Greens function approach to transport through a gate-all-around Si nanowire under impurity scattering

We investigate transport properties of gate-all-around Si nanowires using non-equilibrium Greens function technique. By taking into account of the ionized impurity scattering we calculate Greens functions self-consistently and examine the effects of ionized impurity scattering on electron densities and currents. For nano-scale Si wires, it is found that, due to the impurity scattering, the local density of state profiles loose its interference oscillations as well as is broaden and shifted. In addition, the impurity scattering gives rise to a different transconductance as functions of temperature and impurity scattering strength when compared with the transconductance without impurity scattering.