Time-of-flight secondary ion mass spectrometry of industrial materials Original Research Article

Surface phenomena are important in numerous technological areas, such as adhesion, friction, biocompatibility, catalysis, polymer science or composite research. Most of the critical parameters affecting the stability and specific response of industrial products to the environment are controlled by the chemical composition of the uppermost monolayers of a material. Since many of the technological important systems are of organic nature, the demand for detailed molecular information has become vital for specific modification of surfaces with respect to their desired properties. Time-of-flight secondary ion mass spectrometry is developing into one of the most significant and versatile analytical techniques for characterizing the surface chemistry of inorganic, organic and biological materials. Secondary ions are generated as a consequence of the impact of a pulsed primary ion beam (Cs+, Ga+) onto the surface. The high transmission and excellent mass resolution (M/ΔM=7500 at mass m/e=28) of time-of-flight analyzers are responsible for the possibility of detecting very low concentrations of chemical species under static conditions (primary ion flux density ≤1013 ions cm2), i.e. with minimal removal of material from the surface. Imaging the lateral distribution of chemical species with a useful resolution of ca. 1 μm can be achieved by rastering the primary ion beam over a selected area of the substrate.