• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.10
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• pp.837-843
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• 2009

$TiO_2$(2 wt.%)-doped ZnO(TZO) films with thickness from 100 nm to 500 nm were prepared on polyethylene naphthalate(PEN) substrate under various rf-power range from 40 W to 80 W. Their electrical and optical properties were investigated as a function of rf-power. We think that these properties were closely related with the crystallization and the film density of TZO films. It was also presumed that the vaporization of the water vapor and other adsorbed particles such as an organic solvents can affect the electrical properties of the conventional transparent conductive oxide(TCO) films. On the other hand, since the TZO film deposited on glass substrate at room temperature with rf-power of 80 W shows a very low resistivity of $7.5\times10^{-4}\;\Omega{\cdot}cm$ and a very excellent transmittance over an average 85% in the visible range, that is comparable to that of ITO films. Therefore, we expect that the TZO films can be used as transparent electrode for optoelectronic devices such as touch-panels, flat-panel displays, and thin-film solar cells.

• Advances in concrete construction
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• v.2 no.3
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• pp.209-227
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• 2014

The use of limestone fines (LF) in mortar and concrete can in certain ways improve performance and thus has become more and more commonplace. However, although LF is generally regarded as a filler, it is up to now not clear how much filling effect it could have and how best the filling effect could be utilized. Herein, the packing density and filling effect of LF were studied by measuring the packing densities of LF, (LF + cement) blends and (LF + cement + fine aggregate) blends under dry and wet conditions, and measuring the performance of mortars made with various amounts of LF added. It was found that the addition of LF would not significantly increase the packing density of (LF + cement) blends but would fill into the paste to increase the paste volume and paste film thickness, and improve the flow spread and strength of mortar.

• Journal of the Semiconductor & Display Technology
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• v.14 no.1
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• pp.67-71
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• 2015

Pulse electroplating was studied to form nanocrystal structure effectively by changing plating current density and duty cycle. When both of plating current density and duty cycle were decreased from $100mA/cm^2$ and 70% to $50mA/cm^2$ and 30%, the P content in the Ni matrix was increased almost up to the composition of $Ni_3P$ compound and the grain growth after annealing was retarded as well. The as-plated hardness values ranging from 660 to 753 HV are mainly based on the formation of nanocrystal structure. On the other hand, the post-anneal hardness values ranging from 898 to 1045 HV, which are comparable to the hardness of hard Cr, are coming from how competition worked between the precipitation of $Ni_3P$ and the grain coarsening. According to the ANOVA and regression analysis, the plating current density showed more strong effect on nanocrystal size and film hardness than the duty cycle.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.1
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• pp.107-115
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• 2005

The effects on the formation of anodic oxide films on Mg-Al alloy (AZ91) in 1M-NaOH solution was investigated using parameters of current density and time during anodizing The general tendency has been confirmed that the increase of anodizing time improves the corrosion resistance. It is considered that the formation of anodic oxide film was increased by increasing the applied current and the anodizing time to generate active dissolution reaction In anodizing at constant current density. passivity potentials shifted to noble direction with increasing current densities. It was confirmed that oxygen quantify in anodic oxide films increased with anodizing time. The compact films above 4 $mA/cm^2$ were formed with the shape of an island in grooves at early stage and then grew with combination of the islands

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.50-50
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• 2011

The aluminum nitride films were prepared by RF magnetron sputtering using an AlN ceramic target. The crystallinity, grain size, Al-N bonding and thermal conductivity were investigated in dependence on the plasma power densities (4.93, 7.40, 9.87 W/$cm^2$) during sputtering. High thermal conductivity is important properties of A1N passivation layer for functioning properly in thermal inkjet printhead. The crytallinity, grain size, Al-N bonding formation and chemical composition were observed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. The AlN thin film was changed from amorphous to crystalline as the power density was increased, and the largest grain size appeared at medium power density. The near stoichiometry Al-N bonding ratio was acquired at medium power density. So, we know that the AlN thin film had better thermal conductivity with crystalline phase and near stoichometry Al-N bonding ratio at 7.40 W/$cm^2$ power density.

• Applied Science and Convergence Technology
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• v.23 no.2
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• pp.90-96
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• 2014

Flexible $ZrO_2$ films as dielectric materials for high-energy-density capacitors were deposited on polyethylene terephthalate (PET) substrates by RF magnetron sputtering. The growth behavior, microstructure and electrical properties of the flexible $ZrO_2$ films were dependent on the sputtering pressure and gas ratio. Although $ZrO_2$ films were deposited at room temperature, all films showed a tetragonal crystalline structure regardless of the sputtering variables. The surface of the film became a surface with large white particles upon an increase in the $O_2/Ar$ gas ratio. The RMS roughness and crystallite size of the $ZrO_2$ films increased with an increase in the sputtering pressure. The electrical properties of the $ZrO_2$ films were affected by the microstructure and roughness. The $ZrO_2$ films exhibited a dielectric constant of 21~38 at 1 kHz and a leakage current density of $10^{-6}{\sim}10^{-5}A/cm^2$ at 300 kV/cm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.125-128
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• 1999

(Ba$_{0.6}$Sr$_{0.4}$)TiO$_3$(BST) thin films were fabricated with different deposition temperature by Pulsed Laser Deposition(PLD). This BST thin films showed a maximum dielectric constant value of $\varepsilon$$_{r}$=~684 and dielectric loss was ~0.01 when substrate temperature was 75$0^{\circ}C$. Charge storage density of BST thin film was 4.733 [$\mu$C/$\textrm{cm}^2$] and estimated charging time was 0.15 nsec. Leakage current density of BST thin film was below 10$^{-7}$ [A/$\textrm{cm}^2$] at 3V. 3V.V.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.5
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• pp.340-346
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• 2021

The initial electrochemical performance of ceramic fuel cell with thin-film electrolyte fabricated by plasma-enhanced atomic layer deposition method was evaluated in terms of peak power density ratio, open circuit voltage ratio, and activation/ohmic resistance ratios at 500℃. Hydrogen and air were used as anode fuel and cathode fuel, respectively. The peak power density ratio reduced as ~52% for 30 min, which continually decreased as time increased but degradation rate gradually decreased. The open circuit voltage ratio decreased with respect time; however, its behavior was evidently different from the reduction behavior of the peak power density. The activation resistance ratio increased as ~127% for 30 min, which was almost similar with the reduction behavior of the peak power density ratio.

• Current Applied Physics
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• v.18 no.11
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• pp.1436-1440
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• 2018

SiN and SiCN film production using plasma-enhanced atomic layer deposition (PE-ALD) is investigated in this study. A developed high-power and high-density multiple inductively coupled plasma (multi-ICP) source is used for a low temperature PE-ALD process. High plasma density and good uniformity are obtained by high power $N_2$ plasma discharge. Silicon nitride films are deposited on a 300-mm wafer using the PE-ALD method at low temperature. To analyze the quality of the SiN and SiCN films, the wet etch rate, refractive index, and growth rate of the thin films are measured. Experiments are performed by changing the applied power and the process temperature ($300-500^{\circ}C$).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.147-150
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• 2007

Electro-deposition of carbon film on silicon substrate in methanol solution was carried out with various current density, solution temperature and electrode spacing between anode and cathode. The carbon films with smooth surface morphology and high electrical resistance were formed when the distance between electrode was relatively wider. The electrical resistance of the carbon films were independent of both current density and solution temperature.