Effect of pore sealing on the reliability of ULK/Cu interconnects

Author

Guedj, C. ; Arnaud, L. ; Fayolle, M. ; Jousseaume, V. ; Guillaumond, J.F. ; Cluzel, J. ; Toffoli, A. ; Reimbold, Gilles ; Bouchu, D.

Author_Institution

CEA-DRT-LETI/DTS-CEA/GRE, Grenoble, France

fYear

2004

Firstpage

148

Lastpage

150

Abstract

The combination of porous ultra low k dielectric and copper metallization is an attractive alternative to meet the requirements of ITRS roadmap concerning the 65 nm interconnection technology, but very little is known about the reliability of such an approach. Porous materials are usually unstable and sensitive to moisture, but pore sealing is a possible strategy to overcome these detrimental effects. In this paper, we have studied the effect of pore sealing on the electrical performance and long-term reliability of ULK/Cu interconnects. The best pore sealing efficiency is obtained for a nominal thickness of 10 nm of a SiC:H sealing layer. With these conditions, the dielectric constant of the ULK is kept at 2.2 even after integration and an electromigration activation energy of 1.2 eV is obtained. The failures mechanisms have been correlated to SEM and FIB analysis.

Keywords

dielectric materials; focused ion beam technology; integrated circuit interconnections; nanoporous materials; reliability; scanning electron microscopy; sealing materials; 1.2 eV; 10 nm; 65 nm; Cu; FIB; ITRS roadmap; SEM; SiC:H; ULK-Cu interconnects; copper metallization; dielectric constant; electromigration activation energy; pore sealing; reliability; ultra low k dielectric; Copper; Dielectric constant; Dielectric materials; Dielectric measurements; Electromigration; Failure analysis; Moisture; Plasma measurements; Plasma temperature; Temperature distribution;

fLanguage

English

Publisher

ieee

Conference_Titel

Interconnect Technology Conference, 2004. Proceedings of the IEEE 2004 International

Print_ISBN

0-7803-8308-7

Type

conf

DOI

10.1109/IITC.2004.1345722

Filename

1345722