Light-emitting device and manufacturing method thereof

• US 20160190406A1
• Filed: 12/22/2015
• Published: 06/30/2016
• Est. Priority Date: 12/24/2014
• Status: Abandoned Application

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: LIU, Chien-Liang, HSU, Ming-Chi, YU, Jen-Chieh
• Application Number:
  US14/757,365
• Publication Number:
  US 20160190406A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

This disclosure discloses a light-emitting device. The light-emitting device includes a light-emitting stack with a first (top) surface, a bottom surface and at least one side surface connected to the first surface and the bottom surface, a light-reflective enclosure with a second (top) surface, a contact electrode formed on the bottom surface of the light-emitting layer, and a wavelength converting layer. Moreover, the light-reflective enclosure surrounds the side surface of the light-emitting stack and exposes to the first surface. The wavelength converting layer covers the first surface and the second surface. In addition, the second surface has a plurality of fine concave structures distributed on the second surface.

Claims

1. A light-emitting device, comprising:

a light-emitting stack comprising a first surface, a bottom surface and at least one side surface connected to the first surface and the bottom surface;

a light-reflective enclosure, comprising a second surface, surrounding the side surface and, exposing the first surface;

a contact electrode formed on the bottom surface of the light-emitting stack; and

a wavelength converting layer covering the first surface and the second surface;

wherein the second surface comprises a plurality of fine concave structures.

2. The light-emitting device of claim 1, wherein a roughness of the first surface is smaller than a roughness of the second surface.

3. The light-emitting device of claim 1, wherein the wavelength converting layer fills the plurality of fine concave structures.

4. The light-emitting device of claim 1, wherein the wavelength converting layer comprises a thickness, and a variation of the thickness and an average thickness is less than 5%.

5. The light-emitting device of claim 1, wherein the first surface to the contact electrode has a first height and the second surface to the contact electrode has a second height, and wherein a variation of the first height and the second height is less than 40 μ

m.

6. The light-emitting device of claim 1, wherein a roughness of root-mean-square (RMS) of the second surface is greater than 100 nm.

7. The light-emitting device of claim 1, wherein the light-reflective enclosure comprises a light-reflective material and a binding agent.

8. The light-emitting device of claim 1, further comprising an extension pad formed on the contact electrode, and the extension pad comprises a first surface area greater than a second surface area of the contact electrode.

9. The light-emitting device of claim 1, further comprising a reflective layer surrounding the contact electrode.

10. A method of making a light-emitting device, comprising:

providing a light-emitting stack and a contact electrode, wherein the light-emitting stack comprises a first surface, a bottom surface, and a side surface connected to the first surface and the bottom surface, and the contact electrode is formed on the bottom surface;

connecting the light-emitting stack to a temporary substrate, and exposing the side surface and one of the first surface and the bottom surface from the temporary substrate;

covering a light-reflective material on the side surface and one of the first surface and the bottom surface exposed from the temporary substrate;

removing a portion of the light-reflective material to expose the first surface or the bottom surface and forming a light-reflective enclosure comprising a second surface, wherein the second surface comprises a plurality of fine concave structures distributed on the second surface; and

removing the temporary substrate.

11. The method of making the light-emitting device of claim 10, wherein the temporary substrate exposes the first surface.

12. The method of making the light-emitting device of claim 10, further comprising covering the first surface and the second surface by a wavelength converting layer.

13. The method of making the light-emitting device of claim 10, wherein covering the light-reflective material comprises a transfer molding or a compression molding.

14. The method of making the light-emitting device of claim 10, wherein removing a portion of the light-reflective material comprises a wet blasting deflash.

15. A light-emitting device, comprising:

a light-emitting stack comprising a first surface, a bottom surface and at least one side surface connected to the first surface and the bottom surface;

a light-reflective enclosure, comprising a second surface, an inner sidewall, and an outer sidewall, surrounding the side surface of the light-emitting stack, exposing to the first surface, wherein the second surface comprises a first convex structure protruded outward from the inner sidewall to the outer sidewall;

a contact electrode formed on the bottom surface of the light-emitting stack; and

a wavelength converting layer covering the first surface and the second surface.

16. The light-emitting device of claim 15, wherein the light-reflective enclosure comprises a corner, and a position of the first convex structure corresponding to the corner.

17. The light-emitting device of claim 15, wherein a portion of the inner sidewall is lower than a portion of the outer sidewall.

18. The light-emitting device of claim 15, wherein the light-reflective enclosure further comprises a second convex structure and a flat region disposed between the first convex structure and the second convex structure.

19. The light-emitting device of claim 15, wherein the first convex structure comprises an arc-like structure.