Light emitting device

• US 20110095260A1
• Filed: 06/01/2010
• Published: 04/28/2011
• Est. Priority Date: 10/28/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Kim, Taek
• Granted Patent: US 9,035,324 B2
• Time in Patent Office: Days
• US Class Current: 257/13
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• 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 33/20 with a particular shape, e.g. curved or truncated substrate

Abstract

A light emitting device may include a semiconductor light emitting diode which may include a first nitride semiconductor layer doped as an n-type, a second nitride semiconductor layer doped as a p-type, and a first active layer provided between the first and second nitride semiconductor layers, and a nano light emitting diode array in which a plurality of nano light emitting diodes may be arranged on the semiconductor light emitting diode so as to be separated from each other.

Claims

1. A light emitting device comprising:

a semiconductor light emitting diode which comprises a first nitride semiconductor layer of an n-type, a second nitride semiconductor layer of a p-type, and a first active layer between the first and second nitride semiconductor layers; and

a nano light emitting diode array which comprises a plurality of nano light emitting diodes on the semiconductor light emitting diode.

2. The light emitting device of claim 1, wherein each of the plurality of nano light emitting diodes comprises:

a third nitride semiconductor layer of a p-type;

a fourth nitride semiconductor layer of an n-type; and

a second active layer between the third and fourth nitride semiconductor layers.

3. The light emitting device of claim 2, further comprising:

a first electrode at an end portion of the first nitride semiconductor layer;

a first transparent electrode layer on the second nitride semiconductor layer;

a second electrode at an end portion of the first transparent electrode layer;

a second transparent electrode layer on the fourth nitride semiconductor layer; and

a third electrode at an end portion of the second transparent electrode layer.

4. The light emitting device of claim 3, further comprising:

an insulation member between the first transparent electrode layer and the second transparent electrode layer.

5. The light emitting device of claim 3, wherein the first electrode and the second electrode are connected to each other, the second electrode and the third electrode are connected to each other, and the semiconductor light emitting diode and the nano light emitting diode array are configured to be independently driven.

6. The light emitting device of claim 3, wherein the first transparent electrode layer is of a p-type, and the second transparent electrode layer is of an n-type.

7. The light emitting device of claim 2, wherein the first active layer comprises an InGaN based quantum well layer configured to emit blue light, and the second active layer comprises an InGaN based quantum well layer configured to emit light of a wavelength that is mixed with the blue light to produce white light.

8. The light emitting device of claim 2, wherein the first active layer comprises an InGaN based quantum well layer configured to emit light of a first wavelength, and the second active layer comprises an InGaN based quantum well layer configured to emit light of a second wavelength that is longer than the first wavelength through a smaller bandgap than that of the first active layer.

9. The light emitting device of claim 2, wherein the first active layer comprises an InGaN based quantum well layer configured to emit blue light, and the second active layer comprises an InGaN based quantum well layer configured to emit light of a wavelength that is mixed with the blue light to produce pseudo-white light.

10. The light emitting device of claim 2, wherein the second active layer comprises an InGaN based quantum well layer configured to emit yellow light.

11. The light emitting device of claim 1, wherein each of the plurality of nano light emitting diodes has a nanorod structure.

12. The light emitting device of claim 1, wherein each of the plurality of nano light emitting diodes has a nano-pyramid structure.

13. The light emitting device of claim 2, wherein each of the plurality of nano light emitting diodes has a core-shell nanorod structure, the third nitride semiconductor layer being configured as a core nanorod and the second active layer and the fourth nitride semiconductor layer being configured as a shell around the core nanorod.

14. The light emitting device of claim 2, wherein the third and fourth nitride semiconductor layers comprise In_xAl_yGa_(1-x-y)N(0≦

x,y<

1), and the second active layer comprises In_xGa_(1-x)N(0<

x<

1).

15. The light emitting device of claim 2, wherein the first active layer and the second active layer comprise a multi-quantum well layer formed of In_xGa_(1-x)N(0<

x<

1)/In_xAl_yGa_(1-x-y)N(0≦

x,y<

1).

16. The light emitting device of claim 15, wherein the multi-quantum well layer comprises a plurality of layers having different compositions of indium (In) in the layers formed of In_xGa_(1-x)N(0<

x<

1).

17. The light emitting device of claim 1, wherein each of the plurality of nano light emitting diodes has a width in a range of about 10 nm to about 5000 nm.