Method for manufacturing metal wiring and kit

Abstract

Provided is a method for manufacturing a metal wiring in which a coating film remaining between metal wirings can be sufficiently removed in a developing step, and a kit. In a method for manufacturing a metal wiring according to one embodiment, a developing step includes a first developing treatment in which a region other than a dried coating film of a metal wiring is removed by a first developing solution, the first developing solution containing a solvent and an additive (A), the solvent being an organic solvent or water or a mixture thereof, the organic solvent being one or more selected from the group consisting of an alcohol solvent, a ketone solvent, an ester solvent, an amine solvent, and an ether solvent, and the concentration of the additive (A) in the first developing solution being 0.01% by mass or more and 20% by mass or less.

Description

Technical Field

[0001] This invention relates to a method for manufacturing metal wiring and a kit for manufacturing metal wiring. Background Technology

[0002] A circuit board has a structure in which conductive wiring is implemented on the substrate. The manufacturing method of a circuit board is generally as follows: First, a photoresist is coated on a substrate to which metal foil is bonded. Next, the photoresist is exposed and developed to obtain a negative shape of the desired circuit pattern. Then, the metal foil not covered by the photoresist is removed by chemical etching to form the pattern. This allows the manufacture of a high-performance conductive substrate.

[0003] However, previous methods have drawbacks such as numerous and complex steps, and the need for photoresist materials.

[0004] In contrast, direct wiring printing technology, which uses a dispersion (hereinafter also referred to as "paste material") formed by dispersing particles selected from the group consisting of metal particles and metal oxide particles, to directly print desired wiring patterns on a substrate, has attracted attention. This technology has fewer steps, does not require the use of photoresist materials, and has extremely high productivity.

[0005] As an example of direct printed wiring technology, there is a known method in which a paste material is coated on the entire surface of a substrate to form a coating film, and the coating film is selectively heat-fired by irradiating it with a laser in a patterned manner, thereby obtaining the desired wiring pattern (for example, see Patent Documents 1 and 2).

[0006] Patent document 2 describes that when a GaAlAs laser with a wavelength of 830 nm is used for illuminating, the diameter of the laser beam on the copper oxide film is 5 μm. The irradiated part is locally heated, which reduces the copper oxide and forms a reduced copper region with a diameter of approximately 5 μm.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: International Publication No. 2010 / 024385

[0010] Patent Document 2: Japanese Patent Application Publication No. 5-37126 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] As described above, when wiring is formed by laser irradiation, a coating remains in the areas not irradiated. This residual coating can cause problems such as metal growth outside the target wiring pattern and short circuits due to migration during plating operations after wiring formation. Therefore, after laser irradiation, the residual coating needs to be thoroughly removed by a development process.

[0013] Furthermore, applying physical force, such as by irradiating the developing solution with ultrasound during development, can improve the removal of residual coating. However, on the other hand, such physical force can damage the metal wiring, leading to problems such as wire breakage or increased resistance.

[0014] The present invention was made in view of the above-mentioned problems, and its object is to provide a method for manufacturing metal wiring that can fully remove the coating film remaining between metal wirings in the developing process, as well as a kit including a structure with a dried coating film and a developing solution, and a kit including a structure with a conductive part and a developing solution.

[0015] means for solving problems

[0016] The present invention includes the following methods.

[0017] [1] A method for manufacturing a metal wiring, the method comprising: a coating step, coating a dispersion comprising metal particles and / or metal oxide particles onto the surface of a substrate to form a dispersion layer; a drying step, drying the dispersion layer to form a structure having the substrate and a dried coating disposed on the substrate; a laser irradiation step, irradiating the dried coating with a laser to form a metal wiring; and a developing step, developing and removing areas of the dried coating other than the metal wiring using a developing solution, the developing step comprising a first developing treatment for developing and removing areas of the dried coating other than the metal wiring using a first developing solution, the first developing solution comprising a solvent and an additive (A), the solvent being an organic solvent or water or a mixture thereof.

[0018] The organic solvent is one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents.

[0019] The concentration of the additive (A) in the first developer is 0.01% by mass or more and 20% by mass or less.

[0020] [2] In the method for manufacturing metal wiring according to the above method 1, the arithmetic mean surface roughness Ra of the surface of the substrate is 70 nm or more and 1000 nm or less.

[0021] [3] The manufacturing method of the metal wiring according to method 1 or 2 above, wherein the additive (A) comprises a phosphorus-containing organic compound.

[0022] [4] The method for manufacturing metal wiring according to any one of the above methods 1 to 3, wherein the additive (A) is a dispersant.

[0023] [5] The method for manufacturing metal wiring according to any one of the above methods 1 to 4, wherein the developing step further includes a second developing process after the first developing process, in which the area other than the metal wiring of the dried coating is developed and removed by a second developing solution.

[0024] [6] A method for manufacturing a metal wiring, the method comprising: a coating step, coating a dispersion comprising metal particles and / or metal oxide particles and an additive (B) on the surface of a substrate to form a dispersion layer; a drying step, drying the dispersion layer to form a structure having the substrate and a dried coating disposed on the substrate; a laser irradiation step, irradiating the dried coating with a laser to form a metal wiring; and a developing step, developing and removing areas of the dried coating other than the metal wiring using a developing solution, wherein the developing step comprises a first developing treatment using a first developing solution and a second developing treatment using a second developing solution.

[0025] [7] In the method for manufacturing metal wiring according to method 5 or 6 above, the solubility of the metal particles and / or metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or metal oxide particles in the first developing solution.

[0026] [8] In the method for manufacturing metal wiring according to any one of the above methods 5 to 7, the solubility of copper oxide in the second developing solution is higher than that of copper oxide in the first developing solution.

[0027] [9] The method for manufacturing metal wiring according to any one of methods 5 to 8 above, wherein the solubility of copper oxide in the second developer is 0.1 mg / L or more and 10,000 mg / L or less.

[0028]

[10] The method for manufacturing metal wiring according to any one of the above methods 5 to 9, wherein the second developing solution contains one or more organic solvents selected from the group consisting of amine solvents, alcohol solvents, hydrocarbon solvents, ester solvents and ketone solvents.

[0029]

[11] In the method for manufacturing metal wiring according to the above method 10, the amine solvent comprises diethylenetriamine and / or 2-aminoethanol.

[0030]

[12] The method for manufacturing metal wiring according to any one of the above methods 1 to 11, wherein the first developing solution contains water and / or an alcohol solvent.

[0031]

[13] The method for manufacturing metal wiring according to any one of the above methods 1 to 12, wherein the first developing solution contains an additive (A) and the dispersion contains an additive (B), wherein the main component of the additive (A) is the same as the main component of the additive (B).

[0032]

[14] In the method for manufacturing metal wiring according to any one of the above methods 1 to 13, the difference between the surface free energy of the first developer and the surface free energy of the dispersion is 0 mN / m or more and 50 mN / m or less.

[0033]

[15] The method for manufacturing metal wiring according to any one of the above methods 1 to 14, wherein the method further includes a regenerated dispersion modulation step after the developing step, using the used developing solution to modulate the regenerated dispersion, and using the regenerated dispersion as the dispersion.

[0034]

[16] A kit comprising a structure with a dry coating and a first developer, wherein the structure with the dry coating has a substrate and a dry coating disposed on the surface of the substrate, the dry coating comprising (i) metal particles and / or metal oxide particles, and (ii) an additive (B), the first developer comprising the additive (A) and a solvent as an organic solvent or water or a mixture thereof, the organic solvent being one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents and ether solvents, and the concentration of the additive (A) in the first developer being 0.01% by mass or more and 20% by mass or less.

[0035]

[17] The kit according to method 16 above, wherein the additive (B) comprises a dispersant and / or a reducing agent.

[0036]

[18] The kit according to method 16 or 17 above, wherein the additive (A) comprises a dispersant.

[0037]

[19] The kit according to any one of the above methods 16 to 18, wherein the arithmetic mean surface roughness Ra of the surface of the structure with the dried coating is 70 nm or more and 1000 nm or less.

[0038]

[20] The kit according to any one of the above methods 16 to 19, wherein the kit further comprises a second developer.

[0039]

[21] A kit comprising a structure with a dry coating and a developer, wherein the structure with the dry coating has a substrate and a dry coating disposed on the surface of the substrate, the dry coating comprising metal particles and / or metal oxide particles and an additive (B), and the developer comprising a first developer and a second developer.

[0040]

[22] The kit according to method 20 or 21 above, wherein the solubility of copper oxide in the second developer is higher than the solubility of copper oxide in the first developer.

[0041]

[23] The kit according to any one of the above methods 20 to 22, wherein the solubility of copper oxide in the second developer is 0.1 mg / L or more and 10,000 mg / L or less.

[0042]

[24] The kit according to any one of the above methods 20 to 23, wherein the second developer contains one or more organic solvents selected from the group consisting of amine solvents, alcohol solvents, hydrocarbon solvents, ester solvents and ketone solvents.

[0043]

[25] The kit according to any one of the above methods 16 to 24, wherein the first developer contains water and / or an alcohol solvent.

[0044]

[26] The kit according to any one of the above methods 16 to 25, wherein the first developer contains an additive (A) and the dried coating contains an additive (B), wherein the main component of the additive (A) is the same as the main component of the additive (B).

[0045]

[27] A metal wiring manufacturing system comprising: a coating unit that coats a dispersion comprising metal particles and / or metal oxide particles and an additive (B) on the surface of a substrate to form a dispersion layer; a drying unit that dries the dispersion layer to form a structure having the substrate and a dried coating disposed on the substrate; a laser irradiation unit that irradiates the dried coating with a laser to form metal wiring; and a developing unit that develops and removes areas of the dried coating other than the metal wiring using a first developing solution, wherein the first developing solution comprises an additive (A) and a solvent as an organic solvent or water or a mixture thereof, the organic solvent being one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents and ether solvents, and the concentration of the additive (A) in the first developing solution being 0.01% by mass or more and 20% by mass or less.

[0046]

[28] A metal wiring manufacturing system comprising: a coating unit that coats a dispersion comprising metal particles and / or metal oxide particles and an additive (B) on the surface of a substrate to form a dispersion layer; a drying unit that dries the dispersion layer to form a structure having the substrate and a dried coating disposed on the substrate; a laser irradiation unit that irradiates the dried coating with a laser to form metal wiring; and a developing unit that develops and removes areas of the dried coating other than the metal wiring using a developing solution, wherein the developing unit comprises: a first developing unit that develops and removes areas of the dried coating other than the metal wiring using a first developing solution; and a second developing unit that develops and removes areas of the dried coating other than the metal wiring using a second developing solution.

[0047]

[29] In the metal wiring manufacturing system according to the above method 28, the solubility of copper oxide in the second developer is higher than that of copper oxide in the first developer.

[0048]

[30] The metal wiring manufacturing system according to method 28 or 29 above, wherein the first developing solution contains water and / or alcohol solvent and additive (A) of 0.01% by mass and 20% by mass or less.

[0049]

[31] The metal wiring manufacturing system according to method 27 or 30 above, wherein the main component of the additive (A) is the same as the main component of the additive (B).

[0050] Invention Effects

[0051] According to one aspect of the present invention, a method for manufacturing metal wiring in which the coating remaining between metal wirings can be sufficiently removed during the developing process can be provided, as well as a kit comprising a structure with a dried coating and a developing solution, and a kit comprising a structure with conductive parts and a developing solution. Attached Figure Description

[0052] Figure 1 This is an explanatory diagram illustrating an example of a method for manufacturing metal wiring according to this embodiment.

[0053] Figure 2 This is a schematic diagram illustrating the overlapping irradiation of lasers in the manufacturing method of the metal wiring of this embodiment.

[0054] Figure 3 This is a schematic diagram illustrating an example of a fixture for holding a structure with conductive parts during the developing process of the metal wiring manufacturing method of this embodiment.

[0055] Figure 4This is a schematic diagram illustrating an example of a fixture for holding a structure with conductive parts during the developing process of the metal wiring manufacturing method of this embodiment.

[0056] Figure 5 This is a schematic diagram illustrating an example of a fixture for holding a structure with conductive parts during the developing process of the metal wiring manufacturing method of this embodiment.

[0057] Figure 6 This is an explanatory diagram illustrating an example of reusing used developer in the manufacturing method of metal wiring according to this embodiment.

[0058] Figure 7 This is an explanatory diagram illustrating an example of the process flow in the method for manufacturing metal wiring according to this embodiment, where the used developer is reused.

[0059] Figure 8 This is an explanatory diagram illustrating an example of the metal wiring manufacturing system of this embodiment. Detailed Implementation

[0060] Hereinafter, one embodiment of the present invention (hereinafter referred to as "this embodiment") will be described in detail.

[0061] <Metal wiring manufacturing method>

[0062] In this embodiment, the method for manufacturing metal wiring includes: a coating step, in which a dispersion containing metal particles and / or metal oxide particles is coated on the surface of a substrate to form a dispersion layer; a drying step, in which the dispersion layer is dried to form a structure having a substrate and a dried coating disposed on the substrate; a laser irradiation step, in which a laser is irradiated onto the dried coating to form metal wiring; and a developing step, in which the area of ​​the dried coating other than the metal wiring is developed and removed using a developing solution.

[0063] The inventors have addressed the issue that when a laser-irradiated area (hereinafter, sometimes referred to as an exposed area) in a dry coating disposed on a substrate is formed into a metal wiring, and the un-irradiated area (hereinafter, sometimes referred to as an unexposed area) of the dry coating is removed by developing with a developing solution, there are instances where the unexposed area cannot be sufficiently removed by the developing solution, and where the metal wiring is damaged or peeled off due to development. The inventors have conducted various studies on methods to avoid these problems and have found that by controlling the composition of the developing solution, good development and removal of the unexposed area can be achieved.

[0064] In a first embodiment, the developing step includes a first developing process that uses a first developing solution to develop and remove areas other than the metal wiring of the dried coating. In one embodiment, the first developing solution comprises a solvent, such as an organic solvent or water or a mixture thereof, and an additive (A). In one embodiment, the organic solvent is one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents. In one embodiment, the concentration of additive (A) in the first developing solution of the first embodiment is 0.01% by mass or more and 20% by mass or less.

[0065] In a second approach, the developing process includes a first developing treatment using a first developing solution and a second developing treatment using a second developing solution. In one approach, the first developing solution involved in the second approach comprises water and / or an alcohol solvent. In one approach, the second developing solution involved in the second approach comprises an organic solvent.

[0066] [Composition of the developer]

[0067] (First method)

[0068] In the first method, at least a first developer is used as the developer. The first developer in one method comprises a solvent (A) as an organic solvent, water, or a mixture thereof, and is composed of these components. In one method, the organic solvent contained in the first developer is one or more solvents selected from alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents.

[0069] The solvent may be a combination of one or more solvents, preferably including a polar solvent, and more preferably composed of a polar solvent. Polar solvents are particularly advantageous in terms of developability due to their excellent dispersibility of metal particles and / or metal oxide particles. The solvent contained in the developer (which may be a combination of one or more solvents) preferably contains at least one compound of the same kind as the dispersion medium contained in the dispersion (which may be a combination of one or more solvents), or is composed of a compound of the same kind as the dispersion medium.

[0070] Alcohol solvents are compounds containing an alcoholic hydroxyl group. Examples of alcohol solvents include monohydric alcohols, dihydric alcohols, and trihydric alcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, sec-pentanol, tert-pentanol, 2-methylbutanol, 2-ethylbutanol, 3-methoxybutanol, n-hexanol, sec-hexanol, 2-methylpentanol, sec-heptanol, 3-heptanol, n-octanol, sec-octanol, 2-ethylhexanol, n-nonanol, and 2,6-dimethyl- 4-Heptanol, n-Decanol, Cyclohexanol, Methylcyclohexanol, 3,3,5-Trimethylcyclohexanol, Phenol, Benzyl alcohol, Diacetone alcohol, Ethylene glycol, 1,2-Propanediol, 1,3-Butanediol, 2-Pentanediol, 2-Methylpentane-2,4-diol, 2,5-Hexanediol, 2,4-Heptanediol, 2-Ethylhexane-1,3-diol, Diethylene glycol, Dipropylene glycol, Hexanediol, Octanediol, Triethylene glycol, Tris-1,2-Propanediol, etc. The alcohol solvent can be an alcohol ester, alcohol ether, etc. For example:

[0071] As ether solvents, the alcohol ethers exemplified below are ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, and other glycol ethers.

[0072] Propylene glycol monomethyl ether acetate and other glycol esters;

[0073] These are also included in alcohol solvents.

[0074] Examples of ketone solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and cyclohexanone.

[0075] Examples of ester solvents include carboxylic acid esters, such as methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, methoxybutyl acetate, amyl acetate, n-propyl acetate, isopropyl acetate, methyl lactate, ethyl lactate, and butyl lactate. In one embodiment, the ester may be an alkyl carboxylic acid ester, and the alkyl group may be substituted or unsubstituted.

