LOW-PROFILE HEAT-SPREADING LIQUID CHAMBER USING BOILING

• US 20080236795A1
• Filed: 03/26/2007
• Published: 10/02/2008
• Est. Priority Date: 03/26/2007
• Status: Abandoned Application

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Kim, Jesse Jaejin, Kim, Joo Han, Kwark, Sang M., You, Seung Mun
• Application Number:
  US11/690,937
• Publication Number:
  US 20080236795A1
• Time in Patent Office: Days
• US Class Current: 165/104.21
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• 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

Abstract

Systems and fabrication methods are disclosed for a heat spreader to cool a device. The heat spreader has first and second opposing proximal surfaces defining a chamber having a liquid therein; and one or more structures mounted in the chamber to induce a liquid flow pattern during a boiling of the liquid to distribute heat.

Claims

1. A heat spreader to cool a device, comprising:

first and second opposing proximal surfaces defining a chamber containing a liquid therein; and

one or more structures mounted in the chamber to induce a liquid flow pattern during boiling of the liquid to cool the device.

2. The heat spreader of claim 1, wherein each surface comprises a plate.

3. The heat spreader of claim 2, wherein the plate is rigid.

4. The heat spreader of claim 1, wherein one surface comprises one side of a plate and the other surface contacts the device.

5. The heat spreader of claim 1, wherein the device comprises a flip-chip die, comprising a plate positioned opposite to the flip-chip die, wherein the flip-chip die and the plate define the chamber.

6. The heat spreader of claim 5, wherein the device composes a flip-chip die with a circumferential plate, comprising a plate positioned opposite to the flip chip die with circumferential plate, wherein the flip-chip die with circumferential plate and the opposing plate define the chamber.

7. The heat spreader of claim 5, wherein the device composes a flip-chip die with an adjoining plate, comprising a plate positioned opposite to the flip-chip die with adjoining plate, wherein the flip-chip die with adjoining plate and the opposing plate define the chamber.

8. The heat spreader of claim 1, wherein the one or more structures are mounted on at least one of the opposing surfaces.

9. The heat spreader of claim 1, wherein the one or more structures are mounted between the opposing surfaces.

10. The heat spreader of claim 1, wherein the first surface thermally contacts the device and wherein the one or more structures are mounted on the first surface.

11. The heat spreader of claim 1, wherein the first surface thermally contacts the device and wherein the one or more structures are mounted on the second surface.

12. The heat spreader of claim 1, wherein the first and second opposing surfaces are separated by a small gap.

13. The heat spreader of claim 1, wherein the first and second opposing surface have a first separation distance above a predetermined region on device and a second separation distance surrounding the predetermined region and wherein the second separation distance is larger than the first separation distance.

14. The heat spreader of claim 1, wherein the first and second opposing surface have a uniform separation distance.

15. The heat spreader of claim 1, wherein the liquid flow pattern is induced by bubble pumping.

16. The heat spreader of claim 15, wherein the bubble pumping is formed through Taylor instability of condensate when horizontally placed with the surface at a predetermined position so a heated surface faces vapor space inside the chamber.

17. The heat spreader of claim 1, wherein the liquid flow pattern improves nucleate boiling heat transfer and also removes locally generated vapor dryout zone at a heated area.

18. The heat spreader of claim 1, wherein one surface transfers heat to boil the liquid.

19. The heat spreader of claim 1, wherein the liquid comprises one of:

water, acetone, ethanol, methanol, refrigerant, and mixtures thereof.

20. The heat spreader of claim 1, wherein the liquid contains nanoparticles.

21. The heat spreader of claim 1, wherein the liquid is selected to boil at a predetermined temperature to match a predetermined thermal requirement of the device.

22. The heat spreader of claim 1, wherein the structure comprises one of:

a fin structure, a rib structure.

23. The heat spreader of claim 1, wherein each structure comprises an elongated bar and the one or more structures are placed adjacent a locally heated area.

24. The heat spreader of claim 1, wherein each structure comprises an elongated bar and the one or more structures are spaced apart to surround a locally heated area.

25. The heat spreader of claim 24, wherein the locally heated area is centrally positioned to the one or more structures.

26. The heat spreader of claim 24, wherein the locally heated area is positioned closer to one structure than another structure.

27. The heat spreader of claim 1, comprising a coating formed on the surface.

28. The heat spreader of claim 1, wherein the surface comprises one of:

a sintered surface, a machined surface, a micro-porous coating, a thermally-conductive micro-porous coating (TCMC).

29. The heat spreader of claim 36, comprising a gap between 0.1 and three millimeters between the coating and the surface facing the coating.

30. The heat spreader of claim 1, wherein the surface comprises a coating formed in one of:

a recessed area, a flat area, an extruded area.

31. The heat spreader of claim 1, wherein the surface is formed using stamping.

32. The heat spreader of claim 1, wherein the one or more structures are formed using one of:

placing wires, placing ribs, shaping ribs, stamping ribs, machining ribs.

33. The heat spreader of claim 1, comprising a gap of less than 3.5 millimeters between the first and second surfaces.

34. The heat spreader of claim 1, comprising a gap between 0.1 millimeter and 3.5 millimeters between the first and second surfaces.

35. The heat spreader of claim 1, comprising a gap selected from a group consisting of about 0.1 mm, 1 mm, 1.5 mm, 2 mm, 3 mm, and 3.5 mm between the first and second surfaces.

36. The heat spreader of claim 1, comprising a heat sink or cold plate coupled to one of the surfaces.

37. The heat spreader of claim 1, comprising one or more fins coupled to one of the surfaces.

38. The heat spreader of claim 1, wherein the one or more structures provide mechanical support for the chamber.

39. The heat spreader of claim 1, wherein the surfaces comprise 3D shapes or volumes.