• 전기의세계
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• v.22 no.2
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• pp.11-18
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• 1973

This paper reports some results of Si and SiO$_{2}$ films obtained from the expitaxial growth by hydrogen reduction of SiCI$_{4}$ with a hydrogen and carbon dioxide mixture in an epitaxial-deposition chamber. The deposited Si and SiO$_{2}$ are studied by observing the process parameters affecting the rate of deposition, and the quantitative properties at the interface of Si and SiO$_{2}$ are also considered briefly according to the results of the optical absorption and the voltage-current characteristic of MOS etc. using step etching procedure for oxide films.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.39-39
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• 2010

There have been many efforts to utilize the outstanding properties of graphene for macroscopic applications such as transparent conducting films useful for flexible/stretchable electronics. However, the lack of efficient synthesis, transfer, and doping methods limited the scale and the quality needed for the practical production of graphene films. In this presentation, we introduce ultra-large scale (~30 inch) synthesis and roll-to-roll transfer of graphene films showing excellent electrical and physical properties suitable for practical applications. Considering the outstanding scalability/processibility of roll-to-roll and CVD methods and the extraordinary flexibility/conductivity of graphene films, we expect the commercial production and application electrodes replacing the use of ITO can be realized in near future.

• Bulletin of the Korean Chemical Society
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• v.18 no.6
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• pp.594-599
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• 1997

A number of complexes of transition metal ions with some coumarin derivatives have been prepared and their structures were elucidated with the help of conductometric, photometric and infrared studies. The stability constants of various complexes were determined, in aqueous medium, at different temperatures potentiometrically. The thermodynamic characteristics, ΔG, ΔH and ΔS, were calculated. The electrical behaviour of prepared compounds was followed.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.201-206
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• 2006

Earth sciences is undergoing a gradual but massive shift from description of the earth and earth systems, toward process modeling, simulation, and process visualization. This shift is very challenging because the underlying physical and chemical processes are often nonlinear and coupled. In addition, we are especially challenged when the processes take place in strongly heterogeneous systems. An example is two-phase fluid flow in rocks, which is a nonlinear, coupled and time-dependent problem and occurs in complex porous media. To understand and simulate these complex processes, the knowledge of underlying pore-scale processes is essential. This paper presents a new attempt to use pore-scale simulations for understanding physical properties of rocks. A rigorous pore-scale simulator requires three important traits: reliability, efficiency, and ability to handle complex microstructures. We use the Lattice-Boltzmann (LB) method for singleand two-phase flow properties, finite-element methods (FEM) for elastic and electrical properties of rocks. These rigorous pore-scale simulators can significantly complement the physical laboratory, with several distinct advantages: (1) rigorous prediction of the physical properties, (2) interrelations among the different rock properties in a given pore geometry, and (3) simulation of dynamic problems, which describe coupled, nonlinear, transient and complex behavior of Earth systems.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.10
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• pp.438-442
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• 2005

Si nanocrystal (Si NC) memory device has several advantages such as better retention, lower operating voltage, reduced punch-through and consequently a smaller cell area, suppressed leakage current. However, the physical and electrical reasons for this behavior are not completely understood but could be related to interface states of Si NCs. In order to find out this effect, we characterized electrical properties of Si NCs embedded in a SiO$_{2}$ layer by scanning probe microscopy (SPM). The Si NCs were generated by the laser ablation method with compressed Si powder and followed by a sharpening oxidation. In this step Si NCs are capped with a thin oxide layer with the thickness of 1$\~$2 nm for isolation and the size control. The size of 51 NCs is in the range of 10$\~$50 m and the density around 10$^{11}$/cm$^{2}$ It also affects the interface states of Si NCs, resulting in the change of electrical properties. Using a conducting tip, the charge was injected directly into each Si NC, and the image contrast change and dC/dV curve shift due to the trapped charges were monitored. The results were compared with C-V characteristics of the conventional MOS capacitor structure.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.478-481
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• 2010

Antimony doped tin oxide (ATO) nanoparticles were added as nanofillers to UV-curable polyester-acrylate (PEA) resin for coating to improve thermal, mechanical, and electrical properties. In this study, ATO nanoparticles were grafted by 3-glycidyloxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane respectively to improve dispersion and interfacial adhesion. The physical properties and surface scratch hardness of the UV-curable nanocomposite coating were improved considerably by introducing the modified ATO nanoparticles.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.299-302
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• 2001

The unique physical properties of metal fibers have led to their wide application in different fields of machinery and electrical products. Especially, stainless steel(SS) fiber is used to the reinforcement of composites, textile and nonwoven materials for improving strength and electric properties. (omitted)

• Carbon letters
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• v.1 no.2
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• pp.76-81
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• 2000

Physical properties of artificial graphite electrodes were evaluated along three different directions; circumferential (X), radial (Y), and axial (Z) directions. Four kinds of commercial electrode products were used in this study for the evaluation; pole (AP) and nipple (AN) of manufacturer A, pole (BP) and nipple (BN) of manufacturer B. The mechanical, electrical, and thermal properties in X and Y directions were very similar to each other. In Z direction, however, the mechanical properties, including flexural strength and compressive strength, were higher, and electric resistance and thermal expansion were much lower than those in the other directions. The microstructures observed by optical microscope and scanning electron microscope revealed that the differences in properties by the measuring direction were caused by the preferential alignment of needle cokes along the Z direction. When comparing the properties of the electrode samples in the same direction, the mechanical properties mainly depended on the bulk density or porosity of the samples as well as preferential alignment of needle cokes.

• Transactions on Electrical and Electronic Materials
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• v.13 no.3
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• pp.144-148
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• 2012

In this work, we investigated to the etching characteristics of $TiO_2$ thin film and the selectivity using the inductively coupled plasma system. The etch rate and the selectivity were obtained with various gas mixing ratios. The maximum etch rate of $TiO_2$ thin film was 61.6 nm/min. The selectivity of $TiO_2$ to TiN, and $TiO_2$ to $SiO_2$ were obtained as 2.13 and 1.39, respectively. The etching process conditions are 400 W for RF power, -150 V for DC-bias voltage, 2 Pa for the process pressure, and $40^{\circ}C$ for substrate temperature. The chemical states of the etched surfaces were investigated with X-ray photoelectron spectroscopy (XPS). Its analysis showed that the etching mechanism was based on the physical and chemical pathways in the ion-assisted physical reaction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.421-424
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• 1996

Effects of humidity absorbing deterioration on AC dielectric breakdown characteristics of modified epoxy resin system with SN(succinonitrile) were investigated. As the forced humidity absorbing deterioration proceeded under high temperature and humidify, glass transition temperature increased. The dielectric breakdown strength increased and then decreased at deterioration cycles higher than 2. Not only, the increment of thermal stability but also, the physical detects such as Internal cracks and voids occurred during the humidity absorbing deterioration cycle were the main causes of the change in dielectric properties.