W-band InGaAs HEMT low noise amplifiers

The authors report 0.15- mu m gate length GaAs-based and InP-based InGaAs channel high-electron-mobility transistors (HEMTs) that have exhibited state-of-the-art noise and gain performance well up to 100 GHz. 94-GHz noise figures of 2.4 and 1.4 dB with gains of 5.4 and 6.5 dB have been measured from GaAs- and InP-based HEMTs, respectively. High-performance W-band multistage amplifiers have been built using these devices. A two-stage GaAs-based amplifier exhibits a noise figure of 4.2 dB with a gain of 9.7 dB at 93 GHz, and a three-stage amplifier yields a 4.5-dB noise figure with 14.8-dB gain at 94 GHz. The best two-stage amplifier built with InP-based HEMTs exhibits a minimum noise figure of 3.2 dB with a gain of 11.5+or-0.4 dB from 88 to 96 GHz. A noise figure as low as 3.3 dB with gain of 17.3+or-0.5 dB from 88 to 96 GHz has also been demonstrated from a three-stage amplifier. The characteristics and performance of both devices are presented.<>