Title :
Quarter-micrometer low-noise pseudomorphic GaAs HEMTs with extremely low dependence of the noise figure on drain-source current
Author_Institution :
Daimler-Benz AG Res. Center, Ulm, Germany
Abstract :
Quarter-micrometer pseudomorphic (PM) AlGaAs-InGaAs-GaAs HEMTs with an In mole fraction of 21% have been successfully developed, fabricated, and characterized. The devices are realized in a commercial technology by using a multiple-gate-finger layout with air bridges for the interconnection of the source pads and a Si/sub 3/N/sub 4/ passivation. PM HEMTs with a gate width of 6*20 mu m exhibit state-of-the-art noise figures of 0.65 and 0.82 dB with an associated gain of 14.5 and 11.5 dB at 12 and 18 GHz, respectively. The noise figure shows the lowest dependence on the drain-source current yet reported with Delta F/sub max/<0.12 dB for a wide biasing range from 25% I/sub dss/ up to 150% I/sub dss/ at 12 GHz when I/sub dss/=170-250 mA/mm.<>
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; high electron mobility transistors; indium compounds; passivation; semiconductor device noise; silicon compounds; solid-state microwave devices; 0.25 micron; 0.65 dB; 0.82 dB; 11.5 dB; 12 GHz; 14.5 dB; 18 GHz; 20 micron; AlGaAs-InGaAs-GaAs; Si/sub 3/N/sub 4/ passivation; air bridges; drain-source current; gain; gate width; low dependence on current; multiple-gate-finger layout; noise figure; semiconductors; Bridges; Fabrication; Frequency; Gallium arsenide; HEMTs; Integrated circuit technology; Intrusion detection; MODFETs; Molecular beam epitaxial growth; Noise figure;
Journal_Title :
Electron Device Letters, IEEE
