• 한국표면공학회지
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• 제38권2호
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• pp.49-54
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• 2005

Flexible copper clad laminates (FCCL) fabricated by sputtering has advantages in fine pitch etching and dimensional accuracy than previous casting or laminating type FCCL, But its lower adhesion is inevitable technical challenge to solve for commercializing it. Chromium (Cr) which strongly reacts with O moiety was used as tie-coating layer in order to improve low adhesion between copper (Cu) and polyimide (PI). Sputtering raw polyimide (SRPI) and casting raw polyimide (CRPI) were used as substrates at this research. PI was pretreated by plasma before sputtering, and each sample was varied with RF power and Cr thickness on sputtering. Peel strength of the FCCL on SRPI was higher than that on CRPI. Adhesion had maximum value when 10 nm of Cr was deposited on SRPI by RF power of 50 W. It seems to be by the formation of Cu-Cr-O solid solution at the metal-PI interface.

• Korean Journal of Acupuncture
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• 제25권4호
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• pp.89-104
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• 2008

Objectives : This study was undertaken to determine the in vitro antioxidant activity of the extract of Chilgitang herb-acupuncture solution (CHAS). Methods : The radical scavenging capacity was tested by 2,2-diphenyl-1-picryl-hydrazyl (DPPH), hypoxanthine-xanthine oxidase system, DCFH-DA assay, nitric oxide and peroxynitrite generating system. In addition, antioxidant activity on copper and AAPH mediated human low-density lipoprotein (LDL) oxidation was measured by using TBARS assay and relative electrophoretic mobility assay. The amount of total phenolic compounds was assayed by the Folin-Ciocalteu method. Results : CHAS revealed a potent scavenging activity on DPPH radical(82%), superoxide anions(73%), hydroxyl radical(63%), nitric oxide (99%) and peroxynitrite (99%). Moreover, CHAS showed a strong inhibitory effect (59%) on $FeCl_2$-ascorbic acid induced lipid peroxidation of rat liver homogenate. CHAS also markedly inhibited copper(81%) and AAPH(56%)-mediated LDL oxidation, and effectively suppressed the electrophoretic mobility during exposure of human LDL to copper ions. CHAS (82 mg/g) contained higher concentration of total phenolic compounds than that of water extract (45 mg/g) obtained from Chilgitang. Conclusions : These results indicate that CHAS may protect against ROS- or RNS involved diseases, including cardiovascular diseases.

• Environmental Engineering Research
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• 제15권1호
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• pp.35-40
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• 2010

Bung Boraphet is the largest freshwater reservoir in Thailand. This study examined the accumulation of copper (Cu) and lead (Pb) in water, sediment and tissues of Asian clams (Corbicula sp.) within Bung Boraphet to assess the possible polluting effect of soil erosion and the dissolution of water soluble salts from the Nan River. Samples were collected from 12 study sites within Bung Boraphet between February and December 2008. The physicochemical parameters of the water including temperature, pH, turbidity, ammonia nitrogen, nitrate nitrogen, orthophosphates, biochemical oxygen demand, dissolved oxygen, Cu, and Pb were measured. The water in Bung Boraphet was found to be medium clean according to the surface water quality standard of Thailand. The levels of Cu and Pb in the water were low but heavy metals were detected at higher levels in the sediment and tissues of Corbicula sp. In the near future, management practices and regulator approaches for Cu and Pb contamination will be needed to protect the water in Bung Boraphet.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제2권2호
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• pp.164-168
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• 1999

Background: Wilson disease (WD) is an autosomal recessive disorder of copper transport and characterized by degenerative changes in the brain, liver dysfunction, and Kayser-Fleischer rings due to toxic accumulation of copper. Since the identification of Wilson disease gene (ATP7B), more than 80 mutations have been detected among the different ethnic groups. Methods: Twenty three children with Wilson disease were included in this study. They were all diagnosed by low serum ceruloplasmin and increased 24 hour urinary copper excretion with characteristic clinical findings. We analysed WD gene mutation by assessing the nucleotide sequence of exon 7, 8, 9 and 10 including intron-exon boundaries of ATP7B gene from genomic DNA. Results: Arg778Leu mutation was identified in 16 WD patients; three were homozygous and 13 were heterozygous for this mutation. Of the 46 alleles, 19 alleles had a Arg778Leu mutation (19/46=41%). Homozygote patients had neurologic forms of WD. Arg778Leu mutation was not found among 50 normal healthy persons. Conclusion: Arg778Leu mutation is a common mutation in Korean WD gene. Arg778Leu mutation screening might be used as a useful supplementary diagnostic test in some patients to confirm Wilson disease in Korea.

• Tribology and Lubricants
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• 제21권2호
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• pp.77-82
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• 2005

In previous paper, the wear properties of clutch facing materials with two different copper amounts against fly-wheel materials used in the clutch system were investigated by sliding wear tests at different applied loads and speeds. This paper have been aimed to evaluate the friction properties for clutch facing materials at the same test conditions as the previous paper. The experimental results indicated that the friction properties of clutch facing materials are influenced from the thermal conductivities of the clutch facing material and the counter material. The clutch facing material with the lower thermal conductivity and the fly-wheel material with the higher thermal conductivity showed the low and stable friction coefficient in the range of high sliding speed. This appears to be due to the formation of a film on the surface of the fly-wheel material.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.759-761
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• 2002

A new method for the preparation of copper activated zinc sulfide phosphors by combustion method has been proposed. Copper nitrate was decomposed with an organic fuel to give fine sized particles in presence of alkali metal halides at low temperature than the conventional synthesis. Organic compound also acted as fuel at 500 $^{\circ}C$ with rapid heating. The phosphors thus obtained were then heated at 900 $^{\circ}C$ in an inert atmosphere for 2-5 hrs to get better luminescent properties.

