Vertical light-emitting diode device and method of fabricating the same

Patent metadata

Field	Value
Publication number	US-10403791-B2
Application number	US-201715629051-A
Country	US
Kind code	B2
Filing date	Jun 21, 2017
Priority date	Jul 1, 2016
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

A vertical light-emitting diode device and a method of fabricating the same are provided. The device may include a conductive substrate serving as a p electrode, a p-type GaN layer provided on the conductive substrate, an active layer provided on the p-type GaN layer, an n-type GaN layer provided on the active layer, an n electrode pattern provided on the n-type GaN layer, a metal oxide structure filling a plurality of holes formed in the n-type GaN layer, and a seed layer provided on bottom surfaces of the holes and used to as a seed in a crystal growth process of the metal oxide structure.

First claim

What is claimed is:

1. A vertical light-emitting diode device, comprising:
a conductive substrate serving as a p electrode;
a p-type GaN layer on the conductive substrate;
an active layer on the p-type GaN layer;
an n-type GaN layer on the active layer;
an n electrode pattern on the n-type GaN layer;
a metal oxide structure filling a plurality of holes in the n-type GaN layer;
a seed layer on bottom surfaces of the holes, and
a sidewall on an inner side surface of each of the holes, wherein:
the conductive substrate, the p-type GaN layer, the active layer, the n-type GaN layer, and the n electrode pattern are in sequential order,
a refractive index of the metal oxide structure is less than that of the n-type GaN layer, and
the holes have a depth D and a diameter W such that D>W/4.

2. The device of claim 1 , wherein the sidewall comprises a metal or a metal alloy.

3. The device of claim 1 , wherein the sidewall comprises a dielectric material, and
a refractive index of the sidewall is less than that of the metal oxide structure.

4. The device of claim 1 , wherein the metal oxide structure comprises a material selected from the group consisting of zinc oxide (ZnO), zirconium oxide (ZrO 2 ), titanium oxide (TiO 2 ), chromium oxide (Cr 2 O), indium zinc oxide (IZO), indium tin zinc oxide (IZTO), indium oxide (In 2 O 3 ), or tin oxide (SnO 2 ).

5. The device of claim 1 , wherein the active layer emits light having a wavelength λ, and the diameter W of the hole is such that W/λ>2.405.

6. The device of claim 1 , wherein the depth D of the hole ranges from 200 nm to 3 μm.

7. The device of claim 1 , wherein the diameter W of the hole ranges from 300 nm to 4 μm.

8. The device of claim 1 , wherein the seed layer functions as a seed for crystal growth of the metal oxide structure.

9. The device of claim 1 , wherein the seed layer comprises zinc oxide (ZnO).

10. The device of claim 1 , wherein the active layer comprises gallium nitride (GaN).

11. The device of claim 10 , wherein the active layer generates light, the light propagates toward the n- or p-type semiconductor layer, most of the light is reflected by an interface between the n- or p-type semiconductor layer and air outside the n- or p-type semiconductor layer, and the light reflected by the interface between the n- or p-type semiconductor layer and the air is emitted through the metal oxide structure.

12. The device of claim 1 , further comprising a wafer bonding layer on the conductive substrate.

13. The device of claim 12 , wherein the wafer bonding layer includes at least one Sn-containing alloy.

14. The device of claim 13 , wherein the at least one Sn-containing alloy comprises an Au/Sn alloy or a Ni/Sn alloy.

15. The device of claim 12 , further comprising a metal reflection layer, the wafer bonding layer bonds the conductive substrate to the metal reflection layer, and p-type GaN layer is on the metal reflection layer.

16. The device of claim 15 , wherein the metal reflection layer reflects light from the active layer toward the n-type GaN layer.

17. The device of claim 15 , wherein the metal reflection layer comprises Ag, Al, or a combination thereof.

18. The device of claim 1 , wherein the n electrode pattern has a mesh structure.

19. The device of claim 1 , wherein the n electrode pattern forms an ohmic contact with the n-type GaN layer.

20. The device of claim 1 , wherein the n electrode pattern comprises a multi-layered structure including a Ti or Cr layer and optionally an Al, Ni and/or Au layer.

Assignees

• Seong Tae Yeon
• Kim Ki Seok
• Song Sung Joo
• Univ Korea Res & Bus Found

Inventors

• Seong Tae Yeon
• Kim Ki Seok
• Song Sung-Joo

Classifications

• H01L33/30

  Electricity · mapped topic

• H01L33/40

  Electricity · mapped topic

• H01L33/0075

  Electricity · mapped topic

• H01L33/38

  Electricity · mapped topic

• H01L33/20

  Electricity · mapped topic