A Highly Reliable Cu Interconnect Technology for Memory Device

This paper describes the development of Cu interconnect technology for memory devices. A highly reliable sub 50 nm Cu interconnect lines were successfully fabricated by using optimized iPVD barrier/seed and electroplating process. The resistivity of Cu lines was reviewed with that of Al for extendibility of Cu. The Cu TDDB lifetime in user conditions was investigated to confirm the reliability of Cu process integration. It can be predicted that Cu metallization can satisfy the requirements of sub 50 nm trench pattern, which are lower resistance than Al and good reliabilities.