Fluorescent Properties of Tb-Doped Borosilicate Glass Films Prepared by a Sol-Gel Method

摘要

Rare-earth elements have been used as optical dopants in glasses for many years. Boro-silicate glass films doped with rare-earths were deposited on glass substrates by using a simple sol-gel method. To avoid the undesirable precipitation due to the different hydrolysis rates between silicon and boron alkoxides, two solutions were used for dip-coating separately. One solution consisted of silicon tetraethoxide, ethanol, water and terbium nitrate as the Tb dopant. Another consisted of triethyl borate. Layer-by-layer deposition was applied by dipping into solutions containing metal alkoxides in sequence. The fluorescent properties of Tb~(3+) were investigated for the boro-silicate samples in relation to the firing effect. As-deposited silicate and boro-silicate samples showed similar fluorescence spectra under UV excitation. After firings at about 800鳦, a remarkable increase of the Tb~(3+)-ion fluorescence was observed for the boro-silicate samples, while the silicate sample showed a little increase in fluorescence intensity. These experimental results suggested the formation of boro-silicate network and the incorporation of Tb~(3+) into the boro-silicate matrix. The multilayer process was found useful to fabricate multi-component sol-gel films.