Heat-dissipating copper foil and graphene composite

Patent metadata

Field	Value
Publication number	US-9709348-B2
Application number	US-201615288346-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 27, 2015
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A method of producing a composite heat dissipating structure by depositing a slurry of graphene particles upon a copper foil, drying the slurry to form a layer of graphene in contact with the copper foil, and consolidating the layer of graphene under pressure to reduce the thickness of the graphene layer and recovering the composite heat dissipating structure. Heat dissipating copper foils and composite heat dissipating structures and electronic devices incorporating the same are also disclosed herein.

First claim

I claim:

1. A heat dissipating copper foil comprising:
(a) a copper content greater than 90%;
(b) an area weight is in the range of 280 to 900 (g/m 2 );
(c) the copper foil comprising two surfaces, said surface comprising a drum-side and a deposited-side;
(d) the deposited-side of the copper foil possesses a surface roughness (Rz) that does not exceed 1.0 μm; and
(e) the copper foil exhibits a surface tension in the range of 44 to 68 dyne/cm.

2. The heat dissipating copper foil of claim 1 , wherein the surface roughness (Rz) of the drum-side does not exceed 2.5 μm.

3. The heat dissipating copper foil of claim 1 , wherein the drum-side of the copper foil exhibits an MD gloss lower than 180 at a light incident angle of 60°.

4. The heat dissipating copper foil of claim 1 , wherein the surface roughness (Rz) of the drum-side is in the range of 1.1 to 2.5 μm.

5. The heat dissipating copper foil of claim 1 , wherein the surface roughness (Rz) of the deposited-side is in the range of 0.3 to 1.0 μm.

6. The heat dissipating copper foil of claim 1 , wherein a lightness value L* of the deposited-side based on the L*a*b* color system, is in the range of 20 to 40.

7. The heat dissipating copper foil of claim 6 , wherein the a* value of the deposited-side is in the range of 6 to 11 and b* value of the deposited-side is in the range of 3 to 8, based on the L*a*b* color system.

8. The heat dissipating copper foil of claim 1 , wherein the copper foil having a grain size larger than 30 nm.

9. A composite heat dissipating structure comprising the copper foil according to claim 1 further comprising a layer of adhesive, and a pressure consolidated graphene layer, the layer of adhesive being on a surface of the graphene layer opposite the contact of the graphene layer with the copper foil or on a surface of the copper foil opposite the contact of the graphene layer with the copper foil.

10. The composite heat dissipating structure of claim 9 , wherein the pressure consolidated graphene layer has a thickness in the range of 3 to 50 μm.

11. The composite heat dissipating structure of claim 9 , wherein the graphene layer comprises a surface opposite the copper foil, said graphene layer surface having a lightness value L* in the range of 20 to 60, based on the L*a*b* color system.

12. The composite heat dissipating structure comprising the copper foil according to claim 1 , further comprising a pressure consolidated graphene layer in contact with both the drum- and deposited-sides of the copper foil.

13. The composite heat dissipating structure of claim 9 , wherein the pressure consolidated graphene layer comprises a water-based adhesive binder, graphene powder, and a conductive material selected from the group consisting of carbon black, graphite and combinations thereof.

14. A composite heat dissipating structure, said structure comprising:
an electrodeposited copper foil, said copper foil having an area weight in the range of 280 to 900 g/m 2 ;
the electrodeposited copper foil comprising two surfaces, said surface comprising a drum-side and a deposited-side;
the deposited-side of the copper foil having a surface roughness (Rz) in the range of 0.3 to 1.0 μm;
the copper foil exhibits a surface tension in the range of 44 to 68 dyne/cm; and,
a graphene layer in combination said copper foil, the graphene layer being in contact with at least the one side of drum-side and deposited-side of the copper foil;
wherein the graphene layer comprises a surface opposite the copper foil, said graphene layer surface having a lightness value L* in the range of 20 to 60, based on the L*a*b* color system.

15. The composite heat dissipating structure of claim 14 , further comprising a graphene layer in contact with both the drum- and deposited-sides of the copper foil.

16. The composite heat dissipating structure of claim 14 , wherein the drum-side of the copper foil exhibits the surface roughness (Rz) in the range of 1.1 to 2.5 μm.

17. The composite heat dissipating structure of claim 14 , wherein the drum-side of the copper foil exhibits an MD gloss lower than 180 at a light incident angle of 60°.

18. The composite heat dissipating structure of claim 14 , further comprising a layer of adhesive, the layer of adhesive being on a surface of the graphene layer opposite the contact of the graphene layer with the copper foil or on a surface of the copper foil opposite the contact of the graphene layer with the copper foil.

19. An electronic device comprising the composite heat dissipating structure of claim 1 .

20. A method of forming a composite heat dissipating structure, the method comprising:
providing an electrodeposited copper foil according to claim 1 having a drum-side and a deposited-side;
coating a slurry of graphene powder on the deposited-side of the copper foil;
drying the slurry to form a layer of graphene in contact with the deposited-side of the copper foil; the layer of graphene having a first thickness;
reducing the thickness of the layer of graphene layer by consolidating the graphene layer in combination with the copper foil under pressure to form a reduced thickness of graphene in contact with the copper foil; and,
recovering the composite heat dissipating structure.

21. The method of claim 20 , further comprising applying a layer of adhesive to the graphene layer after the reducing step.

22. The method of claim 20 , further comprising coating a slurry of graphene powder on the drum-side of the copper foil.

23. The method of claim 20 , wherein the slurry is an aqueous slurry.

24. The method of claim 20 , where the step of reducing the thickness of the graphene layer comprises consolidating the graphene layer with the copper foil at a pressure of at least 1000 kg in a roller press.

Assignees

• Chang Chun Petrochemical Co Ltd

Inventors

• Cheng Kuei-Sen

Classifications

• H10W40/255

  having a laminate or multilayered structure, e.g. direct bond copper [DBC] ceramic substrates · CPC title

• H10W40/253

  Semiconductors · CPC title

• H10W40/258

  Metallic materials (H10W40/254, H10W40/257, H10W40/255, H10W40/251, H10W40/253 take precedence) · CPC title

• H10W40/037

  Assembling together parts thereof · CPC title

• H10W40/226 Primary

  characterised by projecting parts, e.g. fins to increase surface area (leadframes for cooling H10W70/461) · CPC title