Color control by alteration of wavelength converting element

• US 8,202,742 B2
• Filed: 01/28/2011
• Issued: 06/19/2012
• Est. Priority Date: 11/12/2004
• Status: Active Grant

• Current Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Original Assignee: Philips Lumileds Lighting Company LLC (Apollo Global Management, Inc.), Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Paolini, Steven, Camras, Michael D., Chao Pujol, Oscar A., Steranka, Frank M., Epler, John E.
• Primary Examiner(s): DANG, PHUC T
• Application Number:
  US13/015,789
• Publication Number:
  US 20110132521A1
• Time in Patent Office: 508 Days
• Field of Search: 438/22, 438/25, 438/28, 257/88, 257/89, 257/90, 257/91, 257/98
• US Class Current: 438/22
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A light emitting device is produced by depositing a layer of wavelength converting material over the light emitting device, testing the device to determine the wavelength spectrum produced and correcting the wavelength converting member to produce the desired wavelength spectrum. The wavelength converting member may be corrected by reducing or increasing the amount of wavelength converting material. In one embodiment, the amount of wavelength converting material in the wavelength converting member is reduced, e.g., through laser ablation or etching, to produce the desired wavelength spectrum.

Claims

1. A method comprising:

providing a first bonding layer between a light emitting element and a wavelength converting member;

providing a second bonding layer between the wavelength converting member and an optical element, such that the first and second bonding layers are on opposite sides of the wavelength converting member;

bonding the light emitting element to the wavelength converting member with the first bonding layer; and

bonding the wavelength converting member to the optical element with the second bonding layer;

wherein the bonding of the wavelength converting member to the optical element occurs before bonding the light emitting element to the wavelength converting member.

2. The method of claim 1 wherein at least one of bonding the light emitting element to the wavelength converting member and bonding the wavelength converting member to the optical element together is done at elevated temperature.

3. The method of claim 1, wherein the bonding of the light emitting element to the wavelength converting member occurs at a first bonding temperature and the bonding of the wavelength converting member to the optical element occurs at a second bonding temperature.

4. The method of claim 3, wherein the first bonding temperature and second bonding temperature are approximately the same.

5. The method of claim 3, wherein the second bonding temperature is higher than the first bonding temperature.

6. The method of claim 1, wherein the wavelength converting member comprises a wavelength converting ceramic.

7. The method of claim 1, wherein at least one of the first bonding layer and the second bonding layer comprises an oxide.

8. The method of claim 1, wherein at least one of the first bonding layer and the second bonding layer comprises a resin.

9. The method of claim 1, wherein at least one of the first bonding layer and the second bonding layer comprises a silicone.

10. The method of claim 1, wherein at least one of the first bonding layer and the second bonding layer includes a modified siloxane.

11. The method of claim 1, wherein the light emitting element is mounted on a submount.

12. A method comprising:

providing a first bonding layer between a light emitting element and a wavelength converting member;

providing a second bonding layer between the wavelength converting member and an optical element, such that the first and second bonding layers are on opposite sides of the wavelength converting member;

bonding the light emitting element to the wavelength converting member with the first bonding layer; and

bonding the wavelength converting member to the optical element with the second bonding layer;

wherein the bonding of the light emitting element to the wavelength converting member and the bonding of the wavelength converting member to the optical element occur at approximately the same time.

13. A method comprising:

providing a first bonding layer between a light emitting element and a wavelength converting member;

providing a second bonding layer between the wavelength converting member and an optical element, such that the first and second bonding lavers are on opposite sides of the wavelength converting member;

bonding the light emitting element to the wavelength converting member with the first bonding layer; and

bonding the wavelength converting member to the optical element with the second bonding layer;

wherein the wavelength converting member comprises a corrected wavelength converting member, the corrected wavelength converting member is corrected to have an amount of wavelength converting material that is different than the amount of wavelength converting material initially coupled to the semiconductor light emitting element, the amount of wavelength converting material in the corrected wavelength converting member is sufficient to produce a desired wavelength spectrum.

14. The method of claim 13 wherein at least one of bonding the light emitting element to the wavelength converting member and bonding the wavelength converting member to the optical element is done at elevated temperature.

15. The method of claim 13, wherein the bonding of the light emitting element to the wavelength converting member and the bonding of the wavelength converting member to the optical element occur at approximately the same time.

16. The method of claim 13, wherein the bonding of the wavelength converting member to the optical element occurs before bonding the light emitting element to the wavelength converting member.

17. The method of claim 13, wherein the bonding of the light emitting element to the wavelength converting member occurs at a first bonding temperature and the bonding of the wavelength converting member to the optical element occurs at a second bonding temperature.

18. The method of claim 17, wherein the first bonding temperature and second bonding temperature are approximately the same.

19. The method of claim 17, wherein the second bonding temperature is higher than the first bonding temperature.

20. The method of claim 13, wherein the wavelength converting member comprises a wavelength converting ceramic.