LIGHT EMITTING DEVICE

• US 20100181586A1
• Filed: 10/05/2009
• Published: 07/22/2010
• Est. Priority Date: 01/21/2009
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: KIM, Sun Kyung
• Granted Patent: US 8,115,224 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• 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 33/382 the electrode extending partially in or entirely through the semiconductor body

Abstract

A light emitting device That includes a first photonic crystal structure having a reflective layer and non-metal pattern elements on the reflective layer, a second conductive semiconductor layer on both the reflective layer and the non-metal pattern elements, an active layer on the second conductive semiconductor layer, and a first conductive semiconductor layer on the active layer.

Claims

1. A light emitting device, comprising:

a first photonic crystal structure comprising a reflective layer and a plurality of non-metal pattern elements on the reflective layer;

a second conductive semiconductor layer on both the reflective layer and the non-metal pattern elements;

an active layer on the second conductive semiconductor layer; and

a first conductive semiconductor layer on the active layer.

2. The light emitting device of claim 1, further comprising:

a second electrode layer under the reflective layer; and

a first electrode layer on the first conductive semiconductor layer.

3. The light emitting device of claim 1, wherein lower and side surfaces of each of the plurality of non-metal pattern elements are surrounded by the reflective layer.

4. The light emitting device of claim 1, wherein the reflective layer comprises at least one of silver (Ag), alloy comprising Ag, aluminum (Al), and alloy comprising Al.

5. The light emitting device of claim 1, wherein the plurality of non-metal pattern elements comprise a transparent electrode.

6. The light emitting device of claim 5, wherein the transparent electrode comprises at least one of tin-doped indium oxide (ITO), zinc oxide (ZnO), gallium-doped zinc oxide (GZO), ruthenium oxide (RuO_x), and iron oxide (IrO_x).

7. The light emitting device of claim 1, wherein the plurality of non-metal pattern elements comprise a dielectric substance.

8. The light emitting device of claim 7, wherein the dielectric substance comprises at least one of silicon oxide (SiO₂), magnesium fluoride (MgF₂), titanium dioxide (TiO₂), aluminum oxide (Al₂O₃), spin on glass (SOG), and silicon nitride (Si₃N₄).

9. The light emitting device of claim 1, wherein the plurality of non-metal pattern elements are surrounded by the reflective layer and are arranged with a lattice constant in a range of λ

/n to 10λ

/n, in which λ

represents a wavelength of light emitted from the light emitting device, and n represents a refractive index of a material forming a light emitting layer of the light emitting device.

10. The light emitting device of claim 1, wherein the reflective layer is surrounded by the non-metal pattern elements so that the reflective layer is arranged with a lattice constant in a range of about λ

/n to about 10λ

/n, in which λ

represents a wavelength of light emitted from the light emitting device, and n represents a refractive index of a material forming a light emitting layer of the light emitting device.

11. The light emitting device of claim 1, wherein the non-metal pattern elements are protrusions protruding from the second conductive semiconductor layer toward the reflective layer.

12. The light emitting device of claim 1, further comprising:

a non-conductive semiconductor layer on the first conductive semiconductor layer.

13. The light emitting device of claim 1, further comprising:

a second photonic crystal structure on the first conductive semiconductor layer.

14. The light emitting device of claim 13, wherein the second photonic crystal structure comprises:

a non-conductive semiconductor layer on the first conductive semiconductor layer; and

a patterned structure on a top surface of the non-conductive semiconductor layer.

15. A light emitting device, comprising:

a reflective layer;

a transparent electrode layer comprising a plurality of protrusion pattern elements protruding from the transparent electrode layer toward the reflective layer;

a second conductive semiconductor layer on the transparent electrode layer;

an active layer on the second conductive semiconductor layer; and

a first conductive semiconductor layer on the active layer.

16. The light emitting device of claim 15, wherein lower and side surfaces of each the plurality of protrusion pattern elements is surrounded by the reflective layer.

17. The light emitting device of claim 15, wherein each of the plurality of protrusion pattern elements are surrounded by the reflective layer and are arranged with a lattice constant in a range of about λ

/n to about 10λ

/n, in which λ

represents a wavelength of light emitted from the light emitting device, and n represents a refractive index of a material forming a light emitting layer of the light emitting device.

