MICROWAVE CHARACTERISTICS OF A CARBON-DOPED BASE INP INGAAS HETEROJUNCTION BIPOLAR-TRANSISTOR GROWN BY CHEMICAL BEAM EPITAXY/

The first high-speed operation of an InP/In0.53Ga0.47As heterojunction bipolar transistor (HBT) using a highly carbon-doped base is reported . A base carrier concentration of 7 x 10(19)/cm3 was achieved by chemi cal beam epitaxy (CBE). To the authors' knowledge, this is the highest doping level reported using carbon. The f(T) and f(max) of the HBT wi th two 1.5 x 15 mum2 emitter fingers were 115GHz and 51 GHz, respectiv ely, at I(c) = 60mA and V(CE) = 2.0V. These results indicate the signi ficant potential of highly carbon-doped-base InP/InGaAs HBTs for high- speed applications.