Ultra-high speed composition graded InGaAsSb/GaAsSb DHBTs with f/sub T/ = 500 GHz grown by gas-source molecular beam epitaxy

Graded InGaAsSb:C base double heterojunction bipolar transistors (DHBT) were grown on InP to enhance the electron transit time through the base region. A record high unity current gain frequency f
_T
of 500 GHz is achieved in the DHBT with a 250 Aring thick InGaAsSb:C linear graded base