Conductance anisotropy in epitaxial graphene sheets generated by substrate interactions.
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.
Yakes
Michael K
MK
U.S. Naval Research Laboratory, Washington, D.C. 20375, USA.
Gunlycke
Daniel
D
Tedesco
Joseph L
JL
Campbell
Paul M
PM
Myers-Ward
Rachael L
RL
Eddy
Charles R
CR
Gaskill
D Kurt
DK
Sheehan
Paul E
PE
Laracuente
Arnaldo R
AR
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
D017554:Carbon Compounds, Inorganic; D046911:Macromolecular Substances; D017655:Silicon Compounds; D006108:Graphite; C022088:silicon carbide