Hostname: page-component-745bb68f8f-b95js Total loading time: 0 Render date: 2025-01-27T01:28:00.091Z Has data issue: false hasContentIssue false
  • English
  • Français

Quantitative analysis of strengthening mechanisms in thin Cu films: Effects of film thickness, grain size, and passivation

Published online by Cambridge University Press:  31 January 2011

R-M. Keller ,
S. P. Baker  and
E. Arzt
R-M. Keller
Affiliation:
Max-Planck-Institut für Metallforschung, and Institut für Metallkunde, University of Stuttgart, Seestrasse 71, D-70174 Stuttgart, Germany
S. P. Baker
Affiliation:
Max-Planck-Institut für Metallforschung, and Institut für Metallkunde, University of Stuttgart, Seestrasse 71, D-70174 Stuttgart, Germany
E. Arzt
Affiliation:
Max-Planck-Institut für Metallforschung, and Institut für Metallkunde, University of Stuttgart, Seestrasse 71, D-70174 Stuttgart, Germany
Get access

Abstract

Thermal stresses in thin Cu films on silicon substrates were examined as a function of film thickness and presence of a silicon nitride passivation layer. At room temperature, tensile stresses increased with decreasing film thickness in qualitative agreement with a dislocation constraint model. However, in order to predict the stress levels, grain-size strengthening, which is shown to follow a Hall–Petch relation, must be superimposed. An alternative explanation is strain-hardening due to the increase in dislocation density, which was measured by x-ray diffraction. At 600 °C, the passivation increases the stress by an order of magnitude; this leads to a substantially different shape of the stress-temperature curves, which now resemble those of aluminum with only a native oxide layer. The effect of passivation is shown to be very sensitive to the deposition and test conditions.

Type
Articles
Information
Journal of Materials Research , Volume 13 , Issue 5 , May 1998 , pp. 1307 - 1317
Copyright
Copyright © Materials Research Society 1998

