Solder-carbon nanostructure composites and methods of making and using thereof
Solder-carbon nanostructure composites and methods of making and using thereof are described. Such composites can be useful for thermal application and can serve, for example, as thermal interface materials (TIMs).
1 . A solder-carbon nanostructure composite comprising:
a plurality of vertically aligned carbon nanotubes, having lengths in the range of 1-1000 microns, further comprising a metal coating thereon, and which are dispersed within and infiltrated by a solder material; and
wherein the plurality of vertically aligned carbon nanotubes is supported on or attached to a substrate;
wherein the plurality of vertically aligned carbon nanotubes have a density on the substrate surface that ranges from about 1×10 7 to 1×10 11 carbon nanotubes per mm 2 ;
wherein the substrate has a melting temperature that is higher than solder material's melting temperature;
wherein the plurality of vertically aligned carbon nanotubes comprises defects thereon due to exposure to a plasma treatment, an acid bath treatment, and/or due to the growth process of the plurality of vertically aligned nanotubes; and/or
wherein the plurality of vertically aligned carbon nanotubes comprises functional groups thereon due to a polymer wrapping the plurality of carbon nanotubes.
2 . The solder-carbon nanostructure composite of claim 1 , wherein the functional groups of the polymer wrapping the plurality of vertically aligned carbon nanotubes comprise phosphine, phosphonates, phosphonic acids, diphosphene, sulfonates, thiols, amines, amides, carboxylic acids, carboxylates, haloalkanes, hydroxyls, ethers, esters groups, or combinations thereof.
3 . The solder-carbon nanostructure composite of claim 1 , wherein the polymer coating comprises or consists of a polymeric material selected from non-conjugated polymers, conjugated polymers, or aromatic polymers.
4 . The solder-carbon nanostructure composite of claim 1 , wherein the polymer coating comprises or is formed of a thermoplastic elastomer selected from the group consisting of a polyester-based polyurethane, styrene-ethylene-butylene-styrene, polyimide, polyamide, silicone, polysiloxane, and blends thereof.
5 . The solder-carbon nanostructure composite of claim 1 , wherein the metal coating comprises one or more layers of a metal, metal alloy, or metal oxide, which increase the wettability and dispersibility of the carbon nanotubes in the solder material.
6 . The solder-carbon nanostructure composite of claim 1 , wherein the metal coating comprises one or more layers of a metal selected from aluminum, cobalt, chromium, zinc, tantalum, platinum, gold, nickel, iron, tin, lead, silver, titanium, indium, copper, alloys thereof, metal oxides, and combinations thereof, which increase the wettability and dispersibility of the carbon nanotubes in the solder material.
7 . The solder-carbon nanostructure composite of claim 1 , wherein the solder material comprises a metal selected from the group consisting of aluminum, bismuth, copper, cobalt, chromium, gallium, zinc, tantalum, platinum, gold, nickel, iron, tin, lead, silver, titanium, indium, and alloys thereof.
8 . The solder-carbon nanostructure composite of claim 1 , wherein the solder material is selected from the group consisting of a gold-tin solder, a tin-silver-copper solder, a tin-copper solder, a tin-lead solder, a tin-chrome solder a gallium solder, a gallium-indium-tin solder, and an indium solder.
9 . The solder-carbon nanostructure composite of claim 1 , wherein the plurality of vertically aligned carbon nanotubes dispersed within the solder material have a controlled alignment along the in-plane direction, cross-plane direction, or along an intermediate-plane direction.
10 . The solder-carbon nanostructure composite of claim 1 , wherein the solder-carbon nanostructure composite has an electrical conductivity which is at least about 105% higher than that of an electrical conductivity of a pristine solder material which does not contain any dispersed carbon nanotubes therein; and/or
wherein the composite has a thermal conductivity which is at least about 20% greater than that of a thermal conductivity a pristine solder material which does not contain any dispersed carbon nanotubes therein.
11 . The solder-carbon nanostructure composite of claim 1 , wherein the composite has a thermal resistance of less than about 0.1 cm 2 K/W; and/or
wherein the composite has a thermal conductivity in a range of between about 1-1000 W/m·K.
12 . The solder-carbon nanostructure composite of claim 1 , wherein the composite is a thermal interface material and the thermal interface material has a thermal resistance of less than about 0.1 cm 2 K/W.
