On the signal dependence of avalanche noise generation

The influence of ionization in the drift space of an IMPATT diode on the noise generation in the avalanche process is studied. It is found that carrier generation by ionization in the drift space increases the current minima between the current pulses as generated in the avalanche region. The build-up of new avalanche current pulses therefore starts from a higher current level and consequently the behavior is less noisy. The effect of this decrease in noise on the IMPATT-diode oscillator FM noise is estimated.