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 10⁶ and on-state current density as high as ∼2000  μA/μm. We estimated carrier mobility ∼200  cm²/V s and scattering mean free path ∼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≤∼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.