Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-27T02:08:31.816Z Has data issue: false hasContentIssue false
  • English
  • Français

Crack formation due to annealing of Al2O3 films grown on Si(100) by MOCVD

Published online by Cambridge University Press:  11 February 2011

M. P. Singh  and
S.A. Shivashankar
M. P. Singh
Affiliation:
Materials Research Centre, Indian Institute of Science, Bangalore –560 012, India, Email: [email protected], [email protected]
S.A. Shivashankar
Affiliation:
Materials Research Centre, Indian Institute of Science, Bangalore –560 012, India, Email: [email protected], [email protected]
Get access

Abstract

We report crack formation in alumina films grown on Si(100), caused by annealing in a controlled oxidizing ambient. The films were grown in a low-pressure CVD reactor, using aluminium acetylacetonate as precursor. High purity argon and nitrous oxide were employed as carrier and oxidizing gas, respectively. The films were characterized by optical microscopy and SEM/EDAX. The proportion and chemical nature of the heteroatoms, namely C and H, incorporated into the films from the precursor, were characterized by XPS, and FTIR. As-deposited films do not exhibit any cracks, while post-deposition annealing results in cracks. Apart from the delamination of the films, annealing in nitrous oxide ambient leads to an unusual crack geometry, which we term the “railway-track”. These twin cracks are very straight and run parallel to each other for as much as several millimeters. Often, two such linear tracks meet at exactly 90°. Between some of these tracks lie bullet-like structures with very sharp tips, oriented in a specific direction. As cracks are generally activated by residual stress, both thermal and intrinsic, the origins of the stresses that generate these linear cracks are discussed. The redistribution of stress, arising from the removal of C and H during annealing, will also be discussed. An attempt has been made to correlate the formation of cracks with the crystal structure of the film.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 749: Symposium W – Morphological and Compositional Evolution of Thin Films , 2002 , W12.4
Copyright
Copyright © Materials Research Society 2003

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. Hong, S., Weihs, T. P., Bravman, J. C., and Nix, W. D. in Thin Films: Stresses and Mechanical Properties, edited by Bravman, J.C., Nix, W.D., Barnet, D. M., and Smith, D.A. (Mater. Res. Soc. Symp. Proc. 130, Pittsburgh, PA, 1989) pp.93–98.Google Scholar
2. Haanappel, V.A.C., van Corbach, H. D., Fransen, T., and Gellings, P.J., Mater. Sci. Eng. A167, 179 (1993).Google Scholar
3. Haanappel, V.A.C., van Corbach, H. D., Fransen, T., and Gellings, P.J., Surf. Coat. Tech. 64, 183 (1994).Google Scholar
4. Evans, A. G. and Hutchinson, J.W., Acta. Mettal. Mater 43, 2507 (1995).Google Scholar
5. Gille, G., In Current Topics in Materials Science, edited by Kaldis, E., 12 (1985, North Holland-Amsterdam).Google Scholar
6. Ye, T., Suo, Z., and Evans, A.G., Int. J. Solids Structures 29, 2639 (1992).Google Scholar
7. Doerner, M.F. and Nix, W.D., CRC Crit. Rev. Solid States Mater. Sci. 14, 224(1988).Google Scholar
8. Singh, M. P., Shripathi, T., and Shivashankar, S.A., Communicated to European Chemical Vapour Deposition (EUROCVD) Conference 14, Paris, France, 2003.Google Scholar
9. Singh, M. P., Shivashankar, S. A., and Shripathi, T., Int. J. Mod. Phys. B16, 1261 (2002).Google Scholar
10. Maruyama, T. and Arai, S., Appl. Phys. Lett. 60, 24(1992).Google Scholar