The analysis of thin films, coatings and layered structures is a special part of surface analysis. The film thickness can vary from the millimeter range down to only a few nanometers. Sometimes the studies have to be done very local, insinde an area of interest.
In other cases a large homogeneous surface has to be examined. Depending on the question the elementary principal components or only small traces of contaminations or additives are of interest.
Such surface layers can be studied either directly from the surface. In this case the morphology, topography and the surface chemical composition can be found out.
By using sputtering techniques, also a depth dependent analysis of the surface or the top layers can be done. Usually this procedure is referred to as sputter depth profiling. Typicall analytical techniques are X-Ray Photo Electron Spectroscopy (XPS), Secondary Ion Mass Spectrometry (TOF-SIMS), and glow discharge spectroscopy (GDOS) .
In other cases, it it more helpfull to prepare a cross-section of the sample to examine the desired layer properties directly at this section. Preparation techniques used here are metallographic sections or microtomy / ultramicrotomy cuts. In specific cases also FIB cuts can be prepared and investigated. These cross sections can be studied with a variety of analytical techniques.