| abstract |
The invention provides, amongst others for application in a lighting unit, a phosphor having the formula M 1-x-y-z Z z A a B b C c D d E e N 6-n O n :ES x ,RE y (I), with M = selected from the group consisting of divalent Ca, Sr, and Ba; Z = selected from the group consisting of monovalent Na, K, and Rb; B = selected from the group consisting of divalent Mg, Mn, Zn, and Cd; C = selected from the group consisting of trivalent B, Al and Ga; D = selected from the group consisting of tetravalent Si, Ge, Ti, and Hf; A = selected from the group consisting of monovalent Li, and Cu; E = selected for the group consisting of P, V, Nb, and Ta; ES = selected from the group consisting of divalent Eu, Sm and Yb; RE = selected from the group consisting of trivalent Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Tm; 0 ≤ x ≤ 0.2; 0 ≤ y ≤ 0.2; 0 < x+y ≤ 0.4; 0 ≤ z < 1; x + y + z < 1; 0 ≤ n ≤ 0.75; 0 ≤ a ≤ 2 (such as 0 ≤ b ≤ 0.5); 0 ≤ b ≤2;0 ≤ c ≤ 4;0 ≤ d ≤ 4; 0 ≤ e ≤ 4; a + b = 2; c + d + e = 4; and a + 2b + 3c +4d + e + y -z = 16 –n. |