Light emitting device with current blocking layer

1. A light emitting device, comprising:

a second electrode layer;

a second conductivity-type semiconductor layer on the second electrode layer;

an ohmic contact layer located between the second electrode layer and the second conductivity-type semiconductor layer;

an active layer on the second conductivity-type semiconductor layer;

a first conductivity-type semiconductor layer on the active layer;

a current blocking layer in the first conductivity-type semiconductor layer; and

a first electrode layer on the first conductivity-type semiconductor layer,

wherein the first conductivity-type semiconductor layer comprises a first nitride layer and a second nitride layer, and the first nitride layer has a smaller refractive index than the second nitride layer.

2. The light emitting device according to claim 1 , wherein at least portions of the first electrode layer, the second electrode layer, and the current blocking layer are overlapped in a vertical direction.

3. The light emitting device according to claim 1 , wherein a top surface, a bottom surface, and a side surface of the current blocking layer are surrounded by the first conductivity-type semiconductor layer.

4. The light emitting device according to claim 1 , wherein the current blocking layer is formed of at least one of SiO 2 , SiN x , TiO 2 , Ta 2 O 3 , SiON, or SiCN.

5. The light emitting device according to claim 1 , wherein the current blocking layer is provided in plurality and spaced apart from one another.

6. The light emitting device according to claim 1 , wherein the current blocking layer is formed in the second nitride layer.

7. The light emitting device according to claim 1 , wherein the first nitride layer comprises an AlGaN layer or an AlN layer, and the second nitride layer comprises a GaN layer.

8. The light emitting device according to claim 1 , wherein a bottom surface and side surfaces of the ohmic contact layer are in contact with the second electrode layer, and

wherein a top surface of the ohmic contact layer and a top surface of the second electrode layer disposed on a substantially same horizontal plane.

9. A light emitting device, comprising:

a second electrode layer;

a second conductivity-type semiconductor layer on the second electrode layer;

a contact layer having a metal material and being located between the second electrode layer and the second conductivity-type semiconductor layer, a bottom surface and side surfaces of the contact layer being in contact with the second electrode layer;

an active layer on the second conductivity-type semiconductor layer;

a first conductivity-type semiconductor layer on the active layer;

a current blocking layer in the first conductivity-type semiconductor layer; and

a first electrode layer on the first conductivity-type semiconductor layer,

wherein the current blocking layer comprises a first current blocking layer and a second current blocking layer,

the first current blocking layer and the second blocking layer are spaced apart from each other within the first conductivity-type semiconductor layer,

a portion of the first conductivity-type semiconductor layer is disposed between the first current blocking layer and the second current blocking layer, and

the first conductivity-type semiconductor layer comprises a first nitride layer and a second nitride layer, and the first nitride layer has a smaller refractive index than the second nitride layer.

10. The light emitting device according to claim 9 , wherein the first current blocking layer and the second current blocking layer are disposed on the active layer.

11. The light emitting device according to claim 9 , wherein at least portions of the first electrode layer, the second electrode layer, and the current blocking layer are overlapped in a vertical direction.

12. The light emitting device according to claim 9 , wherein a top surface, a bottom surface, and a side surface of the current blocking layer are surrounded by the first conductivity-type semiconductor layer.

13. The light emitting device according to claim 9 , wherein the current blocking layer is formed of at least one of SiO 2 , SiN x , TiO 2 , Ta 2 O 3 , SiON, or SiCN.

14. The light emitting device according to claim 9 , wherein the current blocking layer is formed in the second nitride layer.

15. The light emitting device according to claim 9 , wherein the first nitride layer comprises an AlGaN layer or an AlN layer, and the second nitride layer comprises a GaN layer.

16. A light emitting device, comprising:

a second electrode layer;

a second conductivity-type semiconductor layer on the second electrode layer;

a metallic layer located between the second electrode layer and the second conductivity-type semiconductor layer;

an active layer on the second conductivity-type semiconductor layer;

a first conductivity-type second nitride semiconductor layer on the active layer;

a first conductivity-type first nitride semiconductor layer on the first conductivity-type second nitride semiconductor layer;

a current blocking layer in the first conductivity-type second nitride semiconductor layer; and

a first electrode layer on the first conductivity-type first nitride semiconductor layer,

wherein the first conductivity-type first nitride semiconductor layer has a smaller refractive index than the first conductivity-type second nitride semiconductor layer, and

wherein an area of a top surface of the metallic layer is smaller than an area of a bottom surface of the second conductivity-type semiconductor layer.

17. The light emitting device according to claim 16 , wherein at least portions of the first electrode layer, the second electrode layer, and the current blocking layer are overlapped in a vertical direction.

18. The light emitting device according to claim 16 , wherein a top surface, a bottom surface, and a side surface of the current blocking layer are surrounded by the first conductivity-type second nitride semiconductor layer.

19. The light emitting device according to claim 16 , wherein the current blocking layer is formed of at least one of SiO 2 , SiN x , TiO 2 , Ta 2 O 3 , SiON, or SiCN.

20. The light emitting device according to claim 16 , wherein the first conductivity-type first nitride semiconductor layer comprises an AlGaN layer or an AlN layer, and the first conductivity-type second nitride semiconductor layer comprises a GaN layer.