FLUORESCENT SUBSTANCE AND PRODUCTION METHOD THEREOF, AND LIGHT EMITTING DEVICE

摘要

Offered is a fluorescent substance consisting of Eu-activated ²-sialon and capable of enhancing the brightness of a light emitting device such as a white LED using blue or ultraviolet light as a light source. The fluorescent substance has as its main constituent a ²-sialon represented by the general formula Si 6-z Al z O z N 8-z and containing Eu, wherein the spin density is 2.0 × 10 17 /g or less as measured by electron spin resonance spectroscopy corresponding to an absorption of g = 2.00 ± 0.02 at 25 °C. In the above fluorescent substance, it is preferable that lattice constant a of the ²-sialon be 0.7608-0.7620 nm, the lattice constant c be 0.2908-0.2920 nm, and the Eu content be 0.1-3 mass%.