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چکیده
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During the study of materials, some properties are considered to act dependently on the surface structure. Various techniques such as Low Energy Ion Scattering (LEIS), Secondary Mass Ion Spectroscopy (SIMS), Auger Electron Spectroscopy AES and etc..., are used to study the surfaces of materials. Some of these techniques are more sensitivity to the topmost layers of the surfaces than others and we will discuss in detail. Low Energy Ion Scattering is also called Ion Scattering Spectroscopy and is a tool used for the study of the atomic composition, concentration and structure of a surface, using low energy ions with energy ranging from 100 eV to 10 keV scattered off the surface. This technique is known to be more sensitive to the first layer, the non-destructive in depth analysis of the near surface (0-10nm). In Secondary Mass Ion Spectroscopy involves primary ion beam with a typical energy range between 100 and 25 keV is bombarded incident on a surface and due to the transferred impact energy, neutral atoms, molecule and ions, so-called secondary ion, are emitted from the surface. They are detected and analyzed by a mass spectrometer. The measured mass spectrum then, yields information for the chemical composition of the surface. This technique can be used in surface physics to study the composition of the topmost atomic layers, including the nature and properties of adsorbed layers. One monitors the secondary-ion mass spectra, which yield information about the chemical elements contained in the removed material. Auger Electron Spectroscopy (AES) is a tool used for standard analysis of the surface and interface physics, used predominantly to check the cleanliness of a freshly prepared surface under UHV conditions. The important fields of application (elemental analysis) as well as depth profiling of the concentration of particular chemical elements and other applications involve alternate sputtering and AES stages.
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