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Stress and Microstructure in Lpcvd Polycrystalline Silicon Films: Experimental Results and Closed Form Modeling of Stresses

Published online by Cambridge University Press:  22 February 2011

P. Krulevitch ,
G. C. Johnson  and
R. T. Howe
P. Krulevitch
Affiliation:
Berkeley Sensor & Actuator Center, Department of Mechanical Engineering, and Computer Sciences, University of California, Berkeley, CA 94720
G. C. Johnson
Affiliation:
Berkeley Sensor & Actuator Center, Department of Mechanical Engineering, and Computer Sciences, University of California, Berkeley, CA 94720
R. T. Howe
Affiliation:
Berkeley Sensor & Actuator Center, Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA 94720
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Abstract

Characterization of undoped polycrystalline silicon films indicates that correlations exist between stress and microstructure. Films of thickness between 0.5–3.6 μm were deposited onto SiO2-covered single crystal silicon wafers between 605 and 700°C using low pressure chemical vapor deposition (LPCVD). The average in-plane film stress and the stress gradient through the film thickness were determined from wafer curvature measurements, and film microstructure was studied with cross-sectional TEM. Films deposited near 605°C exhibit overall tensile stresses that result from an amorphous to crystalline phase change. At deposition temperatures exceeding 630°C, a columnar grain structure evolves out of a transition region of small grains at the SiO2 interface. The columnar films are compressive, with the source of compression linked to the region of small grains. Stress is modeled using a closed form solution ihat considers a linearly elastic contracting ellipsoidal inclusion near the surface of a half space. Several applications of the stress model are discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 239: Symposium D – Thin Films: Stresses and Mechanical Properties III , 1991 , 13
Copyright
Copyright © Materials Research Society 1992

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References

REFERENCES

1. Prall, R.I., Johnson, G.C., and Howe, R.T., “Micromechanical Structures for Thin Film Characterization,” Digest of Technical Papers, Transducers '91, San Francisco, CA, p. 205, June, 1991.Google Scholar
2. Ried, Bob, private communication.Google Scholar
3. Seo, K. and Mura, T., “The Elastic Field in a Half Space Due to Ellipsoidal Inclusions With Unifonn Dilatational Eigenstrains,” J. Appl. Mech., vol. 46, p. 568, 1979.Google Scholar
4. Huang, J., Krulevitch, P., Johnson, G.C., Howe, R.T., and Wenk, H.R., “Investigation of Texture and Stress in Undoped Polysilicon Films,” Mai. Res. Soc. Symp. Proc., vol. 182, p. 201, 1990.CrossRefGoogle Scholar
5. Krulevitch, P., Howe, R.T., Johnson, G.C., and Huang, J., “Stress in Undoped LPCVD Polycrystalline Silicon,” Digest of Technical Papers, Transducers '91, San Francisco, CA, p. 949, June, 1991.Google Scholar
6. Stoney, G.G., “The Tension of Metallic Films Deposited by Electrolysis,” Proc. Roy. Soc. London, vol. 9, p. 172, 1909.Google Scholar
7. Nguyen, Tai D., Grónsky, R., and Kortrighl, J.B., “Cross-sectional Transmission Electron Microscopy of Multilayer Thin Film Structures,” (submitted to Journal of electron Microscopy Techniques), 1990.Google Scholar
8. Magarino, J., Kaplan, D., Bisaro, R., Morhange, J.F., and Zclma, K., “Structural and Electronic Properties of CVD Silicon Films Near the Crystallization Temperature,” Journal de Physique, vol. 43, pp. cl–271, 1982.Google Scholar
9. Kinsbron, E., Sternheim, M., and Knocił, R., “Crystallization of Amorphous Silicon Films During Low Pressure Chemical Vapor Deposition,” Appl. Phys. Lett., vol. 42. p. 835, 1983.CrossRefGoogle Scholar
10. Bloem, J. and Beers, A.M., “In Situ Observations on Amorphous Versus Crystalline Growth of Silicon by Chemical Vapor Deposition,” Thin Solid Films, vol. 124, p. 93, 1985.CrossRefGoogle Scholar
11. Guckcl, H., Bums, D.W., Visser, C.C.G., Tilmans, H.A.C., and DcRoo, D., “Fine-Grained Polysilicon Films with Built-in tensile Strain,” IEEE Trans. Electron Devices, vol. ED–35, p. 800, 1988.Google Scholar
12. Howe, R.T. and Muller, R.S., “Stress in Polycrystalline and Amorphous Silicon Thin Films,” J. Appl. Phys., vol. 54, p. 4674, 1983.CrossRefGoogle Scholar
13. Mindlin, R.D. and Cheng, D.H., “Thcrmoclastic Stress in the Semi-Infinite Solid,” J.Appl. Phys., Vol. 21, p. 931, 1950.CrossRefGoogle Scholar
14. Janai, M., Allrcd, D.D., Booth, D.C., and Séraphin, B.O., “Optical Properties and Structure of Amorphous Silicon Films Prepared by CV D,” Solar Energy Materials, vol. 1, p. 11. 1979.Google Scholar
15. Eshelby, J.D., “The Determination of the Elastic Field of an Ellipsoidal Inclusion, and Related Problems,” Proceedings of the Royal Society, London, vol. A, No. 241, p. 376, 1957.Google Scholar
16. Krulevitch, P., Nguyen, Tai D., Johnson, G.C., Howe, R.T., Wenk, H.R., and Grónsky, R., “LPCVD Polycrystalline Silicon Thin Films: The Evolution of Structure, Texture, and Stress,” Mat. Res. Soc. Symp. Proc, vol. 202, p. 167, 1990.Google Scholar
17. van der Drift, A., “Evolutionary Selection, A Principle Governing Growth Orientation in Vapour-Deposited Layers,” Philips Res. Repls., vol. 22, p. 267, 1967.Google Scholar
18. d'Heurle, F.M. and Harper, J.M.E., “Note on the Origin of Intrinsic Stresses in Films Deposited Via Evaporation and Sputtering,” Thin Solid Films, vol. 171, p. 81, 1989.Google Scholar
19. Brodsky, M.H., Kaplan, D., and Ziegler, J.F., “Densities of Amorphous Si Films by Nuclear Backscattcring,” Appl. Phys. Lett., vol. 21, p. 305, 1972.Google Scholar
20. Lapiccirclla, A., Tomassini, N., Lodge, K.W., and Allmann, S.L., “Force Field Treatment of an Amorphous Silicon Model,” Journal of Non-Crystalline Solids, vol. 63, p. 301, 1984.CrossRefGoogle Scholar
21. Suzuki, T., Mimura, A., and Ogawa, T., “The Deformation of Polycrystalline Silicon Deposited on Oxide-Covered Single Crystal Silicon Substrates,” J. Eleclrochem. Soc, vol. 124, p. 1776, 1977.Google Scholar