Light emitting heterostructure

• US 20040099869A1
• Filed: 10/22/2003
• Published: 05/27/2004
• Est. Priority Date: 11/21/2002
• Status: Active Grant

• Current Assignee: Sensor Electronic Technology Incorporated (Seoul Semiconductor Co., Ltd.)
• Original Assignee: Sensor Electronic Technology Incorporated (Seoul Semiconductor Co., Ltd.)
• Inventors: Gaska, Remigijus, Shur, Michael S.
• Granted Patent: US 6,943,377 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: H01L 2933/0083 Periodic patterns for optical field-shaping in or on the semiconductor body or semiconductor body package, e.g. photonic bandgap structures
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/125 Distributed Bragg reflector [DBR] lasers
• CPC Class Codes: H01S 5/187 using Bragg reflection
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

An improved light emitting heterostructure. In particular, a nitride-based light emitting heterostructure is provided that includes a light generating structure and a distributed semiconductor heterostructure Bragg reflector structure formed above the light generating structure. In operation, the light generating structure generates light, a portion of which is reflected by the distributed semiconductor heterostructure Bragg reflector structure, thereby increasing the total amount of light that can be emitted from the heterostructure.

Claims

1. A light emitting heterostructure comprising:

a substrate;

a light generating structure formed over the substrate;

a distributed semiconductor heterostructure Bragg reflector (DBR) structure formed over the light generating structure; and

a p-type layer formed over the DBR structure.

2. The heterostructure of claim 1, further comprising an electron blocking layer formed between the light generating structure and the DBR structure.

3. The heterostructure of claim 1, further comprising:

a buffer layer formed on the substrate; and

a second layer formed on the buffer layer, wherein the light generating structure is formed on the second layer.

4. The heterostructure of claim 3, further comprising a contact layer formed on the second layer.

5. The heterostructure of claim 1, further comprising a contact layer formed above the DBR structure.

6. The heterostructure of claim 5, further comprising a metal layer formed on the contact layer.

7. The heterostructure of claim 1, further comprising an anodized aluminum layer formed over the DBR structure.

8. The heterostructure of claim 7, wherein the anodized aluminum layer forms a photonic crystal.

9. The heterostructure of claim 1, further comprising a reflective layer formed over the DBR structure.

10. The heterostructure of claim 1, wherein the substrate comprises a transparent substrate.

11. A light emitting device comprising:

a substrate;

an n-type layer formed over the substrate;

a light generating structure formed over the n-type layer;

a distributed semiconductor heterostructure Bragg reflector (DBR) structure formed over the light generating structure; and

a p-type layer formed over the DBR structure.

12. The device of claim 11, further comprising a reflective layer formed on the p-type layer.

13. The device of claim 12, further comprising a contact layer formed on the p-type layer, wherein the reflective layer and the contact layer form at least one of:

a set of alternating stripes and a set of alternating squares.

14. The device of claim 11, further comprising:

a first contact formed on the n-type layer; and

a second contact formed above the p-type layer.

15. The device of claim 11, wherein the device comprises at least one of:

a light emitting diode (LED), an ultraviolet LED, and a laser.

16. An ultraviolet light emitting heterostructure comprising:

an n-type layer;

a light generating structure formed over the n-type layer;

a distributed semiconductor heterostructure Bragg reflector (DBR) structure formed over the light generating structure; and

a p-type layer formed over the DBR structure.

17. The heterostructure of claim 16, further comprising an anodized aluminum layer formed over the p-type layer.

18. The heterostructure of claim 17, wherein the anodized aluminum layer and the p-type layer include a set of holes that form a photonic crystal.

19. The heterostructure of claim 16, wherein the p-type layer includes a set of holes.

20. The heterostructure of claim 19, wherein at least some of the set of holes is filled with a material having a different refractive index than the p-type layer.