SEMICONDUCTOR LIGHT EMITTING DEVICE

• US 20130126927A1
• Filed: 11/20/2012
• Published: 05/23/2013
• Est. Priority Date: 11/21/2011
• Status: Active Grant

• Current Assignee: LedComm LLC (IPValuation Partners, LLC)
• Original Assignee: Katsuji Iguchi
• Inventors: IGUCHI, Katsuji
• Granted Patent: US 8,946,749 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A semiconductor light emitting device includes a substrate having a wiring pattern formed thereon, and a semiconductor light emitting element mounted on one main surface of the substrate and electrically connected to the wiring pattern. The substrate has, on the one main surface, a serrated structure reflecting at least part of light emitted from said semiconductor light emitting element to the substrate, to a direction perpendicular to the one main surface.

Claims

1. A semiconductor light emitting device, comprising:

a substrate provided with a wiring pattern; and

a semiconductor light emitting element mounted on one main surface of said substrate and electrically connected to said wiring pattern;

wherein

said substrate has, on said one main surface, a serrated structure for reflecting at least part of light, emitted from said semiconductor light emitting element to said substrate, in a direction perpendicular to said one main surface.

2. The semiconductor light emitting device according to claim 1, wherein

said serrated structure includes a plurality of serrated structures positioned in concentric circular patterns with said semiconductor light emitting element being the center, when viewed two-dimensionally.

3. The semiconductor light emitting device according to claim 1, wherein

said serrated structure includes a plurality of serrated structures positioned in concentric rectangular patterns with said semiconductor light emitting element being the center, when viewed two-dimensionally.

4. The semiconductor light emitting device according to claim 1, wherein

said serrated structure includes a plurality of serrated structures positioned in concentric rectangular patterns on an inner side and in concentric circular patterns on an outer side, with said semiconductor light emitting element being the center, when viewed two-dimensionally.

5. The semiconductor light emitting device according to claim 1, wherein

said substrate further has a reflector portion having a substantially rectangular outer shape when viewed two-dimensionally and surrounding an edge;

and

said serrated structure includes a plurality of serrated structures extending in a direction perpendicular to the longitudinal direction of said substrate and positioned spaced from each other in said longitudinal direction.

6. The semiconductor light emitting device according to claim 5, wherein

said serrated structures are further positioned in rectangular patterns to surround said semiconductor light emitting element.

7. The semiconductor light emitting element according to claim 1, wherein

said serrated structure is positioned not to overlap with a position of connection between said wiring pattern and said semiconductor light emitting element.

8. The semiconductor light emitting device according to claim 1, wherein

said serrated structure is formed apart by a distance at least 1 and at most 1.5 times the thickness of the semiconductor light emitting element, from a peripheral side surface of said semiconductor light emitting element.

9. The semiconductor light emitting device according to claim 8, wherein

said serrated structure has a saw-tooth shape in transverse section, and has a plurality of inclinations serving as reflecting surfaces for reflecting light emitted from said semiconductor light emitting element;

and

when H represents the thickness of said semiconductor light emitting element, L represents the shortest distance between a crossing line of the closest inclination closest to said semiconductor light emitting element among the plurality of inclinations and said one upper surface and the peripheral side surface of said semiconductor light emitting element, and θ

represents an inner angle formed by the closest inclination and said one upper surface, said closest inclination satisfies the relation of 2θ

=90°

−

tan<sup>−

1</sup>(H/L).

10. The semiconductor light emitting device according to claim 9, wherein the relation of 30°

≦

θ

≦

45°

is satisfied.

11. The semiconductor light emitting device according to claim 9, wherein

where Lp represents distance between vertexes of adjacent peaks, h represents height of the vertex, and θ

p represents an inner angle of the inclination positioned between each of the vertexes in the transverse section of said serrated structure, the relation of Lp=h/tan θ

p is satisfied.

12. The semiconductor light emitting device according to claim 1 wherein

said serrated structure is formed of ceramic.

13. The semiconductor light emitting device according to claim 1, wherein

said serrated structure is formed of metal.

14. The semiconductor light emitting device according to claim 13, wherein

said serrated structure has its surface mirror-finished.

15. The semiconductor light emitting device according to claim 14, wherein

said serrated structure has its surface formed of silver.