The role of high-doped source and drain on device performance in nano-scale Si-MOSFETs

Monte Carlo simulations coupled self-consistently with the 3D Poisson equation under the Double-Gate MOSFET structures are carried out to investigate quantitatively the dynamical potential fluctuations of the Coulomb interaction. It is shown that the potential fluctuations lead to the band-tail in the space-averaged density of states and it becomes position-dependent even inside the source where quasi-equilibrium is usually presumed. This implies that electrons in the source near the channel could be under highly off-equilibrium.