Conductive Ink Composition
A representative printable composition comprises a liquid or gel suspension of a plurality of conductive particles; a first solvent comprising a polyol or mixtures thereof, such as glycerin, and a second solvent comprising a carboxylic or dicarboxylic acid or mixtures thereof, such as glutaric acid. In various embodiments, the conductive particles are comprised of a metal, a semiconductor, an alloy of a metal and a semiconductor, or mixtures thereof, and may have sizes between about 5 nm to about 1.5 microns in any dimension. A representative conductive particle ink can be printed and annealed to produce a conductor.
1 . A composition comprising:
a plurality of conductive particles present in an amount of between 40% to 95% by weight of the composition;
a first solvent comprising glycerin and present in an amount of between 3.5% to 35% by weight of the composition; and
a second solvent comprising glutaric acid and present in an amount of between 0.5% to 15% by weight of the composition.
2 . The composition of claim 1 , further comprising:
a third, volatile solvent present in an amount of between 0.5% to 10% by weight of the composition.
3 . The composition of claim 1 , wherein the plurality of conductive particles have a size in any dimension between about 5 nm and about 1.0μ and are comprised of at least one metal selected from the group consisting of: aluminum, copper, silver, gold, nickel, palladium, tin, platinum, lead, zinc, bismuth, alloys thereof, and mixtures thereof.
4 . The composition of claim 3 , wherein at least some particles of the plurality of conductive particles are surface passivated to reduce oxidation.
5 . The composition of claim 3 , wherein at least some particles of the plurality of conductive particles are passivated with at least a partial coating selected from the group consisting of: benzotriazole, zinc phosphate, zinc dithiophosphate, tannic acid, hexafluoroacetylacetone, and mixtures thereof.
6 . The composition of claim 3 , further comprising:
an antioxidant selected from the group consisting of: N,N-diethylhydroxylamine, ascorbic acid, hydrazine, hexamine, phenylenediamine, and mixtures thereof.
7 . The composition of claim 1 , wherein the plurality of conductive particles have a size in any dimension between about 5 nm and about 1.5μ and are comprised of a semiconductor.
8 . The composition of claim 7 , wherein each particle of the plurality of conductive particles further comprises a doped semiconductor having a dopant selected from the group consisting of: boron, arsenic, phosphorus, gallium, and mixtures thereof.
9 . The composition of claim 7 , wherein each particle of the plurality of conductive particles comprises at least one semiconductor selected from the group consisting of: silicon, gallium arsenide (GaAs), gallium nitride (GaN), GaP, InAlGaP, InAlGaP, AlInGaAs, InGaNAs, AlInGASb, and mixtures thereof.
10 . The composition of claim 7 , wherein each particle of the plurality of conductive particles comprises at least one semiconductor selected from the group consisting of: silicon, germanium, and mixtures thereof; titanium dioxide, silicon dioxide, zinc oxide, indium-tin oxide, antimony-tin oxide, and mixtures thereof; II-VI semiconductors, which are compounds of at least one divalent metal (zinc, cadmium, mercury and lead) and at least one divalent non-metal (oxygen, sulfur, selenium, and tellurium) such as zinc oxide, cadmium selenide, cadmium sulfide, mercury selenide, and mixtures thereof; III-V semiconductors, which are compounds of at least one trivalent metal (aluminum, gallium, indium, and thallium) with at least one trivalent non-metal (nitrogen, phosphorous, arsenic, and antimony) such as gallium arsenide, indium phosphide, and mixtures thereof; and group IV semiconductors including hydrogen terminated silicon, carbon, germanium, and alpha-tin, and combinations thereof.
11 . The composition of claim 1 , wherein the plurality of conductive particles are comprised of metal particles and semiconductor particles, each having a size in any dimension between about 5 nm and about 200 nm.
12 . The composition of claim 1 , wherein the plurality of conductive particles are comprised of metal particles and semiconductor particles, each having a size in any dimension between about 1μ, and about 20μ.
