• Journal of Ceramic Processing Research
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• 제13권spc1호
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• pp.42-46
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• 2012

The effect of the parameters for few-layered graphene growth by thermal CVD on nickel substrate was investigated. Graphene can be synthesized by using different strategies. Chemical vapor deposition (CVD) has known as one of the most attractive methods to produce graphene due to its good film uniformity, compatibility and large scale production. The control of parameters such as temperature, growth time and pressure in CVD process has been widely recognized as the most important process in graphene growth. Different carbon precursors, methane and acetylene, were introduced in the quartz tube with a variety of growth conditions. Raman spectroscopy was used to confirm the presence of a few- or multi-layered graphene.

• 한국표면공학회지
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• 제56권6호
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• pp.341-352
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• 2023

This paper reviews the potentials of a rotary chemical vapor deposition (RCVD) process for nanomaterial synthesis and coating on powder-based materials. The rotary reactor offers a significant improvement over traditional CVD methods having horizontal and fixed reaction chambers. The RCVD system yields enhanced productivity and surface coating uniformity of nanoparticles applied in various purposes, such as efficient heat dissipation, surface hardness enhancement, and enhanced energy storage performances. The effectiveness of the RCVD system would open up new possibilities in various applications because uniform coating on powder-based materials with massive productivity is inevitable to develop multi-functional materials with high reliability.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.13-13
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• 2014

그래핀은 높은 열전도도, 이동도, 물리적 강도, 화학적 안정성을 갖는 물질로써 가장 활발하게 연구가 진행되고 있는 소재이다. 하지만, 높은 품질의 그래핀을 생산하기 위한 Chemical Vapor Deposition(CVD) 그래핀 제조 방법은 높은 공정단가와 낮은 수율 문제로 적용에 어려움을 겪고 있다. 본 연구에서는 초고순도 그래핀 플레이크를 RF thermal plasma를 이용하여 제조함으로써 이러한 문제점을 해결하고자 한다.

• 한국결정성장학회지
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• 제20권3호
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• pp.133-140
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• 2010

탄소 섬유소재는 가벼우면서고 강건한 특성과 화학적 안정성 등으로 인해 항공기, 자동차, 레저, 우주항공, 풍력, 연료전지, 방위 산업 등의 분야를 비롯하여 최근에는 다양한 산업용 복합재료 및 보강용 분야에서 많이 사용되고 있다. 본 연구에서는 탄소섬유의 기능성 향상 및 다양한 응용 분야 확대를 위하여 물리적, 화학적 특성이 우수한 탄소나노튜브와 같은 다양한 탄소나노구조체를 탄소섬유상에 하이브리드화 하는 연구를 진행하였다. ELP(Electroless plating)법을 이용하여 탄소섬유 표면처리 및 촉매 입자 형성을 동시에 진행하였으며, Thermal CVD법을 이용하여 탄소나노구조체를 형성한 결과, 탄소섬유상 Pd/Ni 복합 촉매의 비율에 따라서 탄소나노튜브, 탄소나노필라멘트 등 다양한 형태의 탄소섬유상 탄소나노구조체가 형성되는 것을 알 수 있었다. Pd촉매의 비율이 높을 수록 다중벽 탄소나노튜브(Multiwall carbon naotube)의 생성 비율이 높아지고, Ni촉매의 비율이 상대적으로 증가할 수록 탄소나노필라멘트(Carbon nanofilament)의 생성 비율이 높아짐을 알 수 있었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.79-79
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• 2012

A high temperature and a low temperature plasma process technologies were developed and demonstrated for synthesis, hybrid formation, surface treatment and CVD engineering of nano powder. RF thermal plasma is used for synthesis of spherical nano particles in a diameter ranged from 10 nm to 100 nm. A variety of nano particules such as Si, Ni, has been synthesized. The diameter of the nano-particles can be controlled by RF plasma power, pressure, gas flow rate and raw material feed rate. A modified RF thermal plasma also produces nano hybrid materials with graphene. Hemispherical nano-materials such as Ag, Ni, Si, SiO2, Al2O3, size ranged from 30 to 100 nm, has been grown on graphene nanoplatelet surface. The coverage ranged from 0.1 to 0.7 has been achieved uniformly over the graphene surface. Low temperature AC plasma is developed for surface modification of nano-powder. In order to have a three dimensional and lengthy plasma treatment, a spiral type of reactor has been developed. A similar plasma reactor has been modfied for nano plasma CVD process. The reactor can be heated with halogen lamp.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.418-418
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• 2009

