Consistency of boundary conditions in nonequilibrium Green’s function simulations

Abstract

The consistency of the boundary conditions imposed on the nonequilibrium Green’s function (NEGF) method is investigated by comparing the electron energy distribution at the drain end with the thermal equilibrium distribution. We show that the boundary condition is not consistently satisfied in the cases of ballistic transport and quasi-ballistic transport including scattering only in the channel region. It is pointed out that inclusion of scattering in the high-doped regions is inevitable to be consistent and crucial to obtain reliable transport characteristics.