LIGHT EMITTING DIODE AND FABRICATION METHOD THEREOF

• US 20100136732A1
• Filed: 02/05/2010
• Published: 06/03/2010
• Est. Priority Date: 07/18/2003
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: Seong Jae Kim
• Inventors: KIM, Seong Jae
• Granted Patent: US 7,989,235 B2
• Time in Patent Office: Days
• US Class Current: 438/47
• CPC Class Codes: H01L 33/0025 comprising only AIIIBV compounds
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

A light emitting diode (LED) and a method for fabricating the same, capable of improving brightness by forming a InGaN layer having a low concentration of indium, and whose lattice constant is similar to that of an active layer of the LED, is provided. The LED includes: a buffer layer disposed on a sapphire substrate; a GaN layer disposed on the buffer layer; a doped GaN layer disposed on the GaN layer; a GaN layer having indium disposed on the GaN layer; an active layer disposed on the GaN layer having indium; and a P-type GaN disposed on the active layer. Here, an empirical formula of the GaN layer having indium is given by In(x)Ga(1-x)N and a range of x is given by 0<x<2, and a thickness of the GaN layer having indium is 50-200 Å.

Claims

1. A method for fabricating a light emitting diode, comprising:

forming a first conductive type semiconductor layer;

forming at least one GaN layer having indium on the first conductive type semiconductor layer;

forming at least one GaN layer directly on the GaN layer having indium;

forming an active layer directly on the GaN layer; and

forming a second conductive type semiconductor layer on the active layer, wherein the second conductive type semiconductor layer has a thickness of 750-1500 Å

.

2. The method according to claim 1, wherein an empirical formula of the GaN layer having indium is given by In_xGa_1-xN and a range of x is given by 0<

x<

0.2.

3. The method according to claim 1, wherein the active layer is formed of a multi-quantum well structure having an InGaN/GaN structure.

4. The method according to claim 1, wherein a thickness of the GaN layer is 10-30 Å

.

5. The method according to claim 1, wherein a thickness of the first conductive type semiconductor layer is 1-3 μ

m.

6. The method according to claim 1, wherein the active layer includes at least one well layer and at least one barrier layer formed in 1 period to 7 periods.

7. The method according to claim 1, further comprising:

preparing a substrate;

forming a buffer layer on the substrate; and

forming a first GaN layer on the buffer layer.

8. The method according to claim 7, wherein the buffer layer is formed of GaN-based material.

9. The method according to claim 7, wherein a thickness of the first GaN layer is 1-3 μ

m.

10. The method according to claim 7, wherein a total thickness of the first GaN layer and the first conductive type semiconductor layer is 2-6μ

m.

11. The method according to claim 7, wherein the first GaN layer includes an undoped GaN layer.

12. The method according to claim 1, further comprising:

forming a transparent metal on the second conductive type semiconductor layer, wherein the transparent metal is ITO (Indium-Tin-Oxide).

13. The method according to claim 1, wherein the second conductive type semiconductor layer includes at least one well layer and at least one barrier layer.

14. The method according to claim 1, wherein the GaN layer having indium has a thickness less than 200 Å

.

15. The method according to claim 14, wherein the GaN layer having indium has a thickness greater than 50 Å

and less than 200 Å

.

16. A method for fabricating a light emitting diode, comprising:

preparing a substrate;

forming a buffer layer on the substrate;

forming a first GaN layer on the buffer layer;

forming a first conductive type semiconductor layer on the first GaN layer;

forming at least one GaN layer having indium on the first conductive type semiconductor layer;

forming at least one second GaN layer directly on the GaN layer having indium;

forming an active layer directly on the second GaN layer; and

forming a second conductive type semiconductor layer on the active layer,

wherein a total thickness of the first GaN layer and the first conductive type semiconductor layer is 2-6 μ

m.

17. The method according to claim 16, wherein a thickness of the second GaN layer is 10-30 Å

.

18. The method according to claim 16, wherein the GaN layer having indium has a thickness less than 200 Å

.

19. The method according to claim 18, wherein the GaN layer having indium has a thickness greater than 50 Å

and less than 200 Å

.

20. A method for fabricating a light emitting diode, comprising:

forming a first conductive type semiconductor layer;

forming at least one GaN layer having indium on the first conductive type semiconductor layer;

forming at least one GaN layer directly on the GaN layer having indium, wherein the GaN layer has a thickness of 10-30 Å

;

forming an active layer including InGaN directly on the GaN layer, wherein the active layer includes at least one well layer and at least one barrier layer; and

forming a second conductive type semiconductor layer on the active layer, wherein the second conductive type semiconductor layer has a thickness of 750-1500 Å

.