Memory effect and statistical characterization of pulsed vacuum microdischarge breakdowns between palladium electrodes from 500 nm up to 10 m

The understanding of microgaps breakdown phenomena at controlled laboratory conditions represents an important prerequisite in the development of future micro -plasma technologies. The present work is focused on the observation of the electrical discharge parameters of the pulsed vacuum breakdown between palladium electrodes. The quasi -homogeneity of the generated fields was achieved using a plane -to -sphere geometry of the electrodes separated from 0.5 to 10 mu m. The first part of the study covers the conditioning process of the electrodes, including a comparison of the pair -virgin and single -virgin electrode configurations. A detailed statistical analysis of the discharge parameters, such as the breakdown voltage, the duration and the energy released during a pulse, and minimal power for maintaining the discharge is provided for different gap configurations for a voltage ramp speed of 107 kV/s. The analysis with respect to breakdown voltage yielded the observation of the memory effect between subsequent breakdowns.