Compressible thermal interface materials

Patent metadata

Field	Value
Publication number	US-10068830-B2
Application number	US-201515117862-A
Country	US
Kind code	B2
Filing date	Feb 4, 2015
Priority date	Feb 13, 2014
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

Provided is a compressible thermal interface material including a polymer, a thermally conductive filler, and a phase change material. A formulation for forming a compressible thermal interface material and an electronic component including a compressible thermal interface material are also provided.

First claim

The invention claimed is:

1. A compressible thermal interface material comprising:
at least one polymer;
at least one thermally conductive filler; and
at least one phase change material, wherein the at least one phase change material includes a wax having a needle penetration value of at least 50 as determined at 25° C. according to ASTM D1321.

2. The compressible thermal interface material of claim 1 , wherein the compressible thermal interface material has a compressibility of at least 5% under an applied contact pressure of 40 psi.

3. The compressible thermal interface material of claim 1 , wherein the compressible thermal interface material has a springback ratio of 50% or less.

4. The compressible thermal interface material of claim 1 , wherein the at least one phase change material comprises a second wax, the second wax having a needle penetration value of less than 50 as determined at 25° C. according to ASTM D1321.

5. The compressible thermal interface material of claim 1 , wherein the at least one phase change material comprises a wax selected from the group consisting of: a polyethylene wax, a copolymer of ethylene-vinyl acetate wax, and an oxidized polyethylene wax.

6. The compressible thermal interface material of claim 1 , wherein the at least one thermally conductive filler includes a filler selected from the group consisting of metals, alloys, nonmetals, metal oxides, ceramics, and combinations thereof.

7. The compressible thermal interface material of claim 1 , wherein the at least one thermally conductive filler comprises 10 wt. % to 95 wt. % of the total weight of the compressible thermal interface material.

8. The compressible thermal interface material of claim 1 , wherein the at least one polymer includes a polymer is selected from the group consisting of: ethylene-propylene rubbers (EPR), ethylene-propylene diene monomer rubbers (EPDM), polyethylene-butylene, and polyethylene-butylene-styrene, polybutadiene, hydrogenated polybutadiene mono-ol, hydrogenated polypropadiene mono-ol, hydrogenated polypentadiene mono-ol, polybutadiene diol, hydrogenated polypropadiene diol, and hydrogenated polypentadiene diol.

9. The compressible thermal interface material of claim 1 , wherein the at least one polymer is hydrogenated polybutadiene.

10. The compressible thermal interface material of claim 1 , further comprising at least one coupling agent, at least one antioxidant, and at least one crosslinking agent.

11. The compressible thermal interface material of claim 1 , further comprising at least one silicone gel.

12. The compressible thermal interface material of claim 1 , further comprising:
a middle layer comprising the at least one polymer, the at least one thermally conductive filler, and the wax having a needle penetration value of at least 50 as determined at 25° C. according to ASTM D1321;
a first surface layer including at least one phase change material and at least one thermally conductive filler, the first surface layer contacting a first surface of the middle layer; and
a second surface layer including at least one phase change material and at least one thermally conductive filler, the second surface layer contacting a second surface of the middle layer.

13. The compressible thermal interface material of claim 12 , wherein a weight percentage content of the at least one thermally conductive filler in the middle layer is less than or equal to the weight percentage content of at least one thermally conductive filler in at least one of the first and second surface layers.

14. The compressible thermal interface material of claim 12 , wherein the weight percentage of the at least one thermally conductive filler in each of the first and second surface layers is independently from about 70 wt. % to about 99 wt. %.

15. A formulation for forming a compressible thermal interface material comprising:
at least one solvent;
at least one polymer;
at least one thermally conductive filler; and
at least one phase change material, wherein the at least one phase change material includes a wax having a needle penetration value of at least 50 as determined at 25° C. according to ASTM D1321.

16. The formulation of claim 15 , wherein the formulation has a viscosity of 1,000 centipoise to 100,000,000 centipoise.

17. An electronic component comprising:
a heat sink;
an electronic chip;
a compressible thermal interface material positioned between the heat sink and electronic chip, the compressible thermal interface material including: at least one polymer, at least one thermally conductive filler, and at least one wax having a needle penetration value of at least 50 as determined at 25° C. according to ASTM D1321.

18. The electronic component of claim 17 , wherein a first surface of the compressible thermal interface material is in contact with a surface of the electronic chip and a second surface of the compressible thermal interface material is in contact with the heat sink.

19. The electronic component of claim 17 , further comprising a heat spreader positioned between the heat sink and the electronic chip, wherein a first surface of the compressible thermal interface material is in contact with a surface of the electronic chip and a second surface of the compressible thermal interface material is in contact with the heat spreader.

20. The electronic component of claim 17 , further comprising a heat spreader positioned between the heat sink and the electronic chip, wherein a first surface of the compressible thermal interface material is in contact with a surface of the heat spreader and a second surface of the compressible thermal interface material is in contact with the heat sink.

Assignees

• Honeywell Int Inc
• Zeng Liang
• Liu Ya Qun
• Chang Jerry
• Zhang Bright
• Ding Zhe
• Wang Wei Jun
• Huang Hong Min

Inventors

• Zeng Liang
• Liu Ya Qun
• Chang Wei
• Zhang Liqiang
• Ding Zhe
• Wang Wei Jun
• Huang Hong Min

Classifications

• H10W40/70

  Fillings or auxiliary members in containers or in encapsulations for thermal protection or control · CPC title

• H10W40/22

  characterised by their shape, e.g. having conical or cylindrical projections · CPC title

• H10W40/251 Primary

  Organics · CPC title

• C09K5/063 Primary

  Materials absorbing or liberating heat during crystallisation; Heat storage materials · CPC title

• H01L23/42

  Electricity · mapped topic