MILLIMETER-WAVE HETEROJUNCTION FET MONOLITHIC INTEGRATED-CIRCUITS FOR COMPACT COMMUNICATION-SYSTEMS

This paper describes V-band monolithic integrated circuits utilizing high f(max) N-AIGaAs/InGaAs/N-AlGaAs double doped double heterojunction FETs. A high gain and high efficiency amplifier and an oscillator with low phase noise have been demonstrated. The 0.15 mu m T-shaped gate HJFET with optimized recess distance from the gate to the drain edge of 0.4 pm has a high f(max) of 220 GHz and a high maximum drain current of 700 mA/mm with - 10 V gate breakdown voltage. A single-stage 60 GHz-band amplifier has achieved 8.4 dB small signal gain with good input and output impedance matching. High power-added-efficiency of 25.6% with the output power of 15.7 dBm at 61.2 GHz has been obtained at 3 V drain bias. The maximum output power obtained is 16.4 dBm (43.7 mW). A monolithic oscillator with a series feedback topology has exhibited 4.5 dBm output power with the oscillation frequency of 50.5 GHz. The phase noise is -97 dBc/Hz at 1 MHz off-carrier, which is relatively low for the free running oscillator. The V-band MMICs are very promising for applications to compact communication systems.