Discharge dynamics of a micro-structured atmospheric pressure plasma channel

We report on phase and space resolved optical emission spectroscopic combined with electrical measurements on micro-structured plasma channel devices operated close to atmospheric pressure. These devices have confining structures in the range of several 10 $\mu $m and are made up of one linear discharge channel. They consist of a 50 $\mu $m deep channel of triangular cross-section etched into a silicon wafer and Ni electrodes coated at the edges of the channel as electrodes. This type of device is typically operated in rare gas at frequencies in the range of several kHz. Apart from an electrical characterisation investigations on the influence of excitation frequency on the development of pulse bursts are presented. Emission features propagating across the discharge channel are observed. Discharge dynamics are compared to those observed for micro-structured atmospheric pressure plasma arrays with discharge cavities of comparable cross-section. This work is funded by the DFG (FOR 1123 ``Physics of Microplasmas'').