[0076] Amine solvents are compounds containing an amino group, and examples include primary amines, secondary amines, tertiary amines, alkanolamines, and amides. Examples of amine solvents include diethylenetriamine, 2-aminoethanol, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, N-methylethanolamine, N-methyldiethanolamine, dicyclohexylamine, n-methyl-2-pyrrolidone, and N,N-dimethylformamide.

[0077] Examples of ether solvents include diethyl ether, diisopropyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, 1,4-diepoxide, vinyl ethylene carbonate, and tetrahydrofuran.

[0078] In a preferred embodiment, the solvent in the first developer comprises water and / or an alcohol solvent, or water and / or an alcohol solvent. Water and alcohol solvents are solvents capable of effectively dispersing additive (A). By including additive (A) in the first developer, the redispersibility and / or solubility of particles on the substrate can be improved, resulting in good particle development. Particularly when additive (A) comprises a dispersant or is a dispersant, the redispersibility of particles on the substrate becomes even better, thus making it suitable for dispersing metal particles and / or metal oxide particles attached to the substrate into the developer. From the viewpoint of improving polarity, the solvent in the first developer preferably comprises one or more selected from water, ethanol, n-propanol, isopropanol, butanol, heptanol, and octanol, and is particularly preferred to consist of one or more of these.

[0079] The water content in the first developer may be 10% or more by mass, or 20% or more by mass, or 30% or more by mass in one method, or 99.99% or less by mass, or 99.9% or less by mass, or 99% or less by mass, or 98% or less by mass, or 97% or less by mass in another method.

[0080] The alcohol solvent content in the first developer may be 10% or more by mass, or 20% or more by mass, or 30% or more by mass in one method, or 99.99% or less by mass, or 99.9% or less by mass, or 99% or less by mass, or 98% or less by mass, or 97% or less by mass in another method.

[0081] In one embodiment, the total content of water and alcohol solvent in the first developer may be 20% by mass or more, or 40% by mass or more, or 50% by mass or more, or 60% by mass or more, or 70% by mass or more, or 80% by mass or more, or 85% by mass or more, or 90% by mass or more. In another embodiment, the total content may be less than 100% by mass, or less than 99.99% by mass, or less than 99.9% by mass, or less than 99.5% by mass, or less than 99% by mass, or less than 98% by mass, or less than 97% by mass.

[0082] The solvent content in the first developer can be 20% by mass or more, or 40% by mass or more, or 50% by mass or more, or 60% by mass or more, or 70% by mass or more, or 80% by mass or more, or 85% by mass or more, or 90% by mass or more in one embodiment. In another embodiment, the total content can be less than 100% by mass, or less than 99.99% by mass, or less than 99.9% by mass, or less than 99.5% by mass, or less than 99% by mass, or less than 98% by mass, or less than 97% by mass.

[0083] In one embodiment, the additive (A) is one or more selected from the group consisting of surfactants, dispersants, reducing agents, and complexing agents. Regarding the content of additive (A) in the first developing solution, from the viewpoint of effectively improving developability by enhancing the redispersibility and / or solubility of particles on the substrate, in one embodiment it is 0.01% by mass or more, or 0.1% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more; from the viewpoint of suppressing the dissolution of metal wiring caused by additive (A), from the viewpoint of forming a low-viscosity developing solution suitable for development even when using a high-viscosity additive (A), and from the viewpoint of preventing excess additive (A) from adhering to the substrate and metal wiring and simplifying the post-development washing process, in one embodiment it is 20% by mass or less, or 15% by mass or less, or 10% by mass or less.

[0084] In one embodiment, additive (A) comprises or is a surfactant. There are no particular limitations on the surfactant; for example, anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, polymeric surfactants, etc., can be used.

[0085] Examples of anionic surfactants include: fatty acid salts such as sodium lauryl sulfate; higher alcohol sulfates; alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate; polyoxyethylene alkyl ether sulfates, polyoxyethylene polycyclic phenyl ether sulfates, polyoxynonyl phenyl ether sulfonates, polyoxyethylene-polyoxypropylene glycol ether sulfates, etc.; and so-called reactive surfactants that have sulfonic acid groups or sulfate groups and polymerizable unsaturated double bonds in their molecules.

[0086] Examples of cationic surfactants include alkylamine salts and quaternary ammonium salts.

[0087] Examples of amphoteric surfactants include cocamidopropyl betaine, cocamidopropyl hydroxysulfonate betaine, lauryl dimethylaminoacetic acid betaine, stearyl dimethylaminoacetic acid betaine, dodecylaminomethyl dimethylsulfonate propyl betaine, octadecylaminomethyl dimethylsulfonate propyl betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethyl imidazoline betaine, alkyl diaminoethyl glycine hydrochloride, alkyl polyaminoethyl glycine, sodium lauroyl glutamate, potassium lauroyl glutamate, N-alkyl aminopropyl glycine, and alkyl dimethylamine oxide.

[0088] Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene nonylphenyl ethers, sorbitan fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene-polyoxypropylene block copolymers, or reactive nonionic surfactants that have their backbone and polymerizable unsaturated double bonds in their molecules.

[0089] Examples of high molecular weight surfactants include polyvinyl alcohol, which can be modified.

[0090] From the viewpoint of improving the redispersibility and / or solubility of particles on the substrate, the content of surfactant in the first developer is preferably 0.01% by mass or more, or 0.1% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more. From the viewpoint of preventing excess surfactant from adhering to the substrate and metal wiring and simplifying the water washing process after development, it is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less.

[0091] In one embodiment, additive (A) comprises or is a dispersant. The dispersant effectively disperses the coating components of the dried coating (especially metal particles and / or metal oxide particles that are difficult to remove through development) in the developer, thus enabling good development even with solvents that are unlikely to damage the metal wiring and substrate, such as organic solvents selected from the group consisting of alcohols, ketones, esters, amines, and ethers, and / or water. In other words, a developer containing a dispersant helps to balance avoiding damage to the metal wiring with good developability.

[0092] Dispersants enable the efficient dispersion (i.e., efficient removal) of metal particles and / or metal oxide particles adhering to a substrate in the developing solution. As a dispersant, the dispersants that may be included in the dispersion of the present invention are preferably those described later in the section on [Composition of Dispersion and Dry Coating]. For example, if a phosphorus-containing organic compound is used, the metal particles and / or metal oxide particles (especially copper oxide particles) are well dispersed in the developing solution, thus facilitating development. Therefore, in one embodiment, preferred examples of dispersant compounds in the developing solution are the same as those described later in the section on [Composition of Dispersion and Dry Coating].

[0093] The number-average molecular weight of the dispersant is not particularly limited, but is preferably 300 to 300,000, more preferably 300 to 30,000, and even more preferably 300 to 10,000. If the number-average molecular weight is 300 or higher, there is a tendency for increased dispersion stability of the developer. Furthermore, if it is 300,000 or lower, especially 30,000 or lower, the amount of dispersant residue after development is less, which can reduce the resistance of the metal wiring. It should be noted that in this invention, the number-average molecular weight is a value obtained by conversion using gel permeation chromatography with standard polystyrene.

[0094] As additive (A), particularly dispersant, phosphorus-containing organic compounds are preferred from the viewpoint of excellent dispersibility of metal particles and / or metal oxide particles. Furthermore, additive (A), particularly dispersant, is preferred from the viewpoint of adsorbing onto metal particles and / or metal oxide particles and suppressing particle aggregation through steric hindrance, having groups (e.g., hydroxyl groups) that are compatible with these particles. It is particularly preferred to use metal oxide particles and hydroxyl-containing dispersants together. Additive (A), particularly dispersant, preferably comprises a phosphorus-containing organic compound. A particularly preferred example of additive (A), particularly dispersant, is a phosphorus-containing organic compound having a phosphate group.

[0095] Phosphorus-containing organic compounds are preferably easily decomposed or evaporated by light and / or heat. By using organic materials that are easily decomposed or evaporated by light and / or heat, it is less likely that organic residue will remain after firing, resulting in metal wiring with low resistivity.

[0096] The decomposition temperature of phosphorus-containing organic compounds is not limited, but is preferably below 600°C, more preferably below 400°C, and even more preferably below 200°C. From the viewpoint of the stability of phosphorus-containing organic compounds, the decomposition temperature can preferably be above 60°C, above 90°C, or above 120°C. It should be noted that in this invention, the decomposition temperature is the value of the decomposition onset temperature determined by thermogravimetric differential thermal analysis.

[0097] The boiling point of phosphorus-containing organic compounds under normal pressure is not limited, but is preferably below 300°C, more preferably below 200°C, and even more preferably below 150°C. From the viewpoint of the stability of phosphorus-containing organic compounds, the boiling point can preferably be above 60°C, above 90°C, or above 120°C.

[0098] The absorption characteristics of phosphorus-containing organic compounds are not limited, but those capable of absorbing the laser used in the firing process are preferred. It should be noted that, in this invention, "capable of absorbing the laser used in the firing process" refers to an absorption coefficient of 0.10 cm⁻¹ at a wavelength of 532 nm, measured using a UV-Vis spectrophotometer. -1 That's all. More specifically, it is preferable to absorb light with a light emission wavelength (center wavelength) of 355nm, 405nm, 445nm, 450nm, 532nm, 1064nm, etc. (i.e., an absorption coefficient of 0.10cm at that wavelength) that is used as the laser emission wavelength (center wavelength) in the firing process. -1 Phosphorus-containing organic compounds (as described above). In particular, when the substrate is a resin substrate, phosphorus-containing organic compounds that absorb light with a center wavelength of 355 nm, 405 nm, 445 nm and / or 450 nm are preferred.

[0099] From the viewpoint of improving the atmospheric stability of the developer, phosphorus-containing organic compounds are preferred as phosphate esters. For example, the following general formula (1):

[0100] [Chemical Formula 1]

[0101]

[0102] (In the formula, R is a monovalent organic group.)

[0103] The phosphate monoester shown exhibits excellent adsorption of metal oxide particles and moderate adhesion to the substrate, thus contributing to both stable formation of metal wiring and good development of unexposed areas, which is preferable. Examples of R include substituted or unsubstituted hydrocarbon groups.

[0104] As an example of a phosphate monoester, compounds having the structure represented by the following formula (2) can be listed:

[0105] [Chemical Formula 2]

[0106]

[0107] In addition, as an example of a phosphate monoester, compounds having the structure represented by the following formula (3) can be listed:

[0108] [Chemical Formula 3]

[0109]

[0110] (In the formula, l, m, and n are each an independent integer from 1 to 20.)

[0111] In the above formula (3), l is an integer from 1 to 20, preferably an integer from 1 to 15, more preferably an integer from 1 to 10, m is an integer from 1 to 20, preferably an integer from 1 to 15, more preferably an integer from 1 to 10, and n is an integer from 1 to 20, preferably an integer from 1 to 15, more preferably an integer from 1 to 10.

[0112] As an organic compound containing phosphorus, the organic structure can be derived from polyethylene glycol (PEG), polypropylene glycol (PPG), polyimide, polyester (e.g., polyethylene terephthalate (PET), polyethylene naphthalate (PEN)), polyethersulfone (PES), polycarbonate (PC), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polyacetal, polyaryl ester (PAR), polyamide (PA), polyamide-imide (PAI), polyether-imide (PEI), polyphenylene ether (PPE), polyphenylene sulfide (PPS), polyetherketone (PEK), polyphthalamide (PPA), polyether nitrile (PENt), polybenzimidazole (PBI), polycarbodiimide, polysiloxane, polymethacrylamide, nitrile rubber, acrylic rubber, polytetrafluoroethylene, etc. The structures of compounds such as epoxy resin, phenolic resin, melamine resin, urea resin, polymethyl methacrylate resin (PMMA), polybutene, polypentene, ethylene-propylene copolymer, ethylene-butene-diene copolymer, polybutadiene, polyisoprene, ethylene-propylene-diene copolymer, butyl rubber, polymethylpentene (PMP), polystyrene (PS), styrene-butadiene copolymer, polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polyether ether ketone (PEEK), phenolic varnish, benzocyclobutene, polyvinylphenol, polychloroprene, polyoxymethylene, polyoxymethylene (PSF), polysulfone (PSF), polysulfide, silicone resin, aldose, cellulose, linear starch, dextrin, dextran, fructan, etc. (specifically, structures that have undergone functional group modification, functional group alteration, or polymerization). Phosphorus-containing organic compounds with a polymer backbone selected from polyethylene glycol, polypropylene glycol, polyacetal, polybutene, and polysulfides are easily decomposed and do not leave residues in the metal wiring obtained after firing, and are therefore preferred.

[0113] As a specific example of phosphorus-containing organic compounds, commercially available materials can be used; specifically, BYK-Chemie can be cited. DISPERBYK (registered trademark)-102, DISPERBYK-103, DISPERBYK-106, DISPERBYK-109, DISPERBYK-110, DISPERBYK-111, DISPERBYK-118, DISPERBYK-140, DISPERBYK-145, DISPERBYK-168, DISPERBYK -180, DISPERBYK-182, DISPERBYK-187, DISPERBYK-190, DISPERBYK-191, DISPERBYK-193, DISPERBYK-194N, DISPERBYK-199, DISPERBYK-2000, DISPERBYK-2001, DISPERBYK-2008, DISPERBYK D ISPERBYK-2061, DISPERBYK-2164, DISPERBYK-2096, DISPERBYK-2200, BYK (registered trademark)-405, BYK-607, BYK-9076, BYK-9077, BYK-P105, and PLYSURF (registered trademark) M208F and PLYSURFDBS manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd. These materials can be used alone or in combination.

[0114] The dispersant in the first developing solution is particularly preferably a phosphorus-containing organic compound, which is further preferably the same as the phosphorus-containing organic compound contained in the dispersion. By making them the same, the redispersion of particles on the substrate becomes better.

[0115] Regarding the content of dispersant in the first developing solution, from the perspective of enabling efficient dispersion (i.e. efficient removal) of metal particles and / or metal oxide particles adhering to the substrate in the developing solution, it is preferably 0.01% by mass or more, 0.1% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more. From the perspective of being able to suppress the dissolution of metal wiring caused by dispersant, from the perspective of being able to form a low-viscosity developing solution suitable for development even when using a high-viscosity dispersant, and from the perspective of being able to prevent excess dispersant from adhering to the substrate and metal wiring and simplifying the water washing process after development, it is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less.

[0116] In one embodiment, additive (A) comprises or is a reducing agent. The reducing agent preferably contains hydrazine and / or hydrazine hydrate, more preferably hydrazine and / or hydrazine hydrate. The inclusion of a reducing agent in the first developing solution is advantageous in that it enables the efficient dispersion and / or dissolution (i.e., efficient removal) of metal particles and / or metal oxide particles adhering to the substrate in the developing solution.

[0117] From the viewpoint of improving the redispersibility and / or solubility of particles on the substrate, the content of reducing agent in the first developer is preferably 0.01% by mass or more, or 0.1% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more. From the viewpoint of preventing excess reducing agent from adhering to the substrate and metal wiring and simplifying the water washing process after development, the content of reducing agent in the first developer is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less.

[0118] In one embodiment, additive (A) comprises or is a complexing agent. Examples of complexing agents include: carboxylic acids such as citric acid, glycolic acid, tartaric acid, malic acid, lactic acid, and gluconic acid; amino acids such as glycine; ketones such as acetylacetone; amines such as ethylenediamine and diethylenetriamine; nitrogen-containing heterocyclic compounds such as pyridine, 2,2'-bipyridine, and 1,10-phenanthroline; and amino polycarboxylic acids such as hypozinotriacetic acid and ethylenediaminetetraacetic acid. The inclusion of a complexing agent in the first developer is advantageous in that it enables the efficient dissolution (i.e., efficient removal) of metal particles and / or metal oxide particles adhering to the substrate in the developer.

[0119] From the viewpoint of improving the redispersibility and / or solubility of particles on the substrate, the content of the complexing agent in the first developer is preferably 0.01% by mass or more, or 0.1% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more. From the viewpoint of reducing damage to metal wiring, the content of the complexing agent in the first developer is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less.

[0120] Preferably, the additive (A) in the first developer and the additive (B) in the dispersion contain the same main component (i.e., the component contained in the largest quantity by weight in each additive). By making the main components of additive (A) and additive (B) the same, the redispersion of particles on the substrate becomes better. In particular, from the viewpoint of excellent dispersibility of metal particles and / or metal oxide particles, additive (A) and additive (B) are further preferred to be phosphorus-containing organic compounds.

