InP/InGaAs double heterojunction bipolar transistor (DHBT) with an emitter tunneling barrier and composite collector structure

The DC performances of a novel InP/InGaAs double-heterojunction bipolar transistor (DHBT) with the undoped tunneling barrier and composite collector structure are studied and demonstrated. Due to the mass filtering effect for holes, a thin InP tunneling barrier can be used to replace the wide-gap emitter. Experimentally, an extremely small offset voltage of 25 mV and breakdown voltage BV/sub CEO/ of 9.2 V are obtained. Furthermore, the abrupt junction and /spl delta/-doping structure can eliminate the carrier blocking effect effectively when electrons are transported across the base-collector heterojunction. Meanwhile, the DC current gain is almost independent of the perimeter-to-area ratio of the emitter due to the low surface recombination.