Fabrication of glasses of dispersed yellow oxynitride phosphor for white light-emitting diodes

Ca–α–SiAlON:Eu2+ is known to be a typical oxynitride phosphor for luminescent materials. We investigated the potential as white LEDs of various glasses into which Ca–α–SiAlON:Eu2+ phosphor was dispersed. Borate and tellurite glasses were melted at 1200 °C using a combinatorial melting system. Several glasses, 2R2O–50ZnO–48B2O3 (mol%; R = Li, Na, K), 30Na2O−10ZnO−60TeO2 and 20Na2O−30ZnO−50TeO2, were dispersed homogeneously with SiAlON powders without degradation. The color generated by irradiation of blue LED at 450 nm depended on the concentration of SiAlON and the thickness of the glasses, resulting in nearly white light in some cases.