JP2014031577A - Composition for forming metal pattern and method for forming metal pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition for forming a metal pattern, in which metal salt and a metal complex are used, and to provide a method for forming a metal pattern.SOLUTION: The composition for forming a metal pattern is prepared by mixing metal salt and/or a metal complex with a reductant. The reductant preferably includes at least one or more of ammonia, a primary amine, a secondary amine, and a tertiary amine, but the mixing may be performed with ethanol, water and the like. A metal pattern (conductive pattern) is formed by printing with the composition for forming a metal pattern on a substrate and radiating a light pulse thereto.

Description

  The present invention relates to a metal pattern forming composition and a metal pattern forming method.

  In order to form a conductive pattern of a semiconductor, metal, etc. on a substrate, for example, an ink pattern is printed on the substrate using an ink composition (conductive ink) in which conductive particles are dispersed, and the conductive pattern in the ink pattern is printed. It is conceivable to sinter the conductive particles into a conductive pattern.

  For example, in the following Patent Document 1, an adhesive is applied to a substrate to coat an adhesive layer, a substrate coated with the adhesive layer is coated with a water repellent layer, and the substrate coated with the adhesive layer and the water repellent layer is coated. A technique for printing a conductive ink, sintering the printed conductive ink, and curing the adhesive layer is disclosed.

  Further, in Patent Document 2 below, metal fine particles are dispersed from a base material provided with an insulating pattern formed of a thermosetting resin so that the metal fine particles adhere to the insulating pattern, and the insulating pattern is heated. An apparatus is disclosed in which an electronic component is manufactured by melting and fixing the fine metal particles on an insulating pattern, and removing the fine metal particles adhering to the surface of a substrate other than the insulating pattern.

  In the method of Patent Document 1, the sintering condition is heating for 1 hour at 200 ° C. (paragraph 0044 of Patent Document 1), and in the method of Patent Document 2, the heating temperature of the insulating pattern is 150 to 200 ° C. ( In the case of heating a conductive pattern or an insulating pattern on a substrate, generally, the substrate that can be used has high heat resistance, such as a bismaleimide triazine compound. Limited to high heat-resistant thermosetting resins such as BT resin.

  Therefore, as described in Patent Documents 3 to 5, there has been an attempt to use an ink composition containing nanoparticles to convert it into a metal wiring by light irradiation or microwave heating. The method using light energy or microwaves for heating can heat only the ink composition (nanoparticles) and may use a resin having a lower heat-resistant temperature than the above resin for the substrate.

JP 2010-75911 A JP 2005-203396 A Special table 2008-522369 International Publication 2010/110969 Pamphlet Special table 2010-528428 gazette

  However, in the conventional sintering technique by light irradiation, the ink composition contains metal or its oxide nanoparticles, and uses a metal salt or metal complex as a main component for forming a metal film. It wasn't.

  An object of the present invention is to provide a metal pattern forming composition using a metal salt or a metal complex as a main component for forming a metal film, and a metal pattern forming method.

  In order to achieve the above object, one embodiment of the present invention is a composition for forming a metal pattern by light irradiation, and is characterized by containing a metal salt and / or a metal complex and a reducing agent.

  The metal of the metal salt and / or metal complex is copper, nickel or cobalt.

  The reducing agent contains at least one of ammonia, primary amine, secondary amine, and tertiary amine.

  In addition, the metal salt and / or the metal complex is an organic acid copper having 4 or less carbon atoms such as copper formate (tetrahydrate), copper acetate, copper trifluoroacetate, copper pentafluoropropionate, copper oxalate and the like. Salt, copper methoxide, copper ketoimine, copper neodecanoate, copper octoate, copper 2-ethylhexanoate, copper nitrate (trihydrate), copper thiosulfate, tetraammine copper (II) nitrate, nickel formate, nickel nitrate (six Hydrate), hexaammine nickel (II) nitrate, cobalt formate, cobalt acetate, cobalt nitrate, and hexaammine cobalt (III) nitrate. More preferably, it contains copper formate (tetrahydrate), copper acetate, copper nitrate (trihydrate), nickel formate, nickel nitrate (hexahydrate), cobalt formate, and cobalt nitrate.

  Another embodiment of the present invention is a method for forming a metal pattern, wherein the composition for forming a metal pattern is printed on a substrate to form the composition pattern, and the composition pattern is pulsed. A metal pattern is formed by heating and baking by irradiating light.

