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Electrical contacts to one- and two-dimensional nanomaterials

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Abstract

Existing models of electrical contacts are often inapplicable at the nanoscale because there are significant differences between nanostructures and bulk materials arising from unique geometries and electrostatics. In this Review, we discuss the physics and materials science of electrical contacts to carbon nanotubes, semiconductor nanowires and graphene, and outline the main research and development challenges in the field. We also include a case study of gold contacts to germanium nanowires to illustrate these concepts.

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Figure 1: Examples of nanomaterial-based devices.
Figure 2: Contact geometries.
Figure 3: Band alignment at metal/nanostructure interfaces.
Figure 4: Charge injection at metal–nanostructure contacts.
Figure 5: Formation of the different phases of nickel silicide.
Figure 6: Au–nanoparticle–Ge-nanowire contacts.
Figure 7: Opportunities and challenges for research and development.

Change history

  • 28 November 2011

    In the version of this Review originally published online, equation (2) appeared incorrectly. This has now been corrected in all versions of the Review

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Acknowledgements

F.L. acknowledges financial support from the Laboratory Directed Research and Development Program at Sandia National Laboratories, which is by operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy (contract DE-AC04-94-AL85000).

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Correspondence to François Léonard or A. Alec Talin.

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Léonard, F., Talin, A. Electrical contacts to one- and two-dimensional nanomaterials. Nature Nanotech 6, 773–783 (2011). https://doi.org/10.1038/nnano.2011.196

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