• Journal of the Korean institute of surface engineering
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• v.29 no.5
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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.

• Journal of the Korean Vacuum Society
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• v.12 no.1
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• pp.25-34
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• 2003

Deposition behavior of hard amorphous carbon film was investigated by molecular dynamic simulation using Tersoff potential which was suggested for the interaction potential between carbon atoms. When high energy carbon atoms were collided on diamond (100) surface, dense amorphous carbon film could be obtained. Physical properties of the simulated carbon film were compared with those of the film deposited by filtered cathodic arc process. As in the experimental result, the most diamond-like film was obtained at an optimum kinetic energy of the incident carbon atoms. The optimum kinetic energy was 50 eV, which is comparable to the experimental observation. The simulated film was amorphous with short range order of diamond lattice. At the optimum kinetic energy condition, we found that significant amount of carbon atom were placed at a metastable site of distance 2.1 $\AA$. By melting and quenching simulation of diamond lattice, it was shown that this metastatic peak is Proportional to the quenching rate. These results show that the hard and dense diamond-like film could be obtained when the localized thermal spike due to the collision of high energy carbon atom can be effectively dissipated to the lattice.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.243-245
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• 1994

We synthesized the conducting diamond-like carbon films using plasma-enhanced chemical vapor deposition and analysized its characteristics. We obtained the metal-containing diamond-like carbon films using $CH_4$, Ar gas and aluminum target. We observed the changes of electrical conductivity, microhardness and surface morphology according to $Ar/CH_4$ ratio, substrate bias and target bias. As the target bias and $Ar/CH_4$ ratio increase and the substrate bias decreases, the electrical conductivity and surface roughness increase. The increase of hardness involves decrease of the electrical conductivity. Metal-containing amorphous hydrogenated carbon films show improved adhesion on metal substrates compared to pure diamond-like carbon films and better electrical conductivity.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.5
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• pp.77-83
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• 2022

A high-hardness tool material is required to reduce extreme abrasive wear when drilling carbon fiber reinforced plastic (CFRP). Single-crystal diamond is the hardest material in the world, but it is very expensive to be used as a cutting tool. Polycrystalline diamond (PCD) is a diamond grit fused at a high temperature and pressure, and diamond-like carbon (DLC) is an amorphous carbon with high hardness. This study compares DLC coatings and PCD inserts to conventional TiAlN-coated tungsten carbide drills. In fiberglass and carbon fiber reinforced polymer drilling, the tool wear of DLC-coated carbide was approximately half that of TiAlN-coated tools, and slight tool wear occurred in the case of PCD insert end drills.

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.248-254
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• 1998

DLC(Diamond-Like-Carbon) thin film, one of the solid state amorphous carbon films, has been deposited by the method of PECVD (Plasma Enhanced Chemical Vapor Deposition). The structural features have been characterized using both FT-IR Spectroscopy and Raman Scattering. The film is considered to consist of microcrystalline diamond domains and graphitelike carbon domains, which are interconnected by hydrogenated $sp^3$ tetrahedral carbons. This shows a good agreement with the results by I-Vmeasurements. In I-Vstudy, the sudden increase of current has been observed and this phenomenon is understood to be due to the tunneling effect between graphitelike domains. A characteristic feature related to the $\beta$-SiC has been identified in the study of Raman Scattering for the very thin film, which suggests that a buffer layer forms at the interface of the Si substrate and the carbon film.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.101-101
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• 2016

