Predictive TCAD modeling of the scaling-induced, reverse-biased, emitter-base tunneling current in SiGe HBTs

We investigate, for the first time, predictive TCAD modeling of scaling-induced, reverse-biased emitter-base junction tunneling current in state-of-the-art SiGe HBTs. Different operative tunneling mechanisms are identified, including important factors that determine the accuracy of the simulations. The models for different tunneling mechanisms are applied to multiple generations of SiGe HBTs to examine their validity. Implications of these results and their use in TCAD-based device optimization are discussed. Finally, this study highlights the nature of the emitter-base junction degradation that results from an accelerated stress in the tunneling regime for different generations of SiGe HBTs.