Wide-pressure-range coplanar dielectric barrier discharge: Operationalcharacterisation of a versatile plasma source

• Published in: Physics of plasmas 2017-01, Vol.24 (1)
• Main Authors: Čech, J, Bonaventura, Z, Sťahel, P, Zemánek, M, Dvořáková, H, Černák, M
• Format: Article
• Language: English
• Subjects: Breakdown; Dielectric barrier discharge; Dielectrics; Electric potential; Gas pressure; Half spaces; Plasma; Plasma physics; Thickness
• ISSN: 1070-664X; 1089-7674

Many plasma applications could benefit from the versatile plasma source operable at awide-pressure-range, e.g., from the fraction of Pa to the super-atmospheric conditions. Inthis paper, the basic characteristics of wide-pressure-range plasma source based on thecoplanar dielectric barrierdischarge is given. The operational characteristics of thisplasma sourcewere measured innitrogen at pressures ranging from 101 Pa (resp. 10−4 Pa) to105 Pa. Measurements of the plasma geometry, breakdown voltage, andmicro-discharges' behaviour revealed three operational regimes of this plasma source: “high pressure,”“transitional” and “low-pressure” with vague boundaries at the pressures of approx.10 kPa and 1 kPa. It was found that the plasma layer of coplanar dielectric barrier dischargecould be expanded up to several centimetres to the half-space above the planardielectricbarrier when the gas pressure is reduced below 1 kPa, which provides an outstanding space totailor the sourcefor the specific applications. The proposed model of an effective gap distance in thePaschen breakdown criterion enabled us to explain the discharge behaviourfitting the experimental breakdown voltage data in the whole studied pressure range. Underthe filament-forming conditions, i.e., at the pressure range from approx. 1–100 kPa, the activeplasmavolume could be varied through the micro-discharges' lateral thickness scaling with theinverse of the square-root of the gas pressure.