• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.123-126
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• 2010

$Cu_2O$ nanoparticles-based films are fabricated by spin-coating on glass substrates and their optoelectronic characteristics are investigated in this study. The $Cu_2O$ films are nearly all-transparent as high as 98% in a wavelength range from 400 nm to 900 nm and three exciton peaks associated with the sublevels in the conduction band are observed at the wavelengths shorter than 400 nm in the absorption spectrum. Under the illumination of the 325 nm wavelength light, the photocurrent efficiency of the $Cu_2O$ film is $1.8\times10^5 {\mu}A/W$ at a voltage of 2.5 V in air.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.389-398
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• 2000

Photocatalytic removal of benzene from air was examined using titanium dioxide photocatalyst films prepared on soda lime glass(50$\times$50$\times$2 mm) by spin coating and chemical vapor deposition. For the measurement of photocatalytic reactivity titanium dioxide coated glass was placed into a batch reactor and concentration of benzene in the reactor was set to abuot 100 ppm, and then illuminated with UV. It was found that catalytic reactivity of titanium dioxide films increased with the increase of titanium dioxide film thickness and then level off beyond a certain film thickness. UV absorption by the films showed the similar trend. The formation of stoichiometric amount of carbon dioxide was confirmed by measurement of carbon dioxide concentration in the reactor. In general spin coated films revealed better photocatalytic reactivity than chemically deposited one within the experimental ranges covered in this study. Morphology and crystal structure of prepared films were investigated by XRD and SEM and they showed significant difference between spin coated films and CVD films. Highest quantum efficiency of prepared titanium dioxide photocatalyst was close to 50%.

• Journal of the Korean institute of surface engineering
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• v.34 no.3
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• pp.258-263
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• 2001

Siloxane thin films were fabricated on a silicon wafer by spin-coating using a siloxane solution made by the sol-gel process. Fluorine was doped using$ CF_4$ plasma treatment. The film was then annealed in-situ state in the nitrogen atmosphere. In order to examine the influence of annealing and fluorine doping on the siloxane thin film, thermogravimetric-differential thermal analysis (TG-DTA), Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) were used and the dielectric constant was determined by the high-frequency capacitance-voltage method. Stable siloxane films could be obtained by in-situ annealing in a nitrogen atmosphere after $CF_4$ plasma treatment, and the dielectric value of the film was $\varepsilon$ 2.5.

• Journal of the Korean institute of surface engineering
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• v.40 no.2
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• pp.98-102
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• 2007

[ $NiCl_2$ ] and poly-L-lysine coated protein chip plates have been fabricated using a spin coating system. Water has been used as solvent and scratching effects on glass slides and ITO have been investigated. We also observed the surface properties of $NiCl_2$ and poly-L-lysine coated slides by using PSA(Particle size analyzer) and AFM(Atomic force microscope). The AFM results imply that the surface patterns created in the spin coating system determine the protein adsorption. Adsorption of histidine-tagged KRS proteins immobilized on glass slides and ITO was analyzed using a BAS image system. The results suggest that the scratching effect was increased ability of protein adsorption.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.1
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• pp.7-10
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• 2002

$TiO_2$ thin films were prepared by coating and subsequent pyrolysis processes using Titanium-naphthenate as a raw material. $TiO_2$ thin films were made by spin-coating technique on the glass substrates, and heat treated at 45$0^{\circ}C$, The transmittance, refractive index, crystallinity and surface morphology of the $TiO_2$ thin films were measured by UV/Vis spec trophotometer, x-ray diffractometer and scanning electron microscope. $TiO_2$thin films on the slide glass showed the trans mittance of 70-90% and refractive index of 2.6 at 420 nm. The results of XRD and SEM showed that the $TiO_2$ thin films exhibited the anatase phase and the thread-like surface morphology.

• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.31-31
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• 2009

• Food Science and Biotechnology
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• v.16 no.4
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• pp.646-649
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• 2007

The effect of the addition of 2 kinds of chemically modified starches (the anti-caking agents; tapioca starch and com starch) on caking of ramen soup was observed using a low-resolution proton-pulsed nuclear magnetic resonance (NMR) technique. After storing ramen soup samples with diverse compositions of modified starch at 20-40% relative humidity for 4 weeks, changes in the spin-spin relaxation time constant ($T_2$) were measured as a function of temperature. $T_2-Temperature$ curves for ramen soup containing modified starches showed that the caking initiation temperature (glass transition temperature) was increased by $5^{\circ}C$ following the addition of only 0.5% modified cornstarch. The results indicate that the modified com starch used in this study would be an effective anti-caking agent for ramen soup, thus prolonging the shelf life of the product.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.6
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• pp.460-464
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• 2020

This study reports the fabrication and application of semitransparent Cu nanoparticle layers. Spin coating and subsequent drying of a Cu colloid solution were performed to deposit Cu nanoparticle layers onto Si and glass substrates. As the spin speed of the spin coating increases, the density of the nanoparticles on the substrate decreases, and the agglomeration of nanoparticles is suppressed. This microstructural variation affects the optical properties of the nanoparticle layers. The transmittance and reflectance of the Cu nanoparticle layers increase with increasing spin speed, which results from the trade-off between the exposed substrate area and surface coverage of the Cu nanoparticles. Since the glass substrates coated with Cu nanoparticle layers are semitransparent and colored, it is anticipated that the application of a Cu nanoparticle-dielectric bilayer structure to transparent solar cells will improve the cell efficiency as well as aesthetic appearance.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.39-43
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• 1998

Single crystals of{{{{ { Zn}_{ 1-x} {Mn }_{x }{Te} }}}} with x=0.3-0.6 were prepared by the standard Bridgeman method. Diffuse neutron diffraction intensities due to the short range magnetic ordering is found in the vicinities of 1 1/2 0 reciprocal point and its equivalent point, indicating that the magnetic correlation of the clusters is the type III antiferromangetic one do the F-type Bravais class crystals, being identical with that of {{{{{ Cd}_{ 1-x} {Mn }_{x }Te }}}}. Neutron inelastic scattering measure-ment has been performed for {{{{{ Zn}_{ 0.6} { Mn}_{ 0.4}Te }}}} sample using the cold neutron spectrometer. AGNES. High resolution measurement with the energy resolution of {{{{ TRIANGLE E= +- .01meV}}}} was carried out in the temperature range from 10K to the ambient. Critical scattering, closely related with the spin glass transition, has been observed for the first time in this semimagnetic semi-conductor. The critical scattering is observed at temperatures in the vicinity of the spin glass transition temperature, 17K. The scattering is observed as a kind of quasielastic scattering in the reciprocal range where the elastic magnetic diffuse scattering has been observed, e.g., 11/20 reciprocal point, indicating the spin fluctuation has dynamic components in this material. Photoconductivity has been discovered below 150K in {{{{{ Zn}_{ 0.4} {Mn }_{0.6 } Te}}}}. The electric AC conductivity has been increased dramatically under the laser light with the wave lengths of {{{{ lambda =6328,5145 and4880 }}}}$\AA$ ,respectively. After the light was darkened, the conductivity was reduced to the original level after about 2000 seconds at 50K, being above the spin glass transition temperature. This phenomenon is the typical persistent photoconductivity; PPC which was similarly found in {{{{ { Zn}_{ 1-x} { Mn}_{x} Te}}}}.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.987-991
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• 2009

We report growth of vertically well-aligned zinc oxide (ZnO) nanorods on indium-tin oxide (ITO)/glass substrates using a simple aqueous solution method at low temperature via control of the ZnO seed layer morphology. ZnO nanoparticles acting as seeds are pre-coated on ITO-coated glass substrates. by spin coating to control distribution and density of the ZnO seed nanoparticles. ZnO nanorods were synthesized on the seed-coated substrates in a dipping process into a main growth solution. It was found that the alignment of ZnO nanorods can be effectively manipulated by the spin-coating speed of the seed layer. A grazing incidence X-ray diffraction pattern shows that the ZnO seed layer prepared using the higher spin-coating speed is of uniform seed distribution and a flat surface, resulting in the vertical growth of ZnO nanorods aligned toward the [0001] direction in the main growth process.