Diffusion properties of chalcogens (S, Se, Te) into pure silica

Université Paris-Sud 11, Orsay, Île-de-France, France
Journal of Non-Crystalline Solids (Impact Factor: 1.77). 10/2005; 351(37-39):3031-3036. DOI: 10.1016/j.jnoncrysol.2005.07.011


The diffusion properties of chalcogens (S, Se, Te) implanted into SiO2 were studied via secondary ion mass spectroscopy (SIMS) profiling between room temperature and the glass transition temperature (800–950 °C). Annealing of Te-containing samples leads directly to precipitation of metallic tellurium nanocrystals within the implantation profile. The S and Se concentration profiles were fitted by using a simple diffusion model in order to provide estimates of the diffusion constant and approximate solubility of these fast moving chemical species. A comparison of their differing diffusion behavior with complementary data on these systems suggests that (i) their oxidation states play a crucial role and (ii) the chalcogen propagation mechanism actually involves complex chemical interactions.

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