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A three-stage monolithic amplifier has been developed which exhibits a measured small-signal gain of 30 dB at 140 GHz. The circuit employs 0.1-/spl mu/m AlInAs-GaInAs-InP HEMT devices with 150 /spl mu/m gate peripheries, and occupies a total area of 2 mm/sup 2/. Measured gain exceeds 10 dB from 129-157 GHz and 5 dB up to 184 GHz. This is the highest gain(More)
In this paper we report on the development of W-band MMIC power amplifiers using 0.1 /spl mu/m AlInAs-GaInAs-InP HEMT technology and finite-ground coplanar waveguide (FGCPW) designs. Two single-stage single-ended W-band MMICs using 150 /spl mu/m and 250 /spl mu/m wide HEMTs were designed, fabricated and tested. The results show that the small signal(More)
In this work, we investigated the use of 10-layer InAs quantum dot (QD) as active region of an electroabsorption modulator (EAM). The QD-EAM is a p-i-n ridge waveguide structure with intrinsic layer thickness of 0.4 mum, width of 10 mum, and length of 1.0 mm. Photocurrent measurement reveals a Stark shift of ~5 meV (~7 nm) at reverse bias of 3 V (75 kV/cm)(More)
Ten-layer InAs/In 0.15 Ga 0.85 As quantum dot (QD) laser structures have been grown using molecular beam epitaxy (MBE) on GaAs (001) substrate. Using the pulsed anodic oxidation technique, narrow (2 lm) ridge waveguide (RWG) InAs QD lasers have been fabricated. Under continuous wave operation, the InAs QD laser (2 · 2,000 lm 2) delivered total output power(More)
Low energy Ar + ion sputtering, typically below 1,200 eV, of GaAs at normal beam incident angle is investigated. Surface morphology development with respect to varying energy is analyzed and discussed. Dot-like patterns in the nanometer scale are obtained above 600 eV. As the energy approaches upper eV range regular dots have evolved. The energy dependent(More)
In this paper, a high-performance four-stage MMIC low noise amplifier based on InP HEMT and grounded CPW (GCPW) technology is presented. The LNA exhibits a measured gain of 20/spl plusmn/3 dB from 85 to 119 GHz, a 33% bandwidth. The noise figure is 3.7 dB at 93 GHz. The measured amplifier P/sub 1 dB/ is 10 mW at 98 GHz.
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