Fully passivated W-band InAlAs/InGaAs/InP monolithic low noise amplifiers

The development of W-band monolithic low noise amplifiers (LNAs) using a fully passivated 0.1 mu m pseudomorphic InAlAs/InGaAs/InP low noise HEMT technology is presented. Both wafer passivation and stabilisation bakes have been introduced, for the first time, to the InP HEMT MMIC process to make it more suitable for production. A three-stage single-ended 94 GHz monolithic LNA shows a measured noise figure of 3.3 dB and 20 dB associated gain. A measured noise figure of 2.3 dB is achieved for a single-stage MMIC LNA at 94 GHz. These results represent state-of-the-art performance of HEMT MMIC LNAs at this frequency. The effects due to SiN passivation for both HEMT device and circuit performance are also addressed.