Patent ID: 8709838

Claim:
A method for preparing a β-SiAlON phosphor, the method comprising: weighing starting materials in order to prepare the β-SiAlON phosphor represented by Formula: Si (6-x) Al x O y N (8-y) :Ln z (wherein Ln is a rare earth element, and the following requirements are satisfied: 0<x≦4.2, 0<y≦4.2 and 0<z≦1.0), mixing the starting materials to prepare a raw material mixture; and firing the raw material mixture in a nitrogen-containing atmospheric gas, wherein the starting materials comprise: a host raw material including a silicon raw material including a metallic silicon and optionally a silicon compound, and at least one aluminum raw material selected from the group consisting of a metallic aluminum and an aluminum compound, wherein at least one of the silicon raw material and the aluminum raw material contains both metal and compound; and at least one activator raw material selected from rare earth elements for activating the host raw material, wherein the method further comprises the step of adjusting a mixture ratio of the metallic silicon to the silicon compound to control the particle size distribution of the β-SiAlON phosphor such that the mixture ratio of the metallic silicon to the silicon compound is greater than 1.