Barium and lithium silicate glass ceramics doped with rare earth ions for white LEDs

Novel glasses and glass ceramics with compositions corresponding to stoichiometric lithium and barium disilicates and doped with different combinations of Ce3+, Eu2+,3+, Tb3+, and Dy3+ have been fabricated and studied as prospective light converters for white high-power light emitting diodes and laser diodes. Spatially resolved photoluminescence spectroscopy and structural analysis have been employed. The emission spectra and CIE color coordinates of these materials evidence their good prospective as phosphors for white light sources. Structural analysis proves a high level of crystallization of the ceramics fabricated by annealing the glasses, while spectroscopic study revealed the influence of crystallization on the emission properties of this system. The results show a high potential of these materials be exploited as temperature-resistant phosphors in high-power white light emitting diodes.