Mn2+ Concentration Effect on the Optical Properties of Zn2SiO4 : Mn Phosphors

Abstract

The optical properties of manganese-activated zinc silicate Zn2(~_~/Mn2=SiQ are investigated using pulse selective photon excitation. The light response due to the 4T~g- ~Alg transition is directly]inked to the relative concentration f isolated Mn 2 § and Mn 2 § pairs in this structure. The decay curves can be fitted by a diffusion-limited relaxation mechanism by considering two typ.es of centers with radiative lifetimes T0 equal to 15 and 1.75 ms, respectively. Mn 2+ activated Zn2SiO 4 is widely used as a high lumi-nance phosphor (P1) and as an antiflicker phosphor in low refresh-rate display application when co-activated with As (P39). 17 The green color emission band (centered at about 530 nm) is attributed to the spin flip transition of the d-or-bital electron associated with the Mn 2+ ion. The lumines-cence is ascribed to the 4T ~- 6A~g transition, which is for-bidden according to the selection rules. Zn2SiO~:Mn (willemite) is an efficient phosphor for plasma and cathodic displays. Its saturation under elec-