• Journal of Magnetics
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• 제11권3호
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• pp.111-114
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• 2006

We electroplated copper-cobalt thin films on a silicon substrate, which had 150 nm thick copper seed layer. The adhesion between the two metallic layers could be increased by utilizing a proper organic additive, pulse plating technique, and high temperature annealing. The thin films exhibited columnar growth of the deposits and enhanced adhesion. This is attributed to the grain growth mechanism introduced by the additive and annealing.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 춘계학술발표회 초록집
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• pp.111-113
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• 2007

Thermal conductivities of copper thin films on silicon wafer was obtained from temperature distribution on the surface of wafer measured by radiation thermometry, when sample was heated with constant temperature ate the both ends in a vacuum and dissipate heat by radiation heat transfer into an environment.

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.445-449
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• 1991

A series of trisilaalkanes has been prepared in high yields by the direct reaction of ${\alpha}$ -chloromethylsilanes with metallic silicon in the presence of copper catalyst using the stirred reactor equipped with a spiral band agitator at the carefully controlled temperature between $280^{\circ}C$ and $340^{\circ}C.$ Disilaalkane compounds were obtained as the minor products. Cadmium was found to be a good promotor for the reactions, while zinc was an inhibitor.

• 한국세라믹학회지
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• 제28권9호
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• pp.667-674
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• 1991

In this study, Kaolin was carbonized at 1300~175$0^{\circ}C$ and its constituent mineral change was investigated. Carbonized kaolin at 1$650^{\circ}C$ was mixed with metallic silicon, formed and nitrified at 135$0^{\circ}C$ in N2-NH3 atmosphere. Properties of this product such as porosity, bulk density, MOR, nitrization rate and oxidation resistence were measured, and its mineralogical changes were investigated by XRD. The results were as follows; 1) $\beta$-SiC was initially synthesized at 150$0^{\circ}C$, and its amount was continuously increased with reaction temperature to 1$700^{\circ}C$. 2) At 1$600^{\circ}C$, mullite was rapidly decomposed and the amounts of $\beta$-SiC and $\alpha$-Al2O3 were increased simultaneously. 3) By adding alkali to kaolin, the decomposition temperature of mullite was dropped approximately 10$0^{\circ}C$, but the amount of $\alpha$-SiC was increased. 4) The highest values of their nitrization rate and MOR were obtained at the specimen of 35 wt% metallic silicon in nitrization reaction. 5) It seems that increment of $\alpha$-Si3N4 and $\alpha$-Al2O3 phase during nitrization was due to the decomposition of Al4SiC4 existed in carbonized kaolin. 6) Si3N4 bonded SiC-Al2O3 composite were fabricated from kaolin at relatively low temperature (135$0^{\circ}C$).

• 한국세라믹학회지
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• 제50권6호
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• pp.402-409
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• 2013

The objective of this study was to develop a synthesis process for ${\beta}$-SiC powders to reduce the synthesis temperature and to control the particle size and to prevent particle agglomeration of the synthesized ${\beta}$-SiC powders. A phenol resin and TEOS were used as the starting materials for the carbon and Si sources, respectively. $SiO_2$-C hybrid precursors with various C/Si mole ratios were fabricated using a conventional sol-gel process. ${\beta}$-SiC powders were synthesized by a carbothermal reduction process using $SiO_2$-C hybrid precursors with various C/Si mole ratios (1.6 ~ 2.5) fabricated using a sol-gel process. In this study, the effects of excess carbon and the addition of Si powders to the $SiO_2$-C hybrid precursor on the synthesis temperature and particle size of ${\beta}$-SiC were examined. It was found that the addition of metallic Si powders to the $SiO_2$/C hybrid precursor with excess carbon reduced the synthesis temperature of the ${\beta}$-SiC powders to as low as $1300^{\circ}C$. The synthesis temperature for ${\beta}$-SiC appeared to be reduced with an increase of the C/Si mole ratio in the $SiO_2$-C hybrid precursor by a direct carburization reaction between Si and excess carbon.

• 자원리싸이클링
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• 제21권5호
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• pp.31-37
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• 2012

실리콘 웨이퍼공정에서 발생하는 실리콘 슬러지로부터 실리콘 및 탄화규소를 분리한 다음, 전해법으로 원소형태의 실리콘을 회수하는 연구를 수행하였다. 실리콘 슬러지의 주요 불순물은 절삭유, 금속불순물, 실리콘 및 실리콘 카바이드를 들 수 있다. 기계적 선별법으로 분리한 실리콘, 탄화실리콘 복합물을 $1000^{\circ}C$에 1시간동안 염화 배소하여 응축하고 회수한 사염화실리콘을 이온성액체인 $[Bmpy]Tf_2N$에 용해하여 전해액으로 사용하였다. 순환전위법으로부터 $[Bmpy]Tf_2N$의 안정한 전압구간과 사염화실리콘을 용해한 $[Bmpy]Tf_2N$ 전해액에서 실리콘의 환원으로 추정되는 환원피크를 얻을 수 있었다. 정전위법(-1.9 V vs. Pt-QRE)에서 1시간동안 금 전극 상에 전해한 다음, 전극표면을 XRD, SEM-EDS 및 XPS 분석을 통하여 실리콘이 원소형태로 전착되었음을 확인하였으며, 미량의 산소가 검출되는 것은 분석과정에서 시편이 공기 중에 노출되었기 때문으로 판단된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.75-75
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• 2015

