Oxidation Behavior of Pd-Si Compounds

1982 ◽  
Vol 18 ◽  
Author(s):  
A. Cros ◽  
R. A. Pollak ◽  
K. N. Tu
Keyword(s):  
Chemical Analysis ◽  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Room Temperature ◽  
Oxidation Behavior ◽  
Spillover Effect ◽  
Photoemission Spectroscopy ◽  
Temperature Oxidation ◽  
X Ray ◽  
Oxygen Dissociation

The room temperature oxidation of PdSi, Pd2Si and Pd4Si has been studied using X-ray photoelectron spectroscopy (X-ray photoemission spectroscopy or electron spectroscopy for chemical analysis). We find that only silicon atoms in these silicides are oxidized and the oxidation of Pd4Si surfaces is enhanced compared with that of Pd2Si and PdSi, as is evidenced by both a higher silicon oxidation state and thicker oxide films. This behavior is discussed in terms of silicide stability and a spillover effect where palladium atoms catalyze molecular oxygen dissociation.

The Oxidation Behavior of the √3×√3 Ag and Au/Si(111) Surfaces at Room Temperature Studied by Photoemission

1985 ◽  
Vol 54 ◽  
Author(s):  
J. J. Yeh ◽  
D. J. Friedman ◽  
R. Cao ◽  
J. Hwang ◽  
J. Nogami ◽  
...  
Keyword(s):  
Valence Band ◽  
Room Temperature ◽  
Oxidation Behavior ◽  
Photoemission Spectroscopy ◽  
Oxide Formation ◽  
Temperature Oxidation ◽  
X Ray ◽  
Initial Stage ◽  
Energy Distribution Curve ◽  
Valence Band Electron

ABSTRACTThe differences of the room temperature oxidation behavior of ordered Ag/Si(111) and Au/Si(111) surfaces were studied by surface sensitive soft x-ray photoemission spectroscopy obtained with synchrotron radiation. Si surfaces covered with a monolayer of Ag or Au, once annealed to display a √3×√3 LEED pattern, were believed to be passivated against oxidation according to earlier reports. This work shows that these two surfaces oxidize but in a different way. Up to 104 L O2 exposures, the observed valence band of the Au/Si surface's valence band electron energy distribution curve is almost identical to that of the surface before oxygen exposure. But the corresponding Si 2p core level spectrum shows a small chemically shifted component indicating an initial stage of the formation of Si oxide. Thi3 chemically shifted signal becomes a strong peak at -3.7 eV below the clean Si position, characteristic of SiO2, after subsequent O2 exposures up to 1010 L. The Ag/Si system behaves in a similar fashion, but oxide growth saturates at 108 L, and the final oxides formed include a distribution of suboxides in addition to SiO2. Clearly, oxide formation is not prohibited by the presence of the ordered Au or Ag metal overlayer but delayed. Although the onset of oxidation is delayed compared to that for the clean Si surface, due to the metal-silicon bonding, the oxide formation is much faster once the surface starts to oxidize.

Uniform Depth Profiling in X-ray Photoelectron Spectroscopy (Electron Spectroscopy for Chemical Analysis)

1978 ◽  
Vol 32 (2) ◽  
pp. 175-177 ◽  
Author(s):  
L. Bradley ◽  
Y. M. Bosworth ◽  
D. Briggs ◽  
V. A. Gibson ◽  
R. J. Oldman ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Auger Electron Spectroscopy ◽  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Depth Profiling ◽  
Ion Source ◽  
X Ray ◽  
Nitride Oxide ◽  
Silicon Device

The difficulties of nonuniform ion etching which hamper depth profiling by X-ray photoelectron spectroscopy (XPS) have been overcome by use of a mechanically scanned saddle-field ion source. The system and its calibration for uniformity are described, and its performance is illustrated by the depth profile of a Si3N4/SiO2/Si metal nitride oxide silicon device. This also allows the potential advantages of XPS profiling over Auger electron spectroscopy profiling to be discussed.

High Temperature Oxidation Behavior of SUS310S Austenitic Stainless Steel

2014 ◽  
Vol 941-944 ◽  
pp. 212-215
Author(s):  
Tao Zheng ◽  
Jing Tao Han
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxidation Behavior ◽  
Layer Structure ◽  
Energy Dispersive Spectrometer ◽  
Austenitic Stainless Steels ◽  
Temperature Oxidation ◽  
X Ray ◽  
High Temperature Oxidation Behavior ◽  
High Oxidation Resistance ◽  
Ray Diffusion

The oxidation behavior of SUS310S austenitic stainless steels was studied in isothermal conditions at different temperatures between 800oC and 1100oC for 96h in air. The oxidation kinetics was analyzed, the surface and cross-section of the oxide scale grown by oxidation were characterized by using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffusion (XRD) and X-ray photoelectron spectroscopy (XPS). The SUS310S steel has high oxidation resistance at 800oC and with the increase of the temperature, the parabolic rate constants is constantly increasing. Examination of the morphology and composition of oxide layers reveals a double-layer structure, The inner layer is mainly chromium oxide (Cr2O3) and is covered by an uneven thinness outer layer of manganese-chromium or iron-chromium spinel oxide.

Adhesive Bonding of Various Materials to Hard Tooth Tissues. XIV. Enamel Mordant Selection Assisted by ESCA (XPS)

1978 ◽  
Vol 57 (4) ◽  
pp. 551-556 ◽  
Author(s):  
R.L. Bowen
Keyword(s):  
Chemical Analysis ◽  
Phosphoric Acid ◽  
Surface Analysis ◽  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Adhesive Bonding ◽  
Acid Etching ◽  
Etching Solution ◽  
X Ray

Surface analysis by XPS (X-ray photoelectron spectroscopy), also called ESCA (electron spectroscopy for chemical analysis), indicates that only certain cations are appreciably sorbed by enamel from an acid etching solution containing phosphoric acid and equimolar concentrations of candidate mordant salts.

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