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XPS requires high vacuum (residual gas pressure p ~ 10 −6 Pa) or ultra-high vacuum (p < 10 −7 Pa) conditions, although a current area of development is ambient-pressure XPS, in which samples are analyzed at pressures of a few tens of millibar. When laboratory X-ray sources are used, XPS easily detects all elements except hydrogen and helium.
Three regions of XAS data. Extended X-ray absorption fine structure (EXAFS), along with X-ray absorption near edge structure (), is a subset of X-ray absorption spectroscopy ().
Principle of angle-resolved photoemission spectroscopy. Photoemission spectroscopy ( PES ), also known as photoelectron spectroscopy , [ 1 ] refers to energy measurement of electrons emitted from solids, gases or liquids by the photoelectric effect , in order to determine the binding energies of electrons in the substance.
Image of a Kratos Axis-165 system equipped with XPS, ISS, and AES, from Alberta Centre for Surface Engineering and Science (ACSES). Low-energy ion scattering spectroscopy (LEIS), sometimes referred to simply as ion scattering spectroscopy (ISS), is a surface-sensitive analytical technique used to characterize the chemical and structural makeup of materials.
The U.S. management did not want the laboratory to be converted to a manufacturing unit so it decided to set up a commercial unit to further develop the X-ray instrumentation market. In 1953 Norelco Electronics was established in Mount Vernon, NY, dedicated to the sale and support of X-ray instrumentation.
X-ray photoelectron spectroscopy (XPS) is another close relative of EDS, utilizing ejected electrons in a manner similar to that of AES. Information on the quantity and kinetic energy of ejected electrons is used to determine the binding energy of these now-liberated electrons, which is element-specific and allows chemical characterization of a ...
In principle, the lightest element that can be analysed is beryllium (Z = 4), but due to instrumental limitations and low X-ray yields for the light elements, it is often difficult to quantify elements lighter than sodium (Z = 11), unless background corrections and very comprehensive inter-element corrections are made.
The first XES experiments were published by Lindh and Lundquist in 1924 [7]. Fig. 2: Energy level diagram K-lines. In these early studies, the authors utilized the electron beam of an X-ray tube to excite core electrons and obtain the -line spectra of sulfur and other elements.