• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1453-1456
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• 2009

Transparent sol-gel hybrid dielectric material (hybrimer) coating films were fabricated by spin coating and photo or thermal curing of sol-gel derived oligosiloxane resins. Hybrimer coating films are suitable as the passivation layer of TFT in AMLCD due to low dielectric constant, small loss tangent, low leakage current density, high transmittance and thermal stability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.477-480
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• 1998

Sol-gel processing, which started some decades back as a laboratory curiosity, has proved to be a powerful and versatile technique for the synthesis of materials. The utility of the sol-gel method for producing glass and ceramic materials in the form of powders, fibers, thin films and bulk shapes with high purity, functional microstructures and potentially high chemical homogeneity at relatively low temperature (compared to conventional processing) has been discussed.

• Membrane Journal
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• v.19 no.1
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• pp.19-24
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• 2009

Sol-gel process is relatively simple, easy to use, cheap to install, and results in thin coating layers with superior physical and gas barrier properties. Films coated by the sol-gel process can be used as insulating films or packaging films for foods, chemicals, drugs, and beverages, etc. In this study, alumina sol was synthesized from aluminum isopropoxide and silane coupling agent was added to make coating solutions. In addition, biaxially oriented polypropylene (BOPP) was coated using several alumina sol solutions and their oxygen permeabilities were measured. The experimental results indicate that in the best case, the oxygen permeability of coated film was reduced by 85% compared to that of pure BOPP.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.4
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• pp.315-320
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• 2012

In general, a photoelectrode in DSSC(dye sensitized solar cell) are fabricated by using the $TiO_2$ (Titanium dioxide) to realize high efficiency and the efficiency of DSSC is affected by the size, the shape and the property of $TiO_2$. We synthesized the crystalline $TiO_2$ by sol-gel method. In spite of many merits, only weakness for the sol-gel method is taking many process times. To solve this problem, we reduced the fabricating processes. The reduced process is the making process that is $TiO_2$ sol to $TiO_2$ powder with including of two heat treatment and two mixing. We could simplify the process by preparing $TiO_2$ sol to $TiO_2$ paste directly. As a result, DSSC fabrication process is simplified and we have obtained the efficiency best result 3.88% with $V_{OC}$=0.71 V, $J_{SC}=8.70\;mA/cm^{-2}$, and FF=62.37%, respectively.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.7
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• pp.349-353
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• 2006

[ $TiO_2-Nb_2O_5$ ] sol was prepared using sol-gel method. Crystalline properties of gel powder changed from rutile phase to anatase phase with increasing $Nb_2O_5$ additives at $800^{\circ}C$, while they retained rutile phase regardless of $Nb_2O_5$ additives at $900^{\circ}C,\;1,000^{\circ}C$. They retained amorphous phase from $50^{\circ}C\;to\;400^{\circ}C$, retained anatase phase from $500^{\circ}C\;to\;600^{\circ}C$ and had rutile phase over $700^{\circ}C$ at 1mole% $Nb_2O_5$ additive. After $TiO_2-Nb_2O_5$ sol retained low viscosity with normal chain structure for a long time, its viscosity increased fast with network structure. DTA properties of gel powder had endothermic reaction due to evaporation of propanol and water about $78^{\circ}C$, had exothermic reaction due to propanol combustion about $290^{\circ}C$ and had exothermic reaction due to changing of $TiO_2$ phase about $640^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.37 no.5
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• pp.425-431
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• 2000

Cobalt ferrite thin films on Corming glass substrate were fabricated by a sol-gel method. Cobalt ferrite thin films with the grain size of 20-35 nm and thickness of 50nm were obtained. Rapid thermal annealing (RTA) and Annealing processes were adopted for comparison of characteristics of the films. Coercivity values were changed with thermal condition and magnetization values were increased as a function of soaking time. With prolonged soaking time, however, it was decreased because of the diffusion of cations from the glass substrate. The RTA process in preparation of cobalt ferrite thin film was the effective way to prevent and to form a single spinel phase in reduced soaking time. The film heated at 600$^{\circ}C$ for 30 minutes by RTA had coercivity of 2,600 Oe, saturation magnetization 460 emu/㎤, and Mr$.$$\delta$ of 1.43 memu/$\textrm{cm}^2$.

• Journal of Information Display
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• v.9 no.3
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• pp.8-11
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• 2008

A novel non-alkoxide sol-gel process for synthesizing Ga-doped ZnO thin film on glass was derived for possible use as a transparent electrode in flat-panel displays, using zinc acetate dehydrate as the starting material. The structural and electrical properties of thin films have been characterized as functions of Ga addition and post-heat-treatments. Their carrier density, Hall mobility, and optical transmittance were measured and discussed herein to explain the characteristics of the sol-gel-derived Ga-doped ZnO thin film on glass.

• Journal of the Korean Ceramic Society
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• v.40 no.4
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• pp.380-384
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• 2003

The effects of the mole concentrations of precursor solution on the microstructure and dielectric properties of sol-gel deposited $Ba_{0.85}$S $r_{0.15}$Ti $O_3$(BST) thin films have been investigated. The films were of single perovskite phase with strong (100) preferred orientation when grown on LaNi0$_3$ buffered Pt/Ti/ $SiO_2$Si substrates using a diluted precursor solution. Variation of the precursor solution concentration resulted in a different microstructure and, in turn, affected the tunability of the sol-gel deposited films. It was observed that leakage currents increased asymmetrically for the negative and positive bias voltage with decreasing thickness. Overall results suggest that those BST films have acceptable properties f3r applications as room-temperature tunable elements.

• Journal of the Korean Ceramic Society
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• v.24 no.5
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• pp.423-430
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• 1987

Characteristics of Al2O3-ZrO2 powders prepared by sol-gel process and their sintering behavior were investigated as a function of calcination temperature. The sol-gel processed powders were calcined at 800, 900, 1000, 1100, 1200$^{\circ}C$, and analyzed by X-ray diffraction technique. Pore size and distribution of green compact of the calcined powders were measured by mercury porosimeter. It is suggested that the optimal temperature of calcination for the sintering of Al2O3-ZrO2 powder prepared by sol-gel process is 1100$^{\circ}C$. In the Al2O3-17vol.% ZrO2 sintered specimen, which was sintered at 1600$^{\circ}C$ for 2hrs in air, 69vol.% tetragonal phse existed.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.191-191
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• 2003

가시광선영역에서 높은 광학적 투명도를 갖는 n-type 반도체인 ZnO 박막은 넓은 범위에서 응용되고 있다. 현재 ZnO 박막의 특성 향상을 위하여 여러 원소(Al, Ga)의 도핑을 시도하고 있다. 특히 Al-doped ZnO 박막은 sol-gel dip coating에 의해서도 높은 전기전도도와 투과율로 활발히 연구되고 있다 본 논문에서는 여러 도핑농도를 갖는 Al-doped ZnO 박막이 sol-gel dip coating법에 의해 준비되었다. Al-doped ZnO 박막은 zinc acetate [Zn($CH_3$COO$_2$)ㆍ2$H_2O$] powder 와 여러 도핑농도를 갖는 aluminum nitrate (Al(NO$_3$)$_3$ㆍ9$H_2O$) powder를 알코올에 용해하여 $H_2O$, Ethylene glycol, Ethylene diamine 등을 첨가하여 제조하였다 XRD와 SEM (Scanning electron microscope)이 막의 상형성 분석을 위해 이용되었으며, 가시광선 영역 투과율(UV/VIS spectrophotometer)과 표면전기저항(four point probe)이 주요 특성으로 분석되었다.