• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2002년도 High Temperature Superconductivity Vol.XII
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• pp.28-28
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• 2002

• 대한화학회지
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• 제47권6호
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• pp.659-662
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• 2003

• 대한화학회지
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• 제37권9호
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• pp.800-805
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• 1993

정도관리용 생체기준물질 중의 극미량원소에 대한 분석법을 확립하였다. 생체시료를 질산-과산화수소 혼합산화제와 함께 테플론 가압분해용기에 넣어 마이크로파 오븐에서 분해하는 시료전처리법(microwave digestion)을 사용하였다. 시료를 분해시키기 전에 정량할 극미량금속의 안정 동위원소를 첨가하여 동위원소희석 질량분석법을 적용하였다. 혈액과 소나무잎 기준물질에 이러한 분석방법을 적용하여 기준값과 일치되는 결과를 얻었다.

• 한국표면공학회지
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• 제42권5호
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• pp.216-219
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• 2009

A surface acoustic wave (SAW) filter structure was fabricated employing $4{\mu}m$ thick nanocrystalline diamond (NCD) and $2.2{\mu}m$ thick ZnO films on Si wafer. The NCD film was deposited in an $Ar/CH_4$ gas mixture by microwave plasma chemical vapor deposition method. The ZnO film was formed over the NCD film in an RF magnetron sputter using ZnO target and $Ar/O_2$ gas. On the top of the two layers, copper film was deposited by the RF sputter and inter digital transducer (IDT) electrode pattern (line/space : $1.5/1.5{\mu}m$) was defined by the photolithography including a lift-off etching process. The fabricated SAW filter exhibited the center frequency of 1.66 GHz and the phase velocity of 9,960 m/s, which demonstrated that a giga Hertz SAW filter can be realized by utilizing the nanocrystalline diamond thin film.

• 열처리공학회지
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• 제21권5호
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• pp.235-243
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• 2008

Ni-C composite films were prepared using a combination of microwave plasma CVD and ion beam sputtering deposition working in a codeposition way. The structure of these films was characterized by energy-dispersive X-ray diffraction (EDXRD), transmission electron microscopy (TEM) and Raman spectroscopy. It was found that a nickel carbide phase, $Ni_3C$ (hcp), formed as very fine crystallites over a wide temperature range when Ni-C films were deposited at low $CH_4$ flow rates. The thermal stability of this nonequilibrium carbide $Ni_3C$ was also studied. As a result, the $Ni_3C$ carbide was found to decompose into nickel and graphite at around $400^{\circ}C$. With high $CH_4$ flow rates (> 0.2 sccm), the structure of the Ni-C films became amorphous. The formation behavior of the carbide and amorphous Ni-C phases are discussed in relation to the electrical resistivity of the films.

• 분석과학
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• 제15권4호
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• pp.335-340
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• 2002

유도결합 플라스마 질량분석법 (ICP-MS)을 이용하여 모발 중 다원소 동시 정량법을 확립하였다. 0.05 g의 모발 시료에 내부표준물질인 In을 가하고 질산 1.5 mL와 함께 테플론 가압분해 용기에 넣어 마이크로파를 이용하여 분해하는 시료전처리법을 사용하였다. 측정값의 정확도 및 신뢰도를 확인하기 위하여 모발 인증표준물질인 GBW 09101을 반복 분석하였는데 측정값은 인증값과 불확도 범위 내에서 잘 일치하는 결과를 얻었다.

• 한국진공학회지
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• 제1권1호
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• pp.37-42
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• 1992

16M/64M DRAM 제조공정에 적용할 수 있는 ECR 방식의 플라즈마 etcher를 개발 하여 Poly-Si 식각공정에 적용하였다. 공정압력, 사용가스 및 초고주파 전력의 공정변수 변 화에 따른 Poly-Si의 식각율 및 선택비 변화를 조사하였다. 초고주파의 전력이 증가할수록 식각율과 Oxide에 대한 선택비가 증가하는 경향을 보였으며 6mT의 공정압력에서 최적치를 보였다. 공정가스 SF6/SF6 + Cl2의 값이 증가할수록 식각율 및 선택비의 감소가 있었으며 이는 최적 공정변수를 찾지 못하였기 때문으로 분석된다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.231-234
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• 2000

Vertically aligned carbon nanotubes were synthesized on Ni-coated Si substrates using microwave plasma-enhanced chemical vapor deposition. The grain size of Ni thin films was varied with the RF power density during the RF magnetron sputtering process. It was found that the diameter, growth rate, and density of carbon nanotubes could be controlled systematically by the grain size of Ni thin films. With decreasing the grain size of Ni thin films, the diameter of the nanotubes decreased, whereas the growth rate and density increased. High-resolution transmission electron microscope images clearly demonstrated synthesized nanotubes to be multiwalled. The number of graphitized wall decreased with decreasing the diameter. Field emission properties will be further presented.

• 한국표면공학회지
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• 제28권3호
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• pp.133-141
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• 1995

The deposition characteristics of diamond films were investigated for three different substrates : Si, Inconel 600 and steel. Diamond films were prepared by microwave plasma CVD method using $CH_4$, $H_2$ and $O_2$ as reaction gases. The deposited films were analyzed with SEM, Raman spectroscopy and ellipsometer. For Si substrate, diamond films were successfully obtained for most of the deposition conditions used in this study. As the $CH_4$ flow rate decreased and the $O_2$ flow rate increased, the quality of the film was improved due to the reduced non-diamond phase in the film. For Inconel 600 substrate, the surface pretreatment with diamond powders was required to deposit a continuous diamond film. The films deposited at temperatures of $600^{\circ}C$ and $700^{\circ}C$ had mainly diamond phase, but they were peeled off locally due to the difference in the thermal expansion coefficient between the substrate and the deposited films. The films deposited at $500^{\circ}C$ and $850^{\circ}C$ had only the graphitic carbon phase. For steel substrate, all of the films deposited had only the graphitie carbon phase. We speculated that the formation of diamond nuclei on the steel substrate was inhibited due to the diffusion of carbon atoms into the steel substrate which has a large amount of carbon solubility.

• 한국표면공학회지
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• 제29권5호
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• pp.549-555
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• 1996

Diamond Like Carbon film is amorphous film which is considered to consist of three coordinate graphite structure and tetrahedron coordinate diamond structure. Its hardness, thermal conductivity and chemical stability are nearly to one of diamond. It is well known to become semi-conductor by doping of inpurity. In this study Diamond Like Carbon film was synthesized by Microwave Plasma CVD in the gas mixture of hydrogen-methan-nitrogen and doped of nitrogen on the single-crystal silicon or silica glass. The temperature of substrate and nitrogen concentration in the gas mixture had an effect on the bonding state, structural properties and conduction mechanism. The surface morphology was observed by Scanning Electron Microscope. The strucure was analyzed by laser Raman spectrometry. The bonding state was evaluated by electron spectroscopy. Diamond Like Carbon film synthesized was amorphous carbon containing the $sp^2$ and $sp^3$ carbon cluster. The number of $sp^2$ bonding increased as nitrogen concentration increased from 0 to 40 vol% in the feed gas at 1233K substrate temperature and at $7.4\times10^3$ Pa. Increase of nitrogen concentration made Diamond Like Carbon to be amorphous and the doze of nitragen could be controlled by nitrogen concentration of feed gas.