Light emitting device having heat disipation terminal arranged on substrate

• US 10,193,045 B2
• Filed: 05/09/2018
• Issued: 01/29/2019
• Est. Priority Date: 05/21/2014
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Nakabayashi, Takuya, Hori, Akira
• Primary Examiner(s): Pham, Hoai V
• Application Number:
  US15/975,121
• Publication Number:
  US 20180261745A1
• Time in Patent Office: 265 Days
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/642 characterized by the shape
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

A light emitting device includes a substrate, light emitting elements, a sealing member, a light transmissive member and a heat dissipation terminal. The sealing member is in contact with at least a part of a side surface of each of the light emitting elements, is formed substantially in the same plane as the substrate, and a width of the sealing member between adjacent ones of the light emitting elements is larger than a width of the sealing member on an outside of an outermost one of the light emitting elements. The light transmissive member covers upper surfaces of the light emitting elements and a part of an upper surface of the sealing member, side surfaces of the light transmissive member being covered with the sealing member. The heat dissipation terminal is arranged generally in the center on a second main surface of the substrate and has a recess portion.

Claims

1. A light emitting device comprising:

a substrate having a first main surface, a second main surface that is opposite from the first main surface, and a mounting surface that is adjacent to at least the second main surface, the substrate including an insulating base material and a pair of connection terminals;

a plurality of light emitting elements mounted on the first main surface of the substrate;

a sealing member that is in contact with at least a part of a side surface of each of the light emitting elements, is formed substantially in the same plane as the substrate on the mounting surface, and a width of the sealing member between adjacent ones of the light emitting elements is larger than a width of the sealing member on an outside of an outermost one of the light emitting elements;

a light transmissive member that covers upper surfaces of the light emitting elements and a part of an upper surface of the sealing member, side surfaces of the light transmissive member being covered with the sealing member; and

a heat dissipation terminal that is arranged generally in the center on the second main surface of the substrate and that has a recess portion as viewed along a direction normal to the second main surface.

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

the heat dissipation terminal is connected to a terminal arranged on the first main surface of the substrate with at least one via.

3. The light emitting device according to claim 2, wherein

the substrate has an elongated shape with a lengthwise direction and a widthwise direction.

4. The light emitting device according to claim 3, wherein

the light emitting elements are aligned along the lengthwise direction.

5. The light emitting device according to claim 2, wherein

the at least one via is disposed generally at the center in a widthwise direction of the substrate.

6. The light emitting device according to claim 1, wherein

the insulating base material has a concave component with an inner curved surface, and the recess portion is arranged at a position corresponding to the concave component.

7. The light emitting device according to claim 6, wherein

the concave component opens at the second main surface and at the mounting surface.

8. The light emitting device according to claim 6, wherein

the concave component has an opening having a semicircular shape at the second main surface.

9. The light emitting device according to claim 6, wherein

the concave component is disposed closer to a side of the mounting surface with respect to the center of the substrate in the widthwise direction.

10. The light emitting device according to claim 1, wherein

the insulating base material is exposed in the recess portion of the heat dissipation terminal.

11. The light emitting device according to claim 1, wherein

a width of the heat dissipation terminal becomes narrower toward the mounting surface of the substrate.

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

the heat dissipation terminal includes a wide part and a narrow part.

13. The light emitting device according to claim 12, wherein

the narrow part becomes narrower toward the mounting surface of the substrate.

14. The light emitting device according to claim 12, wherein

the heat dissipation terminal includes an additional narrow part.

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

the recess portion is arranged between the narrow part and the additional narrow part.

16. The light emitting device according to claim 1, wherein

the light transmissive member contains a phosphor.

17. The light emitting device according to claim 16, wherein

the phosphor is KSF-based phosphors.

18. The light emitting device according to claim 1, wherein

the recess portion of the heat dissipation terminal includes an inner curved surface.

19. The light emitting device according to claim 1, wherein

the heat dissipation terminal is connected to a terminal arranged on the first main surface of the substrate with a pair of vias, with the recess portion being disposed between the pair of vias in a lengthwise direction of the substrate.

20. The light emitting device according to claim 1, wherein

the width of the sealing member on the outside of the outermost one of the light emitting elements is the width of the sealing member on the outside of the light emitting elements aligned along the lengthwise direction.