Characterization of surface structure by cluster coincidental ion mass spectrometry

Coincidental ion mass spectrometry, CIMS, is a technique in which spatial and/or chemical relationships are investigated by collection and analysis of coincidental ion emission events. Practical application of CIMS is dependant upon two factors. One is that the primary ion be selected so as to maximize coincidental ion, CI, yields. Polyatomic projectiles are best suited for this type of analysis because, in certain cases, they not only enhance conventional secondary ion yields but CI yields as well compared to that of equal velocity atomic projectiles. The second factor is that data collection and analysis be as efficient as possible. Experiments were run in an event-by-event bombardment/detection mode. All secondary ions from each impact were recorded with subsequent offline analysis of coincidental ion emission. We report here the combination of cluster SIMS (22 keV Au3þ projectiles) with a fresh approach to data analysis for evaluation of a-zirconium phosphate in both gel and crystalline states. Results presented here show that it is possible to distinguish between these two phases although the stoichiometry of the compound is the same. # 2004 Elsevier B.V. All rights reserved