• Journal of the Korean institute of surface engineering
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• v.35 no.1
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• pp.11-16
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• 2002

As environmental concerns increasing, the electronics industry is focusing more attention on lead free solder alternatives. In this research, we have researched wettability of intermediate solder of Sn3Ag9Bi5In, which include In and Bi and has similar melting temperature to Sn37Pb eutectic solder. We investigated the wetting property of Sn3Ag9Bi5In. To estimate wettability of Sn3Ag9Bi5In solder on various substrates, the wettability of Sn3Ag9Bi5In solder on high-pure Cu-coupon was measured. Cu-coupon that plated Sn, Ni and Au/Ni and Si-wafer adsorbed Ni/Cu under bump metallurgy on one side. As a result, the wetting property of Sn3Ag9Bi5In solder is a little better than that of Sn37Pb and Sn3.5Ag.

• Journal of the Korean institute of surface engineering
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• v.28 no.1
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• pp.3-13
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• 1995

Electroless Ni and Cu platings were conducted on $B_4C$ and SiC. In the electroless Ni plating, the deposition rate on $B_4C$ was higher than on SiC. However, the electroless Cu deposition occured with high deposition rate regardless of the carbide substrates used in this study. Uniformity of the deposits was better in the electroless Cu deposition than in the electroless Ni deposition. In the topographies of the electroless depositions, Ni deposits have grown as colony, whereas Cu deposits have grown as fine individual grains.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1193-1196
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• 2009

Low resistivity interconnection and high-mobility channel are required to realize ultrahigh-definition LCDs such as 4k ${\times}$ 2k TVs. We evaluated fully Cu-based gate and Source/Drain interconnections, consisting of stacked pure-Cu/Cu-Mn layers for TFT-LCDs, and found the underlying Cu-Mn alloy film has superior adhesion to glass substrates and CVD-SiOx films. It was also confirmed that wet etching of the Cu/Cu-Mn films without residues and low contact resistance with both channel IGZO and pixel ITO films can be obtained. It is thus considered that the stacked Cu/Cu-Mn structure is one of candidates to replacing conventionally pure-Cu/refractory metal.

• Advances in nano research
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• v.9 no.2
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• pp.113-122
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• 2020

Surface-Enhanced Raman Scattering (SERS) spectroscopy is a multifaceted surface sensitive methodology which exploits spectroscopy-based analysis for various applications. This technique is based on the massive amplification of Raman signals which were feeble previously in order to use them for appropriate identification at qualitative and quantitative in chemical as well as biological systems. This novel powerful technique can be utilized to identify pathogens such as bacteria and viruses. As far as SERS is concerned, one of the most studied problems has been functionalization of SERS active substrate. Metal colloids and nanostructures or microstructures synthesized using noble metals such as Au, Ag and Cu are considered to be SERS active. Silver and gold are extensively used as SERS active substrates due to chemical inertness and stability in air compare to copper. However, use of Cu as a suitable alternative has been taken into account as it is cheap. Herein, we have synthesized air-stable copper microstructures/nanostructures by chemical, electrochemical and microwave-assisted methods. In this paper, we have also discussed the use of as synthesized copper micro/nanostructures as inexpensive yet effective SERS active substrates for the fast identification of micro-organisms like Staphylococcus aureus and Escherichia coli.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.1
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• pp.21-25
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• 2015

Bending fatigue characteristics of Cu films and $8{\mu}m$ width Cu interconnects on flexible substrates were investigated, and fatigue reliability improvement was achieved through Mo-Ti alloy adhesion layer. Tensile bending fatigue reliability of Cu interconnects is 3 times lower than that of Cu films, and even compressive bending fatigue reliability of Cu interconnects is 6 times lower than that of Cu films. From these results, mechanical crack formation could be fatal in Cu interconnects. With Mo-Ti adhesion layer, fatigue reliability of Cu films and interconnects were enhanced due to the increase of adhesion strength and the suppression of slip induced crack initiation.

• 한국초전도학회:학술대회논문집
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• v.16
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• pp.89-89
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• 2006

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.05a
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• pp.58-58
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• 2003

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.13-16
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• 2000

(PbS)$_{1-x}$ -(CuS)$_{x}$ thin films(x=0, 0.5, 1) were grown on glass substrates by using a chemical bath deposition method. The molecular ratio of Pb to Cu for the PbS-CuS thin films(x=0.5) was measured about 7:3 by using EDX and XRF. The resistivity of non-annealed (PbS)$_{1-x}$ -(CuS)$_{x}$ thin films was about 10 $\Omega$ . cm. However, after annealing, the resistivity of PbS showed a little change, while PbS-CuS and CuS significantly decreased in the range of 0.002 to 0.005$\Omega$.cm. PbS was p-type and CuS was n-type.-type.

• Mycobiology
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• v.37 no.2
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• pp.109-113
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• 2009

The mineral contents of the cultivation substrates, fruiting bodies of the mushrooms, and the postharvest cultivation substrates were determined in cultivated edible mushrooms Pleurotus eryngii, Flammulina velutipes, and Hypsizigus marmoreus. The major mineral elements both in the cultivation substrates and in the fruiting bodies were K, Mg, Ca, and Na. Potassium was particularly abundant ranging 10${\sim}$13 g/kg in the cultivation substrates and 26${\sim}$30 g/kg in the fruiting bodies. On the contrary, the calcium content in the fruiting bodies was very low despite high concentrations in the cultivation substrates, indicating Ca in the cultivation substrates is in a less bio-available form or the mushrooms do not have efficient Ca uptake channels. Among the minor mineral elements determined in this experiment, Cu, Zn, and Ni showed high percentage of transfer from the cultivation substrates to the fruiting bodies. It is noteworthy that the mineral contents in the postharvest cultivation substrates were not changed significantly which implies that the spent cultivation substrates are nutritionally intact in terms of mineral contents and thus can be recycled as mineral sources and animal feeds.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.173-180
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• 1999

Thermally evaporated ZnTe films were investigated as a back contact material for CdS/CdTe solar cells. Two deposition methods, coevaporation and double-layer methods, were used for Cu doping in ZnTe films. ZnTe layers (0.2$\mu\textrm{m}$ thick) were deposited either on glass or on CdS/CdTe substrates without intentional heating of the substrates. Post-deposition annealing was performed at 200,300 and $400^{\circ}C$ for 3,6 and 9 minutes, respectively. Band gap of 2.2eV was measured for both undoped and doped films and a slight change in the shape of absorption spectra was observed in Cu-doped samples after annealing at $400^{\circ}C$. The resistivity of as-deposited ZnTe decreased from 10\ulcorner~10\ulcornerΩcm down to 10\ulcornerΩcm as Cu concentration increased from 0 to 14 at.%. There was not a noticeable change in less of annealing temperature up to $300^{\circ}C$ whereas films annealed at $400^{\circ}C$ revealed hexagonal (101) orientations as well. Some of Cu-doped ZnTe revealed x-ray diffraction (XRD) peaks related with Cu\ulcornerTe(x=1.75~2). Grain growth was observed from about 20nm in as-deposited films to 50nm after annealing at $400^{\circ}C$ by scanning electron microscopy (SEM). Cu distribution in ZnTe films was not uniform according to Auger electron spectroscopy (AES) measurements.