High-efficiency microwave oscillations from Si avalanche diodes

High-efficiency microwave oscillations have been observed in Si p¿n and p¿n¿n+ diodes under pulsed conditions. At about 25 mA reverse-bias current, a sudden decrease in voltage across the diode and an increase in bias current are observed, giving peak output power of 10¿20 W and efficiency up to 30% between 1 and 3 GHz.