THERMAL STRESS-INDUCED AND ELECTROMIGRATION-INDUCED VOID-OPEN FAILURES IN AL AND AL-CU FINE LINES

Thermal stress-induced and electromigration-induced void-open failures in Al and Al-Cu fine lines have been studied. The extra thermal stress induced by temperature cycling shortens the electromigration lifetime of both Al and Al-Cu fine lines by more than an order of magnitude. Our data indicate that there is a approximately 15% reduction in the electromigration resistance of Al fine lines without visual damage after temperature cycling, which may be caused by the subtle structure damage. Our results also show that the addition of Cu in Al fine lines improves the resistance to thermal stress-induced failures, probably by the suppression of grain boundary sliding and migration.