• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.15-20
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• 1999

Visible light spectrum emitted from $H_2$ plasma in the parallel plate reactor using a commercial electric power are investigated by optical emission spectroscopy. Intensity of visible light is measured as a function of $H_2$ pressure and discharging power, and the intensity is compared with plasma density measured with the probe. As a result, the intensity is affected by plasma density and the plasma density is controlled the $H_2$ pressure and the discharging power.

• Journal of the Korean Ceramic Society
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• v.39 no.4
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• pp.409-412
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• 2002

Under atmospheric pressure, apparently homogeneous and stable plasma can be generated from insulator barrier rf plasma generators each of which has an rf powered cathode and a grounded anode covered with a dielectric insulating material. In order to characterize the generating plasma under atmospheric pressure, some basic characteristic have been evaluated by the Langmuire probe method as well as by optical emission spectroscopy. From the result of plasma characteristics, the generated plasma was verified to be nonequilibrium; T(electron)>T(excitation)>T(gas). High rate Si(100) etching (($1.5{\mu}m$/min) were achieved by using He plasma containing a small amount of $CF_4$.

• Journal of the Korean Vacuum Society
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• v.10 no.4
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• pp.411-415
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• 2001

Using the plasma that we developed to generate a low-temperature plasma at atmospheric pressure, we have investigated the etching possibility of tin oxide $(SnO_2)$ thin films. Hydrogen and methane radicals generated from the plasma were observed and their intensity was found to be dependent on the cathode material by an analysis with optical emission spectroscopy as well as by the plasma impedance. The etching ability of this plasma was evaluated by an emission intensity as well as by the evaluation of impedance using a plasma I-V curve.

• Polymer(Korea)
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• v.31 no.1
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• pp.31-36
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• 2007

It has been reported that the surface properties of the plasma treated material were changed while maintaining its bulk properties. In this study, surface modification of nylon fiber by plasma treatment was tried to attain high water-repellency Nylon fiber was treated with RF plasma under a vacuum system using various parameters such as gas specious, processing time and processing power. Morphological changes by low pressure plasma treatment were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Moreover, the mechanical and inherent properties were analyzed by tensile strength, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The high water-repellency property of nylon fiber was evaluated by a water-drop standard test under various conditions in terms of aging effect. The results showed that the water-repellency of plasma-surface-treated nylon fiber was greatly improved compared to untreated nylon fiber.

• Polymer(Korea)
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• v.30 no.5
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• pp.391-396
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• 2006

It has been reported that plasma treatments are used to modify surface properties of polymers such as adhesivity hydrophobicity and hydrophilicity. Using plasma treatment, interfacial pro-perty can be introduced to a polymer surface without affecting the desired bulk properties of a material. In this study, commercial polyamide66 (PA66) /polyphenylene (PPE) polymer was modified by plasma treatment under a various gas specious for elimination of organic compound and polymer surface property with hvdrophilicity. PA66/PPE polymer with hydrophilicity was treated by RF plasma vacuum system under a various parameter such as gas specious, processing time and partial pressure. Hydrophilicity of PA66/PPE was confirmed by calculation of the surface free energy from contact angle measurement. The highest surface free energy of $50.03 mJ/m^2$ with the lowest contact angle of $14^{\circ}$ was obtained at plasma process power of 100 W, treatment time of 2 min and $Ar/O_2$ gases of 100 and 200 sccm. Moreover the change of organic compounds on the polymer surface was analyzed by fourier transforms infrared spectrometry (FTIR).

• Polymer(Korea)
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• v.29 no.6
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• pp.581-587
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• 2005

Commercial polyurethane film (PU) was modified with Ar plasma ionized in dielectric barrier discharge (DBD) plate-type reactor under atmospheric pressure. We measured the change of the contact angle and the surface fee energy with respect to the plasma treatment conditions such as treatment time, RF-power, and Ar gas flow rate. We also optimized the plasma treatment conditions to maximize the surface peroxide concentration. At the plasma treatment time of 70 sec, the power of 120 W and the Ar gas flow rate of 5 liter per minute (LPM), the best wettability and the highest surface fee energy were obtained. The 1,1 diphenyl-2-picrylhydrazyl (DPPH) method confirmed that the surface peroxide concentration was about 2.1 nmol/$\cm^{2}$ at 80 W, 30 sec, 6 LPM.

• Journal of the Korean Vacuum Society
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• v.13 no.3
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• pp.132-138
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• 2004

We used the self-consistent one-dimensional model applied to FCT algorithm and FEM method in a wire-cylinder type reactor to study the characteristics of corona discharge plasma in air at the atmospheric pressure. At the pulsed do voltage and do voltage, we studied the changes of the characteristic of plasma by computing electron density profile according to the changes of voltage and the size of reactor. The changes of active radius from this result are compared with the data of Peek's. The numerical simulation results for a corona discharge plasma explain the physical mechanism of the discharge process and could be used to obtain the optimized parameters for designing the plasma reactor for pollution abatement.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.53-54
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• 2002

Plasma ignition method has been applied in various fields particularly to the rocket propulsion, pyrotechnics, explosives, and to the automotive air-bag system. Ignition method for those applications should be safe and also operate reliably in hostile environments such as; electromagnetic noise, drift voltage, electrostatic background and so on. In the present study, a semiconductor bridge (SCB) plasma ignition device was fabricated and its plasma characteristics including the propagation speed of the plasma, plasma size, and plasma temperature were investigated with the aid of the visualization of micro scale plasma $(i.e.,\;\leq\;350\;{\mu}m)$, which generated from a Micro-Electro-Mechanical poly-silicon semiconductor bridge (SCB).

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.327-332
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• 1986

Spatial (radial and height) distribution of electron number density is measured for an inductively coupled plasma under five operating conditions: (1) no carrier gas, (2) carrier gas without aerosel, (3) carrier gas with aerosol, (4) carrier gas with desolvated aerosol, and (5) carrier gas with aerosol and excess lithium. A complete RF power mapping of electron density is obtained. The plasma electrons for a typical analytical torch are observed to be hollow at the radial center in the region close to the induction coil, but diffuse rapidly toward the center in the higher region of the plasma. The presence of excess Li makes no significant change in the electron density profiles. The increases in the RF power levels increase the values of electron density uniformly across the radial coordinate.

• Elastomers and Composites
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• v.34 no.4
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• pp.315-320
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• 1999

Surface modification of silicone rubber by low temperature plasma process was investigated to improve quality of silicone EVD tube by reducing tackiness and hydrophobicity. Treatment with nonpolymer-forming plasmas and thin film deposition with polymer-forming plasmas were tried. Tackiness could significantly be reduced, especially by thin film deposition. As a result, the tube became slippery and less vulnerable to contamination in laboratory environment. Inner as well as outer surface of the tube could be changed to be hydrophilic if the plasma contained oxygen. As a result, initial hydrodynamic resistance was reduced. The surface modification did not give any bad influence on mechanical properties of the silicone tube in most cases. Rather, some properties such as Young's modulus, ultimate tensile strength and elongation at break were improved.