Study on quantitative behavior of barium (II) Stearate by static-SIMS

Multi-built-up layers of barium (II) stearate on a copper substrate were investigated by a static SIMS apparatus equipped with a quadrupole mass spectrometer, and the experimental approach for quantitative SIMS analysis was discussed. Organic layers were built up by Langmuir-Blodgett method and impacted by 430 eV, 20 μA/cm2 Ar+ ions. Ba+, C sub(n)H sub(m)sup(+) ions from barium (II) stearate and Cu+ ions from the substrate were detected. A variation of peak intensities of CnHm+ showed a complicate change as a function of bombardment time, while Ba+ and Cu+ peak intensities were exponentially decreased. It might be assumed that unexpected strong Cu+ ions sputtered off through multi-built-up layers are attributed to the bulky structure of the layers. A linear relationship was obtained between barium surface concentration and the maximum values of I sub(Ba)sup(+)/(I sub(Ba)sup(+) + I sub(Cu)sup(+)). (author)