The Kratos Axis Ultra system is also equipped with facilities for Ion Scattering Spectroscopy (ISS).

ISS is a technique where a beam of ions (typically He⁺ or Ar⁺) is directed at the surface of interest and are scattered from the atoms in a surface.  As the ions lose kinetic energy, their resultant kinetic energy is measured and a spectrum is produced where peaks are observed at different kinetic energies related to the mass difference between the ion and the atom. Clearly two atoms in a surface that have very different masses (e.g. oxygen and iron) will scatter ions differently.

ISS is extremely surface sensitive, with only the top-most atomic layer being probed.  Disdvantages of ISS are the extreme sensitivity to surface contamination layers and multiple elements may be difficult to resolve in a single spectrum

How can ISS help?	Common applications?
Detection of top most surface elements	Measurements of adsorbed species on single crystal surfaces
Relative coverage determination of given elements	Following layer growth in-situ in areas such as ALD and indication of monolayer coverage of a surface