Hole doping in VO$_{2}$ thin films

ORAL

Abstract

Chemical doping has been used to modulate the metal-semiconductor transition in VO$_{2}$ extensively. Here, we investigated the effect of aliovalent Al$^{3+}$ doping in VO$_{2}$ thin films on the Metal-Semiconductor Transition (MST) in comparison with the effect of isovalent Mn$^{4+}$ doping. Raman spectroscopy and x-ray diffractometry were used to confirm the monoclinic phase and estimate the lattice strain caused by the doping. The concentration and the valence state of the dopants observed by XPS will be discussed. The Al$^{3+}$ ions are expected to introduce holes into the conduction band of the VO$_{2}$, and the evidence for hole doping by Al$^{3+}$ was observed by Hall effect measurements. This effect has not been reported previously. Both types of dopants were found to increase the change of the resistivity across the MST, and they also shifted the T$_{\mathrm{MST}}$.

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Authors

  • Salinporn Kittiwatanakul

    Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA

  • Ryan Comes

    Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA

  • Yuhan Wang

    Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA, Univ of Virginia

  • Stuart Wolf

    Department of Physics and Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA, Univ of Virginia, University of Virginia, Department of Materials Science and Engineering, Department of Physics, Charlottesville, VA

  • Jiwei Lu

    Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA, University of Virginia, University of Virginia, Department of Materials Science and Engineering, Charlottesville, VA