Nitride phosphor and production process thereof, and light emitting device

• US 7,597,823 B2
• Filed: 10/03/2007
• Issued: 10/06/2009
• Est. Priority Date: 03/22/2002
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Tamaki, Hiroto, Naitou, Takahiro, Murazaki, Yoshinori, Kameshima, Masatoshi, Takashima, Suguru, Sakai, Kazuhiko, Yamada, Motokazu
• Primary Examiner(s): KOSLOW, CAROL M
• Application Number:
  US11/905,720
• Publication Number:
  US 20090072708A1
• Time in Patent Office: 734 Days
• Field of Search: 252/301.4 F, 252/301.6 F, 313/503, 257/98
• US Class Current: 252/301.40F
• CPC Class Codes: C01B 21/0602 with two or more other elements chosen from metals, silicon or boron
• CPC Class Codes: C01B 21/0821 Oxynitrides of metals, boron or silicon
• CPC Class Codes: C01P 2002/52 containing elements as dopants
• CPC Class Codes: C01P 2002/84 by UV- or VIS- data
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C04B 2235/3224 Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
• CPC Class Codes: C04B 2235/3225 Yttrium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3227 Lanthanum oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3229 Cerium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3286 Gallium oxides, gallates, indium oxides, indates, thallium oxides, thallates or oxide forming salts thereof, e.g. zinc gallate
• CPC Class Codes: C04B 2235/3852 Nitrides, e.g. oxynitrides, carbonitrides, oxycarbonitrides, lithium nitride, magnesium nitride
• CPC Class Codes: C04B 2235/3873 Silicon nitrides, e.g. silicon carbonitride, silicon oxynitride
• CPC Class Codes: C04B 2235/3895 Non-oxides with a defined oxygen content, e.g. SiOC, TiON
• CPC Class Codes: C04B 2235/764 Garnet structure A3B2(CO4)3
• CPC Class Codes: C04B 35/44 based on aluminates
• CPC Class Codes: C04B 35/584 based on silicon nitride
• CPC Class Codes: C04B 35/597 based on silicon oxynitride, e.g. SIALONS
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/77 containing rare earth metals
• CPC Class Codes: C09K 11/7702 : with zinc or cadmium
• CPC Class Codes: C09K 11/7703 : with alkaline earth metals
• CPC Class Codes: C09K 11/7728 : containing europium
• CPC Class Codes: C09K 11/773 : with zinc or cadmium
• CPC Class Codes: C09K 11/7731 : with alkaline earth metals
• CPC Class Codes: H01L 2224/32245 : the item being metallic
• CPC Class Codes: H01L 2224/45015 : being circular
• CPC Class Codes: H01L 2224/45124 : Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45139 : Silver (Ag) as principal constituent
• CPC Class Codes: H01L 2224/45144 : Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 : Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/45169 : Platinum (Pt) 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 2224/48464 : the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• CPC Class Codes: H01L 2224/48465 : the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/49107 : on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 : Applying permanent coating, e.g. protective coating
• 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 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/01021 : Scandium [Sc]
• CPC Class Codes: H01L 2924/01037 : Rubidium [Rb]
• CPC Class Codes: H01L 2924/01049 : Indium [In]
• CPC Class Codes: H01L 2924/01055 : Cesium [Cs]
• CPC Class Codes: H01L 2924/01066 : Dysprosium [Dy]
• CPC Class Codes: H01L 2924/01067 : Holmium [Ho]
• CPC Class Codes: H01L 2924/01068 : Erbium [Er]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/20751 : larger or equal to 10 microns less than 20 microns
• CPC Class Codes: H01L 2924/20752 : larger or equal to 20 microns less than 30 microns
• CPC Class Codes: H01L 2924/20753 : larger or equal to 30 microns less than 40 microns
• CPC Class Codes: H01L 2924/20754 : larger or equal to 40 microns less than 50 microns
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: Y02B 20/00 : Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

To provide a phosphor containing a comparatively much red component and having high light emitting efficiency, high brightness and further high durability, the nitride phosphor is represented by the general formula L_XM_YN_{((2/3)X+(4/3)Y)}:R or L_XM_YO_ZN_{((2/3)X+(4/3)Y−(2/3)Z)}:R (wherein L is at least one or more selected from the Group II Elements consisting of Mg, Ca, Sr, Ba and Zn, M is at least one or more selected from the Group IV Elements in which Si is essential among C, Si and Ge, and R is at least one or more selected from the rare earth elements in which Eu is essential among Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu); contains the another elements.

Claims

1. A nitride phosphor which is activated by at least one or more rare earth elements selected from a group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu, and which comprises at least one or more of the Group II Elements selected from a group consisting of Be, Mg, Ca, Sr, Ba and Zn, at least one or more of the Group IV Elements selected from a group consisting of C, Si, Ge, Sn, Ti, Zr and Hf, and N, the nitride phosphor containing B in the range of 1 ppm to 10000 ppm.

2. The nitride phosphor according to claim 1, further comprising O.

3. The nitride phosphor according to claim 1, of which crystal configuration is monoclinic or orthorhombic.

4. The nitride phosphor according to claim 1,

wherein said rare earth element is one or more of elements in which Eu is essential.