  According to the present invention, a metal pattern can be easily formed using a metal salt or metal complex as a main component without damaging the substrate.

It is a figure for demonstrating the definition of pulsed light.

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described.

  The metal pattern forming composition according to this embodiment is prepared by mixing a metal salt or metal complex and a reducing agent. The metal salt or metal complex may be a powder or a liquid. Further, as the reducing agent, ethanol, water or the like may be mixed in addition to ammonia or an amine solution. In addition, you may use a metal oxide nanoparticle together in the said composition for metal pattern formation.

  The reducing agent preferably contains at least one of ammonia, primary amine, secondary amine, and tertiary amine. Examples of the primary amine include n-butylamine, n-octylamine, 2-ethylhexylamine, and ethanolamine. Examples of the secondary amine include diethylamine, di-n-butylamine, and 2,2′-iminodiethanol. (Diethanolamine) etc. are mentioned, As a tertiary amine, a triethylamine, a tri-n-butylamine, a tri-n-octylamine, a triethanolamine etc. are mentioned, for example.

  Moreover, as said metal salt and a metal complex, the metal salt and metal complex of copper, nickel, or cobalt are mentioned, for example. More specifically, a copper salt of an organic acid having 4 or less carbon atoms (copper formate (tetrahydrate), copper acetate, copper trifluoroacetate, copper pentafluoropropionate, copper oxalate, etc.), copper methoxide, Copper ketimine, copper neodecanoate, copper octoate, copper 2-ethylhexanoate, copper nitrate (trihydrate), copper thiosulfate, tetraammine copper (II) nitrate, nickel formate, nickel nitrate (hexahydrate), Hexaammine nickel (II) nitrate, cobalt formate, cobalt acetate, cobalt nitrate, hexaammine cobalt (III) nitrate and the like can be used. More preferred are copper formate (tetrahydrate), copper acetate, copper nitrate (trihydrate), nickel formate, nickel nitrate (hexahydrate), cobalt formate, and cobalt nitrate. In the case of using a salt or complex of an organic acid, reduction and sintering tend to proceed with less energy when the number of carbon atoms is small, and since the metal content in the salt and complex is high, the number of carbon atoms is one. Alternatively, those having 2 carbon atoms are more preferable, and those having 1 carbon atom are more preferable, but not limited thereto. Copper formate may not be a tetrahydrate, copper nitrate may not be a trihydrate, and nickel nitrate may not be a hexahydrate. When an ammine complex having ammonia as a ligand as a metal complex, such as tetraammine copper (II) nitrate, hexaammine nickel (II) nitrate, hexaammine cobalt (III) nitrate, etc., the ligand ammonia is used. Since it has the function of a reducing agent, it is not necessary to use a reducing agent separately.

  Since these metal salts or metal complexes are used as raw materials for oxide particles and metal particles, they are cheaper than using the corresponding particles, and when producing functional metal compounds such as intermetallic compounds, The reaction can be carried out uniformly in a stoichiometric ratio.

  A metal pattern (conductive pattern) can be formed by printing an appropriate pattern or the like on a substrate using the composition for forming a metal pattern according to this embodiment and irradiating with pulsed light. In order to form the pattern of the metal pattern forming composition on the substrate, for example, by a method such as ink jet printing, screen printing, offset printing, masking printing, etc. Including the case of forming a pattern).

  Examples of the substrate include polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyacrylate, polyolefin, polycycloolefin, polyimide and other resins formed into a film or paper, but the material is not limited to these, and the substrate Any material can be used as long as it can be used. The thickness of the substrate is preferably 10 μm to 3 mm. If the thickness of the substrate is too thin, the film strength is lost, which is not preferable. The thicker is not particularly limited, but if the flexibility is required, the too thick cannot be used. Therefore, the thickness of the film is preferably 10 μm to 3 mm, more preferably 16 μm to 288 μm in consideration of flexibility and availability.

  Next, the pattern of the metal pattern forming composition formed on the substrate is irradiated with pulsed light to reduce and sinter the metal salt and metal complex contained in the metal pattern forming composition into a metal, Form.

