High sensitivity FIB-SIMS analysis of semiconductor devices

High energy gallium ion beams used in focused ion beam (FIB) instruments produce secondary ion fluxes from silicon that are comparable with sputtering by inert gas primary ion beams. Use of reactive primary ions such as oxygen and caesium lead to a large increase in the ionisation yield. This paper reports a systematic study of the ionisation yield enhancement by pre-treating the surface with implanted oxygen ions prior to compositional imaging by FIB-SIMS microscopy for common dopant and impurity elements. Yield enhancements of nearly three orders of magnitude are reported.