J. Abrahams

High-performance InAlAs/InGaAs HEMTs and MESFETs

The fabrication and microwave performance of heterostructure InAlAs/InGaAs HEMTs (high-electron-mobility transistors) and MESFETs are described. Maximum stable gains of 14.3 dB for a HEMT and 12 dB for a MESFET at 26.5 GHz have been achieved. These are believed to be record gains for FETs having gates as long as 0.7 mu m.<<ETX>>

Monolithic integration of InGaAs/InAlAs MODFETs and RTDs on InP-bonded-to Si substrate

The authors report the monolithic integration of InGaAs/InAlAs MODFETs and RTDs MBE grown using selective epitaxy on InP which has been bonded to a silicon substrate. The study demonstrates the feasibility of monolithically integrating III-V devices having different heterostructures with silicon devices.<<ETX>>

Growth and fabrication of InGaAs/InAlAs HEMTs on bonded-and-etch-back InP-on-Si

InGaAs/InAlAs HEMTs fabricated on bonded-and-etched-back InP-on-Si substrates are reported. The process involves depositing SiO/sub 2/ on both the Si and InP substrates. The wafers are then contacted and bonded in a furnace at low temperature. Defects in the bond can be minimized by bonding in a particle-free environment. After bonding to a Si substrate, the InP wafer is thinned to <10 mu m and a strain-relief grid is etched through the InP to the SiO/sub 2/ layer. For fabrication of the HEMT, a standard processing sequence of mesa isolation, ohmic-contacts formation, gate-metal deposition and overlay was used. A maximum transconductance of 180 mS/mm was measured for a 1.2- mu m-gate-length device.<<ETX>>

High-current, planar-doped pseudomorphic hemts Ga0.4In0.6As/Al0.48In0.52As HEMTs

The letter reports the first successful growth and fabrication of high-performance, planar-doped pseudomorphic GaInAs/AlInAs HEMTs. Hall mobilities as high as 11900cm2/Vs (300 K) with sheet-electron concentrations of 2.4 × 1012cm−2 were measured for the heterostructures. A drain-saturation current of 1 A/mm, a transconductance of 420mS/mm, and an extrapolated f1 of 64 GHz were achieved in a 0.5 μm gate-length HEMT.

DC and RF performance of MBE grown InAlAs/InP MODFETs

Summary form only given. The authors report the state-of-the-art RF performance of InAlAs/InP MODFETs, grown for the first time via MBE (molecular beam epitaxy). The S-parameters of the FETs were measured from 0.5 to 26.5 GHz for various bias voltages (both V/sub gs/ and V/sub ds/). Maximum stable gains (MSGs) of 13 and 11.5 dB at 18 and 26.5 GHz, respectively, were measured for a source-drain voltage of 7.0 V. Extrapolating MSG at 6 dB/octave, a maximum oscillation frequency of about 75 GHz is predicted.<<ETX>>

Increased breakdown voltages in In/sub 1-x-y/Ga/sub x/Al/sub y/As/InAlAs FETs

The authors report the performance of In/sub 1-x-y/Ga/sub x/Al/sub y/As FETs lattice-matched to InP. An improvement in the drain-source breakdown voltage was achieved by adding Al in the channel of InGaAs/InAlAs FETs. The microwave gains are comparable to those of the InGaAs/InAlAs FETs. The DC and RF characteristics are discussed.<<ETX>>

A novel InAlAs/InP/InAlAs pnp double heterojunction bipolar transistor grown by MBE

The authors report the growth and fabrication of a double-heterojunction bipolar transistor (DHBT) using the InP/InAlAs material system. The measured Gummel plot exhibits a collector current ideality factor of 1.25 and a base current ideality factor of 1.5. A collector-emitter breakdown voltage of 6.5 V was measured. From the measured S-parameters, the extrapolated current-gain-cut-off frequency for a 5- mu m*5- mu m size device was 6.5 GHz. The results obtained indicate that the InP/InAlAs heterostructure grown by molecular beam epitaxy is suitable for p-n-p HBTs (heterojunction bipolar transistors).<<ETX>>

DC and microwave performance of Indium-based heterojunction field-effect transistor fabricated on Si-InP

This paper reports the fabrication and microwave performance of MODFETs (InGaAs/InAlAs) and two types of heterojunction MESFETs (undoped InAlAs/n-InGaAs or n-InP). Gains of 12.5 dB at 26 GHz were measured for 1.3 µm gate length MODFETs, which extrapolates ta a fmaxof over 100 GHz. Maximum available gains of about 15.5 dB for the InGaAs and 11 dB for InP channel MESFETs were measured at 10 GHz. These devices outperformed similar devices previously reported in the literature.