Low Energy Ion Scattering Spectroscopy (LEIS/ISS)

A highly surface sensitive spectroscopy which compliments the chemical and quantitative analysis offered by XPS.

Ion Scattering Spectroscopy (also known as ISS or LEIS) is a technique whereby a monoenergetic beam of He+ or Ar+ ions are scattered by the atoms in a surface.

The loss of kinetic energy due to scattering caused by the mass difference between ion and scattering atom is measured and a spectrum is produced.  Clearly two atoms in a surface which have very different masses (for example, oxygen and iron) will scatter ions differently.

More information on ISS can be found at:



  • detection of top-most surface elements
  • determination of the relative surface coverage of a given element.
  • adsorption on single crystal materials
  • indication of monolayer surface coverage (e.g. by a self-assembled monolayer)
  • growth of ultra-thin layers such as those produced by atomic layer deposition (ALD).


Systems at Harwell (all), Cardiff (Ultra) and UCL (Theta Probe) are equipped with ISS.