• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1341-1345
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• 2007

The surface chemistry of D2O dosed Zircaloy-4 (Zry-4) surface followed by Ar-ion bombardment and annealing was studied by means of X-ray photoelectron spectroscopy (XPS) and Ultraviolet photoelectron spectroscopy (UPS). In the XPS study, Ar-ion bombardment caused decrease of the oxygen on the surface region of Zry-4 and therefore led to change the oxidation states of the zirconium from oxide to metallic form. In addition, oxidation states of zirconium were changed to lower oxidation states of zirconium due to depopulation of oxygen on the surface region by annealing. Up to about 787 K, the bulk oxygen diffused out to the subsurface region and after this temperature, the oxygen on the surface of Zry-4 was depopulated. UPS study showed that the valence band spectrum of the D2O exposed Zry-4 exhibited a dominant peak at around 13 eV and no clear Fermi edge was detected. After stepwise Ar+ sputtering processes, the decrease of the oxygen on the surface of Zry-4 led to suppress the dominant peak around 13 eV, the peak around 9 eV and develop a new peak of the metallic Zr 4d state (20.5-21.0 eV) at the Fermi level.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.266-266
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• 2013

We show a set-up of poly (4,4'-aminotriphenylene hexafluoroisopropylidenediphthalimide) (6F-TPA PI)/Al sample in which holes are injected by photoelectron emission process instead of direct charge carrier injection via metal electrode. In this process, an irreversible electrical phase transition of 6F-TPA PI is found in contrast to the Al/6F-TPA PI/Al structure, leading to a write-once-readmany behavior. The photoelectron spectroscopy results measured before and after the switching process revealed that the irreversible electrical phase transition of 6F-TPA PI is attributed to the chemical modification of the carbonyl group in phthalimide moiety.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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• pp.281-283
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• 2005

Processing Plasmas are very sensitive to a variation in process parameters, To maintain process quality and device field, plasma malfunction should be tightly monitored with high sensitivity. A new monitoring method is presented and this was accomplished by applying discrete wavelet transformation to X-ray photoelectron spectroscopy. XPS data were collected during a plasma etching of silicon carbide. Various effects of DWT factor on fault sensitivity were optimized experimentally. Compared to raw data, total percent sensitivity for DWT data demonstrated a significantly improved sensitivity to plasma faults induced by bias power.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.83-83
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• 2012

본 강연에서는 방사광 연X-선 분광현미경학(spectro-microscopy) 중에서, 표면에서 방출되는 광전자를 이용하는 SPEM (Scanning Photoelectron Microscopy)과 PEEM (Photoemission Electron Microscopy)을 소개하고자 한다. SPEM은 입사하는 X-선을 작은 크기로 집속하여 특정의 작은 공간에서 광전자분광학(XPS) 데이터를 얻거나 특정 광전자에너지의 공간분포를 얻게 해주며, PEEM은 입사한 X-선에 의해 발생한 광전자를 전자렌즈 원리로 영상을 맺히게 하여 광전자의 발생 분포를 구하게 한다. 이들은 균일하지 아니한 이종의 표면 연구에 매우 유용한 측정기법들이지만, 그 원리 및 구성은 많은 차이점들을 가지고 있다. 예를 들어, SPEM은 시료를 scanning하면서 XPS에 보다 충실한 타입이고 PEEM은 full field imaging 타입으로 표면변화의 동역학 연구에 강점이 있다. 본 강의에서는 이들 각각의 원리, 장점들에 대해서 설명하고, 활용 예를 제시하고자 한다. 활용 분야에 있어서, SPEM의 경우는 포항가속기연구소의 SPEM으로 수행되었던 DMS, graphene, nano-lithography, OLED, 등 반도체 및 나노 소재, 소자에의 활용에 대한 예를 제시할 것이다. PEEM의 경우는 포항가속기연구소의 응용 예와 박막 형태의 magnetic material에 대한 예들을 제시할 것이다.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1441-1444
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• 2013

Hetero-dimer anions of naphthalene (Np), anthracene (An), phenanthrene (Ph) and pyrene (Py) were investigated using the time-of-flight mass spectrometer (TOF-MS), anion photoelectron spectroscopy (PES) and theoretical calculation. There are two possible geometries with their electron affinity (EA) difference: parallel displaced (PD) and T-shaped. Dispersion force plays a key role in PD structure with the formation of a new anionic core while ${\pi}$-hydrogen interaction plays a key role in T-shaped structure with the monomer anionic core. The optimized structures and charge distributions can simply be explained by the relative difference of EA.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.140.1-140.1
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• 2013

