Secondary Ion Mass Spectrometry as Related to Surface Analysis

Abstract

Abstract Many important processes such as catalysis, corrosion, and adhesion depend on the elemental and molecular composition of the surface or interfacial region. The focus of this article is specifically surface applications of secondary ion mass spectrometry (SIMS). Conceptually, SIMS is a very simple technique consisting of a primary ion bombardment step, an energy transfer step, a particle desorption step, and an ion detection step. SIMS experiments are carried out in either a dynamic or a static mode. The two modes are distinguished on the basis of ion dose. Dynamic SIMS uses high primary ion beam doses and is generally used for elemental depth profiling. Static SIMS uses low primary ion beam doses (≤1 × 10 12 ions cm −2 ) and is generally used for the chemical characterization of surfaces. The major advantages of SIMS include high sensitivity (parts per million detection limits for some elements), the ability to obtain molecular information, isotopic analysis, lateral characterization (imaging), and analysis of low‐atomic‐number elements such as H and Li. These characteristics combine to make SIMS a very powerful analytical tool. The key disadvantages of SIMS are that the instrumentation is relatively expensive and that the data can be complex. Related analytical techniques for surface analysis include X‐ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), Scanning Auger Microscopy (SAM), and laser desorption mass spectrometry (LDMS).