Phosphor, method for producing a phosphor and use of a phosphor

• US 10,711,191 B2
• Filed: 07/13/2017
• Issued: 07/14/2020
• Est. Priority Date: 10/08/2013
• Status: Active Grant

• Current Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Fiedler, Tim, Bichler, Daniel, Lange, Stefan, Romer, Rebecca, Jermann, Frank, Thienel, Frauke, Huckenbeck, Barbara, Baumgartner, Alexander, Stoppelkamp, Vera, Bonisch, Norbert, Cui, Hailing
• Primary Examiner(s): Koslow, C Melissa
• Application Number:
  US15/649,385
• Publication Number:
  US 20170306224A1
• Time in Patent Office: 1,097 Days
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/646 Silicates
• CPC Class Codes: C09K 11/7721 Aluminates
• CPC Class Codes: C09K 11/7728 containing europium
• CPC Class Codes: C09K 11/77348 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• CPC Class Codes: C09K 11/7774 Aluminates
• 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 2224/73265 Layer and wire connectors
• 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 33/502 Wavelength conversion materials
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]

Abstract

A phosphor and a lighting device are disclosed. In an embodiment a lighting device includes a first phosphor disposed in a beam path of the primary radiation source, wherein the first phosphor has the formula Sr(Sr_aM_1−a)Si₂Al₂(N,X)₆:D,A,B,E,G,L, wherein element M is selected from Ca, Ba, Mg or combinations thereof, wherein element D is one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, alkali metals or Yb, wherein element A is selected from divalent metals different than those of the elements M and D, wherein element B is selected from trivalent metals, wherein element E is selected from monovalent metals, wherein element G is selected from tetravalent elements, wherein element L is selected from trivalent elements, wherein element X is selected from O or halogen, and wherein a parameter a is between 0.6 and 1.0.

Claims

1. A lighting device comprising:

a primary radiation source configured to emit primary radiation in a wavelength range between 300 nm and 570 nm; and

a first phosphor disposed in a beam path of the primary radiation source, the first phosphor configured to convert at least a portion of the primary radiation to secondary radiation within an orange to red wavelength range from 570 nm to 800 nm,

wherein the first phosphor has the formula;

Sr(Sr_aM<sub>1−

a</sub>)Si₂Al₂(N,X)₆;

D,A,B,E,G,L,

wherein element M is selected from the group consisting of Ca, Ba, Mg and combinations thereof,

wherein element D is one or more elements selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, alkali metals and Yb,

wherein element A is selected from divalent metals different than those of the elements M and D,

wherein element B is selected from trivalent metals,

wherein element E is selected from monovalent metals,

wherein element G is selected from tetravalent elements,

wherein element L is selected from trivalent elements,

wherein element X is selected from 0 or halogen,

wherein a parameter a is between 0.6 and 1.0, and

wherein the first phosphor crystallizes in space groups P1, P2, P1 or P2₁.

2. The lighting device according to claim 1, further comprising a second phosphor which is disposed in the beam path of the primary radiation source and has a different emission than the first phosphor.

3. The lighting device according to claim 1, further comprising a second phosphor disposed in a beam path of the secondary radiation and wherein the second phosphor is configured to absorb and convert at least a portion of the secondary radiation.

4. The lighting device according to claim 2, wherein the second phosphor includes the elements M, A, D, E, and X,

wherein the element M is one or more elements selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb,

wherein the element A is one or more elements selected from divalent metal elements other than those of the element M,

wherein the element D is one or more elements selected from tetravalent metal elements,

wherein the element E is one or more elements selected from trivalent metal elements,

wherein the element X is one or more elements selected from the group consisting of O, N, and F, and

wherein the second phosphor has the same crystal structure as CaAlSiN₃.

5. The lighting device according to claim 2, wherein the second phosphor has the formula:

(Gd,Lu,Tb,Y)₃(Al,Ga,D)₅(O,X)₁₂;

RE

or

(Gd,Lu,Tb,Y)₃(Al,Ga,D)₅(O,X)₁₂;

RE,

wherein the element X is selected from a halide, N or a divalent element,

wherein the element D is selected from a trivalent element or a tetravalent element, and

wherein RE is selected from rare earth metals as activators.

6. The lighting device according to claim 2, wherein the second phosphor has the formula:

(Gd,Lu,Tb,Y)₃(Al,Ga,D)₅(O,X)₁₂;

RE,

wherein the element X is selected from a halide or a divalent element,

wherein the element D is selected from a trivalent element or a tetravalent element,

wherein RE is selected from rare earth metals as activators,

wherein the second phosphor is disposed in the beam path of the primary radiation source, and

wherein the lighting device comprises a flash.