DLC(Diamond Like Carbon)막은 그 물성의 다양함으로 인하여 산업기계, 금형, 공구, 광학 및 수송기기의 파워셀 부품등 많은 산업분야에 활용되고 있다. 일반적으로 DLC막은 증착에 사용되는 카본의 원료에 따라 크게 두 가지로 나눌 수 있는데, 이는 탄화 수소계 가스(CxHy)를 사용하여 증착된 a-C:H(amorphous Hydro-Carbon)과 고체 카본을 사용하는 a-C(amorphous Carbon)이다. 또한 a-C 중 진공 아크 공법으로 제작된 막(ta-C : tetrahedral amorphous-Carbon)은 다이아몬드 성분인 sp3의 분률이 높아, 그 경도는 40 - 85 GPa 이상이며, 무수소화로 500도 이상의 고온에서도 그 물성의 변화가 적어 그 활용도가 높아지고 있다. 하지만 높은 경도와 더불어 막의 잔류응력이 높아 3 um 이상 후막화하는 것은 어렵다. 이는 높은 잔류응력으로 인한 막의 증착시, 막 자체가 파손되거나, 기판과 막사이의 계면 밀착력이 약하여 박리되거나, 또는 높은 밀착력으로 인하여 모재가 파손되는 등 다양한 문제를 발생한다. 본 연구에서는 이 고경도 무수소 DLC막(ta-C)의 후막화하는 방안으로 주요 코팅 변수와 잔류응력과의 관계를 에너지 관점에서 파악하고 이를 활용 잔류응력을 제어하여 할 수 있는 방법을 제시하고자 한다.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.434-434
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• 2011

Electrochemical method have been employed in this work to modify the chemical vapour deposited nitrogen doped hydrogen amorphous diamond-like carbon (N-DLC) film to fabricate nickel and copper nano particle modified N-DLC electrodes. The electrochemical behaviour of the metal nano particle modified N-DLC electrodes have been characterized at the presence of glucose in electrolyte. Meanwhile, the N-DLC film structure and the morphology of metal nano particles on the N-DLC surface have been investigated using micro-Raman spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy. The nickel nano particle modified N-DLC electrode exhibits a high catalytic activity and low background current, while the advantage of copper modified N-DLC electrode is drawn back by copper oxidizations at anodic potentials. The results show that metal nano particle modification of N-DLC surface could be a promising method for controlling the electrochemical properties of N-DLC electrodes.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.1
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• pp.49-53
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• 2011

Diamond-like carbon (DLC) films is a metastable form of amorphous carbon containing a significant fraction of Sp3 bond. DLC films have been characterized by a range of attractive mechanical, chemical, tribological, as well as optical and electrical properties. In this study DLC films were prepared by the RF magnetron sputter system on $SiO_2$ substrates using graphite target. The effects of the post annealing temperature on the Property variation of the DLC films were examined. The DLC films were annealed at temperatures ranging from 300 to $500^{\circ}C$ using rapid thermal process equipment in vacuum. The variation of electrical property and surface morphology as a function of annealing treatment was investigated by using a Hall Effect measurement and atomic force microscopy. Raman and X-ray photoelectron spectroscopy analyses revealed a structural change in the DLC films.

• Journal of the Korean Chemical Society
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• v.34 no.5
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• pp.396-403
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• 1990

We describe how to design and construct a LPCVD (Low Pressure Chemical Vapor Deposition) apparatus which can be applicable to the study of reaction mechanism in general CVD experiments. With this apparatus we have attempted to make diamond like carbon films on the p-type (111) Si wafer from (H$_2$ ＋ CH$_4$) gas mixtures. Two different methods have been tried to get products. (1)The experiment was carried out in the reactor with two different inlet gas tubes. One coated with phosphoric acid was used for supplying microwave discharged hydrogen gas stream, and methane has been passed through the other tube without the microwave discharge. In this method we got only amorphous carbon cluster products. (2) The gas mixture (H$_2$ ＋ CH$_4$) has been passed through the discharge tube with the Si wafer located in and/or near the microwave plasma. In this case diamond-like carbon products could be obtained.

• Tribology and Lubricants
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• v.20 no.3
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• pp.125-131
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• 2004

Nano-wear behavior of amorphous carbon films was studied by Atomic Force Microscopy. The a-C films are deposited on Si(100) substrate by DC magnetron sputtering method. The influences of different surface roughness on the nano-wear are investigated. Nano-wear tests were carried out using a very sharp diamond coated tip. Its spring constant was 1.6 N/m and radius of curvature was 110 nm. Normal force used in the wear tests ranged 0 to 400 nN. It was found that surface depression occurred during scratching because of plastic deformation and abrasive wear (cutting St ploughing). Wear depth increased linearly with normal force. Changing the surface roughness variables according to the bias pulse control, the less surface roughness decreased the wear depth. The thickness did not affect the wear resistance.