Hostname: page-component-8448b6f56d-sxzjt Total loading time: 0 Render date: 2024-04-23T07:38:06.020Z Has data issue: false hasContentIssue false
  • English
  • Français

Via Electromigration Lifetime Improvement of Aluminum Dual-Damascene Interconnects by Using Soft Low-k Organic SOG Interlayer Dielectrics

Published online by Cambridge University Press:  17 March 2011

Hisashi Kaneko ,
Takamasa Usui ,
Sachiyo Ito  and
Masahiko Hasunuma
Hisashi Kaneko
Affiliation:
Process & Manufacturing Engineering Center, TOSHIBA Corp. 8, Shinsugita-cho, Isogo-ku, Yokohama-city, 235-8522, JAPANhisashi.kaneko@toshiba.co.jp
Takamasa Usui
Affiliation:
Process & Manufacturing Engineering Center, TOSHIBA Corp. 8, Shinsugita-cho, Isogo-ku, Yokohama-city, 235-8522, JAPAN
Sachiyo Ito
Affiliation:
Process & Manufacturing Engineering Center, TOSHIBA Corp. 8, Shinsugita-cho, Isogo-ku, Yokohama-city, 235-8522, JAPAN
Masahiko Hasunuma
Affiliation:
Process & Manufacturing Engineering Center, TOSHIBA Corp. 8, Shinsugita-cho, Isogo-ku, Yokohama-city, 235-8522, JAPAN
Get access

Abstract

The via electromigration(EM) reliability of aluminum(Al) dual-damascene interconnects by using Niobium(Nb) new reflow liner is described. It has been found that the via EM lifetime was improved by introducing low-k organic spin on glass(SOG)-passivated structure than the conventional TEOS-SiO2/SiN-passivated structure. Higher EM activation energy of 1.08 eV was obtained for the SOG-passivated structure than the conventional TEOS-passivated structure of 0.9 eV, even though no significant Al micro-crystal structure difference was found for both structures. It has been turned out that the low-k SOG material has the 1/7 Young's modulus (8 GPa) of TEOS-SiO2 (57 GPa) or thermal SiO2(70 GPa). The small Young's modulus means that SOG is more elastically deformable and/or softer than TEOS or thermal SiO2. This elastic deformation of the low-k SOG could retard the tensile stress evolution due to the Al atom migration near the cathode via, and elongated the time until the Al interconnect tensile stress exceeds the critical stress value for void nucleation. It has been concluded that the small-RC and reliable multi-level Al interconnect can be realized by the Nb-liner reflow-sputtered process with soft and low-k SOG dielectric materials.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 612: Symposium D – Materials, Technology & Reliability for Advanced Interconnects.. , 2000 , D2.5.1
Copyright
Copyright © Materials Research Society 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Kaanta, C. W. et al. , “Dual Damascene : A ULSI Wiring Technology”, in Proceedings of International VLSI Multilevel Interconnection Conference, 1991, p.144.Google Scholar
2. Clevenger, L. A. et al. , “A Novel Low Temperature CVD/PVD Al Filling Process for Producing Highly Reliable 0.175[.proportional]m wiring/0.35[.proportional]m Pitch Dual Damascene Interconnections in Gigabit Scale DRAMs”, in Proceedings of International Interconnect Technology Conference, 1998, p. 137.Google Scholar
3. Wada, J. et al. , “Low Resistance Dual Damascene Process by New Al Reflow using Nb Liner”, in Proceedings of IEEE 1998 VLSI Symp. on Technol., 1998, p.48.Google Scholar
4. Edelstein, D. C., Sai-Halasz, G. A. and Mii, Y. J., “VLSI On-Chip Interconnection Performance Simulation and Measurements”, IBM J. Res. Develop., 39, p. 383, 1995.10.1147/rd.394.0383Google Scholar
5. Nakata, R. et al. , “New Low-k Material “LKD TM ” for Al Damascene Process Application”, Extended Abstracts of the 1999 International Conference on Solid State Devices and Materials, Tokyo, 1999, pp. 506–507.Google Scholar
6. Harper, J. M. E. and Rodbell, K. P., “Microstructure Control in Semiconductor Metallization”, J. Vac. Sci. Technol, B15, 1997, p. 763.10.1116/1.589407Google Scholar
7. Hurd, J. L. et al. , “Linewidth and underlayer influence on texture in submicrometer-wide Al and AlCu lines”, Appl. Phys. Lett., 72, 1998, p.326.10.1063/1.120726Google Scholar
8. Furuya, A. et al. , “Electrical Characterization and Microstructure of 0.32[.proportional]m-Pitch Aluminum-Damascene Interconnects”, in Advanced Metallization Conference in 1998 Japan/Asia Session, 1998, p.33.Google Scholar
9. Sanchez, J. E., Besser, P. R. and Field, D. P., “Microstructure of Damascene Processed Al-Cu Interconnects for Integrated Circuit Applications”, in AIP Conference Proceedings of the Fourth International Workshop on Stress-Induced Phenomena in Metallization 418, 1997, p. 230.Google Scholar
10. Foley, S. et al. , “A Study of the Influence of Inter-Metal Dielectrics on Electromigration Performance”, Microeletron. Reliab., 38, 1998, p. 107.10.1016/S0026-2714(97)00075-9Google Scholar
11. Ho, P. S., Wang, P. H. and Kasthurigrangan, J., “Structure Integrity and Reliability of Low K Interconnects”, in Advanced Metallization Conference in 1998 Japan/Asia Session, 1998, p.19.Google Scholar
12. Usui, T. et al. , “Significant Improvement in Electromigration of Reflow-Sputtered Al-0.5wt%Cu/Nb-liner Dual Damascene Interconnects with Low-k Organic SOG Dielectric”, in Proceedings of 37th International Reliability Physics Symposium, 1999, p.221.Google Scholar
13. Blech, I. A., J. Appl. Phys., 47, 1976, p. 1203.10.1063/1.322842Google Scholar
14. Hu, C. K., Small, M. B. and Ho, P. S., “Electromigration in Al (Cu) two-level structures: effect D2.5.8 of Cu and kinetics of damage formation”, J. Appl. Phys., 74, 1993, p. 969.10.1063/1.354839Google Scholar
15. Kaneko, H. et al. , “A Newly Developed Model for the Stress-induced Slit-like Voiding”, in Proceedings of 28th International Reliability Physics Symposium, 1990, p.194.10.1109/IRPS.1990.363521Google Scholar
16. Korhonen, M. A. et al. , “Stress evolution due to electromigration in confined metal lines”, J. Appl. Phys., 73, 1993, p. 3790.10.1063/1.354073Google Scholar
17. Tezaki, A. et al. , “Measurement of three Dimensional Stress and Modeling of Stress Induced Migration Failure in Aluminum Interconnects”, in Proceedings of 28th International Reliability Physics Symposium, 1990, p. 221.10.1109/IRPS.1990.363525Google Scholar