• Korean Journal of Materials Research
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• v.27 no.11
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• pp.577-582
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• 2017

Self-cleaning and photocatalytic $TiO_2$ thin films were prepared by a facile sol-gel method followed by spin coating using peroxo titanic acid as a precursor. The as-prepared thin films were heated at low temperature($110^{\circ}C$) and high temperature ($400^{\circ}C$). Thin films were characterized by X-ray diffraction(XRD), Field-emission scanning electron microscopy(FESEM), UV-Visible spectroscopy and water contact angle measurement. XRD analysis confirms the low crystallinity of thin films prepared at low temperature, while crystalline anatase phase was found the for high temperature thin film. The photocatalytic activity of thin films was studied by the photocatalytic degradation of methylene blue dye solution. Self-cleaning and photocatalytic performance of both low and high temperature thin films were compared.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.847-850
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• 2008

Three thermally stable red dyes of azo, quinacridone and perylene derivatives were synthesized and dye-based color filters were manufactured for liquid crystal display. Aggregation behavior of the dyes and their spectral property in film state were investigated by concentration dependent spectroscopy and field emission scanning electron microscopy (FE-SEM). These dyes have remarkable difference on their aggregation behavior in film state. Such difference of aggregation behavior affects the spectral property of the film, and it can cause decreasing the transmittance of dye-based color filters.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1351-1354
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• 2006

In this paper, we study the effect of substrate temperature on property of Ga doped ZnO (GZO) thin film for transparent conductive oxide (TCO).GZO thin films have been deposited on corning glass 1737 by D.C. magnetron sputtering. We investigated the structural and electrical properties of GZO films using the X-Ray Diffractometer(XRD), Field Emission Scanning Electron Microscopy(FESEM) and 4-points probe .

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.281-281
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• 2010

In this study, ZnO nanorod arrays are grown on organic substrates by hydrothermal method which requires a low temperature, simple process, and no vacuum. The structure properties of ZnO nanorods were examined by field emission scanning electron microscopy and X-ray diffraction. To detect the optical transmission, ultraviolet visible spectrophotometer was also used. From results, the ZnO nanorods were grown the horizontal growth on the organic substrates had the length of over $10\;{\mu}m$. After deposition of ZnO seed layer, the ZnO nanorod arrays had uniformity orientation and length.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1069-1072
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• 2003

Germane-sillicide phase formation on S $i_{0.25}$G $e_{0.75}$ with Ni 100$\square$, Co 10$\square$/Ni 100$\square$ and Ni 50$\square$/Co 10$\square$/Ni 50$\square$ layer was studied by sheet resistance and Field Emission Scanning Electron Microscopy(FESEM). Thermal stability of nickel germane-silicide is found to be improved by sputtering Ni/Co/Ni on the SiGe. After annealing at 600, 650, $700^{\circ}C$, 30min., the nickel germane-silicide formed by Ni 50$\square$/Co 10$\square$/Ni 50$\square$ layer achieved a sheet resistance less than 17ohms/sq.(almost the same to the value before furnace annealing for 30min.) , while the process of the other two ways result in high sheet resistance and even sheet resistance fail due to Ge segregation.ion.

• Animal cells and systems
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• v.13 no.2
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• pp.153-160
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• 2009

The fine structural characteristics of the silk spinning apparatus in the titanoecid spiders Nurscia albofasciata have been examined by the field emission scanning electron microscopy (FESEM). This titanoecid spiders have a pair of medially divided cribella just in front of the anterior spinnerets, and the surface of the cribellum is covered by hundred of tiny spigots which produce numerous cribellate silk fibrils. The cribellar silks are produced from the spigots of the sieve-like prate. and considered as a quite different sort of catching silk with dry-adhesive properties. The other types of the silk spigots were identified as follows: ampullate, pyriform and aciniform glands. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another 1-2 pairs of minor ampullate glands supply the middle spinnerets. In addition, the pyriform glands send ductules to the anterior spinnerets, and two kinds of the aciniform spigots feed silk into the middle (A type) and the posterior spinnerets (both of A & B types), respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.6
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• pp.462-466
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• 2012

In this paper, heat-releasing composite sheets made of AlN, graphite, Al powder and acryl binder as thermoset were prepared using tape casting method. The crystal structure, morphology, thermal conductivity of heat-releasing composite sheet were measured by using X-ray diffractometer, field emission-scanning electron microscopy and laser flash instrument. It was found thermal conductivity of sheet was decided by solid content, composition including AlN, graphite, Al in heat-releasing composite sheets. As a result, 4.56 W/mK of thermal conductivity could be obtained by using LFA 447.

• 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.

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.123-126
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• 2011

Titanium dioxide ($TiO_2$) thin films were deposited by the sol-gel method with a surfactant-assisted mechanism. Its application for dye-sensitized solar cells (DSSCs) was investigated. Brunauer-Emmett-Teller, X-ray diffraction and field emission scanning electron microscopy techniques were used to characterize the surface characteristics of thin films. Photovoltaic-current density measurements were performed to determine the photoelectrochemical properties of the thin films and the performance of DSSCs. Energy conversion efficiency of about 6.1% was achieved for cells with conductive glass under illumination with AM 1.5 (100 $mWcm^{-2}$) simulated sunlight. Investigation showed higher photo-energy conversion efficiency for mesoporous $TiO_2$ nanocrystalline films used in DSSCs relative to commercially available Degussa P25 films.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.475-475
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• 2014

Dye sensitized solar cells (DSSCs) are regarded as potential inexpensive alternatives to conventional solid-state devices. The flexible version, employing conductive-plastic-film substrates, is appealing for commercialization of DSSCs because it not only reduces the weight and cost of the device but also extends their applications. However, the need for high temperature does not permit the use of plastic-film substrate. So, development of low-temperature methods is therefore realization of flexible DSSCs. In this work, the electrophoretic deposition combined with hydrothermal treatment was employed to prepare nanocrystalline $TiO_2$ thin film at low temperature. We confirmed the prepared $TiO_2$ thin films with different voltages and deposition times in the electrophoretic deposition process. Properties of the $TiO_2$ films were investigated by various analysis method such as X-ray diffraction, field emission scanning electron microscopy (FESEM) and UV-visible spectrophotometer.