• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.2
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• pp.133-140
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• 2002

This paper aims to investigate the effect of silicone oils as processing agent affecting the loss and recovery of hydrophobicity. The recovery of hydrophobicity was evaluated by the measurement of the surface electrical resistivity and the contact angle on the SIR surface. Two kinds of silicone oils (1 and 2) having different molecular weight were selected under a consideration of hydrophobicity and processability. SIR specimens were exposed to corona discharges in air and the specimens were analyzed with contact angle and surface resistance measurements. It was observed that the contact angle and the surface resistivity of SIR increase gradually with testing time. The fast recovery of hydrophobicity of SIR, expressed by the increment of contact angle and surface resistivity, was showed in SIR2 containing silicone oil 2.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.128-129
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• 2007

Electrochemical method 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.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1265-1266
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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.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.114-116
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• 2003

The multi function sprayed coating is used for direct-heating, wear resistance and high bonding strength. The merits of surface direct-heating coatings are short warming time, low power consumption and better wear resistance that can be used in many organization parts. In this study, the surface direct-heating and wear resistance can be improved by spraying the proper materials on the surface $Al_2$O$_3$40%TiO$_2$ powder and Ni-20%Cr powder that had the properties of conduction and high wear resistivity are used in order to improve wear resistance, electrical properties and bonding strength.

• Journal of the Korean institute of surface engineering
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• v.51 no.2
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• pp.116-125
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• 2018

Aluminum-doped zinc oxide (AZO) is a commonly used material for the front contact layer of chalcopyrite $CuInGaSe_2$ (CIGS) based thin film solar cells since it satisfies the requisite optical and electrical properties with low cost and abundant elemental availability. Low-resistivity and high-transmission front contacts have been developed for high-performance CIGS solar cells, and nearly meet the required performance. However, the durability of the cell especially for the corrosion resistance of AZO films has not been studied intensively. In this work, AZO films were prepared on Corning glass 7059 substrates by radio frequency magnetron sputtering depending on the hydrogen content. The electrical and optical properties and electrochemical corrosion resistance of the AZO films were evaluated as a function of the hydrogen content. With increasing hydrogen content to 6 wt%, the crystallinity, crystal size, and surface roughness of the films increased, and the resistivity decreased with increased carrier concentration, Hall mobility, oxygen vacancies, and $Zn(OH)_2$ binding on the AZO surface. At a hydrogen content of 6 wt%, the corrosion resistance was also relatively high with less columnar morphology, shallow pore channels, and lower grain boundary angles.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.427-430
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• 2002

This paper presents on contamination performance of polymeric outdoor insulator with different contaminant accumulation. The ESDD (equivalent salt deposit density), tracking resistance and clean-fog test were performed to investigate the characteristics of contamination performance on polymeric outdoor insulator. Furthermore, we evaluated together with the porcelain samples for its comparison. It is found that ESDD of polymeric and porcelain insulator depends on the installation position. This surface accumulation of contaminant lead to the loss of surface hydrophobicity, expecially upper shed part of polymeric insulator. In addition, the effect of an artificial contaminant on the tracking resistance by inclined-plane method and leakage suppression ability under clean fog was surveyed. The time of tracking failure did not appear to change significantly with a much contaminant accumulation, while leakage current under clean-fog increased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.6
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• pp.431-434
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• 2012

In this paper, heat-releasing sheets made of AlN powder and acryl binder as thermoset were prepared using tape casting method. The crystal structure and morphology, the thermal properties as nonvolatile solid content and thermal conductivity, and the surface resistance of heat-releasing sheet were measured by using X-ray diffractometer, field emission-scanning electron microscopy, thermo gravimetric analyzer and laser flash instrument, and surface resistance meter. It was proved that thermal conductivity is greatly affected by the content of binder in heat-releasing sheet. Superior thermal conductivity above 3.5 W/mK and suface resistance were obtained at heat-releasing sheet with above 90% of AlN powder.

• Journal of the Korean institute of surface engineering
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• v.38 no.2
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• pp.55-59
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• 2005

ITO/Ni/ITO thin films were deposited on the PET by RF magnetron sputtering. Dependance of the process parameters such as deposition pressure, positions of Ni layer, on the transmittance, reflectance and sheet resistance of ITO/Ni/ITO film were investigated. When the Ni layer is placed at the center of ITO and deposition pressure is low, ITO/Ni/ITO films showed better optical and electrical properties. At these conditions, the transmittance, reflectance and sheet resistance of the ITO film were $90\%,\;0.38\%$ and $185\Omega/\Box$ respectively.

• Journal of the Korean institute of surface engineering
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• v.37 no.3
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• pp.158-163
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• 2004

ITO thin film was deposited on the glass by RF magnetron sputtering. Dependance of the process parameters such as thickness, target-to-substrate distance, substrate temperature and oxygen partial pressure on the transmittance and electrical resistance of ITO film were investigated. The deposition conditions for getting better optical and electrical ITO characteristics were the 1800-$2300\AA$ thickness, 65mm substrate-to-target distance, $350^{\circ}C$ substrate temperature and 8% oxygen partial pressure. At these conditions, the transmittance and sheet resistance of the ITO film were 83.3% and 77.86Ω/$\square$, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.558-559
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• 2005

Recently, polymer insulators that are used for high voltage applications have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. During outdoor service of polymer insulators, the surface of the insulating material is frequently subjected to moisture and contamination that lead to dry band arcing. Their tracking resistance, erosion resistance, end sealing and shed design are very important because dry band arcing causes degradation of polymer surface. In this paper, the tracking property of polymer suspension insulator for power transmission is investigated with CEA tracking wheel test. The diagnosis of insulator sample in tracking test has been analyzed by leakage current, STRI Guide, SEM, FTIR and thermal image.