• 한국가시화정보학회지
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• 제19권3호
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• pp.123-129
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• 2021

Many plants and animals in nature have superhydrophobic surfaces. This superhydrophobic surface has various properties such as self-cleaning, moisture collection, and anti-icing. In this study, the superhydrophobic properties of PTFE surface were treated by plasma etching. There were four important factors that changed the surface properties. Micro-sized protrusions were formed by plasma etching. The most influential parameter was RF Power. The contact angle of the pristine PTFE surface was about 113.8°. The maximum contact angle of the surface after plasma treatment with optimized parameters was about 168.1°. In this case, the sliding angle was quite small about 1°. These properties made it possible to remove droplets easily from the surface. To verify the self-cleaning effect of the surface, graphite was used to contaminate the surface and remove it with water droplets. Graphite particles were easily removed from the optimized surface compared to the pristine surface. As a result, a surface having water repellency and self-cleaning effects could be produced with optimized plasma etching parameters.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권7호
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• pp.424-432
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• 2000

The plasma surface treatment, using hydrogen gas, of the silicon wafer was investigated as a pretreatment for the application to silicon-on-insulator (SOI) wafers using the silicon direct bonding technique. The chemical reactions of hydrogen plasma with surfaces were used for both the surface activation and the removal of surface contaminants. As a result of exposure of silicon wafer to the plasma, an active oxide layer was formed on the surface, which was rendered hydrophilic. The surface roughness and morphology were estimated as functions of plasma exposing time as well as of power. The surface became smoother with decreased incident hydrogen ion flux by reducing plasma exposing time and power. This process was very effective to reduce the carbon contaminants on the silicon surface, which was responsible for a high initial surface energy. The initial surface energy measured by the crack propagation method was 506 mJ/m2, which was up to about three times higher than that of a conventional RCA cleaning method.

• Macromolecular Research
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• 제12권6호
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• pp.608-614
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• 2004

Isotactic polypropylene (PP) surfaces were modified with argon and oxygen plasmas using a radio­frequency (RF) glow discharge at 240 mTorr and 40 W. The changes in topography and surface structure were investigated by atomic force microscopy (AFM) in conjunction with specular reflectance of infrared (IR) microspectroscopy. Under our operating conditions, the AFM image analysis revealed that longer plasma treatment resulted in significant ablation on the PP surface, regardless of the kind of plasma employed, but the topography was dependent on the nature of the gases. Specular reflectance IR spectroscopic analysis indicated that the constant removal of surface material was an important ablative aspect when using either plasma, but the nature of the ablative behavior and the resultant aging effects were clearly dependent on the choice of plasma. The use of argon plasma resulted in a negligible aging effect; in contrast, the use of oxygen plasma caused a noticeable aging effect, which was due to reactions of trapped or isolated radicals with oxygen in air, and was partly responsible for the increased surface area caused by ablation. The use of oxygen plasma is believed to be an advantageous approach to modifying polymeric materials with functionalized surfaces, e.g., for surface grafting of unsaturated monomers and incorporating oxygen-containing groups onto PP.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.38.1-38.1
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• 2009

Plasma etching is an essential process for electronic device industries and the particulate contamination during plasma etching has been interested as a big issue for the yield of productivity. The oxynitride glasses have a merit to prevent particulate contamination due to their amorphous structure and plasma etching resistance. The YSiAlON oxynitride glasses with increasing nitrogen content were manufactured. Each oxynitride glasses were fluorine-plasma etched and their plasma etching rate and surface roughness were compared with reference materials such as sapphire, alumina and quartz. The reinforcement mechanism of plasma etching resistance of the YSiAlON glasses studied by depth profiling at plasma etched surface using electron spectroscopy for chemical analysis. The plasma etching rate decreased with nitrogen content and there was no selective etching at the plasma etched surface of the oxynitride glasses. The concentration of silicon was very low due to the generation of SiF4 very volatile byproduct and the concentration of aluminum and yttrium was relatively constant. The elimination of silicon atoms during plasma etching was reduced with increasing nitrogen content because the content of the nitrogen was constant. And besides, the concentration of oxygen was very low on the plasma etched surface. From the study, the plasma etching resistance of the glasses may be improved by the generation of nitrogen related structural groups and those are proved by chemical composition analysis at plasma etched surface of the YSiAlON oxynitride glasses.

