Eu2+ ion-doped oxynitride phosphor, (Sr0.5Ba0.5)Si2O2N2:Eu2+, was prepared by solid-state reaction using metal alloy as precursor. Owing to the relatively high activity of the metal alloy precursor compared with the inert Si3N4, a single phase of solid solution phosphor (Sr0.5Ba0.5)Si2O2N2:Eu2+ was easily obtained at 1400 degrees C under atmospheric pressure. It showed a broad excitation band originating from the 4f(7) -> 4f(6)5d transition of Eu2+ ion, extending to 520 nm, and centering at 460 nm and a strong emission band peaking at 565 nm. The high emission and small thermal quenching allow this material to be used for phosphor-converted white LEDs.