13 . A method of making a solder-carbon nanostructure composite, the method comprising the steps of:
(1) forming or providing a carbon nanostructure array comprising a plurality of vertically aligned carbon nanotubes;
wherein the plurality of vertically aligned carbon nanotubes is supported on or attached to a substrate;
wherein the plurality of vertically aligned carbon nanotubes have a density on the substrate surface that ranges from about 1×10 7 to 1×10 11 carbon nanotubes per mm 2 ;
(2) optionally encapsulating the plurality of vertically aligned carbon nanotubes of the carbon nanostructure array in a suitable encapsulant, which is a polymer-based material;
(3) optionally exposing the optionally encapsulated carbon nanostructure array to a treatment that produces defect sites on the plurality of vertically aligned carbon nanotubes;
(4) optionally removing the encapsulant;
(5) depositing or forming a metal-based coating on the plurality of vertically aligned carbon nanotubes of the carbon nanostructure array of step (1);
(6) infiltrating the plurality of vertically aligned carbon nanotubes of the carbon nanostructure array of step (1) with a molten solder material;
wherein the substrate has a melting temperature that is higher than the temperature of the molten solder material and the substrate does not melt during the step of infiltrating;
(7) allowing the molten solder material to cool and solidify in order to form the solder-carbon nanostructure composite wherein the plurality of vertically aligned carbon nanotubes are dispersed within and infiltrated by the solidified solder material; and
(8) optionally encapsulating the solder-carbon nanostructure composite in a polymer.
14 . The method of claim 13 , wherein the polymer-based material is or comprises a polymeric material selected from non-conjugated polymers, conjugated polymers, or aromatic polymers.
15 . The method of claim 13 , wherein the polymer-based material is a coating comprising or formed of a polyester-based polyurethane, styrene-ethylene-butylene-styrene, polyimide, polyamide, silicone, polysiloxane, and blends thereof.
16 . The method of claim 13 , wherein the metal coating comprises one or more layers of a metal, metal alloy, or metal oxide, which increase the wettability and dispersibility of the carbon nanotubes in the molten solder material.
17 . The method of claim 13 , wherein the metal-based coating comprises one or more layers of a metal selected from aluminum, cobalt, chromium, zinc, tantalum, platinum, gold, nickel, iron, tin, lead, silver, titanium, indium, copper, alloys thereof, metal oxides, and combinations thereof, which increase the wettability and dispersibility of the carbon nanotubes in the molten solder material.
18 . The method of claim 13 , wherein the solder material comprises a metal selected from the group consisting of aluminum, bismuth, copper, cobalt, chromium, gallium, zinc, tantalum, platinum, gold, nickel, iron, tin, lead, silver, titanium, indium, and alloys thereof.
19 . The method of claim 13 , wherein the solder material is a gold-tin solder, a tin-silver-copper solder, a tin-copper solder, a tin-lead solder, a tin-chrome solder a gallium solder, a gallium-indium-tin solder or an indium solder.
20 . The method of claim 13 , wherein the treatment of step (3) is a plasma-based treatment or an acid bath treatment.
21 . The method of claim 13 , wherein the metal-based coating comprises one or more coatings formed of a metal, metal alloy, and/or a metal oxide.
22 . The method of claim 13 , wherein the metal-based comprises one or more coatings made of aluminum, bismuth, cobalt, chromium, zinc, gallium, tantalum, platinum, gold, nickel, iron, tin, lead, silver, tungsten, titanium, indium, copper, or combinations or alloys thereof and/or one or more metal oxides, such as oxides of the metals listed.
23 . The method of claim 13 , wherein the metal-based coating is selected to match the solder material's composition or to match at least one or more metals present in the solder material's composition.
24 . The method of claim 13 , wherein the metal-based coating has a thickness in a range from about 500 to 50,000 nanometers.
25 . The method of claim 13 , wherein the metal-based coating is formed by atomic layer deposition, chemical vapor deposition, or sputter coating the metal-based coating.
26 . The method of claim 13 , wherein the metal-based coating is formed by a wet coating method.
27 . The method of claim 26 , wherein the carbon nanotubes are infiltrated with a liquid phase containing metal precursors which are thermally or photonically decomposed to form and deposit elemental metal on the surface of carbon nanotubes.
28 . The method of claim 27 , wherein the metal precursors are selected from the group consisting of metal isopropoxides, metal hydrides, galistan, and metal salts.
29 . The method of claim 27 , wherein the metal isopropoxides are selected from the group consisting of copper (II) isopropoxide, vanadium (V) oxytriisopropoxide, and titanium (IV) isopropoxide.
30 . The method of claim 27 , wherein the metal salts are selected from the group consisting of silver nitrate, silver neodecanoate, silver oxalate, silver acetate, silver tartarate, silver hexafluoroacetylacetonate cyclooctadiene, copper acetate, copper formate tetrahydrate, copper formate, copper glycolate, copper lactate, copper oleate, copper hydroxide, nickel sulfate, and nickel acetate.
31 . The method of claim 27 , wherein the metal precursors are decomposed by placing the infiltrated array in a furnace and heating to a temperature of at least about 200° C.; optionally under an inert atmosphere of nitrogen or argon.
32 . The method of claim 13 , wherein the solder material is selected from the group consisting of aluminum, bismuth, copper, cobalt, chromium, gallium, zinc, tantalum, platinum, gold, nickel, iron, tin, lead, silver, titanium, indium, and alloys thereof.
33 . The method of claim 13 , wherein the solder material is selected from the group consisting of a gold-tin solder, a tin-silver-copper solder, a tin-copper solder, a tin-lead solder, a tin-chrome solder a gallium solder, a gallium-indium-tin solder or an indium solder.