• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.1
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• pp.114-122
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• 2014

This paper describes a study of the design conditions of a planar surface dielectric barrier discharge (DBD) reactors for generating negative air ions. The capacity of negative air ion generated by the surface DBD reactor is affected by the shape, area ratio and the location of the discharge and induction electrodes of it. To study the optimal design conditions of DBD reactors, the electrodes printed on the substrate of a PCB board is utilized to conduct kind of experiments: the distance of the each electrode along with the X-Y axis, the area ratio of the discharge electrode to induction electrode, and the symmetrical and asymmetrical location of two electrodes. The ion generation capacity is inverse proportional to the gap increases along with X-Y axis. And the optimum ion concentration generated by the ionizer was inspected when the electrodes area ratio was 3 and 5 times of the symmetrical and asymmetrical experimental condition respectively.

• Transactions on Electrical and Electronic Materials
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• v.7 no.4
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• pp.204-209
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• 2006

Photo Resist (PR) ashing process was carried out with the atmospheric pressure- dielectric barrier discharge (ADBD) using $SF_6/N_2/O_2$. Ashing rate (AR) was sensitive to the mixing ratio of the oxygen and nitrogen of the blower type of ADBD asher. The maximum AR of 5000 A/min was achieved at 2% of oxygen in the $N_2$ plasma. With increasing the oxygen concentration to more than 2% in the $N_2$ plasma, the discharge becomes weak due to the high electron affinity of oxygen, resulting in the decrease of AR. When adding 0.5% of SF6 to $O_2/N_2$ mixed plasma, the PR AR increased drastically to 9000 A/min and the ashed surface of PR was smoother compared to the processed surface without $SF_6$. Carbon Fluorinated polymer may passivate the PR surface. It was also observed that the glass surface was not damaged by the fluorine.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2006.10a
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• pp.31-32
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• 2006

• Journal of Industrial Technology
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• v.30 no.A
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• pp.127-132
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• 2010

We analyzed the effects of several process variables on the $SO_2$ removal and particle growth by the dielectric barrier discharge - photocatalysts hybrid process. In this process, $SO_2$ was converted into the ammonium sulfate ($(NH_4)_2SO_4$) particles. The size and crystallinity of ammonium sulfate particles were examined by using TEM and XRD analysis. The dielectric barrier discharge reactor consisted of two zones: the first is for plasma generation and the second is for ammonium sulfate particles formation and growth. The first zone of reactor was filled with glass beads as a dielectric material. To enhance $SO_2$ removal process, the $TiO_2$ photocatalysts were coated on glass beads by dip-coating method. As the voltage applied to the plasma reactor or the pulse frequency of applied voltage increases, the $SO_2$ removal efficiency increases. Also as the initial concentration of $SO_2$ decreases or as the residence time increases, the $SO_2$ removal efficiency increases. $(NH_4)_2SO_4$ particles continue to grow by particle coagulation and surface reaction, moving inside the reactor. Larger particles in site are produced according to the increase of residence time or $SO_2$ concentrations.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.11
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• pp.1587-1591
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• 2015

For a higher definition discharge cell, the method of high speed addressing is necessary. In order to modify the surface charges, the liquefied $TiO_2$ or MgO powder is added on MgO layer in front glass and on the phosphor in rear glass in micro barrier discharge. Both the electro-optical properties and the discharge time lag characteristics are measured from 4 inch. test panel, such as the discharge voltage, current, luminance, luminous efficacy and discharge time lag. As the results, the statistic time lag is improved by about 40 %.

