• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.590-590
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• 2013

Direct growth of graphene using CVD method has been done on CVD grown boron nitride substrate. From the SEM image, we have shown that the size of grain of graphene could be clearly controlled by varying the amount of injected hydrocarbon. To convince the existence of graphene on boron nitride, XPS and Raman has been checked. Both B1s and N1s peaks in XPS spectra and the Raman peak around 1,370 $cm^{-1}$ demonstrated that boron nitride did remain after high temperature treatment during the graphene growth process. And along the graphene grain boundary, the Raman fingerprint of graphene was neatly appeared.

• 한국의류학회지
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• 제23권5호
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• pp.694-702
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• 1999

By using commercial available electromagnetic interference (EMI) shielding fabrics, EMI shielding effectiveness(SE) and the physical properties were investigated. Thirteen specimens were chosen six fabrics were non-electrolytic plated with Cu, six plated with Cu+Ni and one plated with Ni, SE was measured by RF Impedance Analyzer HP4291A(Hewlett Co, Ltd)at the frequency of 100MHz-1.8GHz. The results showed that the commercial EMI shielding fabrics provided SE values over 30dB at the frequency of 100MHz-1.8GHz. Fabrics plated with Cu showed more effective shielding than those plated with Ni. The thickness of coating and fabric count were also influential factors on SE. Tensile properties were acceptable for lining fabrics but water vapor transport properties indicated that the better treatment condition were suggested to improve comfort properties.

• Carbon letters
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• 제6권4호
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• pp.227-233
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• 2005

Carbonization products C1, C2, C3, C4 and C5 were prepared by the carbonization of date pit in limited air, at 500, 600, 700, 800 and $1000^{\circ}C$, respectively. C1-V-600, C3-V-600, C1-V-1000 and C3-V-1000 were prepared by thermal treatment of C1 and C3 under vacuum at 600 and $1000^{\circ}C$. The textural properties were determined from nitrogen adsorption at 77 K and from carbon dioxide adsorption at 298 K. The surface pH, the FTIR spectra and the acid and base neutralization capacities of some carbons were investigated. The amounts of surface oxygen were determined by out-gassing the carbon-oxygen groups on the surface as $CO_2$ and CO. The adsorption of water vapor at 308 K on C1, C2, C3 and C4 was measured and the decomposition of $H_2O_2$ at 308 K was also investigated on C1, C2, C3, C4 and C5. The surface area and the total pore volume decreased with the rise of the carbonization temperature from 500 to $1000^{\circ}C$. The adsorption of water vapor is independent on the textural properties, while it is related to the amount of acidic carbon-oxygen groups on the surface. The catalytic activity of $H_2O_2$ decomposition does not depend on the textural properties, but directly related to the amount of basic carbon-oxygen complexes out-gassed as CO, at high temperatures.

• 대한전자공학회논문지SD
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• 제37권3호
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• pp.14-19
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• 2000

Seed crystal 로 bare (0001) 사파이어 기판을 사용하여 hydride vapor Phase epitaxy (HVPE)법을 이용하여 free-standing GaN 단결정기판을 성장시켰다. 일정한 두께의 GaN막을 성장한 후 사파이어 기판을 mechanical polishing 작업으로 제거하여 두께 200 ㎛, 10×10 ㎛ 크기의 free-standing GaN 기판을 얻을 수 있었으며, 성장 전 GaCl 전처리를 수행함으로써 crack이 없는 기판을 제작할 수 있었다. 이렇게 제작된 free-standing GaN 기판의 특성을 SiO/sub 2/ patterned sapphire위에 LEO (Lateral Epitaxial Overgrowth) 방법으로 성장된GaN박막과 double crystal x-ray diffraction (DC-XRD), cathode-luminescence (CL) 및 photoluminescence (PL) 방법으로 특성을 비교하였다.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.687-693
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• 2004

Composite membranes with a titania layer were prepared by soaking-rolling method with the titania sol of nanoparticles formed in the sol-gel process and investigated regarding the vapor permeation of various organic mixtures. The support modification was conducted by pressing $SiO_2$ xerogel of 500 nm in particle size under 10 MPa on the surface of a porous stainless steel (SUS) substrate and designed the multi-layered structure by coating the intermediate layer of ${\gamma}-Al_2O_3$. Microstructure of titania membrane was affected by heat-treatment and synthesis conditions of precursor sol, and titania formed at calcination temperature of 300$^{\circ}C$ with sol of [$H^+$]/[TIP]=0.3 possessed surface area of 210 $m^2$/g, average pore size of 1.25 nm. The titania composite membrane showed high $H_2/N_2$ selectivity and water/ethanol selectivity as 25-30 and 50-100, respectively. As a result of vapor permeation for water-alcohol and alcohol-alcohol mixture, titania composite membrane showed water-permselective and molecular-sieve permeation behavior. However, water/methanol selectivity of the membrane was very low because of chemical affinity of permeants for the membrane by similar physicochemical properties of water and methanol.

