A quantum-mechanical charge transport simulation methodology

Abstract

A method was developed for finding charge and current distribution in nanoscale electronic devices such as MOS capacitors and resonant tunneling diodes. A system of differential equations, comprised of the Poisson and Schrödinger equations, was solved iteratively to find the electric field and charge distribution inside devices under simulation. The proposed solution method was based on the non-equilibrium Green’s function approach, but expands on that approach by using spatially varying quasi-Fermi levels to construct density operators. The proposed method was applied to several example device models. The simulation results are presented. Calculated charge distributions in FET transistors were found to have necessary features: for example, the results showed inversion layer formation. However, the calculated current-voltage curves differed significantly from published experimental results and other simulators. Other published methods for charge transport simulation are compared to the proposed method.