• 멤브레인
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• 제19권1호
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• pp.54-62
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• 2009

부탄올을 투과증발 공정으로 분리하기 위하여 복합공정에 의하여 투과증발막을 제조하였다. 상업용 poly(dime-thylsiloxane) (PDMS) 막을 plasma 처리시키거나, polysulfone, poly(ether imide) 막을 지지체로 사용하여 plasma 처리 및 PDMS 코팅의 복합공정을 적용하였다. 헥산계열과 실란계열 유기 화합물을 사용하여 PDMS막을 plasma 처리하였을 경우 막 표면의 소수성을 증가시켜서 부탄을 선택도가 12.56까지 향상되었다. 반면에 투과량은 막 표면의 소수성 증대와 free volume의 변화로 인해 $1.15kg/m^2{\cdot}hr$까지 감소되어 선택도와 반대의 성향을 나타내었다. 막의 소수성이 증가함에 따라 접촉각과 상대적 sorption 비가 증가하였고, 부탄을 선택도도 향상되었다. PDMS 코팅 용액에서 prepolymer의 함량이 높을수록 부탄올 선택도가 증가하였다. PDMS 코팅과 plasma 처리 공정의 순서에 따른 영향을 조사하였다. 부탄올과 노르말 헥산으로 plasma 처리할 경우 plasma처리, PDMS 코팅 순으로 제조된 막의 분리 성능이 우수하였고 hexamethyldisilane과 hex-amethyldisilazane을 사용한 경우에는 역순으로 제조된 막의 분리 성능이 더 우수한 것으로 나타났다.

• 열처리공학회지
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• 제18권1호
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• pp.24-28
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• 2005

New post plasma nitriding can achieve a high uniformity that have been difficult in DC nitriding and have a high productivity comparable to gas nitriding. However, it has not a enough high nitriding potential for a rapid nitriding, because surface activation or ion etching in the general plasma nitriding cannot be expected. Thus, in this study, the effects of pre-treatments with oxidation and reduction gas have been investigated to improve the nitriding kinetics of post plasma nitriding. An effective pre-treatment consisting of oxidation and reduction resulted in the increase of surface energy of STD 11. This induced the surface hardness and the effective nitriding depth of STD 11. It is thought that the increase of the surface energy and the surface area with pre-treatment promote the nucleation of nitriding layer.

• 한국전기전자재료학회논문지
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• 제23권1호
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• pp.10-13
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• 2010

The plasma processing technologies of thin film deposition and surface treatment technique have been applied to many industrial fields. This study is purposed Large-area uniformity and surface treatment on the stainless substrate. We treat surface of stainless by $CF_4$ plasma. $CF_4$ plasma is generated by using SPM(Scanning plasma method)which is kind a of CVD. Generally, SPM has been used for uniform surface treatment using a crossed electromagnetic field. The optimum discharge condition has been studied for the gas pressure, the magnetic flux density and the distance between substrate and electrodes. In result, contact angle is increased by surface treatment using $CF_4$ Plasma. Therefore we expect that SPM to control contact angle is applied to many industries.

• Journal of Welding and Joining
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• 제20권4호
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• pp.498-504
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• 2002

Fluxless flip chip bonding process using plasma treatment instead of flux was investigated. The effect of plasma process parameters on tin-oxide etching characteristics were estimated with Auger depth profile analysis. The die shear test was performed to evaluate the adhesion strength of the flip chip bonded after plasma treatment. The thickness of oxide layer on tin surface was reduced after Ar+H2 plasma treatment. The addition of H2 improved the oxide etching characteristics by plasma. The die shear strength of the plasma-treated Sn-Pb solder flip chip was higher than that of non-treated one but lower than that of fluxed one. The difference of the strength between plasma-treated specimen and non-treated one increased with increase in bonding temperature. The plasma-treated flip chip fractured at solder/TSM interface at low bonding temperature while the fracture occurred at solder/UBM interface at higher bonding temperature.

• 한국표면공학회지
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• 제55권6호
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• pp.308-318
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• 2022

The surface modification and treatment using thermal plasma were reviewed in academic fields. In general, thermal plasma is generated by direct current (DC) and radiofrequency (RF) power sources. Thermal spray coating, a typical commercial process using thermal plasma, is performed by DC thermal plasma, whereas other promising surface modifications have been reported and developed using RF thermal plasma. Beyond the thermal spray coating, physical and chemical surface modifications were attempted widely. Superhydrophobic surface treatment has a very high industrial demand particularly. Besides, RF thermal plasma system for large-area film surface treatment is being developed. Thermal plasma is especially suitable for the surface modification of low-dimensional nanomaterial (e.g., nanotubes) by utilizing high temperature and rapid quenching. It is able to synthesize and modify nanomaterials simultaneously in a one-pot process.

