Green phosphors, methods of preparing the green phosphors, and white light-emitting devices including the green phosphors

A method of preparing a green phosphor, the method comprising:

• mixing an oxide of at least one of metal selected from the group consisting of Mg, Ca, Sr, Ba, and any combination thereof;
• an oxide of at least one of metal selected from the group consisting of Si, Ge, Al, Ga, and any combination thereof, and an oxide of at least one of metal selected from the group consisting of Eu Mn, Sb, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Er, Yb, Bi, and any combination thereof;
• heat treating the mixture at a temperature of about 900 to about 150° C. in air;
• mixing the heat treatment product and a halogenated material of Ca, Sr, Ba, or a combination comprising at least one of the foregoing;
• sintering the resultant mixture under a reducing atmosphere at a temperature of about 1,080 to about 1,200° C.;
• and
• grinding the sintering product.

A white light emitting device, comprising:

• an ultraviolet or blue light-emitting diode (LED);
• and
• a combination of
• a red phosphor,
• a green phosphor represented by Formula 1 below, and
• optionally, a blue phosphor,
• wherein in an X-ray diffraction pattern obtained by diffracting the green phosphor with Kα1 of Cu, a first intensity peak is positioned at a diffraction angle (2θ) of 30.5±1.0 and second through sixth intensity peaks are positioned at diffraction angles 24.8±1.0, 32.0±1.0, 35.0±1.0, 39.3±1.0 and 48.5±1.0 degrees, wherein the diffraction angle order does not match the second through sixth intensity peak order:
• (M11-xDx)pM2qOrAs [Formula 1]
• wherein
• M1 is at least one of metal selected from the group consisting of magnesium, calcium, strontium, barium, and any combination thereof,
• D is at least one of metal selected from the group consisting of europium, manganese, antimony, cerium, praseodymium, neodymium, samarium, terbium, dysprosium, erbium, ytterbium, bismuth, and any combination thereof,
• M2 is at least one selected from the group consisting of silicon, germanium, aluminum, gallium, and any combination thereof,
• A is at least one selected from the group consisting of chlorine, fluorine, bromine, iodine, and any combination thereof,
• and 2.7≦p≦3.3, 0.7≦q≦1.3, 3.5≦r≦4.5, 1.7≦s≦2.3, and 0<x≦0.1.