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Microstructure Control for Thin Film Metallization

Published online by Cambridge University Press:  10 February 2011

G. S. Was ,
D. J. Srolovitz ,
Z. Ma  and
D. Liang
G. S. Was
Affiliation:
Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109
D. J. Srolovitz
Affiliation:
Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109
Z. Ma
Affiliation:
Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109
D. Liang
Affiliation:
Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109
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Abstract

A strategy was developed for controlling hillock formation in thin metal films by controlling the fiber texture to be of a relatively “weak” orientation. Two-dimensional molecular dynamics (MD) simulations were performed to determine the parameter dependencies of texturing under ion beam assisted deposition. Simulations showed that even for film orientations that have a lower number of nearest neighbor surface bonds, the reduction in sputtering rate by ion channeling will favor the growth of the grains aligned with their channeling direction in the direction of the ion beam. Higher energies should result in greater sputtering and a higher surface roughness. Confirmatory experiments were performed by growing Al films using ion beam assisted deposition in which the Ne ion beam was normal to the substrate surface. For all energies above 0 eV/atom, the fiber texture contained a (220) component and, at high normalized energies, the fiber texture was heavily (220) dominated. Subsequent annealing at 450°C for 30 min. resulted in hillock formation in the PVD (physical vapor deposition) condition, a reduction in the hillock density by two orders of magnitude in the 120 eV/atom condition and complete elimination of hillocking above 800 eV/atom. Although the surface roughness increased with ion beam energy as modeled by MD, the surface became smoother during annealing. These results show that the fiber texture can be controlled in a thin metal film in such a way as to eliminate hillock formation, that molecular dynamics simulation is a valuable predictive tool for guiding experiments in the development of thin film microstructures and that ion beam assisted deposition is an effective, practical tool for controlling microstructures of thin metal films.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 441: Thin Films – Structure and Morphology , 1996 , 311
Copyright
Copyright © Materials Research Society 1997

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References

1. Ericson, F., Kristensen, N. and Schweitz, J., J. Vac. Sci. Technol. B 9, 58 (1991).Google Scholar
2. Srolovitz, D.J., Yang, W., Goldiner, M.G., Mater. Res. Soc. Proc. 403, in press.Google Scholar
3. Kim, J. Y. and Hummel, R. E., Phys. stat. sol. (a) 122, 255 (1990).Google Scholar
4. Pennebaker, W. B., J. Appl. Phys. 40, 394 (1969).Google Scholar
5. Lahiri, S. K. and Wells, O. C., J. Appl. Phys. 46, 2791 (1975).Google Scholar
6. Murakami, M., and Kuan, T. S., Thin Solid Films 66, 381 (1980).Google Scholar
7. Dell'oca, C. J. and Learn, A. J., Thin Solid Films 8, R47 (1971).Google Scholar
8. d'Heurle, F., Berenbaum, L. and Rosenberg, R., Trans. Metall. Soc AIME. 242, 502 (1968).Google Scholar
9. Sato, N., Oi, T., Matsumaru, H., Okubo, T. and Nishimura, T., Metall. Trans. 2, 691 (1971).Google Scholar
10. L Mattson, Page, Y.-H.Le and Ericson, F., Thin Solid Films 198, 149 (1991).Google Scholar
11. Sharma, S. K. and Spitz, J., Thin Solid Films 65, 339 (1980).Google Scholar
12. Huang, H.-C., Chaudhari, P., Kircher, C. and Murakami, M., Phil. Mag. A 54, 583 (1986).Google Scholar
13. Génin, F. Y., Acta metall. mater 43 4289 (1995).Google Scholar
14. Sanchez, J. E. and Arzt, E., Scripta Metall. Mat. 27, 285 (1992).Google Scholar
15. Smith, R. W. and Srolovitz, D. J., J.Appl.Phys. 79, 1448 (1996).Google Scholar
16. Moliére, G., Naturforsch, Z. A 2, 133 (1947).Google Scholar
17. Beeler, J. R., Jr.Radiation Effects Computer Experiments (North Holland, New York, 1983).Google Scholar
18. Ying, F., Smith, R. W. and Srolovitz, D. J., Appl. Phys. Letters, 61, in press.Google Scholar
19. Sigmund, P., Phys. Rev. 184 383 (1969).Google Scholar
20. Erck, R. A. and Fenske, G. R., Thin Solid Films 181, 521 (1989).Google Scholar
21. Muller, K. H., Phys. Rev. B 35, 7906 (1987).Google Scholar
22. Stoney, G. G., Proc. Roy. Soc. London A82, 172 (1909).Google Scholar
23. Was, G. S., Jones, J. W., Parfitt, L., Kalnas, C. E. and Goldiner, M., in Ion Solid Interactions for Materials Modification and Processing, edited by Poker, D. B., D., Ila, Y-T., Cheng, Harriott, L. R. and Sigmon, T. W., (Mater. Res. Soc. Proc. 396, Pittsburgh, PA 1996), p. 479–489.Google Scholar
24. Andersen, H. H. and Bay, H. L., in Sputtering by Particle Bombardment I, vol.47 of Topics in Applied Physics, edited by R., Behrisch (Springer, Berlin, 1981).Google Scholar