• 대한화학회지
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• 제45권4호
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• pp.351-356
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• 2001

철, 코발트, 니켈 합금을 이용한 탄소확산-수소플라즈마 에칭법으로 다이아몬드 자체막의 표면을 매우 평탄하게 할 수 있었다. 이 방법에서의 다이아몬드 자체막을 합금과 몰리브데늄 기판 사이에 위치시켜 금속-다이아몬드-몰리브데늄(MDM) 샌드위치 형태의 샘플 세 트를 이루게 하였다. 이 샘플세트를 마이크로 웨이브 플라즈마 장치에 장착하여 수소 플라즈마를 발생시켜서 기판온도가 섭씨 1,000 이상이 되도록 하였다. 이와 같은 과정들은 탄소확산-수소플라즈마 방법이라고 하였다. 다이아몬드 자체막 표면을 에칭한 후 표면 거칠기, 표면형상, 에칭한 다이아몬드 표면속의 불순물의 침투를 조사하였다. 결론적으로, 탄소 확산-수소 플라즈마 에칭법은 전자 디바이스에 응용할 수 있는 매우 평탄한 다이아몬드 표면을 형성시키는 방법임을 알 수 있다.

• 한국표면공학회지
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• 제53권3호
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• pp.109-115
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• 2020

In this study, polycrystalline diamond was synthesized by chemical vapor deposition (CVD). Diamond films were deposited on a-plane sapphire substrates while changing the concentration of methane for hydrogen (CH₄/H₂), and the concentrations of methane were 0.25, 0.5, 1, 2, 3 and 4 vol%, respectively. Crystallinity and nucleation density according to changes in methane concentration were investigated. At this time, the discharge power, vacuum pressure, and deposition time were kept constant. In order to deposit polycrystalline diamond, the sapphire substrate was etched with sulfuric acid and hydrogen peroxide (ratio 3:7), and the sapphire surface was polished for 30 minutes with 100 nm-sized nanodiamond particles. The deposited diamond thin film was analyzed by a scanning electron microscope (SEM), a Raman spectra, Atomic force microscope (AFM) and an X-ray diffractometer (XRD). By controlling the ratio of methane to hydrogen and performing appropriate pre-treatment conditions, a polycrystalline diamond thin film having excellent crystallinity and nucleation density was obtained.

• 한국재료학회지
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• 제11권12호
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• pp.1014-1019
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• 2001

The diamond thin film was deposited on Si(100) substrate from$CH_3OH/H_2O$mixtured gas using a hot filament chemical vapor deposition(HFCVD) method. The deposition condition for samples has been varried with the$CH_3OH/H_2O$composition. Scanning electron microscopy(SEM) and Raman spectroscopy has been employed for the sample analysis. The diamond sample has been obtained below 20Pa with$CH_3OH/H_2O$mixtured gas. The crystallinity of diamond film improved as the composition $CH_3OH$decreases from 60Vol% to 52Vol%, and the sample structure changed from the cauliflower to the diamond structure. But the sample structure was becomes cauliflower at 50Vol% of in$CH_3OH$ in the $CH_3OH/H_2O$. It was shown that the$CH_3OH$ has threshold composition.

• 공업화학
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• 제8권1호
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• pp.84-91
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• 1997

대기압하에서 수소를 첨가한 연소염장치를 이용하여 몰리브덴 기판 위에 다이아몬드 필름을 증착시켰다. 기판 온도의 증가에 따라 핵생성밀도가 증가하였으며, $1000^{\circ}C$ 이상에서는 흑연화되고 이것이 수소 원자에 의해 에칭되었다. $C_2H_2/O_2$ 유량비를 증가시킬수록 핵생성밀도는 증가하였지만 결정형태가 구형화되며 비정질카본이 많이 증착되었다. $H_2$를 첨가하면, 표면 활성도가 향상되어 다이아몬드 핵생성밀도가 증가되었으며, 비정질카본을 에칭시켜 우수한 결정성의 다이아몬드 필름을 얻을 수 있었다. 증착시간을 증가시키면 다이아몬드 필름의 두께가 증가하였다.

