Surface information, primary

SIMS is a very surface-sensitive technique because the emitted particles originate from the uppermost one or two monolayers. The dimensions of the collision cascade are rather small and the particles are emitted within an area of a few nanometers diameter. Hence, SIMS can be used for microanalysis with very high lateral resolution (50 nm to 1 pm), provided such finely focused primary ion beams can be formed. Furthermore, SIMS is destructive in nature because particles are removed from the surface. This can be used to erode the solid in a controlled manner to obtain information on the in-depth distribution of elements.109 This dynamic SIMS mode is widely applied to analyze thin films, layer structures, and dopant profiles. To receive chemical information on the original undamaged surface, the primary ion dose density must be kept low enough (<1013 cm-2) to prevent a surface area from being hit more than once. This so-called static SIMS mode is used widely for the characterization of molecular surfaces (see Figure 3.10). 

Primary surface information surface area, adsorption site concentration. 

Primary surface information electronic structure, surface structure. 

Primary surface information valence band structure, bonding. 

Primary surface information chemical environment, oxidation state. 

Primary surface information composition, oxidation state. 

Primary surface information bonding geometry, molecular orientation. 

Primary surface information local surface structure and coordination numbers. 

Primary surface information surface structure and surface diffusion. 

Similar to ARPEFS, but with a somewhat lower energy range. Primary surface information surface structure. 

Primary surface information forces acting on molecules squeezed between mica plates are measured. 

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