EMBEDDED LIQUID PUMP AND MICROCHANNEL COOLING SYSTEM

• US 20040130874A1
• Filed: 01/06/2003
• Published: 07/08/2004
• Est. Priority Date: 01/06/2003
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Chrysler, Gregory M., Maveety, James G., Garner, Michael C.
• Granted Patent: US 6,785,134 B2
• Time in Patent Office: Days
• US Class Current: 361/699
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 23/42 Fillings or auxiliary members in containers or encapsulations selected or arranged to facilitate heating or cooling
• CPC Class Codes: H01L 23/473 by flowing liquids H01L23/4332, H01L23/4338 take precedence
• 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 2924/15311 being a ball array, e.g. BGA

Abstract

Apparatus and methods in accordance with the present invention provide self-contained, closed-loop microchannel/electrokinetic pump cooling systems that can be integrated into the microelectronic die and the integrated heat sink to provide microelectronic die cooling. Microchannel/electrokinetic pump cooling systems utilize active cooling technology to reduce thermal gradients and operating temperature of a microelectronic die. This system disclosed here will enhance heat dissipation and provide immediate cooling of localized hot spots within the microelectronic die. This will have the effect of reducing the microelectronic die temperature or spreading the heat internally within the microelectronic die depending on the layout of the microchannels.

Claims

1. A heat dissipation device comprising:

an electrokinetic pump; and

a substrate comprising microchannels in fluid communication with the electrokinetic pump.

2. The heat dissipation device of claim 1, wherein the substrate comprises an integrated heat spreader, the electrokinetic pump housed within the integrated heat spreader.

3. The heat dissipation device of claim 1, wherein the substrate comprises an integrated heat spreader, the electrokinetic pump housed within the integrated heat spreader, the electrokinetic pump comprising a reservoir, electrodes, and fluid, the reservoir formed integral with the integrated heat spreader, the reservoir in fluid communication with the microchannels, the electrodes adapted to provide a pressure differential by electrolysis of the fluid.

4. The heat dissipation device of claim 1, further comprising a microelectronic die, wherein the substrate comprises an integrated heat spreader, the electrokinetic pump housed within the integrated heat spreader, the microchannels comprising grooves on a microelectronic die-facing side, the integrated heat spreader coupled to a backside of the microelectronic die, the backside forming a fourth wall of the microchannels.

5. The heat dissipation device of claim 3, further comprising a microelectronic die comprising internal die microchannels, the die microchannels in fluid communication with the microchannels within the integrated heat spreader.

12. The method of claim 11, wherein providing a substrate comprising microchannels in fluid communication with the electrokinetic pump comprises:

providing an integrated heat spreader, the electrokinetic pump housed within the integrated heat spreader.

6. A microelectronic assembly, comprising:

a microelectronic die; and

a heat dissipation device, comprising;

an electrokinetic pump; and

a substrate comprising microchannels in fluid communication with the electrokinetic pump, the substrate in thermal communication with the microelectronic die.

7. The microelectronic assembly of claim 6, wherein the substrate comprises an integrated heat spreader, the electrokinetic pump housed within the integrated heat spreader.

8. The microelectronic assembly of claim 6, wherein the substrate comprises an integrated heat spreader, the electrokinetic pump housed within the integrated heat spreader, the electrokinetic pump comprising a reservoir, electrodes, and fluid, the reservoir formed integral with the integrated heat spreader, the reservoir in fluid communication with the microchannels, the electrodes adapted to provide a pressure differential by electrolysis of the fluid.

9. The heat dissipation device of claim 8, wherein the microchannels comprise grooves on a microelectronic die-facing side of the integrated heat spreader, the integrated heat spreader coupled to a backside of the microelectronic die, the backside forming a fourth wall of the microchannels.

10. The heat dissipation device of claim 8, wherein the microelectronic die comprises internal die microchannels, the die microchannels in fluid communication with the microchannels within the integrated heat spreader.

11. A method for actively cooling a microelectronic die, comprising:

providing an electrokinetic pump;

providing a substrate comprising microchannels in fluid communication with the electrokinetic pump; and

thermally coupling the substrate with the microelectronic die, the microchannels positioned to move heat from areas of high heat flux to areas of low heat flux to reduce thermal gradients within the microelectronic die.

13. The method of claim 11, wherein providing an integrated heat spreader, comprises:

providing an integrated heat spreader, the electrokinetic pump comprising a reservoir, electrodes, and fluid, the reservoir formed integral with the integrated heat spreader, the reservoir in fluid communication with the microchannels,

providing the electrodes with a voltage sufficient to electrolyze the fluid driving the fluid through the microchannels by a pressure differential caused by electrolysis of the fluid.

14. The method of claim 13, further comprising:

forming grooves in a die-facing surface of the integrated heat spreader;

coupling the integrated heat spreader to a backside of the microelectronic die, the backside forming a fourth wall of the microchannels.

15. The method of claim 13, further comprising:

forming internal die microchannels within the microelectronic die, the die microchannels in fluid communication with the microchannels within the integrated heat spreader.