• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.703-706
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• 2006

Zinc oxide nanocrystals are attractive candidates for a solution-processable semiconductor for high performance thin film field effect transistors. We have studied ZnO thin film transistor fabricated by solution process and have improved $V_{th}$ by controlling the ZnO ink additives. Synthesized ZnO nanoparticles of 30nm were dispersed in solvent to make the ZnO ink. ZnO ink was spin coated on silicon wafer and after heat treatment electrodes were patterned.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.314-324
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• 1996

Scanning probe microscopes (SPMs) such as the scanning tunneling microscope (STM) and the atomic force microscope (AFM) were used for surface modification tools at the nanometer scale. Material surfaces, i. e., titanium, hydrogen-terminated silicon and trimethylsilyl organosilane monolayer on silicon, were locally oxidized with the best lateral spatial resolution of 20nm. The principle behind this proximal probe oxidation method is scanning probe anodization, that is, the SPM tip-sample junction connected through a water column acting as a minute electrochemical cell. An SPM-nanolithogrphy process was demonstrated using the organosilane monolayer as a resist. Area-selective chemical modifications, i. e., etching, electroless plating with gold, monolayer deposition and immobilization of latex nanoparticles; were achieved in nano-scale resolution. The area-selectivity was based on the differences in chemical properties between the SPM-modified and unmodified regions.

• Journal of Integrative Natural Science
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• v.2 no.4
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• pp.289-292
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• 2009

Perchlorosilanes are useful precursors for the synthesis of hydrosilanes for the fabrication of electronic devices such as silicon thin-film transistors and silicon nanoparticles. For this solution process, requirements of precursors applicable to solution process are relatively low volatile and soluble in common organic solvents. In this work, the decaphenylcyclopentasilane has been obtained from the reaction of the lithium wire and dichlorodiphenylsilane. The reaction of decaphenylcyclopentasilane with lewis acid catalyst, HCl/$AlCl_3$, gives the perchlorocyclopentasilane. Decaphenylcyclopentasilane exhibits an unusual optical property. Its optical property was characterized by UV-vis and fluorescence spectroscopy. Absorption wavelength maxima for the decaphenylcyclopentasilane was 272 nm. Decaphenylcyclopentasilane displayed an emission band at 741 nm with excitation wavelength of 272 nm.

• Journal of Powder Materials
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• v.28 no.5
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• pp.423-428
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• 2021

Here, we report the development of a new and low-cost core-shell structure for lithium-ion battery anodes using silicon waste sludge and the Ti-ion complex. X-ray diffraction (XRD) confirmed the raw waste silicon sludge powder to be pure silicon without other metal impurities and the particle size distribution is measured to be from 200 nm to 3 ㎛ by dynamic light scattering (DLS). As a result of pulverization by a planetary mill, the size of the single crystal according to the Scherrer formula is calculated to be 12.1 nm, but the average particle size of the agglomerate is measured to be 123.6 nm. A Si/TiO₂ core-shell structure is formed using simple Ti complex ions, and the ratio of TiO₂ peaks increased with an increase in the amount of Ti ions. Transmission electron microscopy (TEM) observations revealed that TiO₂ coating on Si nanoparticles results in a Si-TiO₂ core-shell structure. This result is expected to improve the stability and cycle of lithium-ion batteries as anodes.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.115-127
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• 1999

The charged clusters or particles, which contain hundreds to thousands of atoms or even more, are suggested to form in the gas phase in the thin film processes such as CVD, thermal evaporation, laser ablation, and flame deposition. All of these processes are also used in the gas phase synthesis of the nanoparticles. Ion-induced or photo-induced nucleation is the main mechanism for the formation of these nanoclusters or nanoparticles inthe gas phase. Charged clusters can make a dense film because of its self-organizing characteristics while neutral ones make a porous skeletal structure because of its Brownian coagulation. The charged cluster model can successfully explain the unusual phenomenon of simultaneous deposition and etching taking place in diamond and silicon CVD processes. It also provides a new interpretation on the selective deposition on a conducting material in the CVDd process. The epitaxial sticking of the charged clusters on the growing surface is gettign difficult as the cluster size increases, resulting in the nanostructure such as cauliflowr or granular structures.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.419-419
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• 2014

