• Journal of the Microelectronics and Packaging Society
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• v.9 no.3
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• pp.57-67
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• 2002

Increased signal speed can be obtained in three ways: changing the layout and/or the ratio of the width to thickness of the metal lines, decreasing the specific resistance of the interconnect metal, and decreasing the dielectric constant of the insulating material (intermetal dielectric). Further advancement cannot be expected from changing layout or decreasing specific resistance. The only alternative is to use an insulating material with a lower dielectric constant than other ones used presently. A large variety of polymers has been proposed for use as materials with low dielectric constants for applications in microelectronics. In this review, the properties of selected polymers as well as various fabrication methods for polymer thin films are discussed. Based on the properties described so far, and the requirements for applications as intermetal dielectric material, the possibilities for further developments also are discussed.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.357-360
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• 2006

In this study, we studied the physical properties and application of PF foam as heat insulating materials. In the experimental results, the density of PF foam showed $0.030g/cm^3$ and the thermal conductivity showed $0.026kcal/m.h.^{\circ}C$. Also, thermal resistance of the prepared PF foam was volatilized about 71.7 wt% when the temperature was $500^{\circ}C$ (1 h). And the chemical structure of PF foam have a closed cell type in the important properties as heat insulating materials. Therefore, it was confirmed that the prepared PF foam had excellent performance as heat insulating materials.

• Tribology and Lubricants
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• v.1 no.1
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• pp.59-68
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• 1985

Processes such as vacuum distillation, mixed solvent extraction, neutralization and clay treatment were used to refine an electrical insulating oil, The improved reused oil showed an excellent copper corrosion resistance and gave a better oder than that of oil refined from the conventional acid treatment method.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.409-413
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• 1999

Recently, the polymeric insulators have been accepted in several countries for the outdoor high voltage applications. In comparison with the conventional porcelain, polymeric insulators offer various advantages such as light weight, superior vandal resistance and better contamination performance. The outdoor polymeric insulating materials such as silicone rubber, ethylene propylene diene monomer(EPDM), ethylene vinyl acetate(EVA) and epoxy are aged such as silicone rubber, ethylene propylene diene monomer(EPDM), ethylene vinyl acetate(EVA) and epoxy are aged under the various natural environment with the long-term performance in outdoor. In this paper, the effects of UV-under the various natural environment with the long-term performance in outdoor. In this paper, the effects of UV-ray on the surface of silicone rubber were investigated by using the weather-Ometer. The accelerated aging stresses were simulated by UV radiation, high temperature and humidity as well as water spray. These aging characteristics were examined through contact angle measurements, tracking resistance test, FT-IR and SEM/EDS analysis. The experimental results showed that tracking resistance decreases with increase in the UV-ray irradiation period. But the surface of silicone rubber kept hydrophobicity. It is found that the inorganic filler such as)$ Al(OH_3$ improves tracking resistance and the $Tio_2$is very effective in preventing degradation of silicone rubber surface from UV-ray.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.12
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• pp.596-600
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• 2004

In this study, the surface properties of PET film were analyzed after plasma surface treatment. After plasma treatment of surface roughness and XPS were evaluated to analyze the chemical property, while the surface potential decay and surface resistance rate was measured to analyze the electric관 characteristic. When plasma discharge treatment was conducted for less than 10 minutes, the electrical insulating property was improved by evaporation of low molecular weight materials and cleaning of surface. However, when the treatment was conducted for more than 10 minutes, the insulating property was decreased due to excessive discharge energy. Analyses of chemical characteristics showed that 10-minute treatment resulted in increase of C-O and O=C-O bonds. However, when treated for more than 10 minutes. they were relatively decreased.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.132-132
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• 2011

The sheet resistance (Rs) of undoped GaN films on AlN/c-plane sapphire substrate was investigated in which the AlN films were grown by R. F. magetron sputtering method. The Rs was strongly dependent on the AlN layer thickness and semi-insulating behavior was observed. To clarify the effect of crystalline property on Rs, the crystal structure of the GaN films has been studied using x-ray scattering and transmission electron microscopy. A compressive strain was introduced by the presence of AlN nucleation layer (NL) and was gradually relaxed as increasing AlN NL thickness. This relaxation produced more threading dislocations (TD) of edge-type. Moreover, the surface morphology of the GaN film was changed at thicker AlN layer condition, which was originated by the crossover from planar to island grains of AlN. Thus, rough surface might produce more dislocations. The edge and mixed dislocations propagating from the interface between the GaN film and the AlN buffer layer affected the electric resistance of GaN film.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.763-769
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• 2018

In this research, in order to improve the heat retention of greenhouse, comparative analysis of the heat flux of the marketed multi-later insulating curtain was carried out. Experiments is conducted by fabricating a test apparatus for investigating the heat flux characteristics. The multi-later insulating curtain used for the experiment was compared using the P, N, S, U and T company, which are commercially available, and the heat flux due to temperature difference between the experimental apparatus and the outside was compared and analyzed. When the internal temperature of the experimental result is the maximum temperature $60^{\circ}C$, the heat flux of multi-later insulating curtain is T Co.($73.1W/m^2$) > S Co.($119.5W/m^2$) > U Co.($155W/m^2$) > N Co.($163.1W/m^2$) > P Co.($177.7W/m^2$). The heat flux means the quantity of heat passing through the unit time per unit area, and the higher the numerical value, the higher the quantity of heat passing through the multi-layer insulating curtain. This can be determined that high heat fluxes produce low heat resistance. Further, it has been found that the weight of the insulating curtain is largely unrelated to the heat insulating property, and the heat insulating curtain having a thickness containing a high internal air layer is excellent in the heat insulating property. In the future when manufacturing a heat insulating curtain, It is judged that it is desirable to manufacture a combination of heat insulating materials that contain a high internal air layer content and that can maintain the air layer even for long-term use while minimizing the volume.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.878-881
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• 2001

In this paper, we analyzed the characteristics of insulating material with ELB(earth leakage circuit breaker) through tracking experiment and the study was carried out three different types of samples. The tracking is breakdown phenomenon of material surface that is generated on the organic insulating material. The test method applied IEC publication 587. The result of the sample breakdown by tracking was carbonized and resistance of between the electrodes is approximately 300$\Omega$. In the result of DSC analysis, the caloric peak was detected before 100$^{\circ}C$ in product of tracking. It appeared weight loss of 10.87% at 537$^{\circ}C$ on TGA. IR spectrum analysis showed carbon-hydrogen(C-H)bond on molecular structure that is the sample of tracking.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.216-218
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• 1993

XLPE cable accessories are mainly consisted by the combination of various insulating materials such as XLPE cable insulation, rubber, epoxy, etc. It is important to investigate the dielectric and breakdown characteristics of the interfaces between various insulating materials. In this paper, by testing and measuring the breakdown strength, dissipation factor, volume and surface resistance and conduction current of specimens, we report the dielectric and breakdown characteristics of interfaces between various insulating materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.147-151
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• 1994

In order to investigate the dielectric characteristic insulating oil is chosen insulating oil for electric cable, and experiment is performed in the temperature range of 30∼120[$^{\circ}C$] and frequency range of 30∼1${\times}$10$\^$6/[㎐]. As a result, the observed linear decrease in tan $\delta$ value at the low frequency range is due to the influence of frequency, whereas the increase in tan $\delta$ value at high frequency range is contributed by the electrode's resistance and dielectric loss. The dipole moment and activation energy of specimen are obtained 1.22(debye) and 12.75∼18.66[㎉/㏖e] of high temperature region, 15.68 ∼ 20.6[㎉/㏖e] of low temperature region respectively.