Fabrication of 100-nm Metamorphic AlInAs/GaInAs HEMTs Grown on Si Substrates by MOCVD

High-performance metamorphic Al
_0.49
In
_0.51
As-/Ga
_0.47-
In
_0.53
As high-electron-mobility transistors (mHEMTs) grown on Si substrates by metal-organic chemical vapor deposition (MOCVD) using an effective multistage composite buffer scheme have been fabricated. Room-temperature Hall measurements show an average sheet carrier density of 4.5 × 10
¹²
cm
^-2
with a mobility of over 7500 cm
²
/V·s. Maximum transconductance of mHEMTs with a 100-nm gate length was ~ 770 mS/mm, which is nearly the same as that of mHEMTs with the same dimension grown on GaAs substrates by MOCVD. The unity current gain cutoff frequency (
fT
) and the maximum oscillation frequency (
f
_max
) were 210 and 146 GHz, respectively. To our best knowledge, these results are the best reported for MOCVD-grown mHEMTs on Si.