Light-emitting device

Patent metadata

Field	Value
Publication number	US-11973164-B2
Application number	US-202318092578-A
Country	US
Kind code	B2
Filing date	Jan 3, 2023
Priority date	Nov 4, 2019
Publication date	Apr 30, 2024
Grant date	Apr 30, 2024

Abstract

A light-emitting device includes a substrate including a top surface; a semiconductor stack including a first semiconductor layer, an active layer and a second semiconductor layer formed on the substrate, wherein a portion of the top surface is exposed; a distributed Bragg reflector (DBR) formed on the semiconductor stack and contacting the portion of the top surface of the substrate; a metal layer formed on the distributed Bragg reflector (DBR), contacting the portion of the top surface of the substrate and being insulated with the semiconductor stack; and an insulation layer formed on the metal layer and contacting the portion of the top surface of the substrate.

First claim

What is claimed is:

1. A light-emitting device, comprising:
a substrate comprising a top surface;
a plurality of light-emitting elements formed on the substrate, wherein the plurality of light-emitting elements comprises a first light-emitting element and a second light-emitting element, wherein each of the plurality of light-emitting elements comprises a first semiconductor layer, and a mesa comprising a second semiconductor layer and an active layer formed on the first semiconductor layer;
a first bottom electrode portion formed on the first light-emitting element and electrically connecting the first semiconductor layer of the first light-emitting element;
a first top electrode portion formed on the first light-emitting element and electrically connecting the second semiconductor layer of the first light-emitting element, wherein a first ratio of a first surface area of the first top electrode portion to that of the first bottom electrode portion on the first light-emitting element is between 1.1 and 1.6;
a second bottom electrode portion formed on the second light-emitting element and electrically connecting the first semiconductor layer of the second light-emitting element; and
a second top electrode portion formed on the second light-emitting element and electrically connecting the second semiconductor layer of the second light-emitting element.

2. The light-emitting device according to claim 1 , wherein the first bottom electrode portion and the first top electrode portion each comprises a comb shape.

3. The light-emitting device according to claim 2 , wherein the second bottom electrode portion and the second top electrode portion each comprises a comb shape.

4. The light-emitting device according to claim 1 , wherein the first bottom electrode portion or the first top electrode portion each comprises a comb shape.

5. The light-emitting device according to claim 1 , further comprising a connecting electrode portion electrically connect the first bottom electrode portion on the first light-emitting element and the second top electrode portion on the second light-emitting element.

6. The light-emitting device according to claim 1 , wherein the first bottom electrode portion is separated from the first top electrode portion by a shortest distance smaller than 50 μm and larger than 10 μm.

7. The light-emitting device according to claim 1 , wherein the first ratio of the first surface area of the first top electrode portion to that of the first bottom electrode portion on the first light-emitting element is between 1.2 and 1.5.

8. The light-emitting device according to claim 1 , further comprising a first electrode pad formed on a first plurality of light-emitting elements and a second electrode pad formed on a second plurality of light-emitting elements, wherein the first plurality of light-emitting elements comprises different amount from that of the second plurality of light-emitting elements.

9. The light-emitting device according to claim 1 , further comprising a first electrode pad formed on a first plurality of light-emitting elements and a second electrode pad formed on a second plurality of light-emitting elements, wherein the first plurality of light-emitting elements comprises same amount as that of the second plurality of light-emitting elements.

10. The light-emitting device according to claim 1 , further comprising a first lower electrode formed on the first semiconductor layer of the first light-emitting element and a first upper electrode formed on the second semiconductor layer of the first light-emitting element.

11. The light-emitting device according to claim 10 , further comprising a second lower electrode formed on the first semiconductor layer of the second light-emitting element and a second upper electrode formed on the second semiconductor layer of the second light-emitting element.

12. The light-emitting device according to claim 11 , further comprising a first current blocking layer formed under the first upper electrode, and a second current blocking layer formed under the second upper electrode.

13. The light-emitting device according to claim 12 , further comprising a first conductive layer formed between the first current blocking layer and the first upper electrode, and a second conductive layer formed between the second current blocking layer and the second upper electrode.

14. The light-emitting device according to claim 1 , further comprising an insulating layer covering the plurality of light-emitting elements, wherein the insulating layer comprises a Distributed Bragg Reflector (DBR).

15. The light-emitting device according to claim 1 , further comprising an insulating layer covering the plurality of light-emitting elements, wherein the insulating layer comprises a first most outside edge separated from an edge of the substrate by a distance between 5 μm and 60 μm.

16. The light-emitting device according to claim 1 , further comprising a street surrounding the light-emitting device, wherein the street exposes a portion of the top surface of the substrate.

17. The light-emitting device according to claim 1 , further comprising a metal layer formed on a sidewall of the plurality of light-emitting elements, wherein the metal layer is insulated from the plurality of light-emitting elements.

18. The light-emitting device according to claim 1 , wherein each of the plurality of light-emitting elements comprises a surrounding part comprising the first semiconductor layer surrounding the mesa.

19. The light-emitting device according to claim 4 , wherein the first bottom electrode portion comprises bottom branches and the first top electrode portion comprises top branches.

20. The light-emitting device according to claim 19 , wherein the bottom branches comprise a width larger or smaller than that of the top branches.

Assignees

• Epistar Corp

Inventors

• Lin Che-Hung
• Liao Chien-Chih
• HSU Chi-Shiang
• Kuo De-Shan
• Chen Chao-Hsing

Classifications

• H10H20/8314

  extending at least partially onto an outer side surface of the bodies · CPC title

• H10H20/814

  having reflecting means, e.g. semiconductor Bragg reflectors · CPC title

• H10H20/8162

  Current-blocking structures · CPC title

• H10H20/813 Primary

  having a plurality of light-emitting regions, e.g. multi-junction LEDs or light-emitting devices having photoluminescent regions within the bodies · CPC title

• H01L33/08 Primary

  Electricity · mapped topic