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Aluminum thin film targets, which are laser-induced back-ablated by 1064 nm, 10 ns pulses, and their time-integrated reflectivity have been studied. The model used for analysis includes Al surface removal and the possible production of Al plasma. Plasma reflectance contribution was negligible for plasma electron densities of critical density below 0.3.

Plastic deformation in submicron wide A1-1 wt % copper interconnects has been studied in situ. A straining device in the transmission electron microscope was used. Heterogeneous void nucleation was seen on straining to a critical limit. It appears that plastic deformation was restricted in confined metal lines. Results show void nucleation involves relief of thermal stresses in submicron interconnects.

A series of parallel aluminum lines embedded in silicon dioxide are analyzed using finite element analyses. Numerical results for evolution of thermal stresses are given. Maximum stresses in periodically arranged aluminum lines do not show up when the line width and the line height are about equal. This is not found when the single-line approach is used. Variation of stresses with line aspect ratio is affected by spacing of lines.

A one-dimensional diffusion model is used to study the phenomenon of electromigration-induced edge drift in a finite Al-Cu thin-film conductor. Edge drift seems to begin nearly as soon as the precipitate-free zone length is greater than the Blech length for the line. It seems the presence of Al(sub.2)Cu precipitates in the grain boundaries is required to retard Al electromigration.