Transmission electron microscopy characterization of hard coatings and films: Sample preparation aspects and results

The theory of surface morphology development during small-angle ion milling of samples for transmission electron microscopy is discussed from the point of view of preparing samples of a hard material in contact with a softer material. The basic points of the mechanical preparation and the ion-milling arrangement are also listed. Samples of hard films on substrates (diamond/Si, SiC/Si and TiN/Si) as well as a fiber composite (SiC in plastic) and mechanically alloyed powders are shown to illustrate the power of the technique.