A study of electromigration lifetime for Cu interconnects coated with CoWP, Ta/TaN, or SiC _xN _yH _z

Electromigration in Cu Damascene lines capped with a CoWP, Ta/TaN, or SiC xN yH z layer was investigated. A thin CoWP or Ta/TaN cap on top of the Cu line significantly improved the electromigration lifetime when compared with lines capped with SiC xN yH z. Extremely long electromigration lifetimes for Cu lines capped with either CoWP or Ta/TaN were obtained. © 2004 Materials Research Society.