Gel-type thermal interface material
A thermal interface material that is useful in transferring heat from heat generating electronic devices, such as computer chips, to heat dissipating structures, such as heat spreaders and heat sinks. The thermal interface material includes at least one silicone oil, and at least one thermally conductive filler.
1. A thermal interface material comprising:
at least one low molecular weight silicone oil having a weight (M w ) average molecular weight less than 50,000 Daltons;
at least one thermally conductive filler; and
at least one high molecular weight silicone oil, wherein the high molecular weight silicone oil comprises a vinyl functional silicone oil having a weight (M w ) average molecular weight of at least 60,000 Daltons and having a kinematic viscosity of at least 100,000 cSt.
2. The thermal interface material of claim 1 , wherein the at least one low molecular weight silicone oil comprises a first silicone oil and a second silicone oil, wherein the first silicone oil is a vinyl functional silicone oil and the second silicone oil is a hydride functional silicone oil.
3. The thermal interface material of claim 1 , wherein the thermally conductive filler includes a first thermally conductive filler and a second thermally conductive filler, wherein the first thermally conductive filer is a metal oxide having a particle size greater than 1 micron and the second thermally conductive filler is a metal oxide having a particle size less than 1 micron.
4. The thermal interface material of claim 1 , wherein the thermally conductive filler includes a first thermally conductive filler, a second thermally conductive filler, and a third thermally conductive filler, wherein the first thermally conductive filler is a metal oxide having an average particle size greater than 10 microns, the second thermally conductive filler is a metal oxide having an average particle size between 1 micron and 10 microns, and the third thermally conductive filler is a metal oxide having an average particle size less than 1 micron.
5. The thermal interface material of claim 1 , wherein the thermal interface material comprises:
from 2 wt. % to 20 wt. % of the low molecular weight silicone oil;
from 50 wt. % to 95 wt. % of the thermally conductive filler; and
from 0.1 wt. % to 5 wt. % of the high molecular weight silicone oil.
6. The thermal interface material of claim 5 , wherein the low molecular weight silicone oil comprises a first silicone oil and a second silicone oil, wherein the first silicone oil is a vinyl functional silicone oil and the second silicone oil is a hydride functional silicone oil.
7. A thermal interface material comprising:
at least one high molecular weight vinyl functional silicone oil having a weight (M w ) average molecular weight of at least 60,000 Daltons and a kinematic viscosity of at least 100,000 cSt;
at least one low molecular weight silicone oil having a weight (M w ) average molecular weight less than 50,000 Daltons;
at least one thermally conductive filler; and
at least one addition inhibitor, wherein the addition inhibitor comprises an alkynyl compound.
8. The thermal interface material of claim 7 , wherein the addition inhibitor is selected from the group consisting of: a multivinyl functional polysiloxane, polydimethylsiloxane vinyl terminated in ethynyl cyclohexanol, 2-methyl-3-butyn-2-ol, and 3-methyl-1-pentyn-3-ol.
9. The thermal interface material of claim 7 , wherein the thermally conductive filler includes a first thermally conductive filler and a second thermally conductive filler, wherein the first thermally conductive filer is a metal having a particle size greater than 1 micron and the second thermally conductive filler is a metal oxide having a particle size less than 1 micron.
10. The thermal interface material of claim 9 , wherein a ratio of the first thermally conductive tiller to the second thermally conductive filler is from 1.5:1 to 3:1.
11. The thermal interface material of claim 7 , wherein the thermal interface material comprises:
from 2 wt. % to 20 wt. % of the silicone oils;
from 0.1 wt. % to 5 wt. % of a silane coupling agent;
from 50 wt. % to 95 wt. % of the thermally conductive filler; and
from 0.01 wt. % to 5 wt. % of the addition inhibitor.
12. The thermal interface material of claim 11 , wherein the addition inhibitor is polydimethylsiloxane vinyl terminated in ethynyl cyclohexanol.
13. An electronic component comprising:
a heat sink;
an electronic chip;
a thermal interface material having a first surface layer and a second surface layer, the thermal interface material positioned between the heat sink and electronic chip, the thermal interface material including:
at least one silicone oil having a kinematic viscosity of at least 100,000 cSt;
at least one thermally conductive filler; and
at least one addition inhibitor, wherein the addition inhibitor comprises an alkynyl compound, wherein the at least one silicone comprises at least one low molecular weight silicone oil and at least one high molecular weight silicone oil.
14. The electronic component of claim 13 , wherein the at least one high molecular weight silicone oil comprises a vinyl functional silicone oil having a weight (M w ) average molecular weight of at least 60,000 Daltons.
15. The electronic component of claim 13 , wherein the first surface layer is in contact with a surface of the electronic chip and the second surface layer is in contact with the heat sink.
16. The electronic component of claim 13 , wherein the electronic component further comprises a heat spreader positioned between the heat sink and the electronic chip, wherein the first surface layer is in contact with a surface of the electronic chip and the second surface layer is in contact with the heat spreader.
17. The electronic component of claim 13 , the electronic component further comprises a heat spreader positioned between the heat sink and the electronic chip, wherein the first surface layer is in contact with a surface of the heat spreader and the second surface layer is in contact with the heat sink.
18. The thermal interface of claim 1 , wherein the at least one high molecular weight silicone oil has a weight (M w ) average molecular weight of at least 1,000,000 Daltons and having a kinematic viscosity of at least 1,000,000 cSt.
19. The thermal interface of claim 1 , wherein the at least one low molecular weight silicone oil has a kinematic viscosity of less than 5,000 cSt.