Light emitting diode apparatuses with heat pipes for thermal management

• US 7,095,110 B2
• Filed: 05/21/2004
• Issued: 08/22/2006
• Est. Priority Date: 05/21/2004
• Status: Expired due to Fees

• Current Assignee: Gelcore (General Electric Company)
• Original Assignee: Gelcore (General Electric Company)
• Inventors: Becker, Charles, Weaver, Stanton Earl Jr., Arik, Mehmet
• Primary Examiner(s): Dickey, Thomas L.
• Application Number:
  US10/851,273
• Publication Number:
  US 20050258438A1
• Time in Patent Office: 823 Days
• Field of Search: 257/712
• US Class Current: 257/712
• 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: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 33/648 the elements comprising fluids, e.g. heat-pipes

Abstract

A light emitting apparatus (10, 110, 210, 310, 410) includes one or more light emitting diode chips (12, 112, 212, 312, 412) disposed on a chip support wall (16, 116, 216) including printed circuitry (34, 134, 234, 360, 362, 460, 462) connecting with the light emitting diode chips. A heat pipe (24, 124, 224, 324, 424) has a sealed volume (22, 122, 222, 322, 422) defined by walls including the chip support wall and at least one additional wall (18, 20, 118, 120, 218). The heat pipe further includes a heat transfer fluid (26, 226, 326, 426) disposed in the sealed volume.

Claims

1. A light emitting apparatus comprising:

one or more light emitting diode chips; and

a passive heat pipe including (i) a generally planar chip support wall on which the one or more light emitting diode chips are disposed, (ii) at least one additional wall sealed with the chip support wall to define a closed interior volume, (iii) a heat transfer fluid disposed in the closed interior volume, and (iv) one or more wicking structures disposed at least on an interior surface of the chip support wall, the portion of the wicking structure disposed on the interior surface of the chip support wall including radiating wicks radiating outward toward edges of the chip support wall.

2. The light emitting apparatus as set forth in claim 1, wherein the passive heat pipe further comprises:

an annular condenser arranged around the radiating wicks.

3. The light emitting apparatus as set forth in claim 1, further comprising:

printed circuitry disposed on or in the chip support wall and electrically connecting with the light emitting diode chips.

4. The light emitting apparatus as set forth in claim 1, wherein the passive heat pipe defines a sub-mount on which the one or more light emitting diode chips are attached.

5. The A light emitting apparatus comprising:

one or more light emitting diode chips; and

a passive heat pipe including (i) a generally planar chip support wall on which the one or more light emitting diode chips are disposed, (ii) at least one additional wall sealed with the chip support wall to define a closed interior volume, (iii) a heat transfer fluid disposed in the closed interior volume, and (iv) one or more wicking structures disposed at least on an interior surface of the chip support wall, the chip support wall of the passive heat pipe including a metal core sealed with at least one additional wall to define the closed interior volume, one or more insulating layers disposed on the metal core, and printed circuitry disposed on or between the one or more insulating layers and electrically connecting with the at least one light emitting diode chip.

6. The light emitting apparatus as set forth in claim 5, wherein the one or more wicking structures include one or more wicking structures disposed on at least a portion of the at least one additional wall.

7. A light emitting apparatus comprising:

one or more light emitting diode chips;

a metal core printed circuit board on which the light emitting diode chips are disposed, the metal core printed circuit board including printed circuitry connecting with the light emitting diode chips; and

a heat pipe having walls including a metal core of the metal core printed circuit board sealed with at least one additional wall to define a sealed volume of the heat pipe, the heat pipe further including a heat transfer fluid disposed in the sealed volume.

8. The light emitting apparatus as set forth in claim 7, wherein the metal core of the metal core printed circuit board is soldered to the at least one additional wall to define the sealed volume of the heat pipe.

9. The light emitting apparatus as set forth in claim 7, wherein the metal core of the metal core printed circuit board is generally planar and the at least one additional wall includes a backside wall generally parallel with the generally planar metal core, the sealed volume being defined by a gap between the metal core and the backside wall.

10. The light emitting apparatus as set forth in claim 7, wherein the heat pipe further comprises:

a wicking structure disposed inside the sealed volume on an inside surface of the at least one additional wall.

11. The light emitting apparatus as set forth in claim 7, wherein the heat pipe further comprises:

a wicking structure disposed inside the sealed volume on an inside surface of the metal core of the metal core printed circuit board.

12. The light emitting apparatus as set forth in claim 7, wherein the printed circuitry includes bonding pads electrically connected with electrodes of the one or more light emitting diode chips by one of flip chip bonding and wire bonding.

13. A light emitting apparatus comprising:

at least one light emitting diode chip; and

a passive heat pipe having a sealed volume defined by (i) a chip support wall on which the at least one light emitting diode chip is disposed, (ii) a backside wall, and (iii) one or more sidewalls extending between the chip support wall and the backside wall, a separation between the chip support wall and the backside wall being smaller than a lateral dimension of the chip support wall, the heat pipe further including a heat transfer fluid disposed in the sealed volume.

14. The light emitting apparatus as set forth in claim 13, wherein the heat pipe further comprises:

a wicking structure disposed inside the sealed volume on at least one of the chip support wall and the backside wall.

15. The light emitting apparatus as set forth in claim 13, wherein the heat pipe defines a sub-mount, the at least one light emitting diode chip being attached to the sub-mount.

16. The light emitting apparatus as set forth in claim 15, wherein the sub-mount includes one or more conductive traces disposed on the chip support wall and electrically connecting with electrodes of the at least one light emitting diode chip.

17. The light emitting apparatus as set forth in claim 16, wherein the electrodes are one of (i) flip chip bonded, and (ii) wire bonded, to the one or more conductive traces.

18. The light emitting apparatus as set forth in claim 13, wherein the chip support wall of the heat pipe includes a printed circuit board having printed circuitry electrically connecting with the at least one light emitting diode chip.