Semiconductor light emitting device and method of manufacturing the same

1. A semiconductor light emitting device, comprising:

a first conductive semiconductor layer comprising a concave or convex portion;

an active layer on the first conductive semiconductor layer; and

a second conductive semiconductor layer on the active layer;

wherein the first conductive semiconductor layer comprises:

a second nitride-based semiconductor layer under the active layer, and

a first nitride-based semiconductor layer comprising the concave or convex portion under the second nitride-based semiconductor layer,

wherein the second nitride-based semiconductor layer has a different material than the first nitride-based semiconductor layer which contains an aluminum (Al) material, and

wherein the first nitride-based semiconductor layer has a refractive index less than that of the second nitride-based semiconductor layer.

2. The semiconductor light emitting device according to claim 1 , wherein the concave or convex portion is formed in a lens shape or a hemispherical shape having a predetermined curvature.

3. The semiconductor light emitting device according to claim 1 , wherein a section of the concave or convex portion is formed in one of a circular shape, a polygonal shape, an irregular shape, and a pipe shape.

4. The semiconductor light emitting device according to claim 1 , wherein the concave or convex portion is disposed with a predetermined depth from a top surface of the first nitride-based semiconductor layer.

5. The semiconductor light emitting device according to claim 1 , further comprising:

at least one of an undoped layer, a buffer layer, and a substrate disposed under the first conductive semiconductor layer; and

at least one of an n-type semiconductor layer, a transparent electrode, and a second electrode disposed on the second conductive semiconductor layer.

6. The semiconductor light emitting device according to claim 1 ,

Wherein each of the first and second nitride-based semiconductor layers includes an n-type semiconductor layer, and

wherein at least one concave or convex portion is formed on a boundary surface of the n-type semiconductor layer.

7. The semiconductor light emitting device according to claim 1 , further comprising:

a first electrode directly contacted with a lower surface of the first conductive semiconductor layer;

a reflective electrode layer on the second conductive semiconductor layer; and

a conductive supporting member on the reflective electrode layer.

8. The semiconductor light emitting device according to claim 1 , wherein the concave or convex portion comprises a conductive or non-conductive material.

9. The semiconductor light emitting device according to claim 1 , further comprising:

a first electrode on the first conductive semiconductor layer; and

a second electrode on the second conductive semiconductor layer,

wherein the second nitride-based semiconductor layer includes a stepped structure having a second top surface stepped lower than a first top surface thereof,

wherein the first electrode contacts with the second top surface of the second nitride-based semiconductor layer, and

wherein the concave or convex portion faces to the first electrode with respect to a thickness direction of the second nitride-based semiconductor layer.

10. A semiconductor light emitting device, comprising:

a plurality of first conductive semiconductor layers;

a plurality of concave or convex lens portions disposed between the plurality of first conductive semiconductor layers;

an active layer on the plurality of first conductive semiconductor layers; and

at least one conductive semiconductor layer on the active layer,

wherein the plurality of first conductive semiconductor layers comprises:

a second nitride-based semiconductor layer under the active layer, and

a first nitride-based semiconductor layer comprising the plurality of concave or convex lens portions under the second nitride-based semiconductor layer,

wherein the first nitride-based semiconductor layer has a refractive index less than that of the second nitride-based semiconductor layer, and

wherein an amount of aluminum (Al) material contained in the first nitride-based semiconductor layer is greater than an amount of aluminum (Al) material contained in the second nitride-based semiconductor layer.

11. The semiconductor light emitting device according to claim 10 , further comprising:

a first electrode under the plurality of first conductive semiconductor layers;

a reflective electrode layer on the at least one conductive semiconductor layer; and

a conductive supporting member on the reflective electrode layer,

wherein the at least one conductive semiconductor layer is a p-type semiconductor layer.

12. The semiconductor light emitting device according to claim 10 ,

wherein a top surface of the first nitride-based semiconductor layer is disposed on a same plane with a top surface of the plurality of concave or convex lens portions, and

wherein the plurality concave or convex lens portions comprises at least one of SiO 2 , ITO, Al 2 O 3 , and Si.

13. The semiconductor light emitting device according to claim 10 , wherein each of the plurality of concave or convex lens portions has a height of 0.01-50 μm and a width of 0.01-1000 μm.

14. The semiconductor light emitting device according to claim 10 ,

wherein the first nitride-based semiconductor layer is thicker than the second nitride-based semiconductor layer.

15. The semiconductor light emitting device according to claim 10 , further comprising:

a substrate under the plurality of first conductive semiconductor layers; and

a plurality of convex lens portions protrude from a top surface of the substrate.

16. The semiconductor light emitting device according to claim 8 , further comprising a first electrode on the first conductive semiconductor layer,

wherein the second nitride-based semiconductor layer includes a stepped structure having a second top surface stepped lower than a first top surface thereof,

wherein the first electrode contacts with the second top surface of the second nitride-based semiconductor layer, and

wherein the concave or convex portion faces to the first electrode with respect to a thickness direction of the second nitride-based semiconductor layer.

17. The semiconductor light emitting device according to claim 9 ,

wherein the concave or convex portion comprises at least one of SiO 2 , ITO, Al 2 O 3 , and Si, and

wherein the first nitride-based semiconductor layer is a AlGaN layer or GaN layer and the second nitride-based semiconductor layer is a GaN layer or InGaN layer.

18. The semiconductor light emitting device according to claim 12 , further comprising:

a first electrode directly contacted with a lower surface of the first nitride-based semiconductor layer;

a reflective electrode layer on the at least one conductive semiconductor layer; and

a conductive supporting member on the reflective electrode layer.