[0121] In the first approach, a second developer may be used in addition to the first developer. Furthermore, an additional developer may be used in addition to the first and second developers. The first, second, and additional developers may have the same composition, but are preferably different compositions. In one approach, the developer is a combination of a first developer containing a solvent (an organic solvent or water, or a mixture thereof) and an additive (A), and a second developer containing an organic solvent. Organic solvents can dissolve and remove metals or metal oxides, thus preventing metal residues in the wiring, making them particularly suitable for fine-finishing development. From this viewpoint, it is advantageous to use the aforementioned combination of developers in a approach that involves a first development process using the first developer followed by a second development process using the second developer. As a specific example of the second developer and the organic solvent it may contain, a developer identical to the second developer of the second approach described later can be exemplified. As an additional developer, a developer preferably containing the same organic solvent as the organic solvent used in the second developer, but with a higher solubility for copper oxide than the second developer, is preferred. Alternatively, as an additional developer, a developer identical to the second developer involved in the second approach can be exemplified.

[0122] (Second method)

[0123] In the second approach, at least a first developer and a second developer are used as the developing solution. In one approach, the first developer involved in the second approach comprises water and / or an alcohol solvent. The first developer involved in the second approach comprises water and / or an alcohol solvent, and an additive (A), or is composed of them. As specific examples of the type and amount of the alcohol solvent and the additive (A), the same specific examples as those exemplified with respect to the first developer of the first approach can be given.

[0124] In one approach, the second developer involved in the second approach may have the same composition as the first developer involved in the first approach.

[0125] In another embodiment, the second developing solution involved in the second embodiment contains an organic solvent. Organic solvents can dissolve and remove metals or metal oxides, thus preventing metal residues between wirings, and are particularly suitable for fine-finishing development. As organic solvents, amine solvents, alcohol solvents, hydrocarbon solvents, ester solvents, and ketone solvents are preferred, and one or more of them may be used. Amine solvents are particularly preferred as organic solvents.

[0126] Examples of amine solvents include amines (primary, secondary, and tertiary amines), alkanolamines, amides, etc. More specifically, examples include diethylenetriamine, 2-aminoethanol, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, N-methylethanolamine, N-methyldiethanolamine, dicyclohexylamine, n-methyl-2-pyrrolidone, N,N-dimethylformamide, etc.

[0127] Examples of alcohol solvents include monohydric or polyhydric alcohols, as well as ethers and esters of such alcohols. Diols are preferred. More specific examples of alcohols include:

[0128] Methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, sec-pentanol, tert-pentanol, 2-methylbutanol, 2-ethylbutanol, 3-methoxybutanol, n-hexanol, sec-hexanol, 2-methylpentanol, sec-heptanol, 3-heptanol, n-octanol, sec-octanol, 2-ethylhexanol, n-nonanol, 2,6-dimethyl-4-heptanol, n-decanol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, phenol, benzyl alcohol, diacetone alcohol, and other monohydric alcohols;

[0129] Ethylene glycol, 1,2-propanediol, 1,3-butanediol, 2-pentanediol, 2-methylpentane-2,4-diol, 2,5-hexanediol, 2,4-heptanediol, 2-ethylhexane-1,3-diol, diethylene glycol, dipropylene glycol, hexanediol, octanediol, triethylene glycol, tri-1,2-propanediol, and other diols;

[0130] Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, and other glycol ethers;

[0131] Propylene glycol monomethyl ether acetate and other glycol esters, etc.

[0132] Examples of hydrocarbon solvents include pentane, hexane, octane, nonane, decane, cyclohexane, methylcyclohexane, toluene, xylene, mesitylene, and ethylbenzene.

[0133] Examples of ester solvents include 3-methoxy-3-methyl-butyl acetate, ethoxyethyl propionate, ethyl glycerol, n-propyl acetate, and isopropyl acetate.

[0134] Examples of ketone solvents include methyl ethyl ketone, methyl isobutyl ketone, and dimethyl carbonate.

[0135] From the viewpoint of developability, amine solvents are particularly preferred as organic solvents, specifically diethylenetriamine, 2-aminoethanol, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, N-methylethanolamine, N-methyldiethanolamine, dicyclohexylamine, n-methyl-2-pyrrolidone, N,N-dimethylformamide, etc. From the viewpoint of developability, at least one of diethylenetriamine and 2-aminoethanol is particularly preferred.

[0136] In one embodiment, organic solvents may also function as additives (A) and / or additives (B) of the present invention. For example, diethylenetriamine is an organic solvent and may also function as a complexing agent. The amount of such components present in the developer is included in both the content of the organic solvent and the content of the additives.

[0137] In one embodiment, the organic solvent content in the second developer may be 1% or more by mass, or 2% or more by mass, or 3% or more by mass. In one embodiment, this content may be 100% by mass, or in another embodiment, it may be 98% or less by mass, or 97% or less by mass, or 95% or less by mass. In this case, as a balance, water and / or the additive (A) of the present invention (e.g., a dispersant) may be included. On the other hand, in one embodiment, the second developer may not contain additive (A). In one embodiment, the second developer is an organic solvent, or a mixture of an organic solvent and water.

[0138] In one embodiment, the water content in the second developer may be 1% or more by mass, or 2% or more by mass, or 3% or more by mass, or 100% by mass, or less than 99% by mass, or less than 98% by mass, or less than 95% by mass.

[0139] In the second approach, from the viewpoint of excellent redispersibility of metal particles and / or metal oxide particles, the additive (A) in the first developer is preferably a dispersant, and particularly preferably a phosphorus-containing organic compound. Furthermore, from the viewpoint of improving the redispersibility of particles on the substrate, it is particularly preferable that the first developer and the dispersion contain the same phosphorus-containing organic compound. By improving the dispersibility of particles in the first developer, the developing effect in the second developer becomes better.

[0140] In the second approach, it is preferable that the additive (A) contained in the first developing solution has the same main component (i.e., the component contained in the largest quantity by mass) as the additive (B) contained in the dispersion. By making the main components of additive (A) and additive (B) the same, the redispersibility of particles on the substrate is improved. In particular, from the viewpoint of good dispersibility of metal particles and / or metal oxide particles, it is further preferred that additive (A) and additive (B) be phosphorus-containing organic compounds.

[0141] (Solubility)

[0142] In both the first and second methods, it is preferable that the solubility of metal particles and / or metal oxide particles in the second developing solution is higher than that in the first developing solution. It should be noted that the aforementioned solubility values ​​are measured using inductively coupled plasma (ICP) luminescence analysis. Specific details are as follows.

[0143] Add 0.10 g of powdered metal particles and / or metal oxide particles to 40 ml of developing solution and let stand at room temperature (25°C) for 6 hours. Then, filter the developing solution containing the powder through a 0.2 μm filter and dilute 100-fold with 0.10 mol / L nitric acid. Measure the metal concentration (mg / L) of the diluted solution using an ICP-emitting diode (ICP-LED) apparatus (e.g., SII Nanotechnology). Calculate the concentration of the metal particles and / or metal oxide particles (mg / L) from the metal concentration, which is used as the solubility of the metal particles and / or metal oxide particles.

[0144] Based on the solubility described above, after development with the first developer, development is performed with the second developer, thereby obtaining good development and removal efficiency of metal particles and / or metal oxide particles attached to the substrate.

[0145] It is particularly preferred that the solubility of metal particles and / or metal oxide particles in the second developing solution is higher than that in the first developing solution. The first developing solution contains water and / or an alcohol solvent, and an additive (A), which is a dispersant, particularly a phosphorus-containing compound. The dispersion contains an additive (B), and the main components of additives (A and B) are the same (i.e., the components contained in the additive in the largest quantity by weight). Development is performed using the first developing solution, followed by development using the second developing solution. In this case, the development and removal efficiency of metal particles and / or metal oxide particles adhering to the substrate is particularly good.

[0146] In one embodiment, copper oxide is preferably more soluble in the second developer than in the first developer. Such a developer is particularly advantageous in improving the development and removal efficiency when metal oxide particles contain copper oxide.

[0147] The solubility of metal particles and / or metal oxide particles in the first developing solution, or the solubility of copper oxide in the first developing solution, is preferably 0.1 mg / L or more, or 1.0 mg / L or more, or 10 mg / L or more, or 100 mg / L or more, preferably 10000 mg / L or less, or 5000 mg / L or less, or 1000 mg / L or less, or 500 mg / L or less. In particular, when the metal particles and / or metal oxide particles include copper oxide particles, by setting the solubility of copper oxide in the first developing solution to 0.1 mg / L or more, the high solubility of copper oxide particles results in high developing effect. Furthermore, by setting this solubility to 5000 mg / L or less, damage to the metal wiring can be reduced.

[0148] The solubility of metal particles and / or metal oxide particles in the second developer, or the solubility of copper oxide in the second developer, is preferably 0.1 mg / L or more, or 1.0 mg / L or more, or 10 mg / L or more, or 100 mg / L or more, preferably less than 10,000 mg / L, or less than 5,000 mg / L, or less than 1,000 mg / L.

[0149] (Surface free energy)

[0150] The surface free energy of the first developer, the second developer, and the additional developer is preferably 10 mN / m or more, or 15 mN / m or more, or 20 mN / m or more, and more preferably 75 mN / m or less, or 60 mN / m or less, or 50 mN / m or less. In this invention, the surface free energy is a value measured by the suspended drop method using a contact angle meter.

[0151] From the viewpoint of improving the development and removal effect by ensuring good affinity between the developer and the dried coating, the difference between the surface free energy of the first developer, the second developer, and the additional developer and the surface free energy of the dispersion is preferably 50 mN / m or less, or 25 mN / m or less, or 10 mN / m or less. The most preferred difference is 0 mN / m, but from the viewpoint of ease of manufacturing the developer and the dispersion, it can be, for example, 1 mN / m or more, or 5 mN / m or more.

[0152] [Composition of the dispersion and the dried coating]

[0153] In one embodiment, the dried coating film comprising metal particles and / or metal oxide particles of the present invention is formed by coating a dispersion comprising metal particles and / or metal oxide particles, a dispersion medium, and any additive (B) (in one embodiment, a dispersant and / or a reducing agent) onto a substrate, followed by drying. Therefore, in one embodiment, the mass ratio of components other than the dispersion medium in the dried coating film can be considered to be the same as the mass ratio of components other than the dispersion medium in the dispersion medium. Alternatively, the content of metal elements in the dried coating film can be confirmed using SEM (scanning electron microscopy) and EDX (energy dispersive X-ray diffraction) devices.

[0154] The content of additive (B) (or dispersant in one method) in the dispersion and the dried coating film can be confirmed using a TG-DTA (thermogravimetric differential thermal analysis) apparatus.

[0155] The content of reducing agent in the dispersion can be confirmed using the Salomon method with a GC / MS (gas chromatography / mass spectrometry) apparatus. Furthermore, the content of reducing agent in the dried coating film can be confirmed using the Salomon method with a GC / MS apparatus after redispersing the dried coating film in the dispersion medium.

[0156] The following are measurement examples using hydrazine as a reducing agent.

[0157] (Hydrazine quantification method)

[0158] Add 33 μg hydrazine and 33 μg salomonide (hydrazine) to a 50 μL dispersion. 15 (N2H4), 1 ml benzaldehyde 1% acetonitrile solution. Finally, add 20 μL phosphoric acid, and after 4 hours, perform GC / MS measurement.

[0159] Similarly, 66 μg of hydrazine and 33 μg of salomon (hydrazine) were added to a 50 μL dispersion. 15 (N2H4), 1 ml benzaldehyde 1% acetonitrile solution. Finally, add 20 μL phosphoric acid, and after 4 hours, perform GC / MS measurement.

[0160] Similarly, 133 μg of hydrazine and 33 μg of salomon (hydrazine) were added to a 50 μL dispersion. 15 (N2H4), 1 ml benzaldehyde 1% acetonitrile solution. Finally, add 20 μL phosphoric acid, and after 4 hours, perform GC / MS measurement.

[0161] Finally, without adding hydrazine, 33 μg of salomonin (hydrazine) was added to a 50 μL dispersion. 15 The mixture was prepared by adding N2H4, 1 ml of benzaldehyde in 1% acetonitrile solution, and finally 20 μL of phosphoric acid. After 4 hours, GC / MS measurements were performed.

[0162] Based on the GC / MS measurements at the above four points, the peak area of ​​hydrazine was obtained from the chromatogram at m / z = 207. Next, the peak area of ​​Salomon was obtained from the mass chromatogram at m / z = 209. The x-axis was calculated as the weight of added hydrazine divided by the weight of added Salomon, and the y-axis was calculated as the peak area of ​​hydrazine divided by the peak area of ​​Salomon, thus obtaining the calibration curve using the Salomon method.

[0163] The weight of hydrazine is obtained by dividing the value of the Y intercept obtained from the calibration curve by the weight of the added hydrazine / the weight of the added salomon.

[0164] (i) Metal particles and / or metal oxide particles)

[0165] The metal particles and / or metal oxide particles contain metals such as aluminum, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, ruthenium, rhodium, palladium, silver, indium, tin, antimony, iridium, platinum, gold, thallium, lead, bismuth, etc., and can be one of these, an alloy containing two or more of these, or a mixture containing two or more of these. Furthermore, oxides of the metals exemplified above can be used as metal oxides. Silver or copper metal oxide particles are preferred because they are easily reduced when irradiated with a laser, forming uniform metal wiring. In particular, copper metal oxide particles have high stability in air, allowing them to be obtained at low cost, which is advantageous from an operational point of view. Copper oxide includes, for example, cuprous oxide (Cu₂O) and copper oxide (CuO). Cuprous oxide is particularly preferred from the viewpoints of high laser absorption, low-temperature sintering capability, and the ability to form sintered products with low resistance. Cuprous oxide and the second copper oxide can be used alone or in combination.

[0166] In one embodiment, the metal oxide particles comprise or are copper oxide particles. The copper oxide particles may have a core / shell structure, and either the core or the shell may comprise cuprous oxide and / or a second copper oxide.

[0167] There is no particular limitation on the average secondary particle size of the copper oxide particles, but it is preferably less than 500 nm, or less than 200 nm, or less than 100 nm, or less than 80 nm, or less than 50 nm, or less than 20 nm. The average secondary particle size is preferably more than 1 nm, or more than 5 nm, or more than 10 nm, or more than 15 nm.

[0168] The average secondary particle size refers to the average particle size of an aggregate (secondary particle) formed by multiple primary particles. A secondary particle size of 500 nm or less is preferred because it tends to easily form fine metallic wirings on the support. A secondary particle size of 1 nm or more, particularly 5 nm or more, improves the long-term storage stability of the dispersion. This average secondary particle size is measured using a dynamic scattering method.

[0169] The average primary particle size of the primary particles constituting the secondary particles is preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 20 nm or less. The average primary particle size is preferably 1 nm or more, more preferably 2 nm or more, and even more preferably 5 nm or more.

[0170] When the average primary particle size is below 100 nm, there is a tendency to lower the firing temperature, which will be discussed later. The reason for this low-temperature firing can be attributed to the fact that the smaller the particle size, the greater its surface energy and the lower its melting point.

[0171] Furthermore, a primary particle size of 1 nm or more is preferred as it provides good dispersibility. When a wiring pattern is formed on a substrate, from the viewpoint of good adhesion to the substrate and low resistivity, a particle size of 2 nm or more, or 5 nm or more, and more preferably 100 nm or less, or 50 nm or less, is preferred. This tendency becomes significant when the substrate is resin. The average primary particle size is measured based on an image observed using a transmission electron microscope. The diameter of a single particle ((major diameter + minor diameter) / 2) is measured based on the image, and the average value of 10 measured particles is taken as the primary particle size.

[0172] The dispersion and the dried coating film may contain copper particles. That is, the dispersion and the dried coating film of the present invention may contain copper.

[0173] The dispersion and the dried coating may contain copper oxide particles and copper particles. In this case, from the viewpoint of electrical conductivity and crack prevention, the mass ratio of copper particles to copper oxide particles (hereinafter referred to as "copper particles / copper oxide particles") is preferably 1.0 or more, or 1.5 or more, or 2.0 or more, preferably 7.0 or less, or 6.0 or less, or 5.0 or less.

[0174] Regarding the content of metal particles and / or metal oxide particles in the dispersion, the total content of metal particles and metal oxide particles, relative to 100% by mass of the dispersion, is preferably 0.50% by mass or more, or 1.0% by mass or more, or 5.0% by mass or more, preferably 60% by mass or less, or 50% by mass or less. When the total content is 60% by mass or less, there is a tendency to easily suppress the aggregation of metal particles and / or metal oxide particles. When the total content is 0.50% by mass or more, the metal wiring (i.e., conductive film) obtained by firing the dried coating film by laser irradiation will not become too thin and tends to have good conductivity.

[0175] Regarding the content of metal particles and / or metal oxide particles in the dried coating film, the total content of metal particles and metal oxide particles, relative to 100% by mass of the dried coating film, is preferably 40% by mass or more, more preferably 55% by mass or more, and even more preferably 70% by mass or more. Furthermore, this content is preferably 98% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less.

