• 응용통계연구
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• 제27권4호
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• pp.543-552
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• 2014

최근 휴대단말기 시장에서는 블루투스, GPRS, EDGE, 3GSM, HSDPA 등과 같은 높은 대역폭의 RF를 사용하고 있다. 높은 대역폭의 RF 영역에서는 높은 면저항(Sheet resistance)을 갖는 무전도 금속박막 코팅 방법이 사용되고 있는데, 기존의 무전도 금속증착은 사출물 세정, UV 하도 코팅, 금속증착, UV 중도 코팅, 상도 코팅 등 다수의 복합 공정으로 이루어져 있다. 특히 하도공정은 금속 증착(Sputtering)과 일괄 처리가 어려워 생산성이 낮고 생산원가 상승의 원인이기도 하다. 따라서 이를 극복하기 위하여 최근 Na 등 (2014)은 무전도 금속코팅에서 Primer 대체를 위한 전자빔의 표면처리의 가능성을 가능함을 보였다. In this paper, 플라즈마 생성 전자빔 소스(Plasma generated electron beam source)를 활용하여 PC/ABS 수지 사출물의 공정을 실험계획법에 의한 전자빔 조사 조건을 탐색하여, 즉, 수지 표면처리공정 조건을 탐색하여, 그 실험 결과를 분석하여, 진공전처리공정 개발 및 양산공정라인의 처리의 최적 조건을 찾고자 한다.

• 한국환경보건학회지
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• 제38권3호
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• pp.251-260
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• 2012

Objectives: The purpose of this study was evaluating the applicability of the circulation dielectric barrier plasma process (DBD) for efficiently treating non-biodegradable wastewater, such as phenol. Methods: The DBD plasma reactor system in this study consisted of a plasma reactor (discharge, ground electrode and quartz dielectric tube, external tube), high voltage source, air supply and reservoir. Effects of the operating parameters on the degradation of phenol and $UV_{254}$ absorbance such as first voltage (60-180 V), oxygen supply rate (0.5-3 l/min), liquid circulation rate (1.5-7 l/min), pH (3.02-11.06) and initial phenol concentration (12.5-100 mg/l) were investigated. Results: Experimental results showed that optimum first voltage, oxygen supply rate, and liquid circulation rate on phenol degradation were 160 V, 1 l/min, and 4.5 l/min, respectively. The removal efficiency of phenol increased with the increase in the initial pH of the phenol solution. To obtain a removal efficiency of phenol and COD of phenol of over 97% (initial phenol concentration, 50.0 mg/l), 15 min and 180 minutes was needed, respectively. Conclusions: It was considered that the absorbance of $UV_{254}$ for phenol degradation can be used as an indirect indicator of change in non-biodegradable organic compounds. Mineralization of the phenol solution may take a relatively longer time than that required for phenol degradation.

• 청정기술
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• 제5권1호
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• pp.62-77
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• 1999

전자 및 컴퓨터 산업의 발전으로 반도체 산업은 비약적으로 발전하고 있다. 그러나 반도체 제조 공정에서 필수적으로 사용되는 각종 환경 오염 물질에 대한 규제가 세계적으로 강화되고 있어 반도체 업계의 적극적인 환경 대응책이 없이는 반도체 수출에 대한 선진국의 제재를 피하기 어렵다. 따라서 본 연구에서는 청정 기술 측면에서, 반도체 산업의 환경영향 개선을 위한 세정 공정의 기술적 대체 방안에 대하여 조사하였다. 세정 공정의 대안으로서 기상 세정 공정, UV 사용 공정, 플라즈마 사용 공정을 조사하였으며, 각 공정의 장단점을 비교하였다.

