SPATIALLY-TRANSIENT STRESS EFFECTS IN THIN FILMS BY X-RAY DIFFRACTION

摘要

We present a review of the application of diffraction stress/strain analysis to small volumes. Forrncases in which the material properties and/or the stress state are not homogeneous, traditionalrnapproaches may yield erroneous stress results. On the other hand, with proper care, relevantrnmechanical information about the system can be obtained. Through the use of conventional andrnsynchrotron-based X-ray methods, we can determine the amount of strain transfer between thinrnfilm features that possess heterogeneous stress distributions and the underlying substrate. Twornexamples of such studies are presented. The resulting data is used to assess the validity of severalrnmodels often used to predict the mechanical behavior in thin film/substrate composites.