LIGHT EMITTING DIODE

• US 20130001508A1
• Filed: 02/19/2012
• Published: 01/03/2013
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Advanced Optoelectronic Technology, Inc.
• Original Assignee: Advanced Optoelectronic Technology, Inc.
• Inventors: LIN, YA-WEN, HUANG, SHIH-CHENG, TU, PO-MIN, HUANG, CHIA-HUNG, YANG, SHUN-KUEI
• Granted Patent: US 8,754,438 B2
• Time in Patent Office: Days
• US Class Current: 257/13
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/145 with a current-blocking structure
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body

Abstract

An LED comprises a substrate, a buffer layer, an epitaxial layer and a conductive layer. The epitaxial layer comprises a first N-type epitaxial layer, a second N-type epitaxial layer, and a blocking layer with patterned grooves sandwiched between the first and second N-type epitaxial layers. The first and second N-type epitaxial layers make contact each other via the patterned grooves. Therefore, the LED enjoys a uniform current distribution and a larger light emitting area. A manufacturing method for the LED is also provided.

Claims

1. An LED, comprising:

a substrate, having a top face and a bottom face;

a buffer layer, disposed on the top face of the substrate;

an epitaxial layer, disposed on the buffer layer, comprising;

a first N-type epitaxial layer and a second N-type epitaxial layer;

a blocking layer, having patterned grooves, sandwiched between the first and the second N-type epitaxial layers, wherein the first and the second N-type epitaxial layers contacts to each other via a portion of the second N-type epitaxial layer in the patterned grooves;

a light emitting layer, disposed on the second N-type epitaxial layer; and

a P-type epitaxial layer, disposed on the light emitting layer; and

a conductive layer, disposed on the P-type epitaxial layer.

2. The LED as claimed in claim 1, wherein a P-type electrode is disposed on the conductive layer, the P-type electrode comprises a bonding portion located on one end of the conductive layer and an extending portion with a patterned structure.

3. The LED as claimed in claim 2, wherein the patterned structure of the extending portion is staggered with the patterned grooves inside the epitaxial layer.

4. The LED as claimed in claim 2, wherein an N-type electrode is disposed on the first N-type epitaxial layer where is opposite to the P-type electrode.

5. The LED as claimed in claim 2, wherein an N-type electrode is disposed inside the patterned grooves of the blocking layer where is opposite to the P-type electrode.

6. The LED as claimed in claim 1, wherein the substrate is sapphire.

7. An LED, comprising:

a substrate, having a top face and a bottom face;

a buffer layer, disposed on the top face of the substrate;

an epitaxial layer, disposed on the buffer layer, comprising a first N-type epitaxial layer and a second N-type epitaxial layer, a blocking layer with patterned grooves and sandwiched between the first and the second N-type epitaxial layers, a light emitting layer disposed on the second N-type epitaxial layer and a P-type epitaxial layer disposed on the light emitting layer;

an N-type electrode, contacting to the first N-type epitaxial layer;

a conductive layer, disposed on the P-type epitaxial layer; and

a P-type electrode, disposed on the conductive layer;

wherein the first and the second N-type epitaxial layers contact to each other via the patterned grooves.

8. The LED as claimed in claim 7, wherein the P-type electrode comprises a bonding portion located on one end of the conductive layer and an extending portion with a patterned structure.

9. The LED as claimed in claim 8, wherein the patterned structure of the extending portion is staggered with the patterned grooves inside the epitaxial layer.

10. The LED as claimed in claim 7, wherein the N-type electrode is disposed on the first N-type epitaxial layer.

11. The LED as claimed in claim 7, wherein the N-type electrode is disposed inside the patterned grooves of the blocking layer.

12. A manufacturing method for an LED, comprising:

providing a substrate having a buffer layer and a first N-type epitaxial layer sequentially disposing on a top face of the substrate;

forming a blocking layer on the first N-type epitaxial layer;

etching the blocking layer to form patterned grooves, wherein the patterned grooves penetrating the blocking layer to the first N-type epitaxial layer;

forming a second N-type epitaxial layer on the blocking layer, the second N-type epitaxial layer contacting to the first N-type epitaxial layer via a portion of the second N-type epitaxial layer in the patterned grooves;

forming a light emitting layer, a P-type epitaxial layer and a conductive layer sequentially disposed on the second N-type epitaxial layer; and

forming an N-type electrode to electrically connect with the first N-type epitaxial layer, and a P-type electrode on the conductive layer.

13. The manufacturing method for an LED as claimed in claim 12, wherein the buffer layer is made of a III-group nitride compound semiconducting material, and the first N-type epitaxial layer is a III-group nitride compound semiconductor contacting layer.

14. The manufacturing method for an LED as claimed in claim 13, wherein the blocking layer is a III-group nitride compound electron blocking layer.

15. The manufacturing method for an LED as claimed in claim 13, wherein the second N-type epitaxial layer is a III-group nitride compound semiconducting material.

16. The manufacturing method for an LED as claimed in claim 15, wherein the light emitting layer is a III-group nitride compound semiconductor active layer, the P-type epitaxial layer is a III-group nitride compound semiconducting material, and the conductive layer is a transparent conductive layer.

17. The manufacturing method for an LED as claimed in claim 12, wherein the N-type electrode is located on the blocking layer and makes contact with the first N-type epitaxial layer via a portion of the N-type electrode in the patterned grooves of the blocking layer.

18. The manufacturing method for an LED as claimed in claim 12, wherein the N-type electrode is located on the first N-type epitaxial layer.

19. The manufacturing method for an LED as claimed in claim 12, wherein a depression penetrating through the second N-type epitaxial layer, the blocking layer, the light emitting layer and the P-type epitaxial layer is formed for accommodating the N-type electrode therein.

20. The manufacturing method for an LED as claimed in claim 19, wherein the depression occupies an area which is substantially similar to that the N-type electrode occupies.