Instrumentation Auger electron spectroscopy

Auger electron spectroscopy (AES), 76 495 24 84-87, 94-97. See also AES instrumentation archaeological materials, 5 744 quantitative, 24 98 Auger sensitivity factors, 24 96 Auger spectra, 24 95-97, 98 Auger transitions, 24 95 Augite, in coal, 6 718 Au(III) halides, 72 706. See also Gold(III) entries... 

Turner, N. H. (1997). X-ray photoelectron and Auger electron spectroscopy. In Analytical Instrumentation Handbook, ed. Ewing, G. W., New York, Marcel Dekker, pp. 863-914 (2nd edn.). 

The experiments were performed in stainless steel UHV chambers which were equipped with the instrumentation necessary to perform Auger Electron Spectroscopy (AES), X-ray Photoelectron Spectroscopy (XPS), UV Photoelectron Spectroscopy (UPS), Low Energy Electron Diffraction (LEED), work function measurements (A( )), High Resolution Electron Energy Loss Spectroscopy (HREELS), and Temperature Programmed Desorption (TPD). The Au(lll) crystal was heated resist vely and cooled by direct contact of the crystal mounting block with a liquid nitrogen reservoir. The temperature of the Au(lll) crystal was monitored directly by means of a... 

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 instrumental needs required to perform such methods are similar, xps and aes instrumentation will be discussed together. 

Techniques that fall within the general heading of electron spectroscopy for chemical analysis (ESCA) include photoelectron spectroscopy of inner shell electrons (PESIS), photoelectron spectroscopy of outer shell electron (PESOS), and Auger electron spectroscopy (C2, H16, Pll). The advantages of ESCA are high sensitivity, easily interpreted spectra, and that the sample is not destroyed (H27). A few commercial instruments are now available. 

Recently, new instrumental techniques have become available for determining surface structures on an atomic scale. These include X-ray fine structure (EXAFS), electron spectroscopies, ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), ion spectroscopies, secondary-ion... 

Until recently, analytical investigations of surfaces were handicapped by the lack of suitable methods and instrumentation capable of supplying reliable and relevant information. Electron diffraction is an excellent way to determine the geometric arrangement of the atoms on a surface, but it does not answer the question as to the chemical composition of the upper atomic layer. The use of the electron microprobe (EMP), a powerful instrument for chemical analyses, is unfortunately limited because of its extended information depth. The first real success in the analysis of a surface layer was achieved by Auger electron spectroscopy (AES) [16,17], followed a little later by other techniques such as electron spectroscopy for chemical analysis (ESCA) and secondary-ion mass spectrometry (SIMS), etc. [18-23]. All these techniques use some type of emission (photons, electrons, atoms, molecules, ions) caused by excitation of the surface state. Each of these techniques provides a substantial amount of information. To obtain the optimum Information it is, however, often beneficial to combine several techniques. 

The reducticxi of the process tenperature results in very little reaction between the film and the substrate as shown by the Auger electron spectroscopy (AES) results of figs. 9a and 9b. In fig. 9a the AES results Indicate a reacted layer on the order of 100 ntn in a HTP film of the order of 350 nm. However, in the LTP film shown in fig. 9b the interface reacticxi extends over a region of less than 12 nm, close to the Instrument resolution of the technique. This result is very important for the fabrication of structures containing abn rt junction. 

Benninghoven, A. Rudenauer, F.G. Wemer, H.W. Secondary Ion Mass Spectrometry Basic Concepts, Instrumental Aspects, Applications and Trends, John Wiley and Sons New York, 1987. Briant, C.L. Messmer, R.P., Eds. Auger electron spectroscopy. In Treatise on Materials Science and Technology, Academic Press, Inc. San Diego, CA, 1988 Vol. 30. 

Three types of instrumentation exist for dynamic SIMS non-imaging ion probes, direct-imaging ion microanalysers and scanning ion microprobes-micro-scopes. Non-imaging ion probes are often an accessory of Auger electron spectroscopy (AES), electron spectroscopy for chemical applications (ESCA), or electron microscopy systems and allow a point analysis. Imaging equipment allows a point-to-point analysis of the surface with a primary beam of size 10—300 pm (microanalysers) or below 10 pm (microprobes-microscopes). 

Surface EXAFS (SEXAFS) uses Auger or photo-electrons to detect the EXAFS signal. This ensures that this technique has a much higher surface sensitivity than EXAFS acquired using the total electron yield method. SEXAFS requires ultra-high vacuum and the detection instrumentation normally associated with Auger electron spectroscopy (AES) or X-ray photoelectron spectroscopy (XPS) techniques. 

Chourasia AR and Chopra DR (1997) Auger electron spectroscopy. In Settle F (ed.) Handbook of Instrumental Techniques for Analytical Chemistry, pp. 793-808. NJ Prentice-Hall. 

A number of techniques are available to interrogate material surfaces. The development of instrumentation suitable for this type of examination has occured relatively recently, in the last quarter of a century or so. Some of these methods, however, are simply not suitable for polymer analysis, (for example. Auger electron spectroscopy (AES), where the electron beam used as an excitation source is too energetic to avoid damage to organic materials) and all of them have limitations in terms of the information they can provide. By combining techniques which give complementary information one can obtain a detailed description of a polymeric interface. 

Chourasia, A. R., and D. R. Chopra. Auger Electron Spectroscopy. In Handbook of Instrumental Techniques for Analytical Chemistry, edited by Frank Settle. New York Prentice Hall Professional Reference, 1997. This chapter provides a thorough and systematic description of the principles and practical methods of Auger spectroscopy, including its common applications and limitations. 

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