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Phase Formation in Cu(Sn) Alloy Thin Films

Published online by Cambridge University Press:  15 February 2011

L. A. Clevenger
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598 [email protected]
B. Arcot
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
W. Ziegler
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
E. G. Colgan
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
Q. Z. Hong
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
F. M. d'Heurle
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
C. Cabral Jr
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
T. A. Gallo
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
J. M. E. Harper
Affiliation:
IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598
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Abstract

The interdiffusion of Cu and Sn and the formation and dissolution of Cu-Sn precipitate phases have been examined for Cu(Sn) alloy thin films. Cu(Sn) films were deposited by electron beam evaporation in either a Sn/Cu bilayer or Cu/Sn/Cu trilayer film structure, with overall Sn concentrations from 0.1 to 5 atomic percent. Analysis by in situ resistivity, calorimetry, electron diffraction and x-ray diffraction measurements indicates that the bilayer and trilayer films form the intermetallic phase η-Cu6 Sn5 during film deposition. Upon heating, the ε-Cu3Sn phase forms at 170°C, then this phase dissolves into the Cu matrix at approximately 350°C. Finally, ζ- Cu10Sn3 phase forms and precipitates after heating to 500°C and cooling to room temperature. The final resistivity of Cu/Sn/Cu films with more than 2 atomic percent Sn was greater than 3.5 μΩ - cm. However, resistivities from 1.9 to 2.5 μΩ - cm after annealing were obtained with Cu/Sn/Cu films containing less than 2 atomic percent Sn.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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References

1) Li, J., Shacham-Diamand, Y., Mayer, J. W. and Colgan, E., Proc. IEEE VLSI Multilevel Interconnection Conference, p. 153 (1991)Google Scholar
2) Small, M. B. and Pearson, D. J., IBM J. Res. Develop., 34, 858 (1990)Google Scholar
3) Harper, J. M. E., Colgan, E. G., Hu, C. K., Hummel, J., Buchwalter, L. P. and Uzoh, C. E., MRS Bulletin, 19, 23 (1994)Google Scholar
4) Lee, K. L., Hu, C. K. and Tu, K. N., J. Appl. Phys. 78, 4428.(1995)Google Scholar
5) Hu, C. K., Luther, B., Kaufmnan, F. B., Hummel, J., Uzoh, C. and Pearson, D. J., Thin Solid Films 262, 84 (1995)Google Scholar
6) Varschavsky, A., J. Mater. Sci., 26, 3603 (1991)Google Scholar
7) Tu, K. N. and Thompson, R. D., Acta Met., 30,947 (1982)Google Scholar
8) JCPDS 4–836, 2–713, 1–1240, 26–564, 30–510Google Scholar