Room-Temperature All-Semiconducting Sub-10-nm Graphene Nanoribbon Field-Effect Transistors

Abstract

Sub-10 nm wide graphene nanoribbon field-effect transistors (GNRFETs) are studied systematically. All sub-10 nm GNRs afforded semiconducting FETs without exception, with ${I}_{\mathrm{on}}/{I}_{\mathrm{off}}$ ratio up to ${10}^{6}$ and on-state current density as high as $\ensuremath{\sim}2000\text{ }\text{ }\ensuremath{\mu}\mathrm{A}/\ensuremath{\mu}\mathrm{m}$. We estimated carrier mobility $\ensuremath{\sim}200\text{ }\text{ }{\mathrm{cm}}^{2}/\mathrm{V}\text{ }\mathrm{s}$ and scattering mean free path $\ensuremath{\sim}10\text{ }\text{ }\mathrm{nm}$ 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 ($d\ensuremath{\le}\ensuremath{\sim}1.2\text{ }\text{ }\mathrm{nm}$) carbon nanotube FETs with Pd contacts in on-state current density and ${I}_{\mathrm{on}}/{I}_{\mathrm{off}}$ ratio, but have the advantage of producing all-semiconducting devices.