Phosphor, method for producing the same and light-emitting device using the same

• US 8,398,892 B2
• Filed: 09/01/2008
• Issued: 03/19/2013
• Est. Priority Date: 09/03/2007
• Status: Active Grant

• Current Assignee: National Institute for Materials Science
• Original Assignee: National Institute for Materials Science, Showa Denko KK (Resonac Holdings Corp.)
• Inventors: Hirosaki, Naoto, Miki, Hisayuki, Shioi, Kousuke
• Primary Examiner(s): Koslow, Carol M
• Application Number:
  US12/676,094
• Publication Number:
  US 20100200874A1
• Time in Patent Office: 1,660 Days
• Field of Search: 252/301.4 F, 313/503, 257/98
• US Class Current: 252/301.4F
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/592 Chalcogenides
• CPC Class Codes: C09K 11/77348 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 33/502 Wavelength conversion materials

Abstract

The invention is a phosphor which includes a phosphor material having a composition represented by a general formula: M(0)_aM(1)_bM(2)_x−(vm+n)M(3)_(vm+n)−yO_nN_z−n, wherein M(0) is one or more elements selected from Li, Na, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Gd and Lu; M(1) is one or more activators selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm and Yb; M(2) is one or more elements selected from Si, Ge, Sn, Ti, Hf and Zr; M(3) is one or more elements selected from Be, B, Al, Ga, In, Tl and Zn; O is oxygen; N is nitrogen; and an atomic ratio of M(0), M(1), M(2), M(3), O and N is adjusted to satisfy the following: x, y and z satisfy 33≦x≦51, 8≦y≦12 and 36≦z≦56; a and b satisfy 3≦a+b≦7 and 0.001≦b≦1.2; m and n satisfy 0.8·me≦m≦1.2·me and 0≦n≦7 in which me=a+b; and v satisfies v={a·v(0)+b·v(1)}/(a+b) (wherein v(0) is a valence of M(0) ion and v(1) is a valence of M(1) ion). The invention also relates to a method for producing the phosphor and a light-emitting device using the phosphor.

Claims

1. A phosphor which comprises a phosphor material having a composition represented by a general formula:

M(0)_aM(1)_bM(2)<sub>x−

(vm+n)</sub>M(3)<sub>(vm+n)−

y</sub>O_nN<sub>z−

n</sub>, wherein

M(0) is one or more elements selected from Li, Na, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Gd, and Lu;

M(1) Eu;

M(2) is one or more elements selected from Si, Ge, Sn, Ti, Hf and Zr;

M(3) is one or more elements selected from Be, B, Al, Ga, In, Tl and Zn;

O is oxygen;

N is nitrogen; and

an atomic ratio of M(0), M(1), M(2), M(3), O and N is adjusted to satisfy the following;

x, y and z satisfy 33≦

x≦

51, 8≦

y≦

12 and 36≦

z≦

56;

a and b satisfy 3≦

a+b≦

7 and 0.001≦

b≦

1.2;

m and n satisfy 0.8 ·

me≦

m≦

1.2 ·

me and 0≦

n≦

7 in which me=a+b; and

v satisfies v={a·

v(0)+b·

v(1)}/(a+b), wherein v(0) is a valence of M(0) ion and v(1) is a valence of M(1) ion, and

wherein the phosphor emits 480 to 540-nm light.

2. The phosphor according to claim 1, wherein x=42, y=10 and z=46.

3. The phosphor according to claim 1, wherein M(0) is one or more elements selected from Ca, Sr and Ba.

4. The phosphor according to claim 1, wherein M(2) is Si and M(3) is Al.

5. The phosphor according to claim 1, wherein n≦

me.

6. The phosphor according to claim 1, wherein the content of the phosphor material is not less than 80% by volume and the remainder is one or more selected from β

-sialon, unreacted silicon nitride or aluminum nitride, oxynitride glass, SrSiAl₂N₂O₃, Sr₂Al₂Si₁₀N₁₄O₄, SrSi<sub>(10−

n)</sub>Al_(18+n)O_nN<sub>(32−

n)</sub>(n˜

1) and SrSi₆N₈.

7. The phosphor according to claim 1, wherein a transparent film is formed at least partially on a surface of the phosphor and a thickness of the transparent film is (10 to 180 )/n_k (nanometers) when the refractive index of the transparent film is n_k.

8. A light-emitting device comprising a light emitting source and a phosphor, wherein the phosphor is the phosphor according to claim 1.

9. The light-emitting device according to claim 8, comprising a light emitting source and a phosphor, wherein the phosphor further comprises CaAlSiN₃:

Eu.

10. The light-emitting device according to claim 8, wherein the light emitting source is one of a LED chip, an inorganic EL chip or an organic EL chip, each of which emits light at a wavelength of 330 to 500 nm.

11. The light-emitting device according to claim 8, wherein the phosphor is dispersed in a sealing resin formed to surround the LED chip.

12. The light-emitting device according to claim 10, wherein the phosphor is attached directly to the LED chip.

13. The light-emitting device according to claim 10, wherein the light-emitting device comprises a plurality of LED chips.

14. The phosphor according to claim 1, wherein, in powder X-ray diffraction measurement of the phosphor, at least one of the top five strongest diffraction lines selected from the X-ray diffraction pattern, has a diffraction angle (2θ

) ranging from 25°

to 27°

.