COMPARISON BETWEEN ANALYTICAL MODELS AND FINITE-DIFFERENCE SIMULATIONS IN TRANSMISSION-LINE TAP RESISTORS AND L-TYPE CROSS-KELVIN RESISTORS

Approximate analytical models of the transmission-line tap resistor and the cross-Kelvin resistor are compared with computer-simulated pseudo-three-dimensional resistor network models. The analytical formulas have been found to be in good agreement with the simulations over a useful range of parameters and are conveniently applied to the extraction of the contact resistivity and the sheet resistances of the semiconducting layer under and outside the contacts. The extracting procedure, easily implemented on a personal computer, is executed for the case of alloyed AuGeNi/GaAs contacts illustrating the importance of a distinction between layer sheet resistance under and outside the contacts and of a consideration of two-dimensional current flow in the semiconducting layer. © 1990 IEEE