• Korean Journal of Materials Research
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• v.19 no.6
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• pp.344-348
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• 2009

The electrolyte effects of the electroplating solution in Cu films grown by ElectroPlating Deposition(EPD) were investigated. The electroplated Cu films were deposited on the Cu(20 nm)/Ti (20 nm)/p-type Si(100) substrate. Potentiostatic electrodeposition was carried out using three terminal methods: 1) an Ag/AgCl reference electrode, 2) a platinum plate as a counter electrode, and 3) a seed layer as a working electrode. In this study, we changed the concentration of a plating electrolyte that was composed of $CuSO_4$, $H_2SO_4$ and HCl. The resistivity was measured with a four-point probe and the material properties were investigated by using XRD(X-ray Diffraction), an AFM(Atomic Force Microscope), a FE-SEM(Field Emission Scanning Electron Microscope) and an XPS(X-ray Photoelectron Spectroscopy). From the results, we concluded that the increase of the concentration of electrolytes led to the increase of the film density and the decrease of the electrical resistivity of the electroplated Cu film.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.11-17
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• 2020

Copper has been proved to be the best catalyst for electrochemical CO2 reduction reaction, however, for optimal efficiency and selectivity, its performance requires improvements. Electrochemical CO2 reduction reaction (RR) using CuO nanowire electrode was performed with different concentrations of KHCO3 electrolyte (0.1 M, 0.5 M, and 1 M). Cu(OH)2 was formed on Cu foil, followed by thermal-treatment at 200℃ under the air atmosphere for 2 hrs to transform it to the crystalline phase of CuO. We evaluated the effects of different KHCO3 electrolyte concentrations on electrochemical CO2 reduction reaction (RR) using the CuO nanowire electrode. At a constant current (5mA), low concentrated bicarbonate exhibited a more negative potential -0.77 V vs. Reversible Hydrogen Electrode (RHE) (briefly abbreviated as VRHE), while the negative potential reduced to -0.33 VRHE in the high concentration of bicarbonate solution. Production of H2 and CH4 increased with an increased concentration of electrolyte (KHCO3). CH4 production efficiency was high at low negative potential whereas HCOOH was not influenced by bicarbonate concentration. Our study provides insights into efficient, economically viable, and sustainable methods of mitigating the harmful environmental effects of CO2 emission.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.73-76
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• 2021

This thesis described the optical and electrical properties of the alternating current powder electroluminescent device based on Ag nanowire as a transparent electrode. The Ag nanowire electrode showed the morphology of 20 nm in diameter and 15 ㎛ in length. The transparent electroluminescent devices that were fabricated using the nanomilled ZnS : Cu, Mn phosphor by bar-coating process showed the transmittance of 67%. In order to improve the luminous efficiency, it is necessary to apply the transparent dielectric layer and increase the amount of the nanophosphor while maintaining the transmittance.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.3
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• pp.429-436
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• 2003

The electrical discharge machining(EDM) with Si electrode instead of Gr or Cu electrode. made enormous effects on the surface. machining time, anti-caustic workpiece surface and so on In this paper. we experimented on the inter-role distance during discharge the electrical phenomenon of inter-pole, the distribution of discharge point. the distribution of off load time. etc., using Si electrode Cu electrode and Gr electrode under the same machining condition. As a result of a large quantity generated exclusive powders. the performance of the EDM using Si electrode. compared with EDM using others. is improved. We show that the quantities of those make far pole-gap discharge and discharge scatter under stable machining status possible.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.279-280
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• 2009

Organic field-effect transistors (OFETs) are of interest for use in widely area electronic applications. We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different metal electrode. The CuPc FET device was made a top-contact type and the substrate temperature was room temperature. The source and drain electrodes were used an Au and Al materials. The CuPc thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed a typical current-voltage (I-V) characteristics in CuPc FET with different electrode materials.

• Journal of Powder Materials
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• v.10 no.5
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• pp.337-343
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• 2003

Nanostructured Cu-$Al_2O_3$ composite powders were synthesized by thermochemical process. The synthesis procedures are 1) preparation of precursor powder by spray drying of solution made from water-soluble copper and aluminum nitrates, 2) air heat treatments to evaporate volatile components in the precursor powder and synthesis of nano-structured CuO + $Al_2O_3$, and 3) CuO reduction by hydrogen into pure Cu. The suggested procedures stimulated the formation of the gamma-$Al_2O_3$, and different alumina formation behaviors appeared with various heat treating temperatures. The mean particle size of the final Cu/$Al_2O_3$ composite powders produced was 20 nm, and the electrical conductivity and hardness in the hot-extruded bulk were competitive with Cu/$Al_2O_3$ composite by the conventional internal oxidation process.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.761-762
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• 2006

W-Cu alloy was very useful material for a heat sink, high electric contact and EDM electrode. Powder injection molding (PIM) is the optimum manufacturing technology to provide W-Cu components with low-cost and high-volume. We used various compositions of tungsten coated copper powders (W-Cu with 10 to 80 wt-% of copper) to manufacture W-Cu components by PIM. The optimum mixing, injection molding, debinding and sintering conditions to provide the high performance W-Cu components were investigated. The thermal and mechanical properties of W-Cu parts by PIM were measured. Finally, we can verify the high performance of W-Cu components by PIM with the tungsten coated copper.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.728-734
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• 1996

To obtain the relation in the electrochemical reduction of $CO_2$ in aqueous $KHCO_3$ colution between an activity for the product and the nature of Cu electrode, the electrode surface was characterized by using two methods: X-ray photoelectron spectroscopy (XPS) and photoelectron emission (PE) measurement. Electrolyses were performed with Cu electrodes pretreated in several ways. The distribution of the products changed drastically with electrolysis time and the pretreatment method. The features in XPS spectra were closely connected with the product distribution. The oxide film at the electrode surface was gradually reduced to bare Cu metal with electrolysis time, resulting in a variation of the product distribution. PE was measured by verying the wavelength of incident light at several temperatures. The dependence of PE on the measurement temperature changed greatly before and after electrolysis.

• Macromolecular Research
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• v.9 no.3
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• pp.179-183
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• 2001

Cathode materials for the polymer electrolyte membrane fuel cell was prepared by electropoly-merization of aniline at carbon paper in the presence of copper tetrasulfonato-phthalocyanine (CuTsPc) and their electrocatalytic behavior was studied. The amount of polyaniline and CuTsPc in the carbon paper was determined by UV spectroscopy of residual solution in electrochemical cell. The redox process of the prepared electrodes was investigated with cyclic voltammetry. The highest reversible current density was observed at the electrode that contains 27.6 wt% of polyaniline and 19.7 wt% of CuTsPc. The morphology of composite electrode from SEM showed the presence of large cluster of polyaniline with CuTsPc, which should be more finely interpenetrated into macropores of carbon for the better electrocatalytic activity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1259-1264
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• 2010

This paper was researched about effectiveness of the electrochemical cell which is composed of the sea water and the Cu/Zn electrode. The electric potential difference between copper and zinc finally reached 0.51 volts. Short current decreased with time. It might depend on the electromotive force decreasing. Confirmed the load resistance and electrode affect in electromotive force and electric current. The resistance which shows a maximum output power was 20[$\Omega$], and the maximum output power from this resistance was evaluated as 0.736mW. In order to calculate the energy which creates from electrochemical cell, charging voltage of the capacitor with various capacitance was investigated. It was found that energy harvesting possibility of the cell which is made of a sea water electrolyte and the copper/the zinc.