Stress migration lifetime for Cu interconnects with CoWP-only cap

Author

Gambino, J. ; Johnson, C. ; Therrien, J. ; Hunt, D. ; Wynne, J. ; Smith, S. ; Mongeon, S. ; Pokrinchak, P. ; Levin, T.M.

Author_Institution

IBM Microelectron., Essex Junction, VT, USA

fYear

2005

fDate

27 June-1 July 2005

Firstpage

92

Lastpage

95

Abstract

Stress migration lifetime is characterized for a CoWP-only cap process (i.e. no dielectric cap) and a CoWP + SiN cap process. For the CoWP-only process, the stress migration lifetime depends on the CoWP thickness. In order to achieve a long stress migration lifetime, the CoWP must be sufficiently thick to protect the Cu during the via etch and strip processes. The data suggests that CoWP removal is enhanced beneath partially landed vias, resulting in reduced stress migration lifetime.

Keywords

cobalt compounds; copper; electromigration; integrated circuit interconnections; integrated circuit reliability; silicon compounds; CoWP; CoWP + SiN cap process; CoWP removal; CoWP-only cap; Cu; Cu interconnects; SiN; etch process; stress migration lifetime; strip process; Capacitance; Copper; Dielectrics; Integrated circuit interconnections; Microelectronics; Scanning electron microscopy; Silicon compounds; Stress; Strips; Transmission electron microscopy;

fLanguage

English

Publisher

ieee

Conference_Titel

Physical and Failure Analysis of Integrated Circuits, 2005. IPFA 2005. Proceedings of the 12th International Symposium on the

Print_ISBN

0-7803-9301-5

Type

conf

DOI

10.1109/IPFA.2005.1469137

Filename

1469137