Germanium epitaxial mesa diodes for a 6 GHz, 1/2-watt CW avalanche oscillator

Germanium epitaxial mesa diodes developed for a radio relay communications application are described. These diodes are capable of providing 1/2-watt CW at 25°C. in the common carrier frequency band at 6 GHz. Stringent noise requirements in radio relay communication systems make it expedient to use germanium. However, the relatively poor thermal conductivity of germanium in conjunction with the high power densities involved have made it mandatory to design for high efficiency, high junction operating temperature, and low thermal impedance.