Optical semiconductor device and method for manufacturing the same

1. A semiconductor light-emitting device comprising:

a silicon substrate;

a first light reflection structure provided in contact with the silicon substrate;

a buried layer made of silicon, being in contact with the silicon substrate, and surrounding the first light reflection structure;

an optical semiconductor structure including an active layer, provided above the first light reflection structure;

a second light reflection structure provided above the optical semiconductor structure; and

a pair of electrodes which supply current to the optical semiconductor structure,

wherein a surface of the first light reflection structure and a surface of the buried layer are included in the same plane, and

a bottom layer of the optical semiconductor structure is in contact with the first light reflection structure and the buried layer.

2. The semiconductor light-emitting device according to claim 1 , wherein one or both of the first and second light reflection structures include a structural layer whose refractive index changes periodically in its in-plane direction.

3. The semiconductor light-emitting device according to claim 1 , wherein a semiconductor material of the optical semiconductor structure is different from the silicon substrate.

4. The semiconductor light-emitting device according to claim 1 , wherein the active layer is narrower than the first light reflection structure.

5. The semiconductor light-emitting device according to claim 1 , wherein the active layer is wider than the first light reflection structure.

6. The semiconductor light-emitting device according to claim 1 , wherein the active layer is surrounded by an ion-implanted semiconductor.

7. The semiconductor light-emitting device according to claim 1 , wherein the optical semiconductor structure comprises Group III-V compound semiconductor.

8. The semiconductor light-emitting device according to claim 1 , further comprising a metal layer as an upper layer of the second light reflection structure, the metal layer doubling as one of the electrodes.

9. The semiconductor light-emitting device according to claim 1 , wherein the first light reflection structure further comprises a transparent electrode, and a metal layer is provided on the substrate, surrounding the transparent electrode to electrically connect with the transparent electrode.

10. The semiconductor light-emitting device according to claim 1 , wherein the first light reflection structure further comprises a metal grid electrode.

11. The semiconductor light-emitting device according to claim 1 , wherein a heat-dissipating metal is buried in the substrate, surrounding a region corresponding to the first light reflection structure.

12. The semiconductor light-emitting device according to claim 1 , further comprising a thermally conductive dielectric layer between the substrate and the first light reflection structure, and/or between the first light reflection structure and the optical semiconductor structure.

13. The semiconductor light-emitting device according to claim 6 , wherein the optical semiconductor structure includes a current constriction structure, and the current constriction structure is constituted by a current constriction layer provided in the optical semiconductor structure and including high resistance regions having relatively high electrical resistance and low resistance regions having relatively low electrical resistance, wherein the high and low resistance regions are arranged in a period corresponding to the period in the second structural layer, and one of the electrodes is in contact with a portion of a surface of the current constriction structure.

14. The semiconductor light-emitting device according to claim 1 , wherein the second light reflection structure has an optical reflectance higher than that of the first light reflection structure.

15. An optical semiconductor device comprising:

one silicon substrate, and

a semiconductor light-emitting device and a light-receiving device, which are provided on the silicon substrate,

wherein the semiconductor light-emitting device comprises a first light reflection structure provided in contact with the silicon substrate, a buried layer made of silicon, being in contact with the silicon substrate, and surrounding the first light reflection structure, an optical semiconductor structure including an active layer, provided above the first light reflection structure, a second light reflection structure provided above the optical semiconductor structure, and a pair of electrodes which supply current to the optical semiconductor structure, wherein a surface of the first light reflection structure and a surface of the buried layer are included in the same plane, and a bottom layer of the optical semiconductor structure is in contact with the first light reflection structure and the buried layer,

the semiconductor light-receiving device comprises an optical semiconductor structure including an active layer, provided on the silicon substrate, a first structural layer which is provided between the silicon substrate and the optical semiconductor structure, in which refractive index changes periodically and into which light is incident from a side of the substrate, a light reflection structure comprising a second structural layer whose refractive index changes periodically, provided above the optical semiconductor structure, and a pair of electrodes which apply a voltage to the optical semiconductor structure, and

the optical semiconductor structure in the semiconductor light-emitting device and the optical semiconductor structure in the semiconductor light-receiving device have the same layer construction and are formed of the same semiconductor material.

16. The semiconductor light-emitting device according to claim 15 , wherein the second light reflection structure has an optical reflectance higher than that of the first light reflection structure.