• 한국전기전자재료학회논문지
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• 제28권5호
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• pp.300-305
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• 2015

$WO_3$, $SiO_2$, and $TiO_2$ films with hydrophilic property are deposited by rf-magnetron sputtering. Their wettability is strongly depends on the presence or absence of the oxygen plasma etching on the glass substrates. The $TiO_2$ film of 50 nm-thick on the plasma etched glass shows a water contact angle (WCA) below $5^{\circ}$ which means a super-hydrophilic surface. However, WCA values are gradually degraded when the films are exposed under atmosphere, especially $WO_3$. In order to improve hydrophilic property, the degraded films can be again recovered by UV illumination for 10 sec using UV-light and the $TiO_2$ film shows a super-hydrophilic surface about $3^{\circ}$.

• 한국결정성장학회지
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• 제29권3호
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• pp.123-131
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• 2019

본 연구에서는 $TiO_{2-x}$ 산화물 박막공정을 이용한 유해 자외선차단 투명 유연 소재를 개발하고자한다. 자외선 차단 특성: 자외선 파장대의 315 nm 차단율이 95 % 이상이면서, 자외선차단특성을 갖으면서 투명성을 높인 가시광선 투과율 78 % 이상(550 nm에서 전광투과율)의 시료를 만드는 공정기술을 개발하고자 하였다. 본 연구 결과로 고성능 자외선차단 박막의 유연 소자 공정조건을 확립하고, 이질성 특성의 투명 유연 소자의 혼합형 설계와 시장 요구에 다양하게 대응이 가능한 복합 증착 기술 정립, 롤투롤(roll-to-roll) 연속 공정의 실현 및 장비, 공정 국산화 기술 확립으로써 관련 산업으로의 기술 파급 효과가 클 것으로 사료된다.

• 한국표면공학회지
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• 제54권6호
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• pp.340-347
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• 2021

Among various metal oxide semiconductors, ZnO has an excellent electrical, optical properties with a wide bandgap of 3.3 eV. It can be applied as a photocatalytic material due to its high absorption rate along with physical and chemical stability to UV light. In addition, it is important to control the morphology of ZnO because the size and shape of the ZnO make difference in physical properties. In this paper, we demonstrate synthesis of size-controlled ZnO tetrapods using an atmospheric pressure plasma system. A micro-sized Zn spherical powder was continuously introduced in the plume of the atmospheric plasma jet ignited with mixture of oxygen and nitrogen. The effect of plasma power and collection sites on ZnO nanostructure was investigated. After the plasma discharge for 10 min, the produced materials deposited inside the 60-cm-long quartz tube were obtained with respect to the distance from the plume. According to the SEM analysis, all the synthesized nanoparticles were found to be ZnO tetrapods ranging from 100 to 600-nm-diameter depending on both applied power and collection site. The photocatalytic efficiency was evaluated by color change of methylene blue solution using UV-Vis spectroscopy. The photocatalytic activity increased with the increase of (101) and (100) plane in ZnO tetrapods, which is caused by enhanced chemical effects of plasma process.

• 접착 및 계면
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• 제4권2호
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• pp.10-20
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• 2003

This paper is relative to the electroless deposition of nickel or copper films on polyimide and polytetrafluoroethylene substrates. First, it is presented an original approach of the electroless process which consists in grafting nitrogenated functionalities on the polymer surfaces via plasma or VUV-assisted treatments operating in a nitrogen-based atmosphere ($NH_3$, $N_2$), and then in catalysing the grafted surfaces in an aqueous tin-free, Pd(+2)-based solution. Adhesion of the Pd(+2) catalytic species on polymer surfaces is explained by the formation of strong covalent bonds between these species and the grafted nitrogenated groups. Second, it is show how a fragmentation test performed in conjunction with electrical measurements can be used to characterize the practical adhesion of the electroless coatings deposited on flexible polymer substrates, and to evidence the influence of some experimental parameters (plasma treatment time and nature of the gas phase).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.105-105
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• 2012

