• 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 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 $CF_4$.

• 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.

• 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.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.382-389
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• 1985

The effect of plasma operational parameters for the determination of rare earth elements(REE) by means of inductively coupled plasma(ICP) spectrometry was investigated. While the increase in the flow rate of carrier gas argon enhanced the sensitivity and lowered the detection limit, significant ionization interferences were observed. The decrease in RF power increased the signal to background ratio. The observation point showing the lowest ionization interference was slightly higher than the position where the spatial profile of the analyte reached the maximum. The detection limits of the spectral lines commonly used for the determination of REE were measured and the spectral lines relatively free from spectral interferences were chosen.

• Journal of the Korean Vacuum Society
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• v.9 no.2
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• pp.102-109
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• 2000

It is difficult to meet the cleanliness requirement of $10^{10}/\textrm{cm}^2$ for the giga level device fabrication with mechanical cleaning techniques like scrubbing which is widely used to remove the particles generated during Chemical Mechanical Polishing (CMP) processes. Therefore, the second cleaning process is needed to remove metallic contaminants which were not completely removed during the mechanical cleaning process. In this paper the experimental results for the removal of the metallic contaminants existing on the wafer surface using remote plasma $H_2$ cleaning and UV/$O_3$ cleaning techniques are reported. In the remote plasma $H_2$ cleaning the efficiency of contaminants removal increases with decreasing the plasma exposure time and increasing the rf-power. Also the optimum process conditions for the removal of K, Fe and Cu impurities which are easily found on the wafer surface after CMP processes are the plasma exposure time of 1min and the rf-power of 100 W. The surface roughness decreased by 30-50 % after remote plasma $H_2$ cleaning. On the other hand, the highest efficiency of K, Fe and Cu impurities removal was achieved for the UV exposure time of 30 sec. The removal mechanism of the metallic contaminants like K, Fe and Cu in the remote plasma $H_2$ and the UV/$O_3$ cleaning processes is as follows: the metal atoms are lifted off by $SiO^*$ when the $SiO^*$is evaporated after the chemical $SiO_2$ formed under the metal atoms reacts with $H^+ \; and\; e^-$ to form $SiO^*$.

• 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).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.8
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• pp.607-612
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• 1998

RF HPCVD(Helicon Plasma Chemical Vapor Deposition) has been successfully constructed for diamond thin films. The system consists of plasma generation tube, deposition chamber, pumping lines for gas system. A mixture of $CH_4 and H_2$is used for reaction. Two thermocouples, a quartz tube surrounded by a RF antenna and a magnet, and a high temperature heater were set up in the deposition chamber. The process for the thin film diamond deposition has been carried put in a high vacuum system at a substrate temperature of $800^{\circ}C$, and pressure of 5 mtorr. It is also demonstrated. that the RF HPCVD system has advantages for controlling deposition parameters easily.

• Journal of the Korean Chemical Society
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• v.43 no.2
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• pp.182-192
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• 1999

The new GD/ICP-AES quick change over system has been developed and characterized. Within less than 15 minutes, ICP-AES could be switched to GD-AES and vise a versa. As a result, both solid and liquid samples could be analyzed in a very short period of time by the ICP/GD-AES quick change over system developed in our laboratory. The influences of the experimental variables, such as flow rate of coolant gas, flow rate of auxiliary gas, flow rate of sample carrier gas, sampling depth, orifice size of sampling cone, and rf (radio frequency) power on emission intensity have been presented. The detection limits of Cd(I) 228.8 nm, Mn (II) 257.61 nm, and Fe(II) 259.95 nm were found to be 3.86, 1.49, and 5.79 ppb, respectively. And linealities of the calibration curves were measured to be unity.

• Journal of the Korean Vacuum Society
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• v.15 no.3
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• pp.259-265
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• 2006

We measured sputtering yield of RF $O_2-plasma$ treated MgO protective layer for AC-PDP(plasma display panel) using a Focused ion Beam System(FIB). A 10 kV acceleration voltage was applied. The sputtering yield of the untreated sample and the treated sample were 0.33 atoms/ion and 0.20 atoms/ion, respectively. The influence of the plasma-treatment of MgO thin film was characterized by XPS and AFM analysis. We observed that the binding energy of the O 1s spectra, the FWHM of O 1s spectra and the RMS(root-mean-square) of surface roughness decreased to 2.36 eV, 0.6167 eV and 0.32 nm, respectively.