Transition from Townsend to radio-frequency homogeneous dielectric barrier discharge in a roll-to-roll configuration

Journal Article · Tue Jun 28 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4953389· OSTI ID:22596662

Bazinette, R. ^[1]; Paillol, J. ^[2]

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1. CNRS-PROMES, Rambla de la Thermodynamique, 66100 Perpignan (France)
2. SIAME, Université de Pau et des Pays de l'Adour, Pau (France)

The aim of this paper is to better understand the transition from Townsend to radio-frequency homogeneous dielectric barrier discharge (DBD) at atmospheric pressure. The study is done in an Ar/NH{sub 3} Penning mixture for an electrode configuration adapted to roll-to-roll plasma surface treatment. The study was led in a frequency range running from 50 kHz up to 8.3 MHz leading to different DBD modes with a 1 mm gas gap: Glow (GDBD), Townsend (TDBD), and Radio-frequency (RF-DBD). In the frequency range between TDBD and RF-DBD, from 250 kHz to 2.3 MHz, additional discharges are observed outside the inter-electrode gas gap. Because each high voltage electrode are inside a dielectric barrel, these additional discharges occur on the side of the barrel where the gap is larger. They disappear when the RF-DBD mode is attained in the 1 mm inter-electrode gas gap, i.e., for frequencies equal or higher than 3 MHz. Fast imaging and optical emission spectroscopy show that the additional discharges are radio-frequency DBDs while the inter-electrode discharge is a TDBD. The RF-DBD discharge mode is attained when electrons drift becomes low enough compared to the voltage oscillation frequency to limit electron loss at the anode. To check that the additional discharges are due to a larger gas gap and a lower voltage amplitude, the TDBD/RF-DBD transition is investigated as a function of the gas gap and the applied voltage frequency and amplitude. Results show that the increase in the frequency at constant gas gap or in the gas gap at constant frequency allows to obtain RF-DBD instead of TDBD. At low frequency and large gap, the increase in the applied voltage allows RF-DBD/TDBD transition. As a consequence, an electrode configuration allowing different gap values is a solution to successively have different discharge modes with the same applied voltage.

• OSTI ID: 22596662
• Journal Information: Journal of Applied Physics, Vol. 119, Issue 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMMONIA
AMPLITUDES
ANODES
ATMOSPHERIC PRESSURE
COMPARATIVE EVALUATIONS
CONFIGURATION
DIELECTRIC MATERIALS
DIFFUSION BARRIERS
ELECTRIC POTENTIAL
ELECTRON DRIFT
ELECTRON LOSS
EMISSION SPECTROSCOPY
KHZ RANGE
MHZ RANGE 01-100
RADIOWAVE RADIATION
SURFACE TREATMENTS