Analysis of gate tunneling current in MOS structures using quantum mechanical simulation

We report studies of quantum transport in n(+)Si-SiO2-P Si Metal-Oxide-Semiconductor (MOS) structures based upon a non-equilibrium tight-binding Green's function method. As a result, the quasi-bound states at the SiO2-P Si interface are found to be lower than those calculated by the conventional Shrodinger-Poisson analysis, since the wavefunctions in this region are coupled with the Bloch functions in the electrodes. It is also found that the leakage current through the oxide consists of not only the intraband tunneling but also the interband tunneling current.