LIGHT EMITTING DEVICE

• US 20090078957A1
• Filed: 02/05/2007
• Published: 03/26/2009
• Est. Priority Date: 02/06/2006
• Status: Active Grant

• Current Assignee: Showa Denko KK
• Original Assignee: Showa Denko KK
• Inventors: Hoshina, Takaharu
• Granted Patent: US 8,174,038 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• 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 2924/00012 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 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A light emitting device includes a board, a semiconductor light emitting element formed on the board optionally via a submount, a cap sealing the semiconductor light emitting element and a reflector provided surrounding the cap. The cap has top and bottom surfaces that are parallel to the top surface of the semiconductor light emitting element, and the spacing between the top and bottom surfaces is 1-3 times the longest diagonal or the diameter of the semiconductor light emitting element. Also disclosed is a process for producing the device.

Claims

1. A light emitting device comprising a board, a semiconductor light emitting element formed on the board optionally via a submount, a cap sealing the semiconductor light emitting element and a reflector provided surrounding the cap, wherein the cap has top and bottom surfaces that are parallel to the top surface of the semiconductor light emitting element, and the spacing between the top and bottom surfaces is 1-3 times the longest diagonal or the diameter of the semiconductor light emitting element.

2. A light emitting device according to claim 1, wherein the area ratio of the top and bottom surfaces of the cap (top surface/bottom surface) is 4 or greater.

3. A light emitting device according to claim 1, wherein the ratio between the lengths of the corresponding sides or the diameters of the top and bottom surfaces of the cap (top surface/bottom surface) is 2 or greater.

4. A light emitting device according to claim 1, wherein the angle formed between the top surface and sides of the cap is 40°

or smaller.

5. A light emitting device according to claim 1, wherein the area ratio of the top and bottom surfaces of the cap (top surface/bottom surface) is 1/4 or smaller.

6. A light emitting device according to claim 1, wherein the ratio between the lengths of the corresponding sides or the diameters of the top and bottom surfaces of the cap (top surface/bottom surface) is 1/2 or smaller.

7. A light emitting device according to claim 1, wherein the angle formed between the top surface and sides of the cap is 140°

or larger.

8. A process for production of a light emitting device comprising

a board, a semiconductor light emitting element formed on the board optionally via a submount, a cap sealing the semiconductor light emitting element and a reflector provided surrounding the cap, wherein the cap has top and bottom surfaces that are parallel to the top surface of the semiconductor light emitting element, and the spacing between the top and bottom surfaces is 1-3 times the longest diagonal or the diameter of the semiconductor light emitting element, which process comprises bonding the cap onto the semiconductor light emitting element with a material having a refractive index that is not more than the refractive index of the cap.