▎ 摘　　要

Top-gated epitaxial-graphene nanoribbon (GNR) field-effect transistors on SiC wafers were fabricated and characterized at room temperature. The devices exhibited extremely high current densities (similar to 10 000 mA/mm) due to the combined advantages of the one-dimensionality of GNRs and the SiC substrate. These advantages included good heat dissipation as well as the high optical phonon energy of the GNRs and SiC substrate. An analytical model explains the measured family of I-D-V-DS curves with a pronounced 'kink' at a high electric field. The effective carrier mobility as a function of the channel length was extracted from both the I-D-V-DS modeling and the maximum transconductance from the I-D-V-GS curve. The effective mobility decreased for small channel lengths (<1 mu m), exhibiting ballistic or quasiballistic transport properties. (C) 2014 American Vacuum Society.