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.Flinn, P. A., J. Mater. Res. 6, 1498 (1991).CrossRefGoogle Scholar
2.Vinci, R. P., Thermal Strains and Stresses in Copper Thin Films and Microelectronic Interconnect Structures, Ph.D. dissertation, Stanford University (1994).Google Scholar
3.Zielinski, E. M., Vinci, R. P., and Bravman, J. C., J. Electron. Mater. 24 (10), 1485–1492 (1995).CrossRefGoogle Scholar
4.Doerner, M. F. and Nix, W. D., Solid State and Materials Sciences 14 (3), 225–268 (1988).Google Scholar
5.Nix, W. D., Metall. Trans. A 20A, 2217–2245 (1989).CrossRefGoogle Scholar
6.Venkatraman, R. and Bravman, J. C., J. Mater. Res. 7, 2040–2048 (1992).CrossRefGoogle Scholar
7.Freund, L. B., J. Appl. Mechanics 54, 553–557 (1987).CrossRefGoogle Scholar
8.Venkatraman, R. and Bravman, J. C., in Thin Films: Stresses and Mechanical Properties III, edited by Nix, W. D., Bravman, J. C., Arzt, E., and Freund, L. B. (Mater. Res. Soc. Symp. Proc. 239, Pittsburgh, PA, 1992), pp. 127–132.Google Scholar
9.Keller, R-M., Baker, S. P., Kretschmann, A., Vinci, R. P., and Arzt, E., unpublished.Google Scholar
10.Flinn, P. A., Gardner, D. S., and Nix, W. D., IEEE Trans. Electron Devices 34 (3), 689–699 (1987).CrossRefGoogle Scholar
11. The Texwipe Company, 650 East Crescent Avenue, PO.Box 575, Upper Saddle River, New Jersey 07458, TechniCloth II.Google Scholar
12.Flinn, P. A., private communication.Google Scholar
13.Stoney, G. G., Proc. R. Soc. A82, 172–175 (1909).Google Scholar
14.von Preissig, F. G., J. Appl. Phys. 66 (9), 4262–4268 (1989).CrossRefGoogle Scholar
15.Kuschke, W. M., Kretschmann, A., Keller, R-M., Vinci, R. P., Kaufmann, C., and Arzt, E., J. Mater. Res. (in press).Google Scholar
16.Kretschmann, A., Ph.D. dissertation, University of Stuttgart (1997).Google Scholar
17.Keller, R-M., Kuschke, W-M., Kretschmann, A., Bader, S., Vinci, R. P., and Arzt, E., in Materials Reliability in Microelectronics V, edited by Oates, A. S., Filter, W. F., Rosenberg, R., Greer, A. L., and Gadepally, K. (Mater. Res. Soc. Symp. Proc. 391, Pittsburgh, PA, 1995), pp. 309–314.Google Scholar
18.Keller, R-M., Baker, S. P., and Arzt, E., unpublished.Google Scholar
19.Doerner, M. F., Gardner, D. S., and Nix, W. D., J. Mater. Res. 1, 845–851 (1986).CrossRefGoogle Scholar
20.Keller, R-M., Thermomechanisches Verhalten und Mikrostruktur dünner, polykristalliner Kupferschichten, Ph.D. dissertation, University of Stuttgart (1996).Google Scholar
21.Courtney, T. H., Mechanical Behavior of Materials (McGraw-Hill, New York, 1990), p. 171.Google Scholar
22.Gertsman, V. Y., Hoffmann, M., Gleiter, H., and Birringer, R., Acta Metall. Mater. 42 (10), 3539–3544 (1994).CrossRefGoogle Scholar
23.Chaudhari, P., Philos. Mag. A 39 (4), 507–516 (1979).CrossRefGoogle Scholar
24.Courtney, T. H., Mechanical Behavior of Materials (McGraw-Hill, New York, 1990), p. 167.Google Scholar
25.Chauduri, J., Thokala, R., Edgar, J. H., and Sywe, B. S., Thin Solid Films 274, 23–30 (1996).CrossRefGoogle Scholar
26.Keller, R-M., Sigle, W., Baker, S. P., Kraft, O., and Arzt, E., in Thin Films: Stresses and Mechanical Properties VI, edited by Gerberich, W. W., Gao, H., Sundgrer, J-E., and Baker, S. P. (Mater. Res. Soc. Symp. Proc. 436, Pittsburgh, PA, 1997).Google Scholar
27.Li, J. C. M., Trans. Metall. Soc. AIME 227, 239–247 (1963).Google Scholar
28.Frost, H. J. and Ashby, M. F., Deformation-Mechanism Maps: The Plasticity and Creep of Metals and Ceramics (Pergamon Press, Oxford, 1982), pp. 6–16.Google Scholar
29.Bader, S., Flinn, P. A., Arzt, E., and Nix, W. D., J. Mater. Res. 9, 318–327 (1994).CrossRefGoogle Scholar
30.Vinci, R. P., Zielinski, E. M., and Bravman, J. C., Thin Solid Films 262, 142–153 (1995).CrossRefGoogle Scholar
31.Venkatraman, R., Chen, S., and Bravman, J. C., J. Vac. Sci. Technol. A9, 2536–2542 (1991).CrossRefGoogle Scholar
32.Gardner, D. S. and Flinn, P. A., IEEE Trans. Electron Devices 35 (12), 2160–2169 (1988).CrossRefGoogle Scholar
33.Venkatraman, R., Bravman, J. C., Nix, W. D., Davies, P. W., Flinn, P. A., and Fraser, D. B., J. Electron. Mater. 19, 1231–1237 (1990).CrossRefGoogle Scholar
34.Venkatraman, R., Plasticity and Flow Stresses in Aluminum Thin Films on Silicon, Ph.D. dissertation, Stanford University (1992).Google Scholar