• Textile Coloration and Finishing
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• v.6 no.1
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• pp.62-70
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• 1994

Silk fibroin was dissolved in 9.3 M LiBr aqueous solution at 4$0^{\circ}C$ for 1 hour. The dissolved silk fibroin was regenerated by casting the dialyzed solution into the membrane. The freshly prepared silk fibroin membrane was soluble in water and was. mainly consisted of random coil conformation. By the treatments in saturated water vapor at 3$0^{\circ}C$ and in 75% ethanolic aqueous solution (V/V), the insoluble membranes were obtained and the structure and morphology of those were investigated for the structure by means of X-ray diffraction analysis, infrared spectroscopy, thermal analysis. Rheovibron and scanning electron micrograph. Silk II type crystals were obtained by treating amorphous silk fibroin membrane in the random coil conformtion with 75% ethanol solution(V/V). Crystallization to silk II type crystals occured even after a few minutes, and a large number of silk II type crystals were formed after 30 mins. On the other and, the membrane treated in saturated water vapor was composed of the mixtures of silk I and silk II type crystals. A large number of silk I and silk II type crystals were formed after 24 hours. The micro brownian motion in the amorphous regions of silk fibroin membrane started at about 175~185$^{\circ}C$. $\alpha$ dispersion appeared at about 20$0^{\circ}C$ in the amorphous membrane, and at about 22$0^{\circ}C$ in the crystalline membrane. The crystallization of random coil conformation to silkII type crystals occured at about 215$^{\circ}C$. The surface, bottom and cross-section of the membranes were observed by scanning electrom microscope. Fine forms alike spherulites appeared at the surface of crystalline membrane.

• Journal of the Korean institute of surface engineering
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• v.41 no.5
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• pp.220-225
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• 2008

In this study, two kinds of Fe-based bulk metallic glasses (BMG) powder were built-up through atmospheric plasma spray (APS) technique. The microstructure of two coatings was analyzed through X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Crystallization and oxidation in coatings were affected by chemical composition and initial powder size. Then, both of them influenced the tribological property.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05b
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• pp.82-85
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• 2002

In recent years, the tantalum nitride(TaN) thin-film has been developed for the electronic resistor and capacitor. In this papers, this study presents the surface profile and sheet-resistance property relationship of reactive-sputtered TaN thin film resistor processed by buffer of Ti and Cr on alumina substrate. The TCR properties of the TaN films were discussed in terms of reactive gas ratio, ratio of nitrogen, crystallization and thin films surface morphology due to annealing temperature. It is clear that the TaN thin-films resistor electrical properties are low TCR related with it's buffer layer condition. Ti buffer layer thin film resistor having a good thermal stability and lower TCR properties then Cr buffer expected for the application to the dielectric material of passive component.

• Journal of the Korean Ceramic Society
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• v.33 no.12
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• pp.1380-1386
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• 1996

The effects of urea addition and reaction conditions were examined in the prepareation of zirconia coated SiC whiskers through surface precipitation taking place during high-temperature aging of Zr(SO4)2 solutions containing the whiskers. More dense zirconia-hydrate was precipitated on the surfaces of the whiskers in the presence of urea. The ratio of the concentration of Zr(SO4)2 to the amount of added whiskers was the most important factor to confine the precipitation of zirconia-hydrate only at the surfaces of the whiskers The from of the coating layers was unchanged after heat-treatment leading to the dehydration and crystallization of the layers.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.278-279
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• 2015

CIGS 전구체는 각각 DC와 RF power로 셀레늄(Se)이 포함된 CuSe 타겟과 $(In,Ga)Se_2$ 타겟을 이용하여 스퍼터링 기법으로 증착한 후에 고속결정화 특성을 위해 전자빔을 조사하였다. 전자빔의 가속 전자의 강도(DC power)는 2.5~3.5keV로 조정하고 조사시간은 300초, RF power는 200W로 고정하였다. SEM image에서 전구체의 두께가 가속 전자의 강도에 따라 100~200nm의 손실됨을 확인할 수 있었다. XRD data 결과에서 3keV에서 조사된 샘플에서 가장 높은 (112) 피크의 특정 배양성을 보여 높은 결정화특성을 나타내었다. 조성비간의 변화를 보기 위해 XRF data 분석결과 전구체와 샘플간의 조성비의 차이는 그리 크지 않으나 I/III 족 비가 3 keV에서 가장 이상적인 비율이라 알려져 있는 1.0을 보였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.194-195
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• 2012

대향 타겟 스퍼터링법 (Facing Targets Sputtering)을 이용하여 저온 공정에서 ZnO 박막을 증착하였다. 이 실험에서 두 개의 타겟의 거리를 70nm로 고정하고 박막의 증착두께를 150nm로 정하였다. 인가전압을 변수로 하였을 경우 ZnO 박막의 방향성과 결정성을 XRD로 측정하고 분석하였고 OES로 플라즈마 진단을 하였다. 그 결과 인가전압의 증가에 따라 결정성은 증가하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.162-163
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• 2014

Aluminum anodizing is a technique that can be formed pores well aligned various diameters. We were prepared CNFs using the polymer as carbon source using the AAO as a template. CNFs can be heat treated at $1400^{\circ}C$ and became soft carbon. It showed electrochemical behavior by Crystallization. In this experiment, I was observing the behavior as a anode material for LIC of CNFs having different diameters.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.117-117
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• 2014

Thin $ZrO_2/Al_2O_3$ films were deposited on a tool steel substrate using Zr and Al cathodes in a cathodic arc plasma deposition system (CAPD), and then oxidized at $600-900^{\circ}C$ in air for up to 50 h. They effectively suppressed the oxidation of the substrate up to $800^{\circ}C$ by acting as a barrier layer against the outward diffusion of the substrate elements and inward diffusion of oxygen. However, rapid oxidation occurred at $900^{\circ}C$ due mainly to the increased diffusion and subsequent oxidation of steel as well as the crystallization of amorphous $Al_2O__3$.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1588-1590
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• 1997

The viewing angle characteristics of amorphous(a)-twisted nematic(TN)-liquid crystal display (LCD) on poly(vinyl)cinnamate (PVC) surfaces with photo polymerrization were investigated. It was found that the threshold voltage increases with increasing the polymerization of PVC surfaces. That the domain size of a-TN-LCD is affected by the surface crystallization with increasing the photo polymerization of the photo-alignment film. We observed that the viewing angle of a-TN-LCD increased with increasing the photo polymerization on PVC surfaces. Finally, we consider that the viewing angle of a-TN-LCD on PVC surfaces is large compared to a-TN-LCD on polyimide(PI) surface.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1239-1242
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• 1994

We have characterized XeCl excimer-laser-induced crystallization of thin amorphous silicon films deposited by PECVD (${\alpha}-Si:H$) and LPCVD(${\alpha}-Si$). The electrical and optical properties and surface roughness of crystallized thin films have been measured. The dc conductivities, crystallinity and surface roughness of the films increased as the laser energy density and shot density were increased. Also, we have investigated the effects of 2-step annealing employing SPC and ELA. The properties of 2-step annealed films were better than those of films annealed by ELA only.