• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.295-295
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• 2010

Nanoparticles of the compound semiconductor, Cu(In, Ga)Se2 (CIGS), were synthesized in solution under ambient pressure below $100^{\circ}C$ and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), optical absorption spectroscopy and energy-dispersive X-ray (EDX) analyses. These materials have chalcopyrite crystal structures and the particle sizes less than 100 nm. Synthetic conditions were studied for the crystallized CIGS nanoparticles formation to prevent from side products of Cu2Se, Cu2-xSe, and CuSe etc. The single phase CIGS nanoparticles were applied to coating of thin films photovoltaic cells. The electro deposition of CIGS thin films is also a good non-vacuum technology and under investigation. In aqueous solutions, the different chemical compositions of CIGS thin films were obtained, depending on pH, concentration of starting materials and deposition potentials. The surface morphology of the prepared CIGS thin films depends on the complexing ligands to the solutions during the electrochemical deposition.

• Journal of Integrative Natural Science
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• v.3 no.2
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• pp.112-116
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• 2010

Prepared CdSe nanoparticles were systems, one of the most studied and useful nanostructures. Semiconductor quantum dots (QDs) have been the subject of much interest for both fundamental reseach and technical applications in recent years, due mainly to their strong size dependent properties and excellent chemical processibility. CdSe nanocrystals were synthesized by using sol-gel process. Synthesized CdSe quantum dots were studied to evaluate the optical, electronic and structural properties using UV-absorption, and photoluminescence (PL) measurement. Prepared CdSe nanoparticles were subjected to sense hydrofluoric acid. Photoluminescence was quenched upon adding of hydrofluoric acid.

• Journal of Adhesion and Interface
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• v.24 no.1
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• pp.1-8
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• 2023

A conjugated polymer is the next-generation emerging semiconductor material that can be applied in various fields, from organic electronics to biomedical applications. However, its low solubility in an aqueous medium has made the use of toxic organic solvents inevitable, thereby leading to formulation of conjugated polymers in the form of waterborne nanoparticles. This review paper discusses two principles of nanoparticle formation and representative methods for synthesizing conjugated polymer nanoparticles.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.3
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• pp.15-25
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• 2023

In this study, silicon sludge from semiconductor dicing process is recycled to fabricate silica nanoparticles, which are applied as dispersing materials for electro-responsive (ER) smart fluid. In specific, metal impurities are removed from silicon sludge by acid washing to obtain the high-purity silicon powder. And then, silica nanoparticles are synthesized by facile hydrothermal method employing the silicon powder as reactant material. To control the size of silica nanoparticles, the reaction time of hydrothermal method is varied as 8, 15, 20, and 30 hours are applied to control the size of silica nanoparticles. Sizes of silica nanoparticles are increased proportionally to the reaction time owing to the increased numbers of hydrolysis and condensation reactions. As-synthesized silica nanoparticles are prepared as electro-responsive smart fluids by dispersing into silicon oil. Silica nanoparticles synthesized by 30 hours of hydrothermal reaction (SiO₂-H30) exhibit the highest shear stress of 21.4 Pa under an applied electric field strength of 3.0kV mm^-1. Such enhancement in ER performance of SiO₂-H30 among various silica nanoparticles are attribute to the reinforcing effect originated from the mixed particle size, which allowing the formation of rigid chain-like structures. Accordingly, this study successfully propose a recycling method of silicon sludge to synthesize silica nanoparticles and their derived ER fluids, which may suggest new possibility to ESG management emphasizing the eco-friendliness.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2833-2834
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• 2013

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.2
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• pp.101-105
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• 2006

Nanoscale floating-gate characteristic of colloidal Au nanoparticles electrostatically assembled on the oxidized surface of Si nanowires have been investigated. The Si nanowire split-gate transistor structure was fabricated by electron beam lithography and subsequent reactive ion etching. Colloidal Au nanoparticles with ${\sim}5$ nm diameters were selectively deposited onto the Si nanowire surface by 2 min electrophoresis. It was found that electric fields applied to the self-aligned split side gates allowed charge to be transferred on the Au nanoparticles. It was observed that the depletion mode cutoff voltage, induced by the self-aligned side gates, was shifted by more than 1 V after Au nanoparticle electrophoresis. This may be due to the semi-one dimensional nature of the narrow Si nanowire transport channel, having much enhanced sensitivity to charges on the surface.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.396-396
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• 2009

Chalcopyrite semiconductor $CuInSe_2$ nanoparticles were prepared using a low temperature colloidal route by reacting the starting materials (CuI, $InI_3$ and $Na_2Se$) in solvents. After synthesised $CuInSe_2$ nanoparticles precursors were mixed with organic binder for the viscosity of the precursor slurry to be suitable for the doctor blade method. The mixture of $CuInSe_2$ and binder was deposited onto molybdenum-coated sodalime glass substrates to form thin film. The precursor thin films were preheated on the hot plate to remove remaining solvents and binder material. After subsequent thermal processing of the thin film under a selenium ambient, $CuInSe_2$ absorber layer with grain size significantly lager than that of the nanoparticles was formed.

• Advances in environmental research
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• v.5 no.1
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• pp.61-77
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• 2016

$NanoTiO_2$ was synthesized by ultrasonication assisted sol-gel process and subjected to iron doping and carbon-iron codoping. The synthesized catalysts were characterized by XRD, HR-SEM, EDX, UV-Vis absorption spectroscopy and BET specific surface area analysis. The average crystallite size of pure $TiO_2$ was in the range of 30 - 33 nm, and that of Fe-$TiO_2$ and C-Fe $TiO_2$ was in the range of 7 - 13 nm respectively. The specific surface area of the iron doped and carbon-iron codoped nanoparticles was around $105m^2/g$ and $91m^2/g$ respectively. The coupled semiconductor photo-Fenton's activity of the synthesized catalysts was evaluated by the degradation of a cationic dye (C.I. Basic blue 9) and an anionic dye (C.I. Acid orange 52) with concurrent investigation on the operating variables such as pH, catalyst dosage, oxidant concentration and initial pollutant concentration. The most efficient C-Fe codoped catalyst was found to effectively destruct synthetic dyes and potentially treat real textile effluent achieving 93.4% of COD removal under minimal solar intensity (35-40 kiloLUX). This reveals the practical applicability of the process for the treatment of real wastewater in both high and low insolation regimes.

• Journal of the Semiconductor & Display Technology
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• v.17 no.3
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• pp.36-40
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• 2018

We have developed a nonlithographic patterning technique using polystyrene nanoparticles to form nanonet channel structures which is promising for high-performance TFT applications. Nanoparticles assisted patterning (NAP) is a technique to form uniform nano-patterns by applying lift-off and dry etch process. Oxygen plasma treatment was used to control the diameters of nanonet hole size to realize a branch width down to 100 nm. NAP technology can be very promising to fabricate nanonet structure with advantages of lower manufacturing cost and large-area patterning capability.

• Transactions on Semiconductor Engineering
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• v.1 no.1
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• pp.9-13
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• 2023

An AlGaN/GaN heterojunction-based hydrogen sensor with SnO₂ nanoparticles/Pd catalyst layer was fabricated for room-temperature hydrogen detection. The fabricated sensor exhibited unstable drift in standby current when it was operated at room temperature. The instability in the sensing signal was dramatically improved when the sensor was operated under UV illumination.