Nitride semiconductor light emitting device and manufacturing method of the same

1 . A nitride semiconductor light emitting device comprising:

a substrate for growing a nitride single crystal, the substrate having electrical conductivity;

a p-type nitride semiconductor layer formed on the substrate;

an active layer formed on the p-type nitride semiconductor layer, the active layer comprising a plurality of quantum barrier layers and a plurality of quantum well layers deposited alternately on each other;

an n-type nitride semiconductor layer formed on the active layer;

a p-electrode formed on a bottom of the substrate; and

an n-electrode formed on a top of the n-type nitride semiconductor layer.

2 . The nitride semiconductor light emitting device of claim 1 , wherein the substrate is a p-type GaN substrate.

3 . The nitride semiconductor light emitting device of claim 2 , wherein the p-type GaN substrate has a doping concentration of 1×10 17 to 9×10 19 /cm 3 .

4 . The nitride semiconductor light emitting device of claim 2 , wherein the p-type GaN substrate has a thickness of about 50 to 100 nm.

5 . The nitride semiconductor light emitting device of claim 1 , wherein the p-type nitride semiconductor layer comprises a p-type AlGaN layer formed on the substrate to have an interface contacting the active layer.

6 . The nitride semiconductor light emitting device of claim 5 , wherein the p-type nitride semiconductor layer comprises a p-type GaN layer formed on an interface contacting a top of the substrate.

7 . The nitride semiconductor light emitting device of claim 5 , wherein among the quantum barrier layers, a quantum barrier layer having an interface contacting the p-type AlGaN layer is formed of an undoped GaN layer.

8 . The nitride semiconductor light emitting device of claim 7 , wherein the undoped GaN layer has a thickness of 2 to 10 nm.

9 . The nitride semiconductor light emitting device of claim 1 , wherein the n-type nitride semiconductor layer is formed of n-type GaN.

10 . The nitride semiconductor light emitting device of claim 1 , wherein the n-type nitride semiconductor layer has a thickness of 2 to 500 nm.

11 . The nitride semiconductor light emitting device of claim 1 , further comprising a reflective metal layer formed between the substrate and the p-electrode.

12 . A method of manufacturing a nitride semiconductor light emitting device, the method comprising:

providing a substrate for growing a nitride single crystal, the substrate having electrical conductivity;

growing a p-type nitride semiconductor layer on the substrate;

growing an active layer on the p-type nitride semiconductor layer, the active layer comprising a plurality of quantum barrier layers and a plurality of quantum well layers deposited alternately on each other;

growing an n-type nitride semiconductor layer on the active layer;

forming a p-electrode on a bottom of the substrate; and

forming an n-electrode on a top of the n-type nitride semiconductor layer.

13 . The method of claim 12 , wherein the substrate is a p-type GaN substrate.

14 . The method of claim 13 , wherein the p-type GaN substrate has a doping concentration of 1×10 17 to 9×10 19 /cm 3 .

15 . The method of claim 13 , wherein the p-type GaN substrate has a thickness of about 50 to 100 nm.

16 . The method of claim 12 , wherein the p-type nitride semiconductor layer comprises a p-type AlGaN layer formed on the substrate to have an interface contacting the active layer.

17 . The method of claim 16 , wherein the p-type nitride semiconductor layer comprises a p-type GaN layer formed on an interface contacting a top of the substrate.

18 . The method of claim 16 , wherein among the quantum barrier layers, a quantum barrier layer having an interface contacting the p-type AlGaN layer is formed of an undoped GaN layer.

19 . The method of claim 18 , wherein the undoped GaN layer has a thickness of 2 to 10 nm.

20 . The method of claim 12 , wherein the n-type nitride semiconductor layer is formed of n-type GaN.

21 . The method of claim 12 , wherein the n-type nitride semiconductor layer has a thickness of 2 to 500 nm.

22 . The method of claim 12 , further comprising: forming a reflective metal layer between the substrate and the p-electrode.

23 . The method of claim 12 , wherein the p-type nitride semiconductor layer is grown at a temperature of 950° C. or higher.

24 . The method of claim 12 , wherein the p-type nitride semiconductor layer is grown at a temperature of 1000 to 1200° C.

25 . The method of claim 12 , wherein the un-doped GaN layer is grown at a temperature of 950° C. or higher.

26 . The method of claim 12 , wherein the p-type nitride semiconductor layer is directly heat-treated in a reactor.

27 . The method of claim 12 , further comprising: polishing the substrate after all of the layers are grown.

28 . The method of claim 12 , wherein the polishing the substrate is performed after the forming an n-electrode and before the forming a p-electrode.