Phosphor, phosphor manufacturing method, and white light emitting device

• US 8,653,549 B2
• Filed: 09/02/2010
• Issued: 02/18/2014
• Est. Priority Date: 08/10/2010
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Yoo, Jae Soo, Kim, Kyung Pil, Lee, Hyun Ju, Kim, Chang Soo
• Primary Examiner(s): HO, HOANG QUAN TRAN
• Application Number:
  US12/991,752
• Publication Number:
  US 20120037882A1
• Time in Patent Office: 1,265 Days
• Field of Search: None
• US Class Current: 257/98
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/77347 Silicon Nitrides or Silicon Oxynitrides
• CPC Class Codes: C09K 11/77348 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• 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 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

Provided are a phosphor, a phosphor manufacturing method, and a white light emitting device. The phosphor is represented as a chemical formula of aMO-bAlN-cSi₃N₄, which uses light having a peak wavelength in a wavelength band of about 350 nm to about 480 nm as an excitation source to emit visible light having a peak wavelength in a wavelength band of about 480 nm to about 680 nm. (where M is one selected from alkaline earth metals (0.2≦a/(a+b)≦0.9, 0.05≦b(b+c)≦0.85, 0.4≦c/(c+a)≦0.9)).

Claims

1. A luminescent material for use with a light emitting device, comprising:

aMO-bAlN-cSi₃N₄, where M is one element selected from alkaline earth metals, and 0.2≦

a/(a+b)≦

0.9, 0.05≦

b/(b+c)≦

0.85, and 0.4≦

c/(c+a)≦

0.9,

wherein at least one peak intensity of light in a wavelength of between about 480 nm to about 680 nm is provided by the luminescent material when excited by light from the light emitting device,

wherein the luminescent material is one of Sr₂Al₃Si₂O₂N_17/3;

Eu, or Sr₂Al₂Si₂O₂N_14/3;

Eu.

2. The luminescent material of claim 1, wherein the light emitting device emits one of UV light and blue light.

3. The luminescent material of claim 1, wherein at least one peak intensity of light in a wavelength of about 350 to about 480 nm is included in the light emitted by the light emitting device.

4. A light emitting device comprising:

a body;

a light emitting diode provided over the body; and

a resin provided over the light emitting diode, the resin having at least one of first luminescent material, second luminescent material or third luminescent material,

wherein at least one peak intensity of light in a wavelength of between about 510 nm to about 550 nm is provided by the first luminescent material based on light emitted from the light emitting diode, at least one peak intensity of light in a wavelength of between about 550 nm to about 580 nm is provided by the second luminescent material based on light emitted from the light emitting diode, and at least one peak intensity of light in a wavelength of between about 590 nm to about 650 nm is provided by the third luminescent material based on light emitted from the light emitting diode, and

wherein at least one of the first luminescent material, the second luminescent material, or the third luminescent material comprises the luminescent material as recited in claim 1.

5. The light emitting device according to claim 4, wherein the third luminescent material comprises red phosphor having about 0.1 part to about 60 parts by weight with respect to 100 parts by weight of the resin.

6. The light emitting device according to claim 4, wherein the first luminescent material is green phosphor having about 3 parts to about 50 parts by weight with respect to 100 parts by weight of the resin.

7. The light emitting device according to claim 4, wherein the second luminescent material is a yellow phosphor having about 0.1 part to about 20 parts by weight with respect to 100 parts by weight of the resin.

8. A light emitting device comprising:

a body;

a light emitting diode provided over the body;

at least one electrode electrically coupled to the light emitting diode; and

an encapsulant having a luminescent material provided over the light emitting diode,

wherein the luminescent material comprises at least one of first luminescent material or second luminescent material, and the encapsulant comprises a light transmissive resin, and

wherein at least one of the first luminescent material or second luminescent material phosphors includes the luminescent material as recited in claim 1.

9. The light emitting device according to claim 8, wherein the at least one of first luminescent material or the second luminescent material comprises M_aSi_bO_cN_d:

Eu, where M is at least one alkaline earth metal selected from a group consisting of Ra, Ba, Sr, Ca, Mg, and Be, and 1≦

a≦

7, 2≦

b≦

13, 1≦

c≦

18, and 0<

d≦

16, wherein at least one peak intensity of light in a wavelength of between about 480 nm to about 680 nm is provided by at least one of the first luminescent material or the second luminescent material when excited by light of light emitting diode.

10. The light emitting device according to claim 8, wherein the light emitting diode is configured to emit a blue light, the first luminescent material is one of a yellow phosphor and a red phosphor, and the second luminescent material is one of a green phosphor and a red phosphor.

