Grain sizes and crystallographic orientations of Cu were analyzed versus linewidth in damascene Cu interconects. Pure bamboo lines were not obtained because grain size decreased as linewidth was reduced. Comparison of electromigration results, for wide line Chemical vapor deposition-Cu (3 μm) polycrystalline structure, and narrow lines (0.5 μm) quasi-bamboo structure, provided almost the same activation energy Ea～0.65 eV, enven though the poor (2 0 0) texture has rotated in the film plane for the narrow damascene lines. These results are in agreemetn with copper diffusion involving surface diffusion. Besides, even with a polycrystalline crystallographic orientation, PVD-Cu samples showed a better activation energy value Ea=1.02 eV.
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