Part of the NATO Science Series book series (NAII, volume 2)


Doped silica is a key material in several technological fields. Its physical properties can be suitably tuned for obtaining specific features by introducing dopants atoms substituting for silicon in the network. In fiberoptics, doping with germanium atoms permits the creation of the radial profile of refractive index which is essential for an optical guide. Ge and Sn substitutional doping can also induce interesting photochromic features which may be used to write longitudinally modulated refraction index patterns for obtaining filters or for compensating dispersion effects in silica-based optical fibers (Hill gratings [1,2]). It is not yet clear the main role of dopants in these processes. In fact, beyond the introduction of additional electronic levels peculiar of the dopant species, dopants can influence the medium range order of the SiO2 network, also favouring the formation of intrinsic defects (as oxygen vacancies) by changing the thermochemical conditions during the material synthesis [2]. Indeed, Ge and Sn doping cause perturbations in the structural and defect-related properties, and these are important for the occurrence of photoconversion of optically active defects and photoinduced structural densification [2-5]. Nevertheless, the effect of dopant atoms on native structural stresses and coordination defects may also depends on the preparation method. In fact the amorphous silica network cannot be related to a well defined structure, and a continuum of possible structures may be compatible with the same stoichiometry but differentiated as medium range coordination features. Defect occurrence and defect properties may in turn be affected by structural modifications. As a result, different situations may be experimentally found in nominally identical materials owing to variations in the topological properties of the matrix. For this reason, in the physics of SiO2 defects careful attention is to be paid in the synthesis parameters. Doping itself, no matter which atomic species are involved, should be sought as a perturbation of the structure, able to induce a change of average structural features in the silica network. For these reason, before


