SEMICONDUCTOR LIGHT-EMITTING DEVICE

• US 20100148203A1
• Filed: 12/15/2009
• Published: 06/17/2010
• Est. Priority Date: 12/17/2008
• Status: Active Grant

• Current Assignee: Alpad Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Hwang, Jongil, Sato, Takahiro, Nunoue, Shinya, Hattori, Yasushi, Harada, Yoshiyuki, Saito, Shinji, Sugai, Maki, HASHIMOTO, Rei
• Granted Patent: US 7,985,981 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/644 in intimate contact or integrated with parts of the device other than the semiconductor body
• CPC Class Codes: H01S 5/0087 for illuminating phosphorescent or fluorescent materials, e.g. using optical arrangements specifically adapted for guiding or shaping laser beams illuminating these materials
• CPC Class Codes: H01S 5/02255 using beam deflecting elements
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

There is provided a semiconductor light-emitting device including a semiconductor light-emitting element, a phosphor layer disposed in a light path of a light emitted from the semiconductor light-emitting element, containing a phosphor to be excited by the light and having a cross-section in a region of a diameter which is 1 mm larger than that of a cross-section of the light path, and a heat-releasing member disposed in contact with at least a portion of the phosphor layer and exhibiting a higher thermal conductance than that of the phosphor layer.

Claims

1. A semiconductor light-emitting device comprising:

a semiconductor light-emitting element;

a phosphor layer disposed in a light path of a light emitted from the semiconductor light-emitting element, containing a phosphor to be excited by the light and having a cross-section in a region of a diameter which is 1 mm larger than that of a cross-section of the light path; and

a heat-releasing member disposed in contact with at least a portion of the phosphor layer and exhibiting a higher thermal conductance than that of the phosphor layer.

2. The device according to claim 1, wherein the phosphor layer has a cross-section in a region of the cross-section of the light path.

3. The device according to claim 1, wherein the semiconductor light-emitting element is a semiconductor laser.

4. The device according to claim 1, wherein the semiconductor light-emitting element is a high-output semiconductor light-emitting diode.

5. The device according to claim 1, which is provided with a plurality of the semiconductor light-emitting elements.

6. The device according to claim 1, wherein the phosphor layer is arranged at a position apart from the semiconductor light-emitting element, where maximum density of light emitted from the semiconductor light-emitting element is not more than 1000 mW/mm².

7. The device according to claim 1, wherein the semiconductor light-emitting element is formed of a III-Group nitride compound semiconductor.

8. The device according to claim 1, wherein at least a portion of the light emitted from the phosphor layer is visible light.

9. The device according to claim 1, wherein the heat-releasing member is formed of metal.

10. The device according to claim 1, wherein the phosphor layer has a volume concentration distribution of the phosphor which is higher in a region distal to the semiconductor light-emitting element and is lower in a region proximal to the semiconductor light-emitting element.

11. The device according to claim 8, wherein a layer containing no phosphor is disposed in a region of the light path which is located not more than 1 mm away from a light-emitting face of the semiconductor light-emitting element.

12. The device according to claim 1, wherein a base material of the phosphor layer is formed of a material selected from the group consisting of a transparent resin, glass, a sintered body and a ceramic material.

13. The device according to claim 1, wherein the phosphor is formed of a material selected from the group consisting of a silicate-based fluorescent material, an aluminate-based fluorescent material, a nitride-based fluorescent material, a sulfide-based fluorescent material, an oxysulfide-based fluorescent material, a YAG-based fluorescent material, a phosphate-based fluorescent material, a borate-based fluorescent material, and a halo-phosphate-based fluorescent material.

14. The device according to claim 1, wherein the phosphor is formed of a material selected from the group consisting of a blue light-emitting fluorescent material, a yellow light-emitting fluorescent material, a green light-emitting fluorescent material, a red light-emitting fluorescent material and a white light-emitting fluorescent material.

15. The device according to claim 1, wherein the phosphor layer has a columnar shape elongated along the light path.

16. The device according to claim 1, wherein the phosphor layer has a shape similar to the light path and has a long cone-shape extending along the light path.

17. The device according to claim 1, wherein the phosphor layer has a light incident surface of a convex shape.

18. The device according to claim 1, wherein a layer formed of a material exhibiting a smaller refractive index than that of the phosphor layer is interposed between the semiconductor light-emitting element and the phosphor layer.

19. The device according to claim 1, further comprising a rectangular parallelepiped housing having a wall, in which the semiconductor light-emitting element is arranged, wherein a portion of the wall which faces the light-emitting face of the semiconductor light-emitting element is formed of the heat-releasing member, the wall has a slit in a light incident region, and the phosphor layer is arranged in the slit.