11. The light emitting device according to claim 8, wherein the luminescent material further comprises a third luminescent material.

12. The light emitting device according to claim 11, wherein the light emitting diode is configured to emit one of a blue light or a UV light , the first luminescent material is one of a red phosphor and a blue phosphor, the second luminescent material is one of a yellow phosphor and a green phosphor, and a third luminescent material is one of a green phosphor and red phosphor.

13. The light emitting device according to claim 12, wherein the green phosphor is one of an oxynitride (ON)-based phosphor and a silicate-based phosphor, the yellow phosphor is one of a YAG phosphor, a TAG phosphor, and a silicate-based phosphor, and the red phosphor is a phosphor containing M, Al, Si, O, and N.

14. The light emitting device according to claim 12, wherein an amount of the yellow phosphor is the largest, an amount of the red phosphor is the smallest, and an amount of the green phosphor is less than that of the yellow phosphor and greater than that of the red phosphor.

15. The light emitting device according to claim 12, wherein the green phosphor emits light having a full width at half maximum (FWHM) of about 50 nm to about 100 nm, the yellow phosphor emits light having a FWHM of about 50 nm to about 100 nm or about 120 nm or more, and the red phosphor emits light having a FWHM of about 70 nm to about 120 nm.

16. The light emitting device according to claim 10, wherein the light emitted from the light emitting diode has a full width at half maximum (FWHM) of about 15 nm to about 40 nm.

17. The light emitting device according to claim 11, wherein the first luminescent material is a phosphor containing M, Al, Si, O, and N, the second luminescent material is a YAG phosphor, and the third luminescent material is one of a nitride-based phosphor and a silicate-based phosphor.

18. The light emitting device according to claim 11, wherein the first luminescent material is a phosphor containing M, Al, Si, O, and N and each of the second and third luminescent materials is a silicate-based phosphor.

19. The light emitting device according to claim 11, wherein the first luminescent material is one of a YAG phosphor and a silicate-based phosphor, the second luminescent material is a phosphor containing M, Al, Si, O, and N, and the third luminescent material is an oxynitride (ON)-based phosphor.

20. The light emitting device according to claim 11, wherein the encapsulant covers the light emitting diode, and the first, second, and third luminescent material are dispersed in the encapsulant.

21. The light emitting device according to claim 11, wherein the encapsulant covers the light emitting diode, the first luminescent material is disposed over the first encapsulant, the second phosphor is disposed over the first phosphor, and the third phosphor is disposed over the second phosphor.

22. The light emitting device according to claim 11, wherein the encapsulant comprises first, second, and third encapsulants,

wherein the first encapsulant covers the light emitting diode, the first luminescent material is disposed over the first encapsulant, the second encapsulant is disposed over the first luminescent material, the second luminescent material is disposed over the second encapsulant, the third encapsulant is disposed over the second luminescent material, and the third luminescent material is disposed over the third encapsulant.

23. The light emitting device according to claim 11, wherein the first luminescent material is disposed over a top surface of the light emitting diode, the second luminescent material is disposed over the first luminescent material and over a top surface side of the light emitting diode, the third luminescent material is disposed over the second luminescent material, and the encapsulant covers the light emitting diode and the first, second, and third luminescent materials.

24. The light emitting device according to claim 11, wherein the encapsulant comprises first and second encapsulants,

wherein the first luminescent material is disposed over a top surface of the light emitting diode, the first encapsulant covers the light emitting diode and the first luminescent material, the second luminescent material is disposed over the first encapsulant, the second encapsulant is disposed over the second luminescent material, and the third luminescent material is disposed over the second encapsulant.

25. The light emitting device according to claim 8, wherein the light emitting diode comprises a substrate having protrusion patterns, a first conductive type semiconductor layer over the substrate, an active layer over the first conductive type semiconductor layer, and a second conductive type semiconductor layer over the active layer,

wherein a first conductive type InGaN/GaN superlattice structure or InGaN/InGaN superlattice structure is disposed between the first conductive type semiconductor layer and the active layer, and a second conductive type A1GaN layer is disposed between the second conductive type semiconductor layer and the active layer.

26. The light emitting device according to claim 8, wherein the light emitting diode comprises a conductive support substrate, a second conductive type semiconductor layer over the conductive support substrate, an active layer over the second conductive type semiconductor layer, and a first conductive type semiconductor layer including a light extraction structure over the active layer,

wherein a first conductive type InGaN/GaN superlattice structure or InGaN/InGaN superlattice structure is disposed between the first conductive type semiconductor layer and the active layer, and a second conductive type AlGaN layer is disposed between the second conductive type semiconductor layer and the active layer.