• Title/Summary/Keyword: Photoelectron spectroscopy

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The Characteristic of $SnO_2$ Thin Films Grown by LP-Thermal MOCVD (LP-Thermal MOCVD 방법을 이용한 $SnO_2$ 박막의 증착 시간에 따른 특성)

  • Jeong, Jin
    • Journal of Integrative Natural Science
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    • v.1 no.1
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    • pp.54-57
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    • 2008
  • This report examines the variation on structural properties of $SnO_2$ thin films. TEM studies shows some of the interfaces to be atomically faceted. Secondary X-ray photoelectron Spectroscopy Analysis(XPS) depth profiles show that films have a uniform composition along the depth.

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The doping effect and electronic structure of alkali metal doped tris (8-hydroxyquinoline) aluminum

  • Kim, Ki-Soo;Lee, Jong-Lam
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1059-1060
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    • 2009
  • We have investigated the pristine alkali metal doping effect which is the Fermi level of alkali metal doped Alq3 shifts toward the LUMO. In-situ measurements of synchrotron radiation photoelectron spectroscopy revealed that the interface dipole or bend bending in previous reports are not the pristine alkali metal doping effect

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Investigation of Molybdenum Oxide Thin Films for CIGS Applications

  • Bin, Jun-Hyeong;Park, Ju-Yeon;Gang, Yong-Cheol
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.388-388
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    • 2010
  • Molybdenum oxide thin films were deposited on p-type Si(100) by an RF magnetron sputtering method. The physical and chemical properties of these films were studied with X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. The thickness of molybdenum oxide thin films was measured by spectroscopic ellipsometer (SE) and the thickness was about 200 nm. As the oxygen gas pressure increased, the thickness was decreased, the phases of the thin films were changed, and the amount of metallic Mo decreased but the contents of $Mo^{6+}$ species increases.

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Electrolyte-Concentration Effects on Interfacial Reactions Between Lithium Negative Electrode and Electrolyte (리튬금속 음극/전해질 계면반응에 미치는 전해질 농도의 영향)

  • Seo, Hee-Young;Jeong, Soon-Ki
    • Proceedings of the KAIS Fall Conference
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    • 2007.11a
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    • pp.353-355
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    • 2007
  • 본 논문에서는 리튬금속을 음극으로 하는 반전지에 여러 농도의 전해질을 사용하여 그에 따른 충/방전 효율과, 음극 표면을 관찰하는 것에 의해 전해질 농도가 음극/전해질 계면반응에 어떠한 영향을 끼치는지 알아보았다. 또한 X-ray Photoelectron Spectroscopy(XPS)를 사용하여 표면에 생성되는 물질의 조성과 구조를 해석하였다.

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A PMO Approach to Orbital Interactions Through Space and Through Bonds

  • Lee, Ik-Choon
    • Bulletin of the Korean Chemical Society
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    • v.3 no.4
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    • pp.140-144
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    • 1982
  • Through-space and through-bonds interactions between two nonbonding orbitals are shown to be first-order and second-order perturbations of nonbonding orbitals by the framework sigma orbitals. Through-space interactions for diamines and triplet diradicals are always destabilizing, but through-bonds interactions are stabilizing owing to their coupling with through-space effect. Anomalies in level ordering and magnitudes of energy splitting can be rationalized with the present approach. Orbtial interactions predicted with the PMO method were found to be consistent with those obtained by STO-3G calculations and photoelectron spectroscopy.

Electrochemical Reactions of $C_{60}$ Films in the Presence of Water : An Electrochemical Quartz Crystal Microbalance Study

  • 서경자;신명순;전일철
    • Bulletin of the Korean Chemical Society
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    • v.17 no.9
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    • pp.781-786
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    • 1996
  • Mass transport behavior of C60 films on electrodes with different thicknesses has been studied by an Electrochemical Quartz Crystal Microbalance (EQCM) during electrochemical reduction-oxidation processes in the presence of water. C60 films were found to be reduced in the presence of water and they remains quite stable. In thin films, the mass on electrode decreased after a complete cycle while X-ray Photoelectron Spectroscopy (XPS) study does not support the existence or formation of C60-epoxides during electrochemical reduction processes in the presence of water or oxygen.

Isotherm for $Ni-O_2$ Adsorption System

  • Kyoung-Hee Ham;Woon-Sun Ahn
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.231-235
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    • 1990
  • The activation energy of dissociative adsorption of oxygen on polycrystalline nickel surface is calculated from adsorption isotherms obtained using X-ray photoelectron spectroscopy. Negative value of this activation energy (-5.9 kJ/mol) indicates that the adsorption takes place through an undissociated precursor state. An adsorption energy for this precursor state is calculated assuming the precursor state as a moleculary physisorbed state ($E_{ad}$ = -7.9 kJ/mol). Finally, an adsorption isotherm equation is derived as a function of the gas exposure, which agrees with the experimental isotherms reasonably good.

The Etching Mechanism of $(Ba, Sr)TiO_3$Thin Films in $Ar/CF_4$ High Density Plasma ($Ar/CF_4$ 고밀도 플라즈마에서 $(Ba, Sr)TiO_3$ 박막의 식각 메카니즘)

  • Kim, Seung-Beom;Kim, Chang-Il
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.49 no.5
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    • pp.265-269
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    • 2000
  • $(Ba, Sr)TiO_3$thin films were etched with a magnetically enhanced inductively coupled plasma (MEICP) at different CF4/Ar gas mixing ratios. Experimental was done by varying the etching parameters such as rf power, dc bias and chamber pressure. The maximum etch rate of the BST films was $1800{AA}/min$ under $CF_4/(CF_4+Ar)$ of 0.1, 600 W/350 V and 5 mTorr. The selectivity of BST to Pt and PR was 0.6, 0.7, respectively. X-ray photoelectron spectroscopy (XPS) results show that surface reaction between Ba, Sr, Ti and C, F radicals occurs during the (Ba, Sr)TiO3 etching. To analyze the composition of surface residue after the etching, films etched with different CF_4/Ar$ gas mixing ratio were investigated using XPS and secondary ion mass spectroscopy (SIMS).

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A Study on ElectricalㆍOptical Properties of Organic Light Emitting Diode by Oxygen Plasma Surface Treatment of Indium-Tin-Oxide Substrates (ITO 기판의 산소 플라즈마 표면 처리에 의한 OLED의 전기적ㆍ광학적 특성에 관한 연구)

  • Yang Ki-Sung;Kim Byoung-Sang;Kim Doo-Seok;Shin Hoon-Kyu;Kwon Young-Soo
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.54 no.1
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    • pp.8-12
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    • 2005
  • Indium tin oxide(ITO) surface treated by Oxygen plasma has been in situ analyzed using XPS(X-ray Photoelectron Spectroscopy) and EDS(Energy Dispersive Spectroscopy), to investigate the relations between the properties of the ITO surface and the properties of OLED(Organic Light Emitting Diode). We measured electrical resistivity using Four-Point-Probe and calculated sheet resistance, and ITO surface roughness was measured by AFM(Atomic Force Microscope). We fabricated OLED using substrate that was treated optimum ITO surface. The plasma treatment of the ITO surface lowered the operating voltage of the OLED. We have obtained an improvement of luminance and decrease of turn-on voltage.