High-efficiency operation of GaAs Schottky-barrier IMPATTs

CW GaAs Schottky-barrier IMPATT oscillators have been fabricated using nichrome as the barrier metal. Several of the oscillators exhibited CW efficiencies ranging from 15 percent to 17.5 percent in C and X band. The best result was 19-percent efficiency in X band from an oscillator which produced 700 mW of output power. Noise performance which is comparable to those of transferred electron oscillators and reflex klystrons has also been observed.