Journal of Sol-Gel Science and Technology

, Volume 8, Issue 1–3, pp 243–248 | Cite as

Influence of solvent concentration on the microstructure of SiO2−TiO2 sol-gel films

  • Xavier Orignac
  • H. C. Vasconcelos
  • X. M. Du
  • R. M. Almeida


Spin-coating is one of the possible methodsfor the fabrication of optical planar waveguides. These have several applications in integrated optical devices, provided that their optical losses are below ≈1 dB/cm. The attenuation is caused in part by surface and bulk scattering. The latter depends on the microstructure of the films and, more particularly, the porosity, which is studied here. A series of SiO2−TiO2 films were prepared from solutions containing different concentrations of ethanol. The influence of the ethanol/(Si+Ti)alkoxides volume ratio on the porosity was investigated by Ellipsometry, Infrared Spectroscopy, and Scanning Electron Microscopy. The porosity volume fraction was found to reach a minimum when the ethanol volume ratio is near 4.


ethanol porosity scattering sol-gel films waveguides 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    H. Schroeder, inPhysics of Thin Films: Advance in Research and Development, edited by G. Hass and R. E. Thun (Academic Press, New York, 1969) Vol. 5, p. 119.Google Scholar
  2. 2.
    C.J. Brinker and M.S. Harrington, Solar Energy Materials5, 159–172 (1981).CrossRefGoogle Scholar
  3. 3.
    H. Dislich and E. Hussmann. Thin Solid Films.77, 129–139 (1981).CrossRefGoogle Scholar
  4. 4.
    R.M. Almeida, X. Orignac, and D. Barbier, Journal of Sol-Gel Science and Technology2, 465–467 (1994).CrossRefGoogle Scholar
  5. 5.
    D. Barbier, X. Orignac, X.M. Du, and R.M. Almeida, inAdvanced Materials in Optics, Electro-Optics and Communication Technologies, edited by P. Vincenzini and G.C. Righini (Techna, Faenza, 1995), p. 33.Google Scholar
  6. 6.
    K. Arai, H. Namikawa, K. Kumata, T. Honda, Y. Ishii, and T. Handa, J. of Applied Physics59, 3430–3436 (1986).CrossRefGoogle Scholar
  7. 7.
    K. Arai, H. Namikawa, Y. Ishii, H. Hosono, and Y. Abe, J. of Non-Crystalline Solids95&96 609–616 (1987).CrossRefGoogle Scholar
  8. 8.
    X. Orignac, X.M. Du, D. Barbier, and R.M. Almeida, submitted to Electronics Letters.Google Scholar
  9. 9.
    C.J. Brinker and G.W. Scherer,Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing (Academic Press, San Diego, 1990) p. 108.Google Scholar
  10. 10.
    E.M. Yeatman, M. Green, E.J.C. Dawnay, M.A. Fardad, and F. Horowitz, Journal of Sol-Gel Science and Technology2, 711–715 (1994).CrossRefGoogle Scholar
  11. 11.
    X. Orignac, unpublished results.Google Scholar
  12. 12.
    R.M. Almeida and H.C. Vasconcelos, SPIE2288, 678–687 (1994).Google Scholar
  13. 13.
    M. Born and E. Wolf.Principles of Optics (Pergamon Press, Oxford, 1980), p. 87.Google Scholar
  14. 14.
    X. Orignac, H.C. Vasconcelos, and R.M. Almeida, unpublished results.Google Scholar
  15. 15.
    R.M. Almeida, International Journal of Optoelectronics9, 135–142 (1994).Google Scholar

Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Xavier Orignac
    • 1
  • H. C. Vasconcelos
    • 1
  • X. M. Du
    • 1
  • R. M. Almeida
    • 1
  1. 1.Instituto de Engenharia de Sistemas e ComputadoresLisboaPortugal

Personalised recommendations