• 한국전기전자재료학회논문지
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• 제22권8호
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• pp.645-649
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• 2009

We investigated the effects of a high density $O_2$ plasma treatment on the structural and electrical properties of Ga-, B- codoped ZnO (GZOB) films. The GZOB films were deposited on polymer substrate without substrate heating by DC magnetron sputtering. Prior to the GZOB film growth, we treated a polymer substrate with highly dense inductively coupled oxygen plasma. The optical transmittance of the GZOB film, about 80 %, was maintained regardless of the plasma pre-treatment. The resistivity of the GZOB film on PC substrate decreased from 9.08 ${\times}$ $10^{-3}$ ${\Omega}-cm$ without an $O_2$ plasma pre-treatment to 2.12 ${\times}$ $10^{-3}$ ${\Omega}-cm$ with an $O_2$ plasma pre-treatment. And PES substrate decreased from 1.14 ${\times}$ $10^{-2}$ ${\Omega}-cm$ without an $O_2$ plasma pre-treatment to 6.13 ${\times}$ $10^{-3}$ ${\Omega}-cm$ with an $O_2$ plasma pre-treatment.

• 한국세라믹학회지
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• 제34권11호
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• pp.1121-1128
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• 1997

In this study, the Ar plasma treatment was used to improve the surface roughness of Poly-Si1-xGex thin film deposited by RTCVD. The surface roughness and the resistivity of Si1-xGex thin film were investigated with variation of Ar plasma treatment parameters (electrode distance, working pressure, time, substrate temperature and R.F power). When the Ar plasma treatment was used, the cluster size decreased by the surface etching effect due to the increasing surface collision energy of particles (ion, neutral atom) in plasma under the conditions of decreasing electrode distance and increasing pressure, time, temperature, and R. F power. Although the surface roughness value decreased by the reduction of the cluster size due to surface etching effect, however, the resistivity increased. This may be due to the surface damage caused by the increasing surface collision energy. It was concluded that the surface roughness could be improved by the Ar plasma treatment, while the resistivity was increased by the surface damage on the substrate.

• 한국정밀공학회지
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• 제20권8호
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• pp.153-157
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• 2003

In the present work, the effect of plasma treatment of aluminum on the fracture toughness of CFRP/aluminum composites was investigated. The surface of the aluminum was treated by a DC plasma. The plasma treatment was carried out at volume ratio of acetylene gas to nitrogen gas of 5:5 and the treatment time used was 30 sec. Cracked lap shear specimens of aluminum/CFRP composites were made using secondary bonding procedure. Fracture toughness of aluminum/CFRP composites was determined using the work factor approach. Then, the fracture toughness of plasma-treated aluminum/CFRP composites was compared with that of untreated aluminum/CFRP composites. The results showed that the fracture toughness of plasma-treated aluminum/CFRP composites was about 50 % higher than that of untreated aluminum/CFRP composites.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.232-233
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• 2005

The Surface of semi-conductive silicone rubber was treated by oxygen plasma to improve adhesion and electric performance in joints between insulating and semi-conductive silicone materials. Surface characterizations were assessed using contact angle measurement and Fourier transform infrared spectroscope (FTIR). Adhesion level was understood from T-peel tests between plasma treated semi-conductive and insulating material. Electrical breakdown strength was measured to understand the charge of electrical performance. From the results, the oxygen plasma treatment produces a significant increase in function group of containing oxygen which can be mainly ascribed to the creation of carbonyl groups on the silicone surface from the strength were improved. Therefore it is concluded then plasma treatment leads to decrease voids originating form poor adhesive, and the improve the adhesion in silicone interface. So we could obtain higher electrical design level of silicone material used for electrical apparatus using oxygen plasma treatment.

• Journal of Ginseng Research
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• 제45권4호
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• pp.519-526
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• 2021

Background: This study aimed to investigate the effect of cold plasma treatment on the improvement of seed germination and surface sterilization of ginseng seeds. Methods: Dehisced ginseng (Panax ginseng) seeds were exposed to dielectric barrier discharge (DBD) plasma operated in argon (Ar) or an argon/oxygen mixture (Ar/O₂), and the resulting germination and surface sterilization were compared with those of an untreated control group. Bacterial and fungal detection assays were performed for plasma-treated ginseng seeds after serial dilution of surface-washed suspensions. The microbial colonies (fungi and bacteria) were classified according to their phenotypical morphologies and identified by molecular analysis. Furthermore, the effect of cold plasma treatment on the in vitro antifungal activity and suppression of Cylindrocarpon destructans in 4-year-old ginseng root discs was investigated. Results: Seeds treated with plasma in Ar or Ar/O₂ exhibited a higher germination rate (%) compared with the untreated controls. Furthermore, the plasma treatment exhibited bactericidal and fungicidal effects on the seed surface, and the latter effect was stronger than the former. In addition, plasma treatment exhibited in vitro antifungal activity against C. destructans and reduced the disease severity (%) of root rot in 4-year-old ginseng root discs. The results demonstrate the stimulatory effect of plasma treatment on seed germination, surface sterilization, and root rot disease suppression in ginseng. Conclusion: The results of this study indicate that the cold plasma treatment can suppress the microbial community on the seed surface root rot in ginseng.