[0176] Furthermore, regarding the content of metal particles and / or metal oxide particles in the dried coating film, the total content of metal particles and metal oxide particles, relative to 100% by volume of the dried coating film, is preferably 10% by volume or more, more preferably 15% by volume or more, and even more preferably 25% by volume or more. Additionally, this content is preferably 90% by volume or less, more preferably 76% by volume or less, and even more preferably 60% by volume or less.

[0177] If the content of metal particles and / or metal oxide particles in the dried coating is 40% by mass or more or 10% by volume or more, good electrical conductivity is exhibited by melting and bonding the particles together through firing, which is therefore preferred. Higher concentrations of metal particles and / or metal oxide particles result in better conductivity, but when the content is 98% by mass or 90% by volume or less, the dried coating adheres well to the substrate to a degree capable of stably forming metal wiring, especially when it is 95% by mass or 76% by volume or less, the adhesion to the substrate is even stronger, which is therefore preferred. Furthermore, when the content is 90% by mass or 60% by volume or less, the dried coating has high flexibility, is less prone to cracking during bending, and has improved reliability.

[0178] ((ii) Additive (B))

[0179] In one embodiment, the dispersion and the dried coating film contain an additive (B). Examples of additives (B) include surfactants, dispersants, reducing agents, complexing agents, etc. Dispersants help to disperse metal particles and / or metal oxide particles well.

[0180] Preferred examples of the surfactant as additive (B) are the same as those exemplified with respect to additive (A). From the viewpoint of achieving good dispersion of metal particles and / or metal oxide particles, the content of surfactant in the dispersion is preferably 0.1% by mass or more, or 0.2% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more. From the viewpoint of ensuring that the residue from the surfactant in the conductive film obtained by firing does not increase and that the conductivity is good, it is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less, or 8.0% by mass or less.

[0181] The number average molecular weight of the dispersant used as additive (B) is not particularly limited, but is preferably 300 to 300,000, more preferably 300 to 30,000, and even more preferably 300 to 10,000. If the number average molecular weight is 300 or higher, there is a tendency for the dispersion stability of the dispersion to increase. In addition, if it is 300,000 or lower, it is easier to fire during wiring formation. If it is 30,000 or lower, the amount of dispersant residue after firing is less, which can reduce the resistance of the metal wiring.

[0182] As additive (B), particularly a dispersant, a phosphorus-containing organic compound is preferred from the viewpoint of excellent dispersibility of metal particles and / or metal oxide particles. Furthermore, as additive (B), particularly a dispersant, from the viewpoint of adsorbing onto metal particles and / or metal oxide particles and suppressing particle aggregation through steric hindrance, a group (e.g., hydroxyl group) with affinity for these particles is preferred. It is particularly preferred to use metal oxide particles and a hydroxyl-containing dispersant together. Additive (B), particularly a dispersant, preferably contains a phosphorus-containing organic compound. A particularly preferred example of additive (B), particularly a dispersant, is a phosphorus-containing organic compound having a phosphate group.

[0183] Phosphorus-containing organic compounds are preferably easily decomposed or evaporated by light and / or heat. By using organic materials that are easily decomposed or evaporated by light and / or heat, it is less likely that organic residue will remain after firing, resulting in metal wiring with low resistivity.

[0184] The decomposition temperature of phosphorus-containing organic compounds is not limited, but is preferably below 600°C, more preferably below 400°C, and even more preferably below 200°C. From the viewpoint of the stability of phosphorus-containing organic compounds, the decomposition temperature can preferably be above 60°C, above 90°C, or above 120°C.

[0185] The boiling point of phosphorus-containing organic compounds under normal pressure is not limited, but is preferably below 300°C, more preferably below 200°C, and even more preferably below 150°C. From the viewpoint of the stability of phosphorus-containing organic compounds, the boiling point can preferably be above 60°C, above 90°C, or above 120°C.

[0186] The absorption characteristics of phosphorus-containing organic compounds are not limited, but those capable of absorbing the laser light used in the firing process are preferred. It should be noted that, in this invention, the ability to absorb the laser light used in the firing process refers to an absorption coefficient of 0.10 cm⁻¹ at a wavelength of 532 nm, measured using a UV-Vis spectrophotometer. -1 That's all. More specifically, it is preferable to absorb light with a light emission wavelength (center wavelength) of, for example, 355 nm, 405 nm, 445 nm, 450 nm, 532 nm, 1064 nm, etc. (i.e., an absorption coefficient of 0.10 cm⁻¹ at that wavelength) that is the center wavelength of the laser used in firing. -1 Phosphorus-containing organic compounds (as described above). In particular, when the substrate is a resin substrate, phosphorus-containing organic compounds that absorb light with a center wavelength of 355 nm, 405 nm, 445 nm and / or 450 nm are preferred.

[0187] From the viewpoint of improving the stability of the dispersion in the atmosphere, phosphorus-containing organic compounds are preferred as phosphate esters. For example, based on the following general formula (1):

[0188] [Chemical Formula 4]

[0189]

[0190] (In the formula, R is a monovalent organic group.)

[0191] The phosphate monoester shown exhibits excellent adsorption of metal oxide particles and moderate adhesion to the substrate, thus contributing to both stable formation of metal wiring and good development of unexposed areas, which is preferable. Examples of R include substituted or unsubstituted hydrocarbon groups.

[0192] As an example of a phosphate monoester, a compound having a structure represented by the following formula (2) can be illustrated:

[0193] [Chemical Formula 5]

[0194]

[0195] In addition, as an example of a phosphate monoester, a compound having a structure represented by the following formula (3) can also be illustrated:

[0196] [Chemical Formula 6]

[0197]

[0198] (In the formula, l, m, and n are each an independent integer from 1 to 20.)

[0199] In the above formula (3), l is an integer from 1 to 20, preferably an integer from 1 to 15, more preferably an integer from 1 to 10, m is an integer from 1 to 20, preferably an integer from 1 to 15, more preferably an integer from 1 to 10, and n is an integer from 1 to 20, preferably an integer from 1 to 15, more preferably an integer from 1 to 10.

[0200] The organic structure of phosphorus-containing organic compounds can be derived from polyethylene glycol (PEG), polypropylene glycol (PPG), polyimide, polyester (e.g., polyethylene terephthalate (PET), polyethylene naphthalate (PEN)), polyethersulfone (PES), polycarbonate (PC), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polyacetal, polyaryl ester (PAR), polyamide (PA), polyamide-imide (PAI), polyether-imide (PEI), polyphenylene ether (PPE), polyphenylene sulfide (PPS), polyetherketone (PEK), polyphthalamide (PPA), polyether nitrile (PENt), polybenzimidazole (PBI), polycarbodiimide, polysiloxane, polymethacrylamide, nitrile rubber, acrylic rubber, polytetrafluoroethylene, epoxy resin, etc. The structures of compounds such as phenolic resin, melamine resin, urea resin, polymethyl methacrylate resin (PMMA), polybutene, polypentene, ethylene-propylene copolymer, ethylene-butene-diene copolymer, polybutadiene, polyisoprene, ethylene-propylene-diene copolymer, butyl rubber, polymethylpentene (PMP), polystyrene (PS), styrene-butadiene copolymer, polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polyether ether ketone (PEEK), phenolic varnish, benzocyclobutene, polyvinylphenol, polychloroprene, polyoxymethylene, polysulfone (PSF), polysulfide, silicone resin, aldose, cellulose, linear starch, pullulan, dextrin, dextran, fructan, chitin, etc. (specifically, structures modified by functional groups, functional group modification, or polymerization). Phosphorus-containing organic compounds with a polymer backbone selected from polyethylene glycol, polypropylene glycol, polyacetal, polybutene, and polysulfides are easily decomposed and do not leave residues in the metal wiring obtained after firing, and are therefore preferred.

[0201] As a specific example of phosphorus-containing organic compounds, commercially available materials can be used; specifically, BYK-Chemie can be cited. DISPERBYK (registered trademark)-102, DISPERBYK-103, DISPERBYK-106, DISPERBYK-109, DISPERBYK-110, DISPERBYK-111, DISPERBYK-118, DISPERBYK-140, DISPERBYK-145, DISPERBYK-168, DISPERBYK -180, DISPERBYK-182, DISPERBYK-187, DISPERBYK-190, DISPERBYK-191, DISPERBYK-193, DISPERBYK-194N, DISPERBYK-199, DISPERBYK-2000, DISPERBYK-2001, DISPERBYK-2008, DISPERBYK D ISPERBYK-2061, DISPERBYK-2164, DISPERBYK-2096, DISPERBYK-2200, BYK (registered trademark)-405, BYK-607, BYK-9076, BYK-9077, BYK-P105, and PLYSURF (registered trademark) M208F and PLYSURFDBS manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd. These materials can be used alone or in combination.

[0202] When the total volume of metal particles and metal oxide particles in the dispersion and the dried coating is set to 100 parts by volume, the content of additive (B), particularly the dispersant, can be 5 parts by volume or more and 900 parts by volume or less. The lower limit is preferably 10 parts by volume or more, more preferably 30 parts by volume or more, and even more preferably 60 parts by volume or more. The upper limit is preferably 480 parts by volume or less, more preferably 240 parts by volume or less.

[0203] When converted to parts by mass, the content of additive (B), particularly dispersant, is preferably 1 part by mass or more and 150 parts by mass or less relative to a total of 100 parts by mass of metal particles and metal oxide particles. The lower limit is preferably 2 parts by mass or more, more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more. The upper limit is preferably 80 parts by mass or less, more preferably 40 parts by mass or less. If the above-mentioned content of additive (B) is 5 parts by volume or more or 1 part by mass or more, a film with a thickness of submicron can be easily formed. In addition, if the above-mentioned content of additive (B) is 10 parts by volume or more or 5 parts by mass or more, a thick film with a thickness of, for example, tens of μm can be easily formed. If the above-mentioned content of additive (B) is 30 parts by volume or more or 10 parts by mass or more, a highly flexible dry coating film that is not prone to cracking even when bent can be obtained. In addition, if the above-mentioned content of additive (B) is 900 parts by volume or less or 150 parts by mass or less, good metal wiring can be obtained by firing.

[0204] The content of additive (B) in the dispersion is preferably 0.10% by mass or more, or 0.20% by mass or more, or 0.50% by mass or more, or 1.0% by mass or more, and preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less, or 8.0% by mass or less. When the content is 20% by mass or less, the residue from additive (B) in the conductive film obtained by firing does not increase, and it tends to have good conductivity. In addition, when the content is 0.10% by mass or more, the metal particles and / or metal oxide particles do not agglomerate, and good dispersibility can be obtained.

[0205] The reducing agent, as additive (B), remains in the dispersion due to its use during the synthesis of metal particles and / or metal oxide particles, and therefore may also remain in the dried coating film. The reducing agent preferably contains hydrazine and / or hydrazine hydrate, more preferably hydrazine and / or hydrazine hydrate. When the dispersion contains metal oxide particles and the dried coating film contains the reducing agent, the metal oxide (e.g., copper oxide) is readily reduced to a metal (e.g., copper) when the dried coating film is irradiated with a laser, and the reduced metal (e.g., copper) can be made to have low resistivity. The reducing agent remains in the unexposed portions (i.e., areas not irradiated with laser) of the dried coating film.

[0206] From the viewpoint of achieving a good reduction effect, the mass ratio of the content of reducing agent in the dispersion and the dried coating to the total content of metal particles and metal oxide particles is preferably 0.0001 or more, or 0.0010 or more, or 0.0020 or more, or 0.0040 or more. From the viewpoint of avoiding excessive reducing agent residue and obtaining low-resistance metal wiring, it is preferably 0.10 or less, or 0.050 or less, or 0.030 or less.

[0207] In addition, the total content of hydrazine and hydrazine hydrate (hydrazine content basis) in the dispersion and the dried coating preferably satisfies the following relationship with the content of copper oxide.

[0208] 0.0001 ≤ (mass of hydrazine / mass of copper oxide) ≤ 0.10

[0209] Preferred examples of the complexing agent as additive (B) are the same as those exemplified with respect to additive (A). From the viewpoint of achieving good dispersion of metal particles and / or metal oxide particles, the content of the complexing agent in the dispersion is preferably 0.1% by mass or more, or 0.2% by mass or more, or 0.5% by mass or more, or 1.0% by mass or more. From the viewpoint of ensuring that the residue of the complexing agent in the conductive film obtained by firing does not increase and that the conductivity is good, it is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less, or 8.0% by mass or less.

[0210] (iii) Dispersion medium)

[0211] To disperse metal particles and / or metal oxide particles, a dispersion medium may be contained in the dispersion, and in one manner, it may be contained in the dried coating.

[0212] Specific examples of dispersion media include alcohols (monohydric alcohols and polyhydric alcohols (e.g., diols)), ethers of alcohols (e.g., diols), esters of alcohols (e.g., diols), etc. More specific examples include propylene glycol monomethyl ether acetate, 3-methoxy-3-methylbutyl acetate, ethoxyethyl propionate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, ethylene glycol butyl ether, ethylene glycol ethyl ether, ethylene glycol methyl ether, xylene, mesitylene, ethylbenzene, octane, nonane, decane, ethylene glycol, 1,2-propanediol, 1,3-butanediol, 2-pentanediol, 2-methylpentane-2,4-diol, 2,5-hexanediol, 2,4-heptanediol, 2-ethylhexane-1,3-diol, diethylene glycol, dipropylene glycol, hexanediol, octanediol, triethylene glycol, tri-1,2-propanediol Alcohols, ethyl glycerol, n-propyl acetate, isopropyl acetate, pentane, hexane, cyclohexane, methylcyclohexane, toluene, methyl ethyl ketone, methyl isobutyl ketone, dimethyl carbonate, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, 2-methylbutanol, sec-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonanol, 2,6-dimethyl-4-heptanol, n-decanol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol, etc.

[0213] From the viewpoint of dispersibility of metal particles and / or metal oxide particles, monohydric or polyhydric alcohols with 10 or fewer carbon atoms are more preferred. Among monohydric alcohols with 10 or fewer carbon atoms, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, and tert-butanol are even more preferred. These alcohols can be used alone or in combination.

[0214] The solid content of the dispersion is preferably 0.6% by mass or more, or 1.2% by mass or more, or 6.0% by mass or more, preferably 80% by mass or less, or 75% by mass or less, or 58% by mass or less. The solid content of the dispersion can be determined by measuring 0.5 to 1.0 g of the dispersion, heating it in air at 60°C for 4.5 hours, and dividing the weight after heating by the weight before heating. In one embodiment, the solid content of the dispersion corresponds to the content of metal particles and / or metal oxide particles in the dispersion. When the solid content is 0.6% by mass or more and 80% by mass or less, the dispersion can have a viscosity suitable for coating onto a substrate.

[0215] The viscosity of the dispersion is preferably 0.1 mPa·s or higher, or 1 mPa·s or higher, more preferably 100,000 mPa·s or lower, or 10,000 mPa·s or lower, or 1,000 mPa·s or lower. When the viscosity is 0.1 mPa·s or higher and 100,000 mPa·s or lower, the dispersion can be coated more uniformly onto the substrate. In this invention, the viscosity is measured using an E-type viscometer.

[0216] From the viewpoint of preventing the dissolution of metal particles and / or metal oxide particles in the dispersion, the pH of the dispersion is preferably 4.0 or higher, or 5.0 or higher, or 6.0 or higher. From the viewpoint of reducing damage to the substrate, the pH may, for example, be 10.0 or lower, or 9.0 or lower, or 8.0 or lower.

[0217] From the perspective of being able to uniformly coat the dispersion onto the substrate without any unevenness, the surface free energy of the dispersion is preferably 10 mN / m or more, or 12 mN / m or more, or 15 mN / m or more, preferably 50 mN / m or less, or 35 mN / m or less, or 25 mN / m or less.

[0218] From the viewpoint of easily manufacturing metal wiring with low resistance and excellent mechanical properties, the thickness of the dried coating is preferably 0.1 μm or more, or 0.5 μm or more, or 1.0 μm or more. From the viewpoint of manufacturing fine-sized metal wiring with high precision, it is preferably 50 μm or less, or 25 μm or less, or 10 μm or less.

[0219] [Substrate]

[0220] The substrate forms the surface on which the metal wiring is arranged. To ensure electrical insulation between the metal wirings formed by laser, the substrate is preferably made of an insulating material. However, it is not necessary for the entire substrate to be an insulating material. It is sufficient that the portion forming the surface on which the metal wiring is arranged is an insulating material.

[0221] Furthermore, to prevent the substrate from being burned by the laser and generating smoke during laser irradiation, the substrate material is preferably a material with a heat resistance temperature of 60°C or higher. The substrate does not need to be composed of a single raw material; to improve the heat resistance temperature, for example, glass fibers can be added to the resin.

[0222] The surface of the substrate for drying the coating can be flat or curved, and can also be a surface containing differences in height, etc. More specifically, the substrate can be a substrate (e.g., a plate, a film, or a sheet) or a three-dimensional object (e.g., a housing). A plate is, for example, a support used in circuit boards such as printed circuit boards. A film or sheet is, for example, a base film used as a thin-film insulator for flexible printed circuit boards.

