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Abstract: An inverse approach to dislocation microstructure analysis is presented, able to provide dislocation density, character of the activated dislocations and range of the corresponding distortion field. It is based on the coupling between the micromechanical dislocation theory (providing the distortion field within a given crystal) with X-ray line profile analysis (relating a distortion field with the broadening of diffraction line profiles). In particular, lattice distortion is calculated by using both the dislocation density tensor (expressing the incompatibility of the microstructure) and the general Green''s function formalism (characterizing the interaction between lattice spatial positions) whereas a Fourier treatment is used to evaluate the X-ray diffraction line broadening. Within the proposed formalism, the case of a periodic arrangement of dislocations is analysed, and numerical simulations, compared with high resolution X-ray diffraction, are shown to provide results quantitatively compatible with literature data both on dislocation density, arrangement and mean distance. [Copyright &y& Elsevier]

An accurate knowledge of the phenomenon is required to develop a predictive modeling of the electromigration failure. Thus, a hitherto unseen SEM in operando observation method is devised. The test structure with “high density” through silicon vias (TSV) is tested at 623 K with an injected current density of 1 MA/cm 2 . Regular shots of micrographs inform about the voids nucleation, forced in copper lines above the TSV, and about the scenario of their evolution. A clear relation is established between voids evolution and the one of the electrical resistance. The lack of impact of test conditions on the failure mechanism is demonstrated. Finally, the impact of microstructure on the depletion mechanism is discussed. Grain boundaries are preferential voids nucleation sites and influence the voids evolution. A probable effect of grain size and crystallographic orientation is revealed. [ABSTRACT FROM AUTHOR]