Phosphor, method for manufacturing same, light emitting device, and image display device

Patent metadata

Field	Value
Publication number	US-9458379-B2
Application number	US-201314368927-A
Country	US
Kind code	B2
Filing date	May 30, 2013
Priority date	May 31, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

A chemically and thermally stable phosphor having unconventional light emitting properties and high light emitting intensity with an LED of 470 nm or less, includes an inorganic compound comprising: a crystal designated by A 3 (D,E) 8 X 14 , a crystal designated by Sr 3 Si 8 O 4 N 10 or an inorganic crystal having the identical crystal structure of the Sr 3 Si 8 O 4 N 10 crystal, which comprises A element, D element, X element, and optionally E element if necessary (A is one or more kinds selected from Li, Mg, Ca, Sr, and Ba; D is one or more kinds selected from Si, Ge, Sn, Ti, Zr, and Hf; X is one or more kinds selected from O, N, and F; and E is one or more kinds selected from B, Al, Ga, In, Sc, Y, and La.), into which M element is solid-solved (M is one or more kinds selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb.).

First claim

What is claimed is:

1. A phosphor comprising: an inorganic compound comprising:
a crystal represented by Sr 3 Si 8 O 4 N 10 or an inorganic crystal having an identical crystal structure to a crystal structure of the crystal represented by Sr 3 Si 8 O 4 N 10 , into which M element is solid-solved (here, M is one or more kinds of elements selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb),
wherein the inorganic crystal comprises: at least A element, D element, and X element (here, A is one or more kinds of elements selected from the group consisting of Li, Mg, Ca, Sr, and Ba; D is one or more kinds of elements selected from the group consisting of Si, Ge, Sn, Ti, Zr, and Hf; and X is one or more kinds of elements selected from the group consisting of O, N, and F),
wherein the inorganic crystal, if necessary, comprises: E element (here, E is one or more kinds of elements selected from the group consisting of B, Al, Ga, In, Sc, Y, and La), and
wherein the inorganic crystal is a crystal having a composition represented by A 3 D 8 X 14 or A 3 (D, E) 8 X 14 .

2. The phosphor according to claim 1 ,
wherein the A element comprises at least Sr or Ca; the D element comprises at least Si; the X element comprises at least N or a combination of N and O; and the E element comprises at least Al.

3. The phosphor according to claim 1 ,
wherein the inorganic crystal is a crystal of Ca 3 Si 8 O 4 N 10 .

4. The phosphor according to claim 1 ,
wherein the inorganic crystal is represented by a composition formula of Sr 3 Si 8−x Al x N 10−x O 4+x , or Ca 3 Si 8−x Al x N 10−x O 4+x , (where 0≦x≦8).

5. The phosphor according to claim 1 , wherein the M element is Eu.

6. The phosphor according to claim 1 , wherein the inorganic crystal is a crystal in a monoclinic system.

7. The phosphor according to claim 1 , wherein the inorganic crystal is a crystal in a monoclinic system and has a symmetry in a space group P2 1 /n, and lattice constants a, b, and c have values in following ranges:
a=0.48170±0.05 nm;
b=2.42320±0.05 nm; and
c=1.05600±0.05 nm.

8. The phosphor according to claim 1 ,
wherein:
the inorganic compound is represented by a composition formula of M d A e D f E g X h (here, d+e+f+g+h=1 in the formula;
M is one or more kinds of elements selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb;
A is one or more kinds of elements selected from the group consisting of Li, Mg, Ca, Sr, and Ba;
D is one or more kinds of elements selected from the group consisting of Si, Ge, Sn, Ti, Zr, and Hf;
E is one or more kinds of elements selected from the group consisting of B, Al, Ga, In, Sc, Y, and La; and
X is one or more kinds of elements selected from the group consisting of 0, N, and F), and

wherein parameters d, e, f, g, and h satisfy all following conditions:

0.00001≦d≦0.05;
0.05≦e≦0.3;
0.15≦f≦0.4;
0≦g≦0.15; and
0.45≦h≦0.65.

9. The phosphor according to claim 8 ,
wherein values of the parameters d, e, f, g, and h are within a range satisfying all conditions of:
d+e =(3/25)±0.05;

f+g =(8/25)±0.05; and

h =(14/25)±0.05.

10. The phosphor according to claim 8 ,
wherein values of the parameters f and g satisfy a condition of: 3/8≦f/(f+g)≦8/8.

