• Journal of the Korean Ceramic Society
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• v.31 no.3
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• pp.257-264
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• 1994

The objectives of this study were to develop the low pressure chemical vapor deposition(LPCVD) process of SiC and to fabricate pure and dense SiC layer onto graphite substrate at low temperature. The deposition experiments were performed using the MTS-H2 system (30 torr) in the deposition temperature ranging from 100$0^{\circ}C$ to 120$0^{\circ}C$. The deposition rate of SiC was increased with the temperature. The rate controlling step can be classified from calculated results of the apparent thermal activation energy as follows; surface reaction below 110$0^{\circ}C$ and gas phase diffusion through a stagnant layer over 110$0^{\circ}C$. The deposited layer was $\beta$-SiC with a preferred orientation of (111) and the strongly faceted SiC deposits were observed over 115$0^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.31 no.8
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• pp.927-933
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• 1994

Alumina composite membranes were prepared by chemical vapor deposition (CVD) using aluminum-tri-isopropoxide as a precursor. Porous alumina supports were used in deposition, which were in disk shape with mean pore diameter of 0.1 ${\mu}{\textrm}{m}$ and prepared by slip-coasting process. film deposition morphology on porous support was simulated through depositing alumina film on polycrystalline silicon pattern, and its step coverage observed by SEM showed one deviated from uniform step coverage. N2 permeability through composite membranes and the pressure dependence decreased as the deposition time increased. Initially, the N2 permeability of the top layer was tend to decrease rapidly, and then the degree of decrease in N2 permeability was tend to diminish with deposition time. The N2 permeability increased with heat treatment temperature and the crack was generated in top layer at 100$0^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.489-497
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• 1995

The DDS((CH3)2SiCl2)＋H2 gas mixture, where C atoms exist in excess in the molecules, was used for chemical vapor deposition of SiC in order to prevent codeposition of free Si in MTS(Ch3SiCl3)＋H2 system. The deposition rate was more rapid than MTS, however differ from that of MTS, it decreased after shwoing a maximum at 140$0^{\circ}C$. The stoichiometry was highly improved by using the DDS as a precursor, although there exist a little pyrolytic C at 150$0^{\circ}C$. The preferred orientation was (220) in MTS, however, it changed to (111) in DDS. The microstructure of the layer deposited at lower temperature were dense, however it grew coarse with the increase in the temperature.

• Journal of Sensor Science and Technology
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• v.22 no.3
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• pp.175-180
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• 2013

This paper describes the characteristics of cubic silicon carbide (3C-SiC) films grown on a carbonized Si(100) substrate, using hexamethyldisilane (HMDS, $Si_2(CH_3)_6$) as a safe organosilane single precursor in a nonflammable $H_2$/Ar ($H_2$ in Ar) mixture carrier gas by atmospheric pressure chemical vapor deposition (APCVD) at $1280^{\circ}C$. The growth process was performed under various conditions to determine the optimized growth and carbonization condition. Under the optimized condition, grown film has a single crystalline 3C-SiC with well crystallinity, small voids, low residual stress, low carrier concentration, and low RMS. Therefore, the 3C-SiC film on the carbonized Si (100) substrate is suitable to power device and MEMS fields.

• Composites Research
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• v.18 no.5
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• pp.27-33
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• 2005

In this research, the mathematical modelling of the pulse-CVI (Chemical Vapor Infiltration) for the preparation of siliconcarbide/carbon composite. Each pulse consists with the gas injection time, the reaction time and the evacuation time. Effects of the reaction time and the evacuation time were studied. Additionally, the effects of the reactant concentration and the pressure were observed. The benefits of the pulse-CVI such as the uniform infiltration of siliconcarbide into the carbon preform and the short reaction time were certified.

