Electromigration in multi-level interconnects with polymeric low-k interlevel dielectrics

Electromigration (EM) characteristics were evaluated on multi-level Al(Cu) test structures with polymeric low k and standard oxide interlevel dielectrics. The two polymers used as interlevel dielectrics in this work are a fluorinated polyimide (FPI) and a poly(aryl) ether(PAE). Joule heating experiments and microstructural analysis were both conducted on Al(Cu) to insure that that there were no microstructural or other differences between the polymer samples and their oxide counterparts. The results show that the integration of polymeric low k dielectrics has a significant impact on EM performance of interconnect structures.