13 . The composition of claim 1 , wherein each particle of the plurality of conductive particles comprises an alloy of a metal and a semiconductor, wherein the metal comprises at least one metal selected from the group consisting of: aluminum, copper, silver, gold, nickel, palladium, tin, platinum, lead, zinc, bismuth, alloys thereof, and mixtures thereof and wherein the semiconductor comprises at least one semiconductor selected from the group consisting of: silicon, gallium arsenide (GaAs), gallium nitride (GaN), GaP, InAlGaP, InAlGaP, AlInGaAs, InGaNAs, AlInGASb, and mixtures thereof.
14 . The composition of claim 1 , wherein the composition has a viscosity substantially between about 50 cps and about 25,000 cps at about 25° C.
15 . The composition of claim 1 , wherein the composition has a viscosity substantially between about 100 cps and about 10,000 cps at about 25° C.
16 . A method of using the composition of claim 1 , the method comprising:
printing and annealing the composition to form an electrical conductor.
17 . A composition comprising:
a plurality of metallic particles present in an amount of between 40% to 95% by weight of the composition;
a first solvent comprising glycerin and present in an amount of between 3.5% to 35% by weight of the composition;
a second solvent comprising glutaric acid and present in an amount of between 0.5% to 15% by weight of the composition; and
a third, volatile solvent comprising butanol and present in an amount of between 0.5% to 10% by weight of the composition.
18 . The composition of claim 17 , wherein the plurality of metallic particles have a size in any dimension between about 5 nm and about 1.0μ.
19 . The composition of claim 17 , wherein each particle of the plurality of metallic particles further comprises an alloy of a metal and a semiconductor, each alloyed metal and semiconductor nanoparticle of the plurality of metallic particles greater than or equal to 1 micron and less than or equal to 8 microns, comprising an alloy of at least one metal and at least one semiconductor.
20 . The composition of claim 19 , wherein the semiconductor comprises at least one semiconductor selected from the group consisting of: silicon, gallium arsenide (GaAs), gallium nitride (GaN), GaP, InAlGaP, InAlGaP, AlInGaAs, InGaNAs, AlInGASb, and mixtures thereof.
21 . The composition of claim 20 , wherein the semiconductor further comprises a dopant selected from the group consisting of: boron, arsenic, phosphorus, gallium, and mixtures thereof.
22 . The composition of claim 17 , wherein each particle of the plurality of metallic particles comprises at least one metal selected from the group consisting of:
aluminum, copper, silver, gold, nickel, palladium, tin, platinum, lead, zinc, bismuth, alloys thereof, and mixtures thereof.
23 . The composition of claim 17 , wherein at least some particles of the plurality of metallic particles are passivated with at least a partial coating selected from the group consisting of: benzotriazole, zinc phosphate, zinc dithiophosphate, tannic acid, hexafluoroacetylacetone, and mixtures thereof.
24 . The composition of claim 17 , further comprising:
an antioxidant selected from the group consisting of: N,N-diethylhydroxylamine, ascorbic acid, hydrazine, hexamine, phenylenediamine, and mixtures thereof.
25 . A composition comprising:
a plurality of alloyed metal and semiconductor nanoparticles, each alloyed metal and semiconductor nanoparticle of the plurality of alloyed metal and semiconductor nanoparticles greater than or equal to 1 micron and less than or equal to 8 microns, comprising an alloy of aluminum and silicon, present in an amount of between 40% to 95% by weight of the composition;
a first solvent comprising glycerin and present in an amount of between 3.5% to 35% by weight of the composition;
a second solvent comprising glutaric acid and present in an amount of between 0.5% to 15% by weight of the composition; and
a third, volatile solvent comprising butanol and present in an amount of between 0.5% to 10% by weight of the composition;
wherein the viscosity of the composition is substantially between about 50 cps to about 25,000 cps at 25° C.