Micro dielectric barrier discharges (mDBDs) consist of micro-plasma devices (10-100 lm diameter) in which the electrodes are fully or partially covered by dielectrics, and often operate at atmospheric pressure driven with radio frequency (rf) waveforms. In certain applications, it may be desirable to extract electron current out of the mDBD plasma, which necessitates a third electrode. As a result, the physical structure of the m-DBD and the electron emitting properties of its materials are important to its operation. In this paper, results from a two-dimensional computer simulation of current extraction from mDBDs sustained in atmospheric pressure N 2 will be discussed. The mDBDs are sandwich structures with an opening of tens-of-microns excited with rf voltage waveforms of up to 25 MHz. Following avalanche by electron impact ionization in the mDBD cavity, the plasma can be expelled from the cavity towards the extraction electrode during the part of the rf cycle when the extraction electrode appears anodic. The electron current extraction can be enhanced by biasing this electrode. The charge collection can be controlled by choice of rf frequency, rf driving voltage, and permittivity of the dielectric barrier. V

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Micro-dielectric barrier discharges (mDBDs) are known for being stable, high-pressure and non-thermal plasma sources. mDBD arrays consist of micro-plasma devices (10-100 µm) in which the radio frequency (rf)-excited electrodes are covered by dielectrics. In certain applications, independent control of individual mDBDs in an array is required for charge extraction to treat dielectric surfaces. When using the mDBDs to produce plumes of charged species, there are potential direct or indirect interactions between the mDBD devices. In this paper, we discuss the characteristics of atmospheric mDBD arrays sustained in N 2 with an O 2 impurity using results from a two-dimensional simulation. The device of interest consists of a sandwich structure using layers of dc and rf biased electrodes to help shape the plume. We found that the adjacency of the mDBDs and the dielectric properties of the materials being treated are important to the interactions between mDBDs in the array. Scaling laws are presented for operating characteristics of these mDBD arrays as a function of material properties, geometry, driving voltage waveform and gas mixture.

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