Semiconductor light-emitting device and producing method for the same

1. A semiconductor light-emitting device, comprising:

a first semiconductor layer;

a light-emitting layer being disposed on the first semiconductor layer, and the light-emitting layer being lower in refractive index than the first semiconductor layer;

a second semiconductor layer being disposed on the light-emitting layer, and the second semiconductor layer being lower in refractive index than the light-emitting layer;

metal electrodes connected to the first semiconductor layer and the second semiconductor layer respectively, and the metal electrodes supplying a current to the light- emitting layer;

a light extraction portion for extracting light emitted from the light-emitting layer; and

a fluorescent substance converting a wavelength of the emitted light on the light extraction portion, the fluorescent substance disposed on the light extraction portion, wherein the light-emitting layer and the second semiconductor layer are nitride semiconductors different in aluminum concentration.

2. A semiconductor light-emitting device according to claim 1 , further comprising:

a light extraction portion having a surface roughness and extracting light emitted from the light-emitting layer.

3. A semiconductor light-emitting device according to claim 1 , wherein light emitted from the light-emitting layer is extracted from a first semiconductor layer side.

4. A semiconductor light-emitting device according to claim 3 , further comprising:

a light extraction portion having a surface roughness and extracting light emitted from the light-emitting layer.

5. A semiconductor light-emitting device according to claim 4 , further comprising:

a fluorescent substance converting a wavelength of the emitted light on the light extraction portion, the fluorescent substance disposed on the light extraction portion.

6. A semiconductor light-emitting device according to claim 1 , wherein the first semiconductor layer is an electrically conductive diamond thin film which is formed on a diamond substrate.

7. A semiconductor light-emitting device according to claim 6 , further comprising:

a light extraction portion having a surface roughness and extracting light emitted from the light-emitting layer.

8. A semiconductor light-emitting device according to claim 7 , further comprising:

a fluorescent substance converting a wavelength of the emitted light on the light extraction portion, the fluorescent substance disposed on the light extraction portion.

9. A semiconductor light-emitting device according to claim 1 , wherein the first semiconductor layer is an electrically conductive diamond substrate which is formed on a diamond substrate.

10. A semiconductor light-emitting device according to claim 9 , further comprising:

a light extraction portion having a surface roughness and extracting light emitted from the light-emitting layer.

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

a fluorescent substance converting a wavelength of the emitted light on the light extraction portion, the fluorescent substance disposed on the light extraction portion.

12. A semiconductor light-emitting device according to claim 1 , wherein the first semiconductor layer is an electrically conductive diamond thin film disposed in a substantially V-groove that is formed on the diamond substrate.

13. A semiconductor light-emitting device according to claim 12 , further comprising:

a light extraction portion having a surface roughness and extracting light emitted from the light-emitting layer.

14. A semiconductor light-emitting device according to claim 9 , wherein the light-emitting layer and the second semiconductor layer are disposed in a V-groove formed on the electrically conductive diamond substrate.

15. A method of producing a semiconductor light-emitting device, comprising:

forming a first semiconductor layer on a substrate;

forming a light-emitting layer lower in refractive index than the first semiconductor layer, on the first semiconductor layer;

forming a second semiconductor layer lower in refractive index than the light-emitting layer, on the light-emitting layer;

forming metal electrodes to be connected to the first semiconductor layer and the second semiconductor layer, the metal electrodes supplying a current to the light-emitting layer;

forming a light extraction portion for extracting light emitted from the light-emitting layer; and

forming a fluorescent substance converting a wavelength of the emitted light on the light extraction portion, the fluorescent substance disposed on the light extraction portion, wherein the first semiconductor layer, the light-emitting layer and the second semiconductor layer are formed in a V-groove formed on the substrate.

16. A method of producing a semiconductor light-emitting devices comprising:

forming a light-emitting layer lower in refractive index than an electrically conductive substrate, on a substrate;

forming a second semiconductor layer lower in refractive index than the light-emitting layer, on the light-emitting layer;

forming metal electrodes to be connected to the substrate and the second semiconductor layer respectively, and the metal electrodes supplying a current to the light-emitting layer;

forming a light extraction portion for extracting light emitted from the light-emitting layer; and

forming a fluorescent substance converting a wavelength of the emitted light on the light extraction portion, the fluorescent substance disposed on the light extraction portion, wherein the light-emitting layer and the second semiconductor layer are formed in a V-groove formed on the substrate.