  In this specification, “pulse light” means light having a short light irradiation period (irradiation time). When light irradiation is repeated a plurality of times, as shown in FIG. 1, the first light irradiation period (on ) And the second light irradiation period (on) means light irradiation having a period (irradiation interval (off)) in which light is not irradiated. Although FIG. 1 shows that the light intensity of the pulsed light is constant, the light intensity may change within one light irradiation period (on). The pulsed light is emitted from a light source including a flash lamp such as a xenon flash lamp. Using such a light source, the metal nanowires deposited on the substrate are irradiated with pulsed light. When irradiation is repeated n times, one cycle (on + off) in FIG. 1 is repeated n times. In addition, when irradiating repeatedly, when performing the next pulse light irradiation, it is preferable to cool from the base-material side so that a base material can be cooled to room temperature vicinity.

  One irradiation period (on) of the pulsed light is preferably in the range of 5 microseconds to 1 second, more preferably 20 microseconds to 10 milliseconds. If it is shorter than 5 microseconds, the sintering does not proceed and the effect of sintering the pattern of the metal pattern forming composition is lowered. On the other hand, if the time is longer than 1 second, the adverse effect on the substrate or the like due to light deterioration or heat deterioration becomes larger. Irradiation with pulsed light is effective even if performed in a single shot, but can also be performed repeatedly as described above. When it is repeated, the irradiation interval (off) is preferably in the range of 20 to 30 seconds, more preferably 2000 to 5 seconds. If it is shorter than 20 microseconds, it becomes close to continuous light and is irradiated without being allowed to cool after one irradiation, so that there is a possibility that the substrate is heated and the temperature becomes high and deteriorates. On the other hand, if the time is longer than 30 seconds, the cooling is progressed, so that the effect is not completely lost, but the effect of repeated execution is reduced. Note that a light source operating at 0.5 Hz or higher can be used for the irradiation with the pulsed light. Moreover, as the pulsed light, an electromagnetic wave having a wavelength range of 1 pm to 1 m can be used.

  Examples of the present invention will be specifically described below. In addition, the following examples are for facilitating understanding of the present invention, and the present invention is not limited to these examples.

Example 1
Prepare an ink composition (an example of a metal pattern forming composition) using commercially available copper formate tetrahydrate, copper acetate, copper nitrate trihydrate manufactured by Wako Pure Chemical Industries, Ltd. Fabrication was performed.

  Add equimolar amounts of 2-ethylhexylamine (manufactured by Wako Pure Chemical Industries, Ltd.) and ethanol (1.5 times the mass of the compound) or double the amount of each compound. After adding a molar amount of 2,2-iminodiethanol (diethanolamine) (manufactured by Wako Pure Chemical Industries, Ltd.) and ethanol (1.5 times the mass of the compound), a mixer (Awatori Netaro (registered trademark)) ) ARV-310, manufactured by Shinky Corporation) and mixed well to prepare an ink composition. Table 1 shows the appearance of the ink.

Next, each ink composition was placed on a polyimide substrate (thickness 70 μm, Kapton (registered trademark) 300H, manufactured by Toray DuPont) with a 35 μm-thick polyimide tape (manufactured by ASONE, PIST-01), 3 mm wide and 2 cm long. After masking printing to 10 minutes and air drying for 10 minutes, using a PulseForge 3300 manufactured by Novacentrix, 240V, irradiation period (on) 1400 μsec, 3.03 J / cm ² until the entire wiring becomes metallic color several times to several tens of times (each Pulse light was irradiated at intervals of 0.1 second to 2 seconds. The film thickness of the wiring after irradiation with pulsed light was approximately 15 μm as measured by a laser microscope. Table 2 shows the number of pulsed light irradiations and the resistance value per 1 cm after firing. The wiring formed using each ink composition was changed into a copper-colored wiring and energized after irradiation with pulsed light. The resistance value was measured by using a tester (trade name: Digital Multimeter) manufactured by Sanwa Denki Keiki Co., Ltd. with a 1-cm interval on the wiring by the two-terminal method. As a result, all were 30Ω or less, and good conductivity was obtained.

Example 2
A liquid copper neodecanoate ink (an example of a metal pattern forming composition) was prepared at room temperature, and a copper wiring was prepared.

