Electrical Characterization of Epitaxial Graphene Field-Effect Transistors with High-k Al₂O₃ Gate Dielectric Fabricated on SiC Substrates

Abstract:

Top-gated field-effect transistors have been created from bilayer epitaxial graphene samples that were grown on SiC substrates by a vacuum sublimation approach. A high-quality dielectric layer of Al₂O₃ was grown by atomic layer deposition to function as the gate oxide, with an e-beam evaporated seed layer utilized to promote uniform growth of Al₂O₃ over the graphene. Electrical characterization has been performed on these devices, and temperature-dependent measurements yielded a rise in the maximum transconductance and a significant shifting of the Dirac point as the operating temperature of the transistors was increased.

• Periodical: Materials Science Forum (Volumes 821-823)
• Pages: 937-940
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.821-823.937
• Online since: June 2015
• Authors: Toby Hopf, Konstantin Vassilevski*, Enrique Escobedo-Cousin, Peter King, Nicholas G. Wright, Anthony O'Neill, Alton B. Horsfall, Jonathan Goss, George Wells, Michael Hunt
• Keywords: AFM, ALD, Epitaxial Graphene, Graphene Field-Effect Transistors, Raman Spectroscopy, STM

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