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Thermal Stresses in Passivated Copper Interconnects Determined by X-Ray Analysis and Finite Element Modeling

Published online by Cambridge University Press:  22 February 2011

R.P. Vinci ,
E.M. Zielinski  and
J.C. Bravman
R.P. Vinci
Affiliation:
Department of Materials Science, Stanford University, Stanford, CA 94305-2205
E.M. Zielinski
Affiliation:
Department of Materials Science, Stanford University, Stanford, CA 94305-2205
J.C. Bravman
Affiliation:
Department of Materials Science, Stanford University, Stanford, CA 94305-2205
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Abstract

Stresses in passivated copper lines were determined from strains measured using x-ray methods and compared to stresses calculated using finite element methods. Copper lines, 2 µm wide by 0.8 µm thick, were fabricated by DC magnetron sputtering and lift off patterning. The cross section of these lines was trapezoidal, with approximately 50° sidewalls. One set of samples was left bare, the others passivated with Si3N4 in several different thicknesses. Strain was determined using x-rays. Stress was calculated using elastic moduli adjusted for predominantly (111) fiber texture. Elastic-plastic finite element models provided comparisons of the effects of passivation thickness, rectangular and trapezoidal cross section, and mechanical anisotropy due to preferred texture on the hydrostatic stress in a line. A similar model for aluminum also provided a comparison case of stress as a function of passivation thickness.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 338: Symposium – Materials Reliability in Microelectronics IV , 1994 , 289
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1. Nix, W.D., Met. Trans. A 20A, 2217–2245 (1989).Google Scholar
2. Flinn, P.A., J. of the Mat. Res. Soc. 6, 1498 (1991).Google Scholar
3. Vinci, R.P. and Bravman, J. C., in Thin Films: Stresses and Mechanical Properties IV (Mater. Res. Soc. Proc. 308, 1993), pp. 337–341.Google Scholar
4. Jones, S., SPIE Adv. Resist Tech. and Proc. 1086, 555 (1989).Google Scholar
5. Flinn, P.A. and Waychunas, G. A., J. of Vac. Sci. and Tech. B 6, 1749–1755 (1988).Google Scholar
6. Flinn, P.A. and Chiang, C., J. of Appl. Phys. 67, 2927–2931 (1990).Google Scholar
7.MARC Analysis Research Corporation, MARC and MENTAT, version K4.Google Scholar
8. Sauter, A.I., Ph.D. dissertation, Stanford University (1991).Google Scholar
9. , Landolt-Bornstein, Numerical Data and Functional Relationships in Science and Technology, Hellwege, K.-H., Hellwege, A.M., Eds., (Springer-Verlag, Berlin, 1969), Vol. 2.Google Scholar
10. Jones, R.E., in Proceedings of the 25th Annual International Reliability Symposium (IEEE New York, 1987), pp. 9–14.Google Scholar
11. Hosford, W.F., The Mechanics of Crystals and Textured Polycrystals, Oxford Engineering Science Series (Oxford University Press, Oxford, 1993).Google Scholar
12. Sauter, A.I. and Nix, W.D., IEEE Trans. on CHMT 15, 594–600 (1992).Google Scholar
13. Vinci, R.P., Marieb, T.N., and Bravman, J.C., in Thin Films: Stresses and Mechanical Properties IV (Mater. Res. Soc. Proc. 308, Pittsburgh, PA, 1993), pp. 297–302.Google Scholar