The method for synthesizing the copper neodecanoate ink is as follows. 450 mg (11.25 mmol) of sodium hydroxide was dissolved in 5 ml of water, and under stirring, Versatic 10 (registered trademark) (an isomer mixture of saturated carboxylic acids represented by neodecanoic acid (R ₁ R ₂ R ₃ CCOOH (R ₁ , R ₂ and R ₃ each represents an alkyl group, and the total number of carbon atoms of R ₁ , R ₂ and R ₃ is 8)), and an acid value of 321 mg / g) 2 g was added. The mixture was stirred for 30 minutes, and it was confirmed that there was no separated layer. To this, a solution obtained by dissolving 1.36 g (5.63 mmol) of copper nitrate trihydrate in 3 ml of water was added and stirred. The liberated dark patina oil was extracted with diethyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) and concentrated to prepare a copper neodecanoate ink.

This neodecanoic acid copper ink is placed on a polyimide substrate (thickness 70 μm, Kapton (registered trademark) 300H, manufactured by Toray DuPont) to a width of 3 mm and a length of 2 cm using a 35 μm-thick polyimide tape (manufactured by ASONE, PIST-01). After masking printing and air-drying for 10 minutes, using a PulseForge 3300 manufactured by Novacentrix, 230 V, irradiation time (on) 1200 μsec, and 2.41 J / cm ² until the entire wiring becomes metallic color (5 times pulse light) Irradiation was performed at intervals of 0.1 second to 2 seconds (light irradiation with energy of 12.1 J / cm ² in total). The energy of the irradiated light (12.1 J / cm ² ) is an integrated value of energy values that the apparatus automatically calculates and displays from the voltage applied to the Ryukyu of PulseForge 3300. The film thickness of the wiring after irradiation with pulsed light was approximately 15 μm as measured by a laser microscope. About the produced copper wiring, as a result of measuring the resistance value per 1cm like Example 1, it was 100 (ohm).

Example 3
A copper oxalate powder was synthesized, an ink (an example of a metal layer forming composition) dispersed with this powder, diethanolamine (manufactured by Wako Pure Chemical Industries, Ltd.) and water was prepared, and a copper wiring was prepared.

  The method for synthesizing the copper oxalate powder is as follows. 200 mg (5 mmol) of sodium hydroxide was dissolved in 3 ml of water, and 225 mg (2.5 mmol) of oxalic acid was added with stirring. At this time, although exothermic, it was stirred for 30 minutes as it was, and allowed to cool to room temperature. Although not completely dissolved, 604 mg (2.5 mmol) of copper nitrate trihydrate dissolved in 1 ml of water was added thereto and stirred for 30 minutes. The deposited pale blue precipitate was collected by filtration, washed with water and dried to obtain copper oxalate powder. Next, copper oxalate ink was prepared by dispersing the obtained copper oxalate powder, diethanolamine (manufactured by Wako Pure Chemical Industries, Ltd.) and water in a mass ratio of 1: 0.7: 10.

This copper oxalate ink is masked on a polyimide substrate (thickness 70 μm, Kapton (registered trademark) 300H, manufactured by Toray DuPont) to a width of 3 mm and a length of 2 cm with a 35 μm-thick polyimide tape (manufactured by ASONE, PIST-01). After printing and air-drying for 10 minutes, using a PulseForge 3300 manufactured by Novacentrix, 200 V, irradiation period (on) 1800 μsec, 2.42 J / cm ² , and pulse light 5 times until the entire wiring becomes metallic color (each pulse is 0 (1 second to 2 second intervals) (irradiation with a total energy of 12.1 J / cm ² ). The energy of the irradiated light (12.1 J / cm ² ) is an integrated value of energy values that the apparatus automatically calculates and displays from the voltage applied to the Ryukyu of PulseForge 3300. The film thickness of the wiring after irradiation with pulsed light was approximately 15 μm as measured by a laser microscope. About the produced copper wiring, as a result of measuring the resistance value per 1 cm like Example 1, it was 80 ohms.

Example 4
A metal complex ink (an example of a metal (magnetic material) pattern forming composition) was prepared using a commercially available nickel nitrate hexahydrate powder manufactured by Wako Pure Chemical Industries, Ltd., and a magnetic material was prepared.

