Disorder-induced variability of transport properties of sub-5 nm-wide graphene nanoribbons

Transport properties of sub-5 nm-wide graphene nanoribbons (GNRs) are investigated by using atomistic non-equilibrium Green’s function (NEGF) simulations and semiclassical mobility simulations of large ensembles of randomly generated nanoribbons. Realistic GNRs with dimensions targeting the 12 nm CMOS node are investigated by accounting for edge defects, vacancies and potential fluctuations. Effects of disorder on transmission, transport gap, mean free path, density of states and acoustic phonon limited carrier mobility are explored for various disorder strengths and GNR widths in the 1–5 nm range. We report the high variability of GNR transport properties that could be a strong limiter for potential nanoelectronics applications of GNRs.

► We employ atomistic NEGF and semiclassical mobility simulations to investigate transport properties of sub-5 nm-wide GNRs.
► The transport gap and its variability increase with increasing disorder strength and downscaling of GNR width.
► The transport is scattering-dominated in the case of lattice defects and ballistic in GNRs with potential fluctuations.
► We propose an analytical model for the DOS of disordered GNRs based on the results of NEGF simulations.
► The acoustic-phonon-limited mobility in defected GNRs decreases and its variability increases as the width scales down.