• Journal of Ocean Engineering and Technology
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• v.29 no.1
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• pp.94-99
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• 2015

Lead zirconate titanate (PZT) thick films with thicknesses of ㎛ were fabricated on silicon substrates using an aerosol deposition method. A PZT powder solution was prepared using a sol-gel process. The average diameters (d50) obtained were 1.67, 1.98, and 2.40μm when the pyrolysis temperatures were 300℃, 350℃, and 450℃ respectively. The as-deposited film had a uniform microstructure without any cracks or pores. The as-deposited films on silicon were annealed at a temperature of 700℃. The 20-㎛-thick PZT film showed good adherence between the PZT film and substrate, with no tearing observed in the conventional solid phase process. This was probably because the presence of pores produced from organic residue during annealing relieved the residual stresses in the deposited film.

• Journal of the Korean Ceramic Society
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• v.29 no.1
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• pp.29-34
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• 1992

Phase transition, dielectric properties, and leakage current characteristics of Ta2O5 thin film fabricated by sol-gel process with tantalum penta-n-butoxide were studied as a function of annealing temperature in O2 atmoshpere. Although Ta2O5 thin film annealed at temperatures below 700$^{\circ}C$ for 1 hr was amorphous, it was crystallized to ${\beta}$-Ta2O5 of orthorhombic phase by annealing at temperatures higher than 750$^{\circ}C$. With increasing annealing temperature from 500$^{\circ}C$ to 900$^{\circ}C$, dielectric constant of sol-gel processed Ta2O5 thin film was changed from 17.6 to 15.3 due to the increase of SiO2 thickness at Ta2O5/Si interface. For Ta2O5 thin film annealed at 500$^{\circ}C$ to 800$^{\circ}C$ for 1 hr in O2 atmosphere, leakage current was remarkably reduced and breakdown strength was increased with higher annealing temperature. For Ta2O5 film annealed at 800$^{\circ}C$, breakdown did not occur even at electric field strength of 30${\times}$105V/cm and leakage current was maintained lower than 10-8A/$\textrm{cm}^2$.

• 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 $1.16{\times}10^{-4}\;GPU$.

• Journal of the Korean Electrochemical Society
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• v.3 no.1
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• pp.11-14
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• 2000

Transparent conducting ITO thin films have been studied and developed for the solar cell substrate or LCD substrate. ITO thin film has been mostly fabricated by high cost sputtering method. In this research, sol-gel method is applied to fabricate ITO thin film at lower cost. The research is focused on the establishment of process condition and development of precursor. Organic sol was made of indium tri-isopropoxide dissolved in ethylene glycol monoethyl ether. The hydrolysis was controled by addition of acetyl acetone. Tin(IV) chloride was added as dopant. Inorganic sol was made of indium acetate dissolve din normal propanol. Spin coating technique was applied to coat ITO on borosilicate glass. The resistivity of ITO thin film was approximately $0.01\Omega{\cdot}cm$ and the transmittance is higher than $90\%$ in a visible range.

• Journal of Sensor Science and Technology
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• v.20 no.4
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• pp.266-271
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• 2011

A reflection-type fiber-optic pH sensor, which is composed of a pH sol-gel film, plastic optical fibers, a mirror, a light source and a spectrometer, is developed in this study. As pH indicators, a bromthymol blue, a cresol red and a thymol blue are used, and they are immobilized in the sol-gel films. The emitted light from a light source is guided by a fiber-optic Y-coupler and plastic optical fibers to the pH sol-gel film in a pH sensing probe. The pH change in the sensing probe gives rise to a change in the color of the pH sol-gel film, and the optical characteristic of reflected light through the pH sol-gel film is also changed. Therefore, we have measured the spectra of reflected lights, which are changed according to the color variations of the pH sol-gel films with different pH values, by using of a spectrometer. Also, the relationships between the pH values and the intensities of reflected lights are obtained on the basis of the color variations of the pH sol-gel films.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.52.1-52.1
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• 2007

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.484-485
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• 2003

We report on the optimization of the fabrication process of hybrid sol-gel thin film deposition to produce low cost $1 {\times} 16$ splitters for optical communications. We learn that sol-gel film thickness is dependent upon the spinning speeds and viscosity of the sol-gel solutions and refractive index upon the dopant concentrations of Al and Zr in the sol solutions. We could find the optimized physical conditions to achieve the desired thickness of core and cladding layers. We will further carry out the fabrication and measurements of insertion loss, polarization dependent loss (PDL), etc. for the performance of fabricated splitter devices.

• Journal of the Korean institute of surface engineering
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• v.30 no.3
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• pp.183-190
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• 1997

Fabrication and crystallization characteristics of yttria($T_2O_3$) stabilized zirconia(YSZ) thin film by sol-gel process were studied. YSZ sol was synthesized with zirconium n-propoxide($Zr(OC_3H_7)_4)$) and yttrium nitrate pentahydrate ($Y(NO_3)_3.5H_2O$). YSZ film was prepared by depositing the polymeric sol on porous $Al_2O_3$ substrate by spin-coating, and the film characteristics were investigated by FRIR, TG-DTA, XRD, DSC, optical microscopy and SEM. The film topology was uniform and cracks were not found. It was found that the annealing temperature and the concentration of stabilizer affect the crystallization of YSZ film. The YSZ film began to crystallize from amorphous to tetragonal phase at 40$0^{\circ}C$, and it was not converted to cubic structure until $1100^{\circ}C$. It seemed that the grains were formed over $700^{\circ}C$and the average grain size was obtained about 0.2$\mu\textrm{m}$.

• Journal of the Korean Electrochemical Society
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• v.12 no.3
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• pp.251-257
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• 2009

In this study, we fabricated nickel oxide thin film for lithium based electrolyte using sol-gel method. This film was deposited by dip-coating method with mixed solvent of DameH (N,N-dimethylaminoethanol) and DI water. As changing the ratio between DmaeH and DI water, nickel oxide thin film was presented in different charge density and optical transmittance because they were shown various thickness. It was accounted for changing viscosity and density by the ratio of DmaeH and DI water. The thin film synthesized with 1 : 1 ratio of DmaeH and DI water was expressed best electrochromic performance in lithium based electrolyte, because of thick thickness but porous structures.

• Electrical & Electronic Materials
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• v.9 no.7
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• pp.668-673
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• 1996

In this paper, (P $b_{1-x}$ L $a_{x}$)(Z $r_{0.52}$ $Ti_{0.48}$) $O_{3}$ (X=0-13[at%]) thin film were prepared by the Sol-Gel method, Multiple PLZT thin films were spin-coated on the Pt/Ti/ $SiO_{2}$Si substrate. The electrical properties of the films were investigated for varying the annealing temperature. In the PLZT(11/52/48) specimens, the dielectric ocnstant of 1236 and the polarization reversal time of 460[nm] were obtained and the breakdown of the film did not occur up to 1*10$^{10}$ cycles at the voltage of 7[V] by the bipolar acceleration. The remanent polarization and coercive field decreased with increasing the content of La in the range of 0-13[at%] and thin film of the PLZT(11/52/48) showed the value of 2.56[.mu.C/c $m^{2}$] and 21.1[kV/cm], respectively.ly.y.