Vertically aligned arrays of multi-walled carbon nanotube (MWCNT) on layered Si substrates have been synthesized by water-assisted thermal chemical vapor deposition (CVD). We studied changes in growth by parameters of growth temperature, growth time, rates of gas and annealing time of catalyst. Also, We grew CNTs by adding a little amount of water vapor to enhance the growth of CNTs. $H_2$, Ar, and $C_2H_2$ were used as carrier gas and feedstock, respectively. Before growth, Fe served as catalyst, underneath which AI were coated as an underlayer and a diffusion barrier, respectively, on the Si substrate. The water vapor had a greater effect on the growth of CNTs on a smaller thickness of catalyst. When the water vapor was introduced, the growth of CNTs was enhanced than without water. CNTs grew 1.29 mm for 10 min long by adding the water vapor, while CNTs were 0.73 mm long without water vapor for the same period of time. CNTs grew up to 1.97 mm for 30 min prior to growth termination under adding water vapor. As-grown CNTs were characterized by using scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy.

• 대한전자공학회논문지
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• 제25권11호
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• pp.1329-1334
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• 1988

$NH_3-O_2$의 열반응에 의해 산화막을 성장시키는 새로운 방법을 소개하고, 기존의 건식산화방법을 이용한 $SiO_2$박막의 특성을 비교 설명하였다. $NH_3$의 유량에 따라서 박막의 성장비가 증가하고, 성장된 막의 구성성분이 건식산화때와 같음을 확인하였다. C-V특성곡선에서도 $Q_{OX}$와 $Q_{SS}$가 거의같았고 히스테리시스현상도 없었다. 또한 n-MOS트랜지스터를 제작하고 측정한 결과 $I_D$-$V_{DS}$특성곡선이 건식산화와 비교하여 우수함을 확인했다.

• 한국결정성장학회지
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• 제9권3호
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• pp.303-308
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• 1999

As a semiconductor material for electronic devices operated under extreme environmental conditions, silicon carbides(SiCs) have been intensively studied because of their excellent electrical, thermal and other physical properties. The growth characteristics of single-crystalline 4H-SiC homoepitaxial layers grown by a thermal chemical vapor deposition (CVD) were investigated. Especially, the successful growth condition of 4H-SiC homoepitaxial layers using a SiC-uncoated atmospheric pressure chamber and carried out using off-oriented substrates prepared by a modified Lely method. In order to investigate the crystallinity of grown epilayers, Nomarski optical microscopy, Raman spectroscopy, photoluninescence(PL), scanning electron microscopy(SEM) and other techniques were utilized. The best quality of 4H-SiC homoepitaxial layers was observed in conditions of growth temperature $1500^{\circ}C$ and C/Si flow ratio 2.0 of $C_{3}H_{8}\;0.2\;sccm\;&\;SiH_{4}\;0.3\;sccm$. The growth rate of epilayers was about $1.0\mu\textrm{m}/h$ in the above growth condition.

• 한국재료학회지
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• 제15권4호
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• pp.246-251
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• 2005

Plasma enhanced chemical vapor deposition(PE-CVD) method has an advantage in synthesizing carbon nanotubes(CNTs) at lower temperature compared with thermal enhanced chemical vapor deposition(TE-CVD) method. In this study, CNTs was prepared by using PE-CVD method. The growth rate of CNT was faster more than 100 times on using Invar alloy than iron as catalyst. It was found that chrome silicide was formed at the interface between chrome layer and silicon substrate which should be considered in designing process. Nanoparticles of Invar catalyst were found oxidized on their surfaces with a depth of 10 m. Microstructure was analyzed by scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, and energy dispersive x-ray spectrometry. Based on the result of analysis, growth mechanism at an initial stage was suggested.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.149-149
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• 2016

Ceramic is widely known material due to its outstanding mechanical property. Besides, Zirconia(ZrO2) has a low thermal conductivity so it is advantage in a heat insulation. Because of these superior properties, ZrO2 is attracted to many fields using ultra high temperature for example vehicle engines, aerospace industry, turbine, nuclear system and so on. However brittle fracture is a disadvantage of the ZrO2. In order to overcome this problem, we can make the ceramic materials to the forms of ceramic nanoparticles, ceramic nanowhiskers and these forms can be used to an agent of composite materials. In this work, we selected Au catalyzed Vapor-Liquid-Solid mechanism to synthesize ZrO2 nanowhiskers. The ZrO2 whiskers are grown through Hot-wall Chemical Vapor Deposition(Hot wall CVD) using ZrCl4 as a powder source and Au film as a catalyst. This Hot wall CVD method is known to comparatively cost effective. The synthesis condition is a temperature of $1100^{\circ}C$, a pressure of 760torr(1atm) and carrier gas(Ar) flow of 500sccm. To observe the morphology of ZrO2 scanning electron microscopy is used and to identify the crystal structure x-ray diffraction is used.