• Journal of the Korean Ceramic Society
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• v.31 no.10
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• pp.1089-1098
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• 1994

The effect of Si3N4 addition on the microstructure and PTCR characteristics of BaTiO3 was studied. When 0.1 mol% Sb2O3-doped BaTiO3 codoped with Si3N4 (0.1, 0.25, 0.5, 0.75, and 1 wt%, respectively) were sintered, their microstructures were changed by the amount of the liquid phase as a result of eutectic reaction at 126$0^{\circ}C$. By these microstructural changes, the specific resistivity ratio($\rho$max/$\rho$min) with Si3N4 content variation of 0.1 mol% Sb2O3-doped BaTiO3 ceramics sintered at 130$0^{\circ}C$ for 1 hour varied between 3.70$\times$102(0.1 wt% Si3N4) to 1.16$\times$103 (1wt% Si3N4).

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1603-1605
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• 1996

We have studied the static electricity and optical retardation generated by rubbing the surfaces of polyimide (PI) and polyamide (PA) films. The static electricity increases with the rubbing strength (RS) and varies with the different PI films. We also investigated how the differences in the rubbing fabric affects the magnitude of the induced static electricity; the order of this effect is nylon > rayon > cotton. The induced static electricity is not only directly related to the values of the specific resistivity of the rubbed PI films, but also the RS and the ability of the rubbing fabric to generate and add a static electric charge. The order of the optical retardation produced by the rubbing fabraic on rubbed PI films is nylon > rayon > cotton, coinciding with the order of the generated static electricity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.226-229
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• 2001

To achieve ZnO layer with a high resistance, a new sputtering method with a Ramp method and cycled power process mode was developed. The specific resistance of the layers was in rang of $3*10^{10}{\Omega}cm$ to $2*10^{11}{\Omega}cm$. The characteristics of. ZnO thin films changed with working pressure and Ramp method were investigated by XRD(x-ray diffractometer), and SEM (scanning electron microscopy) analyses. This paper presents calculated and measured results for structures with thin ZnO layers. Measurements of SAW properties using thin ZnO layered structures will be shown. Also presented are results on the quality of ZnO films and specifics of the deposition process.

• Journal of Powder Materials
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• v.7 no.1
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• pp.6-11
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• 2000

Two kinds of Bi2Te3 powders, pure Bi2Te3/2vol.%ZrO2, have been prepared by a mechanical grinding process process. Effect of mixing of the powders on thermoelectric of the sintered body has been investigated by measuring Seebeck Coeffcient, specific electric resistivity and thermal conductivity. With an increase in the weight fraction of the Bi2Te3/2vol.%ZrO2 powder from 0 to 40wt.%. Especially, the figure of merit of the mixedBi2Te3 sintered body increases and thereafter dedreases above 40wt.%. Especially. the figure of merit of the mixed Bi2Te3 sintered bodies with mixing of Bi2Te3/2vol.%ZrO2 powder increased about 1.3time in comparison with the value of the specimen before mixing. Mixing of two kinds of Bi2Te3 powders which have different theramal and electric propertries with each other seemed to be useful methob to increase the figure of merit of Bi2Te3 sintered body.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.57-57
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• 2018

Zinc-oxide (ZnO), II-VI semiconductor with a wide and direct band gap (Eg: 3.2~3.4 eV), is one of the most potential candidates to substitute for ITO due to its excellent chemical, thermal stability, specific electrical and optoelectronic property. However, the electrical resistivity of un-doped ZnO is not low enough for the practical applications. Therefore, a number of doped ZnO films have been extensively studied for improving the electrical conductivities. In this study, Ti-doped ZnO films were successfully prepared by atomic layer deposition (ALD) techniques. ALD technique was adopted to careful control of Ti doping concentration in ZnO films and to show its feasible application for 3D nanostructured TCO layers. Here, the structural, optical and electrical properties of the Ti-doped ZnO depending on the Ti doping concentration were systematically presented. Also, we presented 3D nanostructured Ti-doped ZnO layer by combining ALD and nanotemplate processes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.2
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• pp.169-172
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• 2002

