Hostname: page-component-7c8c6479df-ph5wq Total loading time: 0 Render date: 2024-03-29T05:02:40.128Z Has data issue: false hasContentIssue false

Investigation of the Homovalent Impurity in Aluminum to Form Alloys With Enhanced Interconnect Reliability

Published online by Cambridge University Press:  10 February 2011

Sridhar K. Kailasam
Affiliation:
Center for Advanced Interconnect Science and Technology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
S. P. Murarka
Affiliation:
Center for Advanced Interconnect Science and Technology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
M. E. Glicksman
Affiliation:
Center for Advanced Interconnect Science and Technology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
S. M. Merchant
Affiliation:
Lucent Technologies, Bell Laboratories, Orlando, FL 32819, USA.
Get access

Abstract

Diffusion-induced failures such as stress-induced voiding and electromigration (EM) are a major concern for interconnect metallization in silicon integrated circuits. The addition of solute elements to aluminum interconnects often leads to “blocking” of high diffusivity paths such as grain boundaries and thus to an improvement in the resistance to electromigration failure. This research investigates Al-In, Al-La, and Al-In-La alloys to improve interconnect EM resistance. The choice of these alloying elements is based on the fact that they have negligible solid solubility in aluminum and are homovalent. Lower solubilities may lead to grain boundary stuffing and hence to improved EM resistance. In addition, the homovalency minimizes the adverse effect on the metal resistivity from addition of impurities to aluminum. Multicomponent diffusion principles are used to tailor aluminum-based ternary alloy compositions which would exhibit the multicomponent effect of zero flux planes (ZFPs), or regions in the reaction zone of a diffusion couple where the flux of a component goes to zero. This study involves modeling the occurrence of ZFPs for aluminum in several diffusion couples of Al-In-La, thus limiting the bulk diffusive spreading of aluminum so that the electromigration behavior can be inhibited or eliminated. This paper presents our experimental findings and discusses the modeling approach to determine ternary alloys exhibiting ZFPs.

Type
Research Article
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

REFERENCES

Jeng, I. S. P., Havemann, R. H., and Chang, M.-C., In Advanced Metallization For Devices And Circuits--Science, Technology And Manufacturability, edited by Murarka, S. P., Katz, A., Tu, K. N., Maex, K., (Mater. Res. Soc. Proc., 337, Pittsburgh, PA, 1994) p. 2531.Google Scholar
2. Joshi, A., Gardner, D., Lu, H. S., Mardinly, A. J., and Nieh, T. G., J. Vac. Sci. Technol. A, 8 (3), 1480 (May/Jun 1990).10.1116/1.576861Google Scholar
3. Lee, Y. K., Fujimura, N., Ito, T., and Nishida, N., J. Vac. Sci. Technol. B, 9 (5), 2542 (Sep 1996).10.1116/1.585689Google Scholar
4. Onoda, H., Takahashi, E., Madokora, S., Fukuyo, H., and Sawada, S., Jpn J. App.l. Phys., 32, Part I, No 11 A, 4934 (1993).Google Scholar
5. Kim, C., Kang, S. H., Génin, F. Y., and Morris, J. W. Jr., In Materials Reliability In Microelectronics V, edited by Oates, A. S., Filter, W. F., Rosenberg, R., Greer, A. L., Gadepally, K., (Mater. Res. Soc. Proc., 391, Pittsburgh, PA, 1995) pp. 289294.Google Scholar
6. Takayama, S., and Tutsui, N.,, J. Vac. Sci. Technol. B, 14 (5), 3257 (Sep/Oct 1996).Google Scholar
7. Darken, L. S., Trans. Am. Inst. Mining Met. Engrs, 180, 430 (1949).Google Scholar
8. Dayananda, M. A. and Kim, C. W., Met. Trans A, 10A, 1333 (Sept. 1979).10.1007/BF02811989Google Scholar
9. Nicolet, M. A., Thin Solid Films, 52, 1431 (1977).Google Scholar
10. Thompson, M. S. and Morral, J. E., Acta Metall., 34 (11), 2201 (1986).Google Scholar
11. Murray, J. L., in Binary Alloy Phase Diagrams, edited by Massalski, T. B., Murray, J. L., Bennett, L. H., and Baker, H. (ASM International, Materials Park, Ohio, 1990) pp. 121124; K. A. Gschneider, Jr. And F. W. Calderwood, ibid., pp. 125–127.Google Scholar
12. Schut, R. J. and Cooper, A. R., Acta Metall, 30, 1957 (1982).Google Scholar