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Constraint Effects on Thin Film Channel Cracking Behavior

Published online by Cambridge University Press:  03 March 2011

Ting Y. Tsui*
Affiliation:
Silicon Technology Development, Texas Instruments Inc., Dallas, Texas 75246
Andrew J. McKerrow
Affiliation:
Silicon Technology Development, Texas Instruments Inc., Dallas, Texas 75246
Joost J. Vlassak
Affiliation:
Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138
*
a) Address all correspondence to this author. e-mail: ttsui@ti.com This paper was selected as the Outstanding Meeting Paper for the 2005 MRS Spring Meeting Symposium B Proceedings, Vol. 863.
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Abstract

One of the most common forms of cohesive failure observed in brittle thin film subjected to a tensile residual stress is channel cracking, a fracture mode in which through-film cracks propagate in the film. The crack growth rate depends on intrinsic film properties, residual stress, the presence of reactive species in the environments, and the precise film stack. In this paper, we investigate the effect of various buffer layers sandwiched between a brittle carbon-doped-silicate (CDS) film and a silicon substrate on channel cracking of the CDS film. The results show that channel cracking is enhanced if the buffer layer is more compliant than the silicon substrate. Crack velocity increases with increasing buffer layer thickness and decreasing buffer layer stiffness. This is caused by a reduction of the constraint imposed by the substrate on the film and a commensurate increase in energy release rate. The degree of constraint is characterized experimentally as a function of buffer layer thickness and stiffness, and compared to the results of a simple shear lag model that was proposed previously. The results show that the shear lag model does not accurately predict the effect of the buffer layer.

Type
Outstanding Meeting Paper
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1Ma, Q.: A four-point bending technique for studying subcritical crack growth in thin films and at interfaces. J. Mater. Res. 12, 840 (1997).CrossRefGoogle Scholar
2Lane, M., Krishna, N., Hashim, I. and Dauskardt, R.H.: Adhesion and reliability of copper interconnects with Ta and TaN barrier layers. J. Mater. Res. 15, 203 (2000).CrossRefGoogle Scholar
3Tsui, T.Y., Griffin, A.J. Jr., Jacques, J., Fields, R., McKerrow, A.J., and Kraft, R.: Effects of elastic modulus on the fracture behavior of low-dielectric constant films, in Proceedings of the 2005 IEEE International Interconnect Technology Conference (IEEE Electronic Devices Society, Piscataway, NJ, 2005), pp. 6365.Google Scholar
4Volinsky, A.A., Waters, P., Kiely, J.D. and Johns, E.: Sub-critical telephone cord delamination propagation, in Stability of Thin Films and Nanostructures, edited by Vinci, R.P., Schwaiger, R., Karim, A., and Shenoy, V. (Mater. Res. Soc. Symp. Proc. 854E, Warrendale, PA, 2004), U9.5.Google Scholar
5Vlassak, J.J.: Channel cracking in thin films on substrates of finite thickness. Int. J. Fracture 119(4), 299 (2003).CrossRefGoogle Scholar
6Cook, R.F. and Liniger, E.G.: Stress-corrosion cracking of low-dielectric-constant spin-on-glass thin films. J. Electrochem. Soc. 146, 4439 (1999).CrossRefGoogle Scholar
7Beuth, J.L. Jr.: Cracking of thin bonded films in residual tension. Int. J. Solids Struct. 29, 1657 (1992).CrossRefGoogle Scholar
8Dundurs, J.: Edge-bonded dissimilar orthogonal elastic wedges. J. Appl. Mech. 36, 650 (1969).CrossRefGoogle Scholar
9Lawn, B.R.: Fracture of Brittle Solids, 2nd ed. (Cambridge Press, Cambridge, U.K., 1993).CrossRefGoogle Scholar
10Wiederhorn, S.M. and Johnson, H.: Effect of electrolyte pH on crack propagation in glass. J. Am. Ceram. Soc. 56(4), 192 (1973).CrossRefGoogle Scholar
11Courtney, T.H.: Mechanical Behavior of Materials (McGraw-Hill Publishing Company, New York, 1990).Google Scholar
12Suo, Z. Reliability of interconnect structures, in Interfacial and Nanoscale Fracture, Comprehensive Structural Integrity, Vol. 8, edited by Milne, I., Ritchie, R.O., and Karihaloo, B. (Elsevier, Oxford, U.K., 2003), pp. 265324.CrossRefGoogle Scholar
13He, J., Xu, G. and Suo, Z. Experimental determination of crack driving forces in integrated structures, in Proceedings of the 7th International Workshop on Stress-Induced Phenomena in Metallization, edited by Ho, P.S.W., Baker, S.P., Nakamura, T., and Volkert, C.A. (American Institute of Physics, New York, 2004), pp. 314.Google Scholar