• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.30-33
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• 2002

In this study, feasibility of using hydrogen peroxide as a chemical oxidant for in-situ treatment by EK-Fenton technology were investigated. Kaolinite, kaolinite/sand mixture and illitic soil spiked by phenol and phenanathrene were used and variation of electrochemical characteristics were examined by EK-Fenton test. For kaolinite that having low buffer capacity, hydrogen peroxide was injected effectively from anode reservoir. However illitic soil that having relatively higher buffer capacity had low hydrogen peroxide introducing efficiency. The test results showed that Hydrogen ions generated by current increased during the treatment decreased under pH 3 in the most of kaolinite specimen. Therefore, stabilized hydrogen oxide was injected more effectively in the kaolinite specimen. This study suggests that efficiency of hydrogen peroxide injection by EK-Fenton thechnoloty is dependent of variation of pH in the soil

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.4-4
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• 2010

Single-crystalline IGZO (Indium-Gallium-Zinc oxide) was fabricated on c-sapphire substrate. Single crystal ZnO was used as a buffer layer, and post-annealing was treated in $900^{\circ}C$ for crystallization of IGZO. Crystallized IGZO formed superlattice structure spontaneously induced to c-axis direction by ZnO butTer layer, the composition of IGZO was varied by amount of ZnO. Crystallinity and composition of IGZO was analyzed by X-ray Diffraction and Transmission Electron Microscopy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.4
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• pp.343-346
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• 2010

We have investigated growth of CdTe thin films by using (As, GaAs) buffer layers for application of large scale IR focal plane arrays(IFPAs). Buffer layers were grown by molecular beam epitaxy(MBE), which reduced the lattice mismatch of CdTe/Si and prevented native oxide on Si substrates. CdTe thin films were grown by metal organic chemical deposition system(MOCVD). As a result, polycrystalline CdTe films were grown on Si(100) and arsenic coated-Si(100) substrate. In other case, single crystalline CdTe(400) thin film was grown on GaAs coated-Si(100) substrate. Moreover, we observed hillock structure and mirror like surface on the (400) orientated epitaxial CdTe thin film.

• Corrosion Science and Technology
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• v.3 no.2
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• pp.54-58
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• 2004

Effects of texture on the electrochemical behaviors of single grains in polycrystalline zinc were investigated using a capillary-based micro-droplet cell. Pontiodynamic sweeps and capacity measurements were carried out in pH 9 borate buffer solution. The cyclic voltammograms and the capacity measurements on single grains with different crystallographic orientations in polycrystalline Zn showed a strong dependence of oxide growth on crystallographic grain orientation. The total charge consumed for oxide formation and the inverse capacity increased with an increase of surface packing density of grain. suggesting the oxide formation was greater on grains with higher surface packing density.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.542-547
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• 2012

We have investigated the electronic properties of the oxide film and anodic oxidation mechanism. Iron was oxidized by two reaction pathways depending on pH. The oxide film has showed the electronic properties of n-type semiconductor based on the Mott-Schottky equation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.306-308
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• 2003

Enantioselective hydrolysis for the production of chiral styrene oxide was investigated using the epoxide hydrolase activity of a newly isolated Rhodosporidium kratochvilovae SYU-08. The effects of reaction parameters - buffer type, pH, temperature, initial substrate concentrations, phenyl-1,2-ethanediol concentrations on hydrolysis rate, and enantioselectivity - were analyzed. Optically active (S)-styrene oxide with an enantiomeric excess higher than 99 % was obtained from its racemate. with a yield of 38 % (theoretically 50% maximum yield) from an initial concentration of 80 mM.

• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.609-614
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• 2014

We fabricated amorphous zinc tin oxide (ZTO) transparent thin-film transistors (TTFTs). The effects of Al electrode on the mobility and threshold voltage of the ZTO TTFTs were investigated. It was found that the aluminum (Al)-ZTO contact decreased the mobility and increased the threshold voltage. Traps, originating from $AlO_x$, were assumed to be the cause of degradation. An indium tin oxide film was inserted between Al and ZTO as a buffer layer, forming an ohmic contact, which was revealed to improve the performance of ZTO TTFTs.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.73-78
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• 2009

Zinc Oxide (ZnO) nanorods arrays were deposited on ZnO buffered p-Si(100) substrates by hydrothermal method. The ZnO buffer layer with a thickness of 30 nm was deposited by metal oxide chemical vapor deposition at $500^{\circ}C$. The structural and optical properties of ZnO nanorods arrays controlled by precursor concentrations from 0.06 to 0.5 M were studied by FE-SEM(field emission scanning electron microscopy), XRD(X-ray diffraction), and PL(photoluminescence), respectively. It was found that the structural and optical properties of ZnO nanorods arrays are changed significantly with increase of precursor concentration. The sizes of diameter and length of nanorods were increased as the concentration increase, and good optical property was shown with the concentration of 0.3 M.

• Transactions on Electrical and Electronic Materials
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• v.8 no.6
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• pp.260-264
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• 2007

We have studied stability in organic light-emitting diode depending on buffer layer and cathode. A transparent electrode of indium-tin-oxide(ITO) was used as an anode. An electron injection energy barrier into organic material is different depending on a work function of cathodes. Theoretically, the energy barriers for the electron injection are 1.2 eV, -0.1 eV, and 0.0 eV for Al, LiAl, and LiF/Al at 300 K, respectively. We considered the cases that holes are injected to organic light-emitting diode. The hole injection energy barrier is about 0.7 eV between ITO and TPD without buffer layer. For hole-injection buffer layers of CuPc and PEDOT:PSS, the hole injection energy barriers are 0.4 eV and 0.5 eV, respectively. When the buffer layer of CuPc and PEDOT:PSS is existed, we observed the effects of hole injection energy barrier, and a reduction of operating-voltage. However, in case of PVK buffer layer, the hole injection energy barrier becomes high(1.0 eV). Even though the operating voltage becomes high, the efficiency is improved. A device structure for optimal lifetime condition is ITO/PEDOT:PSS/TPD/$Alq_3$/LiAl at an initial luminance of $300cd/m^2$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.316-316
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• 2008

Using an evaporation method, $SiO_2$ was deposited as a buffer layer between a flexible PET substrate and a ITO film deposited by DC magnetron sputtering and electro-optical properties were investigated with thickness variance of $SiO_2$ layers. After coating a $SiO_2$ layer and a ITO film, the ITO/$SiO_2$/PET was heated up to $200^{\circ}C$ and the resistivity and the transmittance were measured by hall effect measurement system and UV/VIS/NIR spectroscopy. As a result of depositing a $SiO_2$ buffer layer, the resistivity increased and the transmittance and adhesion property were enhanced than ITO films with no buffer layers and the resistivity was lowered as $SiO_2$ thickness increased from 50 $\AA$ to 100 $\AA$. It was found that the transmittance was independent of annealing temperature variance in $150^{\circ}C{\sim}200^{\circ}C$ and the resistivity decreased as the temperature increased and especially decreasing rate of the resistivity was higher as the buffer layer thickness was thinner. So under optimized depositing of $SiO_2$ buffer layers and post-annealing of ITO/$SiO_2$/PET, ITO films with enhanced adhesion, electro-optical properties can obtained.