• Title/Summary/Keyword: Auger Electron Spectroscopy

Search Result 294, Processing Time 0.023 seconds

Free-standing graphene intercalated nanosheets on Si(111)

  • Pham, Trung T.;Sporken, Robert
    • Journal of IKEEE
    • /
    • v.21 no.3
    • /
    • pp.297-308
    • /
    • 2017
  • By using electron beam evaporation under appropriate conditions, we obtained graphene intercalated sheets on Si(111) with an average crystallite size less than 11nm. The formation of such nanocrystalline graphene was found as a time-dependent function of carbon deposition at a substrate temperature of $1000^{\circ}C$. The structural and electronic properties as well as the surface morphology of such produced materials have been confirmed by reflection high energy electron diffraction, Auger electron spectroscopy, X-ray photoemission spectroscopy, Raman spectroscopy, scanning electron microscopy, atomic force microscopy and scanning tunneling microscopy.

The interfacial reactions and phase equilibria of Si/Co/GaAs system (열처리 온도에 따른 Si/Co/GaAs 계의 계면반응 및 상평형에 관한 연구)

  • 곽준섭;김화년;백홍구;신동원;박찬경;김창수;노삼규
    • Journal of the Korean Vacuum Society
    • /
    • v.4 no.1
    • /
    • pp.51-59
    • /
    • 1995
  • (001)방향 GaAs 기판과 Si/Co 박막의 계면반응 및 상평형에 관한 연구를 300-$700^{\circ}C$ 열처리 구간에서 행하였다. 반응에 의한 상전이 과정은 glancing angle X-ray diffraction(GXRD), Auger electron spectroscopy(AES) 및 cross-sectional transmission electron microscopy(GXRD), Auger electron spectroscopy(AES) 및 corss-sectional transmission electron microscopy(XTEM)을 이용하여 분석하였다. Si/Co/GaAs계의 계면반응에서 Co는 $380^{\circ}C$에서 GaAs 기판 및 Si와 반응하여 Co2GaAs과 Co2Si상을 형성하였다. $420^{\circ}C$에서 열처리 후, Co층은 모두 소모되었으며 단면구조는 Si/CoSi/CoGa(CoAs)/Co2GaAs/GaAs으로 전이되었다. $460^{\circ}C$까지 온도를 올려 계속적인 반응을 일으키면 CoGa와 CoAs이 분해되면서 CoSi가 성장하였고, $600^{\circ}C$에서는 Co2GaAs마저 분해되고 CoSi상이 성장하여 GaAs와 계면을 형성하였다. CoSi와 GaAs사이의 계면은 $700^{\circ}C$의 고온까지 안정하였으며 이러한 계면반응 결과는 계산에 의하여 구한 Si-Co-Ga-As 4원계 상태도로부터 이해될 수 있었다.

  • PDF

Study of the growth of Au films on Si(100) and Si films on Ge(100) surface

  • Kim, J.H.;Lee, Y.S.;Lee, K.H.;Weiss, A.;Lee, J.H.
    • Journal of Korean Vacuum Science & Technology
    • /
    • v.6 no.3
    • /
    • pp.133-138
    • /
    • 2002
  • The growth of Au films grown on a Si(100)-2x1 surface and Si films on a Ge(100)-2x1 substrate is studied using Positron-annihilation induced Auger Electron Spectroscopy(PAES), Electron induced Auger Electron Spectroscopy(EAES), and Low Energy Electron Diffraction(LEED). Previous work has shown that PAES is almost exclusively sensitive to the top-most atomic layer due to the trapping of positrons in an image potential well just outside the surface before annihilation. This surface specificity is exploited to profile the surface atomic concentrations during the growth of Au on Si(100) and Si on Ge(100) and EAES provides concentrations averaged over the top 3-10 atomic layers simultaneously. The difference in the probe-depth makes us possible to use PAES and EAES in a complementary fashion to estimate the surface and near surface concentration profiles. The results show that (i) the intermixing of Au and Si atoms occurs during the room temperature deposition, (ii) the segregated Ge layer is observed onto the Si layers deposited at 300k. In addition, the prior adsorption of hydrogen prevents the segregation of Ge on top of the deposited Si and that the hydrogen adsorption is useful in growing a thermally stable structure.