5. The nitride phosphor according to claim 1, further comprising one or more elements of the Group I Elements selected from a group consisting of Li, Na, K, Rb and Cs in the range of 0.1 ppm to 500 ppm.

6. The nitride phosphor according to claim 1, further comprising one or more elements selected from the Group I Elements consisting of Cu, Ag and Au, the Group III Elements consisting of Al, Ga and In, the Group IV Elements consisting of Ti, Zr, Hf, Sn and Pb, the Group V Elements consisting of P, Sb and Bi, and the Group VI Element consisting of S in the range of 0.1 ppm to 500 ppm.

7. The nitride phosphor according to claim 1, further comprising either the elements of Ni or Cr in the range of 1 ppm to 500 ppm.

8. The nitride phosphor according to claim 1, of which mean particle diameter is in a range of 2 μ

m to 15 μ

m.

9. The nitride phosphor according to claim 1, represented by a general formula L_XM_YN_{((2/3)X+(4/3)Y)}:

R or a general formula L_XM_YO_ZN<sub>((2/3)X+(4/3)Y−

(2/3)Z)</sub>;

R wherein L is at least one or more of the Group II Elements selected from a group consisting of Be, Mg, Ca, Sr, Ba and Zn, M is at least one or more of the Group IV Elements selected from a group consisting of C, Si, Ge, Sn, Ti, Zr, Hf. R is at least one or more of the rare earth elements selected from a group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu, X, Y and Z are 0.5≦

X≦

3, 1.5≦

Y≦

8, and 0<

Z ≦

3.

10. The nitride phosphor according to claim 9, of which crystal configuration is monoclinic or orthorhombic.

11. The nitride phosphor according to claim 9,

wherein said rare earth element is one or more of elements in which Eu is essential.

12. The nitride phosphor according to claim 9, further comprising one or more elements of the Group I Elements selected from a group consisting of Li, Na, K, Rb and Cs in the range of 0.1 ppm to 500 ppm.

13. The nitride phosphor according to claim 9, further comprising one or more elements selected from the Group I Elements consisting of Cu, Ag and Au, the Group III Elements consisting of Al, Ga and In, the Group IV Elements consisting of Ti, Zr, Hf, Sn and Pb, the Group V Elements consisting of P, Sb and Bi, and the Group VI Element consisting of S in the range of 0.1 ppm to 500 ppm.

14. The nitride phosphor according to claim 9, further comprising either the elements of Ni or Cr in the range of 1 ppm to 500 ppm.

15. The nitride phosphor according to claim 9, of which mean particle diameter is in a range of 2 μ

m to 15 μ

m.

16. The nitride phosphor according to claim 1 which absorbs a portion of light having a first luminescence spectrum and emits light having a second luminescence spectrum at a range different from said first luminescence spectrum, wherein the luminescence brightness and afterglow are controlled by the amount of B.

17. The nitride phosphor according to claim 16, of which crystal configuration is monoclinic or orthorhombic.

18. The nitride phosphor according to claim 16, further comprising one or more elements of the Group I Elements selected from a group consisting of Li, Na, K, Rb and Cs in the range of 0.1 ppm to 500 ppm.

19. The nitride phosphor according to claim 16, further comprising one or more elements selected from the Group I Elements consisting of Cu, Ag and Au, the Group III Elements consisting of Al, Ga and In, the Group IV Elements consisting of Ti, Zr, Hf, Sn and Pb, the Group V Elements consisting of P, Sb and Bi, and the Group VI Element consisting of S in the range of 0.1 ppm to 500 ppm.

20. The nitride phosphor according to claim 16, further comprising either the elements of Ni or Cr in the range of 1 ppm to 500 ppm.

21. The nitride phosphor according to claim 16, of which mean particle diameter is in a range of 2 μ

m to 15 μ

m.

22. A light emitting device comprising an excitation light source which emits light of a short wave length range of from near ultra violet to visible light and a phosphor which absorbs at least a portion of light from said excitation light source and emits light having a longer wave length range than light emitted from the excitation light source,

wherein said phosphor comprises a nitride phosphor which is activated by at least one or more rare earth elements selected from a group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu, and which comprises at least one or more of the Group II Elements selected from a group consisting of Be, Mg, Ca, Sr, Ba and Zn, at least one or more of the Group IV Elements selected from a group consisting of C, Si, Ge, Sn, Ti, Zr and Hf, and N, the phosphor containing B in the range of 1 ppm to 10000 ppm.

23. The light emitting device according to claim 22,

wherein said phosphor further comprises at least one or more of a phosphor emitting blue light, a phosphor emitting green light and a phosphor emitting yellow light.

24. The light emitting device according to claim 22,

wherein said excitation light source is a semiconductor light emitting element.

25. The light emitting device according to claim 22,

wherein a white light is emitted by mixing a portion of light emitted from said excitation light source which transmits between the particles of said phosphor with a portion of light emitted from said phosphor which is subjected to wavelength conversion by the light emitted from said excitation light source.