Semiconductor light emitting device

• US 8,698,174 B2
• Filed: 04/13/2007
• Issued: 04/15/2014
• Est. Priority Date: 04/13/2006
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: Hsieh, Min-Hsun
• Primary Examiner(s): Tran, Long K
• Assistant Examiner(s): KLEIN, JORDAN M
• Application Number:
  US11/785,124
• Publication Number:
  US 20070241356A1
• Time in Patent Office: 2,559 Days
• Field of Search: 257/13, 257/79, 257/80, 257/81, 257/82, 257/98, 257/95, 257/E33.071, 257/E33.072
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

This invention relates to a semiconductor light-emitting device including a semiconductor light-emitting chip and a transparent carrier. The semiconductor light-emitting chip includes an active layer and transparent substrate. The active layer emits light under a bias. At least a portion of the light emitted from the active layer enters into the transparent carrier through the transparent substrate. The semiconductor light-emitting chip is coupled to the transparent carrier through the transparent substrate. The area of the transparent carrier is larger than that of the active layer.

Claims

1. A semiconductor light-emitting device, comprising:

a light-emitting structure comprising an active layer capable of emitting light and located between a first type semiconductor layer and a second type semiconductor layer, and a transparent substrate on the first type semiconductor layer, having a first surface and a second surface opposite to the first surface, wherein the first surface is closer to the active layer than the second surface;

a transparent carrier located on the second surface of the transparent substrate for carrying the light-emitting structure and distinguishing from the light-emitting structure, having a third surface and a fourth surface opposite to the third surface, wherein the third surface is closer to the active layer than the fourth surface, wherein light emitting from the active layer is capable of escaping from a lateral surface of the transparent carrier; and

a reflection layer located on the fourth surface;

wherein the light-emitting structure is projected from the transparent carrier, the area of the third surface is not less than each area of the first surface and the second surface and an area ratio of the fourth surface to the active layer is between 4 and 8.

2. The semiconductor light-emitting device according to claim 1, wherein the transparent substrate is attached to the first type semiconductor layer or the second type semiconductor layer by a material transparent relative to the light from the active layer.

3. The semiconductor light-emitting device according to claim 1, wherein the area of the first surface is not less than that of the active layer, and the area of the second surface is not less than that of the active layer.

4. The semiconductor light-emitting device according to claim 1, wherein the area of the fourth surface is greater than that of the third surface, the area of the third surface is greater than that of the second surface, and the area of the second surface is greater than that of the first surface.

5. The semiconductor light-emitting device according to claim 1, wherein the area of the second surface is greater than that of the first surface, the area of the fourth surface is greater than that of the third surface, and the area of the second surface and the third surface are essentially the same.

6. The semiconductor light-emitting device according to claim 1, wherein a portion of the third surface uncovered by the light-emitting structure comprises an uneven surface.

7. The semiconductor light-emitting device according to claim 1, wherein a portion of the third surface uncovered by the light-emitting structure comprises a rough surface.

8. The semiconductor light-emitting device according to claim 1, wherein the light-emitting structure further comprises two electrodes located on the same side and electrically connecting to the first type semiconductor layer and the second type semiconductor layer.

9. The semiconductor light-emitting device according to claim 8, wherein a surface of the light-emitting structure, adjacent to and uncovered by the electrodes, comprises an uneven surface.

10. The semiconductor light-emitting device according to claim 8, wherein a surface of the light-emitting structure, adjacent to and uncovered by the electrodes, comprises a rough surface.

11. The semiconductor light-emitting device according to claim 1, wherein the transparent carrier is a frustum.

12. The semiconductor light-emitting device according to claim 1, wherein the transparent carrier comprises a lateral cambered surface.

13. The semiconductor light-emitting device according to claim 1, wherein a difference between the thermal expansion coefficient of the transparent substrate and that of the transparent carrier is not greater than 1×

10<sup>−

5</sup>/°

C.

14. The semiconductor light-emitting device according to claim 1, wherein materials of the transparent substrate are selected from the group consisting of sapphire, SiC, GaP, GaAsP, ZnSe, and CVD diamond.

15. The semiconductor light-emitting device according to claim 1, wherein materials of the transparent carrier are selected from the group consisting of sapphire, SiC, GaP, GaAsP, ZnSe, diamond and CVD diamond.

16. The semiconductor light-emitting device according to claim 1, wherein the size of the transparent carrier is larger than or equal to 14 mil and smaller than or equal to 40 mil.

17. The semiconductor light-emitting device according to claim 1, wherein the thickness of the transparent carrier is about 120 μ

m.

18. The semiconductor light-emitting device according to claim 1, further comprising a base coupled to the transparent carrier, and a space formed between the transparent carrier and the base.

19. A backlight module, comprising:

a light-emitting structure comprising an active layer capable of emitting light and located between a first type semiconductor layer and a second type semiconductor layer and a transparent substrate located on the first type semiconductor layer, having a first surface and a second surface opposite to the first surface, wherein the first surface is closer to the active layer than the second surface;

a transparent carrier located on the second surface of the transparent substrate for carrying the light-emitting structure and distinguishing from the light-emitting structure, having a third surface and a fourth surface opposite to the first surface, wherein the third surface is closer to the active layer than the fourth surface, wherein light emitting from the active layer is capable of escaping from a lateral surface of the transparent carrier;

a reflection layer located on one side of the transparent carrier opposite to the light-emitting structure;

a base coupled to the transparent carrier;

an anode support connected to the base; and

a cathode support connected to the base;

wherein the transparent substrate is attached to the transparent carrier by a material transparent relative to light from the active layer;

wherein the area of the third surface is not less than each area of the first surface and the second surface, and the area ratio of the fourth surface to the active layer is between 4 and 8;

wherein an anode and a cathode of the light-emitting structure are electrically connected to the anode support and the cathode support.

20. The semiconductor light-emitting device according to claim 19, wherein the transparent carrier comprises at least a surface closer to the base than the light-emitting structure.