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The Storing Matter technique has been developed to perform quantitative surface analysis with high sensitivity. This technique consists in decoupling the sputtering of the specimen from the subsequent analysis step. In the recently developed prototype instrument, the sample surface is sputtered by an ion beam and the emitted particles are deposited at submonolayer level on a dedicated collector under UHV conditions. In a second step, the matter deposited on the collector is analyzed by SIMS in dynamic or static mode. The chemical nature of the collector surface is chosen with regard to the subsequent SIMS analysis (high or low work function to enhance positive or negative ionization, metallic overlayer for optimized organic information by cationization, etc.) by depositing thin films by electron beam evaporation. This paper presents the first results obtained on polymer samples (PMMA, PVC and PS) with the Storing Matter prototype instrument. The chosen collector surface was Ag, which is known to enhance cationization in static SIMS. The positive mass spectra obtained from Storing Matter deposits on Ag collectors were compared to those recorded on polymer reference samples and on the pristine Ag collectors. This study showed that the Storing Matter technique allows for a clear identification of the PMMA and PVC deposits while enhancing the secondary ion intensities in the higher-mass range with respect to a conventional static SIMS analysis of the polymer.

aThe introduction of boron in amounts of tens parts per million (ppm) increases the hardenability of steels. Nevertheless, this positive effect of boron can drastically be reduced during the industrial process if boron precipitation occurs. In order to identify the different steps of boron precipitation for the main parts of the process (deformation at high temperature, cooling and welding), the distribution of boron in high strength steels is studied through SIMS nano-analysis. It is shown that the B state and the nature of the B precipitates can be directly deduced from different ion maps ( 11 B, 12 C, 11 B 12 C, 11 B 14 N, 11 B 16 O) acquired simultaneously. Depending on the progress of the process, borocarbides and boron nitrides precipitates are observed.

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The increase of traffic and the rising energy consumption mean a challenge to the air pollution control and to environmental protection. Measures of air pollution control concentrated primarily on the reduction of gaseous pollutants. However, in the field of air hygiene in Central Europe, especially the load of near-surface atmospheric dust becomes threatening to human health. A SIMS microprobe for ultra fine feature analysis is used to image the elemental composition at the surface of submicrometer urban dust particles collected at two measurement stations in the Grand Duchy of Luxembourg. The NanoSIMS 50 has been chosen because it creates one intensity image for each selected element in a high spatial resolution down to 50 nm. The atmospheric fine dust consists of a mixture of organic and inorganic compounds. The elemental composition at the surface of particles was studied using a global image segmentation technique to separate the signal from the background of the particles. The analysis of the binary intensity images was carried out using several shape and proximity measures. The patch shape complexity and distribution for industrial/urban particles were found to differ significantly from the solids collected from a forest site. We conclude that the methodology developed in the study is a reliable tool to differentiate between potential sources of airborne particulate matter.