Interdigitated nanogap device (IND) is an attractive tool for biomolecular detection due to its huge on-off signal ratio, great tolerance to the variation in biochemical environment, and relatively simple implementation processes. Here, we report on the IND-based detection of Influneza A virus by sandwich immunoassay. The INEs were fabricated by photo lithography followed by the in-house chemical lithographic technique for the narrowing the initial gap distance. The surface of the silicon oxide between the two gold electrodes was chemically modified to immobilize primary antibodies for the immuno-specific interaction with the influenza A virus antigen. After immersing the functionalized-IND into the sample solution containing the influenza A virus, the device was exposed to the secondary antibody conjugated Au nanoparticles (Au NPs). The INDs showed a huge jump in the electric conductance when the sample solution contained the influenza A virus of the concentration as low as 10 ng/mL. We hope that this IND-based sensing can be applied to the development of simple and reliable diagnostic means of influenza viruses.

• Textile Coloration and Finishing
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• v.29 no.3
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• pp.131-138
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• 2017

Most of high performance fabrics for the car racing protective clothing have been developed to have thermal resistance, flame retardant property, impact resistance and anti-frictional properties to protect the racer from the crucial accident. In this study, the meta-aramid fabric, which has inherent flame retardant, was coated with nanoparticles of SiC to enhance the impact resistance and anti-friction properties. Uniform coating of the nanoparticles onto the fabrics was obtained by using tape casting method. As the experimental parameters, size and content of the SiC nanoparticle were varied with the coating conditions of the fabric surface. The effects of the nanoparticle coating on the properties of meta-aramid fabric were examined with various instrumental analyses such as SEM, tensile strength and abrasion test.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.9
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• pp.593-597
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• 2015

Ni ink for electrohydrodynamic (EHD) continuous jet printing has been developed by using Ni nanoparticles mixed with conhesiveness provider. EHD continuous jet printing was used in order to realize $20{\mu}m$ pattern width. Ink stability was investigated by using Turbi-scan which monitors agglomeration and precipitation of nanoparticles in the ink for three days. The Turbi-scan results showed that the formulated Ni ink had been stable for 3 days without any indication of precipitation across the entire ink. Antireflection coating (ARC) layer in crystalline solar cell wafers was removed by laser ablation technique leading to the formation of 84 grooves where the Ni ink was printed by EHD continuous jet printing. The printability and microstructure of EHD-jet-printed Ni lines were investigated by using optical and electron microscopes. 84 Ni lines with the width less than $20{\mu}m$ were successfully printed by one-time printing without any misalignment and fill the laser-ablated ARC grooves.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.268.2-268.2
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• 2013

Nanogap interdigitated electrodes (NIDEs) can serve as an alternative platform for the biomolecular detection [1]. In this work, the NIDEs were adopted in a simple and sensitive detection of Pneumococcal surface protein A (PspA). The NIDEs were fabricated by the combination of photo and chemical lithography. Photolithographically-defined initial gap of about 200 nm was narrowed down to a few tens of nanometers by surface-initiated growth of the initial electrodes (chemical lithography) [2]. Bare silicon oxide surface between the electrodes was chemically modified to immobilize capturing antibodies and, after exposure to the samples, the device was immersed in a solution containing the probe-antibody-conjugated Au nanoparticles (Au NPs). The conductance change accompanied with the Au NP immobilization was interpreted as the existence of PspA. Detection limit of the measurements and further improvement of the detection efficiency were discussed with the results from I-V analysis, scanning electron microscopy, and atomic force microscopy.

• Journal of Powder Materials
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• v.28 no.3
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• pp.233-238
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• 2021

Iron-based amorphous powder attracts increasing attention because of its excellent soft magnetic properties and low iron loss at high frequencies. The development of an insulating layer on the surface of the amorphous soft magnetic powder is important for minimizing the eddy current loss and enhancing the energy efficiency of high-frequency devices by further increasing the electrical resistivity of the cores. In this study, a hybrid insulating coating layer is investigated to compensate for the limitations of monolithic organic or inorganic coating layers. Fe₂O₃ nanoparticles are added to the flexible silicon-based epoxy layer to prevent magnetic dilution; in addition TiO₂ nanoparticles are added to enhance the mechanical durability of the coating layer. In the hybrid coating layer with optimal composition, the decrease in magnetic permeability and saturation magnetization is suppressed.