• The Korean Journal of Ceramics
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• 제2권4호
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• pp.212-215
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• 1996

This paper focuses the strength and wear resistance of CVD diamond films. The strength of free-standing CVD diamond films synthesized by microwave plasm CVD, DC plasma CVD, RF plasma CVD and arc discharge plasma jet CVD has been measured by three-point bending test. The wear resistance of CVD diamod films has been evaluated by the pin-on-disk type testing. diamond films coated on the base of sintered tungsten carbide pin by hot filament CVD have been rubbed with a sintered diamond disk in muddy water. Volume removed wear of CVD diamond has been compared with stellite, WC alloy and bearing steel.

• 한국세라믹학회지
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• 제28권10호
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• pp.777-784
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• 1991

Diamond films have been growth by the hot-filament chemical vapor deposition (HFCVD) using CH4 and H2 gaseous mixture on the Si substrate. The experimental results indicated that the deposits were pure diamond and contained no amount of non-diamond phases such as amorphous carbon or graphite. The diamond films were deposited well at the conditions: the filament temperature of 210$0^{\circ}C$, the substrate temperature of 77$0^{\circ}C$, the CH4 concentration of 1.76%, the reactor pressure of 30 torr, and the deposition time of 7 hr. At this growth condition, the maximum deposition rate was 2 ${\mu}{\textrm}{m}$/hr. X-ray diffraction patterns and texture coefficient results showed that preferred orientation of the diamond films was {111} orientation under all experimental conditions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1533-1536
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• 2001

To grow the diamond films by using RF-MW two step process, at first, diamond seeds were deposited on silicon substrate by RF plasma CVD, and then a diamond layer grown by MW plasma CVD on the seeds. The grain-size of diamond films deposited by using RF-MW two step process was smaller and denser and also, crystallity of diamond film was better than those of the MW plasma CVD process. The deposited diamond films were analyzed by SEM(scanning electron microscophy), XRD (x-ray diffraction), and Raman spectroscopy.

• 한국전기전자재료학회논문지
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• 제15권8호
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• pp.726-730
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• 2002

Electro-optical (EO) performances of the ion beam (IB) aligned twisted-nematic (TN)-liquid crystal display (LCD) with ion beam exposure on the new diamond-like carbon (DLC) thin film surface were investigated. A good voltage-transmittance (V-T) curve of the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min was observed. Also, the fast response time of the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min can be achieved. Finally, the residual DC voltage of the ion beam aligned TN-LCD on the DLC thin film surface is almost the same as that of the rubbing aligned TN-LCD on a polyimide (Pl) surface.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.346-349
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• 2001

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of diamond like carbon (DLC) thin film. A high pretilt angle of about $4^{\circ}$ was measured by ion beam(IB) exposure on the DLC thin film surface. A good LC alignment was observed by the IB alignment method on the DLC thin film surface at annealing temperature of $200^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $220^{\circ}C$. Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment can be achieved by the IB alignment method on the DLC thin film surface.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.346-349
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• 2001

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of diamond like carbon (DLC) thin film. A high pretilt angle of about 4$^{\circ}$ was measured by ion beam(IB) exposure on the DLC thin film surface. A good LC alignment was observed by the IB alignment method on the DLC thin film surface at annealing temperature of 200$^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of 220$^{\circ}C$ . Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment can be achieved by the IB alignment method on the DLC thin film surface.

• 조명전기설비학회논문지
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• 제25권4호
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• pp.79-87
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• 2011

In this paper, the best conditions for the deposition of the high quality diamond thin-film from N-hexane as a carbon source in the microwave plasma process was carried out. Major parameters are the deposition time, flow rates of oxygen and hexane. The deposition time for the steady state thin-film was required more than 4[h], and the suitable flow rates of hexane and oxygen for the high-quality thin-film are 0.4[sccm] and 0.1~0.2[sccm], respectively. In addition, amorphous carbons such as DLC and graphite were grown by increasing the flow rate of hexane, and it decreased by increasing the flow rate of oxygen. Specifically, the growth rate is about 1.5[${\mu}mh-1$] under no addition of oxygen and it decreased about 60[%] as ca. 1.0[${\mu}mh-1$] with oxygen.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.135.2-135
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• 1998

• 한국결정성장학회지
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• 제15권1호
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• pp.10-15
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• 2005

Microwave plasma CVD 다이아몬드/Ti 박막 성장 시 CH₄/H₂ 가스의 유량비율, chuck bias, microwave power 등이 다이아몬드 박막의 구조적 특성과 입자밀도에 미치는 영향에 대하여 조사하였다. 2∼3 CH₄ Vol.% 조건일 때 sp³-결합성의 탄소 neutral 들이 우선적으로 형성되고 sp²-결합성의 탄소 neutral 들이 선택적으로 제거됨에 따라 양질의 다이아몬드 박막을 얻을 수 있었으며, 다이아몬드 입자 증착 기구를 해석하였다. Ti 기판에 걸어준 negative chuck bias가 증가함에 따라 다이아몬드 핵생성이 증진되어 다이아몬드 입자 밀도가 증가하였고, 임계 전압은 약 -50V 임을 확인하였다. 또한, microwave power가 증가함에 따라 미세결정질(micro-crystalline) graphite 층 생성이 제어되고 다이아몬드 층이 형성됨을 확인하였다.

• The Korean Journal of Ceramics
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• 제3권1호
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• pp.5-12
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• 1997

Charged carbon clusters which are formed by the gas activation are suggested to be responsible for the formation of the metastable diamond film. The number of carbon atoms in the cluster that can reverse the stability between diamond and graphite by the capillary effect increases sensitively with increasing the surface energy ratio of graphite to diamond. The gas activation process produces charges such as electrons and ions, which are energetically the strong heterogeneous nucleation sites for the supersaturated carbon vapor, leading to the formation of the charged clusters. Once the carbon clusters are charged, the surface energy of diamond can be reduced by the electrical double layer while that of graphite cannot because diamond is dielectric and graphite is conducting. The unusual phenomena observed in the chemical vapor deposition diamond process can be successfully approached by the charged cluster model. These phenomena include the diamond deposition with the simultaneous graphite etching, which is known as the thermodynamic paradox and the preferential formation of diamond on the convex edge, which is against the well-established concept of the heterogeneous nucleation.