Electronic Properties of Clean Au-Graphene Contacts

Abstract

The effects of Au grains on graphene conduction and doping are investigated in this report. To obtain a clean Au-graphene contact, Au grains are deposited over graphene at elevated temperature and in high vacuum, before any chemical processing. The bulk and the effective contact resistance versus gate voltage demonstrate that Au grains cause p-doping in graphene. The Fermi level shift is in agreement with first principles calculations, but the equilibrium separation we find between the graphene and the top-most Au layer is larger than predicted. Nonequilibrium electron transport displays giant-phonon thresholds observed in graphene tunnel junctions, demonstrating the tunneling nature of the contact, even though there are no dielectrics involved.

11 pages, 4 figures

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Cited by in corpus (6)

• The role of contact resistance in graphene field-effect devices
• Atomic-scale model for the contact resistance of the nickel-graphene interface
• Do CVD grown graphene films have antibacterial activity on metallic substrates?
• Contact doping, Klein tunneling, and asymmetry of shot noise in suspended graphene
• Carrier density modulation in graphene underneath Ni electrode
• Making Consistent Contacts to Graphene: Effect of Architecture and Growth Induced Defects