| abstract |
Red-emitting phosphors may comprise a nitride-based composition represented by the chemical formula: M a Sr b Si c Al d N e Eu f , in which M is at least one of Mg, Ca, Sr, Ba, Y, Li, Na, K and Zn, 0<a<1.0; 1.5<b<2.5; 4.0≤c≤5.0; 0≤d≤1.0; 7.5<e<8.5; and 0<f<0.1; a+b+f>2+d/v; and v is the valence of M. Furthermore, nitride-based red-emitting phosphor compositions may be represented by the chemical formula M x M' 2 Si 5-y A1 y N 8 :A, in which M is at least one of Mg, Ca, Sr, Ba, Y, Li, Na, K and Zn, and x>0; M' is at least one of Mg, Ca, Sr, Ba, and Zn; 0≤y≤0.15; A is at least one of Eu, Ce, Tb, Pr, and Mn; x>y/v and v is the valence of M; and wherein the red-emitting phosphors have the general crystalline structure of M' 2 Si 5 N 8 :A. |