Comparative analysis of compact noise model formulations for SiGe-HBTs

Abstract

In this paper a comparative analysis of compact noise model formulations for intrinsic bipolar transistors is presented. The analysis includes the approximated transport noise model feasible for compact model implementations and a correlated noise model derived from the non quasi-static theory of bipolar transistors. The models are first compared at the intrinsic device level, taking as reference analytical curves derived from the Van der Ziel/Van Vliet noise theory. Differences and limitations of the noise models are discussed. Finally, depletion capacitances and parasitic resistances are added to the intrinsic noise models to enable experimental assessment of their significance with respect to measured data on an industrial device.