Escape depth

{
  "id": "MLC-T-CHM-004096",
  "term": "Escape depth",
  "field": "Chemistry",
  "definition": "The distance perpendicular to a solid surface from which an electron or other particle has a specific probability, typically 1/e (about 37%), of escaping into the vacuum without undergoing an inelastic collision. This parameter determines the surface sensitivity of electron spectroscopy techniques like XPS and AES. The escape depth is a function of the electron's kinetic energy and the material being analyzed.",
  "subject": "Analytical Chemistry",
  "references": [
    "PAC, 1979, 51, 2243. 'General aspects of trace analytical methods - IV. Recommendations for nomenclature, standard procedures and reporting of experimental data for surface analysis techniques' on page 2247 (https://doi.org/10.1351/pac197951112243)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/escape-depth/"
}