Room-temperature all-semiconducting sub-10-nm graphene nanoribbon field-effect transistors

Sub-10 nm wide graphene nanoribbon field-effect transistors (GNRFETs) are studied systematically. All sub-10 nm GNRs afforded semiconducting FETs without exception, with I-on/I-off ratio up to 10(6) and on-state current density as high as similar to 2000 mu A/mu m. We estimated carrier mobility similar to 200 cm(2)/V s and scattering mean free path similar to 10 nm in sub-10 nm GNRs. Scattering mechanisms by edges, acoustic phonon, and defects are discussed. The sub-10 nm GNRFETs are comparable to small diameter (d <=similar to 1.2 nm) carbon nanotube FETs with Pd contacts in on-state current density and I-on/I-off ratio, but have the advantage of producing all-semiconducting devices.