LIGHT-EMITTING DIODE ASSEMBLY AND METHOD OF FABRICATION

• US 20080175008A1
• Filed: 01/23/2007
• Published: 07/24/2008
• Est. Priority Date: 01/23/2007
• Status: Active Grant

• Current Assignee: Foxconn Technology Co., Ltd.
• Original Assignee: Foxconn Technology Co., Ltd.
• Inventors: LIN, YEU-LIH, HU, TSENG-HSIANG, TAN, LI-KUANG
• Granted Patent: US 7,753,568 B2
• Time in Patent Office: Days
• US Class Current: 362/373
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• CPC Class Codes: F21V 29/59 with forced flow of the coolant
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/80 with pins or wires
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements
• CPC Class Codes: H01L 33/648 the elements comprising fluids, e.g. heat-pipes
• CPC Class Codes: H05K 1/0272 Adaptations for fluid transport, e.g. channels, holes
• CPC Class Codes: H05K 1/053 the metal substrate being covered by an inorganic insulating layer
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A light-emitting diode (LED) assembly includes a heat dissipation device (30) and at least one LED (10). The heat dissipation device has a connecting surface (33) with circuitry (20) being directly formed thereon. The at least one LED is electrically connected with the circuitry, and is maintained in thermal and mechanical contact with the connecting surface to dissipate heat generated thereby through the heat dissipation device. A method for making the LED assembly includes steps of: (A) providing a heat dissipation device having a surface for the LED to be mounted thereon; (B) insulating the surface; (C) forming circuitry on the insulated surface directly to obtain a connecting surface; (D) attaching the LED to the connecting surface of the heat dissipation device thermally and mechanically, and connecting the LED with the circuitry electrically to form the LED assembly.

Claims

1. A light-emitting diode (LED) assembly, comprising:

a heat dissipation device comprising a connecting surface, the connecting surface having circuitry being directly formed thereon; and

at least one LED being electrically connected with the circuitry formed on the connecting surface, and being maintained in thermal and mechanical contact with the connecting surface of the heat dissipation device to dissipate heat generated thereby through the heat dissipation device.

2. The assembly of claim 1, wherein the heat dissipation device comprises a hollow body in which a working fluid is provided, an outer surface of the hollow body forming the connecting surface for the at least one LED to be mounted thereon.

3. The assembly of claim 2, wherein the heat dissipation device is a heat pipe with a planar-shaped outer surface forming the connecting surface.

4. The assembly of claim 3, wherein the heat pipe comprises an evaporating section and a condensing section, the connecting surface being formed on an outer surface of the evaporating section, a plurality of fins being thermally attached to the condensing section of the heat pipe.

5. The assembly of claim 3, further comprising a heat sink having a chassis and a plurality of fins extending from the chassis, the chassis defining a groove therein, the groove having a shape conforming to that of the heat pipe and receiving the heat pipe therein.

6. The assembly of claim 2, wherein the heat dissipation device is a vapor chamber.

7. The assembly of claim 2, wherein the heat dissipation device is a cold plate in which a flow channel is defined for passage of working fluid.

8. The assembly of claim 2, further comprising a plurality of fins being thermally attached to the hollow body.

9. The assembly of claim 1, wherein the heat dissipation device comprises a chassis and a plurality of fins extending from the chassis, the chassis forming the connecting surface on an outer surface thereof for the at least one LED to be mounted thereon.

10. The assembly of claim 1, wherein the heat dissipation device comprises a heat spreader forming the connecting surface, a heat pipe having an evaporating section being thermally attached to the heat spreader and a condensing section, and a plurality of fins being thermally attached to the condensing section of the heat pipe.

11. A method of making an LED assembly, comprising:

providing a heat dissipation device having a surface for the LED to be mounted thereon;

insulating the surface of the heat dissipation device by applying an insulating layer to the surface;

forming circuitry on the insulating layer to obtain a connecting surface consisting of the surface of the heat dissipation device with the insulating layer and the circuitry; and

attaching the LED to the connecting surface of the heat dissipation device thermally and mechanically, and connecting the LED with the circuitry electrically.

12. The method of claim 11, wherein the surface of the heat dissipation device is insulated through one of the following methods:

vacuum sputtering, vaporization and anodizing.

13. The method of claim 11, wherein the circuitry is formed on the insulating layer by firstly covering the insulating layer with a copper foil layer thereon through one of the following methods:

sputtering, hot-press, electroless copper deposition and electrodeposition, and then photoresist coating, exposing and etching the copper foil layer.

14. The method of claim 11, further comprising a step of surface activation before forming the circuitry, the surface activation being one of the following methods:

silver spraying, sandblast, and coursing.

15. The method of claim 11, wherein the heat dissipation device is one of the following devices:

fin-type heat sink, heat pipe, vapor chamber, cold plate, and the heat pipe, the vapor chamber or the cold plate is with fins thermally attached thereto.

16. An LED assembly comprising:

a heat dissipation device having a surface coated with an insulating layer thereon, and circuitry formed on the insulating layer to thereby form a connecting surface on the heat dissipation device; and

at least an LED mounted on the connecting surface, wherein heat generated by the at least an LED is transferred to the heat dissipation device to be dissipated and the at least an LED is electrically connected with the circuitry.

17. The LED assembly of claim 16, wherein the heat dissipation device has a chassis, the connecting surface being formed at a bottom of the chassis, a plurality of fins projecting upwardly from a top of the chassis.

18. The LED assembly of claim 16, wherein the heat dissipation device has a heat sink and a heat pipe embedded in a bottom of the heat sink, the connecting surface being formed at a bottom of the heat pipe.

20. The LED assembly of claim 16, wherein the heat dissipation device is a vapor chamber with a bottom forming the connecting surface, a plurality of fins being positioned to a top of the vapor chamber.

19. The LED assembly of clam 16, wherein the heat dissipation device has a heat pipe with an evaporating portion and a condensing portion, a plurality of fins being thermally connected to the condensing portion of the heat pipe, the connecting surface being formed on a part of the evaporating portion of the heat pipe.