Abstract
High quality GaAsSbInP double heterojunction bipolar transistor (DHBT) structures were grown using gas-source molecular beam epitaxy. The substrate temperature and V/III flux ratio were optimized to grow single phase GaAsSb base layers lattice matched to InP. The dc gain as high as 40 was obtained in 60×60 μ m2 GaAsSbInP DHBTs with a 500 Å carbon doped (7× 1019 cm-3) GaAsSb base layer. High performance DHBT with a 250 Å base layer shows a current gain cutoff frequency fT of 346 GHz and maximum oscillation frequency fmax of 145 GHz. © 2006 American Vacuum Society.