Extraction of the base and emitter resistances in bipolar transistors using an accurate base resistance model

A straightforward method for extracting the base and emitter resistances is presented. The method has the following properties: 1) only a standard forward Gummel measurement on one transistor is required; 2) current-crowding and conductivitymodulation in the base are accounted for through the use of an accurate base resistance model; and 3) the resistance parameters are extracted using a nonlinear optimization step. Furthermore, a technique for extraction of the high-injection parameters of a modified collector current model is also presented.