• 한국재료학회:학술대회논문집
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• 한국재료학회 2002년도 춘계 학술발표강연 및 논문개요집
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• pp.132-132
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• 2002

Diamond is well known as the hardest material in nature. It also has other unique bulk physical and mechanical properties, such as very high thermal conductivity and broad optical transparency, which enable a number of new applications now that large areas of diamond can be fabricated by the new diamond plasma chemical vapor deposition (CVD) technologies. A study on the effects of growth kinetics and properties of diamond films obtained by addition of argon (~7 vol. %) into the methane/hydrogen mixture is carried out using HFCVD system. A negative bias was used as a nucleation enhancement method in addition to the argon dilution. The scanning electron microscopy (SEM) image of surface morphology shows well faceted crystallites with a predominance of angular shapes corresponding to <100> and <110> crystalline surfaces. The nucleation density and growth rate with argon dilution is two orders of magnitude higher than without argon deposition. The Raman spectra show a good quality film whereas XPS spectra show existence of only diamond phase.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권2호
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• pp.76-79
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• 1999

Low-hydrogenated DLC films were coated on the Mo-tip FEAs by 'layer-by-layer' process based on the plasma-enhanced CVD method. The hydrogen content in the DLC film deposited by the 'layer-by-layer' process was appeared to be remarkably lowered through SIMS analysis. Also, the low-hydrogenated DLC-coated Mo-tip FEA showed good potentiality for FED applications in terms of turn-on voltage, emission current, emission stability and light emitting uniformity.

• 한국세라믹학회지
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• 제32권6호
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• pp.697-702
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• 1995

The rough growth surfaces of diamond films fabricated by the hot filament CVD were polished using thermomechanical polishing method. And then, its application to the optical windows was discussed through the measurement of transmittance in the range of infrared radiation and analysis of surfaces structure. The results were compaerd with those of the films polished with conventional mechanicla polishing. The transmittance of the mechanically polished film reached 57~66% over the whole range from 500 to 4000 cm-1. But the transmittance of the film polished with thermomechanical polishing method was reduced below 35%. This decrease in transmittance was due to both the graphitization of diamond on the polished surface and the growth of $\beta$-SiC at diamond/Si interface during polishing. The residual Fe in hte thermomechanically polished surface was confirmed by SIMS analysis. This Fe played the role of the graphitization of near surface region of the diamond film.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1514-1515
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• 1998

Diamond thin films were deposited on n-type (100) Si wafers from $H_2-CH_4$ gas mixture by rf PACVD. Prior to deposition, mechanical scratching was done to improve density of nucleation sites with diamond paste of 3${\mu}m$. The microstructure of deposited diamond thin films was studied by using the following conditions : discharge power of 500W, $H_2$ flow rate of 50sccm, reaction pressure of 20torr, and $CH_4/H_2$ ratio of 0.3$\sim$1%. The deposited diamond thin films showed that the crystallite was increased at the lower methane concentration. The deposited thin films were characterized by Scanning Electron Microscopy. Raman Spectroscopy and Fourier-Transform Infrared Spectroscopy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1330-1332
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• 1998

Polycrystalline diamond films are deposited on a Si substrate by employing a 2.45 GHz $\mu$-wave plasma CVD system. Prior to depositing the diamond film, a DPR(diamond photo-resist) layer is coated to enhance the nucleation density. The growth rate of diamond films increases with the $\mu$-wave power and approaches to be about $1.5{\mu}m/hr$ at 1100 W. Structural properties of diamond films deposited are characterized from their SEM photographs, Raman spectra, and AFM surface images. Lager grain size, higher intensity of diamond peak, and smoother surface are observed for films deposited at a higher power. The possible mechanism on the diamond growth is also discussed to explain the experimental results.

• 한국진공학회지
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• 제3권4호
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• pp.434-441
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• 1994

메탄과 수소 혼합가스로 직류 플라즈마 화학 증착법을 이용하여 방전전류 반응압력 메탄농도 및 피착체의 온도를 변화시키면서 다이아몬드 유산탄소 박막(DLCF)을 Si(111)-웨이퍼 위에 합성하였다. 주 사전자 현미경(SEM)과 레이져 Raman 스펙트로포토메터로 확인된 양질의 DLCF를 얻은 조건은 방전전 류 반응 압력, 메탄농도 그리고 피착체의 온도가 각각 480mA, 32 Torr, 1.0 vol% 및 85$0^{\circ}C$ 였다. 이 DLCF는 대부분 sp3 탄소결합으로 된 구형의 알갱이들로 구성되어 있고 그굴절률은 2.2로 천연다이아몬 드와 비슷한 값을 가지고 있다. 또한 DLCF 성장에서 수소피복이 매우 중요한 것으로 밝혀졌다.

• 한국세라믹학회지
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• 제27권4호
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• pp.513-520
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• 1990

Diamond film was deposited on Si wafer substrate from a gas mixture of methane, hydrogen and oxygen by microwave plasma-assisted chemical vapor deposition. The effects of the pre-treatments of the substrate and of the oxygen addition on the diamond film synthesis are described. In order to obtain diamond film, the substrate was pre-treated with 3 kinds of methods. When the substrate was ultrasonically vibrated within the ethyl alcohol dispersed with 25${\mu}{\textrm}{m}$ diamond powder, the denset diamond film was deposited. Addition of oxygen in the gas mixture of methane and hydrogen improved the crystallinity of the deposited diamond film and also increased the deposition rate of the diamond film more than two times.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1542-1545
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• 2002

Experimental works were performed to implement the hetero-epitaxial growth of diamond films on the (100)- and (111)-oriented Si substrates. The deposition process used to prepare diamond films consisted of a bias-enhanced nucleation(BEN) step, accompanied with a growth step using a microwave plasma CVD system. The highly oriented diamond films were deposited under the growth condition of relatively low methane concentrations and high temperatures. Material properties and surface morphologies of deposited diamond films were improved by the addition of carburization step into the deposition process.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.870-872
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• 1999

The particles were deposited on silicon wafers at low pressure:1[torr] from $CH_4-H_2$ mixed gas by using RF plasma CVD, and were investigated by SEM and Raman spectroscopy. The results are as following; Diamond particles were synthesized under $CH_4/H_2$ concentration of 1[%], however amorphous cabon particles were synthesized over $CH_4/H_2$ concentration of 2[%]. Growth rate of diamond particle was 2.2 times: $0.8[{\mu}m/h]$ as much as that synthesized at 25[torr].

• 열처리공학회지
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• 제13권3호
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• pp.170-176
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• 2000

A novel method for improving the adhesion of diamond films on cemented carbide tool inserts has been investigated. This method is based on the formation of a compositionally graded interface by developing a microrough surface structure using a pulsed laser process. Residual stresses of diamond films deposited on laser modified cemented carbides were measured as a function of substrate roughness using micro-Raman spectroscopy. The surface morphology and roughness of diamond films and cemented carbides were also investigated at different laser modification conditions. It was found that the increasing interface roughness reduced the average residual stress of diamond films, resulting in improved adhesion of diamond films on cemented carbides.