Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-02T23:30:19.031Z Has data issue: false hasContentIssue false
  • English
  • Français

Impact of Microstructure of Alternative Al-Si-V-Pd Alloy Films on Interconnect Reliability, Compared to Al-Si-Cu

Published online by Cambridge University Press:  25 February 2011

A.G. Dirks ,
R.A. Augur ,
S. Kordić  and
R.A.M. Wolters
A.G. Dirks
Affiliation:
Philips Research Laboratories, Prof. Holstlaan 4, 5656 AA Eindhoven, The Netherlands
R.A. Augur
Affiliation:
Philips Research Laboratories, Prof. Holstlaan 4, 5656 AA Eindhoven, The Netherlands
S. Kordić
Affiliation:
Philips Research Laboratories, Prof. Holstlaan 4, 5656 AA Eindhoven, The Netherlands
R.A.M. Wolters
Affiliation:
Philips Research Laboratories, Prof. Holstlaan 4, 5656 AA Eindhoven, The Netherlands
Get access

Abstract

Difficulty during plasma etching and post-etch corrosion are major drawbacks of Al-Si-Cu alloy films, when used for integrated circuit interconnect. Moreover, the relatively large solute mobility of Cu in Al may lead to void formation by precipitate coarsening. As integrated circuit dimensions decrease reliability issues, such as electromigration and mechanical stress voiding, are becoming increasingly important. At present several types of Al alloys are considered as possible alternatives for Al-Si-Cu: Al-Pd, Al-Sc, Al-Pd-Cu, Al-Si-Pd, Al-Si-V, Al-Si-Sc, Al-Si-Pd-Nb, and Al-Si-V-Pd. The latter quaternary alloy has been designed such as to combine the positive aspects of both Pd and V. In comparison with Cu in Al, a) the (low temperature) solid solubility is negligible for Pd and small for V, and b) the mobility is similar for Pd, but very small for V.

With transmission-electron microscopy, passivated Al-Si-Cu alloy films have been studied after thermal stressing at 200 °C: ө-Al2Cu coarsening was observed together with void condensation. Lifetests on unpassivated Al-Si-V-Pd alloys at 180 °C and 2xl06A/cm2 have shown an extremely high resistance to electromigration. Electromigration and microstructural data on these quaternary alloys will be presented. These findings suggest how the microstructure is stabilized by the combined action of the V and Pd solute atoms, a) by nm-scale (A1,V) precipitates within the Al grains and b) by small (Al,Pd) particles at the Al grain boundaries. Furthermore, the key issues in terms of reliability related microstructural phenomena are both solute and solvent mobilities in grain interiors as well as along interfaces and grain boundaries. Arguments will be given showing that at low solute concentrations the metals (V and Pd) each by themselves are not effective enough to influence the solvent motion of aluminium along interfaces and grain boundaries significantly. The combination of the two metals, however, was found to be very effective.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 337: Symposium B – Advanced Metallization for Devices and Circuits—Science, Technology and Manufacturing III , 1994 , 237
Copyright
Copyright © Materials Research Society 1994