• 펄프종이기술
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• 제44권1호
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• pp.31-36
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• 2012

In the previous study, the possibility of modifying the surface properties of base paper with plasma treatment was evaluated. It was shown that only the hydrophilic properties of the base paper surface was increased while there was no changes in physical and optical properties. Only the surface of the plasma treated side was modified. In this study, the effect of plasma treatment on binder migration was elucidated. The base paper was plasma treated with various voltage and then the plasma treated base papers were coated with varying coated weight. The surface strength of the coated paper (dry and wet pick) was increased with plasma treatment, which implies that the plasma treatment of base paper can inhibit the binder migration.

• 전기학회논문지
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• 제62권3호
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• pp.376-379
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• 2013

Multi-walled carbon nanotubes (MWCNTs) were synthesized using catalytic chemical vapor deposition (CVD) method. Oxygen plasma treatment was applied to modify surface state of the CNTs synthesized for improvement of field emission performance. Surface state of the plasma treated CNTs was studied by X-ray photoelectron spectroscopy (XPS). The surface states of the CNTs were changed as a function of plasma treatment time. The oxygen related carbon shift was moved toward higher binding energy with the plasma treatment time. This result implies that the oxygen plasma treatment changes the surface state effectively. While any shift in carbon 1s peak was not detected for the as grown CNTs, oxygen related carbon shift was detected for the plasma treated CNTs. Carbon shift implies that closed CNT tips were opened by the oxygen plasma and reacted with oxygen species. Since the field emission occurs at pentagons or dangling bonds of the CNT tips, the increase of carbon-oxygen bonds plays an important role in field emission behavior by increasing the number of electron emission sites resulting in improvement of the field emission performance.

• 한국표면공학회지
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• 제34권5호
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• pp.475-480
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• 2001

Diffusion of Cu into the low-k para-xylene based plasma polymer (pXPP) thin films deposited by plasma-enhanced chemical vapor deposition using the para-xylene precursor was comparatively measured using various methods. Cu layer was deposited on the surfaces of pXPPs treated by $N_2$ plasma generated in a magnetically enhanced inductively coupled plasma reactor. Diffusion characteristics of Cu into pXPPs were measured using Rutherford backscattering spectroscopy (RBS), secondary ion mass spectroscopy (SIMS), cross-sectional transmission electron microscopy (XTEM), and current-voltage (I-V) measurements for the vacuum-annealed Cu/pXPPs for 1 hour at $450^{\circ}C$ and were compared. The results showed a correlation between the I-V measurement and SIMS data are correlated and have a sensitivity enough to evaluate the dielectric properties but the RBS or XTEM measurements are not sufficient to conclude the electrical properties of low-k dielectrics with Cu in the film bulk. The additional results indicate that the pXPP layers are quite resistant to Cu diffusion at the annealing temperature of $450^{\circ}C$ compared to the other previously reported organic low-k materials.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2008년도 제34회 동계학술대회 초록집
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• pp.287-287
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• 2008

• Environmental Engineering Research
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• 제24권3호
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• pp.412-417
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• 2019

This paper presents the results of using cold plasma to treat surface water for domestic use purpose. Experimental results showed that cold plasma was an effective method for destroying bacteria in water. After treatment with cold plasma, concentration of coliform and Escherichia coli dramatically reduced. Besides, cold plasma significantly removed water odor, increased dissolved oxygen and decreased the concentration of chemical oxygen demand. However, cold plasma significantly raised the concentration of nitrite and nitrate. Other disadvantages of treating with cold plasma were conductivity increase and pH reduction. Pretreatment steps of coagulation, flocculation, sedimentation and sand filtration followed by disinfection with cold plasma exhibited a high efficiency in surface water treatment. All parameters of surface water after treatment by using the prototype satisfied with the allowance standard of domestic water quality.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권12호
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• pp.596-600
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• 2004

In this study, the surface properties of PET film were analyzed after plasma surface treatment. After plasma treatment of surface roughness and XPS were evaluated to analyze the chemical property, while the surface potential decay and surface resistance rate was measured to analyze the electric관 characteristic. When plasma discharge treatment was conducted for less than 10 minutes, the electrical insulating property was improved by evaporation of low molecular weight materials and cleaning of surface. However, when the treatment was conducted for more than 10 minutes, the insulating property was decreased due to excessive discharge energy. Analyses of chemical characteristics showed that 10-minute treatment resulted in increase of C-O and O=C-O bonds. However, when treated for more than 10 minutes. they were relatively decreased.