Title :
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
fDate :
27 June-1 July 2005
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;
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
DOI :
10.1109/IPFA.2005.1469137
