Scaling laws for electrical contact resistance with dissimilar materials

Abstract

This paper attempts to quantify the effects of contaminants on electrical contact resistance. Based on an idealized model, simple and explicit scaling laws for the electrical contact resistance with dissimilar materials are constructed. The model assumes arbitrary resistivity ratios and aspect ratios in the current channels and their contact region, for both Cartesian and cylindrical geometries. The scaling laws have been favorably tested in several limits, and in sample calculations using a numerical simulation code. From the scaling laws and a survey of the huge parameter space, some general conclusions are drawn on the parametric dependence of the contact resistance on the geometry and on the electrical resistivity in different regions.