Hostname: page-component-76fb5796d-22dnz Total loading time: 0 Render date: 2024-04-26T00:01:29.424Z Has data issue: false hasContentIssue false
  • English
  • Français

Formation of AlxOyNz Barriers for Advanced Silver Metallization

Published online by Cambridge University Press:  17 March 2011

Y. Wang  and
T.L. Alford
Y. Wang
Affiliation:
Department of Chemical, Bio, and Materials Engineering NSF Center for Low Power Electronics Arizona State University, Tempe, AZ 85287-6006, USA
T.L. Alford
Affiliation:
Department of Chemical, Bio, and Materials Engineering NSF Center for Low Power Electronics Arizona State University, Tempe, AZ 85287-6006, USA
Get access

Abstract

Silver has been explored as a potential candidate for future advanced interconnects due to its lowest electrical resistivity, when compared with Al and Cu. As in the case of Cu metallization, an additional layer between the Ag film and underneath dielectric is necessary in order to improve adhesion and to block the diffusion of Ag atoms. In this study, thin aluminum oxynitride (AlxOyNz) diffusion barriers have been formed in the temperature range of 400-725 °C by annealing Ag/Al bilayers on oxidized Si substrates in ammonia ambient. Rutherford backscattering spectrometry showed that the out-diffused Al reacted with both the ammonia and oxygen in the ambient and encapsulated the Ag films. Higher process temperatures and thinner original Al layers showed to improve the resistivity of the encapsulated Ag layers. The resulting Ag resistivity values are ∼1.75 ± 0.35 µΩ-cm. The thermal stability test of these diffusion barriers showed that these barriers sustained the interdiffusion between Cu and Ag up to 620 °C at least for 30 min in either vacuum or flowing He-0.5% H2. This temperature is a 200°C improvement over previously reported values for the self-encapsulated Cu and Ag films. X-ray diffraction spectra showed no formation of any high resistive intermetallic compounds, i.e., Ag3Al, Ag2Al, and AlAg3.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 612: Symposium D – Materials, Technology & Reliability for Advanced Interconnects.. , 2000 , D9.6.1
Copyright
Copyright © Materials Research Society 2000

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

Reference:

1. Alford, T. L., Li, J., Mayer, J.W., and Wang, S.-Q., Thin Solid Films 262, (1995)10.1016/0040-6090(95)06624-1Google Scholar
2. Alford, T. L., Adams, D., Laursen, T., and Manfred, B. Ullrich, Appl. Phys. Lett. 68, 23 (1996).Google Scholar
3. CRC Handbook of Electrical Resistivities of Binary Metallic Alloys, edited by Shröder, Klaus (CRC, Boca Raton, FL, 1983), p.44.Google Scholar
4. Gutmann, R. J., Kaloueros, A. E., and Lanford, W. A., Thin Solid Films 236, 257 (1993).Google Scholar
5. Lanford, W. A., Ding, P. J., Wang, W., Hymes, S., and Murarka, S. P., Thin Solid Films 262, 234 (1995).10.1016/0040-6090(95)05837-0Google Scholar
6. Wang, W., Lanford, W. L., and Murarka, S. P., Appl. Phys. Lett. 68, 12 (1996).Google Scholar
7. Ding, P. J., Wang, W., Lanford, W. A., Hymes, S., and Murarka, S. P., Appl. Phys. Lett. 65, 14 (1994).Google Scholar
8. Ding, P. J., Wang, W., Lanford, W. A., Hymes, S., and Murarka, S. P., J. Appl. Phys. 75, 7 (1994).Google Scholar
9. Shalish, I., Gasser, S. M., Kolawa, E., Nicolet, M.-A., and Ruiz, R. P., Thin Solid Films 289, 166 (1996).10.1016/S0040-6090(96)08919-5Google Scholar
10. Zetterling, C.-M., Östling, M., Wongchotigul, K., Spencer, M. G., Tang, X., Harris, C. I., Nordell, N., and Wong, S. S., J. Appl. Phys. 82, 2990 (1997).10.1063/1.366136Google Scholar
11. Schroder, D. K., Semiconductor Material and Device Characterization, (Wiley, New York, 1990), P9.Google Scholar
12. Doolittle, L. R., Nucl. Inst. Meth. Res. B9, 344 (1985).10.1016/0168-583X(85)90762-1Google Scholar
13. Lange's Handbook of Chemistry, No. 14, 11th ed, edited by Dean, J. A. (McGraw-Hill, New York, 1992) P6–69.Google Scholar
14. Adams, D., Ph. D. Dissertation, Arizona State University, 1996 Google Scholar
15. Landolt Börnstein New Serie IV/5a, (Springer-Verlag, Berlin, New York, 1961) p5.Google Scholar
16. Tu, K.-N., Mayer, James W., and Feldman, L. C., Electronic Thin Film Science for Electrical Engineers and Materials Scientists, (Macmillan Publishing Company, New York, 1992).Google Scholar
17. Russell, S. W., Alford, T. L., and Mayer, J. W., J. Electrochem. Soc. 142, 1308 (1995).10.1149/1.2044169Google Scholar