Secondary Ion Mass Spectrometry as Related to Surface Analysis

Abstract Many important processes, such as corrosion, catalysis, adhesion, and biocompatibility, depend on the composition of the surface or interfacial region. The focus of this article is surface applications of secondary ion mass spectrometry ( SIMS ). In SIMS, a sample is introduced into an ultrahigh vacuum ( UHV ) chamber and bombarded by a primary ion beam. The impact of the primary ion results in the desorption (sputtering) of neutral species, electrons, and secondary ions from the surface of the sample. The secondary ions are mass‐analyzed. SIMS experiments are typically carried out in either a dynamic or a static mode. Historically, the two modes were distinguished on the basis of the primary ion dose ( PID ). Dynamic SIMS uses high PIDs and is generally used for elemental depth‐profiling. Static SIMS uses low PIDs (≤1 × 10 12 ions cm −2 ) and is generally used for the molecular characterization of surfaces; however, the introduction of primary ion cluster sources is extending the static SIMS limit. The advantages of SIMS include high sensitivity, the ability to obtain molecular information, isotopic analysis, imaging, and the analysis of low‐atomic‐number elements such as H and Li.