Enhanced Carbon Confinement of Ultranarrow Boron Profiles in SiGeC HBTs

This paper reports on observations of enhanced carbon confinement of ultranarrow boron profiles in silicon-germanium-carbon heterojunction bipolar transistors (SiGeC HBTs). Electrical measurements of HBT devices with base regions formed during a low-pressure chemical-vapor deposition, with this method shows that a current gain (beta) is increased, base sheet resistance (R
_bs
) is reduced, and the maximum oscillation frequency (f
_max
) is improved