• Journal of the Semiconductor & Display Technology
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• v.5 no.3 s.16
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• pp.17-21
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• 2006

The oxygen barrier films were formed on poly(ethylene terephthalate) (PET) substrate by a sol-gel process using aminoalkoxysilanes. The coating layers were characterized by FT-IR and SEM. The oxygen permeability coefficients of coating films were measured by variable volume method, and then the influences of solvent ratio in sol and film drying temperature on the oxygen barrier properties were investigated. The aminoalkoxysilane coating films exhibited much higher oxygen barrier properties than PET film. The oxygen permeability coefficient of the film coated with each of APTEOS and APTMOS was measured to be $2.96{\times}10^{-6}$ and $3.05{\times}10^{-5}\;GPU$, respectively, while that of PET film was $1.16{\times}10^{-4}\;GPU$.

• The Korean Journal of Ceramics
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• v.6 no.4
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• pp.359-363
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• 2000

Reduced nicotinamide adenine dinucleotide (NADH) was encapsulated in transparent porous sol-gel silicate gels using by different organoalkoxysilane precursor. Characteristics optical absorption and fluorescence of NADH in the gels were examined with depending on NADH concentration and compared. Optical absorption in the aminopropyltrimethoxysilane (APTMS) gel is highest and remains constant during aging the gel. Thus, it is found that NADH in the APTMS gel is most stable and activated. On the other hand, methyltriethoxysilane (MTES) gel presents the lowest optical absorption diminishing with aging the gel. Measurable increase of fluorescence with raising the NADH concentration is observed except for the APTMS gel due to its solubility in the buffer during fluorescence measurement.

• Journal of the Korean Ceramic Society
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• v.32 no.1
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• pp.57-62
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• 1995

The coating condition of reproducible anti-reflective coating film and the light transmittance characteristics of the prepared anti-reflective coating glass were investigated as a study for the preparation of single-layer anti-reflective coating glasss. In case of coating with the sol in which the solvent was substituted with the ethanol with the addition of 0.1 mol HNO3, the coated glass showed the minimum value of the refractive index of 1.464, light transmittance of 94.2% at 550nm standard wavelength which is 3.2% higher than that of the parent glass, and the reflectance in the entire wave range of visible light. The refractive index represented its minimum at the sol concentration of 1.0 mol per 100mols of water and the higher the sol concentration, the higher the refractive index, resulting in the decrease of the light transmitance. The production condition of the reproducible anti-reflective coating on glass with the maximum transmittance of 94.2% was 4cm/min of withdrawal speed, 40$0^{\circ}C$ and 1 hour of heat treatment temperature and time, resulting in the film thickness of 94nm.

• Corrosion Science and Technology
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• v.22 no.6
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• pp.447-456
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• 2023

In this work, we performed a comparative study examining two coatings on Ti Gr.1 for use in fuel cell bipolar plates. The coatings consisted of carbon black as the conductor along with acrylic polymer and Ti Sol-Gel binder as the binder. Ti Sol-Gel that had precipitated as TiO₂ in areas impregnated between carbon black gaps, thereby acting as a binder for carbon black and serving as a polymer coating. Neither of the coatings peeled off during the 90° bend test to check formability. The contact resistance of the TiO₂ coating was found to be lower than that of the polymer binder coating. Moreover, due to coating shrinkage (denser) that occurred during the heat treatment process, the TiO₂ binder coating showed almost the same level of corrosion resistance, as measured by potentiostatic and EIS tests, despite being thinner than the polymer coating. However, both the polymer binder coating and the TiO₂ binder coating had many pores and irregularities internally (around 10 ~ 100 nm) and on the surface (0.1 ~ 2 ㎛). We considered that these pores and irregularities contributed to the lower corrosion resistance.

