| abstract |
The present invention relates to oxynitride fluorescent substance powder which contains aluminum nitride and alpha-type SiAlON expressed in the following composition formula: Ca x1 Eu x2 Si 12-(y+z) Al (y+z) O z N 16-z (where, x1 is larger than 0 and equal to or smaller than 3.40, x2 is between 0.05 and 0.20, y is between 4.0 and 7.0, and z is between 0 and 1). A light reflectance of a peak wavelength of a fluorescence of the oxynitride fluorescent substance powder of the present invention, which is emitted by being excited by a light with a wavelength of 450nm, is at least 80%. Silicon nitride powder for manufacturing the oxynitride fluorescent substance powder is crystalline silicon nitride powder with an oxygen content of between 0.2 wt% and 0.9 wt%. A method for manufacturing the oxynitride fluorescent substance powder of the present invention comprises a first process in which a burned oxynitride product expressed in the formula is obtained through source material mixing and burning within a temperature range of between 1,500°C and 2,000°C in an inert gas atmosphere, and a second process in which a thermal treatment is performed on the burned oxynitride product within a temperature range of between 1,100°C and 1,600°C in the inert gas atmosphere. |