Liquid metal TIM with STIM-like performance with no BSM and BGA compatible

Patent metadata

Field	Value
Publication number	US-11551994-B2
Application number	US-201816139401-A
Country	US
Kind code	B2
Filing date	Sep 24, 2018
Priority date	Sep 24, 2018
Publication date	Jan 10, 2023
Grant date	Jan 10, 2023

Abstract

Embodiments include an electronic system and methods of forming an electronic system. In an embodiment, the electronic system may include a package substrate and a die coupled to the package substrate. In an embodiment, the electronic system may also include an integrated heat spreader (IHS) that is coupled to the package substrate. In an embodiment the electronic system may further comprise a thermal interface pad between the IHS and the die. In an embodiment the die is thermally coupled to the IHS by a liquid metal thermal interface material (TIM) that contacts the thermal interface pad.

First claim

What is claimed is:

1. An electronic system, comprising:
a package substrate;
a die coupled to the package substrate;
an integrated heat spreader (IHS) coupled to the package substrate; and
a thermal interface pad between the IHS and the die, wherein the die is thermally coupled to the IHS by a liquid metal thermal interface material (TIM) that contacts the thermal interface pad, wherein the thermal interface pad comprises at least one of the elements that comprise the liquid metal TIM, and wherein the TIM comprises between 20 percent weight indium and 30 percent weight indium.

2. The electronic system of claim 1 , wherein the thermal interface pad is over and in contact with a surface of the die opposing the package substrate.

3. The electronic system of claim 1 , wherein the thermal interface pad is over and in contact with a surface of the IHS that faces the die.

4. The electronic system of claim 1 , further comprising:
a second thermal interface pad, wherein the second thermal interface pad is over and in contact with a surface of the die opposing the package substrate, and wherein the thermal interface pad is over and in contact with a surface of the IHS that faces the die.

5. The electronic system of claim 1 , wherein the liquid metal TIM wets an entire surface of the thermal interface pad.

6. The electronic system of claim 1 , wherein the thermal interface pad has a thickness less than 100 μm.

7. The electronic system of claim 1 , wherein the thermal interface pad has a thickness less than 50 μm.

8. The electronic system of claim 1 , wherein the liquid metal TIM has a melting temperature below 0° C.

9. The electronic system of claim 1 , wherein the liquid metal TIM comprises an alloy of two or more elements.

10. The electronic system of claim 9 , wherein the liquid metal TIM comprises gallium, indium, and tin.

11. The electronic system of claim 10 , wherein the thermal interface pad comprises indium.

12. An integrated heat spreader (IHS), comprising:
a main body;
a rim extending out from a first surface of the main body; and
a thermal interface pad encircled by the rim, wherein the thermal interface pad is over the main body, wherein the thermal interface pad comprises at least one of the elements that comprise a liquid metal TIM on the thermal interface pad, and wherein the TIM comprises between 20 percent weight indium and 30 percent weight indium.

13. The IHS of claim 12 , wherein a coating is formed over the main body, and wherein the thermal interface pad is in contact with the coating.

14. The IHS of claim 12 , wherein a thickness of the thermal interface pad is less than 100 μm.

15. The IHS of claim 14 , wherein the thickness of the thermal interface pad is less than 50 μm.

16. The IHS of claim 12 , wherein the rim is non-continuous around the thermal interface pad.

17. The IHS of claim 12 , further comprising a plurality of thermal interface pads.

18. The IHS of claim 12 , wherein the thermal interface pad is cold-pressed onto the IHS.

19. An electronic system, comprising:
a package substrate;
a die coupled to the package substrate;
an integrated heat spreader (IHS) coupled to the package substrate; and
a thermal interface material (TIM) between the die and the IHS, wherein the TIM comprises a first phase and a second phase, wherein the thermal interface pad comprises at least one of the elements that comprise the TIM, and wherein the TIM comprises between 20 percent weight indium and 30 percent weight indium.

20. The electronic system of claim 19 , wherein the first phase is liquid and the second phase is solid.

21. The electronic system of claim 19 , wherein the TIM comprises gallium and indium.

22. An electronic system, comprising:
a package substrate;
a die coupled to the package substrate;
an integrated heat spreader (IHS) coupled to the package substrate; and
a thermal interface material (TIM) between the die and the IHS, wherein the TIM comprises a first phase and a second phase, wherein the TIM comprises gallium and indium, and wherein the TIM comprises between 20 percent weight indium and 30 percent weight indium.

Assignees

• Intel Corp

Inventors

• Lofgreen Kelly
• Chiu Chia-Pin
• Petrini Joseph
• Cetegen Edvin
• Gebrehiwot Betsegaw
• Eid Feras

Classifications

• H10W72/90

  Bond pads, in general · CPC title

• H10W40/22

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

• H10W72/59

  Bond pads specially adapted therefor · CPC title

• H10W72/01925

  in solid form · CPC title

• H10W72/07336

  Soldering or alloying · CPC title