Silicate phosphor, method of manufacturing silicate phosphor, and light-generating device having silicate phosphor

A method of manufacturing a silicate phosphor, the method comprising:

• preparing a raw-materials mixture including a Ca-containing compound, a Si-containing compound and a Ce-containing compound;
• sintering the raw-material mixture;
• and
• cooling the sintered raw-material mixture to obtain a solidified silicate phosphor having a γ-phase of an orthorhombic crystal structure whose space group is Pbnm 62, and whose composition is represented by the following Chemical Formula 1,
• Ca2-x-y-zMxSiO4:yCe3+,zQ(0≦x<0.5,0<y≦0.1,0≦z<0.15) <Chemical Formula 1>
• wherein M represents at least one member selected from the group consisting of Mg, Sr, Ba, Zn, Na, Al, Ga, Ge, P, As and Fe, and Q represents at least one member selected from the group consisting of Eu2+, Mn2+, Tb3+, Yb2+ and Tm3+, and
• wherein the sintered raw-material mixture is cooled by a temperature ramp down speed of no less than about 15° C./min.

A light-emitting device comprising:

• a light source structured for generating at least an excitational light having a predetermined excitational wavelength;
• and
• a silicate phosphor disposed to be excited by the excitational light to responsively emit a light having a wavelength longer than the predetermined excitational wavelength, the silicate phosphor having a γ-phase of an orthorhombic crystal structure whose space group is Pbnm 62, and whose composition is represented by the following Chemical Formula 1,
• Ca2-x-y-zMxSiO4:yCe3+,zQ(0≦x<0.5,0<y≦0.1,0≦z<0.15) <Chemical Formula 1>
• wherein M represents at least one member selected from the group consisting of Mg, Sr, Ba, Zn, Na, Al, Ga, Ge, P, As and Fe, and Q represents at least member one selected from the group consisting of Eu2+, Mn2+, Tb3+, Yb2+ and Tm3+.