PHOSPHOR AND LIGHT EMITTING DEVICE HAVING THE SAME

• US 20150014725A1
• Filed: 07/14/2014
• Published: 01/15/2015
• Est. Priority Date: 07/12/2013
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: HONG, Ki Ho, KANG, Hyun Goo, KIM, Ji Hye, MOON, Ji Wook, LEE, Jae Moon, LEE, Ga Yeon
• Granted Patent: US 9,318,668 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: C09K 11/0838 Aluminates; Silicates
• CPC Class Codes: C09K 11/7706 Aluminates
• CPC Class Codes: C09K 11/77347 Silicon Nitrides or Silicon 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 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

Abstract

Disclosed are a phosphor and a light emitting device having the same. The light emitting device includes a light emitting chip, a plurality of phosphors to absorb a portion of light emitted from the light emitting chip and to emit lights having mutually different peak wavelengths, and a molding member provided on the light emitting chip and including the phosphors. The phosphors include a first phosphor to emit light having a first peak wavelength, a second phosphor to absorb the portion of the light emitted from the light emitting chip and to emit light having a second peak wavelength, and a third phosphor to absorb the portion of the light emitted from the light emitting chip and to emit light having a third peak wavelength. The first to third peak wavelengths have mutually different color spectrums, and a light emission spectrum in which the first to third peak wavelengths are mixed with each other has a luminous intensity having a substantially flat section in at least 30 nm at a peak wavelength thereof.

Claims

1. A light emitting device comprising:

a light emitting chip;

a plurality of phosphors to absorb a portion of light emitted from the light emitting chip and to emit lights having mutually different peak wavelengths; and

a molding member provided on the light emitting chip and including the phosphors,

wherein the phosphors comprise;

a first phosphor to emit light having a first peak wavelength;

a second phosphor to absorb the portion of the light emitted from the light emitting chip and to emit light having a second peak wavelength; and

a third phosphor to absorb the portion of the light emitted from the light emitting chip and to emit light having a third peak wavelength,

the first to third peak wavelengths have mutually different color spectrums, and

a light emission spectrum in which the first to third peak wavelengths are mixed with each other has a luminous intensity having a substantially flat section in at least 30 nm at a peak wavelength thereof.

2. The light emitting device of claim 1, wherein the first to third phosphors comprise mutually different nitride phosphors.

3. The light emitting device of claim 2, wherein the first to third phosphors comprise green, yellow, and red phosphors, respectively.

4. The light emitting device of claim 3, wherein the light emission spectrum has a peak wavelength in a range of 520 nm to 600 nm.

5. The light emitting device of claim 4, wherein the light emission spectrum has the flat section of the luminous intensity at the peak-wavelength in a peak wavelength range of 540 nm to 580 nm.

6. The light emitting device of claim 3, wherein each of the first to third peak wavelengths has a full width half max of 120 nm.

7. The light emitting device of claim 3, wherein the light emission spectrum comprises a greenish yellow light.

8. The light emitting device of claim 3, wherein the light emitting chip emits blue light or ultraviolet light, and the light emission spectrum comprises yellow light.

9. The light emitting device of claim 3, wherein the first phosphor has a content three times greater than a content of the second phosphor.

10. The light emitting device of claim 9, wherein the first phosphor has a content seven times greater than a content of the third phosphor.

11. The light emitting device of claim 3, wherein the first phosphor has a content having at least 70% of a sum of contents of the first to third phosphors.

12. The light emitting device of claim 1, wherein the flat section has a gradient having a deviation of 0.4% or less based on a horizontal linear line of the luminous intensity at the peak wavelength, and the flat section is in a range of 35 nm to 40 nm.

13. The light emitting device of claim 1, wherein the flat section is in a range of 0.29 to 0.33 of the full width half max of the light emission spectrum.

14. The light emitting device of claim 3, wherein the first phosphor comprises at least two selected from the group consisting of N, La, Si, Ba, Al, Ca, and Sr, the second phosphor comprises at least two selected from the group consisting of N, Mg, Ca, Sr, Ba, and Zn, and the third phosphor comprises at least one selected from the group consisting of N, Be, Mg, Ca, Sr, Ba, and Zn, and at least one selected from the group consisting of C, Si, Ge, Sn, Ti, Zr, and Hf.

15. The light emitting device of claim 3, wherein the molding member comprises a plurality of molding members, and at least two of the first to third phosphors are disposed in at least one of the molding members.

16. A light emitting device comprising:

a light emitting chip;

a plurality of phosphors to absorb a portion of light emitted from the light emitting chip and to emit lights having mutually different peak wavelengths; and

a molding member provided on the light emitting chip and comprising the phosphors,

wherein the phosphors have mutually different color spectrums,

a light emission spectrum of a mixture of lights emitted from the phosphors comprises yellow light, and

a luminous intensity at a peak wavelength of the light emission spectrum has a substantially flat section in a range of 35 nm to 40 nm.

17. The light emitting device of claim 16, wherein the first to third phosphors comprise mutually different nitride phosphors.

18. The light emitting device of claim 17, wherein the first to third phosphors comprise green, yellow, and red phosphors, respectively, and the light emission spectrum has the flat section of the luminous intensity at the peak-wavelength in a peak wavelength range of 540 nm to 580 nm.

19. The light emitting device of claim 18, wherein the first phosphor has a content which is three times greater than a content of the second phosphor, seven times greater than a content of the third phosphor, and at least 70% of a sum of contents of the first to third phosphors, and

wherein the first phosphor comprises at least two selected from the group consisting of N, La, Si, Ba, Al, Ca, and Sr, the second phosphor comprises at least two selected from the group consisting of N, Mg, Ca, Sr, Ba, and Zn, and the third phosphor comprises at least one selected from the group consisting of N, Be, Mg, Ca, Sr, Ba, and Zn, and at least one selected from the group consisting of C, Si, Ge, Sn, Ti, Zr, and Hf.

20. A phosphor comprising:

a first phosphor to emit light having a first peak wavelength;

a second phosphor to emit light having a second peak wavelength; and

a third phosphor to emit light having a third peak wavelength,

wherein the first to third phosphors pumps blue light or ultraviolet light to emit lights having mutually different color spectrums,

the first to third phosphors comprise mutually different nitride phosphors,

a light emission spectrum in which the first to third peak wavelengths are mixed with each other comprises yellow light,

a luminous intensity at a peak wavelength of the light emission spectrum has a substantially flat section in a range of 30 nm to 40 nm, and

the flat section has a gradient having a deviation of 0.4% or less based on a horizontal linear line of the luminous intensity at the peak wavelength.