Granted Patent B2

US 12,509,630 · App. 16/198,108 · Granted Dec 30, 2025

Inventors: Zhengbo Yu (Shrewsbury, MA); Madis Raukas (Lexington, MA); John F. Kelso (Exeter, NH)

Assignee: OSRAM Opto Semiconductors GmbH

C09K11/7774C04B33/025C04B35/6261C04B35/62635C04B35/6264H10H20/8512H10H20/8514C04B2235/3217C04B2235/3222C04B2235/3225C04B2235/6025C04B2235/606C04B2235/608H10H20/0361

Abstract

Claims (43)

1 . A method for producing a ceramic converter element, the method comprising:

providing a phosphor as a starting material, the phosphor comprising a doped garnet;

mixing the phosphor and at least one metal oxide powder to form a mixture; and

processing the mixture to form a ceramic converter material in which the phosphor is embedded in a ceramic matrix material,

wherein the doped garnet comprises Y 3 Al 5 O 12 :Ln and the metal oxide powder comprises Y 3 Al 5 O 12 or Y 3 Al 5 O 12 and Al 2 O 3 , or

wherein the doped garnet comprises Lu 3 Al 5 O 12 :Ln and the metal oxide powder comprises Lu 3 Al 5 O 12 or Lu 3 Al 5 O 12 and Al 2 O 3 , and

wherein Ln is chosen from at least one of Ce, Gd, Pr or Eu.

2 . The method according to claim 1 , wherein the phosphor and the metal oxide powder are free of second phases and/or impurities.

3 . The method according to claim 1 , wherein the phosphor comprises Ce and/or Gd.

4 . The method according to claim 1 , wherein the phosphor comprises a quantum efficiency (QE) of at least 90%.

5 . The method according to claim 1 , wherein the mixing comprises milling.

6 . The method according to claim 1 , wherein the processing comprises adding at least one additive to the mixture to form a slurry, tape casting the slurry to form a green part, prefiring and/or debinding and sintering the green part to form the ceramic converter material.

7 . The method according to claim 6 , wherein the sintering is performed in a wet or dry hydrogen atmosphere or in a dry or wet hydrogen-nitrogen atmosphere.

8 . The method according to claim 6 , wherein the at least one additive is chosen from the group consisting of water, binders, de-foamers, dispersants, plasticizers, and mixtures thereof.

9 . The ceramic converter element produced using the method according to claim 1 .

10 . An optoelectronic component comprising:

an active layer sequence configured to emit electromagnetic radiation of a primary wavelength; and

the ceramic converter element produced with the method according to claim 1 , the ceramic converter element being located in a beam path of the active layer sequence and configured to convert the primary wavelength at least partly into a secondary wavelength, wherein the ceramic converter element comprises a quantum efficiency (QE) of at least 90%.

11 . A method for producing a ceramic converter element, the method comprising:

providing a phosphor as a starting material, the phosphor comprising a doped garnet;

mixing the phosphor and at least one metal oxide powder to form a mixture; and

processing the mixture to form a ceramic converter material in which the phosphor is embedded in a ceramic matrix material,

wherein the doped garnet comprises Y Al 5 O 12 :Ln and the metal oxide powder comprises Y 3 Al 5 O 12 or Y 3 Al 5 O 12 and Al 2 O 3 , or

wherein the doped garnet comprises Lu 3 Al 5 O 12 :Ln and the metal oxide powder comprises Lu 3 Al 5 O 12 or Lu 3 Al 5 O 12 and Al 2 O 3 ,

wherein the phosphor is a pre-synthesized phosphor with a cubic crystal phase with no second phases, and

wherein Ln is chosen from at least one of Ce, Gd, Pr or Eu.

12 . The method according to claim 11 , wherein the phosphor comprises a dopant that comprises a lanthanide.

13 . The method according to claim 12 , wherein the phosphor comprises Ce and/or Gd.

14 . The method according to claim 11 , wherein the phosphor comprises a quantum efficiency (QE) of at least 90%.

15 . A method for producing a ceramic converter element, the method comprising:

providing a phosphor as a starting material, the phosphor comprising a doped garnet;

mixing the phosphor and at least one metal oxide powder to form a mixture; and

processing the mixture to form a ceramic converter material in which the phosphor is embedded in a ceramic matrix material, and

wherein the doped garnet comprises Y 3 Al 5 O 12 :Ln and the metal oxide powder comprises Y 3 Al 5 O 12 or Y 3 Al 5 O 12 and Al 2 O 3 , or

wherein the doped garnet comprises Lu 3 Al 5 O 12 :Ln and the metal oxide powder comprises Lu 3 Al 5 O 12 or Lu 3 Al 5 O 12 and Al 2 O 3 ,

wherein Ln is selected from at least one of Ce, Gd, Pr, and Eu, and

wherein processing comprises:

adding at least one additive to the mixture to form a slurry,

tape casting the slurry to form a green part, and

prefiring and/or debinding and sintering the green part to form the ceramic converter material.

16 . The method according to claim 15 , wherein the phosphor and the metal oxide powder are free of second phases and/or impurities.

17 . The method according to claim 15 , wherein the phosphor comprises Ce and/or Gd.

18 . The method according to claim 15 , wherein the phosphor comprises a grain size d50 where 0.5 μm≤d50≤40 μm and d90≤45 μm, and wherein the metal oxide comprises a grain size d50 where 0.1 μm≤d50≤10 μm and d90≤15 μm.

Assignments (1)

Continuity (1)

References Cited (161)