Electronic Transport Properties of Epitaxial ZnO Films by Electron Dephasing and Mobility Spectrum Analysis

ORAL

Abstract

Epitaxial ZnO films were grown by pulsed laser deposition on (111) Si substrates with bixbyite oxide buffers. Carrier transport properties were investigated using Hall measurements (4--300 K) under magnetic fields of 0--10 T, indicating mobility up to 113 cm$^{2}$/Vs. A diffusive Fermi surface (DFS) model incorporating electron dephasing theories was used to fit the abnormally positive magneto-conductivity observed below 150 K. Quantitative mobility spectrum analysis revealed the presence of a hole group at lower mobility accompanying the major electron group. Geometric distribution of the conducting groups was examined by capacitance-frequency experiments, while both temperature-dependent photoluminescence and mobility fitting confirmed a donor binding energy of $\sim$60 meV.

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Authors

  • Kui Zhang

    • Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109

  • Wei Guo

    • Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109

  • Michael Katz

    • Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109

  • Tassilo Heeg

    • Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853

  • Darrell Schlom

    • Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853

  • Mingrui Hao

    • Department of Physics, Shanghai Jiao Tong University, Shanghai 200240, China

  • Wenzhong Shen

    • Department of Physics, Shanghai Jiao Tong University, Shanghai 200240, China

  • Xiaoqing Pan

    • Dept. of Mater. Sci. \& Eng., Univ. of Michigan, Ann Arbor, MI
    • Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109
    • University of Michigan