110-120-GHZ MONOLITHIC LOW-NOISE AMPLIFIERS

This paper presents the development of 110-120-GHz monolithic low-noise amplifiers (LNA's) using 0.1-mum pseudomorphic AlGaAs/InGaAs/GaAs low-noise HEMT technology. Two 2-stage LNA's have been designed, fabricated, and tested. The first amplifier demonstrates a gain of 12 dB at 112 to 115 GHz with a noise figure of 6.3 dB when biased for high gain, and a noise figure of 5.5 dB is achieved with an associated gain of 10 dB at 113 GHz when biased for low-noise figure. The other amplifier has a measured small-signal gain of 19.6 dB at 110 GHz with a noise figure of 3.9 dB. A noise figure of 3.4 dB with 15.6-dB associated gain was obtained at 113 GHz. The small-signal gain and noise figure performance for the second LNA are the best results ever achieved for a two-stage HEMT amplifier at this frequency band. To our knowledge, this is the first report of monolithic amplifiers operating above 100 GHz using three-terminal devices.