Light Emitting Diode

• US 20080197373A1
• Filed: 06/23/2006
• Published: 08/21/2008
• Est. Priority Date: 06/24/2005
• Status: Active Grant

• Current Assignee: Seoul Viosys Co., Ltd. (Seoul Semiconductor Co., Ltd.)
• Original Assignee: Seoul Optodevice Company Limited (Seoul Semiconductor Co., Ltd.)
• Inventors: Kim, Kyoung Hoon
• Granted Patent: US 9,024,339 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/502 Wavelength conversion materials

Abstract

The present invention provides a light emitting diode which comprises a substrate, a light emitting layer including an N-type semiconductor layer and a P-type semiconductor layer formed on the substrate, and a wavelength conversion layer formed on the light emitting layer or on the back of the substrate. The wavelength conversion layer is formed of a Group in nitride semiconductor doped with rare earth elements. The rare earth elements include at least one of Tm, Er and Eu. According to a light emitting diode of the present invention, a desired color can be implemented in various ways by converting the wavelength of primary light emitted from a light emitting chip. Thus, the reliability and quality of products can be improved due to the uniform emission of light with a desired color. Further, since the existing semiconductor process can be utilized in the present invention, its fabrication process can be simplified, process cost and time can be reduced, and the compact products can be obtained.

Claims

1. A light emitting diode, comprising:

a substrate;

a light emitting layer including an N-type semiconductor layer and a P-type semiconductor layer formed on the substrate; and

a wavelength conversion layer formed on the light emitting layer,

wherein the wavelength conversion layer is formed of a Group III nitride semiconductor doped with rare earth elements.

4. The light emitting diode as claimed in claim 1, wherein the rare earth elements include at least one of Tm, Er and Eu.

5. The light emitting diode as claimed in claim 1, wherein the wavelength conversion layer is composed of at least one layer for emitting light with a wavelength shorter than that of light emitted from the light emitting layer.

6. The light emitting diode as claimed in claim 1, wherein when there are two or more wavelength conversion layers, a wavelength conversion layer from which light with a shorter wavelength is emitted is first formed.

7. The light emitting diode as claimed in claim 1, wherein the light emitting layer further includes an active layer between the N-type semiconductor layer and the P-type semiconductor layer.

8. The light emitting diode as claimed in claim 1, wherein the wavelength conversion layer is formed to extend up to sides of the P- type semiconductor layer, the N-type semiconductor layer and the substrate.

9. The light emitting diode as claimed in claim 1, wherein the wavelength conversion layer is grown using any one of Metal Organic Chemical Vapor Deposition (MOCVD), Chemical Vapor Deposition, Plasma Chemical Vapor Deposition (PCVD), Molecular Beam Epitaxy (MBE), or Hydride Vapor Phase Epitaxy (HVPE).

2. A light emitting diode, comprising:

a substrate;

a light emitting layer including an N-type semiconductor layer and a P-type semiconductor layer formed on the substrate; and

a wavelength conversion layer formed on the back of the substrate,

wherein the wavelength conversion layer is formed of a Group III nitride semiconductor doped with rare earth elements.

3. A light emitting diode as claimed in claim 2, wherein the substrate is a transparent or translucent substrate, and a reflection electrode is further formed on the light emitting layer.