50 nm MHEMT Technology for G- and H-Band MMICs

A metamorphic HEMT (MHEMT) MMIC technology including circuit applications is presented. The MHEMT layers are MBE grown on 4-inch GaAs wafers. The technology is based on a 50 nm gate length MHEMT and includes a 50 μm substrate backside process with dry etched through-substrate vias. For the electron confinement an ln 0.8 Ga 0.2 As/ln 0.53 Ga 0.47 As composite channel was used. The devices are passivated with BCB and SiN to achieve a median time-to-failure of 2.7×10 6 h in air. Cut-off frequencies f t and f max of 375 GHz were extrapolated for a 2 × 15 μm gate width device. Low-noise amplifiers with more than 15 dB gain in the frequency range from 192 GHz to 235 GHz were realized.