Role of phonon scattering in graphene nanoribbon transistors: Nonequilibrium Green's function method with real space approach

We report self-consistent NEGF transport simulation results in graphene nanoribbon transistors with phonon scattering in real space. Unlike mode space approach, this technique can account for interband scattering in addition to intraband scattering. We show a seamless transition from ballistic to dissipative transport by varying channel length over a wide range. We find acoustic phonon (AP) scattering to be the dominant scattering mechanism within the relevant range of voltage bias. Optical phonon scattering is significant only when a large gate voltage is applied. In a longer channel device, the contribution of AP scattering to the dc becomes more significant. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3589365]