• 한국세라믹학회지
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• 제27권1호
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• pp.136-146
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• 1990

Whiskers of SiC were grown from the mixture of silica and graphite powders by Acheson method(direct heating method). The structrua, morphological and chemical characterizations have been performed by X-ray diffractometer(XRD), transmission electron microscopy(TEM), optical microscopy(OM), scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS) and energy dispersive spectrometer(EDS). The growth mechanism of SiC whiskers is also discussed.

• 한국전기전자재료학회논문지
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• 제13권7호
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• pp.563-567
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• 2000

We presented the etch results of indium-tin oxide thin films by using SF$_{6}$/O$_2$gas electron cyclotron resonance plasma and conducted X-ray phtoelectron spectroscopy and quadrupole mass spectrometer analyses for the etch characteristics. The etch rate of the films was greatly dependent on that of oxygen which was the major constituent element of the films. The oxygen was removed by the forms like $O_2$or SOF$_2$. We examined the ratio of atomic content of O and In and the change of this ratio was related to the removal rate of InF$_{x}$ and the S-metal bonding.ing.

• 한국재료학회지
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• 제15권3호
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• pp.209-215
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• 2005

Titanium dioxide films $(TiO_2)$ doped cobalt transition metal were prepared on titanium metal by water spray pyrolysis technique. Micro-morphology, crystalline structure, chemical composition and binding state of sample groups were evaluated using field emission scanning microscope(FE-SEM), X-ray diffractometer(XRD), Raman spectrometer, X-ray photoelectron spectrometer(XPS). $TiO_2$ films of rutile structure were predominately formed on all sample groups and $Ti_2O_3$ oxide was coexisted on the surface of cobalt doped-sample groups. The optical absorption peaks measured by using UV-VIS-NIR spectrophotometer were observed at specific wavelength region in sample groups doped cobalt ion. This result could be analyzed by introducing crystal field theory.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.178.1-178.1
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• 2014

본 연구에서는 RF스퍼터링법에 의하여 유리기판에 NiO를 40 nm만큼 증착시킨후, 30분 동안 각각 상온, $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$, $400^{\circ}C$로 후 열처리 하였다. 박막의 전자적, 광학적 특성은 XPS (X-ray Photoelectron Spectroscopy), REELS (Reflection Electron Energy Loss Spectroscopy)와 UV-Spectrometer를 이용하여 =측정하였고, Hall Effect를 이용하여 전기적 특성을 측정하였다. XPS측정결과, $400^{\circ}C$ 후 열처리 한 NiO박막은 NiO 결합인 Ni2+가 줄어 들면서 금속 결합인 Ni0가 증가하면, 상온에서 띠틈이 4.0eV, 3.4eV로 줄어드는 것을 REELS로 확인 했다. 이 값은 UV-Spectrometer를 이용한 광학적 띠틈과 같음을 보였다. Hall Effect측정 결과 $400^{\circ}C$ 후 열처리한 샘플에서 P-type에서 N-type으로 바뀜을 보였으며, 비저항이 낮아지는 경향을 보였다. UV-Spectrometer를 이용한 광학적 특성을 측정해본 결과, 가시광선영역인 380 nm~780 nm에서의 투과율이 75%이상으로 투명전자소자로의 응용이 가능하다는 것을 보여 주었다.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3145-3150
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• 2010

Ruthenium catalysts modified by selenium have been introduced as alternative materials to Pt in Direct methanol fuel cells (DMFCs). RuSe nano-particles were synthesized on the Vulcan XC72R carbon supports via polyol method. The prepared catalysts were electrochemically and physically characterized by cyclic voltammetry (CV,) linear sweep voltammetry, methanol tolerance test, X-ray diffraction (XRD), Transmission electron microscopy (TEM), Energydispersive Spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). Increasing the Se concentration up to 20 at % increased the electro-catalytic activity for the oxygen reduction. By increasing Se amount, Ru metallic form on the surface was increased. The $Ru_{80}Se_{20}$/C catalysts showed the highest oxygen reduction reaction (ORR) activity and outstanding methanol tolerant property in half cell tests as well as single cell test.

• Corrosion Science and Technology
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• 제12권5호
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• pp.215-219
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• 2013

Aluminum alloy(3003) can be dissolved during hydration process with hot tap water. In order to increase the stability of aluminum alloy, it was pretreated with anodization and phosphoric acid before hydration process. The effect of pretreatment on the surface property changes was analyzed with X-ray Photoelectron Spectroscopy (XPS) and Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES) and their results supported that the increase of hydroxyl group (-OH) on the surface formed during anodization and phosphorous acid treatment prevented the dissolution of aluminum alloy during hydration process at high temperature.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1199-1202
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• 2005

Inside of working PDP, there exist highly reactive conditions in the gap between two glass panels. MgO film and phosphor have been investigated as a function of discharge, also phosphor and sealing frits have been investigated as a function of temperature. Changes of impurity generation of MgO, phosphor and sealing fits were measured by using x-ray photoelectron spectroscopy (XPS) and quadropole mass spectroscopy (XPS) and quadropole mass spectrometer (QMS). Impurities such as CO, $CO_2$, OH and $H_2O$ were increased during discharge and heating treatment. Gaseous impurities such as carbon compounds and water deteriorated the characteristics of PDP operation during of lifetime. So metal is used to remove the impurities of phosphor and sealing frits during hearting, the result that the quantity of the impurities such as carbon monoxide and water was reduced.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.209-212
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• 2001

