• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 초전도 자성체
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• pp.37-40
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• 2002

Superconductor wire fabricated by electrophoresis showed its critical current density depended on parameters such as applied voltage and deposition time. Substrate and suspension solutions. and its properties are also important parameters. When same optimal parameter and condition was used, deposition density of superconductor film affect directly its critical current density. In this study, therefore, electrophoretic deposition technique was utilized for a densification of YBCO superconducting wire, and researches on electrophoretic suspension solutions and additive were experimentally performed for an improvement of the critical current density of fabricated electrophoretically superconducting wire. The samples fabricated in the solution with the additive, 8 vol.% of 1% PEG(1000), showed the highest critical current density.

• Journal of Welding and Joining
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• 제18권6호
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• pp.96-101
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• 2000

Sintered alumina ceramic substrate has been used for the insulating substrate for thick Hybrid IC owing to its cheapness and good insulating properties. Some of thick HIC's are important to eliminate the heat emitted from the parts that are mounted on the ceramic substrate. Sintered ceramic substrate can not transfer and emit the heat efficiently. It's been tried to do plasma spray coating of alumina ceramic on the metal substrates that have a good heat emission property. The most important properties to commercialize this ceramic coated metal substrate are surface roughness and deposition efficiency. In this study, plasma spray coating parameters are optimized to minimize the surface roughness and to maximize the deposition efficiency using Taguchi experimental method. By this optimization, the deposition efficiency was greatly improved from 35% at the frist time to 75% finally.

• 한국세라믹학회지
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• 제52권5호
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• pp.315-319
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• 2015

Yttria-stabilized zirconia (YSZ)-based micro tubular SOFC single cells were fabricated by electrophoretic deposition (EPD) process. Stable slurries for the EPD process were prepared by adding phosphate ester (PE) as a dispersant in order to control the pH, conductivity, and zeta-potential. NiO-YSZ anode support, NiO-YSZ anode functional layer (AFL), and YSZ electrolyte were consecutively deposited on a graphite rod using the EPD process; materials were then co-sintered at $1400^{\circ}C$ for 4 h. The thickness of the deposited layer increased with increasing of the applied voltage and the deposition time. A YSZ-based micro tubular single cell fabricated by the EPD process exhibited a maximum power density of $0.3W/cm^2$ at $750^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 춘계학술대회 논문집
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• pp.117-121
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• 1992

Zinc oxide thin films were obtained from zinc acetate-2-water and oxygen by photo-CVD method. (1) The formation of ZnO films sarts from 100[$^{\circ}C$] and the deposition rate increases with increasing substrate temperature. (2) The rate of deposition was also affected by flow rates of O$_2$(reaction gas) and N$_2$(Carrier gas). (3) The deposition rate decreases with increasing O$_2$mole rate. (4) The transmission of the films was independent of oxygen mole rate and it was largely affected substrate temperature. (5) The electric resistivity of th films was largely varied at oxygen mole rate 10[%] and above 20[%], a plateau was encountered. Also, it increases with increasing substrate temperature. As the results, at substrate temperature: 200[$^{\circ}C$]; O$_2$gas mole rate:10[%]; reation time:10[min] pressure: 10$\^$-2/[atm], deposition rate; transmittance; resistivity were 780[A$\^$0/; 94[%]; 7${\times}$10$\^$-2/[$\Omega$$.$cm] respectively.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.521-522
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• 2006

Laser additive direct deposition of metals is a new rapid manufacturing technology, which combines with computer aided design, laser cladding and rapid prototyping. The advanced technology can build fully-dense metal components directly from CAD files with neither mould nor tool. Based on the theory of this technology, a promising rapid manufacturing system called "Laser Metal Deposition Shaping (LMDS)" is being developed significantly. The microstructure and mechanical properties of the LMDS-formed samples are tested and analyzed synthetically. As a result, significant processing flexibility with the LMDS system over conventional processing capabilities is recognized, with potentially lower production cost, higher quality components, and shorter lead time.

