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arXiv · 1104.5579

Ionization wave propagation on a micro cavity plasma array

Alexander Wollny·Torben Hemke·Markus Gebhardt·Ralf Peter Brinkmann·Henrik Boettner·Joerg Winter·Volker Schulz-von der Gathen·Zhongmin Xiong·Mark J. Kushner·Thomas Mussenbrock
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Abstract

Microcavity plasma arrays of inverse pyramidal cavities have been fabricated in p-Si wafers. Each cavity acts as a microscopic dielectric barrier discharge. Operated at atmospheric pressure in argon and excited with high voltage at about 10 kHz, each cavity develops a localized microplasma. Experiments have shown a strong interaction of individual cavities, leading to the propagation of wave-like optical emission structures along the surface of the array. This phenomenon is numerically investigated using computer simulation. The observed ionization wave propagates with a speed of about 5 km/s, which agrees well the experimental findings. It is found that the wave propagation is due to sequential contributions of a drift of electrons followed by drift of ions between cavities seeded by photoemission of electrons by the plasma in adjacent cavities.

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Alexander Wollny, Torben Hemke, Markus Gebhardt, Ralf Peter Brinkmann, Henrik Boettner, Joerg Winter, Volker Schulz-von der Gathen, Zhongmin Xiong, Mark J. Kushner, Thomas Mussenbrock. 2011-04-29. Ionization wave propagation on a micro cavity plasma array. https://doi.org/10.1063/1.3647978

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