Streak image observations of vacuum arc spots in a magnetically steered arc plasma source

The physics of vacuum arc spot operation remains subject of research due to difficulties associated with short characteristic times (ns to μs) and short length scales (μm or even smaller). The advancement of modern plasma diagnostic technologies may allow us to probe arc spot plasma with higher spatial and temporal resolution than before. In this contribution, we report on the evolution of arc spots using a steered arc plasma source which is in its construction similar to a linear sputtering magnetron: the E x B field is utilized to have some control of spot locations while performing the study. The main plasma diagnostics tool we employ is a streak camera with an image intensifier which allows us to observe the dynamics of the optical emission of arc spots in various sweep time intervals (50 μs, 10 μs, 1 μs, and 500 ns). The observed spot shows self-similar patterns in the emitted light with different sweep times.