[0223] Examples of three-dimensional objects include the housings of electrical devices such as mobile phone terminals, smartphones, smart glasses, televisions, and personal computers. Other examples of three-dimensional objects in the automotive industry include the front bulkhead, dashboard, steering wheel, and chassis.

[0224] Specific examples of substrates include substrates made of inorganic materials (hereinafter referred to as "inorganic substrates") or substrates made of resins (hereinafter referred to as "resin substrates").

[0225] Inorganic substrates can be made of materials such as glass, silicon, mica, sapphire, crystal, clay films, and ceramics. Ceramic materials can be selected from materials such as alumina, silicon nitride, silicon carbide, zirconium oxide, yttrium oxide, and aluminum nitride, as well as mixtures of at least two of these. Alternatively, substrates with particularly high light transmittance, such as those made of glass, sapphire, or crystal, can be used as inorganic substrates.

[0226] As resin base materials, materials such as polypropylene (PP), polyimide (PI), polyester (polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), etc.), polyethersulfone (PES), polycarbonate (PC), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polyacetal (POM), polyarylate (PAR), polyamide (PA) (PA6, PA66, etc.), polyamide-imide (PAI), polyetherimide (PEI), polyphenylene ether (PPE), modified polyphenylene ether (m-PPE), polyphenylene sulfide (PPS), polyetherketone (PEK), polyetheretherketone (PEEK), polyphthalamide (PPA), polyether nitrile (PENt), polybenzimidazole (PBI), polycarbodiimide, polymethacrylamide, nitrile rubber, acrylic rubber, and polytetrafluoroethylene (PTFE) can be used. Supports composed of fluoroethylene, epoxy resin, phenolic resin, melamine resin, urea resin, polymethyl methacrylate resin (PMMA), polybutene, polypentene, ethylene-propylene copolymer, ethylene-butene-diene copolymer, polybutadiene, polyisoprene, ethylene-propylene-diene copolymer, butyl rubber, polymethylpentene (PMP), polystyrene (PS), styrene-butadiene copolymer, polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), phenolic varnish, benzocyclobutene, polyethylene phenol, polychloroprene, polyoxymethylene, polysulfone (PPSU), polyphenylsulfone resin (COP), cyclic olefin polymer (COP), acrylonitrile-butadiene-styrene resin (ABS), acrylonitrile-styrene resin (AS), polytetrafluoroethylene resin (PTFE), polychlorotrifluoroethylene resin (PCTFE), and silicone resin, etc.

[0227] In addition to the above, resin sheets containing cellulose nanofibers can also be used as substrates, for example.

[0228] In particular, substrates selected from at least one of the group consisting of PI, PET and PEN have excellent adhesion to metal wiring, good market liquidity, and can be obtained at low cost, which makes sense from an operational point of view and is preferred.

[0229] Furthermore, substrates selected from at least one of the group consisting of PP, PA, ABS, PE, PC, POM, PBT, m-PPE, and PPS, especially when used for housings, exhibit excellent adhesion to metal wiring, as well as excellent formability and mechanical strength after molding. Moreover, they possess sufficient heat resistance to withstand heat generated by laser irradiation or similar processes during the formation of metal wiring, and are therefore preferred.

[0230] Furthermore, the material used for the three-dimensional object is preferably selected from at least one of the group consisting of polypropylene resin, polyamide resin, acrylonitrile butadiene styrene resin, polyethylene resin, polycarbonate resin, polyacetal resin, polybutylene terephthalate resin, modified polyphenylene ether resin, and polyphenylene sulfide resin.

[0231] The flexural temperature of the resin substrate is preferably below 400°C, more preferably below 280°C, and even more preferably below 250°C. A substrate with a flexural temperature below 400°C is readily available at low cost, which is excellent from an operational point of view and is therefore preferred. From the viewpoint of the processability of the resin substrate, the flexural temperature is preferably above 70°C, or above 80°C, or above 90°C, or above 100°C. The flexural temperature of the present invention is a value obtained according to JIS K7191.

[0232] When the substrate is, for example, a plate, film, or sheet, its thickness is preferably 1 μm or more, or 25 μm or more, and more preferably 100 mm or less, or 10 mm or less, or 250 μm or less. When the substrate thickness is 250 μm or less, the manufactured electronic device can be made lighter, more space-saving, and more flexible, and is therefore preferred.

[0233] It should be noted that when the substrate is a three-dimensional object, from the viewpoint of well exhibiting the mechanical strength and heat resistance of the substrate, its maximum dimension (i.e., the maximum length of one side) is preferably 1 μm or more, or 200 μm or more, preferably 1000 mm or less, or 100 mm or less, or 5 mm or less.

[0234] [Arithmetic mean surface roughness Ra of the substrate]

[0235] As a substrate on which metal wiring is disposed, examples include substrates made of inorganic materials (hereinafter referred to as "inorganic substrates") or substrates made of resin (hereinafter referred to as "resin substrates"). In one embodiment, the substrate has a surface with a surface roughness controlled within a specific range. In one embodiment, the arithmetic mean surface roughness Ra of the surface is 70 nm or more and 10,000 nm or less, preferably 100 nm or more or 150 nm or more, and preferably 5,000 nm or less or 1,000 nm or less.

[0236] In this invention, the arithmetic mean surface roughness Ra, as described in one of the [Examples] sections, is a value measured using a stylus-type surface shape measuring instrument. It should be noted that the surface roughness of a substrate with a coating can be measured using the following method: The substrate with the coating is immersed in 0.6% by mass of nitric acid or hydrochloric acid, the total amount of which the substrate is immersed, and agitated at 60 rpm for at least 12 hours to dissolve the coating. After the coating is completely dissolved, the substrate is rinsed with at least 50 ml of ultrapure water, and then measured using a stylus-type surface shape measuring instrument as described in the [Examples] section.

[0237] If the arithmetic mean surface roughness Ra is 70 nm or more, the dispersion enters the recesses of the uneven surface of the substrate through an anchoring effect. Therefore, the dried coating adheres well to the substrate, forming metal wiring that is difficult to peel off even during development. This results in less damage to the metal wiring during development and less increase in resistance after development. Furthermore, if the arithmetic mean surface roughness Ra is 10000 nm or less, the unevenness of the substrate surface is not excessive, allowing for the formation of a coating with a uniform thickness on the surface. This results in metal wiring that is less prone to breakage and exhibits minimal variation in resistance values ​​between areas. Additionally, an arithmetic mean surface roughness Ra of 10000 nm or less is also advantageous in terms of good developability and removal properties in unexposed areas.

[0238] [The various steps in the manufacturing process of metal wiring]

[0239] The following is for reference Figures 1-7 The following describes the examples of each step in the manufacturing method of the metal wiring according to this embodiment.

[0240] (Preparation of dispersions)

[0241] In one approach, the dispersion is manufactured prior to the coating process. The following explanation uses the manufacture of a dispersion containing cuprous oxide particles as an example.

[0242] Cuprous oxide particles can be synthesized, for example, by the methods described below.

[0243] (1) A method of adding water and acetylacetone copper complex (hereinafter referred to as organocopper compound) to a polyol solvent, temporarily heating the organocopper compound to dissolve it, further adding the amount of water required for the reaction, and heating to the reduction temperature of the organocopper for reduction.

[0244] (2) A method of heating an organocopper compound (copper-N-nitrosophenylhydroxylamine complex) in an inert atmosphere at a high temperature of about 300°C in the presence of a protective agent such as hexadecylamine.

[0245] (3) A method of reducing copper salt dissolved in a solvent (e.g., water) with a reducing agent (e.g., hydrazine).

[0246] Of the methods (1) to (3) above, method (3) is the most convenient to operate and can produce particles with small particle size, therefore it is preferred.

[0247] The method of the above (1) can be used, for example, in the Anocontech Co., Ltd. It was conducted under the conditions described in ル・リング・リング, No. 40, Vol. 2, p. 359, 2001.

[0248] The method (2) described above can be performed, for example, under the conditions described in Science & Technology, 1999, Vol. 121, p. 11595.

[0249] Reference Figure 1 and Figure 6 In the method described above (3), solvent A, copper salt B, and reducing agent C are supplied to a container, and copper salt B is reduced by reducing agent C, thereby obtaining copper oxide particles. Figure 1 (a)). As a copper salt, a divalent copper salt is preferred, and examples include copper(II) acetate, copper(II) nitrate, copper(II) carbonate, copper(II) chloride, and copper(II) sulfate. As for the amount of hydrazine used, it is preferably 0.2 moles or more or 0.25 moles or more relative to 1 mole of copper salt, and more preferably 2 moles or less or 1.5 moles or less.

[0250] Solvent A can contain water and water-soluble organic compounds. By adding a water-soluble organic compound to the aqueous solution formed by dissolving the copper salt, the melting point of the aqueous solution decreases, thus enabling reduction at lower temperatures. Examples of water-soluble organic compounds that can be used include alcohols and water-soluble polymers.

[0251] Examples of alcohols that can be used include methanol, ethanol, 1-propanol, 1-butanol, 1-hexanol, 1-octanol, 1-decanol, ethylene glycol, propylene glycol, and glycerol. Examples of water-soluble polymers that can be used include polyethylene glycol, polypropylene glycol, and polyethylene glycol-polypropylene glycol copolymers.

[0252] The reduction temperature in the method described above (3) can be set to, for example, -20°C to 60°C, preferably -10°C to 30°C. This reduction temperature can be kept constant during the reaction, or it can be increased or decreased midway. For the initial stage of the reaction where hydrazine has high reactivity, reduction is preferably carried out below 10°C, more preferably below 0°C. The reduction time is preferably 30 minutes to 300 minutes, more preferably 90 minutes to 200 minutes. The atmosphere during reduction is preferably an inert atmosphere such as nitrogen or argon.

[0253] Next, by centrifugation of the reaction solution (step S101), supernatant 2a and precipitate 2b are obtained. Figure 1 (b)). By recovering precipitate 2b (step S102), copper oxide particles as precipitate 2b are obtained.

[0254] On the other hand, commercially available products can be used as copper oxide particles. For example, cuprous oxide particles with an average primary particle size of 18 nm sold by EM Japan can be cited as examples of commercially available products.

[0255] Next, dispersion medium D and additive (B) E (or dispersant) are added to precipitate 2b, and the mixture is stirred, for example by a known method such as a homogenizer, to disperse the copper oxide particles in the dispersion medium. Figure 1 (c) It should be noted that, depending on the dispersion medium, copper oxide particles may sometimes be difficult to disperse or insufficiently dispersed. In such cases, it is preferable to use, for example, an alcohol, such as butanol, which is easy to disperse copper oxide particles, to disperse the copper oxide, and then perform solvent replacement to the desired dispersion medium and / or concentration to the desired concentration (step S103). As an example, methods of concentration using an ultrafiltration (UF) membrane and methods of repeated dilution and concentration using the desired dispersion medium can be cited.

[0256] For example, through the steps described above, the target dispersion can be obtained as the unused dispersion 2c ( Figure 1 (d)

[0257] (Grinding of the substrate)

[0258] In one embodiment, substrate 1 ( Figure 1 The dispersion coating surface of (e) has a controlled (specifically, within the scope of the invention) arithmetic mean surface roughness. A typical manner of the method of the invention may include grinding the surface of the substrate 1 (step S201) prior to the coating process, thereby allowing the substrate 1 to have a ground surface S( Figure 1 (f)). Grinding is advantageous in that it allows for easy control of the arithmetic mean surface roughness of the substrate surface. In this invention, grinding includes both smoothing and roughening. There are no particular limitations on the grinding method; examples include physical grinding methods using grinding stones (rotary grinding stones, etc.), sandpaper, abrasive paper, abrasive compounds, etc., and chemical grinding methods using electrolytic grinding, solvent impregnation, etc. An appropriate grinding method can be selected based on the material and surface morphology of the substrate surface to be ground, and the desired arithmetic mean surface roughness value.

[0259] (Coating process)

[0260] In this process, the dispersion of the present invention (which may be unused dispersion 2c and / or regenerated dispersion 3c described later) is coated on the surface of the substrate 1, where the arithmetic mean surface roughness can be controlled (step S11), to form dispersion layer 2d. Figure 1 (g) The method for forming the dispersion layer is not particularly limited, and coating methods such as mold coating, spin coating, slit coating, rod coating, doctor blade coating, spraying, and dip coating can be used. It is preferred to use these methods to coat the dispersion on the substrate with a uniform thickness.

[0261] (Drying process)

[0262] In this process, the substrate 1 and the dispersion layer 2d formed on the substrate are dried (step S12) to form a structure 10 with a dried coating film having the substrate 1 and a dried coating film 2e disposed on the substrate 1. Figure 1 (h)). The drying conditions can be adjusted to control the solid content of the dried coating within a desired range (in one manner, the ranges listed in this invention).

[0263] From the viewpoint of shortening drying time and improving industrial productivity, the drying temperature is preferably 40°C or higher, or 50°C or higher, or 60°C or higher. From the viewpoint of suppressing deformation of the substrate (especially resin substrate), the drying temperature is preferably 120°C or lower, or 110°C or lower, or 100°C or lower, or 90°C or lower. From the viewpoint of preventing excessive volatilization of the dispersion medium in the dispersion layer, controlling the solid content of the dried coating film to a desired level, thereby facilitating the dispersion of the dried coating film during development (i.e., achieving good developability), the drying time is preferably 8 hours or lower, or 4 hours or lower, or 2 hours or lower. From the viewpoint of suppressing the reaction between trace amounts of dispersion medium contained in the dried coating film and the substrate (especially resin substrate), the substrate dissolving and diffusing into the dried coating film, the enhanced bonding between the dried coating film and the substrate, and the deterioration of developability, and from the viewpoint of reducing the content of organic components contained in the metal wiring formed in the laser irradiation process described later, and being able to manufacture low-resistance metal wiring, the drying time is preferably 10 minutes or higher, or 20 minutes or higher, or 30 minutes or higher. The drying pressure is typically atmospheric pressure. From the viewpoint of improving industrial productivity, the pressure can be reduced, preferably based on a gauge pressure of -0.01 MPa or less or -0.03 MPa or less. From the viewpoint of allowing the dispersion medium to slowly evaporate and form a good film during drying, the gauge pressure can preferably be -0.10 MPa or more or -0.08 MPa or more.

[0264] The solid content of the dried coating is preferably 60% by mass or more, or 65% by mass or more, or 70% by mass or more, and preferably 99% by mass or less, or 95% by mass or less, or 90% by mass or less. In this invention, as described in one of the [Examples], the solid content of the dried coating can be measured using a TG-DTA (thermogravimetric differential thermal analysis) apparatus. When the solid content of the dried coating is 60% by mass or more, the volume shrinkage of the dried coating when obtaining metal wiring by laser irradiation is small, the amount of voids in the metal wiring is small, and the sinterability is high. Therefore, wiring with low resistance and small inter-partial deviations in resistance value can be obtained. Furthermore, when the solid content of the dried coating is 60% by mass or more, the adhesion or bonding force between the unexposed portion and the substrate is small, resulting in good developability and removal properties. For example, when the substrate is a resin substrate, the substrate slightly dissolves due to the dispersion medium in the dried coating, and the substrate components diffuse in the dried coating, sometimes causing the unexposed portion to bond firmly to the substrate. However, if the solid content is 60% by mass or more, such diffusion can be avoided. On the other hand, when the solid content of the dried coating is less than 99% by mass, the metal particles and / or metal oxide particles in the dried coating are well dispersed in the developer, which can reduce the amount of residual metal particles and / or metal oxide particles on the substrate after development (i.e., good developability).

[0265] In one embodiment, the arithmetic mean surface roughness Ra of the surface of the structure with the dried coating (i.e., the surface of the dried coating opposite to the substrate side) is 70 nm or more and 10,000 nm or less. From the viewpoint of maximizing the contact area with the developer and improving the dispersibility of the dried coating, the aforementioned arithmetic mean surface roughness Ra is preferably 70 nm or more, or 100 nm or more, or 150 nm or more. From the viewpoint of forming uniform metal wiring with minimal unevenness, the aforementioned arithmetic mean surface roughness Ra is 10,000 nm or less, or 5,000 nm or less, or 1,000 nm or less.

[0266] (Storage process)

[0267] In one embodiment, a storage process can be performed to store the structure 10 with the dried coating for a specified period of time. The storage process is preferably performed in an environment with a storage temperature of 0°C or higher and 40°C or lower, and a relative humidity of 20% or higher and 70% or lower. More preferably, the storage temperature is 0°C or higher and 30°C or lower, and the relative humidity is more preferably 30% or higher and 50% or lower. When storing a structure with a dried coating, deterioration and migration of the coating components can sometimes occur, and migration can lead to short circuits in the metal wiring. When the storage temperature and relative humidity are within the above-mentioned ranges, stable storage of the dried coating can suppress the deterioration and migration of the coating components. The storage pressure is typically atmospheric pressure, but reduced pressure is also possible, preferably based on a gauge pressure of -0.01 MPa or lower, or -0.03 MPa or lower, or -0.05 MPa or lower, or -0.1 MPa or lower. From the viewpoint of maintaining the film quality of the dried coating stably during the storage process, the gauge pressure can preferably be -0.10 MPa or higher or -0.08 MPa or higher.

