Barrier effects in SiGe HBT: modeling of high-injection base current increase

Abstract

The HBT's parasitic energy band barrier formation, located at the hetero-interface, was investigated. Physical simulations show that additional base current increase in the high-injection regime is associated with the parasitic barrier formation. The charge calculation related to the parasitic barrier allows us to derive a model for the base current increase which is implemented into an electrical scalable compact model and applied on measurements.