High-Performance
Metamorphic InP/GaAsSb/InP “Type-II” DHBTs
Grown on
GaAs Substrates (Student Paper)
1)Y.
Zeng, 1)H.G. Liu, 1)N.G. Tao, and 1)C.R. Bolognesi,
1)Compound
Semiconductor Device Laboratory (CSDL),
2)Dept. of Electrical & Electronic Engineering,
HKUST
We report the fabrication of
high-performance metamorphic (MM) InP/GaAsSb/InP DHBTs grown on GaAs substrates
which show performances comparable or, in certain respects, superior to similar
structures grown on InP substrates. The
emitter base junction non-ideality factor is found to be significantly higher
in the MM devices when compared to the lattice-matched layers: this is believed
related to a significantly rougher emitter base junction compared to layers
grown lattice-matched on InP. Current
gain cutoff frequencies fT
as high as 110 GHz have been achieved with a 30 nm base and a 200 nm collector.