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

摘要

High-performance metamorphic $hbox{Al}_{0.49}hbox{In}_{0.51}hbox{As-/} breakhbox{Ga}_{0.47-}hbox{In}_{0.53}hbox{As}$ 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 $hbox{4.5} times hbox{10}^{12} hbox{cm}^{-2}$ with a mobility of over 7500 $hbox{cm}^{2}/hbox{V}cdot hbox{s}$. Maximum transconductance of mHEMTs with a 100-nm gate length was $sim$ 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 $(f_{T})$ and the maximum oscillation frequency $(f_{rm max})$ were 210 and 146 GHz, respectively. To our best knowledge, these results are the best reported for MOCVD-grown mHEMTs on Si.