• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.4
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• pp.19-26
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• 2002

A chamber enduring 3,000 bars and an electrical high voltage power system have been designed and installed for studying the characteristics of the plasma produced in electro-thermal chemical propulsion system. In order to test the structural characteristics, polyethylene injectors were used which have 4 or 6 mm inner diameter and several lengths from 15 to 70 mm. The capacitors were charged at the voltages of 5.2, 7.3 and 10.4 kV which correspond to 5.58, 11 and 22.3 kJ in charging energy. The observed resistivities of the plasma injector are close to those predicted by a theoretical model that describes the plasma resistivity according to high current density.

• Explosives and Blasting
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• v.16 no.3
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• pp.35-48
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• 1998

An overview of the plasma rock fragmentation system, the first commercial application of plasma blasting, is presented. Plasma blasting is based on the fast delivery of stored electrical energy to fracture the rock. The capacitor bank, switching device, cable and blasting electrode employed in the system are described. Utilization of the chemical energy delivered from the electrolyte and the development of a large charge transfer switch using pseudospark enabled the commerciailzaion. The vibration and noise level of the blasting is acceptable in the most ground breaking.

• Fibers and Polymers
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• v.2 no.1
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• pp.152-156
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• 2001

Three different silicone polymer systems, such as aminofunctional, epoxyfunctional, and hydrophilic epoxyfunctional silicone polymers, were applied onto plasma pretreated wool fabric to improve the dimensional properties. The results showed that the plasma pretreatment modified the cuticle surface of the wool fiber and increased the reactivity of wool fabric toward silicone polymers. Felting shrinkage of plasma and silicone treated wool fabric was decreased with different level depending on the applied polymer system. Fabric tear strength and hand were adversely affected by plasma treatment, but these properties were favorably restored on polymer application. Therefore, it has been concluded that the combination of plasma and silicone treatments can achieve the improved dimensional stability, and better performance properties of wool fabric. The surface smoothness appearances of treated fabrics were measured using a new evaluation system, which showed good correspondence with the results of KES-FB4 surface tester.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.282-284
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• 2006

UV lamp systems have been used for cleaning of display pannels of TFT LCD or Plasma Display Pannel (PDP). However, the needs for high efficient cleaning and low cost made high voltage plasma cleaning techniques be developed and improved. In this paper, 3kW high voltage plasma power supply system was developed for LCD cleaning. The 3-phase input voltage is rectified and then inverter system is used to make a high frequency pulse train, which is rectified after passing through a high-power transformer. Finally, bi-directional high voltage pulse switching circuits are used to generate the high voltage plasma.

• Applied Science and Convergence Technology
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• v.23 no.4
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• pp.169-178
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• 2014

Fluid model based numerical analysis is done to simulate a low damage etch back system for 20 nm scale semiconductor fabrication. Etch back should be done conformally with very high material selectivity. One possible mechanism is three steps: reactive radical generation, adsorption and thermal desorption. In this study, plasma generation and transport steps are analyzed by a commercial plasma modeling software package, CFD-ACE+. Ar + $CF_4$ ICP was used as a model and the effect of reactive gas inlet position was investigated in 2D and 3D. At 200~300 mTorr of gas pressure, separated gas inlet scheme is analyzed to work well and generated higher density of F and $F_2$ radicals in the lower chamber region while suppressing ions reach to the wafer by a double layer conducting barrier.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.32-36
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• 1992

An ECR plasma apparatus is designed and constructed. The gradient of magnetic field in microwave cavity was adjusted to provide an ECR plasma stream by electro magnetic lenz system. Employing a yoke arround the electro magnets, the magnetic field intensity was increased by 50% with the same electric current. Characteristics of the ECR plasma discharged in the apparatus were investigated by Langmuir probe method. The variations of electron temperature and electron density along chamber axis were analysed.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1712-1718
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• 2014

Experimental analysis according to the plasma actuator design variables was performed in order to verify the effects of sliding discharge plasma on aerodynamic drag reduction of a high-speed train. For the study, sliding discharge plasma actuator and high-frequency, high-voltage power supply were developed and experimented to figure out the best design variables for highest ionic wind velocity which could reduce the drag force. And then, 5% reduced-scale model of a high-speed train was built for wind tunnel test to verify it. From the results, it was confirmed that sliding discharge plasma had contribution to reduce the drag force and it had the potential to be applied to real-scale trains.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.271-276
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• 2011

We investigated the possibility of introducing functional groups without damaging surface polymeric chains through the treatment of a polypropylene(PP) film immersed in liquid phase using an atmospheric pressure plasma with large area. The ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate: $[BMIM]^{+}[BF_{4}]^{-}$- was successfully applied for generating stable plasmas in the plasma-solution system. We successfully treated the film surface using the plasma-solution system and confirmed various oxygen-containing functional groups formed on the surface of PP film. The surface free energy of PP film was increased with increasing plasma treatment time and power. It also showed a maximum value at the PP sample treated in the ionic liquid solution of 1.5 M. ATR-FTIR analyses revealed the increase of various carbonyl groups(1,726 $cm^{-1}$, 1,643 $cm^{-1}$) and OH groups$(3,100{\sim}3,500\;cm^{-1})$ after plasma treatment of PP film, and XPS also supported the ATR-FTIR result.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.300-303
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• 1987

A microwave plasma generating system has been designed to study the properties of plasma. A microwave(2.45GHz) generated by the magnetron is transmitted to the cylindrical cavity through the the rectangular wave guide to generate hydrogen plasma. The electron temperature and the plasma density are measured by the Double Langmuir probe. A dilectric such as alumina is heated by the microwave add plasma. The surface temperature varies with the neutral gas pressure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.12
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• pp.2179-2183
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• 2007

In this paper, to produce sheet plasma with high density for ion plating, we designed magnetic circuit of ion plating device consisting of solenoid coil and rectangular permanent magnet. And, we analyzed the effects of the magnetic field distribution using FEM (Finite Element Methode). Additionally, we made a sputtering system including ion plating technique on the basis of the design and verified the possibility of the sheet plasma application for advanced sputter system.