160-190-GHz monolithic low-noise amplifiers

This letter presents the results of two 160-190-GHz monolithic low-noise am plifiers (LNA's) fabricated with 0.07-mu m pseudomorphic (PM) InAlAs/InGaAs /InP HEMT technology using a reactive ion etch (RIE) via hole process, A pe ak small signal gain of 9 dB was measured at 188 GHz for the first LNA with a 3-dB bandwidth from 164 to 192 GHz while the second LNA has achieved ove r 6-dB gain from 132 to 180 GHz. The same design (second LNA) was also fabr icated with a 0.08-mu m gate and a wet etch process, showing a small-signal gain of 6 dB with 6-dB noise figure. All the measurement results were obta ined via on-wafer probing. The LNA noise measurement at 170 GHz is also the first attempt at this frequency.