A W-band monolithic mixer is designed and fabricated using InAlAs/InGaAs HEMT technology. The advantages of this material system compared with AlGaAs/GaAs are: i) larger conduction band discontinuity (0.5 eV versus 0.24 eV for AlGaAs/GaAs) and therefore better carrier confinement, ii) higher low-field mobility, and iii) higher peak velocity. The combination of these features results in a better performance and operation capability in the submillimeter wave range. The design procedure and the circuit performance are described. A very low LO (local oscillator) power requirement is demonstrated with 13.5-dB conversion loss and only -6-dBm LO drive at 95 GHz.
