Polarized semiconductor light emitting device

• US 20080012028A1
• Filed: 07/03/2007
• Published: 01/17/2008
• Est. Priority Date: 07/03/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Kim, Dae Yeon, Lee, Su Yeol, Yoon, Sang Ho
• Granted Patent: US 7,964,877 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: G02F 1/13362 providing polarized light, e.g. by converting a polarisation component into another one
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate

Abstract

A polarized semiconductor light emitting device includes a semiconductor structure having a first conductivity semiconductor layer, an active layer and a second conductivity semiconductor layer sequentially stacked. Also, the semiconductor structure further includes a plurality of light guide parts defined by a plurality of grooves arranged along a predetermined direction. The grooves extend from the second conductivity semiconductor layer with a depth reaching at least the active layer, and the light guide parts have a length greater than a width thereof to selectively emit a polarized component in a length direction thereof.

Claims

1. A semiconductor light emitting device comprising a semiconductor structure including a first conductivity semiconductor layer, an active layer and a second conductivity semiconductor layer sequentially stacked,

wherein the semiconductor structure further includes a plurality of light guide parts defined by a plurality of grooves arranged along a predetermined direction, the grooves extending from the second conductivity semiconductor layer with a depth reaching at least the active layer, and the light guide parts having a length greater than a width thereof to selectively emit a polarized component in a length direction thereof.

2. The semiconductor light emitting device according to claim 1, wherein the light guide parts have the length that is at least three times the width thereof.

3. The semiconductor light emitting device according to claim 1, wherein the light guide parts are formed periodically.

4. The semiconductor light emitting device according to claim 1, wherein the grooves are filled with a material having a refractivity lower than that of the semiconductor structure.

5. The semiconductor light emitting device according to claim 1, further comprising an insulating substrate having the first conductivity semiconductor layer, the active layer and the second conductivity semiconductor layer sequentially stacked thereon,

wherein the semiconductor structure is mesa-etched to expose a portion of the first conductivity semiconductor layer, and further includes a first electrode formed on an exposed portion of the first conductivity semiconductor layer and a second electrode formed on a portion of the second conductivity semiconductor layer.

6. The semiconductor light emitting device according to claim 5, wherein each of the grooves is extended toward the first electrode from a position adjacent to the second electrode.

7. The semiconductor light emitting device according to claim 1, further comprising:

a conductive substrate having the second semiconductor layer, the active layer and the first conductivity semiconductor layer sequentially stacked thereon;

a first electrode formed on a portion of the first conductivity substrate; and

a second electrode formed underneath the conductive substrate.

8. The semiconductor light emitting device according to claim 7, wherein the grooves are extended from an edge of the semiconductor structure to an opposing edge thereof.

9. The semiconductor light emitting device according to claim 1, wherein the grooves are arranged in at least two rows.

10. The semiconductor light emitting device according to claim 9, wherein the light guide parts are connected with one another by the second conductivity layer.

11. The semiconductor light emitting device according to claim 1, wherein the semiconductor structure comprises first and second reflective layers having the active layer interposed therebetween, the first and second reflective layers formed at an interval corresponding to natural number times a half wavelength of light generated from the active layer,

wherein the second reflective layer is disposed in a light exiting direction and the second reflective layer has a lower refractivity for a wavelength of light generated from the active layer than that generated from the first reflective layer.

12. The semiconductor light emitting device according to claim 11, wherein the first reflective layer has at least 80% reflectivity for the wavelength of light generated from the active layer, and the second reflective layer has 20% to 60% reflectivity for the wavelength of light generated from the active layer.

13. The semiconductor light emitting device according to claim 11, further comprising an insulating substrate having the first conductivity semiconductor layer, the active layer and the second conductivity semiconductor layer sequentially stacked thereon,

wherein the second reflective layer is disposed on the second conductivity semiconductor layer, and the first reflective layer is disposed inside the first conductivity semiconductor layer.

14. The semiconductor light emitting device according to claim 11, further comprising a conductive substrate having the second conductivity semiconductor layer, the active layer and the first conductivity semiconductor layer sequentially stacked thereon,

wherein the first reflective layer is disposed inside the first conductivity semiconductor layer, and the second reflective layer comprises the conductive substrate or a metal reflective layer interposed between the conductive substrate and the first conductivity semiconductor layer.

15. The semiconductor light emitting device according to claim 13, wherein the first reflective layer comprises a Distributed-Bragg Reflector (DBR) structure in which semiconductor layers of different refractivity are stacked alternately at least once.

16. The semiconductor light emitting device according to claim 12, wherein the first reflective layer comprises a Distributed-Bragg Reflector (DBR) structure in which semiconductor layers of different refractivity are stacked alternately at least once.