1-D BJT parameter extraction for Cuasi-3D simulation of four-layer devices

Cuasi-3D simulation methods allow extending 2D numerical simulations to the 3rd dimension, in ways that trade detail of information for computational efficiency. The Cuasi-3D simulation method of 4-layer power devices reported previously by the author requires Gummel-Poon BJT parameters, that should ideally be derived from 1D charge transport simulations. The desired one-dimensionality can only be approximated with standard 2D simulators such as Atlas, due mainly to current crowding. We report a novel one-dimensional parameter extraction method based on the charge transport equations, and implemented with the SGFW general purpose simulator. Unlike 2D simulations, where saturation currents are difficult to obtain because of the high mesh densities required at the junctions, very high 1D mesh densities can be simulated in less than 15 minutes in a Pentium IV computer. This parameter extraction method is faster and more precise than those based on 2D simulations.