Non-Stationary Transport HBT Modeling Under Non-Isothermal Conditions

Because of the interaction between thermal and hot carriers effects, neither isothermal nor conventional macro-thermal models are adequate for state-of-the-art power heterojunction bipolar transistors (HBTs); instead, a non-isothermal hot carrier transport model, such as the thermal-fully hydrodynamic model, is required. We apply such a detailed thermal model to the simulation of an AlGaAs/GaAs HBT, comparing the results with those provided by simplified models, and highlighting how deeply both non-stationary transport and self-heating affect the predicted device performance.