UV Induced Room Temperature Persistent Photocurrent in In$_{2}$O$_{3}$ Films

ORAL

Abstract

We have investigated the effects of UV irradiation on the electrical and optical properties of In$_{2}$O$_{3}$ thin films. These films were grown on sapphire substrate by RF sputtering. Hall effect measurements carried out to measure the carrier concentrations, n$_{c}$, show n-type conduction, with n$_{c} \quad \sim $ 2 $\times $ 10$^{18}$ cm$^{-3}$. We find that UV illumination on In$_{2}$O$_{3}$ films leads to a dramatic increase in the charge carrier concentration, approximately one order of magnitude, and that these elevated carrier densities persist at room temperature on a timescale of days. Consequently, we observe distinct changes in the optical absorption spectra. Also, we studied the decay of the charge carrier density to the pre-illuminated state as a function of temperature. We will discuss possible mechanisms for persistent photoconductivity in these In$_{2}$O$_{3}$ thin films.

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Authors

  • Raghava Panguluri

    Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201

  • Ambesh Dixit

    Wayne State University, Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Department of Physics and Astronomy, Wayne State University

  • C. Sudakar

    Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Wayne State University, Detroit, MI, Department of Physics and Astronomy, Wayne State University

  • Parashu Kharel

    Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201

  • Pushkal Thapa

    Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201

  • I.A. Avrutsky

    Department of Electrical and Computer Engineering, Wayne State University, Detroit, MI 48201

  • Alexander Efros

    Naval Research Laboratory, Center for Computational Materials Science,Naval Research Laboratory, Washington DC 20375, Center for Computational Material Science, Naval Research Laboratory, Washington DC, USA

  • R. Naik

    Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Wayne State University

  • Gavin Lawes

    Wayne State University, Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201, Department of Physics and Astronomy, Wayne State University

  • B. Nadgorny

    Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201