• 한국환경과학회지
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• 제14권7호
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• pp.669-674
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• 2005

Catalytic combustion of toluene was investigated on $CuOx/SnO_2-ZrO_2\;CuOx/SnO_2\;CuOx/ZrO_2$ catalysts prepared by impregnation. Characteristics of catalysts loaded on binary support and single support were observed by TPR, TPO, XRD, XPS techniques. The results on catalytic combustion showed that binary supports improve the activity of copper in the combustion of toluene. The reason for high catalytic activity on toluene combustion of $CuOx/SnO_2-ZrO_2$ catalyst was ascribed to oxidation$\cdot$reduction activity at low temperatures and stability of oxidation state after reduction.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.293.1-293.1
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• 2016

Various materials including conductive, dielectric, and semi-conductive materials, constitute suitable candidates for printed electronics. Metal nanoparticles (e.g. Ag, Cu, Ni, Au) are typically used in conductive ink. However, easily oxidized metals, such as Cu, must be processed at low temperatures and as such, photonic sintering has gained significant attention as a new low-temperature processing method. This method is based on the principle of selective heating of a strongly absorbent film, without light-source-induced damage to the transparent substrate. However, Cu nanoparticles used in inks are susceptible to the growth of a native copper-oxide layer on their surface. Copper-oxide-nanoparticle ink subjected to a reduction mechanism has therefore been introduced in an attempt to achieve long-term stability and reliability. In this work, a flash-light sintering process was used for the reduction of an inkjet-printed Cu(II)O thin film to a Cu film. Using a photographic lighting instrument, the intensity of the light (or intense pulse light) was controlled by the charged power (Ws). The resulting changes in the structure, as well as the optical and electrical properties of the light-irradiated Cu(II)O films, were investigated. A Cu thin film was obtained from Cu(II)O via photo-thermal reduction at 2500 Ws. More importantly, at one shot of 3000 Ws, a low sheet resistance value ($0.2527{\Omega}/sq.$) and a high resistivity (${\sim}5.05-6.32{\times}10^{-8}{\Omega}m$), which was ~3.0-3.8 times that of bulk Cu was achieved for the ~200-250-nm-thick film.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.192-193
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• 2007

An evaporated Ti/Pd/Ag contact system is most widely used to make high-efficiency silicon solar cells, however, the system is not cost effective due to expensive materials and vacuum techniques. Commercial solar cells with screen-printed contacts formed by using Ag paste suffer from a low fill factor and a high shading loss because of high contact resistance and low aspect ratio. Low-cost Ni and Cu metal contacts have been formed by using electro less plating and electroplating techniques to replace the Ti/Pd/Ag and screen-printed Ag contacts. Ni/Cu alloy is plated on a silicon substrate by electro-deposition of the alloy from an acetate electrolyte solution, and nickel-silicide formation at the interface between the silicon and the nickel enhances stability and reduces the contact resistance. It was, therefore, found that nickel-silicide was suitable for high-efficiency solar cell applications. Cu was electroplated on the Ni layer by using a light induced plating method. The Cu electroplating solution was made up of a commercially available acid sulfate bath and additives to reduce the stress of the copper layer. In this paper, we investigated low-cost Ni/Cu contact formation by electro less and electroplating for crystalline silicon solar cells.

• 마이크로전자및패키징학회지
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• 제19권2호
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• pp.67-72
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• 2012

최근에 전자 산업 분야에서 장치의 고용량을 구현 하기 위해 구동 drive IC의 선폭은 좁아지고 집적도는 증가하고 있다. 이러한 반도체, 전자 산업 분야의 초소형화, 고밀도화에 따라 FCCL(Flexible Copper Clad Laminate)의 표면 품질이 더욱 중요해 지고 있다. FCCL의 표면 결함으로는 돌기, 스크레치, 덴트 등이 있다. 특히 돌기가 표면에 존재할 경우 후속 공정에서 쇼트와 같은 불량을 유발할 수 있으며, 제품의 품질 저하를 야기 시킬 수 있다. 하지만 표면에 돌기가 존재한다 하더라도, 전해액의 레벨링 특성이 우수하다면 돌기의 성장을 막을 수 있다.평탄하고, 결함이 없는 도금표면을 얻기 위해서는 첨가제의 역할이 필수적이다. 평탄한 구리 표면을 형성하기 위해서 stock solution에 가속제, 억제제, 레벨러를 첨가하였다. 레벨러를 첨가하는 이유는 평탄한 표면을 얻고, 돌기의 형성을 억제하기 위함이다. 구리도금 표면 형상을 향상시키기 위한 레벨러로는 SO(Safranin O), MV(Methylene Violet), AB(Alcian Blue), JGB(Janus Green B), DB(Diazine Black) and PVP(Polyvinyl Pyrrolidone)가 사용되었다. 도금 첨가제와 도금 조건의 변화를 통해 도금시레벨링 특성을 향상시키고, 레벨링 특성 측정을 위해 니켈 인공돌기를 제작 한 후 레벨링 특성을 측정하였다.