A Study of Two-Dimensional Microdischarge Pattern Formation in Dielectric Barrier Discharges

Abstract

Although microdischarges in dielectric-barrier discharges (DBDs) have been studied for the past century, their mutual interaction was explained only recently. This interaction is responsible for the formation of microdischarge patterns reminiscent of two-dimensional crystals. Depending on the application, microdischarge patterns may have a significant influence on DBD performance, particularly when spatial uniformity is desired. This paper presents the results of study of regular microdischarge pattern formation in DBD in air at atmospheric pressure. Experimental images of DBD (Lichtenberg figures) were obtained using photostimulable phosphors. A new method for analysis of microdischarge patterns that allow measuring the degree of pattern regularity was developed. Simulated and experimental patterns were compared using the newly developed method and comparison indicates the presence of interaction between microdischarges. Analysis of microdischarge patterns shows that regularity of the patterns increases with the number of excitation cycles used to produce the pattern.

Discharge Characteristics and Plasma Erosion of Various Dielectric Materials in the Dielectric Barrier Discharges

“…The slope of the I-V curve in Figure 6 corresponds to the |1/Z| of Equation (1). Assuming the sufficient largeness of the Rp (Rp > |1/ωC1|), and without considering the imaginary capacitance, the slope of the I-V curve is as follows: Figure 6 presents the typical I-V characteristics, the so-called filamentary mode [33,34,42,43], in terms of the typical DBD operation with the atmospheric pressure. Since the capacitance is so high between the two short-gap electrodes on the surface of the both-side dielectric layer, a high displacement current is expected even before the ignition with an operation voltage less than the V f .…”

“…Thus, at the V f , the slightly increasing current slope reflects the plasma generation. Under the special operating conditions, usually those of a low-pressure operation, the glow mode is present [42,43]. The latter cases of the I-V characteristics have been analyzed regarding the usual discharge-tube experiments, including the DBD structure with the gases of a low pressure that is approximately several tens of Torr [44][45][46][47].…”

Pattern formation and self-organization in plasmas interacting with surfaces

“…As in other types of systems, pattern formation and self-organization phenomena are also prevalent in plasmas. Different types of pattern formation phenomena have been reported in a wide range of plasmas, such as low-pressure-high-current vacuum arcs [12,13], low-pressure-low-current glow [14], streamer [15], and dielectric barrier [16,17] discharges; high-pressure-lowcurrent glow [18] and dielectric barrier [19,20] discharges; and high-pressure-high-current arc discharges [21][22][23][24].…”

“…The studies of microdischarges in DBD in air at atmospheric pressure by [19] revealed the formation of patterns reminiscent of 2D crystals. These results correlate with those in [117], in which the quasi-crystal patterns are associated to the self-organization of Voronoi tessellations, which may have potential for applications.…”

Electron current extraction from radio frequency excited micro-dielectric barrier discharges

“…14,18 For example, ozone generation and remediation of toxic gases, 19,20 UV/VUV photon sources and polymer functionalization, [21][22][23] and plasma display panels 13,24 are typical DBD applications. Recently, DBDs are also being implemented as plasma sources in biomedical medical applications, 25,26 area-selective surface modification, 1,2,27 investigations of nonlinear behavior, 28 selforganized pattern formation, 29,30 and large arrays of DBDs having apertures of tens of microns as lighting sources. 9,11,12 Our interest is in arrays of DBDs operated at atmospheric pressure which can be used as sources of electron current for patterning dielectric surfaces.…”