Light emitting diode and fabrication method thereof

Patent metadata

Field	Value
Publication number	US-10367120-B2
Application number	US-201816186538-A
Country	US
Kind code	B2
Filing date	Nov 10, 2018
Priority date	Jun 13, 2016
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

A light-emitting diode includes a light-emitting epitaxial laminated layer with an upper surface; an ohmic contact layer over the light-emitting epitaxial laminated layer; an expanding electrode over the ohmic contact layer; a transparent insulating layer that covers the expanding electrode and the exposed ohmic contact layer, having a hole through the transparent insulating layer in a position corresponding to the expanding electrode; and a welding wire electrode over the transparent insulating layer and coupled to the expanding electrode via the hole.

First claim

The invention claimed is:

1. A light-emitting diode, comprising:
a light-emitting epitaxial laminated layer including:
a first semiconductor layer;
an active layer; and
a second semiconductor layer;

an ohmic contact layer over an upper surface of the light-emitting epitaxial laminated layer;
an expanding electrode over the ohmic contact layer;
a transparent insulating layer that covers the expanding electrode and an exposed ohmic contact layer and having a hole through the transparent insulating layer in a position corresponding to the expanding electrode; and
a welding wire electrode over the transparent insulating layer and coupled to the expanding electrode via the hole.

2. The light-emitting diode of claim 1 , wherein:
an upper surface of the light-emitting epitaxial laminated layer is divided into an ohmic contact region and a non-ohmic contact region′
the expanding electrode is provided in the ohmic contact region and extends towards to the non-ohmic contact region; and
the welding wire electrode is provided in non-ohmic contact region.

3. The light-emitting diode of claim 2 , wherein the non-ohmic contact region over the upper surface of the light-emitting epitaxial laminated layer is larger than the welding wire electrode.

4. The light-emitting diode of claim 2 , wherein the hole is distal from the ohmic contact region as much as possible.

5. The light-emitting diode of claim 2 , wherein, the hole is provided in the non-ohmic contact region.

6. The light-emitting diode of claim 2 , wherein, the non-ohmic contact region is distributed at both ends of the upper surface of the light-emitting epitaxial laminated layer; and the expanding electrode is a series of parallel linear structure, in which, the first and last ends are in the non-ohmic contact region, and the mid part contacts with the ohmic contact layer.

7. The light-emitting diode of claim 1 , wherein, refractive index of the transparent insulating layer is between that of the light-emitting epitaxial laminated layer and air.

8. The light-emitting diode of claim 1 , wherein, the transparent insulating layer, the light-emitting epitaxial laminated layer, and the welding wire electrode form an omnidirectional reflection system to avoid light absorption by the welding wire electrode.

9. The light-emitting diode of claim 1 , wherein, the transparent insulating layer in the ohmic contact region is λ/4n thick.

10. The light-emitting diode of claim 1 , wherein, a lower surface of the light-emitting epitaxial laminated layer is provided with a reflector.

11. A light-emitting system including a plurality of light-emitting diodes according to claim 1 .

12. The light-emitting system of claim 11 , wherein:
an upper surface of the light-emitting epitaxial laminated layer is divided into an ohmic contact region and a non-ohmic contact region;
the expanding electrode is provided in the ohmic contact region and extends towards to the non-ohmic contact region; and
the welding wire electrode is provided in non-ohmic contact region.

13. The light-emitting system of claim 12 , wherein the non-ohmic contact region over the upper surface of the light-emitting epitaxial laminated layer is larger than the welding wire electrode.

14. The light-emitting system of claim 11 , wherein the hole is provided in the non-ohmic contact region.

15. A fabrication method of a light-emitting diode, the method comprising:
1) forming a light-emitting epitaxial laminated layer, wherein, the light-emitting epitaxial laminated layer comprises a first semiconductor layer, an active layer and a second semiconductor layer;
2) forming an ohmic contact layer over an upper surface of the light-emitting epitaxial laminated layer;
3) forming an expanding electrode over the ohmic contact layer;
4) forming a transparent insulating layer over the expanding electrode which covers the expanding electrode. the exposed ohmic contact layer, and having a hole through the transparent insulating layer in a position corresponding to the expanding electrode; and
5) forming a welding wire electrode over the transparent insulating layer, which connects to the expanding electrode via the hole.

16. A fabrication method of a light-emitting diode, the method comprising:
1) forming a light-emitting epitaxial laminated layer over a growth substrate, comprising a first semiconductor layer, an active layer and a second semiconductor layer having a first surface and a second surface opposite to each other, wherein, the first surface is distal from the growth substrate;
2) forming an ohmic contact layer over the first surface of the light-emitting epitaxial laminated layer;
3) fabricating an expanding electrode over the ohmic contact layer;
4) providing a temporary substrate, and binding it to the first surface of the light-emitting epitaxial laminated layer;
5) removing the growth substrate to expose the second surface of the light-emitting epitaxial laminated layer;
6) forming a reflector over the second surface of the light-emitting epitaxial laminated layer;
7) providing a conductive substrate, and binding it to the reflector;
8) removing the temporary substrate to expose the expanding electrode, a part surface of the ohmic contact layer;
9) forming a transparent insulating layer, which covers the expanding electrode and the exposed ohmic contact layer;
10) setting a hole though the transparent insulating layer in a position corresponding to the expanding electrode; and
11) forming a welding wire electrode over the transparent insulating layer, which connects to the expanding electrode via the hole.
wherein the fabricated light-emitting diode comprises:
the light-emitting epitaxial laminated layer, which comprises:
the first semiconductor layer;
the active layer; and
the second semiconductor layer;

the ohmic contact layer over an upper surface of the light-emitting epitaxial laminated layer;
the expanding electrode over the ohmic contact layer;
the transparent insulating layer that covers the expanding electrode and the exposed ohmic contact layer and having a hole through the transparent insulating layer in a position corresponding to the expanding electrode; and
the welding wire electrode over the transparent insulating layer, which connects to the expanding electrode via the hole.

17. The method of claim 16 , wherein:
the first surface of the light-emitting epitaxial laminated layer is divided into an ohmic contact region and a non-ohmic contact region;
the expanding electrode is provided in the ohmic contact region and extends towards to the non-ohmic contact region; and
the welding wire electrode is provided in non-ohmic contact region.

18. The method of claim 17 , wherein the non-ohmic contact region over the upper surface of the light-emitting epitaxial laminated layer is larger than the welding wire electrode.

19. The method of claim 17 , wherein the hole is distal from the ohmic contact region as much as possible.

20. The method of claim 17 , wherein:
the non-ohmic contact region is distributed at both ends of the upper surface of the light-emitting epitaxial laminated layer; and
the expanding electrode is a series of parallel linear structure, in which, the first and last ends are in the non-ohmic contact region, and the mid part contacts with the ohmic contact layer.

Assignees

• Xiamen Sanan Optoelectronics Co Ltd

Inventors

• Meng Cheng
• Lu Yian
• Wu Chun-Yi
• Wang Duxiang

Classifications

• H01L2933/0016

  Electricity · mapped topic

• H01L33/14

  Electricity · mapped topic

• H01L33/44 Primary

  Electricity · mapped topic

• H01L33/387

  Electricity · mapped topic

• H01L2933/0025

  Electricity · mapped topic