• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.11a
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• pp.235-239
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• 2001

In recent years, as Chemical Mechanical Planarization(CMP) has been routinely utilized in integrated circuit(IC) fabrication, the consumption of slurry, main consumable in a CMP process, is greatly increased. Thus the reprocess of CMP slurries has been actively considered in the industry to reduce cost-of-consumable (COC). The main purpose of this study was to recycle the used oxide slurry using filters as a new method. As a result, Ultra Fine(UF) Filter could distinguish silica from the used oxide slurry and Reverse Osmosis(RO) Filter could distinguish Deionized(DI) Water and chemistry from chemistry solution. The tetraethylorthosilicate removal rate was almost the same as the number of recycle polishing was increased, when it was modified by slightly adding new SS-12 slurry. The microscratch didnt found as the number of recycle polishing was increased.

• Electrical & Electronic Materials
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• v.16 no.9
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• pp.61.1-61
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• 2003

Stoichiometric, uniform, amorphous ZrO$_2$ films with an equivalent oxide thickness of ∼1.5nm and a dielectric constant of ∼18 were deposited by an atomic layer controlled deposition process on silicon for potential application in meta-oxide-semiconductor(MOS) devices. The conduction mechanism is identified as Schottky emission at low electric fields and as Poole-Frenkel emission at high electric fields. the MOS devices showed low leakage current, small hysteresis(〈50mV), and low interface state density(∼2*10e11/cm2eV). Microdiffraction and high-resolution transmission electron microscopy showed a localized monoclinic phase of ${\alpha}$-ZrO$_2$ and an amorphous interfacial ZrSi$\_$x/O$\_$y/ layer which has a correspondign dielectric constant of 11

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.4
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• pp.282-287
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• 2006

A Caulobacter crescentus epoxide hydrolase(CCEH) from a recombinant Escherichia coli was purified to homogeneity using a three-step procedure. The CCEH protein was purified 7.3-fold with a 22.9% yield in overalll activity. The optimal reaction temperature and pH were determined to be $37^{\circ}C$ and pH 8.0, respectively. The addition of 10%(v/v) dimethylsulfoxide as a cosolvent improved the enantioselectivity of CCEH for a batch kinetic resolution of racemic indene oxide.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.392-395
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• 2008

In an attempt to delineate the direct effect of arsenite-induced endothelial dysfunction on nitric oxide (NO) production, confluent bovine aortic endothelial cells (BAEC) were incubated with arsenite, and endothelial NO synthase expression and NO production were measured. Exposure of arsenite decreased NO production for up to 24h. This decrease was accompanied by decreases in cAMP, protein kinase A (PKA) activity, and furthermore, significant reduction of pCREB. In conclusion, this study is the first to demonstrate that exposure of arsenite decreases NO production by a reduction of pCREB and PKA activity that may be mediated by cAMP, leading to endothelial dysfunction.

• Environmental Engineering Research
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• v.19 no.1
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• pp.101-105
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• 2014

Three magnesium compounds, $MgO_2$, MgO, and $Mg(OH)_2$, which are supposed to supply oxygen continuously, were applied onto contaminated bay sediment and its ecology in order to activate the local microbial flora. Those compounds were found to reduce chemical oxygen demand (COD), total nitrogen (T-N), and total phosphorus (T-P). Magnesium oxide, in particular, reduced COD by 30% and T-N and T-P considerably. All compounds also suppressed the release of pollutants in the order $MgO_2$, MgO, and $Mg(OH)_2$. Analysis of microbial flora showed that the microbial group treated by $MgO_2$ and $Mg(OH)_2$ was predictably stable; meanwhile, that treated by MgO increased the number of species, but decreased the total number of microorganisms.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.620-623
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• 2001

The peculiarities of using Self-propagating High-temperature Synthesis (SHS) and solid state phase synthesis for production of high temperature superconductor materials are discussed. Oxide superconductors with general formula $ReBa_2$$Cu_3$$O_{7-x}$ (Re= Y, Yb, Sm, Nd) have been made with using barium oxide initial powder instead of traditional barium carbonate. X-ray powder diffraction showed a single phase orthorhombic perovskite structure was produced in all reactions. Phenomena observed during the grinding of the reactant mixture are presented. Mechano-chemical activation - as a pretreatment of the reactant mixture - strongly influences the kinetic parameters, the reaction mechanism, and the composition and structure of the final product.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.378-379
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• 2006

CMP(chemical mechanical polishing) process has been attracted as an essential technology of multi-level interconnection. However, the COO(cost of ownership) is very high, because of high consumable cost. Especially, among the consumables, slurry dominates more than 40 %. So, we focused how to reduce the consumption of raw slurry. In this paper, $ZrO_2$, $CeO_2$, and $MnO_2$ abrasives were added de-ionized water (DIW) and pH control as a function of KOH contents. We have investigate the possibility of new abrasive for the oxide CMP application.

• Resources Recycling
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• v.12 no.6
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• pp.3-7
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• 2003

For the manufacture of iron oxide, the hydro-process and the pyre-process are conventionally used. Both processes use a huge amount of chemicals in reaction which affect the environment harmfully. This paper introduced the new environment friendly processes; the bio-chemical process and the self propagating high temperature synthesis process.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3299-3302
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• 2014

The In2S3 thin films of tetragonal structure and In2O3 films of cubic structure were synthesized by a spin coating method from the organometallic compound precursor triethylammonium indium thioacetate ($[(Et)_3NH]^+[In(SCOCH_3)_4]^-$; TEA-InTAA). In order to determine the electron mobility of the spin-coated TEA-InTAA films, thin film transistors (TFTs) with an inverted structure using a gate dielectric of thermal oxide ($SiO_2$) was fabricated. These devices exhibited n-channel TFT characteristics with a field-effect electron mobility of $10.1cm^2V^{-1}s^{-1}$ at a curing temperature of $500^{\circ}C$, indicating that the semiconducting thin film material is applicable for use in low-cost, solution-processed printable electronics.

• Bulletin of the Korean Chemical Society
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• v.28 no.7
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• pp.1171-1174
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• 2007

We have developed an electrochemical immunosensor that combines the electrocatalytic property of carbon nanotube and the low background current of indium tin oxide (ITO) electrode. A partial monolayer of carboxylated single-walled carbon nanotube (CCNT) is covalently formed on an ITO electrode modified with amine-terminated phosphonic acid. Nonspecifically adsorbed avidin on the hydrophobic sidewalls of CCNT is used to immobilize biotinylated antibody and to reduce the nonspecific binding to CCNT. The biotinylated antimouse IgG bound on avidin and the antimouse IgG conjugated with alkaline phosphatase (ALP) sandwiches a target mouse IgG. ALP catalyzes the conversion of p-aminophenyl phosphate monohydrate into p-aminophenol, which is electrocatalytically oxidized to p-quinone imine on CCNT surface. Moderate electrocatalytic electrode obtained with the combination of CCNT and ITO allows low detection limit (0.1 ng/ mL).