Luminescence properties of (Ca,Y)-α-SiAlON:Eu phosphors

(Ca,Y)-α-SiAlON:Eu phosphors for white LED lamps were prepared and their luminescence properties were investigated. A red shift of emission wavelength occurred when Ca was partially replaced by Y. Raising the sintering temperature also caused the red shift. As a result, the peak emission wavelength varied from 585 nm to 608 nm, with increasing of the Y content and the sintering temperature, and therefore the chromaticity range of (Ca,Y)-α-SiAlON phosphors extended to longer wavelength by these results. The corresponding correlated color temperature (CCT) of white LED lamps using (Ca,Y)-α-SiAlON:Eu also extended to the temperature as low as 1700 K.