Led Chip

• US 20110114988A1
• Filed: 04/28/2009
• Published: 05/19/2011
• Est. Priority Date: 04/30/2008
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Weimar, Andreas, Baur, Johannes, Sabathil, Matthias, Hoeppel, Lutz, Engl, Karl
• Granted Patent: US 8,530,923 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/641 characterized by the materials
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

A light-emitting diode chip (1) with a semiconductor layer sequence (2) is described, which is contacted electrically by contacts (5) via a current spreading layer (3). The contacts (5) cover around 1%-8% of the surface of the semiconductor layer sequence (2). The contacts (5) consist for example of separate contact points (51), which are arranged at the nodes of a regular grid (52) with a grid constant of 12 μm. The current spreading layer (3) contains for example indium-tin oxide, indium-zinc oxide or zinc oxide and has a thickness in the range from 15 nm to 60 nm.

Claims

1. A light-emitting diode chip with a semiconductor layer sequence, which comprises an active zone for generating electromagnetic radiation, with a current spreading layer, which adjoins the semiconductor layer sequence, with contacts, which electrically contact the current spreading layer, wherein the contacts cover between at least 1% and at most 8% of the surface of the current spreading layer.

2. The light-emitting diode chip according to claim 1, wherein the thermal conductivity of the contacts increases with increasing distance from the semiconductor layer sequence.

3. The light-emitting diode chip according to claim 1, wherein the cross-sectional areas of the contacts increase with increasing distance from the semiconductor layer sequence.

4. The light-emitting diode chip according to claim 1, wherein the thermal conductivity of the contacts increases with increasing distance from the semiconductor layer sequence, and wherein the cross-sectional areas of the contacts increase with increasing distance from the semiconductor layer sequence.

5. The light-emitting diode chip according to claim 1 wherein the contacts are conical in form.

6. The light-emitting diode chip according to claim 1, wherein the contacts are distributed uniformly over the surface of the current spreading layer.

7. The light-emitting diode chip according to claim 1, wherein the spacing of neighbouring contacts is less than 30 μ

m.

8. The light-emitting diode chip according to claim 1, wherein the contacts consist of separate contact points.

9. The light-emitting diode chip according to claim 1, wherein the contacts are arranged at nodes of a regular grid.

10. The light-emitting diode chip according to claim 1, wherein the current spreading layer comprises a thickness in the range from at least 10 nm to at most 60 nm.

11. The light-emitting diode chip according to claim 1, wherein the current spreading layer contains indium-zinc oxide and has a thickness of at least 15 nm.

12. The light-emitting diode chip according to claim 1, wherein the current spreading layer contains indium-tin oxide and has a thickness of at least 30 nm.

13. The light-emitting diode chip according to claim 1, wherein the current spreading layer contains zinc oxide and has a thickness of at least 40 nm.

14. The light-emitting diode chip according to claim 1, wherein the contacts pass through a dielectric layer, in particular an air layer.

15. The light-emitting diode chip according to claim 1, wherein the contacts are connected electrically with a metallic layer, which closes off the dielectric layer in the direction of a carrier.

16. The light-emitting diode chip according to claim 14, wherein said dielectric layer is an air layer.