• Journal of Korean Vacuum Science & Technology
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• v.6 no.1
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• pp.16-21
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• 2002

Ti-0 film is a kind of biocompatible surface materials. In this paper, a new method, glow discharge plasma oxidizing, has been used in synthesizing Ti-O gradient films on Ti6A14V substrates. The effects of ion bombardment and process parameters on the structures of titanium oxide layers have been investigated. The results demonstrate that DC glow plasma oxidizing is more efficient in preparation of dense, hard, and high adhesive Ti-O biomedical films on titanium and its alloys. Samples treated by this method show higher hardness values than by others. Especially, in the condition of hollow cathode discharge, the ion bombardment enhances ionization of oxygen, promotes the oxygen permeation and facilitates the formation of the oxide of low valence states of titanium.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.489-489
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• 2012

The vibrational distribution of $N_2$ (B, v') in after-glows in $N_2$ RF flowing plasma was investigated. The optical emission of the after-glow was studied as function of distance from plasma. In a tube 2.1 cm, the gas pressure varied 8 Torr with 1000sccm nitrogen gas flowing late.. The discharges were excited by two ring-electrode powered by RF 13.56 MHz 100 Watt. $N_2$ (B, v') vibrational distribution was analyzed to see depends of position in after-glow. Dissociation rate of $N_2$ varied showing maximum in the late after-glow region. We studied $N_2$ RF capacitive flowing plasmas and afterglows by emission spectroscopy and by NO titration to determine the density of N-atoms.

• YAKHAK HOEJI
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• v.39 no.4
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• pp.427-432
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• 1995

The plasma oscillation has been observed in an argon pressure between a tungsten anode and cathode consisting of an aqueous conducting solution. The effects of experimental parameters on the electrical characteristics of the glow discharge have been studied. The experimental parameters include the anode-cathode distance, pressure, methanol flow rate, and cathode materials. The glow discharge with liquid cathode and solid anode showed the potential sensitive detector for HPLC

• Journal of the Korean Chemical Society
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• v.50 no.1
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• pp.14-22
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• 2006

the basic model of chemical reactor using glow discharge, we used cathode discharge cell with vacant cavity in the middle. Currently glow discharge is widely studied as a radiation source or atomization device in atomic spectroscopy and remarkable technological achievements are made through the graft with other analysis devices such as microanalysis and steel analysis.1 Additionally, as the characteristics of basic glow discharge and radiation have been reviewed many times, those results could be used in this experiment.2-3 In 1993, an article regarding the treatment of poisonous gas in the air using low temperature plasma was published. According to this article, if DC Glow Discharge is used under continuous atmospheric flow, poisonous gases such as SO2 and NO can be removed.4 Based on those findings, we designed highly efficient reactor where stable air plasma is composed and all air flow pass the negative glow area passing through the tube. It was observed that the cathode tube type glow discharge developed in this study would be economical, easy to use and could be used as radiation source as well.

• Analytical Science and Technology
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• v.15 no.6
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• pp.502-508
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• 2002

See-through hollow cathode glow discharge cell has been developed for the trace analysis of metal ions. The systems consists of new glow discharge cell improved the cooling system. In the case of previous type of hollow cathode glow discharge cell, it had been utilized for the trace analysis of metal ions but it had a problem that the plasma becomes unstable by air-cooled device. In this study, the modified hollow cathode glow discharge cell has been developed in order to minimize the problem associated with the air-cooled device. thus the stability of the plasma with water-cooling device has been improved and also the higher plasma temperature has been measured. The fundamental characteristics of modified systems have been investigated. And the discharge parameters, such as discharge pressure, material, and diameter of cathode, have been studied to find optimum discharge conditions.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.3
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• pp.478-484
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• 1994

Facing target dc sputtering system developed by Hoshi et al. has simple configuration and high deposition rate under moderate substrate temperature in the range of pressure 5x10S0-4T - 1x10S0-2T torr. In this system, magnetic field should be applied perpendicular to the target surface in order to confine high energy secondary electrons between two targets. Because of this magnetic field, the glow discharge characteristics are very different from dc planar diode system showing some unstable discharge region. In this paper, the glow discharge characteristics of this system have been studied under the condition of Ti targets with Ar-NS12T(10%) as working gas. It is found that this system has stable discharge region under the discharge current density of 15-30(mA/cmS02T). The plasma density and electron temperature are in the range of 10S010Y - 10S011T(CMS0-3T) and 2.5-5(eV), respectively.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1838-1840
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• 1996

In order to study the relationship between the physical properties of glow discharge plasma and the physical behavior of TiN thin film, electrical characteristics of RF discharge plasma driven at 13.56MHz in a parallel-plate electrode system were measured. Plasma parameters, such as electron density and temperature, are also studied since they may be considered as one of the very important factors deciding the physical properties of TiN thin film under given conditions of applied biasd voltage and pressure. The TiN thin film were fabricated over a wide range of discharge conditions, and some of the general relationships between the measured plasma parameters and the properties of TiN thin film were discussed.

• Journal of the Korean Vacuum Society
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• v.4 no.S2
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• pp.49-57
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• 1995

At present the processes of boronizing have been mostly studied in a plasma from gaseous compounds containing the impregnating element and are in an industrial use. These have been investigated by a variety of works in a glow discharge with different mixture ratios of $B_2H_6$ and $H_2$ as well as $BCl_3$ and $H_2$. The active atomosphere has been diluted by Ar or some other inert gas in order to enhance control of boron potential and to reduce the ignition voltage of the glow discharge. The Control of gaseous atomosphere is essential to a boride layer in plamsa boronizing treatment. The boride formation is required to make the workpiece surface saturated with boron content. The present study considers the efficiency of plasma boronizing reactions and the morphology of boride layer under various plasma conditions

• Proceedings of the Korean Vacuum Society Conference
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• 2001.07a
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• pp.164-164
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• 2001

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.406-414
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• 2010

A novel polyacrylamide grafted hydrous ferric oxide adsorbent composite has been synthesized by using glow discharge electrolysis plasma. To optimize the synthesis conditions, the following parameters were examined in detail: applied power, discharge time, post polymerization temperature, post polymerization time, amount of crosslinking agent and hydrous ferric oxide gel added and so on. The adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The removal percentage of the adsorbent in Pb(II) solution was examined and the data obtained showed that the adsorbent composite has a high capacity for lead ion. For the use in wastewater treatment, the thermodynamic and kinetic of Pb(II)-capture were also studied. Results indicated that the adsorption reaction was a spontaneous and an endothermic process, and it seems to be obeyed a pseudo-secondorder rate model. Moreover, the adsorption isotherm of Pb(II)-capture is following the Langmuir and Freundlich isotherm models.