7. The lighting device according to claim 6, wherein the second phosphor has the formula:

Lu₃(Al<sub>1−

x</sub>Ga_x)₅O₁₂;

Ce or (Lu,Y)₃(Al<sub>1−

x</sub>Ga_x)₅(O)₁₂;

Ce,

wherein a cerium content is of 0.5-5 mol % based on the rare earth metals, and

wherein a gallium content x is between 0 and 0.5.

8. The lighting device according to claim 2, wherein the second phosphor has the formula:

(Gd,Y)₃(Al<sub>1−

x</sub>Ga_x)₅O₁₂;

Ce or (Tb,Y)₃(Al<sub>1−

x</sub>Ga_x)₅(O)₁₂;

Ce,

wherein a cerium content is of 1.5-5 mol %,

wherein a gallium content x is of 0 to 0.5, and

wherein the lighting device comprises a flash.

9. The lighting device according to claim 5, further comprising a secondary radiation source with phosphors disposed in the beam path thereof and configured to convert primary radiation to secondary radiation, wherein mixing the secondary radiation of the primary and secondary radiation sources results in an overall emission of radiation from the lighting device, and wherein the lighting device comprises a flash.

10. The lighting device according to claim 9, wherein a color range of the converted radiation from the secondary radiation source is different than a color range of the converted radiation from the primary radiation source.

11. The lighting device according to claim 10, wherein the primary and secondary radiation sources are operable with different currents and a color range of the overall emission radiation from the lighting device is selectable via different currents for the primary and secondary radiation sources.

12. The lighting device according to claim 10, further comprising an optical element arranged downstream of the phosphors of the primary and secondary radiation sources, wherein the optical element mixes the secondary radiation from the primary and secondary radiation sources to produce the overall emission of radiation.

13. The lighting device according to claim 2, wherein the primary radiation source emits the primary radiation in the wavelength range between 430 nm and 470 nm, wherein the second phosphor is a garnet of the formula:

(Gd,Lu,Y,Tb)₃(Al,Ga)₅(O)₁₂;

RE

or

(Lu,Y)₃(Al,Ga)₅(O)₁₂;

RE,

wherein RE is selected from a rare earth metal, and

wherein the lighting device is configured to produce a white light having a CRI≥

90.

14. The lighting device according to claim 13, wherein the element M in the first phosphor is Sr and Ca and the parameter a is as follows:

0.7≤

a, and wherein a proportion of an activator D is ≥

1.5%.

15. The lighting device according to claim 2, wherein the second phosphor is selected from at least one phosphor from the following phosphors:

a beta-SiAlON of the formula;

Si<sub>6−

z</sub>Al_zO_zN<sub>8−

z</sub>;

Eu with 0<

z≤

4,

nano-semiconductor materials as quantum dots,

nitridoorthosilicates of a general composition AE<sub>2−

x</sub>RE_xSiO<sub>4−

x</sub>N_x;

Eu,

wherein AE is selected from the group consisting of Sr, Ca, Ba and Mg,

wherein RE is selected from rare earth metals, or

of the general composition AE<sub>2−

x</sub>RE_xSi<sub>1−

y</sub>O<sub>4−

x−

2y</sub>N_x;

Eu.

16. The lighting device according to claim 1, wherein the primary radiation source comprises an LED, an OLED or a laser.

17. A light-emitting diode comprising:

at least one semiconductor chip configured to emit blue light; and

a phosphor arranged downstream of the semiconductor chip along a beam path,

wherein the phosphor is capable for emission of red light and has the formula;

SrxCa1-xAlSiN₃;

Eu,

wherein x is 0.8<

x≤

1, wherein between 0.1% and 5% inclusive of Sr, Ca and/or Sr/Ca lattice sites have been replaced by Eu,

wherein a full-width at half maximum is between at least 70 nm and at most 90 nm, and

wherein, if an x-ray structure analysis were to be performed, the phosphor in orthorhombic description exhibits a reflection (R) having the Miller indices 1 2 1.

18. A phosphor configured to emit red light,

wherein the phosphor has the formula:

SrxCa1-xAlSiN3;

Eu,

wherein x is;

0.8<

x≤

1,

wherein between 0.1% and 5% inclusive of Sr, Ca and/or Sr/Ca lattice sites are replaced by Eu,

wherein a full-width at half maximum is between 70 nm and 90 nm, and

wherein, if an a x-ray structure analysis were to be performed, the phosphor in orthorhombic description exhibits a reflection (R) having the Miller indices 1 21.