• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.839-844
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• 2002

This letter focuses on the liquid crystal alignment characteristics according to the properties of hydrogenated amorphous carbon(a-C:H) thin film deposited by RPECVD(Remote Plasma Enhanced Chemical Vapor Deposition) method using $C_2H_2$ and He gases. The properties of the deposited thin films were controlled by the ion beam irradiation time and ion beam energy. The results show that not ion beam energy but ion beam irradiation time plays an important role in the properties of a-G:H thin films. As the ion beam irradiation time increases, not only the sp2 concentration in a-G:H thin films but also liquid crystal pretilt angle was varied.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1211-1214
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• 2003

The film is prepared by electron cyclotron resonance chemical vapor deposition (ECRCVD) employing CH$_4$ and H$_2$ gases. It is deposited by the control of microwave plasma power, gas flow ratio, deposition pressure, and In-situ thermal treatment temperature. The structure of a-C:H (hydrogenated amorphous carbon) thin film is analysed by FT-IR spectroscopy. The fraction sp$^3$ versus sp$^2$ bonding is very important to clear up the surface and interrace of a-C:H film properties such as nano-scale friction behavior. The sp$^3$ versus sp$^2$ bonding of a-C:H thin film is dependent on the deposition conditions, therefore. nano-scale friction behavior is dependent on the deposition conditions.

• Journal of Surface Science and Engineering
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• v.29 no.6
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• pp.648-653
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• 1996

Hydrogenated amorphous carbon(a-C:H) films are prepared by rf plasma CVD in a $CH_4$ source gas system diluted with Ar of $H_2$. The spectra of emissive and reactive species in the plasma are detected using in stiu optical emission spectroscopy. Inaddition, the relationship between the film properties which can be varied by the deposition parameters and the Raman spectra is studied. In the $CH_4/H_2$ gas system, the emission intensities of CH and $H \tau$ decrease and those of $H \alpha$, $H \beta$, $C_2$ and Ar increase with increasing $H_2$ concentration, The formation of $C_2$ and CH in the $CH_4/Ar/H_2$ gas system is greatly suppressed by hydrogen addition and the excess of hydrogen addition is found to form graphite structure. The $C_2$ formation in the gas phase enhances a-C:H film formation.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.142-142
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• 2017

High Flory-Huggins interaction parameter (${\chi}$)를 가지는 polystyrene-block-dimethylsiloxane (PS-b-PDMS)는 초미세 패턴 제작과 우수한 defect density, 우수한 edge roughness 특성으로 향상된 패턴을 제공한다는 점에서 반도체 분야에서 많은 연구가 되고 있다. 하지만, PS와 PDMS 사이에 존재하는 큰 surface tension의 차이로 인해 PDMS는 PS와 air 사이에서 segregate되기 때문에 수직배향에 불리하여 high aspect ratio (HAR)을 가지는 cylinder, lamellar 패턴 제작에 있어 큰 어려움을 가진다. 본 연구에서는 이러한 문제를 해결하기 위해, PS-b-PDMS BCP 패턴과 하부 실리콘 기판 사이에 amorphous carbon layer (ACL)를 삽입하여 효과적으로 pattern transfer하는 공정을 연구하였다. 플라즈마를 이용하여 무한대에 가까운 etch selectivity를 가지는 식각 공정을 개발함으로써 낮은 aspect ratio를 가지는 PS-b-PDMS BCP 패턴의 한계점을 극복하였다. Large-x value를 가지는 BCPs를 이용하여도 매우 높은 aspect ratio를 가지면서 동시에 pattern quality를 향상시킬 수 있는 plasma process를 제시하였다.

• 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 Sensor Science and Technology
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• v.21 no.5
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• pp.385-388
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• 2012

This paper describes the synthesis and characterization of graphene by RTA process. Amorphous 3C-SiC were deposited using APCVD for carbon source and Ni layer were employed for transition layer. Various parameters of the ramping speed, the annealing time and the cooling speed are evaluated for the optimized combination allowed for the reproducible fabrication of graphene using 3C-SiC thin film. For analysis of crystalline Raman spectra was employed. Transferred graphene shows a high IG/ID ratio of 2.73. SEM and TEM images show the optical transparency and 6 carbon network, respectively. Au electrode deposited on the transferred graphene shows linear I-V curve and its resistance is 358 ${\Omega}$.

• Journal of Surface Science and Engineering
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• v.43 no.1
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• pp.36-40
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• 2010

The SiO vapor that was generated from a mixture of Si and $SiO_2$ was reacted at $1350^{\circ}C$ for 2 h under vacuum with carbon nanofibers to produce SiC nanofibers having an average diameter of 100~200 nm. In order to understand the gas corrosion behavior, SiC nanofibers were exposed to air up to $1000^{\circ}C$. SiC oxidized to amorphous $SiO_2$, but its oxidation resistance was inferior unlike bulk SiC, because of high surface area of nanofibers. When SiC nanofibers were exposed to Ar-1% $SO_2$ atmosphere, SiC oxidized to amorphous $SiO_2$, without forming $SiS_2$, owing to the thermodynamic stability of $SiO_2$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.129-130
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• 2007

3,3-Dimethyl-1-butene ($C_6H_{12}$) monomer를 이용하여 RF power와 압력에 따라 막을 증착하였다. Power/pressure (W/Torr)가 증가할수록 증착된 비정질 탄소막은 FT-IR 스펙트럼에서 $CH_x$ (at around $2900cm^{-1}$)는 감소하였지 만 elastic modulus는 증가하는 것으로 나타났다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.185-186
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• 2007

3,3-Dimethyl-1-butene ($C_6H_{12}$) monomer를 이용하여 RF power와 압력에 따라 막을 증착하였다. 증착된 막은 power/pressure (W/Torr)가 증가할수록 비정질 탄소막은 FT-IR 스펙트럼에서 $CH_x$ (at around $2900cm^{-1}$)는 감소하였고, n과 k값은 증가하는 것으로 나타났다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.104-105
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• 2007

3,3-Dimethyl-1-butene($C_6H_{12}$) monomer를 이용하여 RF power와 압력에 따라 증착된 막의 refractive index와 extinction coefficient를 알아보았다. 증착된 막의 n & k는 power/pressure가 증가할수록 증가하였으며, Ar으로 증착된 막이 더 낮은 값을 갖는 것으로 나타났다.