Electrical characterization of epitaxial graphene field-effect transistors with high-κ Al₂O₃ gate dielectric fabricated on SiC substrates

Top-gates 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 dielectrica 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 growt of Al₂O₃ over the graphene. Electrical measurements yielded a rise in the maximum transconductance and a significant shifting of the Dirac point as the operating temperature of the transistor was increased.