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Low Temperature Direct Cu-Cu Immersion Bonding for 3D Integration

Published online by Cambridge University Press:  31 January 2011

Rahul Agarwal  and
Wouter Ruythooren
Rahul Agarwal
Affiliation:
[email protected], IMEC, Interconnect and Packaging, Heverlee, Belgium
Wouter Ruythooren
Affiliation:
[email protected], IMEC, Wet processing Epi Assembly, Heverlee, Belgium
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Abstract

High yielding and high strength Cu-Cu thermo-compression bonds have been obtained at temperatures as low as 175°C. Plated Cu bumps are used for bonding, without any surface planarization step or plasma treatment, and bonding is performed at atmospheric condition. In this work the 25μm diameter bumps are used at a bump pitch of 100μm and 40μm. Low temperature bonding is achieved by using immersion bonding in citric acid. Citric acid provides in-situ cleaning of the Cu surface during the bonding process. The daisy chain electrical bonding yield ranges from 84%-100% depending on the bonding temperature and pressure.

Keywords

bondingCupackaging
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1156: Symposium D – Materials, Processes and Reliability for Advanced Interconnects for Micro-and Nanoelectronics–2009 , 2009 , 1156-D08-02-F06-02
Copyright
Copyright © Materials Research Society 2009

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References

1 Zhang, W., Ruythooren, W., “Study of the Au/In reaction for Transient liquid-phase bonding and 3D chip stacking,” Journal of Electronic Material, vol. 37, no. 8, 2008, pp. 1095–1101.Google Scholar
2 Bosco, N. S., and Zok, W. F., “Critical interlayer thickness for transient liquid phase bonding in the Cu-Sn system,” Acta Materialia, vol. 52, issue 10, 2004, pp. 2965–2972.Google Scholar
3 Gueguen, P., Di, C., Rivoire, M., Scevola, D., Zussy, M., Charvet, A. M., Bally, L., Laforn, D., Clavelier, L., “Copper direct bonding for 3D integration,” International Interconnect Technology Conference, 2008, pp. 61–63.Google Scholar
4 Ruythooren, W., Beltran, A., Labie, R., “Cu-Cu Bonding Alternative to Solder based Micro-Bumping,” Electronics Packaging Technology Conference, 2007, pp. 315–318.Google Scholar
5 Arai, K., Kawai, A., Mizukoshi, M., Uchimura, H., “A new planarization technique by high precision diamond cutting for packaging”, International Symposium on Semiconductor Manufacturing, 2004, pp. 534–537.Google Scholar
6 Kim, T. H., Howlarer, M. M. R., Itoh, T., Suga, T., “Low temperature direct Cu-Cu bonding with low energy ion activation method,” Electronic Materials and Packaging, 2001, pp. 193–195.Google Scholar