Strong interactions between electromagnetic radiation and electrons at metallic interfaces or in metallic nanostructures lead to resonant oscillations called surface plasmon resonance with fascinating properties: light confinement in subwavelength dimensions and enhancement of optical near fields, just to name a few [1,2]. By utilizing the properties enabled by geometry dependent localization of surface plasmons, metal photonics or plasmonics offers a promise of enabling novel photonic components and systems for integrated photonics or sensing applications [3-5]. The versatility of the nanoplasmonic platform is described in this talk on three folds: our findings on an enhanced ultracompact photodetector based on nanoridge plasmonics for photonic integrated circuit applications [3], a colorimetric sensing of miRNA based on a nanoplasmonic core-satellite assembly for label-free and on-chip sensing applications [4], and a controlled fabrication of plasmonic nanostructures on a flexible substrate based on a transfer printing process for ultra-sensitive and noise free flexible bio-sensing applications [5]. For integrated photonics, nanoplasmonics offers interesting opportunities providing the material and dimensional compatibility with ultra-small silicon electronics and the integrative functionality using hybrid photonic and electronic nanostructures. For sensing applications, remarkable changes in scattering colors stemming from a plasmonic coupling effect of gold nanoplasmonic particles have been utilized to demonstrate a detection of microRNAs at the femtomolar level with selectivity. As top-down or bottom-up fabrication of such nanoscale structures is limited to more conventional substrates, we have approached the controlled fabrication of highly ordered nanostructures using a transfer printing of pre-functionalized nanodisks on flexible substrates for more enabling applications of nanoplasmonics.

• 한국결정성장학회지
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• 제15권2호
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• pp.57-60
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• 2005

[ $SiO_2$ ]로 산화된 웨이퍼 위에 상압화학기상증착 기술로 반도체 탄소나노튜브를 성장했으며, 이 나노튜브의 전기적 특성을 조사하였다. 전기적 특성은 반도체 탄소나노튜뷰를 $300^{\circ}C$, 대기 중에서 산화 열처리 시간을 변화시키면서 상온대기에서 측정하였다. 반도체 탄소나노튜브는 $300^{\circ}C$에서 산화 열처리 시간을 증가할수록 점차적으로 금속 탄소나노튜브로 변형되는 것을 보았다. 탄소나노튜브는 $300^{\circ}C$, 대기에서 6시간 동안 산화 열처리 후 표면의 일부가 없어지는 현상을 투과 전자현미경으로 확인하였다.

• Carbon letters
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• 제27권
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• pp.35-41
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• 2018

Surfactant-wrapped separation methods of metallic and semiconducting single-walled carbon nanotubes (SWCNTs) can result in large changes in intrinsic physical and chemical properties due to electronic interactions between a nanotube and a surfactant. Our approach to synthesize SWCNTs with an electronic feature relied on utilizing carbon nanorings, [n] cycloparaphenylenes ([n]CPPs), which are the fundamental unit of armchair type SWCNTs (a-SWCNTs) that possess a metallic feature without any surfactants. To obtain long tubular structures from [n]CPPs, the host-guest complexes formed with well-aligned [n]CPP hosts and various fullerene guests on a silicon substrate were pyrolyzed under an ethanol gas flow at a high temperature with focused-ultraviolet laser irradiation. The pyrolyzed [n]CPPs were observed to transform from nanorings to tubular structures with 1.5-1.7 nm diameters corresponding to the employed diameter of [n]CPPs. Our approach suggests that [n]CPPs are useful for structure-controlled synthesis of SWCNTs.

• Metals and materials international
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• 제24권6호
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• pp.1256-1261
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• 2018

Both thermoplastic formability and electrical conductivity of Al-Ni-Y metallic glass with 12 different compositions have been investigated in the present study with an aim to apply as a functional material, i.e. as a binder of Ag powders in Ag paste for silicon solar cell. The thermoplastic formability is basically influenced by thermal stability and fragility of supercooled liquid which can be reflected by the temperature range for the supercooled liquid region (${\Delta}T_x$) and the difference in specific heat between the frozen glass state and the supercooled liquid state (${\Delta}C_p$). The measured ${\Delta}T_x$ and ${\Delta}C_p$ values show a strong composition dependence. However, the composition showing the highest ${\Delta}T_x$ and ${\Delta}C_p$ does not correspond to the composition with the highest amount of Ni and Y. It is considered that higher ${\Delta}T_x$ and ${\Delta}C_p$ may be related to enhancement of icosahedral SRO near $T_g$ during cooling. On the other hand, electrical resistivity varies with the change of Al contents as well as with the change of the volume fraction of each phase after crystallization. The composition range with the optimum combination of thermoplastic formability and electrical conductivity in Al-Ni-Y system located inside the composition triangle whose vertices compositions are $Al_{87}Ni_3Y_{10}$, $Al_{85}Ni_5Y_{10}$, and $Al_{86}Ni_5Y_9$.