Electro-Migration Behavior Study on Metal Line Width and Length of AlCu Interconnects

Package-level electro-migration (EM) performance of AlCu metallization was investigated in this paper. The metal line width & length dependence of J_max were evaluated. Relationships were achieved between reliability performance and structural size. For width dependence, J_max plunged seriously as width increased from sub-micro to about 2 um; Unexpected greater J_max was discovered when width approached 5 um; For length dependence, J_max was increased sharply as metal line became shorter when length was below 100 urn; when length was above 400 um, J_max showed obvious rise with metal line became longer, rather than saturation in previous studies.