• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.913-914
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• 2006

Amorphous diamond has a very low work function (1 eV) at modest temperature ($150^{\circ}C$). It has been coat coated on electron emitting electrodes. Such electrodes are used for cold cathode fluorescence lamps (CCFL) that illuminate liquid crystal displays (LCD) for rnote books and television sets. Amorphous diamond can dramatically reduce the turn-on voltage to lit CCFL so the lamp life can be greatly extended. Moreover, the electrical current can be increased to enhance the brightness of the light.

• The Korean Journal of Ceramics
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• v.4 no.1
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• pp.1-4
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• 1998

Diamond film was deposited on Mo substrate at atmospheric pressure using combustion flame apparatus with the addition of H2. At a temperature above 100$0^{\circ}C$, parts of the film were converted into graphites and these were etched by hydrogen atoms. With increasing $C_2H_2/O_2$ ratio, the nucleation density of the film increased. But the greater part of the film was formed with cauliflower-shaped amorphous carbon. These amorphous carbn were crystallized etching amorphous carbon.

• Journal of Surface Science and 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.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1148-1148
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• 2006

• 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.

• Journal of Surface Science and Engineering
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• v.33 no.2
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• pp.69-76
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• 2000

The rf plasma chemical vapor deposition is a common method employed for diamond or amorphous carbon deposition. Diamond possesses the strongest bonding, as exemplified by a number of unique properties-extraordinary hardness, high thermal conductivity, and a high melting tempera tore. Therefore, it is very important to investigate the synthesis of semiconducting diamond and its use as semiconductor devices. An inductively coupled rf plasma CVD system for producing amorphous carbon films were developed. Uniform temperature and concentration profiles are requisites for the deposition of high quality large-area films. The system consists of rf matching network, deposition chamber, pumping lines for gas system. Gas mixtures with methane, and hydrogen have been used and Si (100) wafers used as a substrate. Amorphous carbon films were deposited with methane concentration of 1.5% at the process pressure of S torr~20 torr, and process temperature of about $750^{\circ}C$. The nucleation and growth of the amorphous carbon films have been characterized by several methods such as SEM and XRD.

• Journal of Surface Science and Engineering
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• v.50 no.3
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• pp.177-182
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• 2017

The properties of electroless Ni-B thin film on diamond powder with different parameters (temperature, pH, surfactant etc.) were studied. The surface morphology, structure and composition distribution of the Ni-B film were observed by field effect scanning electron microscope (FE-SEM), energy-dispersive spectrometer (EDS), X-ray diffraction (XRD) and Auger electron spectroscopy (AES). The growth rate of Ni-B film was increased with increase of bath temperature. The B content in Ni-B film was reduced with increase of bath pH. As a result the structure of Ni-B film was changed from amorphous to crystalline structure. The PVP in solution plays multi-functional roles as a dispersant and a stabilizer. The Ni-B film deposited with adding 0.1 mM-PVP was strongly introduced an amorphous structure with higher B content (25 at.%). Also the crystallite size of Ni-B film was reduced from 12.7 nm to 5.4 nm.

• Applied Chemistry for Engineering
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• v.8 no.1
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• pp.84-91
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• 1997

Diamond film was deposited on Mo substrate at atmospheric pressure using a combustion flame apparatus with the addition of $H_2$. With the substrate temperature, the nucleation density of the substrate was increased. At temperatures above $1000^{\circ}C$, some of diamond was partly converted into graphite and etched by hydrogen atoms. With an increase of the $C_2H_2/O_2$ ratio, the nucleation density was increased. But crystals were cauliflower-shaped and a large number of amorphous carbon were deposited. With the addition of $H_2$, the nucleation density of diamond was increased by the improvement of surface activity. Diamond film of high crystallinity was deposited by etching amorphous carbon. With an increase of deposition time, the thickness of diamond film was increased.

• Korean Journal of Materials Research
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• v.10 no.8
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• pp.575-580
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• 2000

Diamond thin films were deposited on $Si_3N_4$, SiC, TiC and $Al_2O_3$, substrates by the CVD method using Ta(TaC)Filament, and the appearance of the diamond films and their adhesion properties were examined by SEM, optical microscopy, indentation test and compression topple test. Diamond films were deposited at lower $CH_4$ concentration than 5%$CH_4$ for all kinds of the substrate material, but graphitic(amorphous)carbon was observed at 10%$CH_4$. The diamond film of about $12\mu\textrm{m}$ thickness on WC substrate partly peeled off, but the film on $Si_3N_4$ substrate held good adhesion. The indentation test showed that roughly ground surface was very effective for adhesion of diamond films to substrate. The topple test revealed that film thickness was an important factor governing the adhesion of the diamond film.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.905-908
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• 2000

The growth properties of diamond grain were examined by Raman spectroscopy and microscope images. Diamond thin films were prepared on single crystal Si wafers by microwave Plasma chemical vapor deposition. Preparation conditions, substrate temperature, boron concentration and deposition time were controlled differently. Prepared diamond thin films have different surface morphology and grain size respectively Diamond grain size was gradually changed by substrate temperature. The biggest diamond grain size was observed in the substrate, which has highest temperature. The diamond grain size by boron concentration was slightly changed but morphology of diamond grain became amorphous according to increasing of boron concentration. Time was also needed to be a big diamond grain. However, time was not a main factor for being a big diamond grain. Raman spectra of diamond film, which was deposited at high substrate temperature, showed sharp peaks at 1334$cm^{-1}$ / and these were characteristics of crystalline diamond. A broad peak centered at 1550$cm^{-1}$ /, corresponding to non-diamond component (sp$^2$carbon), could be observed in the substrate, which has low temperature.