The native silicon-oxide (SiOx) layer at the metal/Silicon interface acts as an electrical resistance to the metal contact of devices. Various methods are proposed for removing this layer, such as sputtering before metal contact formation or high temperature annealing. We studied the chemical evolution of the Au/SiOx/Si system during the annealing at $500^{\circ}C$ using a spatially resolved photoelectron emission method. Scanning photoelectron emission microscopy (SPEM) and core level spectra from local area of the sample show the inhomogeneous oxidation and formation of silicide of Au, as well as valence band spectra reveals the role of Au atoms during the dissociation process of SiOx.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.348-348
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• 2011

We present the interfacial electronic structures of electrodeposited Cu and Fe on bare and 1,4-phenylene diisocyanide (PDI)-functionalized Au nanoisland templates (NITs), and Au and Ag nanoparticles on transition metal oxide supports. Our discussion is based on the depth-profiling X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM).

• 분석과학
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• 제7권1호
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• pp.115-124
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• 1994

탈지과정을 거친 냉연 강판을 순수로 세정하는 과정에서 발생하는 rust와 이러한 rust 발생을 방지하기 위하여 0.05%(wt) $Na_5P_3O_{10}$ 용액으로 표면처리한 냉연 강판의 표면은 X-ray Photoelectron Spectroscopy(XPS) 방법으로 비교 분석하였다. Rust가 발생한 냉연 강판의 표면은 $Fe_2O_3$ 및 FeO, 그리고 $Fe(OH)_3$등으로 구성되는 산화층이 $1500{\AA}$정도의 두께로 존재함을 알 수 있었고, 한편 $Na_5P_3O_{10}$ 용액으로 표면처리한 냉연 강판의 표면은 $60{\AA}$정도의 인산염 피막이 얇은 Fe 산화층 위에 존재함으로써 보호 피막의 역할을 한다는 것을 알 수 있었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.168-171
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• 2017

X-ray photoelectron spectroscopy(XPS) 분석법을 이용하여 FKM O-ring의 대기중에서의 노화 메카니즘을 관찰하였다. FKM O-ring은 선경 3.53mm, 내경 91.67mm인 오링을 시편으로 사용하였다. 노화 후 FKM O-ring의 oxygen 원소의 농도가 20.39%로 증가하였으며, fluorine 원소는 각각 8.29%로 감소하는 경향을 나타내었다. 이를 통하여 산소에 의한 산화 반응이 FKM O-ring의 주요 노화 반응으로 나타났다. C1s와 F1s 피크 분석 결과, FKM O-ring의 주쇄중 C-F 결합에서 산화 반응이 주로 진행되는 것으로 나타났다. 또한 O1s 피크 분석 결과, 산화 반응을 통하여 C-OH, C=O, 그리고 O=C-O 구조를 형성하며, 주로 카르복실기가 생성되는 것으로 나타났다.

• Journal of Korean Vacuum Science & Technology
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• 제4권1호
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• pp.1-5
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• 2000

The C 1s photoelectron energy loss spectra of tris (8-hydroxy-quinoline) aluminum (Alq$_3$) and N,N'-diphenyl-N,N'-bis (3-methyl phenyl)-1,1'-bi-phenyl-4,4'-diamine (TPD) thin films have been investigated. Two major loss structures, namely the plasmon dominated loss lines and shake-up satellites, have been observed. The shake-up spectrum of the C 1s photoelectron line is directly related to the $\pi$-$\pi$$\^$*/ energy gap of the molecule which plays an important role in organic electroluminescent materials. The molecular orbitals of Alq$_3$ and TPD and their major components, quinolime and benzene, have been calculated with the AMI semi-empirical method. The amount of the plasma-dominated loss of Alq$_3$ and TPD, which has to do with the delocalization of electrons through the molecule, was about 24 eV, alike in both cases. The main peak of the C 1s shake-up spectrum of Alq$_3$ and TPD, however, was 5.2 eV and 6.8 eV respectively. It was found that the main shake-up peak reflects more the local $\pi$\longrightarrow$\pi$$\^$*/ transition of quinoline and benzene component rather than the excitation of the whole molecule of Alq$_3$ and TPD. The C 1s shake-up spectra, however, revealed some correlation with the optical energy gap of the organic eletroluminescent materials.