• Bulletin of the Korean Chemical Society
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• v.15 no.1
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• pp.20-22
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• 1994

The preparation of $YBa_2Cu_4O_8$ thick film on Ag substrate by electrophoretic deposition was directly studied. Electrophoretic deposition was carried out in solution, which was composed of presintered $YBa_2Cu_4O_8$ powder, sodium, and 2-propanol as a solvent. The deposited thick films were heat-treated in $O_2$ at 815$^{\circ}$C for 12 hours and at 450$^{\circ}$C for 12 hours. We succeeded in obtaining superconducting $YBa_2Cu_4O_8$ films on Ag substrate. Even though the chemical reactions at the $YBa_2Cu_4O_8$/Ag interface occurred in the range of 10 ${\mu}$m, superconductivity was not depressed. The thickness of the films was in the range of 60-80 ${\mu}$ m. The characteristics of the films were examined by electric resistance measurements, X-ray diffraction, and SEM observations.

• Journal of the Speleological Society of Korea
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• no.76
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• pp.15-17
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• 2006

[ $YBa_2Cu_3O_{7-{\delta}}$ ] superconductor films have been prepared on silver substrates by electrophoretic deposition. As silver does not react with $YBa_2Cu_3O_{7-{\delta}}$ compound and has little influence on its superconductivity, it is usually doped in $YBa_2Cu_3O_7$ to improve the strength of the material and eliminate micro cracks. It has been proved that Ag additive can lower the melting temperature of $YBa_2Cu_3O_{7-{\delta}}$ and act as linking bridge among $YBa_2Cu_3O_{7-{\delta}}$ particles, thus in this paper Ag doped $YBa_2Cu_3O_{7-{\delta}}$ thick films are prepared by electrophoretic co deposition. As there are only some referenced experience formula and models for co electrophoretic deposition and does not exist unified explanation, the behavior of Ag particles during co electrophoretic deposition is also studied.

• Journal of the Korean Ceramic Society
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• v.31 no.12
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• pp.1483-1490
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• 1994

YBa2Cu3Ox-Ag(YBCO-Ag) thick films were fabricated on the zirconia substrate by a screen printing method. The starting powder was a mixture of YBCO, prepared by a coprecipitation in oxalic acid, and Ag2O. The influence of heat treatment conditions on properties of thick films was investigated. It was observed that Jc of thick films was directly proportional to the orientation factor of thick films and the optimimum preparation condition was the heat treatment of thick films at 100$0^{\circ}C$ for 3 min in O2. The improvement of Jc by the addition of Ag was considered as a result of the suppression of microcracks in the films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.260-261
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• 2005

$YBa_2Cu_3O_{7-\delta}$ superconductor films have been prepared on silver substrates by electrophoretic deposition. As silver does not react with $YBa_2Cu_3O_{7-\delta}$ compound and has little influence on its superconductivity, it is usually doped in $YBa_2Cu_3O_7$ to improve the strength of the material and eliminate micro-cracks. It has been proved that Ag additive can lower the melting temperature of $YBa_2Cu_3O_{7-\delta}$ and act as linking bridge among $YBa_2Cu_3O_{7-\delta}$ particles, thus in this paper Ag doped $YBa_2Cu_3O_{7-\delta}$ thick films are prepared by electrophoretic co-deposition. As there are only some referenced experience formula and models for co-electrophoretic deposition and does not exist unified explanation, the behavior of Ag particles during co-electrophoretic deposition is also studied.

• 한국초전도학회:학술대회논문집
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• v.11
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• pp.47-47
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• 2001

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.263-266
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• 2003

The fine $YBa_2Cu_3O_x$ powder ($0.2{\sim}1.0\;{\mu}m$) is produced by sol-gel method, and electrophoresis deposition is used for the preparation of $YBa_2Cu_3O_x$ thick films which are deposited on Ag wire. The oriented $YBa_2Cu_3O_x$ was tried to be prepared by the zone-melting method under low oxygen partial pressure. The orientation and the phase composition were examined by the X-ray diffraction and the superconductivities were measured by 4 line method. The critical current densities are still quite low, which may be due to unsuitable technical parameters for zone-melting of $YBa_2Cu_3O_x$ thick films. Therefore the heat treatment condition and controlling of low oxygen partial pressure should be improved in the future experiment.

• Journal of the Speleological Society of Korea
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• no.76
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• pp.49-55
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• 2006

The submicron $YBa_2Cu_3O_x$ powder was prepared by the sol-gel method. The particle size is distributed from 0.2 to 1.0 ${\mu}m$, which benefits to eliminate the micro-cracks formed in the $YBa_2Cu_3O_x$ films deposited by electrophoresis. The powder was single phase of $YBa_2Cu_3O_x$ examined by X-ray diffraction. In the sol-gel process the citrate gel was formed from citric acid and nitrate solution of $Y_2O_3$, $Ba(NO_3)_2$ and CuO. When pH values were adjusted to 6.4-6.7, $Ba(NO_3)_2$ could be dissolved in the citrate solution completely. Appropriate evaporative temperature of the sol-gel formation is discussed. Acetone is used as electrophoreticsolution, in which some water and iodine (0.2 g/1) and polyethylene glycol (2 vol. %) are added. The concentrations of $YBa_2Cu_3O_x$ powders is 20g/l. The thickness of deposited film could be more than 50 ${\mu}m$ in 3 minutes of depositing time. The most EPD films could be 90K zero resistance and the Jc values were over 1000A/cm2 (0 H, 77 K).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05b
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• pp.12-15
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• 2003

The YBaCuO thick film was deposited by the electrophoresis in the solution with different dimension particles. The morphology of the films deposited from different particles size was compared. The powder made by sol-gel method has the submicron particles, which deposit the most smooth film, and without microcracks after sintering. After sintering of the deposited film, the zone-melting process was carried out in low oxygen partial pressure (100 Pa) and Ag was used as substrate. And the zone-melted YBaCuO was studied by XRD.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1546-1548
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• 1998

Dual mode ring resonators(DMRR) have been fabricated using laser ablated $YBa_2Cu_3O_{7-x}$ superconducting thin films. The transition temperature of YBCO thin films were 85 - 88 K and the film thicknesses were about 5,000 $\AA$. Dual mode ring resonators were patterned by standard photolithography process and wet-etching. Then two-layer metal thin films (Ti/Ag) have been deposited for the ground plane on the back side of substrate by e-beam and thermal evaporation. The input/output feedline angles of each resonator were $60^{\circ}$, $100^{\circ}$, $180^{\circ}$. A network analyzer was used for testing the performance of the resonators in the frequency range of 6-13 GHz at 77 K.