 Most energy of the primary ions is dissipated into the near surface region of the solid by a series of binary collisions.This results in ejection (sputtering) of so-called ‘secondary’ particles such as electrons; neutral species, atoms, and molecules; atomic and cluster ions from the surface.In SIMS it is these secondary ions which are detected and analyzed by a mass spectrometer to produce a mass spectrum of a surface for a detailed chemical analysis of the surface or the solid.