LIGHT EMITTING DEVICE AND METHOD FOR MANUFACTURING THE SAME

• US 20080231169A1
• Filed: 03/19/2008
• Published: 09/25/2008
• Est. Priority Date: 03/23/2007
• Status: Active Grant

• Current Assignee: Xiamen San'An Optoelectronics Co.Ltd. (Sanan Optoelectronics Company Limited)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Agatani, Makoto, Morimoto, Taiji, Konishi, Masahiro, HATA, Toshio
• Granted Patent: US 7,872,418 B2
• Time in Patent Office: Days
• US Class Current: 313/500
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01B 1/10 sulfides
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/45169 Platinum (Pt) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• 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 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/0102 Calcium [Ca]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/01063 : Europium [Eu]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19107 : off-chip wires
• CPC Class Codes: H01L 33/50 : Wavelength conversion elements

Abstract

By using a light emitting device including a substrate and a light emitting unit, the light emitting unit including: a plurality of light emitting elements that are mounted on substrate and electrically connected to external electrodes; a first sealing member layer containing a first fluorescent material, formed to cover light emitting elements; and a second sealing member layer containing a second fluorescent material, formed on first sealing member layer, as well as a method for manufacturing thereof, it becomes possible to provide a light emitting device capable of suppressing color shifts and the like by the fluorescent materials, and of being easily manufactured, as well as a method for manufacturing the same.

Claims

1. A light emitting device comprising:

a substrate and a light emitting unit, wherein

the light emitting unit includes a plurality of light emitting elements mounted on the substrate and electrically connected to external electrodes,

a first sealing member layer that is formed to cover the light emitting elements and contains a first fluorescent material, and

a second sealing member layer that is formed on the first sealing member layer and contains a second fluorescent material.

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

the substrate is a metal substrate,

on the metal substrate, a wiring pattern is formed on a surface, and an insulating base member having a plurality of through holes that penetrate in a thickness direction is formed, and

the light emitting elements are mounted inside each through hole of the insulating base member on the metal substrate and electrically connected to the wiring pattern.

3. The light emitting device according to claim 2, wherein the plurality of light emitting elements are mounted to be aligned in one row in each of the through holes, and a plurality of linear wiring patterns are formed on a surface of the insulating base member in parallel with this linear alignment.

4. The light emitting device according to claim 3, wherein the light emitting elements are arranged to form a plurality of rows in parallel with one another.

5. The light emitting device according to claim 4, wherein a plurality of first sealing member layers are formed to cover each row of the light emitting elements that are arranged to form the plurality of rows in parallel with one another.

6. The light emitting device according to claim 2, wherein the light emitting elements arranged to form the plurality of rows in parallel with one another are electrically connected to the wiring pattern through a bonding wire commonly connected between the adjacent rows.

7. The light emitting device according to claim 6, wherein a plurality of first sealing member layers are formed to cover each row of the light emitting elements that are arranged so as to form the plurality of rows in parallel with one another.

8. The light emitting device according to claim 1, wherein the substrate is a metal substrate, an insulating base member is formed on the metal substrate, and metal plates are placed on the insulating base member in such a manner as to form a spaced portion therebetween, and each light emitting element is electrically connected to each metal plate while being also electrically connected to the adjacent metal plate with the spaced portion being interposed therebetween.

9. The light emitting device according to claim 8, wherein the plurality of light emitting elements are mounted to be aligned in one row, and the metal plates are placed in such a manner as to form a spaced portion in parallel with the row of the light emitting elements.

10. The light emitting device according to claim 9, wherein the light emitting elements are arranged to form a plurality of rows in parallel with one another.

11. The light emitting device according to claim 10, wherein a plurality of first sealing member layers are formed to cover each row of the light emitting elements that are arranged to form the plurality of rows in parallel with one another.

12. The light emitting device according to claim 1, wherein the plurality of light emitting elements are mounted to be aligned in one row.

13. The light emitting device according to claim 12, wherein the light emitting elements are arranged to form a plurality of rows in parallel with one another.

14. The light emitting device according to claim 13, wherein a plurality of first sealing member layers are formed to cover each row of the light emitting elements that are arranged to form the plurality of rows in parallel with one another.

15. The light emitting device according to claim 1, wherein a plurality of first sealing member layers are formed to cover the light emitting elements one by one.

16. The light emitting device according to claim 1, wherein the first sealing member layer is formed in such a manner that the plurality of light emitting elements are covered with the single first sealing member layer.

17. The light emitting device according to claim 1, wherein the first sealing member layer is formed in such a manner that all the light emitting elements are covered with the single first sealing member layer.

18. The light emitting device according to claim 1, wherein a second sealing member layer is formed to cover at least one portion of the first sealing member layer.

19. The light emitting device according to claim 1, wherein a second sealing member layer is formed on at least any one of a plurality of first sealing member layers.

20. The light emitting device according to claim 1, wherein the first sealing member layer is formed to have any one of a rectangular cross-sectional shape, a hexagonal cross-sectional shape, a round cross-sectional shape, and a cross-sectional shape with a plurality of straight line portions.

21. The light emitting device according to claim 1, which is used as one of a backlight light source of a liquid crystal display and a light source for illumination.

22. A method for manufacturing a light emitting device comprising the steps of:

installing a plurality of light emitting elements on a substrate and electrically connecting the light emitting elements to external electrodes;

forming a first sealing member layer containing a first fluorescent material in such a manner as to cover the light emitting elements;

measuring a chromaticity characteristic of the light emitting device after the formation of the first sealing member layer; and

forming a second sealing member layer on the first sealing member layer so as to adjust a chromaticity shift in accordance with the measured chromaticity characteristic.