• 한국진공학회지
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• 제7권3호
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• pp.248-254
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• 1998

PECVD(Plasma Enhanced Chemical Vapor Deposition) 방법을 이용하여 비정질 고 상 탄소 박막의 하나인 유사 다이아몬드(Diamond-Like-Carbon; DLC) 박막을 증착하였다. FT-IR Spectroscopy와 Raman Scattering 등을 통해 박막의 구조적 특징을 조사하였는데, 박막은 microcrystalline diamond domain과 graphitelike carbon domain들이 수소화된 $sp^3$사 면체 구조의 비정질 탄소에 의해 그물 구조로 연결되어진 것으로 보인다. 이러한 추정은 I-V 특성 조사의 결과와도 좋은 일치를 보이는데, 특히 I-V조사에서는 전류의 갑작스러운 증가가 관측되어졌으며 이것은 graphitelike carbon domin들간의 전자 tunneling 현상으로 이해되어진다. 그리고 대단히 얇은 탄소 박막에 대한 Raman산란 조사에서는 증착 초기 상 태에 $\beta$-SiC층이 형성되어지는 것을 확인할 수 있었다.

• Transactions on Electrical and Electronic Materials
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• 제1권1호
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• pp.1-5
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• 2000

Diamond films have been achieved on Si(100) substrates using helicon plasma chemical vapor deposition(HPCVD), Gas mixtures with methane and hydrogen have been used. The growth characteristics were investigated by means of X-ray photoelectroton spectroscopy, Atomic force microscopy and X-ray diffraction. We obtained a plasma density as high as 10$\^$10/~10$\^$11/ cm$\^$-3/ by helicon source. The smooth(100) faces of submicron diamond crystallites were found to exhibit pyramidal shaped architecture, The XPS spectrum for the nucleation layer indicates the presence of diamond at 285.4 eV, close to the reported value of 285.5 eV for diamond , XRD results demonstrates the existence of polycrystalline diamond as the diamond (111) and (220) peaks.

• 한국표면공학회지
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• 제32권3호
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• pp.303-306
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• 1999

On the effect of substrate bias at first stage of diamond synthesis at lower substrate temperature(approximately 673K) using microwave plasma CVD and effect of reaction gas system for the bias enhanced nucleation were studied. The reaction gas was mixture of methane and hydrogen or carbon monoxide and hydrogen. The nucleation density of applied bias -150V using $CH_4-H_2$ reaction gas system, significantly higher than that of $C-H_2$ reaction gas system. When the $CH_4-H_2$ reaction was used, nucleation density was increased because of existence of SiC as a interface for diamond nucleation. By use of this negative bias effect for fabrication of CVD diamond film using two-step diamond growth without pre-treatment, fabrication of the diamond film consist of diamond grains $0.2\mu\textrm{m}$ in diameter was demonstrated

• 한국전기전자재료학회논문지
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• 제14권7호
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• pp.584-589
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• 2001

Diamond thin films were synthesized on WC-Co substrate by RF PACVD(radio frequency plasma-assisted chemical vapor deposition) technique with H$_2$-CH$_4$-O$_2$ gas mixture. WC-Co substrate was pre-treated in HNO$_3$solution, scratched with 3$\mu\textrm{m}$ diamond paste and exposed in the O$_2$ plasma before deposition. The diamond thin film prepared at 11% oxygen concentration showed the best quality of good adhesion and wear resistance at various oxygen concentration with the fixed 5% CH$_4$ concentration.

• 한국세라믹학회지
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• 제26권3호
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• pp.331-340
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• 1989

In this study, it was tried to deposit diamond films from a mixture of CH4 and H2 by the microwave plasma chemical vapor deposition(MWCVD). The MWCVD process was designed and set up from the 2.45GHz microwave generator. And the diamond film was successfully deposited on silicon wafers from the mixture of methane and hydrogen. The microstructures of the deposited diamond films were studied by using the following deposition variables : (a) methane concentration(0.6-10%), (b) reaction pressure(10-100torr), and (c) the substrate temperature(450-76$0^{\circ}C$).

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권7호
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• pp.387-394
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• 2004

Diamond films were deposited on the cemented tungsten carbide WC-Co cutting insert substrates by using both microwave plasma chemical vapor deposition(MWPCVD) and radio frequency plasma chemical vapor deposition (RFPCVD) from $CH_4$$-H_2$$-O_2$ gas mixture. Scanning electron microscopy and X-ray diffraction techniques were used to investigate the microstructure and phase analysis of the materials and Raman spectrometry was used to characterize the quality of the diamond coating. Diamond films deposited using MWPCVD from $CH_4$$-H_2$$-O_2$ gas mixture show a dense, uniform, well faceted and polycrystalline morphology. The compressive stress in the diamond film was estimated to be (1.0∼3.6)$\pm$0.9 GPa. Diamond films which were deposited on the WC-Co cutting insert substrates by RFPCVD from $CH_4$$-H_2$$-O_2$ gas mixture show relatively good adhesion, very uniform, dense and polycrystalline morphology.