• Transactions on Electrical and Electronic Materials
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• v.15 no.4
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• pp.217-220
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• 2014

We studied the plating properties of Sn-Pb solder according to the shape of the Cu wire's cross-section for photovoltaic ribbon. The thickness of the Sn-Pb layer largely decreased to 29% on a curved Cu surface, compared to a flat Cu surface. This phenomenon is caused by the geometrical decrease in the contact angle of the liquid Sn-Pb solder and an increase in the surface energy of the solid/vapor on the curved Cu surface. We suggest a new ribbon's design where the Cu wire's cross-section is a semi-ellipse. These semi-ellipse ribbons can decrease the use of Sn-Pb solder to 64% and increase the photovoltaic efficiency, by reducing the contact area between the ribbon and cell, to 84%. We also see an improvement of reflectivity in the curved surface.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.20-27
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• 1998

The characteristics of the bubble adsorptive separation of CTAB(cetyltrimethylammonium bromide) and CuS precipitates was investigated. The Langmuir adsorption equation was adequate at very low concentration of CTAB, and the adsorption heat was determined from the batch analysis considering the bulk liquid accompanied between bubbles. The adsorption mechanism was explained with the collision adsorption between bubbles and precipitate particles. The optimum concentration ratio of (CTAB) to (CuS) for adsorptive separation was 0.1 and coincided with the ratio for the coagulation of particles. The collection efficiency was depended on pH and CTAB concentration but independent of the air flow rate, and the maximum efficiency was 0.0002. The selective separation of ZnS from the mixture of Cu-Cd-Zn sulfides was obtained by the bubble adsorption with CTAB.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.1
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• pp.36-43
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• 2000

The sulfur pressure and TRA(rapid thermal annealing) conditions of the fabricated SrS:CuCl TFEL devices were optimized to improve blue color luminance. The thickness of the phosphor layer of SrS:CuCl TFEL devices fabricated by electron beam deposition system was 6000 ~ 8000 ${\AA}$. The fabricated TFEL devices were annealed at 800 $^{\circ}C$ for 3 min. It was shown that the crystallinity of SrS:CuCl phosphor was improved by an increase in RTA temperature and RTA time. Blue color was emitted from the TFEL device with emission peak wavelength of 468 nm and 500 nm. The CIE color coordinates were x = 0.21, y = 0.33. The luminance($L_{40}$) of TFEL device strongly depended on the sulfur pressure of deposition chamber and increased from 262 cd/$m^2$ to 728 cd/m2 as the sulfur pressure increased from $8{\times}10^{-6}$ torr to $2{\times}10^{-5}$ torr.

• Journal of the Korean Magnetics Society
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• v.13 no.1
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• pp.15-20
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• 2003

Diffusion speed of Cu metal fine particle is fast better than CuO, so it will promote grain growth in sintering. In this paper, the influence on substituting Cu fine particle for CuO of NiCuZn ferrite with basic composition (N $i_{0.204}$C $u_{0.204}$Z $n_{0.612}$ $O_{1.02}$)F $e_{1.98}$ $O_{2.98}$ has been investigated with varying Cu/CuO ratio. The perfect spinel structure of sintered specimen at 90$0^{\circ}C$ was confirmed by the analysis of XRD patterns. The best condition was obtained when the ratio of Cu/CuO was 60%, and the permeability was 1100 and Ms was 87 emu/g in this condition. Cu has influenced on grain growth in sintering, substituting Cu fine particle for CuO could lower sintering temperature over the 3$0^{\circ}C$. After sintering, substituting Cu performed as good as CuO.s CuO.s CuO.

• Advances in materials Research
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• v.13 no.1
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• pp.55-62
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• 2024

Cu-based sulfides have recently emerged as promising thermoelectric (TE) materials due to their low cost, non-toxicity, and abundance. In this research, point defect structure of Cu_2-xZnSnS₄ (x=0.1, 0.2, 0.3) samples were synthesized by the mechanical alloying method. Mixed powders of Cu, Zn, Sn and S were milled using high energy ball milling at a rotation speed of 300 rpm in Ar atmosphere. The milled Cu_2-xZnSnS₄ powders were heat-treated at 723 K for 24 h, and subsequently consolidated using spark plasma sintering (SPS) under an applied pressure of 60 MPa for 15 min. The thermal conductivity of the sintered Cu_2-xZnSnS₄ samples was evaluated. A well-defined Cu_2-xZnSnS₄ powders were successfully formed after milling for 16 h, with the particle sizes mostly distributed in the range of 60-100 nm. The lattice constants of aand cdecreased with increasing composition value x. The thermal conductivity of sintered x=0.1 sample exhibited the lowest value and attained 0.93 W/m K at 673 K.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.169-169
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• 2000

