Flexible Heat Spreader with Differential Thermal Conductivity

• US 20160170454A1
• Filed: 12/15/2014
• Published: 06/16/2016
• Est. Priority Date: 12/15/2014
• Status: Active Grant

• Current Assignee: Dell Products LP (Dell Technologies Inc.)
• Original Assignee: Dell Products LP (Dell Technologies Inc.)
• Inventors: Aurongzeb, Deeder M., Coolidge, Daniel, Thompson, Richard C.
• Granted Patent: US 10,088,878 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 1/20 Cooling means

Abstract

A heat spreader which is configured using a composite of materials to provide localized heat spreading in certain directions across portions of the heat spreader while providing generalized heat spreading in multiple directions across other portions of the heat spreader. In certain embodiments, the localized heat spreading is across an XY plane and the generalized heat spreading is substantially continuous in XYZ directions.

Claims

1. A heat spreader comprising:

a first portion, the first portion comprising graphene, the first portion providing localized heat spreading in certain directions across the heat spreader; and

,

a second portion, the second portion comprising a solid-solid phase change material, the second portion providing generalized heat spreading in multiple directions across the heat spreader.

2. The heat spreader of claim 1, wherein:

the localized heat spreading is across an XY plane of the heat spreader and the generalized heat spreading is substantially continuous in XYZ directions across the heat spreader.

3. The heat spreader of claim 1, wherein:

the graphene is composed of a 70% purity, has a conductivity in low 100 W/MK at 5 um and saturates at >

50 um with up to 800 w/mk.

4. The heat spreader of claim 1, wherein:

the first portion of the heat spreader comprises graphene which comprise a plurality of indentations on one side where the indentations are filled with insulating resin.

5. The heat spreader of claim 1, wherein:

a thermally conductive metal is incorporated into the first portion of the heat spreader.

6. The heat spreader of claim 5, wherein:

the thermally conductive metal comprises metal posts which are incorporated by depositing a spreader on a thermoformed graphene composite slab.

7. A system comprising:

a processor;

a data bus coupled to the processor; and

a heat spreader thermally coupled to the processor, the heat spreader comprising

a first portion, the first portion comprising graphene, the first portion providing localized heat spreading in certain directions across the heat spreader; and

,

a second portion, the second portion comprising a solid-solid phase change material, the second portion providing generalized heat spreading in multiple directions across the heat spreader.

8. The system of claim 7, wherein:

the localized heat spreading is across an XY plane of the heat spreader and the generalized heat spreading is substantially continuous in XYZ directions across the heat spreader.

9. The system of claim 7, wherein:

the graphene is composed of a 70% purity, has a conductivity in low 100 W/MK at 5 um and saturates at >

50 um with up to 800 w/mk.

10. The system of claim 7, wherein:

the first portion of the heat spreader comprises graphene which comprise a plurality of indentations on one side where the indentations are filled with insulating resin.

11. The system of claim 7, wherein:

a thermally conductive metal is incorporated into the first portion of the heat spreader.

12. The system of claim 11, wherein:

the thermally conductive metal comprises metal posts which are incorporated by depositing a spreader on a thermoformed graphene composite slab.