LIGHT-EMITTING DIODES

• US 20150041834A1
• Filed: 10/16/2014
• Published: 02/12/2015
• Est. Priority Date: 07/07/2010
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Reill, Joachim, Bogner, Georg, Grtsch, Stefan
• Granted Patent: US 9,431,378 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/13 the devices being of a type provided for in group H01L33/00
• 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 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/644 in intimate contact or integrated with parts of the device other than the semiconductor body
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/05 Insulated conductive substrates, e.g. insulated metal substrate
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 2201/10409 Screws
• CPC Class Codes: H05K 3/445 having insulated holes or insulated via connections through the metal core

Abstract

A light-emitting diode includes a carrier including a metallic basic body having an outer face including a mounting face; and at least two light-emitting diode chips affixed to the carrier at least indirectly at the mounting face, wherein the at least two light-emitting diode chips are embedded in a reflective coating covering the mounting face and side faces of the at least two light-emitting diode chips, the at least two light-emitting diode chips have radiation exit surfaces facing away from the carrier, and the at least two light-emitting diode chips protrude with radiation exit surfaces out of the reflective coating, or the reflective coating terminates flush with the radiation exit surfaces of the at least two light-emitting diode chips.

Claims

1. A light-emitting diode comprising:

a carrier comprising a metallic basic body having an outer face comprising a mounting face; and

at least two light-emitting diode chips affixed to the carrier at least indirectly at the mounting face,

wherein the at least two light-emitting diode chips are embedded in a reflective coating covering the mounting face and side faces of the at least two light-emitting diode chips,

the at least two light-emitting diode chips have radiation exit surfaces facing away from the carrier, and

the at least two light-emitting diode chips protrude with radiation exit surfaces out of the reflective coating, or the reflective coating terminates flush with the radiation exit surfaces of the at least two light-emitting diode chips.

2. The light-emitting diode according to claim 1, wherein the reflective coating completely covers the mounting face at its exposed regions.

3. The light-emitting diode according to claim 1, wherein all exposed regions of the carrier on its surface facing the light-emitting diode chips are covered by the reflective coating.

4. The light-emitting diode according to claim 1, wherein the side faces of the at least two light-emitting diode chips are covered completely by the reflective coating.

5. The light-emitting diode according to claim 1, wherein the reflective coating is formed as one-piece.

6. The light-emitting diode according to claim 1, comprising a plurality of light-emitting diode chips spaced apart from each other on the mounting face, wherein spaces between the light-emitting diode chips are filled by the reflective coating.

7. The light-emitting diode according to claim 1, further comprising an electrically insulating intermediate carrier, wherein

the intermediate carrier is arranged between the light-emitting diode chips and the mounting face,

the light-emitting diode chips are affixed to the intermediate carrier, and

the reflective coating covers an exposed outer face of the intermediate carrier completely.

8. The light-emitting diode according to claim 1, wherein the light-emitting diode chips are directly affixed to the carrier at an upper side of the carrier and electrically connect in parallel with one another.

9. The light-emitting diode according to claim 1, wherein the light-emitting diode chips electrically connect to the metallic basic body and connect in parallel with one another via the metallic basic body.

10. The light-emitting diode according to claim 1, wherein

the carrier comprises a further electrically insulating layer affixed to the metallic basic body on the side facing the light-emitting diode chips,

the carrier comprises an electrically conductive layer affixed to the further electrically insulating layer on a side facing away from the metallic basic body,

the electrically conductive layer comprises a first conductor track electrically connected to the at least two light-emitting diode chips and a further conductor track electrically connected to the metallic basic body, and

the light-emitting diode chips electrically connect in parallel with one another via the metallic basic body.

11. The light-emitting diode according to claim 1, further comprising an electrically insulating layer affixed to the carrier on a lower side of the carrier facing away from the mounting face.

12. The light-emitting diode according to claim 11, wherein the electrically insulating layer

has a thermal conductivity of at least 2 W/(mK),

contains a ceramic material or boron nitride or consists of born nitride, and

has a thickness of 30 μ

m to 100 μ

m.

13. The light-emitting diode according to claim 1, comprising at least one opening in the carrier, said opening extending from an upper side of the carrier to a lower side of the carrier, said lower side facing away from the upper side, wherein

the at least one opening completely passes through the metallic basic body,

an inner face of the at least one opening is covered by an electrically insulating material, and

the at least one opening accommodates a fixing device that mounts the light-emitting diode.

14. The light-emitting diode according to claim 10, comprising at least one opening in the carrier, wherein

the at least one opening completely passes through the further electrically insulating layer and the electrically conductive layer, and

a side face of the further electrically insulating layer in the at least one opening and a side face of the electrically conductive layer in the at least one opening are covered by an electrically insulating material.

15. The light-emitting diode according to claim 1, wherein the metallic basic body accounts for at least 90% of the volume or at least 90% of the weight of the carrier.

16. A light-emitting diode comprising:

a carrier comprising a metallic basic body having an outer face comprising a mounting face; and

a plurality light-emitting diode chips affixed to the carrier at least indirectly at the mounting face,

wherein the light-emitting diode chips are embedded in a reflective coating, wherein side faces of the light-emitting diode chips are in direct contact with the reflective coating,

the light-emitting diode chips have radiation exit surfaces facing away from the carrier, wherein the light-emitting diode chips protrude with the radiation exit surfaces out of the reflective coating, or the reflective coating terminates flush with the radiation exit surfaces of the light-emitting diode chips,

the reflective coating completely covers the mounting face at its exposed regions, and

the light-emitting diode chips are spaced apart from each other on the mounting face, wherein spaces between the light-emitting diode chips are filled by the reflective coating.

17. The light-emitting diode according to claim 16, wherein the radiation exit surfaces of the light-emitting diode chips are free of the reflective coating and all the side faces of the light-emitting diode chips are covered by the reflective coating.

18. The light-emitting diode according to claim 16, wherein the reflective coating is diffusely reflective and formed by a matrix material and reflective particles introduced into the matrix material.

19. The light-emitting diode according to claim 18, further comprising a cover, wherein the cover

contains particles of a luminescence conversion material,

is mechanically fixed to the carrier, and

is arranged downstream of the light-emitting diode chips.

20. A light-emitting diode comprising a carrier with a mounting face and at least two light-emitting diode chips affixed to the carrier at least indirectly at the mounting face, wherein

the carrier comprises a metallic basic body,

an outer face of the metallic basic body comprises the mounting face,

the at least two light-emitting diode chips connect in parallel with one another,

the mounting face is arranged on an upper side of the carrier,

the light-emitting diode chips are directly affixed to the carrier at the mounting face,

the light-emitting diode chips electrically conductively connect to the metallic basic body,

the light-emitting diode chips connect in parallel with one another via the metallic basic body,

an electrically insulating layer is affixed to the carrier on a lower side of the carrier, and

the electrically insulating layer has a thermal conductivity of at least 2 W/(mK).