Low noise HEMTs with multi-feed gate configurations

A novel multifeed gate configuration using air-bridge metallization is demonstrated for low-noise high electron mobility transistors (HEMTs). The configuration is designed according to the detailed analysis of parasitic gate capacitances. Very low noise figures of 0.55 and 1.6 dB have been achieved at 12 and 40 GHz for 0.25 mu m gate AlGaAs/InGaAs pseudomorphic HEMT respectively. A noise figure of 4.1 dB and a gain of 12.2 dB at 40 GHz were obtained for two-stage HEMT monolithic microwave integrated circuits.<
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