11. The phosphor according to claim 8 ,
wherein:
the X element includes N and O,
the inorganic compound is represented by a composition formula of M d A e D f E g O h1 N h2 (here, d+e+f+g+h1+h2=1 and h1+h2=h in the formula), and
a condition of 0≦h1/(h1+h2)≦8/14 is satisfied.

12. The phosphor according to claim 8 ,
wherein the M element includes at least Eu.

13. The phosphor according to claim 8 ,
wherein:
the A element includes at least Sr or Ca,
the D element includes at least Si,
the E element includes at least Al if necessary, and
the X element includes at least O and N.

14. The phosphor according to claim 1 ,
wherein the inorganic compound is represented by a composition formula of: Eu y Sr 3−y Si 8−x Al x N 10−x O 4+x , or Eu y Ca 3−y Si 8−x Al x N 10−x O 4+x , and
wherein 0≦x<8 and 0.0001≦y≦2.

15. The phosphor according to claim 1 ,
wherein the phosphor emits fluorescence having a peak in a wavelength range of at least 560 nm and not exceeding 650 nm upon irradiation of an excitation source.

16. The phosphor according to claim 15 ,
wherein the excitation source is an electron beam; an X-ray or light having a wavelength that is at least 100 nm and not exceeding 450 nm, the light being vacuum ultraviolet rays, ultraviolet rays or visible light.

17. The phosphor according to claim 1 ,
wherein Eu is solid-solved into the crystal or the inorganic crystal and
wherein the phosphor emits fluorescence of yellow to red color having a wavelength of at least 560 nm and not exceeding 650 nm upon irradiation of light having a wavelength from 360 nm to 450 nm.

18. The phosphor according to claim 1 ,
wherein a color of light emitted upon irradiation of an excitation source satisfies, in terms of values of (x0, y0) of CIE 1931 chromaticity coordinates, conditions:
0.1≦ x 0≦0.7; and

0.2≦ y 0≦0.9.

19. A method of manufacturing a phosphor comprising:
firing a mixture of metal compounds being raw material mixture, which constitutes an inorganic compound of the phosphor according to claim 1 by firing the mixture, in a temperature range of at least 1,200° C. and not exceeding 2,200° C. in an inert atmosphere including nitrogen.

20. A light-emitting device comprising at least a light-emitting body and a phosphor (first phosphor),
wherein the phosphor recited in claim 1 is used as the phosphor (first phosphor).

21. The light-emitting device according to claim 20 ,
wherein the light-emitting body is an organic EL light-emitting body (OLED), a semiconductor laser, a laser diode (LD), or a light-emitting diode (LED) wherein any of the organic EL light-emitting body (OLED), the semiconductor laser, the laser diode (LD), and the light-emitting diode (LED) emits light of a wavelength of 330 to 500 nm.

22. The light-emitting device according to claim 20 ,
wherein the light-emitting device is a white light-emitting diode, an illuminating device including a plurality of white light-emitting diodes, or a backlight for a liquid crystal panel.

23. The light-emitting device according to claim 20 ,
wherein the light-emitting body emits ultraviolet or visible light having a peak wavelength of 300 to 450 nm, and
the light-emitting device emits white light or light other than the white light by mixing light emitted by the phosphor recited in claim 1 and light having a wavelength of 450 nm or more emitted by another phosphor.

24. The light-emitting device according to claim 20 , further comprising a blue phosphor being caused to emit light having a peak wavelength of 420 nm to 500 nm or less by the light-emitting body.

25. The light-emitting device according to claim 24 ,
wherein the blue phosphor is selected from a group consisting of AlN: (Eu, Si), BaMgAl 10 O 17 :Eu, SrSi 9 Al 19 ON 31 :Eu, LaSi 9 Al 19 N 32 :Eu, α-sialon:Ce, and JEM:Ce.

26. The light-emitting device according to claim 20 , further comprising a green phosphor being caused to emit light having a peak wavelength of at least 500 nm and not exceeding 550 nm by the light-emitting body.

27. The light-emitting device according to c

Assignees

• Nat Inst For Materials Science

Inventors

• Hirosaki Naoto
• Takeda Takashi
• Funahashi Shiro

Classifications

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W72/5522

  comprising gold [Au] · CPC title

• H10W72/01515

  Forming coatings · CPC title

• H10W72/075

  of bond wires · CPC title

• C30B1/04

  Isothermal recrystallisation · CPC title