Field-assisted ion diffusion in dielectric matrices: Er3+ in silicate glass

The ion exchange process is used in several materials application fields for introducing high dopant doses into glass. In this frame, field-assisted techniques are particularly interesting, allowing the penetration of multivalent ions which could not diffuse into the glass matrix by simple thermal treatments. In the presented experiments, field-assisted ion diffusion of erbium in silicate glasses was performed for the first time, with the aim to define suitable methodologies for the controlled Er doping of glasses, with application in the field of rare earth-doped photonic materials for light amplification. Metallic erbium films deposited onto the substrates by the rf-sputtering technique were used as the metal ions source. Secondary ion mass spectrometry shows a partial diffusion of erbium into the glass matrix, depending on the electric field and the process temperature values, and a corresponding migration of alkaline species already present in the glass. Photoluminescence emission at 1.54 μm was also determined in the samples.