CHAOTIC FLUCTUATIONS AND A PLASMA-DENSITY CHANGE AT THE BEGINNING OF MICROWAVE DISCHARGES

Nonmonotonic behavior of plasma density was observed as the output pow er of a magnetron increased. The behavior was classified into four ste ps: The electron density increased; became nearly constant; increased again; and finally saturated. In the first two steps, ion saturation c urrent showed chaotic fluctuations. The amplitude of these fluctuation s decreased as the output power of the magnetron increased, and disapp eared at the final step.