Irregularity of film resistivity in a contact interface and contact conductance

The contact conductances are computed and the global behavior of contact phenomena is studied, using the same method and model as in previous papers, for the case where the film resistivity of a contact interface irregularly fluctuates against the position of the interface. The model of contact consists of two unit conducting cubes and a contact interface between the cubes. The interface is divided into a great number of square spots, and the resistivity of each spot is randomly determined, but the statistical distribution of the resistivities is assumed to be the normal (Gauss) distribution or error function. It is clarified that the contact conductance does not become low when the standard deviation of the normal distribution is large (i.e. the positional variation of the resistivity is large and spots with high and low resistivity coexist in the same interface) even if the average value of resistivity greatly rises.>