| Failure due to electromigration is one of the limiting factors encountered in reliability of integrated circuits. The key to fully understanding the morphological changes in metal interconnect lines in the presence of an electric field is to account for the variations of the electromigration flux as a function of the underlying factors, such as the microstructure. Although there is significant experimental and numerical simulation evidence documenting that grain structure is related to electromigration damage, a general analytical treatment that can explicitly account for such microstructure is lacking. In the present study the perturbation method is employed for the first time to the electromigration process in order to develop a general analysis of how morphological stability is correlated to microstructure induced spatial variations in the effective diffusivity. |
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