Integration and reliability of Cu-SiOC interconnect for ArF/90-nm node CMOS technology

Cu-SiOC interconnects for ArF/90-nm node technology were investigated. This paper describes the integration and reliability issues. The methods to improve chemical mechanical polishing delamination, SiOC damage and electrical shorts through the bottom interface of Cu interconnects were discussed. Reliability characteristics, such as stress-migration, electro-migration, and time-dependent dielectric breakdown (TDDB) were studied. Cu diffusion with via resistance increase by high-temperature stress, and TDDB degradation due to the ArF process were found. It was confirmed that the suggested integration process was mature and sufficiently reliable for normal operating conditions.