• Journal of the Korean Vacuum Society
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• v.1 no.2
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• pp.277-285
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• 1992

플라즈마 화학기상증착법과 저압 화학기상증착법을 사용하여 실리콘 기판 위에 텅 스텐 박막을 증착하였다. 반응기체로 WF6를 사용하였으며 환원기체로는 SiH4를 사용하였다. 플라즈마 증착법에 의한 텅스텐 박막의 성장은 환원기체의 유무에 상관없이 주로 기상 반응 에 의한 텅스텐 덩어리들의 증착에 의하여 이루어졌으며 비교적 균일도가 낮은 박막표면을 이루었다. 저압 화학증착법의 경우 환원기체를 사용하지 않았을 때에는 실리콘 기판에 의한 제한된 환원반응에 의해 텅스텐이 증착되었으나, 환원기체를 사용했을 때에는 초기의 실리 콘 기판에 의한 환원반응과 이어 일어나는 SiH4 기체와의 불균일계 환원반응의 두 단계반응 에 의하여 텅스텐 박막 증착이 이루어졌다. 저압 화학증착법의 경우 텅스텐 박막의 특성은 플라즈마 증착법에서 보다 우수하였으며 박막 성장은 island by island 양식을 따르는 것으 로 추정되었다. 박막은 $\alpha$-W의 체심입방 구조로 이루어졌으며 박막이 성장함에 따라 단결정 구조가 증가하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.129.2-129.2
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• 2011

본 연구에서는 a-Si:H/c-si 구조의 이종접합 태양전지의 p a-Si:H 에미터 층의 박막 조건에 따라 태양전지 특성을 연구하였다. p, n-layer는 PECVD (Plasma-enhanced chemical vapor deposition) i-layer는 HWCVD(Hot wire chemical vapor deposition), ITO는 RF 마그네트론 스퍼터링법으로 제작하였다. p-layer의 도핑 농도, 기판 증착 온도, 증착 높낮이에 따라 특성을 비교 분석 하였다. QSSPC로 minority carrier life time, 자외 가시선 분광분석 장치로 투과 반사도를, Ellipsometer로 흡수 계수, 두께, FTIR로 막의 구성요소 등의 변화를 조사하여 개선된 p a-Si:H의 특성이 이종접합 태양전지에서 효율향상에 영향을 주는지 Photo IV와 EQE를 통하여 조사하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.562-565
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• 2001

In this paper, novel device structures in order to realize ultra fast and ultra small silicon devices are investigated using ultra-high vacuum chemical vapor deposition(UHVCVD) and Excimer Laser Annealing (ELA). Based on these fundamental technologies for the deep sub-micron device, high speed and low power devices can be fabricated. These junction formation technologies based on damage-free process for replacing of low energy ion implantation involve solid phase diffusion and vapor phase diffusion. As a result, ultra shallow junction depths by ELA are analyzed to 10~20nm for arsenic dosage(2${\times}$10$\_$14//$\textrm{cm}^2$), exciter laser source(λ=248nm) is KrF, and sheet resistances are measured to 1k$\Omega$/$\square$ at junction depth of 15nm and realized sub-50nm n-MOSFET.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.935-938
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• 2001

Carbon nanotubes(CNTs) was successfully grown on Ni coated silicon wafer substrate by applying PECVD technique(Plasma Enhanced Chemical Vapor Deposition). As a catalyst, Ni thin film of thickness ranging from 15∼30nm was prepared by electron beam evaporator method. In order to find the optimum growth condition, the type of the gas mixture such as C$_2$H$_2$-NH$_3$was systematically investigated by adjusting the gas mixing ratio in temperature of 600$^{\circ}C$ under the pressure of 0.4 torr. The diameter of the grown CNTs was 40∼150nm. As NH$_3$etching time increased the diameters of the nanotubes decreased whereas the density of nanotubes increased. TEM images clearly demonstrated synthesized nanotubes was multiwalled. We investigated electrical properties for the application of FED.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.131-134
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• 2001

Vertically aligned carbon nanotubes are grown on iron-deposited silicon oxide substrates by thermal chemical vapor deposition of acetylene gas at the temperature range 750∼950$^{\circ}C$. As the growth temperature increases from 750 to 950$^{\circ}C$, the growth rate increases by 4 times and the average diameter also increases from 30 nm to 130 nm while the density increases progresively with the growth temperature and a higher degree of crystalline perfection can be achieved at 950$^{\circ}C$. This result demonstrates that the growth rate, diameter, density, and crystallinity of carbon nanotubes can be controlled with the growth temperature.