High-performance carbon-doped base GaAs/AlGaAs heterojunction bipolar transistor grown by MOCVD

High-performance HBTs with a carbon-doped base layer (p = 4 × 1019cm−3) are reported. The use of carbon as a p-type dopant allows the emitter-base pn junction to be accurately positioned relative to the heterojunction, and the MOCVD growth method ensures consistency and uniformity of the wafer epitaxial structure. Microwave HBTs with current gains hFE = 50 and fT and fmax values of 42GHz and 117GHz, respectively, are reported.