Electron Paramagnetic Resonance Electron Paramagnetic Resonance Spectrum Electron Paramagnetic Resonance Signal Dope Silica Radiation Induce Centre 
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  1. 1.
    Hill, K.O., Fujii, Y., Johnson, D.C. and Kawasaky, B.S. (1978) Photosensitivity in optical fiber waveguides: application to reflection filter fabrication, Appl Phys. Lett. 32, 647–649.CrossRefGoogle Scholar
  2. 2.
    Poumellec, B. and Kherbouche, F. (1996) The photorefractive Bragg gratings in the fibers for telecommunications, J. Phys. III France 6, 1595–1624.CrossRefGoogle Scholar
  3. 3.
    Hosono, H., Kawamura, K., Ueda, N., Kawazoe, H., Fujitsu, S. and Matsunami, N. (1995) Formation and photobleaching of 5 eV bands in ion-implanted SiO2:Ge and SiO2 glasses for photosensitive materials, J. Phys.: Condens. Matter 7, L343–L350.CrossRefGoogle Scholar
  4. 4.
    Crivelli, B., Martini, M., Meinardi, F., Paleari, A. and Spinolo, G. (1996) Photoinduced conversion of optically active defects in germanium-doped silica, Phys. Rev. B 54, 16637–16640.CrossRefGoogle Scholar
  5. 5.
    Tsai, T.E., Askins, C.G. and Friebele, E.J. (1992) Photoinduced grating and intensity dependence of defect generation in Ge-doped silica optical fiber, Appl. Phys. Lett. 61, 390–392.CrossRefGoogle Scholar
  6. 6.
    Sharma, S.K., Matson, D.W., Philpotts, J.A. and Roush, T.L. (1984) Raman study of the structure of glasses along the join SiO2-GeO2, J. Non-Cryst. Sol 68, 99–114.CrossRefGoogle Scholar
  7. 7.
    Mukherjee, S.P. and Sharma, S.K. (1985) A comparative Raman study of the structures of conventional and gel-derived glasses in the SiO2-GeO2 system, J. Non-Cryst. Sol. 71,317–325.CrossRefGoogle Scholar
  8. 8.
    Bogdanov, V.N., Brovchenko, I.M., Maksimov, L.V., Silin, A.R. and Yanush, O.V. (1990) Spectroscopic, optical, and acoustic investigations of radiation modified silica glasses, Phys. Stat. Sol. (a) 119, 621–629.CrossRefGoogle Scholar
  9. 9.
    Bertoluzza, A., Fagnano, C, Morelli, M.A., Guglielmi, M., Scarinci, G. and Maliavski, N. (1988) Raman spectra of SiO2 gel glasses prepared from alkoxide, colloidal and amine silicate solutions, J. Raman Spectroscopy 19, 297–300.CrossRefGoogle Scholar
  10. 10.
    Geissberger, A.E. and Galeener, F.L. (1983) Raman studies of vitreous SiO2 versus fictive temeperature, Phys. Rev. B 28, 3266–3271.CrossRefGoogle Scholar
  11. 11.
    Warren, W.L., Lenahan, P.M. and Brinker, C.J. (1991) Relationship between strained silicon-oxygen bonds and radiation induced paramagnetic point defects in silicon dioxide, Sol St. Commun. 79, 137–141.CrossRefGoogle Scholar
  12. 12.
    Chiodini, N., Meinardi, F., Morazzoni, F., Paleari, A., Scotti, R. and Spinolo, G. (1999) Tin doped silica by sol-gel method: doping effects on the SiO2 Raman spectrum, Sol St. Commun. 109, 145–150.CrossRefGoogle Scholar
  13. 13.
    Galeener, F.L. (1978) Band limits and the vibrational spectra of tetrahedral glasses, Phys. Rev. B 19, 4292–4297.CrossRefGoogle Scholar
  14. 14.
    Murray, R.A. and Ching, W.Y. (1989) Electronic-and vibrational-structure calculations in models of the compressed SiO2 glass system, Phys. Rev. B 39, 1320–1331.CrossRefGoogle Scholar
  15. 15.
    Sharma, S.K., Mammone, J.F. and Nicol, M.F. (1981) Raman investigation of ring configurations in vitreous silica, Nature 292, 140–141.CrossRefGoogle Scholar
  16. 16.
    Galeener, F.L. (1982) Planar rings in glasses, Sol St. Commun. 44, 1037–1040.CrossRefGoogle Scholar
  17. 17.
    Pasquarello, A. and Car, R. (1998) Identification of Raman defect lines as signatures of ring structures in vitreous silica, Phys. Rev. Lett. 80, 5145–5147.CrossRefGoogle Scholar
  18. 18.
    Murray, C.A. and Greytak, T.J. (1979) Intrinsic surface phonons in amorphous silica, Phys. Rev. B 20,3368–3387.CrossRefGoogle Scholar
  19. 19.
    Gottardi, V., Guglielmi, M., Bertoluzza, A., Fagnano, C. and Morelli, M.A. (1984) Further investigations on Raman spectra of silica gel evolving towards glass, J. Non-Cryst. Sol 63, 71–80.CrossRefGoogle Scholar
  20. 20.
    Matson, D.W., Sharma, K. and Philpotts, J.A. (1983) The structure of high-silica alkali-silicate glasses. A Raman spectroscopic investigation, J. Non-Cryst. Sol. 58, 323–352.CrossRefGoogle Scholar
  21. 21.
    Stolen, R.H. and Walrafen, G.E. (1976) Water and its relation to broken bond defects in fused silica, J. Chem. Phys. 64, 2623–2631.CrossRefGoogle Scholar
  22. 22.
