Ultrahigh performance staggered lineup ("Type II") InP/GaAsSb/InP NpN DHBTs

Using a conventional emitter-up triple-mesa process, we have fabricated C-doped InP/GaAsSb/InP double heterojunction bipolar transistors (DHBTs) exhibiting both f/sub T/ and f/sub MAX/=300 GHz while maintaining a breakdown voltage BV/sub CEO/=6 V. Our devices feature stable and well-behaved common-emitter DC and RF characteristics up to J/sub C/=500 kA/cm/sup 2/ without any passivation nor heatsinking. InP/GaAsSb/InP abrupt junction DHBTs couple unprecedented performance to apparent manufacturability advantages which should enable applications well beyond 40 Gb/s and challenge InP HEMTs in the 80-100 Gb/s arena.