• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1388-1390
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• 1995

The characteristic of dielectric breakdown in solid insulating material dominates the reliability and safety of power equipment and affects directly to its life. In this point of view, the thickness and temperature dependence of dielectric breakdown strength and mechanism of dielectric breakdown in low density polyethylene which has been employed widely as insulating material have been technically reviewed by examinations of thermal property. The dielectric breakdown strength depending on its thickness was measured 2.6[MV/cm] at the thickness of 20[${\mu}m$] and 1.9[MV/cm] at the thickness of 75[${\mu}m$] based on ambient temperature of 30[$^{\circ}C$]. It is shown the temperature dependence that dielectric breakdown strength decreases in linear as the thickness increases. The dielectric breakdown strength depending on temperature was measured 2.6[MV/cm] at the temperature of 30[$^{\circ}C$], 1.6[MV/cm] at 60[$^{\circ}C$] and 1.3[MV/cm] at 90[$^{\circ}C$] based on the thickness of 20[${\mu}m$]. As the ambient temperature increases, the temperature dependence is shown that a very large drop is occurred up to temperature of 60[$^{\circ}C$] and a very small drop is discovered over 60[$^{\circ}C$].

• Journal of the Korean institute of surface engineering
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• v.56 no.3
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• pp.169-179
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• 2023

This work studies dielectric breakdown behavior of AAO (anodic aluminum oxide) films formed on pure aluminum at a constant current density in 5 ~ 20 vol.% sulfuric acid (SA) and 2 ~ 8 wt.% oxalic acid (OA) solutions. It was observed that dielectric breakdown voltage of AAO film with the same thickness increased with increasing concentration of both SA and OA solutions up to 15 vol.% and 6 wt.%, respectively, above which it decreased slightly. The dielectric breakdown resistance of the OA films appeared to be superior to that of SA films. After dielectric breakdown test, cracks and a hole were observed. The crack length increased with increasing SA film thickness but it did not increase with increasing OA film thickness. To explain the reason why shorter cracks formed on the OA films than the SA films after dielectric breakdown test, the generation of tensile stresses at the oxide/metal interface was discussed in relation to porosity of AAO films obtained from cross-sectional morphologies.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1990.10a
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• pp.102-104
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• 1990

In this paper, we studied and investigated as to temperature dependence of dielectric breakdown properties, and the dielectric breakdown properties, and deterioration-proof properties due to interface treatment effect. In the result, we knew that temperature dependence of dielectric breakdown strength due to filler content was decreased, identified that D.C. dielectric breakdown strength was improved at the filler content 50[%]. When the D.C. voltage was applied to the non silane and silane treated specimens deal with mechanical deterioration, the dielectric breakdown strength was improved at the 150[%].

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1526-1528
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• 1996

The dielectric reliability of a polycrystalline and a multilayered $BaTiO_3$ thin films was evaluated using a time-zero dielectric breakdown (TZDB) and a time-dependent dielectric breakdown (TDDB) techniques. The $BaTiO_3$ thin films were prepared by rf-magnetron sputtering technique on ITO-coated glass substrates. In case of the multilayered $BaTiO_3$ thin film, the dielectric breakdown histogram, which was obtained from the TZDB measurements, showed a typical Weibull distribution. While in case of polycrystalIine $BaTiO_3$ thin film, a randomly distributed dielectric breakdown histogram was observed. The TDDB results of the multilayered $BaTiO_3$ thin film guaranteed about $10^5$ hours-operation under the stress field of 1 MV/cm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.12
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• pp.1118-1123
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• 2008

High voltage multilayer ceramic capacitors (MLCCs) are classified into two classes-those for temperature compensation (class I) and high dielectric constant materials (class II). We manufactured high voltage MLCC with temperature coefficient characteristics of C0G and X7R and studied the characteristics of electric properties. Also we studied the characteristics of dielectric breakdown voltage (V) as the variation of thickness in the green sheet and how to pattern the internal electrodes. The dielectric breakdown by electric field was caused by defects in the dielectric materials and dielectric/electrode interface, so the dielectric thickness increased, the withstanding voltage per unit (E) thickness decreased. To overcome this problem, we selected the special design like as floating electrode and this design affected the increasing breakdown voltage(V) and realized the constant withstanding voltage per unit thickness(E). From these results, high voltage application of MLCCs can be expanded and the rated voltage can also be develop.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.1
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• pp.39-44
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• 1999

The dielectric layers in AC plasma display panel(PDP) are essential to the discharge cell structure, because they protect metal electrodes from sputtering by positive ion bombarding in discharge plasma and form a sheath of wall charges which are essential to memory function of AC PDP. This layer should have high dielectric breakdown voltage, and also be transparent because the luminance of PDP is strongly correlated this layer. In this paper, we discussed the dielectric breakdown voltage and transparency of the dielectric layer under various conditions. As a result, on the $15\mum$ thickness, the minimum dielectric breakdown voltage was 435V and the transmission coefficient was about 80% after $570^{\circ}C$ firing process. It can be proposed that the resonable dielectric thickness in AC PDP is $15\mum$ because it has about 75V margin on the maximum applied voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.114-118
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• 2005

In this study, the DC dielectric breakdown of epoxy composites used for molding material was experimented and then its data were simulated by Weibull distribution equation. From the analysis of Weibull distribution, it was confirmed that as the allowed breakdown probability was given by 0.1[%], the applied field value needed to be under 21.5[kV/mm].

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.8
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• pp.685-689
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• 2005

In the fabrication and design of MLCCs (Multilayer Ceramic Capacitors) with Ni inner electrode for medium and high voltage, reliability and dielectric breakdown mode have been investigated. For thickness of green sheet, the relationship between the rated voltage versus the thickness of green sheet. Increasing the thickness of green sheet increases the dielectric breakdown voltage. However, a practical limit to this linear relationship occurs at 30 urn and above. As the thickness of green sheet increased, dielectric breakdown voltage and weibull coefficient is increased, but abruptly decrease at 30 urn and 36 urn. When 24 urn of green sheet thickness, weibull coefficient and dielectric breakdown voltage were 13.58 and 70 V/um respectively. The results enabling the MLCCs to demonstrate high levels of reliability at medium and high voltage.

• Electrical & Electronic Materials
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• v.7 no.6
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• pp.527-533
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• 1994

In this study, it was studied on dielectric breakdown strength and thennostability properties due to the structure variation of matrix resin and treatment of coupling agent of epoxy insulating materials. The interpenetrating network structure was formed by simultaneous heating curing the epoxy resin with single network structure and the methacrylic acid resin. Also inner structure was observed and the glass transition temperature was measured on these three type specimens. Dielectric breakdown properties were investigated by applying DC, AC and impulse voltage. As a result, the glass transition temperature and the dielectric breakdown strength of specimen with interpenetrating network structure was more higher than another two type specimens.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.164-167
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• 1997

A series of interpenetrating polymer networks(IPN) based on Epoxy, MA and PU were synthesized in order to improve withstand voltage properties of Epoxy resin. Dielectric breakdown characteristics are investigated for six types of specimens. As a result, it was found that impulse voltage dielectric breakdown characteristic of SIN specimen was the most excellent. It was also found that SIN specimens were stronger than anything else in scanning electron microscopy. On the other hand, as a result of consideration of dielectric breakdown strength change according to adding fi1ter, it was confirmed that the decrease of dielectric breakdown strength are controlled slightly by IPN method.