Measurement method of electron emission spectroscopy that utilizes Auger electrons emitted from the target following excitation with an electron beam or X-ray beam.
Notes: - Chemical species are identified from the energies of the emitted Auger electrons and the typically low energies of the emitted electrons and resulting escape depth mean the technique is particularly sensitive for surface species analysis.
- Most AES is performed under high vacuum or ultra-high vacuum.
- An electron beam in the energy range \(\pu{2 keV}\) to \(\pu{30 keV}\) is often used for excitation of the Auger electrons. Auger electrons can also be excited with X-rays, ions, and other sources, but the term Auger electron spectroscopy, without additional qualifiers, is usually reserved for electron-beam-induced excitation. Where an X-ray source is used, the Auger electron energies are referenced to the Fermi level, but, where an electron beam is used, the reference may either be the Fermi level or the vacuum level. Conventionally, spectra may be presented in the direct or differential forms.
Source:
PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1782 (https://doi.org/10.1515/pac-2019-0404)