Published online by Cambridge University Press: 15 February 2011
Electromigration (EM) void nucleation and growth is a failure mechanism of integrated circuit (IC) metallization. The time-to-failure of interconnect lines depends on the void nucleation time and the void growth time. The current understanding of the void growth stage is minimal, and characterization of the void growth stage is essential to further explain EM performance of IC metal interconnections. This work used high-resolution electron-beam lithography to define small dimension edge-voids into gold lines at various separation distances from each other, on the same side or opposite sides of the lines. The EM-induced interaction behavior of pre-defined voids was measured in a FESEM in-situ. Results showed that for small separation distances, void-void interaction enabled shape changes in the pre-patterned voids. For larger separation distance, void-void interactions could be characterized by secondary, induced void and hillock area measurements. As the separation distance increased, the void-void interaction diminished, and the voids acted independently of each other.