• Journal of the Microelectronics and Packaging Society
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• v.9 no.3
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• pp.1-6
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• 2002

A low temperature process technology of copper thin films has been developed by a chemical vapor deposition technology for multi-level metallzations in ULSI fabrication. The copper films were deposited on TiN/Si substrates in helium atmosphere with the substrate temperature between $130^{\circ}C$ and $250^{\circ}C$. In order to get more reliable metallizations, effects on the post-annealing treatment to the electrical properties of the copper films have been investigated. The Cu films were annealed at the $5 \times10^{-6}$ Torr vacuum condition and the electrical resistivity and the nano-structures were measured for the Cu films. The electrical resistivity of Cu films shown to be reduced by the post-annealing. The electrical resistivity of 2.0 $\mu \Omega \cdot \textrm{cm}$ was obtained for the sample deposited at the substrate temperature of $180^{\circ}C$ after vacuum annealed at $300^{\circ}C$. The resistivity variations of the films was not exactly matched with the size of the nano-structures of the copper grains, but more depended on the contamination of the copper films.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.540-542
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• 2009

Phosphorus doped ZnO (PZO) thin films were deposited on $SiO_2$/n-Si substrates using DC magnetron sputtering system varying oxygen partial pressures from 0 to 40 % under Ar atmosphere. The deposited films showed reduced n-type conductivity due to the compensating donor effects by phosphorus dopant. The bias-time stability shows relatively good stability over bias and time comparing to un-doped ZnO-based TFTs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.105-108
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• 1998

In the present study, the luminescence characteristics and the effect of conductivity on cathodoluminescene of CaTiO$_3$:Pr was studied using dick specimens sintered at various temperatures and atmosphere. As a sintering temperature was increased from 1100 to 1400 $^{\circ}C$, conductivity of CaTiO$_3$:Pr phosphor was improved and CL brightness was also increased about four times and decay times was reduced from 0.29 to 0.21 msec. And all samples prepared in Ar showed high conductivity, CL brightness and short decay time in comparison with those sintered in air.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.3
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• pp.44-54
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• 1996

The release of polluting gases such as NO/sub x/ of SO/sub x/ to the atmosphere from ships is causing increasing concern. To reduce destruction to the marine environment, the value of the utilization of photovoltaic energy is highly appreciated since photovoltaic energy is and alternate clean energy source to fossil fuels. The use of a photovoltaic generating system to supplement diesel engine driven electric power system on ships has been studied. The design of the photovoltaic generating system based on a photovoltaic array is presented in this paper. The amount of NO/sub x/ and SO/sub x/ emission is found to be significantly reduced for a small vessel operated within a harbour after a photovoltaic generating system is installed to supplement the diesel engine generator system.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.180-182
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• 2002

Copper thin films are prepared by a chemical vapor deposition technology for multi-level metallzations in ULSI fabrication. The copper films were deposited on TiN/Si substrates in helium atmosphere with the substrate temperature between $120^{\circ}C$ and $300^{\circ}C$. In order to get more reliable metallizations, effects on the post-annealing treatment to the electrical properties of the copper films have been investigated. The Cu films were annealed at the $5\times$10^{-6}$ Torr vacuum condition, and the electrical resistivity and the nano-structures were measured for the Cu films. The electrical resistivity of Cu films shown to be reduced by the post-annealing. The electrical resistivity of 2.2 $\mu$$\Omega$.cm was obtained for the sample deposited at the substrate temperature of $180^{\circ}C$ after vacuum annealed at $300^{\circ}C$. The resistivity variations of the films was not exactly matched with the size of the nato-structures of the copper grains, but more depended on the deposition temperature of the copper films.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.3
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• pp.264-269
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• 2016

A simple dry chemical approach was developed in order to load palladium (Pd) as a promoter on Pt/gas diffusion electrode (GDE) for polymer electrolyte membrane fuel cell (PEMFC). Palladium(II) bis (acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into Pt/GDE and then reduced to Pd nanoparticles simultaneously without any reducing agent and any solvent in a glass reactor of $N_2$ atmosphere at $180^{\circ}C$ for 3, 5 and 15 min. Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

• 전기의세계
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• v.28 no.9
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• pp.43-50
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• 1979

Silicon nitride films were chemically deposited on silicon substrates by reacting SiCl$_{4}$ and NH$_{3}$ in a nitrogen atmosphere at 700~1100 .deg.C. The deposition rate increased rapidly with deposition temperature upto about 1000 .deg.C, and became less temperature dependent above this temperature. The etch rate of films in buffered HF solution decreased, with an increase of deposition temperature, and a heat treatment at a temperature higher than that of the deposition considerably reduced the etch rate. It indicates that the heat treatment resulted in a densification of the films. Surface charge density of 3~4 * 10$^{11}$ /cm$^{2}$ was determined from the C-V characteristics of MNS diode, and it was also found that surface charge density depended on deposition temperature, but not film thickness. The current-voltage characteristics displayed a logI-V$^{1}$2/ dependence in the temperature range of 300~500.deg.K. Measurement of the slope of this characteristics and its dependence on temperature and bias polarity suggest that conduction in sili con nitride films arises from the Poole-Frenkel mechanism.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.451-454
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• 2001

The ionic conductivity of cubic solid solutions in the system Y$_2$O$_3$-ZrO$_2$ prepared by SHS was examined. Conductivity-temperature data obtained at 1000$^{\circ}C$ in atmosphere of low oxygen partial pressure (10$\^$-40/ atm) for Y$_2$O$_3$-ZrO$_2$ cubic solid solutions indicated that these materials could be reduced, the degree of reduction being related to the measuring electric field. At low impressed fields no reduction was observed. Thus, these conductivity data give a transference number for the oxygen ion in Y$_2$O$_3$-ZrO$_2$ cubic solid solutions greater than 0.99.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.218-225
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• 2007

A lactic acid bacterium capable of anaerobic respiration was isolated from soil with ferric iron-containing glucose basal medium and identified as L. garvieae by using 16S rDNA sequence homology. The isolate reduced ferric iron, nitrate, and fumarate to ferrous iron, nitrite, and succinate, respectively, under anaerobic $N_2$ atmosphere. Growth of the isolate was increased about 30-39% in glucose basal medium containing nitrate and fumarate, but not in the medium containing ferric iron. Specifically, metabolic reduction of nitrate and fumarate is thought to be controlled by the specific genes fnr, encoding FNR-like protein, and nir, regulating fumarate-nitrate reductase. Reduction activity of ferric iron by the isolate was estimated physiologically, enzymologically, and electrochemically. The results obtained led us to propose that the isolate metabolized nitrate and fumarate as an electron acceptor and has specific enzymes capable of reducing ferric iron in coupling with anaerobic respiration.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.4
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• pp.349-355
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• 2002

The ionic conductivity of cubic solid solutions in the systems of CaO-$ZrO_2$, $Y_2O_3-ZrO_2$ prepared by SHS was examined. The higher conductivity appears to be related to a lower activation energy rather than to the number of oxygen vacancies dictated by composition. Conductivity-temperature data was obtained at 1000 $^{\circ}C$ in atmosphere of low oxygen partial pressure (~$10^{-40}$ atm) for $Y_2O_3-ZrO_2$ cubic solid solutions. The data indicated that these materials could be reduced, and the decree of reduction would be related with the measuring electric field.