Auger electronic spectroscopy

AES ARABS Auger electron spectroscopy [77, 112-114, 117] Angle-resolved AES [85, 115] An incident high-energy electron ejects an inner electron from an atom an outer electron (e.g., L) falls into the vacancy and the released energy is given to an ejected Auger electron Surface composition... 

Electronic spectra of surfaces can give information about what species are present and their valence states. X-ray photoelectron spectroscopy (XPS) and its variant, ESC A, are commonly used. Figure VIII-11 shows the application to an A1 surface and Fig. XVIII-6, to the more complicated case of Mo supported on TiOi [37] Fig. XVIII-7 shows the detection of photochemically produced Br atoms on Pt(lll) [38]. Other spectroscopies that bear on the chemical state of adsorbed species include (see Table VIII-1) photoelectron spectroscopy (PES) [39-41], angle resolved PES or ARPES [42], and Auger electron spectroscopy (AES) [43-47]. Spectroscopic detection of adsorbed hydrogen is difficult, and... 

A popular electron-based teclmique is Auger electron spectroscopy (AES), which is described in section Bl.25.2.2. In AES, a 3-5 keV electron beam is used to knock out iimer-shell, or core, electrons from atoms in the near-surface region of the material. Core holes are unstable, and are soon filled by either fluorescence or Auger decay. In the Auger... 

Powell C J, Jablonski A, Tilinin I S, Tanuma S and Penn D R 1999 Surface sensitivity of Auger-electron spectroscopy and x-ray photoelectron spectroscopy J. Eiectron Spec. Reiat. Phenom. 98-9 1... 

Powell C J 1994 Inelastic interactions of electrons with surfaces applications to Auger-electron spectroscopy and x-ray photoelectron spectroscopy Surf. Sc/. 299-300 34... 

Heiland W and Taglauer E 1975 Low energy ion scattering and Auger electron spectroscopy studies of clean nickel surfaces and adsorbed layers Surf. Sc/. 47 234-43... 

AES Auger electron spectroscopy After the ejection of an electron by absorption of a photon, an atom stays behind as an unstable Ion, which relaxes by filling the hole with an electron from a higher shell. The energy released by this transition Is taken up by another electron, the Auger electron, which leaves the sample with an element-specific kinetic energy. Surface composition, depth profiles... 

Figure 8.1 Processes occurring in (a) ultraviolet photoelectron spectroscopy (UPS), (b) X-ray photoelectron spectroscopy (XPS) and (c) Auger electron spectroscopy (AES)...

Figure 8.1(c) illustrates schematically the kind of process occurring in Auger electron spectroscopy (AES). The process occurs in two stages. In the first, a high-energy photon ejects an electron from a core orbital of an atom A ... 

Fig. 4. Scanning electron micrograph of 5-p.m diameter Zn powder. Neck formation from localized melting is caused by high-velocity interparticle coUisions. Similar micrographs and elemental composition maps (by Auger electron spectroscopy) of mixed metal coUisions have also been made.

X-ray Photoelectron Spectroscopy. X-ray photoelectron spectroscopy (xps) and Auger electron spectroscopy (aes) are related techniques (19) that are initiated with the same fundamental event, the stimulated ejection of an electron from a surface. The fundamental aspects of these techniques will be discussed separately, but since the instmmental needs required to perform such methods are similar, xps and aes instmmentation will be discussed together. 

C. L. Wilson, Comprehensive Analytical Chemisty Ultraviolet Photoelectron and Photoion Spectroscopy Auger Electron Spectroscopy Plasma Excitation in SpectrochemicalAnalysis, Vol. 9, Elsevier Science, Inc., New York, 1979. 

AES = auger electron spectroscopy APS = appearance potential spectroscopy CEELS = characteristic electron energy-loss spectroscopy ... 

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