Semiconductor light-emitting device

• US 20060175624A1
• Filed: 02/09/2005
• Published: 08/10/2006
• Est. Priority Date: 02/09/2005
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Kaeding, John Francis, Pattison, Paul Morgan, Sharma, Rajat, Nakamura, Shuji
• Granted Patent: US 8,227,820 B2
• Time in Patent Office: Days
• US Class Current: 257/94
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01S 5/0207 Substrates having a special shape
• CPC Class Codes: H01S 5/10 Construction or shape of the optical resonator , e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region H01S5/20 takes precedence
• CPC Class Codes: H01S 5/1053 Comprising an active region having a varying composition or cross-section in a specific direction
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

A semiconductor light-emitting diode, and method of fabricating same, wherein an indium (In)-containing light-emitting layer, as well as subsequent device layers, is deposited on a textured surface. The resulting device is a phosphor-free white light source.

Claims

1. A method of fabricating a semiconductor light emitting device, comprising:

depositing an indium (In)-containing light-emitting layer, as well as subsequent device layers, on a textured surface.

2. The method of claim 1, wherein the step of depositing comprises:

(1) depositing a nucleation layer of gallium nitride (GaN) on a substrate;

(2) depositing an unintentionally-doped (UID) GaN template layer on the nucleation layer;

(3) depositing an n-type conductive GaN layer on the template layer;

(4) etching the deposited GaN layers to create the textured surface;

(5) re-growing the n-type conductive GaN layer on the textured surface; and

(6) depositing the indium-containing light-emitting layer on the re-grown n-type conductive GaN layer.

3. The method of claim 2, wherein the step (6) of depositing the indium-containing light-emitting layer on the re-grown n-type conductive GaN layer further comprises:

(i) depositing a quantum well layer of (Al,In,Ga)N on the re-grown n-type conductive GaN layer; and

(ii) depositing a barrier layer of (Al,In,Ga)N on the quantum well layer of (Al,In,Ga)N.

4. The method of claim 3, further comprising repeating the steps of depositing (i) and depositing (ii) to obtain a plurality of quantum well and barrier layers.

5. The method of claim 3, wherein varying fractions of indium are incorporated into the (In,Ga)N layers, depending on a position on the textured surface.

6. The method of claim 1, further comprising selectively texturing the surface.

7. The method of claim 6, wherein the textured surface is a partially textured surface.

8. The method of claim 6, further comprising controlling a ratio of a textured area of the surface to a non-textured area of the surface.

9. The method of claim 6, further comprising controlling the textured surface'"'"'s pattern.

10. The method of claim 6, further comprising controlling the textured surface'"'"'s dimensions.

11. The method of claim 6, wherein different patterns and depths of the textured surface produce different emission results.

12. The method of claim 1, wherein the device comprises a phosphor-free white light source.

13. A device manufactured according to the method of claim 1.

14. A semiconductor light emitting device, comprising an indium (In)-containing light-emitting layer, as well as subsequent device layers, deposited on a textured surface.

15. The device of claim 14, further comprising:

(1) a nucleation layer of gallium nitride (GaN) deposited on a substrate;

(2) an unintentionally-doped (UID) GaN template layer deposited on the nucleation layer;

(3) an n-type conductive GaN layer deposited on the template layer;

(4) the textured surface created by etching the deposited GaN layers;

(5) the n-type conductive GaN layer re-grown on the textured surface; and

(6) the indium-containing light-emitting layer deposited on the re-grown n-type conductive GaN layer.

16. The device of claim 15, wherein the indium-containing light-emitting layer deposited on the re-grown n-type conductive GaN layer further comprises:

(i) a quantum well layer of (Al,In,Ga)N deposited on the re-grown n-type conductive GaN layer; and

(ii) a barrier layer of (Al,In,Ga)N deposited on the quantum well layer of (Al,In,Ga)N.

17. The device of claim 16, further comprising a plurality of quantum well and barrier layers.

18. The device of claim 16, wherein varying fractions of indium are incorporated into the (In,Ga)N layers, depending on a position on the textured surface.

19. The device of claim 14, wherein the surface is selectively textured.

20. The device of claim 19, wherein the textured surface is a partially textured surface.

21. The device of claim 19, wherein a ratio of a textured area of the surface to a non-textured area of the surface is controlled.

22. The device of claim 19, wherein textured surface'"'"'s pattern is controlled.

23. The device of claim 19, wherein the textured surface'"'"'s dimensions are controlled.

24. The device of claim 19, wherein different patterns and depths of the textured surface produce different emission results.

25. The device of claim 14, wherein the device comprises a phosphor-free white light source.