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

1 Papers in Materials Reliability in Microelectronics III, edited by Rodbell, K.P., Filter, W.F., Frost, H.J., and Ho, P.S., (Mater. Res. Soc. Proc. 309, Pittsburgh, PA, 1993)Google Scholar
2 Papers in Thin Films: Stresses and Mechanical Properties IV, edited by Townsend, P.H., Weihs, T.P., Sanchez, J.E., and Borgesen, P., (Mater. Res. Soc. Symp. Proc. 308, Pittsburgh, PA, 1993)Google Scholar
3 Kwok, T. and Ho, P.S., in Diffusion Phenomena in Thin Films and Microelectronic Materials, edited by Gupta, D. and Ho, P.S., Noyes, Park Ridge, NJ (1988) p. 369 Google Scholar
4 Kim, C. and Morris, J.W., J. Appl. Phys. 72, 1837 (1992)CrossRefGoogle Scholar
5 Knorr, D.B., Tracy, D.P., and Rodbell, K.P., Appl. Phys. Lett. 59, 3241 (1991)CrossRefGoogle Scholar
6 Cho, J. and Thompson, C.V., Appl. Phys. Lett. 54, 2577 (1989), J. Electronic Mater. 19, 1207 (1990)CrossRefGoogle Scholar
7 Vaidya, S. and Sinha, A.K., Thin Solid Films 75, 253 (1981)CrossRefGoogle Scholar
8 Longworth, H.P. and Thompson, C.V., J. Appl. Phys., 69, 3929 (1991)CrossRefGoogle Scholar
9 Rodbell, K.P., Knorr, D.B., and Mis, J.D., J. Electronic Mater., 22, 597 (1993)CrossRefGoogle Scholar
10 Koubuchi, Y., Onuki, J., Fukuda, S., and Suwa, M., IEEE Trans. on Electron Devices 37, 947 (1990)CrossRefGoogle Scholar
11 Koubuchi, Y. and Onuki, J., IEEE Trans. on Electron Devices 37, 1259 (1990)CrossRefGoogle Scholar
12 Koubuchi, Y., Onuki, J., Suwa, M., Fukuda, S., Moribe, S., and Tanigaki, Y., J. Vac. Sci. Techn. B8, 1232 (1990)CrossRefGoogle Scholar
13 Onuki, J., Koubuchi, Y., Fukuda, S., Suwa, M., IEDM Tech. Dig. 1990 pp. 43–46 Google Scholar
14 Onuki, J., Koubuchi, Y., Suwa, M., Koizumi, M., Gardner, D.S., Suzuki, H., and Minowa, E., IEEE Trans. on Electron Devices 39, 1322 (1992)CrossRefGoogle Scholar
15 Dirks, A.G. and van den Broek, J.J., Scr. Metall. 21, 175 (1987)CrossRefGoogle Scholar
16 van Engelen, P.P.J. and Dirks, A.G., Thin Solid Films 193/194, 999 (1990)CrossRefGoogle Scholar
17 Dirks, A.G. and De Veirman, A.E.M., Scr. Metall. et Mater. 29, 1017 (1993)CrossRefGoogle Scholar
18 Dirks, A.G. and Augur, R.A., Appl. Phys. Lett. 64, 704 (1994)CrossRefGoogle Scholar
19 Dirks, A.G., Augur, R.A., and De Veirman, A.E.M., Thin Solid Films, XXX, 0000 (1994)Google Scholar
20 Ogawa, S. and Nishimura, H., IEDM Tech. Dig. 1991 pp. 277–280 Google Scholar
21 Nishimura, H., Ogawa, S., and Yamada, T., IEDM Tech. Dig. 1993 pp. 281–284 Google Scholar
22 Sanchez, J.E., McKnelly, L.T., and Morris, J.W., J. Appl. Phys. 72, 3201 (1992)CrossRefGoogle Scholar
23 Massalski, T.B., Murray, J.L., Bennett, L.H., and Baker, H., Binary Alloy Phase Diagrams, (American Soc. for Met., Metals Park, OH, 1986) pp. 103, 148, 164, 179Google Scholar
24 Brandes, E.A., in Smithells Metals Reference Book, (Butterworths, London, 1983) p. 13–14 Google Scholar
25 Adda, Y. and Philibert, J., La Diffusion dans les Solides, (Inst. Nat. des Sciences et Techn. Nucl., Saclay, 1966), Vol. II, p. 1149 Google Scholar
26 Samsonov, G.V., Handbook of the Physicochemical Properties of the Elements, (IFI / Plenum, New York, NY, 1968) p. 293 CrossRefGoogle Scholar
27 Kordic, S., Wolters, R.A.M., and Troost, K.Z., J. Appl. Phys. 74, 5391 (1993)CrossRefGoogle Scholar
28 Venables, J.A. and Harland, C.J., Phil. Mag. 27, 1193 (1973)CrossRefGoogle Scholar
29 Kim, C. and Morris, J.W., J. Appl. Phys. 73, 4885 (1993)CrossRefGoogle Scholar
30 Knorr, D.B., in Materials Reliability in Microelectronics III, edited by Rodbell, K.P., Filter, W.F., Frost, H.J., and Ho, P.S., (Mater. Res. Soc. Proc. 309, Pittsburgh, PA, 1993) pp. 75–86 Google Scholar
31 Sanchez, J.E. and Arzt, E., in Materials Reliability in Microelectronics II, edited by Thompson, C.V. and Lloyd, J.R., (Mater. Res. Soc. Proc. 265, Pittsburgh, PA, 1992) pp. 131–142 Google Scholar
32 Sanchez, J.E., McKnelly, L.T., and Morris, J.W., in Phase Transformation Kinetics in Thin Films, edited by M. Chen, M.O. Thompson, R.B. Schwarz, and M. Libera, (Mater. Res. Soc. Proc. 230, Pittsburgh, PA, 1992) pp. 67–72; J. Appl. Phys. 72, 3201 (1992)Google Scholar
33 Tsai, A-P., Inoue, A., and Masumoto, T., Phil. Mag. Lett. 64, 163 (1991)CrossRefGoogle Scholar
34 Mclean, D., in Mechanical Properties of Metals,, (John Wiley & Sons, New York, 1962) pp. 162, 285 Google Scholar
35 Altenpohl, D., in Aluminium und Aluminiumlegierungen, (Springer-Verlag, Berlin, 1965) pp. 505, 830 CrossRefGoogle Scholar
36 Rosenberg, R., J. Vac. Sci. Technol. 9, 263 (1971)CrossRefGoogle Scholar
37 C-K, Hu, Rosenberg, R., and Tu, K.N., in Second International Workshop on Stress Induced Phenomena in Metallization, edited by Ho, P.S., Li, C.-Y., and Totta, P. (American Institute of Physics, New York, 1994), in pressGoogle Scholar
38 C-K, Hu, Small, M.B., Rodbell, K.P., Stanis, C., Blauner, P., and Ho, P.S., Appl. Phys. Lett. 62, 1023 (1993)Google Scholar
39 Arzt, E. and Nix, W.D., J. Mat. Res., 6, 731 (1991)CrossRefGoogle Scholar
40 Arzt, E., Kraft, O., Sanchez, J., Bader, S., and Nix, W.D., 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. Proc. 239, Pittsburgh, PA, 1992) pp. 677–682 Google Scholar
41 Livesay, B.R., Donlin, N.E., Garrison, A.K., Harris, H.M., and Hubbard, J.L., 1992 International Reliability Physics Symposium, (IEEE New York, NY, 1992) pp. 217–227 Google Scholar