W-band MMICs with 0.15 mu-m metamorphic InAlAs/InGaAs HEMTs on GaAs substrate - performance, thermal- stability and reliability

We report on fabrication, performance and reliability of 0.15 mum gate-length passivated InAlAs/InGaAs metamorphic HEMT MMICs on GaAs substrate. The HEMTs show an measured maximum stable gain of 13.5 dB at 94 GHz, giving an extrapolated f(max) of 450 GHz. Two stage W-band high gain amplifiers with 18 dB gain and 20 GHz bandwidth are demonstrated. The robustness of our MHEMT MMIC technology is demonstrated by high temperature stress under N-2 and H-2 ambient. Furthermore, we have found that metamorphic and lattice matched HEMTs and LMHEMT have comparable reliability.