After adding a molar amount of 2,2′-iminodiethanol (diethanolamine) (manufactured by Wako Pure Chemical Industries, Ltd.) and 200 μL of ethanol to nickel nitrate hexahydrate, a mixer (Awatori Netaro (registered trademark)) ) ARV-310, manufactured by Shinky Corporation), and mixed well to prepare a Ni-based metal complex ink. The appearance of the metal complex ink is dark blue and transparent. Using this metal complex ink, mask printing is performed on a polyimide substrate in the same manner as in Examples 1 to 3, and in order to keep the shape of the wiring well, a Novacentrix PulseForge 3300 is used, and a multi-pulse (100 μm at 280 V at intervals of 0.01 seconds) is used. Second, 100 μsec, 100 μsec, 200 μsec, 500 μsec, 100 μsec, 100 μsec pulse light irradiation) 10 times, and then a single pulse (250 V, irradiation period (on) 1400 μsec) (each pulse is 0.1 20 times (at intervals of 2 seconds to 2 seconds), light irradiation with a total energy of 101.9 J / cm ² was performed, and wiring was formed. The energy of the irradiated light (101.9 J / cm ² ) is an integrated value of energy values that the apparatus automatically calculates and displays from the voltage applied to the Ryukyu of PulseForge 3300. The film thickness of the wiring after irradiation with pulsed light was approximately 15 μm as measured by a laser microscope. Similar to Example 1, the resistance value of the wiring measured per 1 cm was 540Ω, and it was confirmed that it also attached to the magnet.

Reference example 1
Using commercially available CuO Nanoparticle NanoTek (registered trademark) manufactured by C-I Kasei Co., Ltd., prepare ink with or without amine-based materials, try to produce copper wiring, and measure the reduction power of CuO and the appearance and electrical resistance of CuO Confirmed by.

  Ink A in which CuO nanoparticles (average particle size 48 nm (catalog value)), diethanolamine (manufactured by Wako Pure Chemical Industries, Ltd.) and water are dispersed at a mass ratio of 1: 0.3: 1.2, or CuO nanoparticles and ethanol Ink B, CuO nanoparticles and water dispersed at a mass ratio of 1: 1 were prepared. Each ink was mask-king printed on a polyimide substrate (70 μm thick, Kapton (registered trademark) 300H, manufactured by Toray DuPont) with a 35 μm-thick polyimide tape (manufactured by ASONE, PIST-01) to a width of 3 mm and a length of 2 mm. After air-drying for 1 minute, pulse light was irradiated a plurality of times (each pulse at intervals of 0.1 second to 2 seconds) using a PulseForge 3300 manufactured by Novacentrix until the entire wiring was discolored. Table 3 shows the total energy at the time of wiring firing and the resistance value of the wiring per 1 cm measured in the same manner as in Example 1. The total energy is an integrated value of energy values that the apparatus automatically calculates and displays from the voltage applied to the Ryukyu of PulseForge 3300. When an amine-based substance is used, it has the strongest reducing power and a low resistance value is obtained.

Claims (7)

  A composition for forming a metal pattern by light irradiation, comprising a metal salt and / or a metal complex and a reducing agent.   The metal pattern forming composition according to claim 1, wherein a metal of the metal salt and / or metal complex is copper, nickel, or cobalt.   The metal pattern forming composition according to claim 1 or 2, wherein the reducing agent contains at least one of ammonia, primary amine, secondary amine, and tertiary amine.   The metal salt and / or the metal complex is a copper salt of an organic acid having 4 or less carbon atoms, copper methoxide, copper ketimine, copper neodecanoate, copper octoate, copper 2-ethylhexanoate, copper nitrate (trihydrate) ), Copper thiosulfate, tetraammine copper (II) nitrate, nickel formate, nickel nitrate (hexahydrate), hexaammine nickel (II) nitrate, cobalt formate, cobalt acetate, cobalt nitrate, hexaammine cobalt (III) nitrate The metal pattern forming composition according to any one of claims 1 to 3, comprising at least one.   The copper salt of an organic acid having 4 or less carbon atoms is at least one of copper formate (tetrahydrate), copper acetate, copper trifluoroacetate, copper pentafluoropropionate, and copper oxalate. A metal pattern forming composition.   The metal salt and / or metal complex is at least one of copper formate (tetrahydrate), copper acetate, copper nitrate (trihydrate), nickel formate, nickel nitrate (hexahydrate), cobalt formate, and cobalt nitrate. The composition for forming a metal pattern according to claim 4, comprising:   A metal pattern forming composition according to any one of claims 1 to 6 is printed on a substrate to form the composition pattern, and the composition pattern is heated and fired by irradiating pulse light. And forming a metal pattern.

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