Determination of Carrier Type Doped from Metal Contacts to Graphene by Channel-Length-Dependent Shift of Charge Neutrality Points

Abstract

A method for determining the type of charge carrier, electron or hole, which is transferred from metal contacts to graphene, is described. The Dirac point is found to shift toward more negative (positive) gate voltages for electron (hole) doping by shortening of the interelectrode spacing. The shift of the Dirac point is accompanied by an enhancement of the electron-hole conductivity asymmetry. Experimentally determined carrier types may be explained in terms of the metal work functions modified by interactions with graphene.

12 pages, 4 figures

References in corpus (6)

• Ultrahigh electron mobility in suspended graphene
• Intrinsic and Extrinsic Performance Limits of Graphene Devices on SiO2
• Evidence of the role of contacts on the observed electron-hole asymmetry in graphene
• The Effect of Cluster Formation on Graphene Mobility
• Charge-density depinning at metal contacts of graphene field-effect transistors
• Transfer Characteristics in Graphene Field-Effect Transistors with Co Contacts

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• Reversible doping of graphene field effect transistors by molecular hydrogen: the role of the metal/graphene interface
• Experimental signature of bandgap opening in bilayer graphene at metal contacts
• Adsorbates as a charge-carrier reservoir for electrostatic carrier doping to graphene
• Contact resistance at planar metal contacts on bilayer graphene and effects of molecular insertion layers
• Superconducting Cavity-Based Sensing of Band Gaps in 2D Materials