Evaluation of YAG:Ce³⁺ Phosphor Properties Synthesized by Mechanical Method

Abstract

In this study, the properties of Ce³⁺-doped Y₃Al₅O₁₂ (YAG:Ce³⁺) phosphors for white light emitting diodes by mechanical method was evaluated. The YAG:Ce³⁺ phosphors were synthesized by the mechanical method using an attrition-type mill without any extra-heat assistance. BaF₂, YF₃ and Al(OH)₃ was used as an additive for its lower temperature reaction, respectively. The synthesis of YAG:Ce³⁺ phosphor was favorably achieved after 10–30 min by mechanical processing with the addition of each additive. As a result, it was made clear that the quantum yield of phosphor was well related to the crystallite size of the sample regardless of the kind of additives. The absorption rate of YAG phosphors were also well related to its median diameter. Both relationships almost agreed to those obtained for the YAG:Ce³⁺ phosphors synthesized by solid reaction method. It was suggested that the increase of crystallite size and median size of the sample synthesized by mechanical method is key issue to achieving higher quality of YAG:Ce³⁺ phosphor.