ON THE USE OF S-PARAMETER MEASUREMENTS TO MODEL HBT INTRINSIC ELEMENTS FOR LARGE-SIGNAL ANALYSIS PURPOSES

S-parameter measurements at 50 bias points covering the saturation and the active operating mode regions are used to model the bias dependen ce of the equivalent circuit elements representing the intrinsic part of a 3 x 5 mum2 HBT It is shown that most of the intrinsic elements de pend significantly on the biasing base current. Among these elements, some are also relatively dependent on the collector-emitter voltage. T he intrinsic element bias-dependent equations are determined in such a manner that they model the device in both active and saturation regio ns. These element models are important in the development of a large-s ignal HBT model useful in nonlinear simulations. (C) 1993 John Wiley & Sons, Inc.