Model for the decrease in HBT collector current under DC stress based on recombination enhanced defect reactions

Based on simplifying assumptions a model is developed to describe decreasin g HBT collector current under DC bias stress. The underlying processes are recombination enhanced defect reactions (REDR), namely defect generation an d defect annealing. The simplification of the derived equation under partic ular boundary conditions leads to a form of the Eyring relationship general ly employed to describe the decrease in collector current under DC bias str ess. Additionally, pulsed tests with an emitter current density of J(E) = 2 00 kA/cm(2) have been performed The comparison between measured data from t hese tests and their fit proofs the applicability of the derived equation. Of course this can not be an evidence for the real running physical process es. (C) 2000 Elsevier Science Ltd. All rights reserved.