A high-gain monolithic D-band InPHEMT amplifier

This paper describes a three-stage monolithic amplifier that exhibits a sma ll-signal gain of 30 dB at 140 GHz, The amplifier employs AlInAs/GaInAs/InP high electron mobility transistor devices with 0.1 x 150 mu m(2) gate peri phery, is implemented with coplanar waveguide circuitry fabricated on an In P substrate, and occupies a total area of 2 mm(2), Gain exceeding 10 dB was measured on-wafer from 129 to 157 GHz, This is the highest reported gain p er stage for a transistor amplifier operating at these frequencies.