• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.428-430
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• 2008

Dye-sensitized solar cell has many internal resistant components such as Pt counter electrode, $TiO_2$/dye/electrolyte, charge diffusion, sheet resistance of TCO. Among these, the resistance about the counter electrode can be reduced by increasing the roughness factor of Pt counter electrode. This causes the increase of fill factor and improvement of efficiency. And the amount of light reflection on the counter electrode also increases as the roughness factor goes up. In our experiment, we suggest a new deposition structure of Pt thin film that is a stepped-type structure. The more step lines are in the counter electrode, the more roughness factor is. As a result, we get the improvement of fill factor and efficiency by controlling the roughness factor of counter electrode.

• Journal of Welding and Joining
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• v.26 no.2
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• pp.75-84
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• 2008

With the development of surface roughness textured steel for automotive body-in-white assemble, one of key issues is to understand the role of the surface roughness in textured steel sheets. To investigate effect of surface roughness on weldability in prepared steels, electrode force was varied. Steel sheets (T-H) with high surface roughness ($Ra\;=\;1.94\;{\mu}m$) reduced electrode life. It was attributed to the higher contact resistance at the electrode-sheet interface in the presence of the high surface roughness. The increased electrode diameter decreased current density, therefore reducing weld electrode life due to small weld button size. When an increased electrode force was used, a significant increase in the electrode life was observed in welding of high surface roughness steel sheet. This study suggested that contact resistance at the electrode-sheet interface was the dominant factor, as compared to the sheet-sheet interface for determining electrode life in welding of surface roughness textured steel.

• Journal of the Semiconductor & Display Technology
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• v.18 no.4
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• pp.1-5
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• 2019

This study has been focused on properties of surface technology for large diameter upper electrode using in high density plasma process as like semi-conductor manufacturing process. The experimental studies have been carried out to get mirror surface for upper electrode. For a formation of high surface quality upper electrode, single crystal silicon upper electrode has been mechanical and chemical machining worked. Mechanical machining work of the upper electrode is carried out with varying mesh type using diamond wheel. In case of chemical machining work, upper electrode surface roughness was observed to be strongly dependent upon the etchant. The different surface roughness characteristics were observed according to etchant. The machining result of the surface roughness and surface morphology have been analyzed by use of surface roughness tester, laser microscope and ICP-MS.

• Korean Journal of Metals and Materials
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• v.46 no.8
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• pp.495-505
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• 2008

With the high proportion of zinc coated steels in body-in-white assembly, newly developed surface roughness textured galvannealed steel sheets have been introduced. In this study, zinc coated and surface roughness textured steel sheets were welded by resistance spot welding to investigate its weldability including electrode wear test. Based on the results of tensile-shear test, nugget diameter changes, and electrode tip growth test, it was clear that both surface roughness textured steels (GA-T and GA-E) showed good weldability. Also, there was no large difference in weldability and electrode wear behavior between GA-T and GA-E steels which have different surface roughness morphology. An analysis of electrode degradation showed Fe and Zn penetration through the electrode tip surface at 2400 welds reached $55{\sim}60{\mu}m$ and $75{\sim}80{\mu}m$, respectively. Therefore, there is no significant effect of surface roughness morphology on spot weldability of surface roughness textured galvannealed steel sheets. However, slight difference in thickness of alloying layers existing on electrode tip was found between GA-T and GA-E steels.

• Journal of the Korean Electrochemical Society
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• v.3 no.2
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• pp.104-108
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• 2000

It is very important to know the real roughness of electrode surface in electrochemistry. But it is impossible to know absolute roughness of electrode surface for various reasons. In this work, we compared the roughnesses of polycrystalline gold electrode often used in electrochemistry calculated from the images of scanning tunneling microscopy (STM) and cyclic voltammetry with those of Au (111) and HOPG. The roughness of polycrystalline gold calculated from STM image was $1.1(\pm0.1)$, that from adsorption-desorption of oxygen was $2.4(\pm0.7)$ and that from adsorption of N-docosyl-N'-methyl viologen was $1.6(\pm0.1)$.

• Journal of the Semiconductor & Display Technology
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• v.20 no.1
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• pp.59-63
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• 2021

Upper electrode is one of core parts using plasma etching process at semiconductor. The purpose of this study is to analyze effects of cutting conditions for mechanical machining of silicon upper electrode. For this research, surface roughness of machined workpiece and depth of damage inside of silicon electrode are experimented and analyzed and different values of feed rate and depth of cut are applied for the experiments. From these experiments, it is verified that the surface roughness and internal damaged layer get worse according to take more fast feed rate. In conclusion, cutting condition is very important factor for machining. Results of this study can use to develop various parts which are made from single crystal silicon and affect various benefits to the semiconductor industry for better productivity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.569-570
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• 2006

In this study, the characteristics of Electrical Discharge Machining (EDM) with the electrode materials were investigated. EDM experiments have been carried out on electrodes with eight different copper-based and graphite-based materials. From the results, the copper-based electrodes showed excellent surface roughness than the graphite-based electrodes. But graphite based electrodes have advantages in economic aspects.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.291-292
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• 2010

• 전기의세계
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• v.28 no.11
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• pp.33-36
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• 1979

In a uniform field, when an electrode with a hemispherical protrusion is set in atmosphere, by applying the streamer breakdown criterion and the surface roughness factor, the effect of field distortion due to electrode surface roughness on breakdown is investigated theoretically. A quantitative relation between the threshold of breakdown and the air pressure times the heigh of protrusion is derived by the aid of a computor and the results are compared with that of SF$_{6}$./.

• Journal of the Korean Ceramic Society
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• v.34 no.11
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• pp.1121-1128
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• 1997

In this study, the Ar plasma treatment was used to improve the surface roughness of Poly-Si1-xGex thin film deposited by RTCVD. The surface roughness and the resistivity of Si1-xGex thin film were investigated with variation of Ar plasma treatment parameters (electrode distance, working pressure, time, substrate temperature and R.F power). When the Ar plasma treatment was used, the cluster size decreased by the surface etching effect due to the increasing surface collision energy of particles (ion, neutral atom) in plasma under the conditions of decreasing electrode distance and increasing pressure, time, temperature, and R. F power. Although the surface roughness value decreased by the reduction of the cluster size due to surface etching effect, however, the resistivity increased. This may be due to the surface damage caused by the increasing surface collision energy. It was concluded that the surface roughness could be improved by the Ar plasma treatment, while the resistivity was increased by the surface damage on the substrate.