The voltage holding ratio(VHR) and the residual DC property in the in-plane switching (IPS) cells on a polyimide surface was studied. Several IPS cells which have different concentrations of cyano liquid crystals (LCs) were fabricated. We found that the VHR of the IPS cell was decreased with increasing concentration of cyano LCs. Also, the VHR of the IPS cell was increased with increasing specific resistivity of fluorine LCs. The residual DC voltage of the IPS cell by capacitance-voltage (C-V) hysteresis method was decreased with increasing concentration of cyano LCs. The residual DC property of the IPS cell on the rubbed PI surface can be improved by high polarity of cyano LC.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.4
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• pp.555-562
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• 1990

Alloyed ohmic contact properties of Au-Zn/Au, Au-Be/Au,Au-Zn/Cr/Au, and Au-Be/Cr/Au metal system to p-InP were investigated. Optimum alloying conditions were obtained at the annealing temperature of 425\ulcorner for all the metal systems using a rapid thermal annealing system. Surface AES analysis and auger depth profiling were done for each metal system annealed at the optimum conditions. Outdiffusions of In and P from the InP substrate were found in the metal systems without Cr intermediate layer. Also, small amount of In. P and Cr were detected at the surface in the case of Au-Zn/Cr/Au system, while there were occured no outdiffusion of In, P, and Cr for Au-Be/Cr/Au system. The best surface morpholoty and specific contact resistivity of 4.5x 10**-5 \ulcornercm\ulcornerhave been obtained in this Au-Be/Cr/Au material system alloyed at 425\ulcorner for 60 second.

• Journal of the Korean Ceramic Society
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• v.33 no.2
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• pp.183-191
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• 1996

For the fabrication of semiconducting BaTiO3 ceramics at lower sintering temperature BN was selected as a sintering aid and the microsturcture of semiconducting BaTiO3 ceramics and PTCR characteristics by their microstructural changes were investigated. by adding BN to 0.1 mol% Sb2O3-doped BaTiO3 ceramics the sintering temperature showing semiconducting BaTiO3 ceramics was reduced by 16$0^{\circ}C$ from 130$0^{\circ}C$ to 114$0^{\circ}C$ and the specific resistivity ratio was increased as the amount of BN was increased.

• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.279-284
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• 2002

All-vanadium redox flow battery(VRFB) has been studied actively as one of the most promising electrochemical energy storage systems for a wide range of applications such as electric vehicles, photovoltaic arrays, and excess power generated by electric power plants at night time. CPCS has been shown to have the characteristics as an excellent current collector for VRFB and electrochemical properties of specific resistivity 0.31 $\Omega$cm, which were composed of G-1028 80 wt%, PVC 10 wt%, DBP 5 wt% and FS 5 wt%. Energy efficiencies of VRFB with the CPCE and the existing electrode assembly were 84.14 % and 77.24 % respectively, in charge/discharge experiments at constant current of 200 mA, and the CPCE was confirmed to be suitable as the electrode of VRFB.

• Journal of the Korean institute of surface engineering
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• v.41 no.1
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• pp.23-27
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• 2008

The effect of solution agitation on the copper electroless deposition process of ULSI (ultra large scale integration) interconnections was investigated by using physical, electrochemical and electrical techniques. It was found that proper solution agitation was effective to obtain superconformal copper configuration within the trenches of $130{\sim}80nm$ width. The transition of open potential during electroless deposition process showed that solution agitation induced compact structure of copper deposits by suppressing mass transfer of cuprous ions toward substrate. Also, the specific resistivity of copper layers was lowered by increasing agitation speed, which made the deposited copper particles smaller. Considering both copper deposit configuration and electric property, around 500 rpm of solution agitation was the most suitable for the homogeneous electroless copper filling within the ultra-fine patterns.