Color control by alteration of wavelength converting element

• US 7,902,566 B2
• Filed: 11/24/2008
• Issued: 03/08/2011
• 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: Camras, Michael D., Paolini, Steven, Chao Pujol, Oscar A., Epler, John E., Steranka, Frank M.
• Primary Examiner(s): Dang; Phuc T
• Application Number:
  US12/277,230
• Publication Number:
  US 20090072263A1
• Time in Patent Office: 834 Days
• Field of Search: 257/88, 257/89, 257/90, 257/91, 257/98, 438/22, 438/25, 438/28
• US Class Current: 257/98
• 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 device comprising:

a semiconductor light emitting element comprising a stack of semiconductor layers including an active region that emits light; and

a corrected wavelength converting member coupled to the semiconductor light emitting element, 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.

2. The device of claim 1, wherein producing the desired wavelength spectrum produces a desired correlated color temperature.

3. The device of claim 1, wherein producing the desired wavelength spectrum produces a point within a desired area in color space.

4. The device of claim 1, wherein the corrected wavelength converting member comprises a wavelength converting member that has been corrected to have less wavelength converting material that was initially coupled to the semiconductor light emitting element.

5. The device of claim 4, wherein the corrected wavelength converting member comprises a wavelength converting member that has been etched or ablated.

6. The device of claim 5, wherein the corrected wavelength converting member comprises a wavelength converting member that has been etched or ablated in a pattern of at least one of a design, symbol or emblem.

7. The device of claim 1, wherein the corrected wavelength converting member comprises a phosphor layer.

8. The device of claim 1, wherein the corrected wavelength converting member comprises a light converting ceramic.

9. The device of claim 1, wherein the corrected wavelength converting member is deposited on the semiconductor light emitting element.

10. The device of claim 1, wherein the corrected wavelength converting member is deposited on an optical element over the semiconductor light emitting element.

11. A device comprising:

a semiconductor light emitting element comprising a stack of semiconductor layers including an active region that emits light;

a corrected wavelength converting member over the light emitting element;

an optical element over the corrected wavelength converting member;

a first bonding layer between the light emitting element and the corrected wavelength converting member, the first bonding layer bonds the light emitting element and the corrected wavelength converting member together, wherein the corrected wavelength converting member is corrected to produce a desired wavelength spectrum; and

a second bonding layer between the corrected wavelength converting member and the optical element, the second bonding layer bonds the corrected wavelength converting member and the optical element together.

12. The device of claim 11, wherein the first bonding layer and the second bonding layer have bonding temperatures that are approximately the same.

13. The device of claim 11, wherein the second bonding layer has a higher bonding temperature than the first bonding layer.

14. The device of claim 11, wherein at least one of the first bonding layer and the second bonding layer comprises an oxide.

15. The device of claim 11, wherein at least one of the first bonding layer and the second bonding layer comprises a resin.

16. The device of claim 11, wherein at least one of the first bonding layer and the second bonding layer comprises a silicone.

17. The device of claim 11, wherein at least one of the first bonding layer and the second bonding layer includes a modified siloxane.

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