We have developed a photoemission-assisted plasma-enhanced chemical vapor deposition (PAPE-CVD) [1,2], in which photoelectrons emitting from the substrate surface irradiated with UV light ($h{\nu}$=7.2 eV) from a Xe excimer lamp are utilized as a trigger for generating DC discharge plasma as depicted in Fig. 1. As a result, photoemission-assisted plasma can appear just above the substrate surface with a limited interval between the substrate and the electrode (~10 mm), enabling us to suppress effectively the unintended deposition of soot on the chamber walls, to increase the deposition rate, and to decrease drastically the electric power consumption. In case of the deposition of DLC gate insulator films for the top-gate graphene channel FET, plasma discharge power is reduced down to as low as 0.01W, giving rise to decrease significantly the plasma-induced damage on the graphene channel [3]. In addition, DLC thickness can be precisely controlled in an atomic scale and dielectric constant is also changed from low ${\kappa}$ for the passivation layer to high ${\kappa}$ for the gate insulator. On the other hand, negative electron affinity (NEA) of a hydrogen-terminated diamond surface is attractive and of practical importance for PAPECVD, because the diamond surface under PAPE-CVD with H2-diluted (about 1%) CH4 gas is exposed to a lot of hydrogen radicals and therefore can perform as a high-efficiency electron emitter due to NEA. In fact, we observed a large change of discharge current between with and without hydrogen termination. It is noted that photoelectrons are emitted from the SiO2 (350 nm)/Si interface with 7.2-eV UV light, making it possible to grow few-layer graphene on the thick SiO2 surface with no transition layer of amorphous carbon by means of PAPE-CVD without any metal catalyst.

• 한국진공학회지
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• 제22권6호
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• pp.291-297
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• 2013

Au 촉매를 코팅한 사파이어 기판 상에서 산화아연과 흑연 분말을 혼합한 분말재료를 이용하여 VLS (vapor-liquid-solid) 법으로 산화아연 반도체 나노선을 합성하였다. 제조된 산화아연 나노선은 380 nm에서 근 자외선 영역의 NBE (near-band edge) 발광과 600 nm 부근의 가시광선 영역에서 넓게 퍼져 발광하는 상대적으로 강한 DL (deep level) 발광이 확인되었다($I_{NBE}/I_{DL}$ <1). 산화아연 나노선을 효율적인 단일 파장 자외선 발광체에 적용될 수 있도록 NBE 발광을 극대화함과 동시에 DL 발광을 억제시키기 위하여 본 실험에서는 합성된 산화아연 나노선에 수소 플라즈마 처리를 하였다. 플라즈마 처리시간이 길어짐에 따라(120초 이상) 발광특성의 향상정도는 점차로 감소하였지만, 수소 플라즈마 처리를 통해 나노선 내부에 존재하는 불순물 제어 등으로 다소 짧은 시간의 플라즈마 처리로(90초 이내) DL발광대비 NBE발광의 세기가 약 4배로 향상됨을 확인 하였다($I_{NBE}/I_{DL}$ ~4).

• 한국염색가공학회지
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• 제17권1호
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• pp.7-13
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• 2005

Continuous and intense UV irradiation on PTT film using two types of UV bulbs at different irradiation power level was carried out to modify surface characteristics of the film including zeta potential, wettability, surface energy, and dyeability. ESCA analysis of the irradiated film showed higher O/C ratio than the untreated film indicating photooxidation of outer surface layer. ATR analysis showed that the ester bonds were broken and some new groups were produced such as carboxylic acid, phenolic hydroxy, and other esters, implying that ester bonds of PTT was responsible for the observed photooxidation effect. The surface of the treated PTT film became more hydrophilic and wettable to water, coupled with increased surface energy. Polar component of the surface energy increased and nonpolar component decreased with increasing irradiation energy. The treatment also decreased zeta potential of the modified surface and nanoscale roughness increased with increasing irradiation. The dyeability of the treated films to catonic dyes was significantly improved by electrostatic and polar interaction between dye molecules and the anionic film surface. The UV irradiation seems to be a viable polymer surface modification technology, which has advantages such as no vacuum requirement and continuous process unlike plasma treatment.