Polyimide(PI) films have been considered as the interlayer dielectric materials due to low dielectric constant, low water absorption, high gap-fill and planarization capability. The PI film was etched with using inductively coupled plasma (ICP). The etching characteristics such as etch rate and selectivity were evaluated to gas mixing ratio. High etch rate was 8300$\AA$/min and vertical profile was approximately acquired 90$^{\circ}$ at CF$_4$/(CF$_4$+O$_2$) of 0.2. The selectivies of polyimide to PR and SiO$_2$ were 1.2, 5.9, respectively. The etching profiles of PI films with an aluminum pattern were measured by a scanning electron microscope (SEM). The chemical states on the PI film surface were investigated by x-ray photoelectron spectroscopy (XPS). Radical densities of oxygen and fluorine in different gas mixing ratio of 07CF4 were investigated by optical emission spectrometer (OES).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 반도체재료
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• pp.84-87
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• 2001

In this study, $CeO_2$ thin films were etched with a $CF_4/Ar$ gas combination in inductively coupled plasma (ICP), The maximum etch rate of $CeO_2$ thin films is $270{\AA}/min$under $CF_4/(CF_4+Ar)$ of 0.2, 600 W/-200 V, 15 mTorr, and $25^{\circ}C$. The selectivities of $CeO_2$ to PR and SBT are 0.21, 0.25. respectively. The surface reaction of the etched $CeO_2$ thin films was investigated with x-ray photoelectron spectroscopy (XPS). There is a chemical reaction between Ce and F, Compounds such as $Ce-F_x$ are remains on the surface of $CeO_2$ thin films. Those products can be removed by Ar ion bombardment effect, The results of secondary ion mass spectrometer (SIMS) were equal to these of XPS. Scanning electron microscopy (SEM) was used to examine etched profiles of $Ce-F_x$ thin films. The etch profile of over-etched $CeO_2$ films with the $0.5 {\mu}m$ line was approximately $65^{\circ}$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.218.2-218.2
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• 2014

그래핀은 높은 전기 전도도와 열전도도, 기계적 강도를 가지고 있고 동시에 높은 전자이동도($200,000cm^2{\cdot}V{\cdot}^1{\cdot}s{\cdot}^1$) 특성을 갖는 물질로써 차세대 소재로 각광받고 있다. 하지만 그래핀을 소자에 응용하기 위해서는 전사공정과 lithography 공정 과정에서 발생되는 PMMA(Poly methyl methacrylate) residue를 완벽하게 제거해야 하는 문제점이 있다. 특히, lithography 공정 중 완벽하게 PMMA residue 가 제거되지 않고 잔류해 있을 경우에 소자의 life time, performance에 악영향을 준다는 보고가 있다. 이와같은 문제를 해결하기 위해 화학적 cleaning, 열처리를 통한 cleaning, 전류 인가에 의한 cleaning과 같은 방법들을 이용하여 그래핀의 PMMA residue를 제거하는 공정들이 보고되고 있지만, 화학적 cleaning 방법의 경우 chloroform 이라는 독성물질 사용으로 인해 산업적으로 응용이 어렵고, 열처리 방법은 전극 등의 금속이 $200^{\circ}C$ 이상의 높은 온도에서 장시간 노출될 경우 쉽게 손상을 입으며, 전류 인가에 의한 cleaning 방법은 국부적으로만 효과를 볼 수 있기 때문에 lithography 공정 후 PMMA residue를 효과적으로 제거하기에는 한계를 보이고 있다. 본 연구에서는 Ar을 이용하는 Ion beam 시스템을 통해 beam energy를 제어함으로써 PMMA residue를 효과적으로 제거하는 연구를 진행하였다. 최적화된 플라즈마 발생 조건을 찾기 위해 QMS(Quadrupole Mass Spectrometer)를 이용하여 입사하는 ion energy와 flux 양을 컨트롤 하였고, 250 W에서 최적화된 ion energy distribution 영역이 존재한다는 것을 확인할 수 있었다. 또한, 25 Gauss 정도의 electro-magnetic field를 이용하여 Ar의 ion energy를 10 eV 이하로 낮추어 damage를 최소화함으로써 효과적으로 그래핀을 cleaning 할 수 있었다. Cleaning과정에서 ion bombardment에 의해 발생한 damage는 $250^{\circ}C$에서 6시간 동안 annealing 공정을 거치면서 회복되는 것을 Raman spectroscopy의 D peak ($1335cm{\cdot}^1$) / G peak ($1572cm{\cdot}^1$) ratio 로 확인할 수 있었고, PMMA residue의 cleaning 여부는 G peak ($1580cm{\cdot}^1$)의 blue shift와 2D peak ($2670cm{\cdot}^1$)의 red shift를 통해 확인하였다. 그리고 AFM (Atomic Force Microscopy)을 이용하여 cleaning 공정과정에서 RMS roughness가 4.99 nm에서 2.01 nm로 감소하는 것을 관찰하였다. 마지막으로, PMMA residue의 cleaning 정도를 정량적으로 분석하기 위해 XPS (X-ray Photoelectron Spectroscopy)를 이용하여 sp2 C-C bonding이 74.96%에서 87.66%로 증가함을 확인을 할 수 있었다.