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Properties of Sputtered Bilayer WNx/W Diffusion Barriers between Si and Cu

Published online by Cambridge University Press:  17 March 2011

K. D. Leedy ,
M. J. O'Keefe ,
E. J. Dahlgren  and
J. T. Grant
K. D. Leedy
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, OH 45433
M. J. O'Keefe
Affiliation:
University of Missouri-Rolla, Dept. of Metallurgical Engineering, Rolla, MO 65401
E. J. Dahlgren
Affiliation:
University of Missouri-Rolla, Dept. of Metallurgical Engineering, Rolla, MO 65401
J. T. Grant
Affiliation:
Research Institute, University of Dayton, Dayton, OH 45469
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Abstract

Copper interconnect metallizations in next generation integrated circuits will require thin diffusion barrier layers (<20 nm) between the Cu and low-k dielectric which may also function as seed layers for subsequent material depositions. One possible structure entails a multicomponent diffusion barrier with a lower resistivity component, such as W on WNx. In this study, sputtered WNx/W bilayer thin films were investigated as diffusion barriers between Si and Cu. The total thickness of the WNx/W bilayer was fixed at 20 nm while the WNx thickness was varied from 0 to 20 nm. After deposition of the barrier films, a 100 nm thick Cu film was sputtered over the top of the á-W and amorphous WNx bilayer. The as-deposited WNx/W film stress was found to be strongly dependent on the relative amount of WNx and W present and the addition of a Cu overlayer was found to mitigate the stress levels. The WNx/W barriers remained stable after 650°C anneals and exhibited phase transformations to W2N. Microstructural characterization using transmission electron microscopy and x-ray diffraction and chemical analysis by x-ray photoelectron spectroscopy of the films were used to identify the as-deposited and transformed phases.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 714: Symposium – Materials, Technology and Reliability for Advanced Interconnects and Low-k Dielectrics II , 2001 , L4.6.1
Copyright
Copyright © Materials Research Society 2001

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References

REFERENCES

1. Galewski, C. and Seidel, T., European Semiconductor Design Production Assembly 21(1), 31 (1999).Google Scholar
2. Wong, S. S., Ryu, C., Lee, H. and Kwon, K.-W. in Advanced Interconnects and Contact Materials and Processes for Future Integrated Circuits, edited by Murarka, S. P., Fraser, D. B., Eizenberg, M., Tung, R., Madar, R. (Mater. Res. Soc. Proc. 514, Warrendale, PA, 1998) pp. 75–81.Google Scholar
3. Chin, B. et al. , Solid State Technol. 41(7), 141 (1998).Google Scholar
4. Sun, X., Kolawa, E., Chen, J.-S., Reid, J. S. and Nicolet, M.-A., Thin Solid Films 236, 347 (1993).Google Scholar
5. Uekubo, M., Oku, T., Nii, K., Murakami, M., Takahiro, K., Yamaguchi, S., Nakano, T. and Ohta, T., Thin Solid Films 286, 170 (1996).Google Scholar
6. Lee, C. W. and Kim, Y. T., Appl. Phys. Lett. 65(8), 965 (1994).Google Scholar
7. Lin, J., Tsukune, A., Suzuki, T. and Yamada, M., Vac, J.. Sci. Technol. A 17(3), 936 (1999).Google Scholar
8. Lee, C. W., Kim, Y. T., Lee, C., Lee, J. Y., Min, S.-K. and Park, Y. W., Vac, J.. Sci. Technol. B 12(1), 69 (1994).Google Scholar
9. Ono, H., Nakano, T. and Ohta, T., Appl. Phys. Lett. 64(12), 1511 (1994).Google Scholar
10. Pokela, P. J., Kwok, C.-K., Kowala, E., Raud, S. and Nicolet, M.-A., Appl. Surface Science 53, 364 (1991).Google Scholar
11. Suh, B.-S., Lee, Y.-J., Hwang, J.-S. and Park, C.-O., Thin Solid Films 348, 299 (1999).Google Scholar
12. So, F. C. T., Kolawa, E., Zhao, X.-A., Pan, E. T.-S. and Nicolet, M.-A., J. Appl. Phys. 64(5), 2787 (1988).Google Scholar
13. Ganguli, S., Chen, L., Levine, T., Zheng, B. and Chang, M., J. Vac. Sci. Technol. B 18(1), 237 (2000).Google Scholar
14. Yongjun, H., U. S. Patent No. 5633200, 1997.Google Scholar
15. Leedy, K. D., O'Keefe, M. J., Wilson, J. G., Osterday, R., and Grant, J. T. in Materials, Technology and Reliability for Advanced Interconnects and Low-k Dielectrics, edited by Maex, K., Joo, Y-C., Oehrlein, G.S., Ogawa, S. and Wetzel, J.T. (Mater. Res. Soc. Proc. 612, Warrendale, PA, 2001) in press.Google Scholar
16. Shen, Y. G. and Mai, Y. W., Surface and Coatings Technol. 127, 239 (2000).Google Scholar
17. Kelsey, J. E., Goldberg, C., Nuesca, G., Peterson, G. and Kaloyeros, A. E., J. Vac. Sci. Technol. B 17(3), 1101 (1999).Google Scholar
18. Yu, K. M., Jaklevic, J. M., Haller, E. E., Cheung, S. K. and Kwok, S. P., J. Appl. Phys. 64(3), 1284 (1988).Google Scholar
19. Grant, J. T. in Methods in Materials Research, edited by Kaufmann, E.N., (John Wiley & Sons), 11d.2, pp.1–19 (2000).Google Scholar
20. Lin, J., Tsukune, A., Suzuki, T. and Yamada, M., J. Vac. Sci. Technol. A 16(2), 611 (1998).Google Scholar