Instrumental techniques for the surface analysis of materials

Surface analysis can be defined as the direct measurement of the chemistry of the outer few atomic layers of a solid. The most commonly-used techniques include Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS) although others provide complementary information and are used in more extensive studies. The aforementioned techniques can be extended by the use of depth profiling methods, to obtain information from beneath the immediate surface, for example, to determine the thickness and composition of overlayers. Surface analytical techniques can provide valuable information in such areas of technology as semiconductors, packaging, catalysis, coatings and metallurgy. In this short review, an introduction will he given to the principles underlying AES, XPS and SIMS. This is followed by a number of case studies which highlight how such techniques can elucidate a number of materials related problems.