  • PDF

Investigation of NH4OH on Zircaloy-4 Surfaces Using Electron Emission Spectroscopy

  • Jung, Hye-Yoon;Kang, Yong-Cheol
    • Bulletin of the Korean Chemical Society
    • /
    • v.28 no.10
    • /
    • pp.1751-1755
    • /
    • 2007
  • The interaction of ammonium hydroxide (NH4OH) with zircaloy-4 (Zry-4) was investigated using X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) methods. In order to study the surface chemistry of NH4OH/Zry-4 system, the binding energies of N1s, O1s and Zr3d electrons were monitored. The N1s peak intensity was remarkably increased by following cycles of Ar+ sputtering of NH4OH dosed Zry-4 surface at room temperature. Because the nitrogen stayed under the subsurface region was diffused out onto the Zry-4 surface after oxygen concentration was decreased. These could be occurred after the surface oxygen was diffused into the bulk or desorbed out from the surface until Ar+ fluence was 6.0 × 1016 Ar+/cm2 then the surface was relatively atomic deficient state. The O1s peak intensity was decreased by stepwise Ar+ sputtering. After many cycles of Ar+ sputtering, the peak intensities of Zr3d peaks did not change much but the shape of the peak clearly did change. This implies that the oxidation state of zirconium was changed during stepwise Ar+ sputtering of NH4OH/Zry-4. The Zr3d peak intensity of zirconium nitride (ZrNx) increased as the intensity of N1s (from zirconium nitride) increased but the Zr3d peak intensity of zirconium oxide (ZrOx) decreased due to the depopulation of the oxygen species on the surface region. We also observed that the peak intensity of Zr4+ was nearly same after Ar+ sputtering processes but the peak intensity of metallic zirconium increased compared to that of before the sputtering process was performed.

ZnO thin film deposition at low temperature using ALD (ALD를 이용한 저온에서의 ZnO 박막 증착)

  • Kim, H.S.
    • Journal of the Korean Vacuum Society
    • /
    • v.16 no.3
    • /
    • pp.205-209
    • /
    • 2007
  • ZnO thin films were deposited on a Si wafer and a soda lime glass using atomic layer deposition(ALD). The substrate temperature were between $130^{\circ}C{\sim}150^{\circ}C$. The deposition rate of the ZnO film was measured to be $2.72{\AA}$ per cycle. The films were analyzed using field emission scanning electron microscopy(FESEM), X-ray diffractometer(XRD), and Auger electron spectroscopy(AES). Impurity-free ZnO thin films were obtained and the crystallinity was found to be dependant upon the substrate temperature.

Thermal Shock Behavior of TiN Coating Surface by a Pulse Laser Ablation Method

  • Noh, Taimin;Choi, Youngkue;Jeon, Min-Seok;Shin, Hyun-Gyoo;Lee, Heesoo
    • Korean Journal of Metals and Materials
    • /
    • v.50 no.7
    • /
    • pp.539-544
    • /
    • 2012
  • Thermal shock behavior of TiN-coated SUS 304 substrate was investigated using a laser ablation method. By short surface ablation with a pulse Nd-YAG laser, considerable surface crack and spalling were observed, whereas there were few oxidation phenomena, such as grain growth of TiN crystallites, nucleation and growth of $TiO_2$ crystallites, which were observed from the coatings quenched from $700^{\circ}C$ in a chamber. The oxygen concentration of the ablated coating surface with the pulse laser also had a lower value than that of the quenched coating surface by Auger electron spectroscopy and electron probe micro analysis. These results were attributed to the fact that the properties of the pulse laser method have a very short heating time and so the diffusion time for oxidation was insufficient. Consequently, it was verified that the laser thermal shock test provides a way to evaluate the influence of the thermal shock load reduced oxidation effect.

