Light-emitting device and manufacturing method thereof

• US 10,522,721 B2
• Filed: 07/27/2018
• Issued: 12/31/2019
• Est. Priority Date: 12/30/2015
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: Cheng, Ching-Tai, Shih, Chun-Hua, Renn, Yih-Hua
• Primary Examiner(s): Tran, Thien F
• Application Number:
  US16/047,734
• Publication Number:
  US 20180337313A1
• Time in Patent Office: 522 Days
• Field of Search: None
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/483 Containers
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• 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 33/60 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

Abstract

A light-emitting device includes a light-emitting element, a wavelength conversion layer, a light pervious element and a light-reflecting enclosure. The light-emitting element includes a top surface, a bottom surface, and a side surface between the top surface and the bottom surface. The wavelength conversion layer covers the top surface of the light-emitting element, and includes a plurality of wavelength conversion particles having an equivalent particle diameter D50. The light pervious element includes a recess structure and an outer wall. The light-reflecting enclosure surrounds the outer wall. The D50 of the wavelength conversion particles is not great than 10 μm. The recess structure is laterally overlapped with the side surface of the light-emitting element and the wavelength conversion layer.

Claims

1. A light-emitting device, comprising:

a light-emitting element, comprising a first top surface, a first bottom surface, a first side surface between the first top surface and the first bottom surface, and a plurality of electrical pads disposed under the first bottom surface;

a wavelength conversion layer, covering the first top surface, without covering the plurality of electrical pads, and comprising a second bottom surface, a second side surface, and a plurality of wavelength conversion particles with an equivalent particle diameter D50;

a light pervious element, comprising a third top surface and an third side surface, and disposed on the wavelength conversion layer; and

a light-reflecting enclosure surrounding the second side surface, the third side surface, and the plurality of electrical pads,

wherein the D50 is not great than 10 μ

m, and

wherein the wavelength conversion layer comprises a portion sandwiched between the light-reflecting enclosure and the light pervious element in a normal direction of the first top surface.

2. The light-emitting device according to claim 1, wherein the light pervious element comprises a light pervious adhesive layer and a light pervious substrate.

3. The light-emitting device according to claim 1, wherein the light-reflecting enclosure comprises a fourth top surface coplanar with the third top surface.

4. The light-emitting device according to claim 1, wherein the first side surface is separated from the light-reflecting enclosure by the light pervious element.

5. The light-emitting device according to claim 1, wherein the light-reflecting enclosure comprises a slant plane.

6. The light-emitting device according to claim 1, wherein the wavelength conversion layer comprises a quantum dot luminescent material.

7. The light-emitting device according to claim 1, wherein the wavelength conversion layer comprises an upper section and a bottom section, and a difference between an average of particle sizes of the wavelength conversion particles in the upper section and an average of particle sizes of the wavelength conversion particles in the bottom section is smaller than 10%.

8. The light-emitting device according to claim 1, wherein the wavelength conversion layer comprises an extending portion extending outward the first side surface.

9. The light-emitting device according to claim 1, wherein the wavelength conversion layer comprises a transparent binder.

10. The light-emitting device according to claim 9, wherein a weight percentage of the wavelength conversion particles to the wavelength conversion layer is less than 70%.

11. The light-emitting device according to claim 1, wherein the D50 of the wavelength conversion particles is in a range of 1 μ

m to 8 μ

m.

12. The light-emitting device according to claim 1, wherein the wavelength conversion layer has an average thickness, and a ratio of the average thickness to the D50 of the wavelength conversion particles is ranged from 6 to 20.

13. The light-emitting device according to claim 1, wherein the wavelength conversion layer has an average thickness, and a ratio of the average thickness to the D50 of the wavelength conversion particles is ranged from 8 to 15.

14. The light-emitting device according to claim 1, wherein the light-reflecting enclosure comprises a bottom portion arranged under the wavelength conversion layer and the light pervious element.

15. The light-emitting device according to claim 14, wherein the bottom portion has a fourth bottom surface coplanar with a bottom surface of the plurality of electrical pads.

16. The light-emitting device according to claim 1, wherein the light-reflecting enclosure comprises a lower portion arranged between a gap within the plurality of electrical pads.

17. The light-emitting device according to claim 1, wherein the light-reflecting enclosure comprises a portion directly contacting the first bottom surface.

18. The light-emitting device according to claim 1, wherein the plurality of electrical pads does not exceed the second side surface.

19. The light-emitting device according to claim 1, wherein the second side surface directly contacts the light-reflecting enclosure.

20. The light-emitting device according to claim 1, wherein light-reflecting enclosure has a thickness greater than that of the light pervious element in the normal direction of the first top surface.