Nitride phosphor and production process thereof, and light emitting device

• US 20090309485A1
• Filed: 05/14/2009
• Published: 12/17/2009
• 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
• Granted Patent: US 7,964,113 B2
• Time in Patent Office: Days
• US Class Current: 313/503
• 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 process for production of a nitride phosphor which contains at least nitrogen, and absorbs at least a portion of light having a first luminescence spectrum and emits light having a second luminescence spectrum which is different from the above-mentioned first luminescence spectrum;

is characterized by having a step of firing in ammonia atmosphere.

2. The process for production of said nitride phosphor according to claim 1;

wherein said second luminescence spectrum has at least one or more peaks in the yellow to red range.

3. The process for production of said nitride phosphor according to claim 1;

wherein said firing is carried out using a crucible made of boron nitride material.

4. The process for production of said nitride phosphor according to claim 1;

wherein said nitride phosphor has a general formula LXMYN((_2,3)x+(_4,3)Y)R (wherein L is at least one or more elements selected from the Group II Elements consisting of Be, Mg, Ca, Sr, Ba, Zn, Cd and Hg, M is at least one or more elements selected from the Group IV Elements consisting of C, Si, Ge, Sn, Ti, Zr and Hf, and R is an activator).

5. The process for production of said nitride phosphor according to claim 4;

wherein said activator R is Eu.

6. The process for production of said nitride phosphor according to claim 4;

wherein said L and said R has a relation of the molar ratio of L R=1;

0.001 to 1.

7. The process for production of said nitride phosphor according to claim 1;

wherein said nitride phosphor has a general formula L_XM_YN_{((2/3)X+(4/3)Y)};

R (wherein L is at least one or more elements selected from the Group II Elements consisting of Mg, Ca, Sr and Ba, M is Si, and R is an activator.).

8. The process for production of said nitride phosphor according to claim 7;

wherein said activator R is Eu.

9. The process for production of said nitride phosphor according to claim 7;

wherein said L and said R has a relation of the molar ratio of L R=1;

0.001 to 1.

10. The process for production of said nitride phosphor according to claim 1;

further comprising a step of mixing a nitride of L, a nitride of M and a compound of R.

11. The process for production of said nitride phosphor according to claim 10;

wherein said activator R is Eu.

12. The process for production of said nitride phosphor according to claim 10;

wherein said L and said R has a relation of the molar ratio of L R=1;

0.001 to 1.

13. The nitride phosphor prepared by the process according to claim 1.

14. A light emitting device comprising a light emitting device which has at least a semiconductor light emitting element which emits light of a first luminescence spectrum, and a nitride phosphor which contains at least nitrogen, and absorbs at least a portion of light of said first luminescence spectrum and emits light of a second luminescence spectrum which is different from said first luminescence spectrum;

said nitride phosphor having been fired in an ammonia atmosphere.