18. The light emitting device of claim 15, wherein the reflective layer is surrounded by the protrusion pattern elements so that the reflective layer is provided with a lattice constant in a range of about λ

/n to about 10λ

/n, in which λ

represents a wavelength of light emitted from the light emitting device, and n represents a refractive index of a material forming a light emitting layer of the light emitting device.

19. The light emitting device of claim 15, further comprising:

a second electrode layer under the reflective layer; and

a first electrode layer on the first conductive semiconductor layer.

20. The light emitting device of claim 15, wherein the transparent electrode layer includes at least one material selected from the group of comprising ITO, ZnO, GZO, RuO_x, and IrO_x.

21. The light emitting device of claim 15, further comprising:

a non-conductive semiconductor layer on the first conductive semiconductor layer.

22. The light emitting device of claim 15, further comprising:

a second photonic crystal structure on the first conductive semiconductor layer.

23. The light emitting device of claim 22, wherein the second photonic crystal structure comprises:

a non-conductive semiconductor layer on the first conductive semiconductor layer; and

a patterned structure on a top surface of the non-conductive semiconductor layer.

24. A light emitting device, comprising:

a first photonic crystal structure comprising a transparent electrode layer and a plurality of reflective pattern elements on the transparent electrode layer;

a second conductive semiconductor layer on both the transparent electrode layer and the reflective pattern elements;

an active layer on the second conductive semiconductor layer; and

a first conductive semiconductor layer on the active layer.

25. The light emitting device of claim 24, further comprising:

a reflective layer under the transparent electrode layer.

26. The light emitting device of claim 24, wherein lower and side surfaces of each of the plurality of reflective pattern elements are surrounded by the transparent electrode layer.

27. The light emitting device of claim 24, further comprising:

a non-conductive semiconductor layer on the first conductive semiconductor layer.

28. The light emitting device of claim 24, further comprising:

a second photonic crystal structure 100 on the first conductive semiconductor layer.

29. The light emitting device of claim 28, wherein the second photonic crystal structure comprises:

a non-conductive semiconductor layer on the first conductive semiconductor layer; and

a patterned structure on a top surface of the non-conductive semiconductor layer.

30. The light emitting device of claim 24, further comprising:

a first electrode layer formed on the first conductive semiconductor layer.

31. A light emitting device, comprising:

a reflective layer;

a second conductive semiconductor layer on the reflective layer, the second conductive semiconductor layer including comprising a plurality of protrusion pattern elements protruding from the second conductive semiconductor layer toward the reflective layer;

an active layer on the second conductive semiconductor layer; and

a first conductive semiconductor layer 50 on the active layer.

32. The light emitting device of claim 31, wherein lower and side surfaces of each the plurality of protrusion pattern elements is surrounded by the reflective layer.

33. The light emitting device of claim 31, wherein each of the plurality of protrusion pattern elements are surrounded by the reflective layer and are arranged with a lattice constant in a range of about λ

/n to about 10λ

/n, in which λ

represents a wavelength of light emitted from the light emitting device, and n represents a refractive index of a material forming a light emitting layer of the light emitting device.

34. The light emitting device of claim 31, wherein the reflective layer is surrounded by the protrusion pattern elements so that the reflective layer is provided with a lattice constant in a range of about λ

/n to about 10λ

/n, in which λ

represents a wavelength of light emitted from the light emitting device, and n represents a refractive index of a material forming a light emitting layer of the light emitting device.

35. The light emitting device of claim 31, further comprising:

a second electrode layer under the reflective layer; and

a first electrode layer on the first conductive semiconductor layer.

36. The light emitting device of claim 31, further comprising:

a non-conductive semiconductor layer on the first conductive semiconductor layer.

37. The light emitting device of claim 31, further comprising:

a second photonic crystal structure 100 on the first conductive semiconductor layer.

38. The light emitting device of claim 37, wherein the second photonic crystal structure comprises:

a non-conductive semiconductor layer on the first conductive semiconductor layer; and

a patterned structure on a top surface of the non-conductive semiconductor layer.