[0268] From the viewpoint of being able to dissipate heat during the drying process and suppress changes in the coating composition caused by the absorption of moisture from the air by the dried coating, thereby suppressing deviations in the resistance value of the metal wiring formed by laser irradiation in the laser irradiation process described later, the storage time of the structure with the dried coating is preferably 10 minutes or more, or 20 minutes or more, or 30 minutes or more. From the viewpoint of preventing the reaction of trace amounts of dispersion medium contained in the dried coating with the substrate (especially the resin substrate), the dissolution of the substrate and diffusion into the dried coating, which would strengthen the bond between the dried coating and the substrate and lead to deterioration of the developability, the storage time of the structure with the dried coating is preferably 60 days or less, or 30 days or less, or 7 days or less.

[0269] (Laser irradiation process)

[0270] In this process, laser L is irradiated onto the dried coating 2e (step S13), and a conductive portion 2fa, serving as an exposure portion, is formed on a part of the dried coating 2e. Figure 1 (i)). Thus, a structure 20 with conductive parts, having a substrate 1 and an irradiated coating 2f, is formed. Figure 1 (j)), the irradiated coating 2f is disposed on the substrate 1, having a conductive portion 2fa as an exposed portion and a non-conductive portion 2fb as an unexposed portion. The conductive portion 2fa constitutes a metal wiring. For example, when using a dispersion containing copper oxide particles, in the laser irradiation process, the copper oxide in the dried coating is reduced to generate copper particles, and a heat treatment is performed under conditions that produce integration caused by the melting and bonding of the generated copper particles to each other, thereby forming a metal wiring.

[0271] Laser irradiation can be performed using a known laser irradiation device equipped with a laser irradiation section. From the viewpoint of short-time exposure to high-intensity light, allowing the dried coating formed on the substrate to reach a high temperature quickly for firing, lasers are preferred. Lasers allow for short firing times, thus minimizing damage to the substrate and enabling application to substrates with low heat resistance (e.g., resin film substrates), which is advantageous. Furthermore, the laser offers greater freedom in wavelength selection, allowing for wavelength selection that considers the light absorption wavelength of the dried coating and / or the light absorption wavelength of the substrate.

[0272] Furthermore, based on the laser, exposure based on beam scanning is possible, thus making it easy to adjust the exposure range. For example, it is possible to selectively irradiate (delineate) only the target area of ​​the dried coating without using a mask.

[0273] As types of laser light sources, YAG (yttrium aluminum garnet), YVO (yttrium vanadate), Yb (ytterbium), semiconductors (GaAs, GaAlAs, GaInAs), carbon dioxide, etc., can be used. As lasers, not only the fundamental wave can be used, but higher harmonics can also be extracted as needed.

[0274] The center wavelength of the laser is preferably between 350 nm and 600 nm. In particular, when cuprous oxide is used as the metal oxide, cuprous oxide is uniformly reduced due to its good absorption of laser light with a center wavelength in the above range, which can form a low-resistance metal wiring.

[0275] The laser is preferably irradiated onto the dried coating film via an electrical scanner. By scanning the dried coating film with the laser using an electrical scanner, metal wiring of any shape can be obtained.

[0276] From the viewpoint of efficiently performing the desired firing (e.g., reduction of cuprous oxide), the laser irradiation output is preferably 100mW or more, or 200mW or more, or 300mW or more. From the viewpoint of obtaining low-resistance metal wiring by suppressing the damage to the metal wiring caused by ablation due to excessive laser output, the laser irradiation output is preferably 1500mW or less, or 1250mW or less, or 1000mW or less.

[0277] In one approach, the laser can be repeatedly scanned at desired locations on the dried coating. In this case, the amount of laser movement is preferably set to such an amount that adjacent scan lines overlap. Figure 2 This is a schematic diagram illustrating the overlapping irradiation of a laser in the method for manufacturing metal wiring according to this embodiment. (Refer to...) Figure 2The first scan line R1 and its adjacent second scan line R2 overlap. As a result, the heat storage in the overlapping region of the first scan line R1 and the second scan line R2 increases, thus improving the sintering degree of the copper particles. Consequently, the resistance value of the metal wiring can be further reduced.

[0278] The overlap ratio S can be calculated using the following formula, based on the width S1 of the first scan line R1 and the width S2 of the overlap between the second scan line R2 and the first scan line R1 in a direction perpendicular to the scan length direction.

[0279] S = S2 / S1 × 100 (%)

[0280] The overlap ratio is preferably 5% or more, or 10% or more, or 15% or more, and preferably 99.5% or less. By having an overlap ratio of 5% or more, the sintering degree of the metal wiring can be improved, and the amount of smoke generated can be suppressed. By having an overlap ratio of 99.5% or less, the dried coating can be sintered while the laser is moved at an industrially practical speed in a direction perpendicular to the scanning length direction. For example, compared to an overlap ratio below the above range, the sintering degree of the metal wiring can be improved with an overlap ratio within the above range, thus enabling the manufacture of non-brittle and rigid metal wiring. Therefore, for example, even when metal wiring is formed on a flexible substrate and bent, the metal wiring will not break and can follow the flexible substrate.

[0281] (Developing process)

[0282] In this process, the unexposed portion of the dried coating, i.e., the portion other than the metal wiring, is developed and removed using developer 3a (step S14). Water washing is then performed as needed to complete the metal wiring 2g (step S15). Thus, a structure 30 with metal wiring, having a substrate 1 and the metal wiring 2g disposed on the substrate 1, is obtained. Figure 1 (k)). There are no particular limitations on the development method. For example, the structure with conductive parts can be immersed in the developing solution and vibrated, or the structure with conductive parts can be immersed in the developing solution and then irradiated with ultrasound using an ultrasonic device, or the developing solution can be sprayed directly onto the structure with conductive parts by spraying or the like.

[0283] When developing a structure with conductive parts by immersing it in a developer solution, it is preferable to repeat the development process at least twice by changing the developer solution. By changing the developer solution, the dispersion of the coating film in the developer solution can be improved, resulting in better developability.

[0284] In one embodiment, the developing process includes a first developing treatment using the first developing solution of the present invention and a second developing treatment using the second developing solution of the present invention. By appropriately combining two or more developing solutions according to the combination of the first and second developing treatments, the dispersion of the coating in the developing solution can be improved, and unexposed areas can be effectively removed. In this case, it is preferable to use the first and second developing solutions independently (i.e., without mixing) by replacing them.

[0285] The order of the first and second development processes is not limited. From the viewpoint of efficiency in removing metal particles and / or metal oxide particles, it is preferable to perform development in the order of a first development process using the first developer of the present invention, followed by a second development process using the second developer of the present invention. In a preferred embodiment, development is performed using a developer containing additive (A), followed by development using a developer without additive (A). Such development is preferred in terms of reducing the residue of additive (A) on the conductive parts of the structure.

[0286] In addition to the first and second developing processes, the developing process may also include an additional developing process using the additional developing solution of the present invention. The timing of the additional developing process is not limited. For example, if the second developing process is performed after the first developing process, it can be performed before the first developing process, between the first and second developing processes, and / or after the second developing process.

[0287] The compositions of the first developer, the second developer, and the additional developer can be different from each other, or two or more of them can be the same.

[0288] When immersing a structure with conductive parts in a developing solution and irradiating it with an ultrasonic device, the irradiation time is preferably 1 minute or more and 30 minutes or less. Irradiation for more than 1 minute results in good dispersion of the coating film adhering to the substrate, while irradiation for less than 30 minutes can suppress damage to the metal wiring.

[0289] Furthermore, in the developing process, if rinsing with water is performed, followed by rinsing with a developing solution containing additive (A) (in one embodiment, a dispersant), the developability is further improved. If an ultrasonic device is used during water rinsing and / or developing solution rinsing, the developability is further improved.

[0290] In the developing process, a fixture for holding the conductive structure is preferably used. The shape of the fixture is not particularly limited, but it is preferably shaped to prevent contact between the bottom or side walls of the container holding the developer and the conductive structure during the developing operation, or to prevent damage or detachment of the metal wiring caused by contact between the structures when multiple conductive structures are developed simultaneously. The fixture may be, for example, a fixture with recesses for holding each conductive structure individually, or a clamp for holding the structure.

[0291] Figures 3-5 This is a schematic diagram illustrating an example of a fixture for holding a structure with conductive parts during the developing process of the metal wiring manufacturing method of this embodiment. Figure 3 This example shows a fixture 12 with a support portion 12a disposed inside a container 11, on which a structure 20 having a substrate 1 and an irradiated coating 2f (i.e. a film having conductive and non-conductive portions) is placed. Figure 4 This example shows a fixture 22 with a recess 22a arranged inside a container 21, into which a structure 20 with a conductive portion and a three-dimensional substrate 1 and an irradiated coating 2f are inserted. Figure 5 This example shows that the container 31 has a fixture 32 portion that forms a recess 32a, thus also functioning as a fixture, and a structure 20 with a conductive portion having a three-dimensional shape, a substrate 1, and an irradiated coating 2f is inserted into the recess 32a. Figure 4 and Figure 5 The recesses 22a and 32a shown are particularly useful when using a three-dimensional substrate.

[0292] Especially when ultrasonic waves are irradiated onto a structure with conductive parts during development. Figure 3 The bracket portion 12a shown, and Figure 4 and Figure 5 The recesses 22a and 32a shown effectively prevent the structures with conductive parts from contacting each other.

[0293] The fixture is more preferably a structure that can well hold the conductive part of the structure and does not hinder the contact between the developer and the conductive part of the structure, such as a mesh structure.

[0294] Furthermore, the fixture can have a cap or other components or shapes that are desired, such as those for preventing conductive structures from floating in the developer.

[0295] (Regenerated Dispersion Preparation Process)

[0296] In one embodiment, the dispersion of the present invention can be a regenerated dispersion prepared using the developer solution used in the developing process (i.e., the used developer solution). In another embodiment, the method for manufacturing metal wiring includes a regenerated dispersion preparation step after the developing process, in which the regenerated dispersion is prepared using the used developer solution. Recycling the used developer solution for reuse in dispersion preparation reduces waste and leads to lower costs, and is therefore preferred. When the same compound as the dispersion medium used in preparing the dispersion is used as the solvent for the developer solution, the reuse of the developer solution is easier.

[0297] As the used developer, one or more selected from the first developer, the second developer, and the additional developer of the present invention can be used. The used developer preferably includes the first developer, and more preferably the first developer. In particular, when the first developer contains water and the used first developer is regenerated to obtain a regenerated dispersion, in addition to the advantage of resource reuse, the use of water also provides the advantage of regeneration in a cheaper and cleaner environment. Furthermore, in one embodiment, the first developer can be directly reused as a raw material for the dispersion simply by adjusting the concentration as needed after use. When the first developer containing additive (A) is regenerated to obtain a regenerated dispersion containing additive (A) as additive (B) of the present invention, the regenerated dispersion can be obtained without the need for new formulation of the additive, thus enabling more efficient resource recovery.

[0298] Reference Figure 6 and Figure 7 The used developer 3b can be partially or completely reused. In one embodiment, a dispersion, either alone or in combination with unused dispersion 2c and regenerated dispersion 3c, is coated onto substrate 1 (step S11), dried to form a dry coating film (step S12), and after laser irradiation (step S13), developed with developer (step S14), and then, if necessary, completed by washing with water, etc. (step S15). Part or all of the used developer 3b is recovered (step S16) for regeneration processing (step S17) to generate regenerated dispersion 3c for the aforementioned coating.

[0299] Examples of regeneration processes include concentration adjustment (e.g., concentration or dilution), composition adjustment (e.g., adding or removing specified components), purification (e.g., removing residues and other impurities), and dispersion adjustment (e.g., dispersion treatment). Additionally, the composition of the used developer can be analyzed before regeneration. In this case, the regeneration conditions can be determined based on the obtained composition analysis results. If the used developer contains additive (A), the regeneration process is preferably performed under conditions that prevent the additive (A) from deteriorating or being lost.

[0300] More specific examples of regeneration treatment include one or more of the following treatments: (1) concentration, (2) addition of metal particles and / or metal oxide particles, additives (in one manner, dispersants and / or reducing agents), and one or more of the dispersion medium, and (3) dispersion treatment of components in the used developer. The order of these treatments is not particularly limited, but the order of (1), (2), and (3) is preferred.

[0301] (1) Concentration

[0302] There are no particular limitations on the method for concentrating used developer, and examples include: evaporation and concentration by heating and reducing pressure using an evaporator or the like; concentration using a separation membrane; and temporary drying by freeze-drying followed by redispersing the resulting powder in a dispersion medium. Through concentration, the solid content can be adjusted to preferably 5% by mass or more, or 10% by mass or more, and preferably 60% by mass or less, or 50% by mass or less.

[0303] (2) Add

[0304] For used developer, in order to adjust viscosity and / or solids content, it is preferable to add one or more of the aforementioned components as the dispersion components. More specifically, it is preferable to add one or more of the following: metal particles and / or metal oxide particles, additives (in one embodiment, dispersants and / or reducing agents), and dispersion media. In one embodiment, components that are not present in the used developer, or that are present in the used developer but in amounts less than the desired quantity, may be added to the dispersion.

[0305] (3) Dispersed processing

[0306] From the viewpoint of obtaining a high-quality regenerated dispersion, it is preferable to perform a dispersion treatment on the components contained in the used developer. There are no particular limitations on the dispersion method; for example, the used developer can be placed in a container and continuously vibrated with a vibrator to promote dispersion through liquid flow, or a homogenizer can be used for mechanical dispersion. From the viewpoint of the stability of the used developer, the dispersion time is preferably 1 minute or more. A longer dispersion time is preferable, but from the viewpoint of production efficiency, it can be, for example, 1 hour or less. If the above-described (2) is also added, the dispersion treatment is preferably performed after the addition of (2).

[0307] The regenerated dispersion can be prepared using the processes illustrated above. The types of components, the content of each component, and various properties (solid content, viscosity, pH, surface free energy, etc.) of the regenerated dispersion can be the same as those described above regarding dispersions.

[0308] <Kit containing a structure with a dried coating or a structure with conductive parts and a developer>

[0309] One aspect of the invention also provides a kit comprising a structure with a dried coating and a developer. The structure with the dried coating has a substrate and the dried coating of the invention disposed on the surface of the substrate. Specifically, the dried coating, in one aspect, comprises (i) metal particles and / or metal oxide particles, and (ii) an additive (B) (in one aspect, a dispersant and / or a reducing agent). See also... Figure 1 and Figure 6 One type of kit includes a structure 10 with a dried coating and a developer 3a.

[0310] One aspect of the invention also provides a kit comprising a structure with conductive portions and a developer. The structure with conductive portions has a substrate and a film disposed on the surface of the substrate, the film having (1) a conductive region and (2) a non-conductive region. In one aspect, (1) the conductive region corresponds to the exposed portion of the invention, and (2) the non-conductive region corresponds to the unexposed portion of the invention. In one aspect, (1) the conductive region is a copper-containing metal wiring, and (2) the non-conductive region contains cuprous oxide and an additive (B) (in one aspect, a dispersant and / or a reducing agent). See also... Figure 1 and Figure 6 One type of kit includes a structure 20 with conductive parts and a developer 3a.

[0311] In these kits, the arithmetic mean surface roughness Ra of the aforementioned surface of the substrate can be within the range listed in the present invention, in one embodiment being 70 nm or more and 10,000 nm or less. Additionally, in one embodiment, the developer comprises a solvent, either an organic solvent or water or a mixture thereof, and an additive (A) (in one embodiment, a dispersant). In one embodiment, the organic solvent is one or more selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents. In one embodiment, the concentration of additive (A) (in one embodiment, a dispersant) in the developer can be within the range listed with respect to the developer of the present invention, particularly the first developer, in one embodiment being 0.01% by mass or more and 20% by mass or less.

[0312] In these kits, the dried coating and non-conductive portions may each contain a dispersant, preferably a phosphorus-containing organic compound. Additionally, in these kits, the dried coating and non-conductive portions may each contain a reducing agent, preferably hydrazine and / or hydrazine hydrate.

[0313] In one embodiment of these kits, the developer comprises the first developer of the present invention, or comprises both the first developer of the present invention and the second developer of the present invention. The first developer in one embodiment comprises water and / or an alcohol solvent, and in another embodiment further comprises an additive (A), which is contained in an amount of more than 0.01% by mass and less than 20% by mass in one embodiment. In one embodiment, the second developer comprises an organic solvent.