Effects of Oxide Layer Formed on TiN Coated Silicon Wafer on the Friction and Wear Characteristics in Sliding (미끄럼운동 시 TiN 코팅에 형성되는 산화막이 마찰 및 마멸 특성에 미치는 영향)

  • 조정우;이영제
    • Tribology and Lubricants
    • /
    • v.18 no.4
    • /
    • pp.260-266
    • /
    • 2002
  • In this study, the effects of oxide layer farmed on the wear tracks of TiN coated silicon wafer on friction and wear characteristics were investigated. Silicon wafer was used for the substrate of coated disk specimens, which were prepared by depositing TiN coating with 1 ${\mu}{\textrm}{m}$ in coating thickness. AISI 52100 steel ball was used fur the counterpart. The tests were performed both in air for forming oxide layer on the wear track and in nitrogen to avoid oxidation. This paper reports characterization of the oxide layer effects on friction and wear characteristics using X-ray diffraction(XRD), Auger electron spectroscopy(AES), scanning electron microscopy (SEM) and multi-mode atomic force microscope(AFM).

미끄럼운동 시 TiN코팅에 형성되는 산화막이 마찰 및 마멸 특성에 미치는 영향

  • Jo, Jeong-U;Im, Jeong-Sun;U, Sang-Gyu;Lee, Yeong-Je
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
    • /
    • 2002.05a
    • /
    • pp.310-316
    • /
    • 2002
  • In this study, the effects of oxide layer formed on the wear tracks of TiN coated silicon wafer on friction and wear characteristics were investigated. Silicon wafer was used for the substrate of coated disk specimens, which were prepared by depositing TiN coating with $1{\mu}m$ in coating thickness. AISI 52100 steel ball was used for the counterpart. The tests were performed both in air for forming oxide layer on the wear track and in nitrogen to avoid oxidation. This paper reports characterization of the oxide layer effects on friction and wear characteristics using X-ray diffraction (XRD). Auger electron spectroscopy (AES), scanning electron microscopy (SEM) and sliding tests.

  • PDF

Fabrication and magnetic properties of Co-Zn ferrite thin films prepared by a sol-gel process (Sol-gel 법에 의한 Co-Zn Ferrite 박막의 제호와 자기 특성에 관한 연구)

  • 김철성;안성용;이승화;양계준;류연국
    • Journal of the Korean Magnetics Society
    • /
    • v.11 no.4
    • /
    • pp.168-172
    • /
    • 2001
  • Co-Zn ferrite thin films grown on thermally oxidized silicon wafers were fabricated by a sol-gel method. Magnetic and structural properties of Co-Zn thin films were investigated by using x-ray diffractometer (XRD), atomic force microscopy (AFM), auger electron spectroscopy (AES) and a vibrating sample magnetometer (VSM). Co-Zn ferrite thin films annealed at 400 $^{\circ}C$ presented have only a single phase spinel structure without any preferred crystallite orientation. Their surface roughness of Co-Zn ferrite thin films was shown as less than 3 nm and the grain size was about 40 nm for annealing temperatures over 600 $^{\circ}C$. A moderate saturation magnetization of Co-Zn ferrite thin films for recording media was obtained in this study and there is no significant difference of their magnetic property with those external fields of parallel and perpendicular to planes of the films. The maximum value of the coercivity was obtained as 1,900 Oe for Co-Zn ferrite thin film annealed at 600 $^{\circ}C$.

  • PDF

Effect of a Laser Ablation on High Voltage Discharge Plasma Area for Carbon Nitride Film Deposition (고전압 방전 플라즈마에 의한 질화탄소 박막 증착 시 플라즈마 영역에 가한 레이저 애블레이션의 효과)

  • 김종일
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.15 no.6
    • /
    • pp.551-557
    • /
    • 2002
  • Carbon nitride films have been deposited on Si(100) substrate by a high voltage discharge plasma combined with laser ablation in a nitrogen atmosphere. The films were grown both with the without the presence of an assisting focused Nd:YAG laser ablation. The laser ablation of the graphite target leads to vapor plume plasma expending into th ambient nitrogen arc discharge area. X-ray photoelectron spectroscopy and Auger electron spectroscopy were used to identify the binding structure and the content of the nitrogen species in the deposited films. The nitrogen content of the films was found to increase drastically with an increase of nitrogen pressure. The surface morphology of the films was studied using a scanning electron microscopy. Data of infrared spectroscopy and x-ray photoelectron spectroscopy indicate the existence of carbon-nitrogen bonds in the films. The x-ray diffraction measurements have also been taken to characterize the crystal properties of the obtained films.