film; 𝐼–𝑉 characteristics; SCLC mechanism; localized traps.

    • Abstract

       

      The current (𝐼)–voltage (𝑉) characteristics of thermally evaporated CdSe thin films having thickness in the range 850–3000 Å and deposited within the substrate temperature of 303–573 K show nearly linear dependence at low voltage and afterwards a non-linear behaviour at higher voltage range. A detailed study of 𝐼–𝑉 curves in dark and under illumination clearly reveals the mechanism as ohmic at low voltage and that of trap limited space charge limited conduction (SCLC) at higher voltage. The transition voltage (𝑉𝑡) from ohmic to SCLC is found to be quite independent of ambient temperature as well as intensity of illumination. SCLC is explained on the basis of the exponential trap distribution in CdSe films. Trap depths estimated from the ln 𝐼 vs 103/T plots are found to be within 0.60–0.37 eV. Using the relevant SCLC theory, the carrier concentration, 𝑛0, total trap concentration, 𝑁t, and the ratio of free charge to trapped charge, 𝜃 , have been calculated and correlated with ambient temperature and intensity of illumination.

    • Author Affiliations

       

      Pradip Kr Kalita1 B K Sarma2 H L Das2

      1. Department of Physics, Guwahati College, Guwahati 781 021, India
      2. Department of Physics, Gauhati University, Guwahati 781 014, India
    • Dates

       
  • Bulletin of Materials Science | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.