• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1555-1559
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• 1997

The thin films were obtained by plasma polymerization of phenyl isothiocyanate. Polymerizations were carried out in rf(13.56[MHz]) glow discharge generated in an inter-electrode capacitively coupled gas flow system. It was found that this monomer produces uniform films with a wide range of thicknesses, from hundreds of nanometers to tens of micrometers. The deposition rate appeared to be dependent on the substrate distance from the monomer inlet. The IR data revealed significant decrease in -NCS groups content in the polymer as compared with the monomer spectrum and indicated for the appearance of new absorption bands corresponding to the -CN and C-H aliphatic groups. The soluble fraction by GC was found to be composed of numerous low molecular-weight compounds.

• Membrane Journal
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• v.15 no.3
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• pp.233-240
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• 2005

Surface modification of polypropylene hollow fiber membranes was performed in order to develop blood-compatibility biomaterials for use in the blood contacting surfaces and oxygenation membranes of a lung assist device (LAD), important medical device even more useful. Blood compatibility of materials was determined by using anticoagulation blood and evaluating formation of blood clots on their surfaces as well as activation of plasma coagulation cascade, platelet adhesion, and aggregation. It was verified that the number of platelets on the silicone coated fibers was significantly lower than that on untreated fiber membrane, indicating improved blood compatibility. It was also found that the polypropylene hollow fiber membranes using plasma treatment exhibited suppression of complement activation in blood compatibility test.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.10
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• pp.1412-1416
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• 2014

We report thin-film organic moisture barriers based on polystyrene(PS) laminates deposition by PECVD for an encapsulation of OLEDs. The organic polystyrene thin-film has the benzene ring structure and high hydrophobic characteristics and it was polymerized by PECVD in dry process. Life time properties of Ca test were obtained 32 minutes at the RF 100W process conditions. From the AFM test, the roughness of multi-layer thin-film was more excellent rather than that of a single-layer thin-film. In addition, 5 layers of the multi-layer film properties were obtained 45 minutes. So that the optical and electrical properties were not affected with these plasma polymerized organic thin-film encapsulation. For life time improvement, the inorganic $Al_2O_3$ thin-film were deposited 5nm using ALD atomic layer deposition. The WVTR(Water Vaper Transmission Rate) value of hybrid thin-film encapsulation in the optimum process conditions was resulted by less than $10-3g/m^2/day$. From the results of experiment, plasma polymerized hybrid encapsulation was suggested as the flexible display applications.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1347-1348
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• 2007

In this paper, ITO gate electrode surface was modified using $O_2$ plasma and organic gate insulating layers were deposited on the ITO surface using plasma polymerization technique. In order to investigate the influence of the plasma coupling method and plasma conditions on the plasma polymerized methyl methacrylate (ppMMA) thin film properties, inductively coupled (ICP) and capacitively coupled plasma (CCP) were used to generate the plasma and the plasma parameters were varied. The ppMMAs were investigated using atomic force microscopy (AFM) and a Fourier Transform Infrared (FT-IR) spectroscopy. Dielectric constants of the ppMMA thin films were investigated using a impedance analyzer (HP4192A, LF Impedance Analyzer). Current-Voltage (I-V) characteristics of the organic thin film transistors (OTFTs) were investigated using a source measurement unit (SMU: Keithley 2612). Proposed method can be applied to dry-process to fabricate OTFTs during overall fabricating steps.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.63-65
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• 1998

1. Introduction : Atmospheric discharge of VOC-contaminated streams in chemical plants and air streams from chemical processes poses a serious environmental problem and entails large financial losses. Such emissions may be reduced by i) adsorption process, ii) absorption process and iii) incineration process. These processes only forbids the air pollutions. Throughout the recent decade, another technique-membrane process has emerged. The separation and recovery of organic vapors by membrane process may have great economic potential. Most of the published research works on the separation of organic vapors from air were performed using silicon rubber membranes. However, it is very difficult to fabricate very thin membranes with less than 1 $u m thickness. Plasma polymerization could be a good technique to generate a thin polymer film. The objective of this work is to find out the optimum condition of plasma polymerization for producing VOC separation membrane. For the objective, composite membranes are prepared through plasma polymerization of hexamethyldisiloxane onto porous substrates under different conditions. The membrane is then subjected to the permeation of permanent gases and VOCs to find the correlations between the physical properties of the penetrant and permeability and selectivity.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.143-146
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• 2002

Unsized AS-4 carbon fibers were etched by RF plasma and then coated via plasma polymerization in order to enhance adhesion to vinyl ester resin. The gases utilized for the plasma etching were Ar, $N_2 and O_2$, while the monomers used for the plasma polymerization coating were acetylene, butadiene and acrylonitrile. The conditions for the plasma etching and the plasma polymerization were optimized by measuring interfacial adhesion with vinyl ester resin via micro-droplet tests. Among the treatment conditions, the combination of Ar plasma etching and acetylene plasma polymerization provided greatly improved interfacial shear strength (IFSS) of 69MPa compared to 43MPa with as-received carbon fiber. Based on the SEM analysis of failure surface and load-displacement curve, it was assume that the failure might be occurred at the carbon fiber and plasma polymer coating. The plasma etched and plasma polymer coated carbon fibers were subjected to analysis with SEM, XPS, FT-IR or Alpha-Step, and dynamic contact angles and tensile strengths were also evaluated. Plasma polymer coatings did not change tensile strength and surface roughness of fibers, but decreased water contact angle except butadiene plasma polymer coating, possibly owing to the functional groups introduced, as evidenced by FT-IR and XPS.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.402-406
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• 2008