최근 반도체 소자의 초고집적화 현상에 따라 기존의 Al-base 합금에 대한 한계에 달하면서 그에 대한 대체 물질로 Cu가 관심을 모으게 되었고 그럼으로써 Cu metallization을 위한 많은 연구가 진행되어 왔다. Cu는 Al-base 합금계보다 비저항이 낮고, 녹는점이 높으며, 또한 electromigration 특성이 뛰어난 것으로 알려져 있다. 공학적인 면에서 이미 이들 계에 대한 adhesion 및 전기적 특성에 대한 많은 연구가 있어왔지만, 이들 특성 변화에 대한 물리적 의미를 제공할 만한 기초 자료들이 부족한 상태이다. 본 연구에서는 부도체인 polyimide 박막과 diffusion barrier인 TiN 박막위에서의 Cu 박막성장에 따르는 interface chemical reaction의 변화를 XPS를 이용하여 관찰함으로서 이들 계에 있어서의 adhesion과의 관계를 조사하였다. 그리고 XPS를 이용한 modified surface accumulation method를 적용시켜 TiN diffusion barrier를 통한 Cu의 grain boundary diffusion 상수들을 측정하였다. Cu/TiN system의 경우에는 interface chemical reaction이 일어나지 않았지만 Cu/polymide system에 있어서는 boundary diffusivity는 특히 40$0^{\circ}C$에서 $650^{\circ}C$ 영역에서, Db=60$\times$10-11exp[-0.29/(kBT)]cm2/sec 이었다.

• Korean Journal of Metals and Materials
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• v.50 no.6
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• pp.419-425
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• 2012

The purpose of this research was to develop a low Ni austenitic cast iron through replacing Ni by Cu and Mn because they are cheaper than Ni. The effect of the Cu content (6-12 wt%) on the microstructure characteristics was investigated in Fe-3%C-16%(Ni+Cu+Mn) cast iron. Contrary to general effect of the Cu on cast iron, the result of the microstructure analysis indicated that bainite and cementite were formed in high Cu content (>8 wt%Cu). A crystallized Cu-solution (Cu-Mn) phase and MnS in the Cu-solution were formed. The quantity of those phases increased as the Cu content increased. Consequently, the high Cu content in the composition ratio (Ni+Cu+Mn=16%) caused the formation of Cu-Mn/MnS and those phases decreased the effect of Cu and Mn on austenite formation. For this reason, bainite and cementite were formed in high Cu content.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.3
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• pp.112-117
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• 2018

The metal alkoxide, CuCo-glycerate nanospheres (NSs), were successfully synthesized as Cu-Co bimetallic sulfides hierarchical multi-shelled hollow nanospheres ($CuCo_2S_4$ HMHNSs) through solvothermal synthesis. In this reaction mechanism, the solvothermal temperature and the amount of glycerol as a cosurfactant play significant role to optimize the morphology of CuCo-glycerate NSs. Furthermore, $CuCo_2S_4$ HMHNSs were obtained under optimized sulfurization reaction time of 10 h via anion exchange reaction between glycerate and sulfur ions. Finally, the structural and chemical compositions of CuCo-glycerate NSs and $CuCo_2S_4$ HMHNSs were confirmed through field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and electrochemical performances.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.49-56
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• 2003

An experiment was conducted to study the effects of the dietary Cu sources on the performance of the weanling pigs. Forty-eight, 24 in each sex, 4 weeks old pigs were assigned to four treatments; control, methionine-Cu chelate, chitosan-Cu chelate or yeast-Cu chelate. Control diet contained 136ppm Cu to which additional 100ppm Cu in different chelated form was added to the respective treatment. Individual pig weight and feed intake of each pen were recorded weekly for 5 weeks. Average daily feed intakes(ADFI), average daily gains(ADG) and ADFI/ADG were not significantly different among treatments. Nutrient availability was not also significantly affected by treatments. Serum triglyceride concentration of chitosan-Cu treatment was significantly lower than those of methionine-Cu and yeast-Cu treatments but was not significantly different from that of the control. Serum cholesterol concentration of yeast-Cu was significantly lower than those of the control and methionine-Cu but was not significantly different from that of chitosan-Cu treatment. Serum HDL-cholesterol concentration was not significantly affected by treatments. Serum IgG concentrations of all copper treatments were significantly lower than that of the control. It was concluded that Cu-chelates supplemented to the basal diet (136ppm Cu) by the level of 100ppm Cu did not significantly affect growth performance of weaning pigs. However, serum parameters of cholesterol, cholesterol and IgG were significantly affected by the treatments.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.288-294
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• 1993

Flue gas control systems for small-scale combustors must be designed to provide highly effective removal of three criteria pollutants (S $O_{2}$, N $O_{x}$ and particulate matter), and must be safe, reliable and small. These requirements make dry, regenerative clean-up process particularly attractive and this paper describes a new concept for integrated pollutant control : a filter comprised of layered, gas permeable membranes that act as an S $O_{2}$ sorbant, a N $O_{x}$ reduction catalyst and a particulate filter. A mixed metal oxide sorbent, Cu-Ce was used as a sorbent/catalyst and the activity was compared with Cu-7Al. The S $O_{2}$ removal eficiency of Cu-Ce was increased with temperature increase up to 500$^{\circ}$C and the catalytic activity for NO was higher than that of Cu-7Al. By the sulfation of Cu-Ce, the reduction activity was increased at the temperature higher than 350$^{\circ}$C. The regeneration of Cu-Ce was very fast and some amount of elemental sulfar was found.