• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.73-73
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• 1996

• Proceedings of the Korean Vacuum Society Conference
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• 1997.02a
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• pp.173-173
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• 1997

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.261-261
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• 2009

탄소나노튜브(CNT)는 우수한 기계적, 화학적, 전기적 특성 때문에 전자방출원, 가스저장매체, 약물전달시스템 그리고 전기화학적 소자 등의 응용으로 주목받고 있다 [1-3]. 이러한 응용을 위하여 플라즈마 이온조사법을 이용하여 열화학증기증착법(TCVD)으로 성장된 수직배향 탄소나노튜브(VCNT)의 구조변화를 도모하고, 그 메커니즘을 연구하였다.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.3
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• pp.18-27
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• 1998

Molecular dynamicsinvestigations of ion implantation considering point defect generation were performed with ion energies in the range of ~1keV, Simulation starts perfect diamond cubic lattice site. Stillinger-Weber potential and ZBL potential were used to calculate forces between atoms. We have simulated slowing-down of ion velocity, ion trajectory and coupled-coing between ion and silicon. We also discussed distribution of point defect using rdial distribution function. We found that interstitial produced by ion bombardment mainly formed interstitial cluster.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.206-211
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• 1987

The photoreaction of 5,7-dimethoxycoumarin with adenosine has been carried out in a dry film state. The mixture of DMC and adenosine was irradiated with 350 nm UV light and two major products were isolated. The structure was determined by various spectroscopic measurements involving $^{13}C$ nuclear magnetic resonance and fast atom bombardment mass spectrometry. These addition products were produced by covalent bond formation between the pyrone ring at carbon 3 or 4 and the sugar ring moiety of adenosine at carbon 5'.

• Journal of Satellite, Information and Communications
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• v.9 no.3
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• pp.22-26
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• 2014

This paper introduces homogeneous liquid crystal (LC) orientations on chemically modulated polystyrene (PS) surfaces using various ion beam (IB) exposure time. Transparent PS was replaced with conventional polyimde material. Especially, PS has higher transparent property than conventional polyimide thin film and it means PS is more suitable material for producing high brightness mobile LCD. As a non-contact process, IB bombardment process induced LC orientation in the direction parallel to the IB process. Through x-ray photoelectron spectroscopy, it was shown that the chemical compositional changes of the IB-irradiated PS surfaces were determined as a function of IB exposure time. Using this analysis, the optimal IB bombardment condition was determined at IB exposure time of up to 15 s. Moreover, thermal stability on IB-irradiated PS surfaces were carried out which showed that a relatively high IB exposure time induced a thermally stable LC alignment property. And it has a highly potential of mobile high transparent mobile LCD such as smart phone display and mobile information device.

• Analytical Science and Technology
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• v.6 no.4
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• pp.349-357
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• 1993

Analytical methods of thromboxane $B_2(TXB_2)$ using various techniques of Fast Atom Bombardment mass spectrometry (FAB MS) were studied, static FAB condition was investigated to obtain linear response curve using docosanoic acid as a internal standard. For maximum sensitivity, a continuos-flow(CF-) FAB MS by selected-ion monitoring(SIM) with devised sample introduction system, has been developed to quantiate thromboxane $B_2$ in biological sample. Instrumental parameters affecting sensitivity, reproducibility has been studied. The method has been optimized with respect to the eluent, 0.75% glycerol(in EtOH v/v) and flow rate of $3.7{\mu}l/min.$ Under the condition, detection limits were below 10pg in SIM mode and a good linear relationship between dose and response was achieved.

• 전자공학회논문지 IE
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• v.44 no.2
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• pp.26-31
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• 2007

A surface treatment was performed after the screen printing of a carbon nanotube paste for obtaining the carbon nanotube field emission array(CNT FEA) on the soda-lime glass substrate. In this experiment, Ar ion bombardment was applied as an effective surface treatment method. After making a cathode electrode on the glass substrate, photo sensitive CNT paste was screen-printed, and then back-side was exposure by uv light. Then, the exposed CNT paste was selectively remained by development. After post-baking, the remained CNT paste was bombarded by accelerated Ar ions for removing some binders and exposing only CNTs. As results, the field emission characteristics were strongly depended on the accelerating energy. At 100 eV, the emission was highest and as the acceleration energy increases more then 100 eV, the emission decreased. This was due to the removal of CNT itself as well as binders.

• Transactions on Electrical and Electronic Materials
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• v.12 no.2
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• pp.60-63
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• 2011

We investigated the etching characteristics of zinc oxide (ZnO) and the effect of additive gases in a $Cl_2$-based inductively coupled plasma. The inert gases were argon, nitrogen, and helium. The maximum etch rates were 44.3, 39.9, and 37.9 nm/min for $Cl_2$(75%)/Ar(25%), $Cl_2$(50%)/$N_2$(50%), and $Cl_2$(75%)/He(25%) gas mixtures, 600 W radiofrequency power, 150 W bias power, and 2 Pa process pressure. We obtained the maximum etch rate by a combination of chemical reaction and physical bombardment. A volatile compound of Zn-Cl. achieved the chemical reaction on the surface of the ZnO thin films. The physical etching was performed by inert gas ion bombardment that broke the Zn-O bonds. The highly oriented (002) peak was determined on samples, and the (013) peak of $Zn_2SiO_4$ was observed in the ZnO thin film sample based on x-ray diffraction spectroscopy patterns. In addition, the sample of $Cl_2$/He chemistry showed a high full-width at half-maximum value. The root-mean-square roughness of ZnO thin films decreased to 1.33 nm from 5.88 nm at $Cl_2$(50%)/$N_2$(50%) plasma chemistry.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.291-299
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• 2004

DLC films were deposited using the ECR-PECVD method with the fixed deposition condition, such as ECR power, methane and hydrogen gas-flow rates and deposition time, for various substrate bias voltage. We have investigated the ion bombardment effect induced by the substrate bias voltage on films during the deposition of film. The characteristic of the films were analyzed using the FTIR, Raman, and UV/Vis spectroscopy analysis shows that the amount of dehydrogenation in films was increased with the increase of substrate bias voltage and films thickness was decreased. Raman scattering analysis shows that integrated intensity ratio(ID/IG) of the D and G peak was increased as the substrate bias voltage increased and films hardness was increased. Optical transmittances of DLC film were decreased with increasing deposition time and substrate bias voltage. From these results, it can be concluded that films deposited at this experimental have the enhanced characteristics of DLC because of the ion bombardment effect on films during the deposition of film.