Light-emitting diode chip including a mirror layer and a light-generating active zone

• US 7,709,851 B2
• Filed: 04/14/2005
• Issued: 05/04/2010
• Est. Priority Date: 04/14/2004
• Status: Active Grant

• Current Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Bader, Stefan, Schmid, Wolfgang
• Primary Examiner(s): Soward; Ida M
• Application Number:
  US11/578,657
• Publication Number:
  US 20080142780A1
• Time in Patent Office: 1,846 Days
• Field of Search: 257/13, 257 81- 82, 257/99, 257433-434, 257/98, 257/E33.001
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/405 Reflective materials
• CPC Class Codes: H01L 33/465 with a resonant cavity structure

Abstract

A thin-film light-emitting diode chip, in which the distance between a mirror layer (4) and a light-generating active zone (3) is set in such a way that a radiation emitted by the active zone (3) interferes with a light reflected from the mirror layer (4), the internal quantum efficiency of the active zone (3) being influenced by this interference and the emission characteristic of the active zone (3) of at least one preferred direction thereby being obtained.

Claims

1. A thin-film light-emitting diode chip, comprising:

a mirror layer;

a light generating active zone configured for generating light at a wavelength λ

; and

a semiconducting radiation coupling-out area,

wherein the light-generating active zone is arranged between the mirror layer and the semiconductor radiation coupling-out area, and

wherein the distance between said mirror layer and said light-generating active zone is one of between 0.16λ and

0.28λ

, and between 0.63λ and

0.78λ

, and between 1.15λ and

1.38λ

.

2. The thin-film light-emitting diode chip as claimed in claim 1, wherein the distance between the mirror layer and the active zone is less than 2λ

.

3. The thin-film light-emitting diode chip as claimed in claim 1, wherein the semiconductor body comprises GaN or GaN compounds.

4. The thin-film light-emitting diode chip as claimed in claim 1, wherein the mirror layer effects broadband reflection.

5. The thin-film light-emitting diode chip as claimed in claim 4, wherein the mirror layer comprises a metal layer.

6. The thin-film light-emitting diode chip as claimed in claim 1, further comprising a carrier facing the mirror layer, wherein said carrier is not a growth substrate for the semiconductor body.

7. The thin-film light-emitting diode chip as claimed in claim 6, further comprising at least one adhesion promoting layer disposed between the mirror layer and the carrier.

8. The thin-film light-emitting diode chip as claimed in claim 6, wherein the carrier is electrically conductive and the first semiconductor layer is contact-connected by means of said carrier.

9. The thin-film light-emitting diode chip as claimed in claim 1, further comprising a semiconductor body comprising the active zone and the coupling-out layer.

10. The thin-film light-emitting diode chip as claimed in claim 9, wherein the semiconductor body comprises a planar coupling-out area.

11. The thin-film light-emitting diode chip as claimed in claim 9, wherein the semiconductor body comprises a roughened coupling-out area.

12. The thin-film light-emitting diode chip as claimed in claim 9, wherein the light-emitting diode chip does not comprise a resonator.

13. The thin-film light-emitting diode chip as claimed in claim 12, wherein the second semiconductor layer is arranged between the active zone and an antireflection coating layer.

14. The thin-film light-emitting diode chip as claimed in claim 9, wherein the active zone is arranged between a first semiconductor layer of a first conductivity type and a second semiconductor layer of a second conductivity type, the second semiconductor layer forms a coupling-out layer, and the first semiconductor layer is arranged between the mirror layer and the active zone.

15. The thin-film light-emitting diode chip as claimed in claim 14, wherein the distance between the mirror layer and the active zone is equal to the thickness of the first semiconductor layer.

16. A thin-film light-emitting diode chip, comprising:

a mirror layer;

a light generating active zone configured for generating light at a wavelength λ

; and

a semiconducting radiation coupling-out area,

wherein the light-generating active zone is arranged between the mirror layer and the semiconductor radiation coupling-out area, and

wherein the distance between said mirror layer and said light-generating active zone is one of between 0.16λ and

0.28λ

, and between 0.63λ and

0.78λ

, and between 1.15λ and

1.38λ

, and wherein the wavelength λ

is in one of the infrared range, visible range and ultraviolet range.

17. A thin-film light-emitting diode chip, comprising:

a mirror layer;

a light generating active zone configured for generating light at a wavelength λ

; and

a semiconducting radiation coupling-out area,

wherein the light-generating active zone is arranged between the mirror layer and the semiconductor radiation coupling-out area, and

wherein the distance between said mirror layer and said light-generating active zone is one of between 0.16λ and

0.28λ

, and between 0.63λ and

0.78λ

, and between 1.15λ and

1.38λ

, and wherein the distance between said mirror layer and said light-generating active zone is constant for the length of a side of said mirror layer facing said light-generating active zone.