[0314] In one configuration of these kits, the additive (A) in the developer has the same main component as the additive (B) in the structure with the dried coating.

[0315] By combining the structure with the dry coating of the present invention and the developer of the present invention, low-resistance metal wiring is formed by laser irradiation of the dry coating, and the unexposed portions are effectively removed by development without damaging the metal wiring. This allows for the manufacture of a high-quality structure with metal wiring, having a substrate and metal wiring disposed on the surface of the substrate. Furthermore, by combining the structure with conductive portions and the developer as described above, non-conductive portions can be effectively removed by development without damaging the conductive portions of the metal wiring, thus manufacturing a high-quality structure with metal wiring.

[0316] In a preferred embodiment of a kit comprising a structure with a dry coating and a developer, the structure with the dry coating has a substrate and a dry coating disposed on the surface of the substrate, the dry coating comprising (i) metal particles and / or metal oxide particles, (ii) a dispersant and (iii) a reducing agent, the arithmetic mean surface roughness Ra of the surface of the substrate being 70 nm or more and 10000 nm or less, the developer comprising a solvent as an organic solvent or water or a mixture thereof, and a dispersant, the organic solvent being one or more selected from the group consisting of alcohol solvents, ketone solvents, ester solvents and ether solvents, the concentration of the dispersant in the developer being 0.01% by mass or more and 20% by mass or less.

[0317] In a preferred embodiment of the kit comprising a structure with a dried coating and a developer, the developer comprises a first developer and a second developer, the first developer comprising water and / or an alcohol solvent and a dispersant of more than 0.01% by mass and less than 20% by mass, and the second developer comprising an organic solvent.

[0318] In a preferred embodiment of the kit comprising a conductive structure and a developer, the conductive structure has a substrate and a film disposed on the surface of the substrate comprising (1) a conductive region and (2) a non-conductive region, wherein the (1) conductive region is a copper-containing metal wiring, and the non-conductive region comprises cuprous oxide, a reducing agent and a dispersant, the arithmetic mean surface roughness Ra of the substrate surface is 70 nm or more and 10000 nm or less, and the developer comprises a dispersant and a solvent as an organic solvent or water or a mixture thereof, wherein the organic solvent is one or more selected from the group consisting of alcohol solvents, ketone solvents, ester solvents and ether solvents, and the concentration of the dispersant in the developer is 0.01% by mass or more and 20% by mass or less.

[0319] <Metal Wiring Manufacturing System>

[0320] One aspect of the invention also provides a metal wiring manufacturing system. (See reference...) Figure 8 In one embodiment, the metal wiring manufacturing system 100 includes: a coating unit 101 that coats a dispersion comprising metal particles and / or metal oxide particles on the surface of a substrate to form a dispersion layer; a drying unit 102 that dries the dispersion layer to form a structure with a dry coating film having a substrate and a dry coating film disposed on the substrate; a laser irradiation unit 103 that irradiates the dry coating film with a laser to form metal wiring; and a developing unit 104 that uses a developing solution to develop and remove areas of the dry coating film other than the metal wiring.

[0321] The metal wiring manufacturing system of the present invention can be appropriately applied to the metal wiring manufacturing method of the present invention. Therefore, as elements of the metal wiring manufacturing system, elements having the structures or functions illustrated above in the metal wiring manufacturing method can be adopted.

[0322] The coating mechanism 101 may be one or more selected from, for example, a die coater, spin coater, slit coater, bar coater, doctor blade coater, sprayer, dip coater, etc.

[0323] The drying mechanism 102 can be selected from one or more of the following: oven, vacuum dryer, nitrogen-introducing dryer, IR furnace, hot plate, etc.

[0324] The laser irradiation mechanism 103 may, for example, have a laser oscillator (not shown) and an electrical scanner (not shown) that irradiates the coating with the oscillated laser.

[0325] In one embodiment of the metal wiring manufacturing system, the developer (in one embodiment, the first developer of the present invention) comprises an additive (A) and a solvent, either an organic solvent or water or a mixture thereof. In one embodiment, the organic solvent is one or more selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents. In one embodiment, the concentration of additive (A) in the developer is 0.01% by mass or more and 20% by mass or less.

[0326] In one embodiment, the developing mechanism 104 includes: (1) a first developing section 104a, which develops a dried coating using a first developing solution; and

[0327] (2) The second developing section 104b develops the dried coating using a second developing solution. The specific configuration of the first and second developing solutions can be the same as that described in the method for manufacturing metal wiring. In one embodiment, the first developing solution contains water and / or an alcohol solvent; in another embodiment, it also contains an additive (A) (in another embodiment, a dispersant), and in yet another embodiment, the additive (A) is contained in an amount of 0.01% by mass or more and 20% by mass or less. In one embodiment, the second developing solution contains an organic solvent. The positional relationship between the first developing section 104a and the second developing section 104b is not limited, but from the viewpoint of the removal efficiency of metal particles and / or metal oxide particles, such as... Figure 8 As shown, a structure preferably configured to have a conductive portion is supplied to the first developing section 104a and then to the second developing section 104b.

[0328] In one embodiment, the developing unit 104 may have, in addition to having a first developing section 104a and a second developing section 104b, an additional developing section (not shown) for developing a dried coating film using an additional developing solution of the present invention.

[0329] In one embodiment, the first developing section 104a, the second developing section 104b, and any additional developing section, if present, may each have a developing solution and a container for holding the developing solution and the structure with the conductive portion. The first developing section 104a, the second developing section 104b, and any additional developing section, if present, preferably each have a mechanism for promoting development, such as one or more of a vibrator for vibrating the structure with the conductive portion, or an ultrasonic irradiator for irradiating the structure with the conductive portion with ultrasonic waves. In another embodiment, the first developing section 104a, the second developing section 104b, and any additional developing section, if present, may each consist of a developing solution and a sprayer for spraying the developing solution onto the structure with the conductive portion.

[0330] In one embodiment, the metal wiring manufacturing system 100 may further include a developer regeneration mechanism 105 for regenerating the developer recovered from the developing unit 104 to generate a regenerated dispersion. The developer regeneration mechanism 105 may be, for example, a concentration device, a dilution device, a mixing device, an impurity removal device, a dispersion device, etc.

[0331] In addition to the elements mentioned above, metal wiring manufacturing systems can also include additional elements such as substrate conveying mechanisms and substrate cleaning mechanisms as needed.

[0332] <Application Examples>

[0333] As explained above, the method for manufacturing metal wiring according to this embodiment, and the combination of a structure with a dried coating or a structure with conductive parts and a developing solution, enables the manufacture of structures with metal wiring with good developability. The structures with metal wiring according to this embodiment can be appropriately applied, for example, to metal wiring components such as electronic circuit boards (printed circuit boards, RFID, wiring harness replacements in automobiles, etc.), antennas formed in the housings of portable information devices (smartphones, etc.), mesh electrodes (electrode films for electrostatic capacitive touch panels), electromagnetic wave shielding components, and heat dissipation components.

[0334] Example

[0335] The present invention will now be described in more detail through examples and comparative examples, but the present invention is not limited to these examples and comparative examples.

[0336] <Evaluation Methods>

[0337] [Arithmetic mean surface roughness Ra of the substrate]

[0338] The arithmetic mean surface roughness Ra of the coated dispersion surface of the substrate was measured using the following method. A stylus-type surface shape measuring instrument (Bruker DektakXT) and analysis software (Vision64) were used to measure the surface roughness of the substrate. The measurement conditions are as follows.

[0339] Scan type: Standard scan

[0340] Range: 65.5μm

[0341] Profile: Hills & Valleys

[0342] Stylus type: radius 12.5μm

[0343] Needle force: 1mg

[0344] Length: 1000μm

[0345] Duration: 5 seconds

[0346] Resolution: 0.666μm / pt

[0347] After measuring the shape of the substrate surface, surface roughness analysis is performed. The roughness analysis conditions are as follows.

[0348] Filter type: Gaussian regression

[0349] Long cut-off: Long cut-off applications, standard cut-off (0.25mm)

[0350] Roughness profile: Ra

[0351] Parameter calculation: ISO4287

[0352] Sample length also used in the calculation: automatically selected

[0353] The average of the surface roughness values ​​obtained under the above conditions and the surface roughness values ​​measured in a direction orthogonal to the above measurement direction is taken as the arithmetic mean surface roughness Ra value of the substrate.

[0354] [Surface Free Energy]

[0355] The measurement was performed using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., model DM-700) via the suspended drop method.

[0356] [Solubility]

[0357] The following steps were performed using inductively coupled plasma (ICP) luminescence analysis.

[0358] 0.10 g of cuprous oxide powder was added to 40 ml of developing solution and allowed to stand at room temperature (25°C) for 6 hours. The developing solution containing the powder was then filtered through a 0.2 μm filter and diluted 100-fold with 0.10 mol / L nitric acid. The metal concentration (mg / L) of the diluted solution was measured using an ICP-emitting diode (ICP-LED) apparatus (SIINano Technology Co., Ltd., model SPS6100). The concentration of cuprous oxide (mg / L) was calculated from the metal concentration and used as the solubility of cuprous oxide.

[0359] [Resistance value of metal wiring and its change before and after development]

[0360] For a structure with conductive parts and three metal wires formed by laser irradiation, the resistance value of each metal wire is measured by placing a tester 0.5 mm from both ends along the length direction, and the average value R of the three metal wires is calculated. AIn addition, the resistance value of the metal wiring after developing the structure with the conductive portion is also measured in the same manner, and the arithmetic mean value R of the three metal wirings is calculated. B If R B / R A is below 10, it is judged as qualified; if it is below 5, it is judged as good; if it is below 2, it is judged as excellent. On the other hand, when the value of R B / R A is greater than 10, or when the resistance value cannot be measured due to disconnection, it is judged as unqualified.

[0361] [Developability of the structure with the conductive portion]

[0362] The developability is evaluated by the following method. The structure with the conductive portion (i.e., the structure including the copper wiring and the dried coating film not irradiated with laser) produced in the laser irradiation process is immersed in a developing solution (23 °C) in an amount sufficient to immerse the entire structure, and ultrasonic waves are irradiated for a time of 1 minute or more and 30 minutes or less using an ultrasonic device for development.

[0363] A portion of the developed substrate where there is no metal wiring is cut into a 10 mm square, pasted onto an SEM (scanning electron microscope) specimen stage using a carbon tape, and platinum-palladium is coated using a coater (MSP-1S manufactured by Vacuum Devices Co., Ltd.). At this time, the coating conditions are set as follows: process time: 1.5 minutes. For the coated specimen, using an SEM (FlexSEM1000 manufactured by Hitachi High-Technologies Corporation) and an EDX (energy dispersive X-ray analysis) device (AztecOne manufactured by Oxford Instruments), the coating metal residue concentration on the substrate surface is measured. At this time, the conditions of the electron beam are set as follows: acceleration voltage: 5 kV, spot intensity: 80, focus position: 10 mm. After focusing on the specimen surface, the magnification is set to 200 times, and mapping analysis of the entire field of view is performed. The conditions for obtaining the mapping are set as follows: resolution: 256, collection time: 50 frames, process time: high sensitivity, pixel dwell time: 150 μs, frame real-time time: 0:00:08. In addition, the measured elements are set to carbon, oxygen, nitrogen, and the coated (i.e., the metal elements contained in the dispersion) metal elements, and it is specified that platinum and palladium used in the coating are not included in the measured elements. Measurement is performed under the above conditions, and the obtained metal element concentration (mass%) is used as the concentration of the metal remaining on the substrate due to non-developability.

[0364] (Developability evaluation criteria)

[0365] In the developability evaluation of the aforementioned conductive structure, if the concentration of residual metal in the substrate is 20% by mass or less, it is deemed acceptable; if it is 10% by mass or less, it is deemed good; if it is 2.0% by mass or less, it is deemed excellent; and if it is 1.0% by mass or less, it is deemed excellent+. On the other hand, if the concentration of residual metal in the substrate is greater than 20% by mass, or if the coating is clearly not dispersed in the developer during the developing operation and remains on the substrate, it is deemed unacceptable.

[0366] <Example 1>

[0367] [Preparation of Dispersions]

[0368] In a mixed solvent containing 30240g of water and 13976g of 1,2-propanediol (manufactured by Asahi Glass), 3224g of copper(II) monohydrate (manufactured by Nippon Kagaku Sangyo) was dissolved, and 940g of hydrazine hydrate (manufactured by Finecem, Japan) was added. After stirring under a nitrogen atmosphere, the mixture was separated into a supernatant and a precipitate by centrifugation.

[0369] 113g of DISPERBYK-145 (trade name, manufactured by BYK-Chemie Co., Ltd.) (BYK-145) as a phosphorus-containing organic compound and 916g of 1-butanol (manufactured by Sankyo Chemical Co., Ltd.) as a dispersion medium were added to 858g of the obtained precipitate, and the mixture was dispersed using a homogenizer to obtain a dispersion containing cuprous oxide particles containing cuprous oxide (cuprous oxide (I)). At this point, the solid content residue (cuprous oxide particles) after heating the dispersion at atmospheric pressure and 60°C for 4.5 hours was 34.7% by mass.

[0370] The surface free energy of the dispersion was measured, and the results are shown in Table 1.

[0371] [Grinding of substrate]

[0372] The surface of an ABS substrate (as the base material) with a width × depth × thickness of 50 mm × 50 mm × 1 mm was polished using #1000 polishing paper. After polishing, the arithmetic mean surface roughness Ra was measured, and the results are shown in Table 1.

[0373] [Coating and drying of the dispersion]

[0374] The ground substrate was ultrasonically irradiated in ultrapure water for 5 minutes, followed by ultrasonic cleaning in ethanol for 5 minutes. Next, the substrate surface was treated with UV ozone, and then 1 ml of dispersion was dropped onto the surface. The mixture was then spin-coated (300 rpm, 300 seconds) and heated to 60°C for 1 hour to dry. After drying, the sample was stored indoors at normal pressure, room temperature 23°C, and relative humidity 40% for 10 minutes to obtain a sample with a dried coating film formed on the substrate.

[0375] [Laser irradiation]

[0376] The above-mentioned sample was placed in a box with an upper surface made of quartz glass, measuring 200 mm long × 150 mm wide × 41 mm high, with the dried coating film on top. A separation membrane was used to separate compressed air into nitrogen and oxygen. The separated nitrogen gas was blown into the box to maintain an oxygen concentration of less than 0.5% by mass. Next, while moving the focal point of an electric scanner on the substrate surface at a maximum speed of 25 mm / s, a scanning laser (center wavelength 355 nm, frequency 300 kHz, pulsed, output 79 mW) repeatedly irradiated the dried coating film to obtain a copper wire with the desired dimensions of 5 mm long × 1 mm wide. The laser was moved while repeatedly irradiating the surface with an overlap rate of 93.2% in the scanning line width direction. Under the same conditions, two more copper wires were fabricated, resulting in a total of three copper wires.

[0377] [Wiring resistance after laser irradiation]

[0378] The resistance of the metal wiring (i.e., resistance before development) was measured using the method described above. The resistances of the three copper wirings before development, and the average resistance R before development (which is their average value), were then calculated. A As shown in Table 1.

[0379] [Developability of structures with conductive parts]

[0380] The conductive structure, after laser irradiation, was immersed in 50 ml of 2% (w / w) DISPERBYK-145 aqueous solution (first developing solution) (23°C). After 5 minutes of ultrasonic irradiation using an ultrasonic cleaner (ASONE USD-4R), the structure was lifted with tweezers and rinsed with 50 ml of ultrapure water. Then, it was freshly immersed in 50 ml of 5% (w / w) diethylenetriamine aqueous solution (second developing solution) (23°C) and ultrasonically irradiated for 1 minute. The structure was then lifted with tweezers and rinsed with 50 ml of ultrapure water.

[0381] After the development process described above, the copper concentration in the areas of the substrate without metallic wiring was measured using the method described above. The results and evaluations are shown in Table 1.

[0382] The surface free energy of each developer was measured, and the results are shown in Table 1.

[0383] The solubility of copper oxide in each developer was measured, and the results are shown in Table 1.

[0384] [Wire resistance after development]

[0385] After the developing process, the resistance (i.e., post-development resistance) is measured using the method described above. The post-development resistance values ​​of the three copper wires are averaged as R, which is the average of these values. B R B / R A The values ​​and their evaluations are shown in Table 1.

[0386] <Examples 2 and 3>

[0387] The substrate was polished using #2000 polishing paper, the concentration of DISPERBYK-145 in the first developer was set as shown in Table 1, and the ultrasonic irradiation time in the first developer was set to 1 minute. Otherwise, the same procedures as in Example 1 were performed. The evaluation results are shown in Table 1.

[0388] <Example 4>

[0389] The substrate was polished using #2000 polishing paper, the concentration of the first developer DISPERBYK-145 was as shown in Table 1, and the steps of [developability of the structure with conductive parts] were changed as follows. Otherwise, the same operation as in Example 1 was performed.

