Novel InGaP/GaAsSb/GaAs DHBTs

A study of the InGaP/GaAsSb/GaAs double heterojunction bipolar transistor (DHBT) is presented. Novel device structure is designed. A fully strained pseudomorphic GaAsSb with 8.0% Sb composition is used as the base layer, while an InGaP layer as the emitter which both eliminates the misfit dislocations and increases the valence band discontinuity at the InGaP/GaAsSb interface. A current gain of 22.6 has been obtained from the InGaP/GaAsSb/GaAs DHBT. Typical turn-on voltage of the device is 0.973 V which is 0.116V lower than that of traditional InGaP/GaAs HBT. Moreover, the current transport mechanism of the InGaP/GaAsSb/GaAs DHBTs is investigated. These results show that GaAsSb is a promising base material for reducing the turn-on voltage of GaAs HBTs.