A 180-GHz MMIC sub-harmonic mixer based on InGaAs/InAlAs/InP HEMT diodes

A monolithic sub-harmonic mixer is designed for RF frequencies at 180 GHz. It is fabricated on a 2-mil thick InP substrate using 0.08-/spl mu/m pseudomorphic InAlAs/InGaAs HEMT process. In-fixture measurements from 175 to 182 GHz with a sub-harmonic LO drive of 13 dBm at 96 GHz show a conversion loss of 15 dB. This is the first demonstration of a monolithic HEMT diode sub-harmonic mixer working in the RF band of 180 GHz.