• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 제35회 춘계학술대회
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• pp.40-44
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• 2002

The motivation of this work is to use SAM(Self-Assembled Monolayer) for developing a rapid and flexible non-photolithographic nano-structure fabrication technique which can be utilized in micro-machining of metals as well as silicon-based materials. The fabrication technique implemented in this work consists of a two-step process, namely, mechanical scribing followed by chemical etching. From the experimental results, it was found that thiol on copper surface could be removed even under a few nN normal load. The nano-tribological characteristics of thiol-SAM on various metals were largely dependent on the native oxide layer of metals. Based on these findings, nano-patterns with sub-micrometer width and depth on metal surfaces such as Cu, Au and Ag could be obtained using a diamond-coated tip.

• 전자공학회논문지A
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• 제28A권11호
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• pp.887-893
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• 1991

To take advantage of Ti-polycide, when it is contacted with both n+ and p+ active area of silicon, the effects of BF$_2$ on the formation of Ti-silicide were investigated with RTA temperature and dopant concentration. The intermediate phase C49 TiSi$_2$ appeared at $650^{\circ}C$ and the stable phase C54 TiSi2 was formed at $700^{\circ}C$. And the formation of Ti-silicide was hindered by BF$_2$ doping and this trend was decreased with increasing temperature. The out-diffusion phenomena of BF$_2$ into Ti silicide were not observed. And significantly, the native oxide was a chief factor preventing the formation of Ti-silicides.

• Journal of Electrical Engineering and information Science
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• 제3권1호
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• pp.110-116
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• 1998

A single-crystalline epitaxial film of GaAs has been grown on Si using a gs assisted-ionized vapour beam eptaxial technique. The native oxide layer on the silicon substrate was removed at 550$^{\circ}C$ by use of an accelerated arsenic ion beam, instead of a high-temperature desorption. During the growth the substrate temperature was maintained at 550$^{\circ}C$. Transmission electron microscopy and electron diffraction data suggest that the GaAs layer is an epitaxially grown single-crystalline layer. The possibility of growing device quality GaAs on Si is able demonstrated through fabrication of GaAs MODFET on Si substrates.

• 한국전기전자재료학회논문지
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• 제23권4호
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• pp.343-346
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• 2010

We have investigated growth of CdTe thin films by using (As, GaAs) buffer layers for application of large scale IR focal plane arrays(IFPAs). Buffer layers were grown by molecular beam epitaxy(MBE), which reduced the lattice mismatch of CdTe/Si and prevented native oxide on Si substrates. CdTe thin films were grown by metal organic chemical deposition system(MOCVD). As a result, polycrystalline CdTe films were grown on Si(100) and arsenic coated-Si(100) substrate. In other case, single crystalline CdTe(400) thin film was grown on GaAs coated-Si(100) substrate. Moreover, we observed hillock structure and mirror like surface on the (400) orientated epitaxial CdTe thin film.

• 전자공학회논문지A
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• 제28A권10호
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• pp.814-820
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• 1991

TaSi$_2$ was formed by rapid thermal annealing(RTA) on BF$_2$ doped single crystalline silicon substrates. The formation and various properties of TaSi$_2$ have been investigated by using 4-point probe, HP414, XRD, and SEM. And the redistribution of boron with RTA has been observed by SIMS. Implanted boron was diffused out into the TaSi$_2$ for RTA temperature but did not significantly affect the formation temperature of TaSi$_2$. Also, the contact resistance for TaSi$_2$/p$^{+}$ region had a low value 22$\Omega$, at contact size of 0.9$\mu$m, and the native oxide formed on Si-substrates by BF$_2$ implantation retarded the formation of TaSi$_2$.

• 한국진공학회지
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• 제12권S1호
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• pp.83-87
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• 2003

Zirconium oxide films have been synthesized by radio-frequency magnetron sputtering deposition on n-Si(001) substrate with metal zirconium target at variant $O_2$ partial pressures. The influences of $O_2$ partial pressures of the morphology, deposition rate, microstructure, and the dielectric constant of $ZrO_2$ have been discussed. The results show that deposition rate of $ZrO_2$ films decreases, the roughness, and the thickness of the native $SiO_2$ interlayer increases with the increase of $O_2$ partial pressure. $ZrO_2$ films synthesized at low $O_2$ partial pressure are amorphous and monoclinic polycrystalline in nanometer scale at low $O_2$ partial pressure. The relative dielectrics of $ZrO_2$ films are in the range of 12 to 25.

• E2M - 전기 전자와 첨단 소재
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• 제5권4호
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• pp.385-392
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• 1992

급속열산화방법으로 400-650.deg.C의 온도범위에서 10-600초 동안 n형 InP기판위에 InP자연산화막을 형성하고 산화막의 성장율, 성장기구와 화학적 구성성분 및 전기적 성질등을 조사하였다. InP자연산화막의 두께는 산화시간이 제곱근에 비례하였고 산화온도에 대하여 지수함수적으로 증가하였다. InP자연산화막은 320.deg.C의 온도에서 초기성장이 이루어지고 산소원자들이 InP내부로 확산되는 과정으로 형성되며 산화막 형성에 필요한 활성화에너지는 1.218eV이었다. InP 자연산화마그이 화학적성분은 In$_{2}$)$_{3}$, P$_{2}$O$_{5}$ 및 InPO$_{4}$의 산화물이 혼합하여 구성된다. Au/InP쇼트키다이오드와 InP자연산화막을 게이트절연물로 사용한 MOS 다이오드의 전기적 특성은 다이오드방정식에 따르는 전류-전압특성을 보였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.106-108
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• 1994

Electromigration(EM) tests were carried out on Al and Cu films in HV systems to study surface migration. The Al films were made on oxidized silicon wafers by thermal evaporation, in-situ annealed at 300$^{\circ}C$, patterned, and EM tested at 260$^{\circ}C$ and 4.5MA/$\textrm{cm}^2$. SEM observation with back scattered electron mode on the EM tested Al films disclosed that thinning took place under the native Al oxide. In the case of Cu films, tested using in-situ TEM, thinning was also observed at the early stage of void formation even though the thinned areas were much less than those of the Al films.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.250-253
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• 1990

A single-crystalline epitaxial film of GaAs has been grown on Si using an ionized cluster beam technique. The native oxide layer on the silicon substrate was removed at $550^{\circ}C$ by use of an accelerated arsonic ion beam, instead of a high-temperature desorption. During the growth the substrate temperature was maintained at $550^{\circ}C$. Transmission electron microscopy and electron diffraction data suggest that the eats layer is an epitaxially grown single-crystalline layer.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.77-77
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• 2019

Herbal medicines have been used as a basic means of clinical trial throughout history, and traditional medicines are targeted to seek functional components. To discover new cosmetic or food ingredients among numerous natural resources from Jeju island, we screened for inhibition activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Although NO formation plays an important role to relax vascular muscles or eliminate tumors, NO produced excessively in inflammatory condition can cause metabolic diseases or inflammatory dysfunctions. Among 52 natural resources ethanol extracts, 5 extracts inhibited NO production over 25% compared to only LPS-treated control at the concentration of $100{\mu}g/mL$. In further study, we try to investigate other bio-activities and the phytochemicals of 5 different extracts as useful ingredients for cosmetics or functional foods.