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Aluminum Alloy Formation and Impacts in Advanced Replacement Metal Gate Process

Published online by Cambridge University Press:  31 January 2012

K. Xu ,
Y. Wang ,
S.H. Shen ,
X. Xia ,
W.Ch. Tu ,
L. Karuppiah ,
H. Yang ,
Z. Ge ,
Y. Lei  and
M. Allen
...Show all authors
K. Xu
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
Y. Wang
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
S.H. Shen
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
X. Xia
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
W.Ch. Tu
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
L. Karuppiah
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
H. Yang
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
Z. Ge
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
Y. Lei
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
M. Allen
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
N. Yoshida
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
L.W. Chang
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
B. Liu
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
M. Okazaki
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
A. Brand
Affiliation:
Applied Materials, 974E. Arques Ave. Sunnyvale, CA 94085, U.S.A. E-mail: kun_xu@amat.com
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Abstract

For the gate last approach of a high K metal gate scheme used in advanced CMOS technology, various materials were tested as wetting layers to allow Aluminum (Al) gap fill at gate widths of10 to 45 nanometers. In this study, Titanium (Ti) and Cobalt (Co) were investigated as a wetting layer for Al gap fill. It was discovered that Al-Ti and Al-Co alloys were formed during high temperature Al deposition. Alloys were characterized using XRD. Alloy’s impacts on line resistivity and subsequent Al Chemical Mechanical Polish (Al CMP) were also investigated. In addition, a model was established to predict the alloy type and alloy mole% with respect to feature size. The predicted Al mole% by this model correlated very well with 1) line resistivity trend and 2) morphologies. The model also predicted that due to Al lower electro-chemical potential than Ti, Co or its alloys, galvanic corrosion could take place depending on the chemical environment in the Al CMP slurry. Different slurry or cleaning chemical may reduce or increase the risk of galvanic corrosion. The knowledge gained with the help of the model provides clear directions on selection criteria for wetting layers, optimization for deposition processes and Al CMP consumable design to meet the challenges.

Keywords

CMPAlCoTiAlloy
Type
Articles
Information
MRS Online Proceedings Library (OPL) , Volume 1372: Symposium S3 – Structural and Chemical Characterization of Metal Alloys and Compounds—2011 , 2012 , imrc-1372-s3-14
Copyright
Copyright © Materials Research Society 2012

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References

REFERENCES

1. Mistry, K., Allen, C., Auth, C., et al. ., IEDM Tech. Dig. 247–250 (2007).Google Scholar
2. Steigerwald, J.M., IEDM Tech. Dig. 1–4 (2008).Google Scholar
3. Steigerwald, J.M., presented at the International Conference on Planarization/CMP Technology, Fukuoka, Japan, 2009 (unpublished).Google Scholar
4. Feeney, P., Solid State Tech. 54, 10 (2010).Google Scholar
5. Xu, K., Chen, Y., Iravani, H., Wang, Y., Swedek, B., Yu, M., Wang, Y., Tu, W., Xia, S. and Karuppiah, L., ECS Trans. 33, 69–76 (2010).Google Scholar
6. Bradley, L., U.S. Patent No. 6 300 629 (9 October 2001).Google Scholar
7. Colgan, E.G. and Mayer, J.W., J. Mater.Res. 4, 815 (1989).Google Scholar
8. Massalski, T. B., Murray, J.L., Bennett, L. H., Baker, H., Binary Phase Diagrams, Vol. 1 (American Society for Metals, Metals Park, Ohio, 1986) p.102.Google Scholar
9. Al-Ti, Scientific Group Thermodata Europe, Collection of Phase Diagrams, Data from SGTE alloy database, revised 2004, http://www.sgte.org/fact/phase_diagram.php?file=Al-Ti.jpg&dir=SGTE Google Scholar
10. Aylwardand, G. Findlay, T., SI Chemical Data, 4th ed. (John Wiley & Sons, Australia, 1998) p. 130–135.Google Scholar