• The Journal of Engineering Research
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• v.6 no.1
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• pp.161-168
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• 2004

In the present study, a simple method was successfully used for hydroxyapatite coatings on Ti-6AL-4V substrates deposited by using a sol-gel derived precursor. Prior to hydroxyapatite coating the samples were micropolished (0.1 micron) and divided into three sets. The first set, were the micropolished samples kept as such. The second set were coated with titania sol and the third set was treated with 5M NaOH. After three repetitions of hydroxyapatite coating procedures on each set and heat treatment at $600^{\circ}C$, the formation of hydroxyapatite has been confirmed by XRD analyses and the substrate material was found to be oxidized with negligible amount of CaO in the coating. The SEM studies revealed surface morphology. Hydroxyapatite, calcined at $600^{\circ}C$, displaying a porous structure arisen from heating of the bulk

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.7
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• pp.1491-1496
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• 2005

We fabricated the $Pb_{0.72}La_{0.28}TiO_3$ (PLT(28)) thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of $100\%$ perovskite phase by drying at $350^{\circ}C$ after each coating and final annealing at $650^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the $Pt/Ti/SiO_2/Si$ substrate and its dielectric constant and leakage current density were measured as 936 and $1.1{\mu}A/cm^2$, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.865-868
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• 2005

We fabricated the $Pb_{0.72}La_{0.28}TiO_3 (PLT(28))$ thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of 100% perovskite phase by drying at 350$^{\circ}C$ after each coating and final annealing at 650$^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the Pt/Ti/SiO$_2$/Si substrate and its dielectric constant and leakage current density were measured as 936 and 1.1${\mu}$A/cm$^2$, respectively

• Journal of the Korean Ceramic Society
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• v.31 no.9
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• pp.1060-1068
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• 1994

Stable zirconia sol was prepared from zirconium butoxide Zr(OC4O9)4 as a precursor and ethylacetoacetate(EAcAc) or diethylene glycol(DEG) as a chelating agent under ambient agent under ambient atmosphere by Sol-Gel process. The sythesized sol was coated on 304 stainless steel substrate by dip coating, thereafter zirconia film could be obtained by heat-treatment at $600^{\circ}C$. The characteristics of coating film were determined by FT-IR, XRD, and ellipsometion peak represented Zr-O-Zr bonding of tetragonal phase was shown at 470cm-1. Crystallization of zirconia gel and film from amorphous state to tetragonal phase started at 40$0^{\circ}C$, and then transformed into monoclinic phase around $700^{\circ}C$. Zirconia film coated on 304 stainless steel substrate showed relatively low porosity of 16% when it was coated with 0.4M zirconia sol and thereafter heat-treated at 80$0^{\circ}C$ and the film was densified continuously up to 90$0^{\circ}C$. The zirconia film of 10 nm thick acted as a protective layer against oxidation up to $700^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.338-342
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• 2016

ZnO thin film co-doped with F and Al was prepared on a glass substrate via simple non-alkoxide sol-gel spin coating. For a fixed F concentration, the addition of Al co-dopant was shown to reduce the resistivity mainly due to an increase in electrical carrier density compared with ZnO doped with F only, especially after the second post-heat-treatment in a reducing environment. There was no effective positive contribution to the reduction in resistivity due to the mobility enhancement by the addition of Al co-dopant. Optical transmittance of the ZnO thin film co-doped with F and Al in the visible light domain was shown to be higher than that of the ZnO thin film doped with F only.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.189-189
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• 2003

WO$_3$ 박막은 H$^{+}$이온이나 Li$^{+}$ 이온과 반응하여 H$_2$WO$_4$나 Li$_{x}$WO$_{3+x}$의 화합물을 이루고 파란색을 나타내는 효과를 보인다. 이러한 효과를 전기변색 (electrochromic) 효과라 한다. 이러한 전기변색효과를 이용하여 건축물의 창문을 통하여 들어오는 태양에너지와 빛의 양을 조절하는 윈도우를 제작하려는 국가적인 프로젝트가 미국, EU, 일본 등의 선진국에서 활발하게 진행되고 있다. WO$_3$ 박막을 제조하는 방법으로는 sputtering, CVD, 그리고 sol-gel coating 법 등이 있다. sputtering이나 CVD의 경우는 매우 균일하고 전기변색 특성이 좋은 박막을 제조할 수 있는 이점이 있지만 장치의 제조비가 비싸고 대형 패널을 제작하는 데에는 어려움이 있다. 솔-젤 코팅의 경우는 WO$_3$의 전구체인 솔을 합성하고 bath에 솔을 넣은 후 코팅하고자 하는 글라스 기판을 담갔다가 꺼내어 건조하고 열처리하는 간단한 방법으로 제조할 수 있는 장점이 있다. 솔-젤 코팅의 경우 제조비가 값싸고 대면적 코팅이 용이하다는 점이 다른 코팅 방법에 비하여 장점이라고 한 수 있다.다.다.