Imaging surface potential variations in graphene on Si-face SiC

ORAL

Abstract

Kelvin Probe Microscopy (KPM) is used to map the surface potential of graphene monolayers grown on the Si-face of SiC wafers. Variations in surface potential are observed which are not correlated to any topographical features on the graphene surface. The observed variation in surface potential has an RMS value of $\sim $17 meV, and correspond to variations in carrier concentration on the order of 10$^{10}$-10$^{11}$ cm$^{-2}$. We will discuss the implications of these measurements on interpretation of transport data on ungated graphene on Si-face SiC.

*This work was supported by the University of Maryland MRSEC

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Authors

  • Alexandra Curtin

    • Materials Research Science and Engineering Center and Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland

  • Michael S. Fuhrer

    • University of Maryland
    • Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland College Park
    • Materials Research Science and Engineering Center and Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland

  • J. L. Tedesco

    • Code 6882 NRL
    • U.S. Naval Research Laboratory, Code 6800, Washington, DC 20375

  • R. L. Myers-Ward

    • U.S. Naval Research Laboratory, Code 6800, Washington, DC 20375

  • P. M. Campbell

    • Code 6876 NRL
    • U.S. Naval Research Laboratory, Code 6800, Washington, DC 20375

  • C. R. Eddy

    • U.S. Naval Research Laboratory, Code 6800, Washington, DC 20375

  • D. K. Gaskill

    • U.S. Naval Research Laboratory, Code 6800, Washington, DC 20375