• Journal of the Korean Vacuum Society
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• v.8 no.1
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• pp.26-30
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• 1999

Sputter deposited Co-Cr thin films been developed continuously as one of the major candidates for high density recording media. In this study, Co-26at%Cr thin films with c-axis oriented normal to substrate surface were prepared by a improved facing targets sputtering system. We find that the effect of microstructural changes of the sputtered Co-Cr thin films on magnetic properties and changes of crystal orientation due to the variation of substrate temperature.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.2
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• pp.162-166
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• 2007

The ITO thin films were prepared by facing targets sputtering (FTS) system on polycarbonate (PC) substrate. The ITO thin films were deposited with a film thickness of 100 nm at room temperature. As a function of sputtering conditions, electrical and optical properties of prepared ITO thin films were measure. The electrical and optical characteristics of the ITO thin films were evaluted by Hall Effect Measurement (EGK) and UV/VIS spectrometer (HP), respectively. From the results, the ITO thin films was deposited with a resistivity $8{\times}10^{4}\;{\Omega}-cm$ and transmittance over 80 %.

• Journal of the Semiconductor & Display Technology
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• v.11 no.1
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• pp.61-65
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• 2012

In this study, for use of carbon nanotubes (CNTs) as a cold cathode of x-ray tubes, we examine the effects of selective growth of CNTs on their field emission properties and long-term stability. The selective growth of CNTs was performed by selectively etching the catalyst layer which was used for CNTs' nucleation. CNTs were grown on conical-type tungsten substrates using an inductively-coupled plasma chemical vapor deposition system. For all the grown CNTs, their morphologies and microstructures were analyzed by field-emission scanning electron microscope and Raman spectroscopy. The electron-emission properties of CNTs and the long-term stability of emission currents were measured and characterized according to the CNTs' growth position on the substrate.

• Journal of the Semiconductor & Display Technology
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• v.11 no.1
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• pp.7-11
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• 2012

One dimensional and two dimensional nano patterns were fabricated on a 4-inch substrate by Laser Interference Lithography (LIL). Mach-Zehnder interferometer was setup to obtain the interference patterns and adjusted the pattern sizes with change of incident angle. We could obtain a periodic structure with a period of 440 nm using 266 nm laser, and demonstrated a pattern size with $293{\pm}25nm$ over a 4-inch substrate.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.25-29
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• 2014

This research was aimed to fabricate an optical fiber-based SERS substrate which can detect dopamine neurotransmitters. Chitosan nanoparticles (NPs) were firstly anchored on the surface of optical fiber, and then gold layer was subsequently deposited on the anchored chitosan NPs via electroless plating method. Finally, chitosan-gold nanocomposites combined with optical fiber reacted with dopamine molecules of 100-1500 mg/day which is a standard daily dose for Parkinson's disease patients. The amplified Raman signal at $1348cm^{-1}$ obtained from optical fiber-based SERS substrate was plotted versus dopamine concentrations (1-10 mM), demonstrating an approximate linearity of Y = 303.03X + 2385.8 ($R^2$ = 0.97) with narrow margin errors. The optical fiber-based Raman system can be potentially applicable to in-vitro (or in-vivo) detection of probe molecules.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.6
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• pp.491-495
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• 2014

We developed a compact high-precision slot-die coating machine for thin-film deposition on a flexible substrate. For smooth and precise coating, air-bearing and linear motor system were employed to minimize velocity ripple. The gap control mechanism is specially designed to have repeatability of gap between nozzle and substrate under 1 ${\mu}m$. Due to extremely precise gap control, the machine can coat thin-films down to 50 nm with $200mm{\times}100mm$ size. A thin film of Ag nano-particle ink is coated for demonstration.

• Journal of the Semiconductor & Display Technology
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• v.19 no.1
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• pp.17-22
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• 2020

Recently, the decrease in thin film thickness has been actively studied by changing several physical elements such as the increase in revolution velocity of lower substrate equipped with AC or DC motor. In this paper, we propose a novel spin coater control system that changes AC or DC motor and common use software with limitation of velocity and position control into step motor and LABVIEW software based on GUI to control revolution velocity and position more precisely. By determining six input values of rotation velocity 1, 5, 10, 25, 50, 100 PPS, we fabricated six samples using coating target, TA(tantalum) on silicon substrate and measured their thin film thickness by SEM. Hence, this research can be applied to inferring thin film thickness of tantalum regarding any value of revolution velocity without additional experiments and for linear reference model via property analysis of thin film thickness using other thin-film materials.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.4
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• pp.59-66
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• 2008

Anaerobic digestion system is getting more attractive in that it produces biogas in the process of organic waste stabilization. Net energy production is important when biogas production is concerned. In this study, net energy production was evaluated with respect to biogas production and heat losses in a hypothetical digester. Under the condition of digester operation with slurry inflow of 5% of TS, additional fuel is required to maintain digester temperature during the winder season. Substrate therefore, needs to have higher VS contents through co-digestion of silage or food waste that has greater values of methane production rate. Heating input slurry is important in cold season, which covers over 80% of heating requirement. Heat recovery from digestate is valuable to reduce the use of biogas for heating. It seems desirable to minimize slurry inflow when temperature is very low. Psychrophilic digestion may be a feasible option for reducing heating requirement.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.9
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• pp.772-775
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• 2009

Indium tin oxide(ITO) thin film was deposited at room temperature on polycarbonate(PC) substrate by in-line sputter system. ITO sputtering process was carried out at a various pressure for the reduction of ion damage on PC substrate and the electrical and the optical properties of deposited ITO films were obtained and analyzed. From the experimental results, the sheet resistances of as-deposited ITO films varied with a different pressure and the optical transmittances at visible wavelength were maintained above 85%. The results are considered to be related to the pressure of oxygen atoms as a reaction gas.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.403-404
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• 2008

In this study, we prepared ITO thin film on glass, polycarbonate (PC) and polyethersulfone (PES) substrate in Facing Targets sputtering (FTS) system. Properties of as-deposited thin films's aging change were investigated as a function of time placed in the air. The electrical and optical properties of as-deposited thin films were employed by a four point probe and an UV/VIS spectrometer, an X-ray diffractometer (XRD), a Field Emission Scanning Electron Microscope(FESEM) and a Hall Effect measurement. As a result, as time went by, transmittance of all films did not change but resistivity of films was decreasing.