title: Conductance anisotropy in epitaxial graphene sheets generated by substrate interactions.
abstract: We present the first microscopic transport study of epitaxial graphene on SiC using an ultrahigh vacuum four-probe scanning tunneling microscope. Anisotropic conductivity is observed that is caused by the interaction between the graphene and the underlying substrate. These results can be explained by a model where charge buildup at the step edges leads to local scattering of charge carriers. This highlights the importance of considering substrate effects in proposed devices that utilize nanoscale patterning of graphene on electrically isolated substrates.
authors.affiliation: U.S. Naval Research Laboratory, Washington, D.C. 20375, USA.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Yakes
authors.forename: Daniel
authors.initials: D
authors.lastname: Gunlycke
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Tedesco
authors.forename: Paul M
authors.initials: PM
authors.lastname: Campbell
authors.forename: Rachael L
authors.initials: RL
authors.lastname: Myers-Ward
authors.forename: Charles R
authors.initials: CR
authors.lastname: Eddy
authors.forename: D Kurt
authors.initials: DK
authors.lastname: Gaskill
authors.forename: Paul E
authors.initials: PE
authors.lastname: Sheehan
authors.forename: Arnaldo R
authors.initials: AR
authors.lastname: Laracuente
mesh_terms: D017554:Carbon Compounds, Inorganic / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D004553:Electric Conductivity; D006108:Graphite / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D020527:Microscopy, Scanning Probe / Q000379:methods*; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D017655:Silicon Compounds / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D017554:Carbon Compounds, Inorganic; D046911:Macromolecular Substances; D017655:Silicon Compounds; D006108:Graphite; C022088:silicon carbide