Fluoride phosphor, fabricating method thereof, and light-emitting apparatus and backlight module employing the same

1. A method for fabricating a fluoride phosphor, comprising:

(a) providing a first solution, wherein the first solution is formed by dissolving potassium fluoride (KF) and either K 2 MnF 6 or KMnO 4 in a hydrofluoric acid solution;

(b) providing a second solution, wherein the second solution is formed by mixing a surfactant and a silane, and wherein the surfactant comprises sodium dodecyl sulfate (SDS; NaC 12 H 25 SO 4 );

(c) mixing the first solution and the second solution to form a precipitate; and

(d) collecting the precipitate after step (c).

2. The method for fabricating the fluoride phosphor as claimed in claim 1 , wherein the reaction time from step (a) to step (c) is in a range of about 10 minutes to about 30 minutes.

3. The method for fabricating the fluoride phosphor as claimed in claim 1 , wherein the molarity of potassium fluoride (KF) in the first solution is in a range of about 0.5 mol/L to about 2.7 mol/L.

4. The method for fabricating the fluoride phosphor as claimed in claim 1 , wherein the silane comprises tetraethyl orthosilicate (TEOS).

5. The method for fabricating the fluoride phosphor as claimed in claim 1 , wherein the mole percent of the surfactant and the precipitate is in a range of about 5 mol % to about 10 mol %.

6. The method for fabricating the fluoride phosphor as claimed in claim 5 , wherein the fluoride phosphor has a particle size in a range of about 6 μm to about 10 μm.

7. The method for fabricating the fluoride phosphor as claimed in claim 1 , wherein the second solution further comprises isopropanol.

8. The method for fabricating the fluoride phosphor as claimed in claim 7 , wherein the mole percent of isopropanol and the precipitate is in a range of about 500 mol % to about 1000 mol %.

9. The method for fabricating the fluoride phosphor as claimed in claim 8 , wherein the particle size of the fluoride phosphor is in a range of about 1 μm to about 3 μm.

10. The method for fabricating the fluoride phosphor as claimed in claim 1 , wherein the fluoride phosphor emits a red light having a peak wavelength in a range of about 600 nm to about 650 nm after being excited by a light having a peak wavelength in a range of about 300 nm to about 470 nm.

11. A fluoride phosphor fabricated by the method as claimed in claim 1 represented by the following formula:

K 2 [SiF 6 ]:Mn 4+ ,

wherein the fluoride phosphor has a particle size in a range of about 1 μm to about 10 μm.

12. The fluoride phosphor as claimed in claim 11 , wherein the fluoride phosphor has a particle size in a range of about 6 μm to about 10 μm.

13. The fluoride phosphor as claimed in claim 11 , wherein the fluoride phosphor has a particle size in a range of about 1 μm to about 3 μm.

14. The fluoride phosphor as claimed in claim 11 , wherein the fluoride phosphor emits a red light having a peak wavelength in a range of about 600 nm to about 650 nm after being excited by a light having a peak wavelength in a range of about 300 nm to about 470 nm.

15. A light-emitting apparatus, comprising:

an excitation light source;

a luminescent material disposed on the excitation light source, wherein the luminescent material comprises the fluoride phosphor as claimed in claim 11 .

16. The light-emitting apparatus as claimed in claim 15 , wherein the excitation light source comprises a light-emitting diode having an emission wavelength in a range of about 320 nm to about 500 nm.

17. The light-emitting apparatus as claimed in claim 15 , wherein the luminescent material further comprises a yellow light-emitting phosphor and/or a green light-emitting phosphor.

18. The light-emitting apparatus as claimed in claim 15 , wherein the lighting apparatus produces white light.

19. A backlight module, comprising at least one of the lighting apparatuses as claimed in claim 15 .

20. A method for fabricating a fluoride phosphor, comprising:

(a) providing a first solution, wherein the first solution is formed by dissolving potassium fluoride (KF) and either K 2 MnF 6 or KMnO 4 in a hydrofluoric acid solution;

(b) providing a second solution, wherein the second solution is formed by mixing a surfactant and a silane, and wherein the second solution further comprises isopropanol;

(c) mixing the first solution and the second solution to form a precipitate, wherein the mole percent of isopropanol and the precipitate is in a range of about 500 mol % to about 1000 mol %; and

(d) collecting the precipitate after step (c).