Methods of forming serpentine thermal interface material and structures formed thereby

Patent metadata

Field	Value
Publication number	US-9230877-B2
Application number	US-201213724511-A
Country	US
Kind code	B2
Filing date	Dec 21, 2012
Priority date	Dec 21, 2012
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

Methods of forming a microelectronic packaging structure and associated structures formed thereby are described. Those methods may include forming a thermal interface material comprising a thermally conductive serpentine foil located between a first and a second interface material. The serpentine foil may be in a parallel position or a rotated position, in embodiments.

First claim

What is claimed is:

1. A method of forming a thermal interface material (TIM) comprising:
forming a first interface material on a substrate;
placing a serpentine foil on the first interface material, wherein the serpentine foil comprises a repeating serpentine pattern; and
forming a second interface material on the serpentine foil, wherein an apex portion of the serpentine foil is in contact with and extends into at least one of the first and second interface materials.

2. The method of claim 1 further comprising wherein the apex portion of the serpentine foil is disposed in a substantially parallel position with at least one of the first and second interface materials.

3. The method of claim 1 further comprising wherein the apex portion of the serpentine foil is disposed in a rotated alignment with respect to at least one of the first and second interface materials.

4. The method of claim 1 further comprising wherein the serpentine foil comprises a thickness of between about 100 microns to about 1000 microns.

5. The method of claim 1 further comprising wherein at least one of the first and second interface materials comprise a thickness of between about 1 to about 100 microns.

6. The method of claim 1 further comprising wherein the TIM comprises an air space adjacent an interior portion of the serpentine foil.

7. The method of claim 1 further comprising wherein the repeating serpentine pattern comprises a repeating loop structure.

8. The method of claim 1 further comprising wherein the serpentine foil comprises copper.

9. The method of claim 1 further comprising wherein at least one of the first and second interface materials comprises at least one of thermal grease, thermal epoxy, polymer materials, phase-change materials, tin and indium.

10. The method of claim 1 further comprising wherein the rotated alignment comprises wherein the apex is disposed at an angle with respect to at least one of the first and second interface materials, and wherein the angle is not substantially parallel to the first and second interface materials.

11. The method of claim 10 further comprising wherein the angle comprises between about a 10 to about an 80 degree angle with respect to the first and second interface materials.

12. The method of claim 1 further comprising wherein the TIM comprises a portion of a package structure.

13. The method of claim 12 further comprising wherein the TIM is formed between a bottom portion of a device and a top portion of the package structure.

14. The method of claim 13 wherein the device comprises one of a microelectronic memory die and a central processing unit die.

15. The method of claim 12 wherein the TIM is formed between a top portion of a device disposed on the package structure and an integrated heat structure.

16. The method of claim 15 wherein the device comprises one of a microelectronic memory die and a central processing unit die.

17. The method of claim 1 further comprising wherein the serpentine foil is formed by a crimping process.

18. The method of claim 17 further comprising wherein the serpentine foil is compressed.

19. The method of claim 18 wherein the serpentine foil is rotated with a shear force process.

20. The method of claim 17 , wherein the crimping process comprises feeding a foil material through a pair of intermeshing gears.

21. The method of claim 20 , further including singulating the foil material into individual, singulated serpentine foil pieces.

22. The method of claim 21 , further including compressing the singulated serpentine foil piece to form the serpentine foil.

23. The method of claim 22 , wherein compressing the serpentine foil comprises placing the singulated serpentine foil piece between two flat plates with a controlled spacing therebetween and compressing the singulated serpentine foil with additional plates between the two flat plates and on opposing ends of the singulated serpentine foil.

24. A thermal interface material (TIM) structure comprising:
a first interface material on a substrate;
a serpentine foil disposed on the first interface material, wherein the serpentine foil comprises a repeating serpentine pattern; and
a second interface material on the serpentine foil, wherein an apex portion of the serpentine foil is in contact with and extends into at least one of the first and second interface materials.

25. The structure of claim 24 further comprising wherein the apex portion of the serpentine foil is disposed in a substantially parallel position with at least one of the first and second interface materials.

26. The structure of claim 24 further comprising wherein the apex portion of the serpentine foil is disposed in a rotated alignment with respect to at least one of the first and second interface materials.

27. The structure of claim 24 further comprising wherein the serpentine foil comprises a thickness of between about 100 microns to about 1000 microns.

28. The structure of claim 24 further comprising wherein at least one of the first and second the interface materials comprises a thickness of between about 1 and about 100 microns.

29. The structure of claim 24 further comprising wherein the TIM comprises an air space adjacent an interior portion of the serpentine foil.

30. The structure of claim 24 further comprising wherein the repeating serpentine pattern comprises a repeating loop structure.

31. The structure of claim 24 further comprising wherein the serpentine foil comprises copper.

32. The structure of claim 24 further comprising wherein at least one of the first and second interface materials comprises at least one of thermal grease, thermal epoxy, polymer materials, phase-change materials, tin and indium.

33. The structure of claim 24 further comprising wherein the rotated alignment comprises wherein the apex is disposed at an angle with respect to at least one of the first and second interface materials, and wherein the angle is not substantially parallel to the first and second interface materials.

34. The structure of claim 33 further comprising wherein the angle comprises about a 10 to about a 80 degree angle.

35. The structure of claim 24 further comprising wherein the TIM comprises a portion of a package structure comprising a device.

36. The structure of claim 35 further comprising wherein the TIM is formed between a bottom portion of the device and a top portion of the package structure.

37. The structure of claim 35 wherein the TIM is formed between a top portion of the device and a bottom portion of an integrated heat structure disposed on the device.

38. The structure of claim 35 wherein the device comprises a microelectronic memory die.

39. The structure of claim 35 wherein the device comprises a central processing unit die.

40. The structure of claim 35 further comprising wherein the package structure comprises a portion of a coreless BBUL package.

41. The structure of claim 40 wherein the package structure further comprises at least one of a CPU and a memory die.

Assignees

• Intel Corp

Inventors

• Nardi Patrick
• Lofgreen Kelly P

Classifications

• F28F3/025

  the means being corrugated, plate-like elements · CPC title

• H10W72/9413

  on encapsulations · CPC title

• H10W72/874

  On different surfaces · CPC title

• H10W72/241

  Dispositions, e.g. layouts · CPC title

• H10W70/60

  Insulating or insulated package substrates; Interposers; Redistribution layers (leadframes H10W70/40) · CPC title