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We report on the growth of In0.30Ga0.70As channel high electron mobility transistor (HEMT) epi-layers on a 200-mm Si substrate by metal-organic-chemical-vapor-deposition. The HEMT layers were grown on the Si substrate by using a ~3- \mu \textm thick epitaxial buffer composing of a Ge layer, a GaAs layer, and a compositionally graded and strain relaxed InAlAs layer. The optimized epitaxy has a threading dislocation density of less than 2 \times 10^7 cm−2 and a root mean square surface roughness of ~6.7 nm. The device active layers include a \delta -doped InAlAs bottom barrier, a ~15-nm thick InGaAs channel, a ~8-nm InGaP top barrier layer and a heavily doped InGaAs contact layer. MOSHEMTs with channel length down to 130 nm were fabricated. The devices achieve a peak transconductance of \sim 450 ~\mu \textS/ \mu \textm at V D of 0.5 V. The peak effective mobility ( \mu \text {eff} ) in a device with a channel length of 20 \mu \textm device channel was ~3700 cm2/ \textV \cdot \texts . [ABSTRACT FROM AUTHOR]

Integration of InxGa1–xAs n-MOSFETs and SiyGe1–y p-MOSFETs could be a key to realize future low-power and high-speed logic circuits. In this paper, monolithic integration of InAs n-MOSFETs and Ge p-MOSFETs on a Si substrate is reported. To address the challenge of integrating materials with large lattice mismatch (InAs and Ge on Si substrate), a sub-120-nm GaSb-on-GaAs buffer on a germanium-on-insulator (GeOI) starting substrate is employed. The strain resulting from the 7.78% lattice mismatch between the GaSb and GaAs layers is mainly relaxed via interfacial misfits at the GaSb/GaAs interface, enabling significant reduction in the buffer thickness. For device fabrication, a self-aligned gate last process flow with Si-CMOS-compatible modules is used. To realize raised source-drain device architecture, a combination of dry and digital etch processes is developed to etch InAs and Ge cap layers. Devices with channel thicknesses less than 5 nm and channel lengths less than 200 nm are realized for both n- and p-MOSFETs, with promising electrical characteristics. [ABSTRACT FROM PUBLISHER]