Model for InGaP/GaAs/InGaP double heterojunction bipolar transistor

The current–voltage characteristics of an InGaP/GaAs/InGaP double heterojunction bipolar transistor (DHBT) are modeled where the tunneling effect at the base–collector (B–C) junction and base–emitter (B–E) junction is taken into account. Therefore, this model can be applied to both conventional DHBT and composite collector heterojunction bipolar transistor. The role of the n−GaAs layer and n+InGaP layer are discussed and the effects of variation in the doping level and thickness of these layers are considered in the model. Good agreement between our predictions of the model and reported experimental results is achieved.