• 한국결정성장학회지
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• 제14권2호
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• pp.58-62
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• 2004

The shape evolution of the interface void of copper metallization for intergrated circuits under electromigration stress is modeled. A 2-dimensional finite-difference numerical method is employed for computing time evolution of the void shape driven by surface diffusion, and the electrostatic problem is solved by boundary element method. When the diffusion coefficient is isotropic, the numerical results agree well with the known case of wedge-shape void evolution. The numerical results for the anisotropic diffusion coefficient show that the initially circular void evolves to become a fatal slitlike shape when the electron wind force is large, while the shape becomes non-fatal and circular as the electron wind force decreases. The results indicate that the open circuit failure caused by slit-like void shape is far less probable to be observed for copper metallization under a normal electromigration stress condition.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1995년도 제2회 단조심포지엄 단조기술의 진보
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• pp.100-123
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• 1995

The relationship between plastic deformation and crystal grain change in warm forging processes of SM100 carbon steel is studied. If the carbon steel is deformed in warm forging temperature (about recrystallization range), the crystal grain and cementite of the internal part are changed, so material properties are changed. Some experimental values, such as the elliptic degree of cementite, the grain size of cementitie and ferrite grain size, are investigated. When the plastic deformation proceeds, the elliptic degree of cementite becomes large, the grain size of cementite particle is small, and the size of ferrite grain appears fine by recrystallization. The elliptic degree of cementite has a considerable effect on formability. The distribution of effective strain in the forging is calculated by the rigid visco-plastic FEM analysis. The effective strain distribution obtained from the FEM simulation is compared with the experimental result. At effective strain 0.3 dynamic recovery and dynamic recrystallization begin, over 2.5 the organization of material has better quality that is suitable for the following cold forming.

• 한국결정성장학회지
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• 제4권2호
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• pp.131-133
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• 1994

$[0.5 \mu\textrm{m} (100) Si/(1102) sapphire]$ 기판상에 액상 에피탁시 방법으로 태양전지용 실리콘 박막형성을 시도하여, 평균 14 $\mu\textrm{m}$ 두께의 실리콘 박막을 아주 낮은 온도범위 $(380^{\circ}C~460^{\circ}C)$에서 성장시켰다.

• 한국세라믹학회지
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• 제27권2호
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• pp.249-255
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• 1990

High Tc Supperconducting thin films were fabricated by rf magnetron sputtering method. We have successfully controlled the compositions of films by adding sintered CuO pellets on YBa2Cu3O7-x single target. High Tc thin films with large grian size and good crystal habit were obtained by rapid thermal annealing process. The films deposited on SrTiO3(100) single crystal substrate indicated the existence of c-axis prefered orientation confirmed by XRD and SEM analysis. The Tc, zero's of sharp resistive transition for rapid annealed films deposited on polycrystalline YSZ substrate and on SrTiO3(100) single crystal substrate were 79K and 88K, respectively.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.563-563
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• 2012

We report a one-step fabrication of single-crystal organic nanowire arrays on substrates using a new direct printing method (liquid-bridge-mediated nanotransfer moulding, LB-nTM), which can simultaneously enable the synthesis, alignment and patterning of the nanowires using molecular ink solutions. Two- or three-dimensional complex structures of various single-crystal organic nanowires were directly fabricated over a large area with a successive process. The position of the nanowires can be aligned easily on complex structures because the mold is movable on substrates before drying the polar liquid layer, which acts as an adhesive lubricant. This efficient manufacturing method can produce a wide range of optoelectronic devices and integrated circuits with single-crystal organic nanowires.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.537-537
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• 2012

We have studied a fabrication of vapor phase polymerized Poly(3,4-ethylenedioxythiophene) (PEDOT) nanowire arrays for the first time. The vapor-phase polymerization (VPP) technique is a bottom-up processing method that utilizes the organic arrangement of macromolecules to easily produce ordered aggregates, including on the nanoscale, or prepare thin films of self-assembled molecules, micropatterns, or modified microstructures of pure conducting polymers. Also, liquid-bridge-mediated nanotransfer molding (LB-nTM), which was reported as a new direct patterning method recently, is for the arrayed formation of two- or three-dimensional structures with feature sizes as small as tens of nanometers over large areas up to 4 inches across and is based on the direct transfer of various materials from a mould to a substrate through a liquid bridge between them. The PEDOT nanowires grown by VPP method and transferred on a substrate to use LB-nTM method have been fabricated to single crystal PEDOT nanowires investigated Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and electrical properties.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.910-911
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• 2006

We newly designed and manufactured a new arranging system for a three-dimensional artificial crystal of monosized micro particles. In this system, a robotic micro-manipulator accurately locates the spherical particle onto the lattice point, and subsequently fiber lasers micro-weld the contact points between the neighboring particles. Actually, one- and two-dimensional arrays were constructed using monosized tin particles with the diameter of 400 m. Moreover, due to optimization of the process parameters, we successfully constructed the artificial crystals of simple cubic and diamond structures. In particular, the diamond structure which can represent a large photonic band gap is expected to progress toward a practical photonic crystal device.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.151-154
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• 2007

We demonstrate a novel selective patterning process of a semiconducting polymer for channel regions to fabricate an array of organic thin-film transistors (OTFTs). This process is applicable for various organic films over large area. A reflective liquid crystal display based on the OTFT array was produced using the selective patterning through a wettability control.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 추계학술대회
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• pp.166-167
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• 2019

Smart windows are used as windows and doors to determine cooling and heating efficiency in the construction field. It's characteristics can increase the energy saving efficiency. In addition, the function of the smart window that can control the light transmittance transmitted from the external environment of the building to the building according to the needs of the user is attracting attention. In this study, a liquid crystal cell capable of controlling light transmittance of 297 × 210 ㎟ was fabricated by using a liquid crystal device as an optical shutter. Analysis of transmittance change according to driving voltage and driving stability according to thermal environment, We confirmed the applicability of building exterior materials as smart windows.

• 반도체디스플레이기술학회지
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• 제11권2호
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• pp.39-43
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• 2012

This paper presents a study on the design of a pulling module for silicon ingot and an apparatus of manufacturing silicon single crystal ingot using the same method. The pulling module is conceptually designed by using TRIZ. Czochralski method(CZ) is representative way to manufacture single crystal ingot for wafers. The seed can be broken by high tension which is caused by large weight of a silicon ingot. The solution of this problem has been derived using 6SC(6 steps creativity)TRIZ. The pulling module is actuated by DC motor and rollers. High tension in the seed is removed by the rotate-elevate motion of rollers in the pulling module. A rubber belt is included in the rotate-elevate mechanism for increasing friction between rollers and silicon ingot.