A multilayer exponential model for spreading resistance calculations

Abstract A new multilayer approach to spreading-resistance correction-factor calculations is proposed, based on the approximation of the graded resistivity profile by a series of exponential functions. The existence of a recurrence formula for the integration factor in the correction factor integral makes the proposed model a practical alternative to Schumann and Gardner's staircase model. Although a factor of 3 slower in terms of computation time, the exponential model yields results much closer to the true profile than the staircase model, particularly in cases where the profile has very steep gradient but where the available measurement data points are sparse.