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This paper presents a new physical compact model for interface state creation due to hot-carrier degradation in advanced SiGe heterojunction bipolar transistors (HBTs). An analytical model for trap density is developed through an accurate solution of the rate equation describing generation and annihilation of interface traps. The analytical aging law has been derived and implemented in terms of base recombination current parameters in HiCuM compact model and its accuracy has been validated against results from long-term aging tests performed close to the safe-operating areas of various HBT technologies. The model implementation uses a single additional node, alike previous implementations, thereby preserving its simplicity, yet improving the accuracy and the physical basis of degradation. [ABSTRACT FROM AUTHOR]

We present and validate a physics-based model to describe the underlying mechanisms of hot-carrier degradation in bipolar transistors. Our analysis is based on a deterministic solution of the coupled system of Boltzmann transport equations for electrons and holes. The full-band transport model provides the energy distribution functions of the charge carriers interacting with the passivated Si–H bonds along the oxide interface. The simulation results assert the dominant role of hot holes along the emitter–base spacer oxide interface in the long-term degradation of an n-p-n SiGe heterojunction bipolar transistor under low and high-current conditions at the border of the safe-operating area. The interface trap density is calculated by incorporating an energy driven paradigm for the microscopicmechanisms of defect creation into a reaction-limitedmodelwith dispersive reaction rates. These interface traps increase the forward-mode base current via Shockley–Read–Hall recombination and degrade the overall device performance. The Gummel characteristics of a degraded device and time evolution of the excess base current for different stress conditions are verified versus the experimental data obtained for a state-of-the-art toward-terahertz SiGe HBT. [ABSTRACT FROM AUTHOR]