Local band-to-band-tunneling model for tcad simulation

Abstract

An improved local modeling function for estimating band-to-band tunneling currents Rin nanodevices and other low-voltage circuit elements during TCAD simulation, the model being represented by the equation: where terms B, F, Fand σ correspond to conventional terms used in Hurkx-based equations, and the term g is an exponential factor determined by the equation: where the term Fis the built-in electric field at a selected cell/point determined by the equation: where {tilde over (F)}is the built-in electric field at zero bias, q is fundamental electronic charge, C is a fitting parameter, Eis bandgap, Nis doping concentration, and E is dielectric constant. At low applied fields (F˜F) the factor g biases the improved model toward the zero-field/zero-current origin in a way that closely matches non-local model results. At higher applied fields the factor g has less influence and the model is controlled by the conventional terms.