When a solid sample is sputtered by primary ions of few keV energy, a fraction of the particles emitted from the target is ionized. Secondary Ion Mass Spectrometry consists of analyzing these secondary ions with a mass spectrometer. Secondary ion emission by a solid surface under ion bombardment supplies information about the elemental, isotopic and molecular composition of its uppermost atomic layers. SIMS is the most sensitive elemental and isotopic surface analysis technique.  The secondary ion yields will vary greatly according to the chemical environment and the sputtering conditions (ion, energy, angle). This can add complexity to the quantitative aspect of the technique.

The SIMS technique provides a unique combination of extremely high sensitivity for all elements from Hydrogen to Uranium (detection limit down to ppb level for many elements), high lateral resolution imaging (down to 40 nm), and a very low background that allows high dynamic range (more than 5 decades). This technique is "destructive" by its nature (sputtering of material). It can be applied to any type of material (insulators, semiconductors, metals) that can stay under vacuum. See some examples of application and results obtained with a IMS 7f.

It allows molecular as well as elemental characterization of the first top monolayer in the static SIMS mode. It allows also the investigation of bulk composition or depth distribution of trace elements in the dynamic SIMS mode, with a depth resolution ranging from one to 20-30 nanometers. 

This is why SIMS is one of the most widespread surface analysis techniques for advanced material research.
CAMECA has developed a complet SIMS-product-line, each of these high-end instruments ensures the best performance for a given application.