• 한국자기학회지
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• 제21권5호
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• pp.185-192
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• 2011

박막제조 기술은 과학 기술의 기초가 되는 분야로 양질의 박막을 제조하기 위한 다양한 노력이 경주되고 있다. 박막제조는 표면개질과 함께 표면처리 기술의 한 분야이며 이중 진공증착으로 알려진 물리증착법과 화학증착법은 현대의 과학기술 연구는 물론 산업적으로 폭넓게 이용되는 박막제조 기술 중의 하나이다. 진공증착을 이용한 박막제조 기술은 나노 기술의 등장과 함께 비약적인 발전을 이루었으며 자연모사와 완전화 박막의 제조, 융복합 공정을 이용한 기능성 코팅과 Engineered Structure 구현 그리고 초고속 증착과 원가 저감 기술의 실현이 주요 이슈로 등장하고 있다. 본 논문에서는 물리증착법과 화학증착법을 중심으로 박막제조 기술의 종류와 원리를 설명하고 박막제조 기술의 최신 동향과 기술적 이슈 및 향후 전망에 대해 기술한다.

• Korean Chemical Engineering Research
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• 제45권2호
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• pp.149-154
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• 2007

나노임프린트 공정기술은 나노구조물이 패턴된 스템프(혹은 몰드)를 이용하여 적절한 기판 위에 나노구조물을 복제하여 패턴을 전사하는 기술이다. 효과적인 나노임프린트 공정을 위해서는 몰드의 이형처리뿐 아니라 반대쪽의 기질과 레지스트 사이에 접착력 증가(adhesion promoter) 처리가 매우 중요한 역할을 한다. 본 연구에서는 자기조립 실란커플링제의 기상증착을 이용하여 나노임프린트 공정에서 사용되는 접착 증가막 및 표면처리 방법을 비교 분석 하였다. 이를 위해서 평탄화층(DUV-30J), 산소 플라즈마 처리, 실란커플링제 자기조립막이 비교되었다. 실란커플링제 자기조립막이 형성된 실리콘 표면은 전체적으로 나노 두께의 균일한 막이 형성되며 임프린트시 구조물들을 정밀하게 전사하였으며 3-acryloxypropyl methyl dichlorosilane(APMDS)을 이용한 자기조립막(SAMs) 처리가 평탄화층과 산소 플라즈마 처리보다 강한 접착력을 가지고 있어 나노임프린트 공정에 적합함을 알 수 있었다.

• 한국대기환경학회지
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• 제19권1호
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• pp.101-112
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• 2003

Biological methods are frequently used for treatment of contaminated air, containing volatile organic compounds and odor compounds in low concentrations and high flow rate of air streams. For more than 20 years. biofilter has been recognized as a cost effective technology for the purification of contaminated air. Most commercial applications before 1990 were for control of odors. In the past decades major progress has been accomplished in the development of vapor phase bioreactor. in particular biotrickling filers. Biotrickling filters are more complex than biofilters. but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. While the level of understanding of biotrickling filtration process for VOCs still remains limited. the evidence success of biotreatment of VOC in air resulted in pursuing active research. This paper presents fundamental and practical aspert of VOCs treatment from air in biotrickling filter. Special emphasis is given to the operating parameters and the factors influencing performance for biotrickling filter.

• 대한전자공학회논문지
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• 제11권1호
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• pp.8-14
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• 1974

GaAs을 여러가지 As의 중기압하에서 열처리를 하여 그의 특성이 어떻게 변했는가를 조사하였으며 열처리과정에서 생기는 결함들이 어떤것이며 그의 성질이 어떤것인가를 알아 보았다. 아울러 As GaAs의 P-N 접합을 만들어 그의 P-V 특성을 측정하였다.

• 열처리공학회지
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• 제6권4호
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• pp.223-229
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• 1993

Extensive reseach has been performed on the process condition-micro structure-stress relations of TiN film. The various proposed models are mainly base on physical vapor deposition processes. Especially the study on the micro-structure and deposition condition has not been sufficient in TiN deposited by PECVD. In this study, therefore, we discussed the morphological changes of TiN films by PECVD with different temperature and pressure, and compared it with the structure zone model. We could find out that the oxygen and chlorine contents and the texture coefficient increased with deposition temperature, and the morphology of TiN transformed from Zone 1 to Zone T, but deposition pressure didn't remarkly affected.