• Progress in Superconductivity and Cryogenics
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• v.5 no.3
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• pp.20-22
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• 2003

Y$_2$O$_3$ films were pulsed laser deposited on cube textured Ni and Ni-W substrates to be used as a single buffer layer of YBCO coated conductor. Initial deposition of $Y_2$O$_3$ films was performed in a reducing atmosphere, and subsequent deposition was done in the base pressure of the chamber and oxygen atmosphere. The $Y_2$O$_3$ films have a strong cube texture (The full width at half maximum of the ø-scan of $Y_2$O$_3$ was 8.4 which was the same as that of metal substrate) and smooth crack-free microstructure. The biaxially textured YBCO films (The full width at half maximum of the ø-scan was 10.2) pulsed laser deposited on the $Y_2$O$_3$/metal exhibited Tc(R=0) of 86.5K and Jc of 0.7 MA/cm2 at 77K in self field, representing that the $Y_2$O$_3$ single buffer layer is an efficient diffusion barrier of Ni and thus very promising for the achievement of high-Jc YBCO coated conductor.

• Journal of Powder Materials
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• v.25 no.2
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• pp.165-169
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• 2018

Rare earth elements (REEs) are considered to be vital to modern industry due to their important roles in applications such as permanent magnets, automobile production, displays, and many more. The imbalance between demand and supply of REEs can be solved by recycling processes. Regarding the needs of industry and society, the International Organization for Standardization, Technical Committee 298 (ISO/TC298) Rare Earths has been recently launched for developing international standards on rare earth elements. In accordance with the suggestion of its constituents, it is tentatively working to develop the appropriate standards under five working groups (WG) on terms and definitions (WG1), element recycling (WG2), environmental stewardship (WG3), packaging, labelling, marking, transport, and storage (WG4), and testing analysis (WG5). The scope and structure of ISO/TC298 on the topic of rare earths is discussed in this document.

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.81-81
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• 2002

• Progress in Superconductivity and Cryogenics
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• v.12 no.2
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• pp.9-12
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• 2010

A lamination system using reflow soldering was developed to enhance the mechanical properties of high temperature superconductor (HTS) tape. The laminated coated conductor tape was fabricated using the continuous lamination process. The mean, maximum, and minimum tensile loads in a T-peel test of the laminated coated conductor were 9.9 N, 12.5 N, and 7.6 N, respectively. The critical current ($I_c$) distributions of the non-laminated and laminated coated conductor were compared using anon-contact Hall probe method. The transport $I_c$ nearly matched the non-contact $I_c$; however, some degraded Ic regions were found on the length of 800 cm of laminated coated conductor. We confirmed that the cause of the partially degraded $I_c$ was due to an increase in line tension by (1) solidification induced by a change of composition that usually occurs in molten brass (Cu, Zn) in solder, or (2) non-homogeneity of the thickness of the coated conductor or metal tapes. We suggest that reflow soldering is a promising method for reinforced HTS tape if the controlling solder thickness and lamination guide are modified.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1718-1720
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• 2001

The route of surge arrester connection is very important because bends and kinds of leads increase the impedance to lightning surges and tend to nullify the effectiveness of a grounding electrode conductor. There is a need to know how effective installation of lightning surge arresters is made in order to control voltage and to absorb energy at high lightning currents. The effectiveness of a grounding conductor and bonding for 18[kV] metal oxide distribution line arresters was experimentally investigated with lightning and oscillating impulse voltages.

• Progress in Superconductivity
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• v.3 no.1
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• pp.125-129
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• 2001

NiO buffer layers were deposited on texture Ni tapes fur YBCO coated conductors by MOCVD(metal organic chemical vapor deposition) method, using a single solution source. Variables were deposition temperature and flow rate of $0_2$carrier gas. At higher temperatures, The NiO(111) texture was well developed, but the NiO(200) texture was developed at low temperatures. The best result was obtained at the deposition temperature of$ 470^{\circ}C$ and the gas flow rate of 200 sccm. FWHM value of $\omega$-scan fur NiO(200) of the film and $\Phi$-scan for NiO(111) of the film was $4.2^{\circ}$ and $7^{\circ}$, respectively.

• Journal of the Korean Electrochemical Society
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• v.21 no.2
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• pp.21-27
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• 2018

In this review, recent researches on ion transport phenomena in organic metal halide perovskite materials, which have been popular all over the world, are summarized. Although different results have been reported depending on the perovskite material composition and applied voltage, iodide seems to migrate under actual solar cell operating conditions, and occasionally methylammonium migration is observed. Perovskite is a so-called mixed conductor in which electrons and ions move simultaneously at room temperature, which greatly influences the hysteresis of the perovskite solar cell current-voltage curve and the performance degradation due to long-term operation.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.11a
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• pp.159-163
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• 2002

So far, many kinds of researches on the chip components and MCM-C RF module especially on the 3-dimensional ceramic module using embedded passives have been performed. LTCC system has many kinds of advantages, like low loss, low cost of process, stability of process etc..The electrical behaviors of components are affected by that of the material systems including dielectrics and conductors. In this study, many kinds of conductor pastes in the variation with metal content and grain size are fabricated and their effect on the characteristics of stripline resonator are examined upto 6 ㎓.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.193-198
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• 1991

Thick film copper conductors are of considerable interest in thick film industries because of both the potential cost saving compared to the noble metal conductors and the favorable properties in electrical conductivity, solderability, solder leach resistance and wire bondability, However, formation of the excellent copper thick film is a lot complicated due to easily oxidizing property of copper at high temperature. In order to get favorable thick film copper conductor, hybrid microcircuit industry utilizes majorly three kinds of firing atmosphere, such as nitrogen atmosphere, reactive atmosphere and air atmosphere. The processes and the three atmospheres for firing thick film copper conductor were extensively reviewed in this article.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.1076-1079
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• 2001

An anolmalous magnetoresistance effect has been theoretically studied at very low temperatures for composite normal metal conductors. This anomalous behavior is due to transverse Hall currents in the composite which would result in increased losses and higher effective resistance for the composite conductor. In this paper, transverse current flow and effective resistance with Cu-Al conductor configuration were analyzed using FEM(finite element method) for predicting the Hall losses to be resulted in anomalous magnetoresistance effect. And they are plotted three dimensionally to be visualized.