A series of random copolymers, composed of 1H,1H,2H,2H-perfluoro decyl methacrylate (FDMA) as a $CO_2$-philic monomer and tert-butyl methacrylate (TBMA) as an acid labile monomer, were synthesized by free radical polymerization. The solubility of copolymers in carbon dioxide, light sensitivity at 365 nm exposure, and photoresist pattern formation properties were investigated. Furthermore, sub micron-sized poly(styrenesulfonate) : poly(3,4-ethylenedioxythiophene) (PSS : PEDOT) conducting polymer patterns were successfully prepared by pattern transfer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5213-5218
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• 2014

Organic memory devices were made using the plasma polymerization method. The memory device consisted of ppMMA(plasma polymerization MMA) thin films as the tunneling and insulating layer, and a Au thin film as the memory layer, which was deposited by thermal evaporation. The organic memory operation theory was developed according to the charging and discharging characteristics of floating gate type memory, which would be measured by the hysteresis voltage and memory voltage with the gate voltage values. The I-V characteristics of the fabricated memory device showed a hysteresis voltage of 26 [V] at 60 ~ -60 [V] double sweep measuring conditions. The programming voltage was applied to the gate electrode in accordance with the result of this theory. A programming voltage of 60[V] equated to a memory voltage of 13[V], and 80[V] equated to a memory voltage of 18[V]. The memory voltage of approximately 40 [%]increased with increasing programming voltage. The charge memory layer charging or discharging according to the theory of the memory was verified experimentally.

• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.70-75
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• 2002

Mycoplasma pneumioniae has a unique genomic composition, cellular biology, and a fastidious nature as the smallest cell-free living organism that lacks a cell wall. Previous studies have suggested that a clinical manifestation of a M. pneumoniae infection is a consequence of a host immune response, particularly involving cellular immunity. Adenosine deaminase (ADA) is the main T-lymphocyte enzyme, and its activity is high in diseases where cellular immunity is stimulated. Therefore, its activity is useful for diagnosing a tuberculous pleural effusion. A pleural effusion is found in 5-20% of Mycoplasma pneumonia patients. However, there are few reports of high ADA activity in a mycoplasmal pleural effusion. Here we report a case of Mycoplasma pneumoniae infection established by a polymerase chain reaction and serologic tests, accompanying high ADA activity in a pleural effusion.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.488-492
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• 2002

The purpose of this study was to evaluate the effectiveness of plasma arc curing (PAC) unit for composite and compomer curing. To compare its effectiveness with conventional quartz tungsten halogen (QTH) light curing unit, the polymerization shrinkage rates and amounts of three composites (Z100, Z250, Synergy Duo Shade) and one compomer, that had been light cured by PAC unit or QTH unit, was compared using a custome made linometer. The measurement of polymerization shrinkage was peformed after polymerization with either QTH unit or PAC unit. In case of curing with the PAC unit, the composite was light cured with Apollo 95E for 6s, the power density of which was recorded as 1350 mW/$\textrm{cm}^2$ by Coltolux Light Meter. For light curing with QTH unit, the composite was light cured for 30s with the XL2500, the power density of which was recorded as 800 mW/$\textrm{cm}^2$ by Coltolux Light Meter. The amount of linear polymerization shrinkage was recorded in the computer every 0.5s for 60s. Ten measurements were made for each material. The amount of linear polymerization shrinkage for each material in 10s and 60s which were cured with PAC or QTH unit were compared with t test. The amount of polymerization shrinkage in the tested materials were compared with 1way ANOVA with Duncan's multiple range test. As for the amounts of polymerization shrinkage in 60s, there was no difference between PAC unit and QTH unit in Z250 and Synergy Duo Shade. In Z100 and Dyract AP, it was lower when it was cured with PAC unit than when it was cured with QTH unit (p<0.05). As for the amounts of polymerization shrinkage in 10s, there was no difference between PAC unit and QTH unit in Z100 and Dyract AP. The amounts of polymerization shrinkage was significantly higher when it was cured with PAC unit in Z250 and Synergy Duo Shade (p<0.05). The amounts of polymerization shrinkage in the tested materials when they were cured with QTH unit were Z250 (6.6um) < Z100 (9.3um), Dyract AP (9.7um) < Synergy Duo Shade (11.2um) (p<0.05). The amount of polymerization shrinkage when the materials were cured with PAC unit were Dyract AP (5.6um) < Z100 (8.1um), Z250(7.0um) < Synergy Duo Shade (11.2um) (p<0.05).