Spectral dependency of Eu~(2+)-activated silicate phosphors on the composition for LED application

摘要

An Sr_2SiO_4-Ba_2SiO_4 material system doped by Eu~(2+) was studied for light emitting diodes (LEDs) application. The main concern was the precise control of excitation and emission spectra for maximum light yield and color coordinate, which was carried out by changing the composition of the alkaline earth ions in host lattice. The Sr_2SiO_4: Eu-Ba_2SiO_4: Eu system was found to be excellent for white LED applications with excitation in the 380-465 nm region. Especially, the yellow light intensity from (Sr,Ba)SiO_4: Eu phosphors was comparable to YAG: Ce phosphors in case of blue LED excitation.