Modelling the DC performance of GAAS Homojunction bipolar transistors

Two models, one analytical and one numerical, have been developed to predict the dc performance of GaAs homojunction bipolar transistors. In each case the minority carrier properties of lifetime and mobility have been described by polynomial fits to recent data. Bandgap narrowing in the emitter and base regions has also been taken into account. The analytical model assumes uniform doping in the three regions of the transistor and is thus appropriate to predicting the performance of devices fabricated using epitaxial technologies. This model is also useful for carrying out sensitivity analyses. The importance of parameters such as regional widths and doping densities, minority carrier lifetimes and surface recombination velocity is examined here. The numerical model is useful for describing the performance of ion-implanted devices. Good agreement is obtained between results from the model and recent experimental data from prototype devices.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat