• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.5
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• pp.240-246
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• 2002

$TiO_2$ films on soda-lime-silica glasses were prepared by spin coating-pyrolysis process using titanium naphthenate as a starting material. As-deposited films were pyrolyzed at $500^{\circ}C$ for 10 min in air and annealed at 500, 550 and $600^{\circ}C$ for 30 min in air. Crystallinity of the film was investigated by X-ray diffraction analysis. A field emission-scanning electron microscope and an atomic force microscope were used for characterizing the surface morphology and the surface roughness of the film. After annealing at 550 and $600^{\circ}C$, the X-ray diffraction patterns consist of only anatase peak. Films annealed at 500 and $550^{\circ}C$ exhibited flat surfaces. While with the increase in annealing temperature to $600^{\circ}C$, the $TiO_2$ film showed abnormal growth of three-dimensional needle-shaped grains. For all samples, high transmittance, above 90 % at 500 nm, was obtained at visible range. To investigate photocatalytic properties, IR absorbance associated with the C-H stretching vibrations of a thin solution-cast film of stearic acid under 365 nm (2.4 mW/$\textrm{cm}^2$) UV irradiation was estimated.

• Journal of the Korean Ceramic Society
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• v.39 no.9
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• pp.884-889
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• 2002

In order to investigate the calcium phosphate forming ability of nanocrystalline $ZrO_2$ film, we prepared $ZrO_2/Si$ structure by using a chemical solution deposition with a zirconium naphthenate as a starting material. Precursor sol was spin-coated onto the (100)Si substrate and prefired at 500$^{\circ}C$ for 10 min in air, followed by final annealing at 800$^{\circ}C$ for 30 min in air. Crystallinity of the annealed film was examined by X-ray diffraction analysis. Surface morphology and surface roughness of the film were characterized by field emission-scanning electron microscope and atomic force microscope. After annealing, nanocrystalline $ZrO_2$ grains were obtained on the surface of the film with a homogeneous interface between the film and substrate. After immersion for 1 or 5 days in a simulated body fluid, formation of calcium phosphate was observed on $ZrO_2$ film annealed at 800$^{\circ}C$ by energy dispersive X-ray spectrometer. The fourier transform infrared spectroscopy revealed that carbonate was substituted into the calcium phosphate.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.1
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• pp.17-22
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• 2007

Metal-doped $TiO_2$ thin films were prepared on soda-lime-silica glass substrates by using a spin coating-pyrolysis process. As-deposited films were prefired at $500^{\circ}C$ or 10 min in air. Five-coated films were finally annealed at $600^{\circ}C$ for 30 min in air. High resolution X-ray diffraction, field emission scanning electron microscope and UV spectrophotometer were used to analyze film's property. The largest red shift in optical energy gap is obtained in the Fe-doped $TiO_2$ film.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.2
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• pp.56-62
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• 2003

Epitaxial $Bi_4Ti_3O_{12}$ films on $SrTiO_3$(100), L$aA1O_3$(100) and MgO(100) were prepared by sol-gel process using metal naphthenate as a starting material. As-deposited films were pyrolyzed at $500^{\circ}C$ for 10 min In air and annealed at $750^{\circ}C$ for 30 min in air. Crystallinity and in-plane alignment of the film were investigated by X-ray diffraction $\theta$-2$\theta$ scan and P scanning. A field emission-scanning electron microscope and an atomic force microscope were used for characterizing the surface morphology and the surface roughness of the film. The film prepared on MgO(100) showed the most poor crystallinity and in-plane alignment, compared to those on the other substrates. While the films on $LaA1O_3$(100) and $SrTiO_3$(100) having high crystallinity and in-plane alignment showed the form of columnar grain growth, the film on MgO(100) which had poor crystallinity showed the form of acicula grain growth.