• 한국재료학회지
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• 제9권6호
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• pp.604-608
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• 1999

Semiconductor industry requires the development of new technology such as 300 mm technology, suitable for manufacturing the next generation dervices. A promising process for realizing 300 mm technology can be achieved by using enlarged microwave plasma chemical vapor deposition (MWCVD) technology. In this work, we used radial line slot antenna for enlarging microwave plasma area, and carried ut the deposition of polysilicon films using enlarged MWCVD for the first time in Korea. The results was as follows. Deposited polysilicon films showed various degrees of crystallinity as well as epitaxy to silicon substrates even at low temperature of $300^{\circ}C$. Deposition rates also controled crystallization behavior and slo deposition rates showed very high crystallinity. It could be said that enlarged MWCVD system and technology was worth to get attraction as one os future technologies for 1 G DRAM era.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2005년도 추계학술발표회 및 workshop
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• pp.158-159
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• 2005

• 한국전기전자재료학회논문지
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• 제26권12호
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• pp.909-914
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• 2013

CIGS is one of thin film solar cell and has been studied so much, because of the possibility of low price and high efficiency. Until now, co-evaporation and sputtering were typical method to prepare CIGS absorption layer, and a few company commercialized solar cell by these method. However, non-vacuum process which has been studied for long time has not been progressed, though the merit of low price. Especially, aerosol deposition method has not been reported, because it is difficult to prepare a large quantity of various CIGS powder. In this study, CIGS powder was synthesized by mechanochemical method and CIGS absorption layer was deposited by aerosol deposition method. The thickness of the CIGS layer was controlled by the number of deposition and the surface roughness of it was affected by the amount of flow gas. And, also, I-V curve of it appeared metallic property in the case of 'as deposition'. After heat treatment in Se-rich atmosphere, the electrical property of it changed to a semiconductor. CdS and transparent conduction layer were formed by a typical method on it for solar cell. The efficiency of cell was appeared 0.19%. Though the efficiency was low because of the disharmony in the after-process, it was conformed that CIGS solar cell could be prepared by aerosol deposition.

• 한국가스학회지
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• 제21권1호
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• pp.1-5
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• 2017

독성가스 사고 시 토양 침적은 사고피해범위에 영향을 미치는 주요 변수이다. 본 연구에서는 토양의 깊이 및 유기물 함량 비율이 독성가스 염소의 토양 침적 특성에 미치는 영향을 연구하였다. 실험에 이용된 장치로는 미국의 Air Force Research Laboratory에서 구축한 장치를 벤치마킹하였다. 다양한 합성토양을 이용해 유기물의 함량을 변화시키면서 토양 침적실험을 진행하였다. 다양한 합성토양에 일정 농도의 염소를 노출시킨 후, 염소 침적의 정도를 정량화하기 위해 음이온 크로마토그래피를 이용하여 침적량을 측정하였다. 그 결과, 토양 표면에서의 침적량 변화에 비해 깊이에 따른 침적량의 변화 경향은 볼 수 없었으나, 염소 노출 시간에 따른 표면 침적량의 차이는 증가함을 확인 할 수 있었다. 또한, 유기물 함량에 따른 침적량은 유기물 함량이 증가함에 따라 비례관계를 보였다. 토양 표면에서의 염소 침적량의 증가는 주로 토양 내 유기물 함량에 의존함을 확인하였다.

• Nuclear Engineering and Technology
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• 제55권7호
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• pp.2628-2641
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• 2023

Nuclear safety is the lifeline for the development and application of nuclear energy. In severe accidents of pressurized water reactor (PWR), aerosols, as the main carrier of fission products, are suspended in the containment vessel, posing a potential threat of radioactive contamination caused by leakage into the environment. The gas-phase aerosols suspended in the containment will settle onto the wall or sump water through the natural deposition mechanism, thereby reducing atmospheric radioactivity. Aiming at the low accuracy of the aerosol model in the ISAA code, this paper improves the natural deposition model of aerosol in the containment. The aerosol dynamic shape factor was introduced to correct the natural deposition rate of non-spherical aerosols. Moreover, the gravity, Brownian diffusion, thermophoresis and diffusiophoresis deposition models were improved. In addition, ABCOVE, AHMED and LACE experiments were selected to validate and evaluate the improved ISAA code. According to the calculation results, the improved model can more accurately simulate the peak aerosol mass and respond to the influence of the containment pressure and temperature on the natural deposition rate of aerosols. At the same time, it can significantly improve the calculation accuracy of the residual mass of aerosols in the containment. The performance of improved ISAA can meet the requirements for analyzing the natural deposition behavior of aerosol in containment of advanced PWRs in severe accident. In the future, further optimization will be made to address the problems found in the current aerosol model.