THE SMALL-ANGLE CLEAVAGE TECHNIQUE APPLIED TO COATINGS AND THIN-FILMS

Sample preparation for cross-sectional examination of coatings and thi n films by transmission electron microscopy (TEM) is the most critical step of this characterization technique. Without a sufficiently thin sample with a minimum of artifacts, some of the high-resolution imagin g and analytical techniques available in the modern analytical TEM can not be utilized. Frequently, the cross-sectional TEM (XTEM) sample pre paration step requires special instrumentation, extensive technical sk ills, and long lead times. The small angle cleavage technique (SACT) h as been successfully applied to various semiconductor materials. It ha s the advantage of being a very fast, inexpensive, and easy technique for XTEM sample preparation. In addition, it produces a sample with ve ry clean surfaces without ion milling. In this paper, the technique wi ll be briefly described. The technique can be easily accommodated into any specimen preparation laboratory. Results for single-layered and m ulti-layered coatings and thin films deposited on semiconductor and no n-semiconductor substrates including Si, GaAs, sapphire, quartz, SiC, and glass are shown to illustrate the flexibility of the technique. Th e technique does not always work. Examples of materials systems in whi ch it was not possible to make a suitable sample are given, and the re asons for the failure are discussed. Published by Elsevier Science S.A .