    Riebling, E.F. (1968) Nonideal mixing in binary GeO2-SiO2 glasses, J. American Ceram. Soc. 51, 406–407.CrossRefGoogle Scholar
  23. 23.
    Tsai, T.E., Friebele, E.J., Rajaram M. and Mukhapadhyay, S. (1994) Structural origin of the 5.16 eV optical absorption band in silica and Ge-doped silica, Appl Phys. Lett. 64, 1481–1483.CrossRefGoogle Scholar
  24. 24.
    Jackson, J.M., Wells, M.E., Kordas, G., Kinser, D.L. and Weeks, R.A. (1985) Preparation effects on the UV optical properties of GeO2 glasses, J. Appl Phys. 58, 2308–2311.CrossRefGoogle Scholar
  25. 25.
    Martini, M., Meinardi, F., Paleari, A., Portinari, L. and Spinolo, G. (1997) Role of impurities in the 5.16 eV optical absorption band of ge-doped silica, J. Non-Cryst. Sol. 216, 26–29.CrossRefGoogle Scholar
  26. 26.
    Griscom, D.L. (1991) Optical properties and structure of defects in silica glass, J. Ceram. Soc. Japan 99, 899–916.CrossRefGoogle Scholar
  27. 27.
    Skuja, L. (1998) Optically active oxygen-deficiency-related centers in amorphous silican dioxide, J. Non-Cryst. Sol 239, 16–48.CrossRefGoogle Scholar
  28. 28.
    Neustruev, V.B. (1994) Colour centres in germanosilicate glass and optical fibres, J. Phys.: Condens. Matter 6, 6901–6936.CrossRefGoogle Scholar
  29. 29.
    Skuja, L. (1992) Isoelectronic series of twofold coordinated Si, Ge, and Sn atoms in glassy SiO2: a luminescence study, J. Non-Cryst. Sol 149, 77–95.CrossRefGoogle Scholar
  30. 30.
    Chiodini, N., Meinardi, F., Morazzoni, F., Paleari, A., Scotti, R. and Di Martino, D. (2000), J. Non-Cryst. Sol 261, 1–8.CrossRefGoogle Scholar
  31. 31.
    Martini, M., Meinardi, F., Paleari, A., Spinolo, G., Vedda, A., Di Martino, D. and Negrisolo, F. (1997) Sn codoping effects on the photoluminescence of SiO2:Ge, Phys. Rev. B 55, 15375–15377.CrossRefGoogle Scholar
  32. 32.
    Chiodini, N., Meinardi, F., Morazzoni, F., Paleari, A., and Scotti, R. (1999) Optical transitions of paramagnetic Ge sites created by x-ray irradiation of oxygen-defect-free Ge-doped SiO2 by the sol-gel method, Phys. Rev. B 60, 2429–2435.CrossRefGoogle Scholar
  33. 33.
    Friebele, E.J., Griscom, D.L., and Siegel Jr., G.H. (1974) Defect centers in a germanium-doped silica-core optical fiber, J. Appl. Phys. 45, 3424–3428.CrossRefGoogle Scholar
  34. 34.
    Neustruev, V.B. (1994) Colour centres in germanosilicate glass and optical fibres, J. Phys.: Condens. Matter 6, 6901–6936.CrossRefGoogle Scholar
  35. 35.
    Chiodini, N., Meinardi, F., Morazzoni, F., Paleari, A., Scotti, R., and Spinolo, G. (1998) Identification of Sn variants of the E’ center in Sn-doped SiO2, Phys. Rev. B 58,9615–9618.CrossRefGoogle Scholar
  36. 36.
    Watanabe, Y., Kawazoe, H., Shibuya, K., and Muta, K. (1986) Structure and mechanism of formation of drawing-or radiation-induced defects in SiO2:GeO2 optical fibers, Jpn. J. Appl. Phys. 25, 425–431.CrossRefGoogle Scholar
  37. 37.
    Kawazoe, H. (1985) Effects of modes of glass formation on structure of intrinsic or photon induced defects centered on III, IV or V cations in oxide glasses, J. Non-Cryst. Sol. 71,231–243.CrossRefGoogle Scholar
  38. 38.
    Anoikin, E.V., Guryanov, A.N., Gusovsky, D.D., Dianov, E.M., Mashinsky, V.M., Miroshnicenko, S.I., Neustruev, V.B., Tikhomirov, V.A., and Zverev, Yu.B. (1992) UV and gamma radiation damage in silica glass and fibres doped with germanium and cerium, Nucl. Instr. Meth. Phys. Res. B65, 392–396.CrossRefGoogle Scholar
  39. 39.
    Mazzeo, C. (1999) thesis, University of Milano.Google Scholar
  40. 40.
    Hosono, H., Mizuguchi, M., Kawazoe, H., and Nishii, J. (1996) Correlation between Ge E’ centers and optical absorption bands in SiO2:GeO2 glasses, Jpn. J. Appl. Phys. 35, L234–L236.CrossRefGoogle Scholar
  41. 41.
    Griscom, D.L. (1984) Characterization of three E’-center variants in X-and β-irradiated high purity a-SiO2, Nucl. Instr. Meth. Phys. Res. Bl, 481–488.CrossRefGoogle Scholar
  42. 42.
    Brunthaler, G., Jantsch, W., Kaufmann, U., and Schneider, J. (1985) Electron-spin-resonance analysis of the deep donors lead, tin, and germanium in CdTe, Phys. Rev. B 31, 1239–1243.CrossRefGoogle Scholar

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© Springer Science+Business Media Dordrecht 2000

Authors and Affiliations

    • 1
  1. 1.Istituto Nazionale Fisica della Materia-Dipartimento di Scienza dei MaterialiUniversità di Milano-BicoccaMilanoItaly

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