Auger spectrometry

Matsunaga studied adsorption of n-amylamine on cleavage faces and edge sites of the crystals by the use of Auger spectrometry . He confirmed the easy adsorption and slow desorption on crystal edges, and the very slow adsorption and very easy desorption on cleavage faces. This behaviour is discussed later in relation to the effects of contaminants on friction. 

It has often been assumed that any molybdenum disulphide surface wiil begin to oxidise immediately after cleavage, and that small amounts of oxide are probably even present within the crystal lattice, but Buckley was unable to detect any oxide by Auger spectrometry on the surface of a crystal cleaved in air. It is clear therefore that at normal temperatures and in the absence of high concentrations of moisture the extent of oxidation is extremely small. 

Although at first sight Auger spectrometry might be expected to give fruitful information on surfaces, there are unexpected problems. In their summary of... 

Since many surface properties are as sensitive to structure as they are to contaminants, it is essential to include both in surface characterization. The observation of changes in surface structure and composition induced by physical and chemical processes leads to a more complete understanding of the kinetics and mechanism of interactions taking place at the metal/gas interface. Auger spectrometry and low-energy electron diffraction (LEED) are generally used in conjunction to study those properties. 

The composition of the as-deposited alloy films and anodized films was determined by Auger spectrometry (PHI-660 Perkin Elmer) after five seconds of ion milling of the films. The oxide films were also analyzed with scanning and transmission electron microscopy (TEM). The refractive index of the oxide was measured at A, = 633 nm by ellipsometer LEE - 3M. 

Other probes strike the surface with electrons (Auger spectrometry energy dispersive X-ray... 

The RBS technique is used to establish standards for other analytical techniques such as Auger spectrometry and for impurity analysis. It can be used to perform reverse engineering on thin film systems to determine the composition and design of an unknown thin him structure. It can also be used to non-destructively study the diffusion of material at an interface between a him and a substrate as a funchon of hme and temperature. Figure 10.4... 

In other articles in this section, a method of analysis is described called Secondary Ion Mass Spectrometry (SIMS), in which material is sputtered from a surface using an ion beam and the minor components that are ejected as positive or negative ions are analyzed by a mass spectrometer. Over the past few years, methods that post-ion-ize the major neutral components ejected from surfaces under ion-beam or laser bombardment have been introduced because of the improved quantitative aspects obtainable by analyzing the major ejected channel. These techniques include SALI, Sputter-Initiated Resonance Ionization Spectroscopy (SIRIS), and Sputtered Neutral Mass Spectrometry (SNMS) or electron-gas post-ionization. Post-ionization techniques for surface analysis have received widespread interest because of their increased sensitivity, compared to more traditional surface analysis techniques, such as X-Ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES), and their more reliable quantitation, compared to SIMS. 

Laser ionization mass spectrometry or laser microprobing (LIMS) is a microanalyt-ical technique used to rapidly characterize the elemental and, sometimes, molecular composition of materials. It is based on the ability of short high-power laser pulses (-10 ns) to produce ions from solids. The ions formed in these brief pulses are analyzed using a time-of-flight mass spectrometer. The quasi-simultaneous collection of all ion masses allows the survey analysis of unknown materials. The main applications of LIMS are in failure analysis, where chemical differences between a contaminated sample and a control need to be rapidly assessed. The ability to focus the laser beam to a diameter of approximately 1 mm permits the application of this technique to the characterization of small features, for example, in integrated circuits. The LIMS detection limits for many elements are close to 10 at/cm, which makes this technique considerably more sensitive than other survey microan-alytical techniques, such as Auger Electron Spectroscopy (AES) or Electron Probe Microanalysis (EPMA). Additionally, LIMS can be used to analyze insulating sam-... 

Elastic Recoil Detection Analysis Glow discharge mass spectrometry Glow discharge optical emission spectroscopy Ion (excited) Auger electron spectroscopy Ion beam spectrochemical analysis... 

Surface analysis has made enormous contributions to the field of adhesion science. It enabled investigators to probe fundamental aspects of adhesion such as the composition of anodic oxides on metals, the surface composition of polymers that have been pretreated by etching, the nature of reactions occurring at the interface between a primer and a substrate or between a primer and an adhesive, and the orientation of molecules adsorbed onto substrates. Surface analysis has also enabled adhesion scientists to determine the mechanisms responsible for failure of adhesive bonds, especially after exposure to aggressive environments. The objective of this chapter is to review the principals of surface analysis techniques including attenuated total reflection (ATR) and reflection-absorption (RAIR) infrared spectroscopy. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and secondary ion mass spectrometry (SIMS) and to present examples of the application of each technique to important problems in adhesion science. 

ASTM El078, Standard guide for procedures for specimen preparation, mounting, and analysis in auger electron spectroscopy. X-ray photoelectron spectroscopy, and secondary ion mass spectrometry. ASTM, West Conshohocken, PA. 

The control of materials purity and of environmental conditions requires to implement physico-chemical analysis tools like ESC A, RBS, AUGER, SEM, XTM, SIMS or others. The principle of SIMS (Secondary Ion Mass Spectroscopy) is shown in Eig. 31 an ion gun projects common ions (like 0+, Ar+, Cs+, Ga+,. ..) onto the sample to analyze. In the same time a flood gun projects an electron beam on the sample to neutralize the clusters. The sample surface ejects electrons, which are detected with a scintillator, and secondary ions which are detected by mass spectrometry with a magnetic quadrupole. 

Further structural information is available from physical methods of surface analysis such as scanning electron microscopy (SEM), X-ray photoelectron or Auger electron spectroscopy (XPS), or secondary-ion mass spectrometry (SIMS), and transmission or reflectance IR and UV/VIS spectroscopy. The application of both electroanalytical and surface spectroscopic methods has been thoroughly reviewed and appropriate methods are given in most of the references of this chapter. 

Balsenc LR (1980) Sulfur Interaction with Surfaces and Interfaces Studied by Auger Electron Spectrometry. 39 83-114... 

We have undertaken a series of experiments Involving thin film models of such powdered transition metal catalysts (13,14). In this paper we present a brief review of the results we have obtained to date Involving platinum and rhodium deposited on thin films of tltanla, the latter prepared by oxidation of a tltanliua single crystal. These systems are prepared and characterized under well-controlled conditions. We have used thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES) and static secondary Ion mass spectrometry (SSIMS). Our results Illustrate the power of SSIMS In understanding the processes that take place during thermal treatment of these thin films. Thermal desorption spectroscopy Is used to characterize the adsorption and desorption of small molecules, In particular, carbon monoxide. AES confirms the SSIMS results and was used to verify the surface cleanliness of the films as they were prepared. 

In this chapter, we have chosen from the scientific literature accounts of symposia published at intervals during the period 1920 1990. They are personal choices illustrating what we believe reflect significant developments in experimental techniques and concepts during this time. Initially there was a dependence on gas-phase pressure measurements and the construction of adsorption isotherms, followed by the development of mass spectrometry for gas analysis, surface spectroscopies with infrared spectroscopy dominant, but soon to be followed by Auger and photoelectron spectroscopy, field emission, field ionisation and diffraction methods. 

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