[0390] [Developability of structures with conductive parts]

[0391] The conductive structure, after laser irradiation, was immersed in 50 ml of a 2% (w / w) DISPERBYK-145 aqueous solution (first developer) (23°C), and ultrasonically irradiated for 1 minute using an ultrasonic cleaner (ASONE USD-4R). The structure was then lifted with tweezers and rinsed with 50 ml of ultrapure water. Next, the structure was immersed again in 50 ml of a 5% (w / w) diethylenetriamine aqueous solution (second developer) (23°C), ultrasonically irradiated for 1 minute, lifted with tweezers, and rinsed with 50 ml of ultrapure water. Finally, the structure was immersed again in 50 ml of a 5% (w / w) diethylenetriamine aqueous solution (third developer) (23°C), ultrasonically irradiated for 1 minute, lifted with tweezers, and rinsed with 50 ml of ultrapure water.

[0392] The evaluation results are shown in Table 1.

[0393] <Example 5>

[0394] The substrate was polished using #2000 abrasive paper. The [dispersion manufacturing] was performed as described below, except that the DISPERBYK-145 used in the first developer was replaced with the same mass of DISPERBYK-118, and the ultrasonic irradiation time in the first developer was set to 1 minute. Otherwise, the same operation as in Example 1 was performed.

[0395] [Preparation of Dispersions]

[0396] In a mixed solvent containing 30240g of water and 13980g of 1,2-propanediol (manufactured by Asahi Glass), 3230g of copper(II) acetate monohydrate (manufactured by Nippon Kagaku Sangyo) was dissolved, and 940g of hydrazine hydrate (manufactured by FineCEM, Japan) was added. After stirring under a nitrogen atmosphere, the mixture was separated into a supernatant and a precipitate by centrifugation.

[0397] 38g of the obtained precipitate was mixed with 87g of a mixing solution, and dispersed using a homogenizer to obtain a dispersion containing cuprous oxide particles (cuprous oxide (I)). It should be noted that the above-mentioned mixing solution was prepared by adding 8g of mixed ethanol (Sankyo Chemical) as a dispersion medium to 131g of DISPERBYK-118 (trade name, manufactured by BYK-Chemie) (BYK-118), a phosphorus-containing organic compound. The solid content (cuprous oxide particles) of the dispersion after heating at atmospheric pressure and 60°C for 4.5 hours was 26.2% by mass.

[0398] The evaluation results are shown in Table 1.

[0399] <Examples 6-9, 12, 18>

[0400] The substrate was polished using #2000 polishing paper, the composition of the developer was changed as shown in Table 1, and the ultrasonic irradiation time in the first developer was set to 1 minute. Otherwise, the same operation as in Example 1 was performed. The evaluation results are shown in Table 1.

[0401] <Example 10>

[0402] The substrate was polished using #2000 polishing paper, the composition of the developer was changed as shown in Table 1, and the ultrasonic irradiation time in the second developer was set to 15 minutes. Otherwise, the same operation as in Example 1 was performed.

[0403] The evaluation results are shown in Table 1.

[0404] <Example 11>

[0405] The substrate was polished using #2000 polishing paper, the composition of the developer was changed as shown in Table 1, and the ultrasonic irradiation time in the second developer was set to 5 minutes. Otherwise, the same operation as in Example 1 was performed.

[0406] The evaluation results are shown in Table 1.

[0407] <Example 13>

[0408] The substrate was polished using #2000 abrasive paper, the ultrasonic irradiation time in the first developing solution was set to 1 minute, and the second developing process was not performed. Otherwise, the same operation as in Example 1 was performed.

[0409] The evaluation results are shown in Table 1.

[0410] <Examples 14 and 15>

[0411] The substrate was polished using #2000 polishing paper, the composition of the developing solution was changed as shown in Table 1, the ultrasonic irradiation time in the first developing solution was set to 1 minute, and the second developing process was not performed. Otherwise, the same operation as in Example 1 was performed.

[0412] The evaluation results are shown in Table 1.

[0413] <Example 16>

[0414] The same operation as in Example 1 was performed without grinding the substrate, changing the composition of the developer as shown in Table 1, and setting the ultrasonic irradiation time in the second developer to 15 minutes.

[0415] The evaluation results are shown in Table 1.

[0416] <Example 17>

[0417] The same operation as in Example 1 was performed without grinding the substrate, changing the composition of the developer as shown in Table 1, and setting the ultrasonic irradiation time in the second developer to 5 minutes.

[0418] The evaluation results are shown in Table 1.

[0419] <Comparative Example 1>

[0420] The same operation as in Example 1 was performed without grinding the substrate, changing the composition of the developer as shown in Table 1, and omitting the second developing step.

[0421] The evaluation results are shown in Table 1.

[0422] <Comparative Example 2>

[0423] The substrate was polished using #2000 polishing paper, the composition of the developing solution was changed as shown in Table 1, the ultrasonic irradiation time in the first developing solution was set to 1 minute, and the second developing process was not performed. Otherwise, the same operation as in Example 1 was performed.

[0424] The evaluation results are shown in Table 1.

[0425] [Table 1] Table 1

[0426]

[0427]

[0428] [Table 2] Table 1 - Continued

[0429]

[0430]

[0431] Industrial availability

[0432] According to the present invention, metal particles and / or metal oxide particles in the unexposed areas can be effectively removed during the developing process, thus providing a low-resistance structure with metal wiring that can, for example, avoid problems such as out-of-pattern precipitation and short circuits caused by migration in subsequent plating processes.

[0433] Such structures with metal wiring can be appropriately used in metal wiring components such as electronic circuit boards, mesh electrodes, electromagnetic wave shielding components, and heat dissipation components.

[0434] Marker description

[0435] R1 First scan line

[0436] R2 Second Scan Line

[0437] S1 width

[0438] S2 width

[0439] 10. Structures with dried coating

[0440] 20. Structures with conductive parts

[0441] 30 Structures with metal wiring

[0442] 1. Substrate

[0443] 2a Supernatant

[0444] 2b Precipitate

[0445] 2c No dispersion used

[0446] 2d dispersion layer

[0447] 2e Dry coating

[0448] 2f Post-irradiation coating

[0449] 2fa conductive part

[0450] 2fb non-conductive part

[0451] 2g metal wiring

[0452] 3a developer

[0453] 3b Used developer

[0454] 3C Regenerated Dispersion

[0455] Containers 11, 21, and 31

[0456] 12, 22, 32 fixture

[0457] 12a support section

[0458] 22a, 32a Recesses

[0459] 100 Metal Wiring Manufacturing System

[0460] 101 Coating Mechanism

[0461] 102 Drying Mechanism

[0462] 103 Laser Irradiation Mechanism

[0463] 104 Developing facility

[0464] 104a First Development Section

[0465] 104b Second Development Section

[0466] 105 Developer Regeneration Mechanism

Claims

1. A method for manufacturing a metal wiring harness, the method comprising: The coating process involves coating a dispersion containing metal particles and / or metal oxide particles onto the surface of a substrate to form a dispersion layer. The drying process dries the dispersion layer to form a structure with a dry coating having the substrate and a dry coating disposed on the substrate; The laser irradiation process involves irradiating the dried coating with a laser to form metal wiring. as well as The developing process uses a developing solution to develop and remove the areas of the dried coating other than the metal wiring. The developing process includes: a first developing treatment that uses a first developing solution to develop and remove the area outside the metal wiring of the dried coating; as well as Following the first developing process, a second developing process is performed on the areas of the dried coating other than the metal wiring, using a second developing solution with a different composition than the first developing solution, to remove the defects. The first developer contains a solvent and an additive (A). The solvent is an organic solvent, water, or a mixture thereof. The organic solvent is one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents. The concentration of additive (A) in the first developer is 0.01% by mass or more and 20% by mass or less. The solubility of the metal particles and / or the metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or the metal oxide particles in the first developing solution.

2. The method for manufacturing metal wiring according to claim 1, wherein, Between the drying process and the laser irradiation process, there is also a storage process, in which the structure is stored in an environment with a storage temperature of 0°C or higher and 40°C or lower, and a relative humidity of 20% or higher and 70% or lower for a specified time.

3. The method for manufacturing metal wiring according to claim 1, wherein, In the drying process, the drying temperature is above 40°C and below 120°C.

4. The method for manufacturing metal wiring according to claim 1, wherein, In the drying process, the drying time is more than 10 minutes and less than 8 hours.

5. The method for manufacturing metal wiring according to claim 1, wherein, The solid content of the dried coating is 60% by mass or more and 99% by mass or less.

6. The method for manufacturing metal wiring according to claim 1, wherein, The arithmetic mean surface roughness Ra of the surface of the substrate is above 70 nm and below 1000 nm.

7. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The additive (A) contains a phosphorus-containing organic compound.

8. The method for manufacturing metal wiring according to claim 7, wherein, The phosphorus-containing organic compounds decompose or evaporate due to light and / or heat.

9. The method for manufacturing metal wiring according to claim 7, wherein, The phosphorus-containing organic compound absorbs light with a central wavelength of 355 nm, 405 nm, 445 nm and / or 450 nm.

10. The method for manufacturing metal wiring according to claim 7, wherein, The phosphorus-containing organic compound contained in the additive (A) is the same as the phosphorus-containing organic compound contained in the dispersion.

11. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The additive (A) is a dispersant.

12. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The additive (A) is a surfactant.

13. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The additive (A) is a reducing agent.

14. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The additive (A) is a complexing agent.

15. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The metal particles and / or the metal oxide particles contain one of the following metals: aluminum, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, ruthenium, rhodium, palladium, silver, indium, tin, antimony, iridium, platinum, gold, thallium, lead, and bismuth, or an alloy containing two or more of these metals, or a mixture containing two or more of these metals.

16. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The content of the metal particles and / or the metal oxide particles in the dispersion, based on the total content of the metal particles and the metal oxide particles, is 0.50% by mass and 60% by mass relative to 100% by mass of the dispersion.

17. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The content of the metal particles and / or the metal oxide particles in the dried coating film, based on the total content of the metal particles and the metal oxide particles, is between 40% and 98% by mass relative to 100% by mass of the dried coating film.

18. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The dispersion contains a dispersion medium.

19. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The dried coating contains a dispersion medium.

20. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The surface free energy of the first developer and the second developer is above 10 mN / m and below 75 mN / m.

21. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The difference between the surface free energy of the first developer and the second developer and the surface free energy of the dispersion is less than 50 mN / m.

22. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The developing process also includes additional developing treatment using additional developing solution.

23. The method for manufacturing metal wiring according to claim 1 or 6, wherein, The development process includes a regeneration dispersion preparation process after the development process, which uses the used developer to prepare the regeneration dispersion, and uses the regeneration dispersion as the dispersion.

24. A method for manufacturing a metal wiring harness, the method comprising: The coating process involves coating a dispersion containing metal particles and / or metal oxide particles and additives (B) onto the surface of a substrate to form a dispersion layer. The drying process dries the dispersion layer to form a structure with a dry coating having the substrate and a dry coating disposed on the substrate; The laser irradiation process involves irradiating the dried coating with a laser to form metal wiring; and The developing process uses a developing solution to develop and remove the areas of the dried coating other than the metal wiring. The developing process includes a first developing treatment using a first developing solution and a second developing treatment using a second developing solution with a different composition from the first developing solution. The solubility of the metal particles and / or the metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or the metal oxide particles in the first developing solution.

25. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The solubility of copper oxide in the second developing solution is higher than that in the first developing solution.

26. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The solubility of copper oxide in the second developer is greater than 0.1 mg / L and less than 10,000 mg / L.

27. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The second developer contains one or more organic solvents selected from the group consisting of amine solvents, alcohol solvents, hydrocarbon solvents, ester solvents and ketone solvents.

28. The method for manufacturing metal wiring according to claim 27, wherein, The amine solvent comprises diethylenetriamine and / or 2-aminoethanol.

29. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The first developer contains water and / or an alcohol solvent.

30. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The first developer contains additive (A) and the dispersion contains additive (B). The main component of additive (A) is the same as the main component of additive (B).

31. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The difference between the surface free energy of the first developer and the surface free energy of the dispersion is greater than 0 mN / m and less than 50 mN / m.

32. The method for manufacturing metal wiring according to claim 1 or 24, wherein, The method further includes, after the developing step, a regenerated dispersion preparation step using the used developing solution to prepare the regenerated dispersion. The regenerated dispersion is used as the dispersion.

33. A kit comprising a structure with a dried coating and a developer, wherein, The structure with a dry coating has a substrate and a dry coating disposed on the surface of the substrate, the dry coating comprising (i) metal particles and / or metal oxide particles, and (ii) an additive (B). The developing solution comprises a first developing solution and a second developing solution with a different composition from the first developing solution. The first developer contains an additive (A) and a solvent, either an organic solvent or water or a mixture thereof. The organic solvent is one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents. The concentration of additive (A) in the first developer is 0.01% by mass or more and 20% by mass or less. The solubility of the metal particles and / or the metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or the metal oxide particles in the first developing solution.

34. The kit according to claim 33, wherein, The additive (B) contains a dispersant and / or a reducing agent.

35. The kit according to claim 33 or 34, wherein, The additive (A) contains a dispersant.

36. The kit according to claim 33 or 34, wherein, The arithmetic mean surface roughness Ra of the structure with the dry coating is above 70 nm and below 1000 nm.

37. The kit according to claim 33 or 34, wherein, The solubility of copper oxide in the second developing solution is higher than that in the first developing solution.

38. A kit comprising a structure with a dried coating and a developer, wherein, The structure with a dry coating has a substrate and a dry coating disposed on the surface of the substrate, the dry coating comprising metal particles and / or metal oxide particles and an additive (B). The developing solution comprises a first developing solution and a second developing solution with a different composition from the first developing solution. The solubility of the metal particles and / or the metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or the metal oxide particles in the first developing solution.

39. The kit of claim 38, wherein, The solubility of copper oxide in the second developing solution is higher than that in the first developing solution.

40. The kit according to claim 38 or 39, wherein, The solubility of copper oxide in the second developer is greater than 0.1 mg / L and less than 10,000 mg / L.

41. The kit according to claim 38 or 39, wherein, The second developer contains one or more organic solvents selected from the group consisting of amine solvents, alcohol solvents, hydrocarbon solvents, ester solvents and ketone solvents.

42. The kit according to claim 38 or 39, wherein, The first developer contains water and / or an alcohol solvent.

43. The kit according to claim 38 or 39, wherein, The first developing solution contains additive (A) and the dried coating contains additive (B). The main component of additive (A) is the same as the main component of additive (B).

44. A metal wiring manufacturing system, comprising: A coating mechanism that coats a dispersion containing metal particles and / or metal oxide particles and additive (B) on the surface of a substrate to form a dispersion layer. A drying mechanism that dries the dispersion layer to form a structure with a dry coating having the substrate and a dry coating disposed on the substrate; A laser irradiation mechanism that irradiates the dried coating with a laser to form metal wiring; and A developing unit comprising: a first developing section for developing and removing areas of the dried coating other than the metal wiring using a first developing solution; and a second developing section for developing and removing areas of the dried coating other than the metal wiring using a second developing solution having a composition different from the first developing solution. in, The first developer contains an additive (A) and a solvent, either an organic solvent or water or a mixture thereof. The organic solvent is one or more solvents selected from the group consisting of alcohol solvents, ketone solvents, ester solvents, amine solvents, and ether solvents. The concentration of additive (A) in the first developer is 0.01% by mass or more and 20% by mass or less. The solubility of the metal particles and / or the metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or the metal oxide particles in the first developing solution.

45. A metal wiring manufacturing system, comprising: A coating mechanism that coats a dispersion containing metal particles and / or metal oxide particles and additive (B) on the surface of a substrate to form a dispersion layer. A drying mechanism that dries the dispersion layer to form a structure with a dry coating having the substrate and a dry coating disposed on the substrate; A laser irradiation mechanism that irradiates the dried coating with a laser to form metal wiring; and The developing unit uses a developing solution to develop and remove the areas outside the metal wiring of the dried coating. in, The developing mechanism includes: a first developing mechanism that uses a first developing solution to develop and remove areas of the dried coating other than the metal wiring; and a second developing mechanism that uses a second developing solution with a different composition than the first developing solution to develop and remove areas of the dried coating other than the metal wiring. The solubility of the metal particles and / or the metal oxide particles in the second developing solution is higher than the solubility of the metal particles and / or the metal oxide particles in the first developing solution.

46. ​​The metal wiring manufacturing system according to claim 45, wherein, The solubility of copper oxide in the second developing solution is higher than that in the first developing solution.

47. The metal wiring manufacturing system according to claim 45 or 46, wherein, The first developer contains water and / or alcohol solvent and 0.01% by mass and less than 20% by mass of additive (A).

48. The metal wiring manufacturing system according to claim 44 or 47, wherein, The main component of additive (A) is the same as the main component of additive (B).

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