Green-light-emitting phase in Ba_3MgSi_2O_8:Eu~(2+), Mn~(2+) full-color phosphor for white-light-emitting diodes via addition of Si_3N_4

摘要

By adding Si_3N_4 to the Eu-, Mn-doped Ba_3MgSi_2O_8 upon firing, the formation of a new phase, Ba_2SiO_4, and its resultant variation of luminescent properties are investigated to compensate the green-light-emission for full-color. Upon addition of Si_3N_4, a approx507-nm peaked band emission of Eu in Ba_2SiO_4 was induced in coexistence with the concurrent blue-, and red-light-emissions of Eu and Mn in Ba3MgSi2O_8. Amount of each phase and as such the transfer of energy in between can be tuned by varying the amo unt of Si_3N_4 added, resulting in an interactive change of intensity in between Eu for blue-, green-band-transitions and Mn for red-band-transition in two different phases, due to the indirect contribution of Si_3N_4 to the formation of Ba_2SiO_4 and red-shift of photoluminescence. Consequently, white-light with CIE chromaticity coordinate (0.2605, 0.3084) at an optimized amount of Si_3N_4 has been achieved with this nitride-added adjustable strategy.