Tunneling is a sensitive function of the electric field, whereas the electric field in MOSFETs depends on several parameters such as the oxide thickness, the dopant distribution, the interface fixed charge and trap density, the geometry of the gate corner and the terminal biases. As a consequence, tunneling in MOSFETs can only be properly modeled by a numerical approach. Several papers consider the numerical modeling of band-to-band tunneling in MOSFETs [485][354][353][347][326][260][143].
A two-dimensional numerical model of band-to-band tunneling in MOS transistors has been developed [170]. After describing the approach in the first part of this section we shall investigate the potential and field distribution in the critical gate/drain overlap region in the second part of the section.