The impact on current density and constriction resistance from bridge structures in real contacts

The present work addresses the effects that occur from adjacent bridge structures that are believed to exist in real contacts. While in the present work these structures are idealized using hyperbolic surfaces, it is believed they provide reasonable estimates of what can happen in real situations. Using this approach, it is shown that the current density distribution across the contact remains finite as compared to the idealized co-planar case. Moreover, it is shown that the voltage drop across the contact region is slightly higher with the presence of a bridge; thus, one would expect higher contact resistances in real contacts. The extent to which this occurs depends on the details of real contact bridge structures. In addition, it was shown that estimates of equipotential and flow lines can be constructed using geometrical considerations. In this case it is believed this would help in estimating contact resistance.