• Journal of electromagnetic engineering and science
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• v.18 no.1
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• pp.52-57
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• 2018

Surface dielectric barrier discharge (SDBD), which is widely used to control turbulence in aerodynamics, has a significant effect on the radar cross-section (RCS). A four-way linearly synthesized SDBD air plasma actuator is designed to bolster the plasma effects on electromagnetic waves. The diffraction angle is calculated to predict the RCS because of the periodic structure of staggered electrodes. The simplified plasma modeling is utilized to calculate the inhomogeneous surface plasma distribution. Monostatic RCS shows the diffraction in the plane perpendicular to the electrode array and the notable distortion by plasma. In comparison, the overall pattern is maintained in the parallel plane with minor plasma effects. The trends also appear in the bistatic RCS, which has a significant difference in the observation plane perpendicular to the electrodes. The peaks by Bragg's diffraction are shown, and the RCS is reduced by 10 dB in a certain range by the plasma effect. The diffraction caused by the actuator and the inhomogeneous air plasma should be considered in designing an SDBD actuator for a wide range of application.

• Clean Technology
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• v.13 no.2
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• pp.115-121
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• 2007

In this study, we analyzed experimently the NO and $SO_2$ removal by the dielectric barrier discharge-photocatalysts hybrid process. The glass spheres were used as a dielectric material for dielectric barrier discharge and the $TiO_2$ photocatalysts were coated onto those spheres by the dip-coating method. The $TiO_2$ particles were coated in the sponge-shape, which has the larger surface area. As the voltage applied to the plasma reactor, the pulse frequency of applied voltage, or the residence time increases, the NO and $SO_2$ removal efficiencies increase. The increase in the supplied concentrations of NO and $SO_2$ leads to the higher energy for NO and $SO_2$ removal and the NO and $SO_2$ removal efficiencies decrease. These experimental results can be used as a basis to design the dielectric barrier discharge-photocatalysts hybrid process to remove NO and $SO_2$.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.95-95
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• 2009

대기압 플라즈마 발생장치를 이용한 식각장비 개발은 낮은 공정단가, 저온 공정, 다양한 표면처리 응용 효과와 같은 이점을 가지고 있어 현재, 많은 분야에서 연구되고 있다. 본 연구에서는, dielectric barrier discharge(DBD) 방식을 이용한 대기압 발생장치를 통해 평판형 디스플레이 제작에 응용이 가능한 $SiO_2$ 층의 식각에 대한 연구를 하였다. $N_2/NF_3$ gas 조합에 $CF_4$ 또는 $C_{4}F_{8}$ gas를 부가적으로 첨가하였다. 이때 N2 60 slm / NF3 600 sccm/CF4 7 slm/Ar 200 sccm의 gas composition에서 최대 260 nm/min의 식각 속도를 얻을 수 있었다.

• Journal of the Korean institute of surface engineering
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• v.53 no.5
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• pp.201-206
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• 2020

A SiOxCy(-H) thin film was synthesized by atmospheric pressure dielectric barrier discharge(APDBD), and a SiO₂-like layer was formed on the surface of the film by oxidation treatment using oxygen plasma. Hexamethylcyclotrisiloxane was used as a precursor for the SiOxCy(-H) synthesis, and He gas was used for stabilizing APDBD. Oxygen permeability was evaluated by forming an oxidized SiOxCy(-H) thin film on a PET film. When the single-layer oxidized SiOxCy(-H) film was coated on the PET, the oxygen gas permeability decreased by 46% compared with bare PET. In case of three-layer oxidized SiOxCy(-H) film, the oxygen gas permeability decreased by 73%. The oxygen permeability was affected by the thickness of the SiO₂-like layer formed by oxidation treatment rather than the thickness of the SiOxCy(-H) film. The excellent corrosion resistance was demonstrated by coating an oxidized SiOxCy(-H) thin film on the silver-coated aluminum PCB for light emitting diode (LED).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.527-528
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• 2012

DBD (Dielectric Barrier Discharge) plasma actuator was designed for aerodynamic drag reduction using plasma flow control, and the drag reduction was measured by wind-tunnel tests using 2D test model. At the zero wind velocity, the plasma flow control had no effect on the drag reduction because the flow separation and surface friction drag were not occurred. At the wind velocity of 2m/s, 9.7% of drag was reduced by the flow separation control. The drag reduction decreased as the wind velocity increased.