TW201510273A - Composition for copper film formation and copper film production method using same - Google Patents

Abstract

Provided is a composition for copper film formation that: contains 0.1-3.0 mol/kg of a copper formate or a hydrate thereof, a diol compound that is represented by formula (1), and a piperidine compound that is represented by formula (2); and that has a diol compound content in the range of 0.1-6.0 mol/kg and a piperidine compound content in the range of 0.1-6.0 mol/kg when the content of the copper formate or the hydrate thereof is 1 mol/kg. The composition for copper film formation is in a solution state that does not contain any solid phases such as fine particles, and makes it possible to obtain a copper film having sufficient conductivity by applying said composition on a substrate and heating at a temperature of less than 200 DEG C.

Description

Composition for forming copper film and method for producing copper film using same

The present invention relates to a composition for forming a copper film for forming a copper film on various substrates, and a method for producing a copper film using the same.

A large number of reports have been made for forming a conductive layer or wiring using copper as a conductor by a coating thermal decomposition method (MOD (Metal-Organic Decomposition) method) or a fine particle dispersion coating method which is a liquid process.

For example, in Patent Documents 1 to 4, a series of methods for producing a copper film-forming article are proposed, in which a mixture of copper hydroxide, copper organic acid, and a polyhydric alcohol as an essential component is applied to various substrates to be non-oxidized. Heat to a temperature above 165 ° C in a neutral environment. Further, copper formate is disclosed as an organic acid copper used in the liquid process, and diethanolamine and triethanolamine are disclosed as a polyol.

Patent Document 5 proposes a metal paste containing silver fine particles and an organic compound of copper which can form a metal film excellent in solder heat resistance on a base electrode. Copper formate is disclosed as an organic compound for copper of the paste, and diethanolamine is disclosed as an amine compound which reacts with the organic compound of copper to gelatinize it.

Patent Document 6 proposes a metal salt mixture for forming a metal pattern of a circuit. Further, among the components constituting the mixture, copper formate is used as a metal salt, and diethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, and an organic solvent are disclosed. As an organic component, porphyrin reveals pyridine as a metal ligand.

Patent Document 7 discloses a low temperature containing copper formate and a 3-dialkylaminopropane-1,2-diol compound which can be thermally decomposed after printing, such as formation of wiring for electronic devices. Decomposable copper precursor composition.

Patent Document 8 discloses a composition for forming a copper thin film containing copper formate and an alkanolamine which can be used in the above liquid process. Further, monoethanolamine, diethanolamine, and triethanolamine are exemplified as the alkanolamine.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 1-168865

[Patent Document 2] Japanese Patent Laid-Open No. Hei 1-168866

[Patent Document 3] Japanese Patent Laid-Open No. Hei 1-168067

[Patent Document 4] Japanese Patent Laid-Open No. Hei 1-168868

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2007-35353

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2008-205430

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2009-256218

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2010-242118

Here, in order to inexpensively manufacture a fine wiring or film in a liquid process using a composition for forming a copper film, it is desirable to provide a composition satisfying the following requirements. In other words, it is desirable to provide a solution type which does not contain a solid phase such as fine particles, a copper film which is excellent in conductivity, can be converted into a copper film at a low temperature, has good coatability, is free from generation of precipitates such as metallic copper, and is easily controlled by one time. The film thickness obtained by coating is particularly desirable by heating at less than 200 ° C On the other hand, a copper film having excellent conductivity is formed. However, a composition for forming a copper film which satisfies all of the above requirements is not known.

Accordingly, an object of the present invention is to provide a composition for forming a copper film which satisfies all of the above requirements. More specifically, an object of the present invention is to provide a solution for forming a copper film which does not contain a solid phase such as fine particles, which can be obtained by coating on a substrate and heating at less than 200 ° C. Conductive copper film.

The present inventors have repeatedly studied in view of the above-described actual conditions, and as a result, it has been found that a composition for forming a copper film containing copper formate or a hydrate thereof, a diol compound having a specific structure, and a piperidine compound having a specific structure at a specific ratio is satisfied. The above requirements require performance to complete the present invention.

In other words, the present invention provides a composition for forming a copper film, which comprises copper formate of 0.1 to 3.0 mol/kg or a hydrate thereof, a diol compound represented by the following general formula (1), and the following general The piperidine compound represented by the formula (2), when the content of the copper formate or the hydrate thereof is 1 mol/kg, the diol compound is contained in the range of 0.1 to 6.0 mol/kg. The above piperidine compound is contained in the range of 0.1 to 6.0 mol/kg.

(In the above general formula (1), R ¹ and R ² each independently represent a hydrogen atom, a methyl group, or an ethyl group)

(In the above general formula (2), R ³ represents a methyl group or an ethyl group, and m represents 0 or 1)

Moreover, the present invention provides a method for producing a copper film, comprising the steps of: applying the composition for forming a copper film to a substrate, and the substrate coated with the composition for forming a copper film; The step of heating to less than 200 ° C to form a copper film.

According to the present invention, there is provided a copper film-forming composition which can be obtained by coating on a substrate and heating at a temperature of less than 200 ° C to obtain a copper film having sufficient conductivity, and which is free from particles and the like. The solution of the phase.

One of the characteristics of the composition for forming a copper film of the present invention is that copper formate is used as a copper film precursor (Precursor). The copper formate used in the composition for forming a copper film of the present invention may be an anhydrate or a hydrate. Specifically, anhydrous copper formate (II), copper (II) formate dihydrate, copper (II) formate tetrahydrate, or the like can be used. The copper formate may be directly mixed or mixed as an aqueous solution, an organic solvent solution, or an organic solvent suspension.

The content of copper formate in the composition for forming a copper film of the present invention may be appropriately adjusted depending on the thickness of the copper film to be produced. The content of copper formate is 0.1 to 3.0 mol/kg, preferably 1.0 to 2.5 mol/kg. Here, "mol (mol) / kg" in the present invention means "the amount of solute dissolved in 1 kg of the solution (mole)". For example, copper (II) formate When the amount of 153.58 g of copper formate is contained in 1 kg of the composition for forming a copper film of the present invention, it is 1.0 mol/kg.

The diol compound represented by the following general formula (1) which is a component constituting the composition for forming a copper film of the present invention is characterized by having an amine group. As a result of investigations by the inventors of the present invention, it has been found that the diol compound functions as a co-solvent for copper formate and copper formate hydrate. Further, it has been found that the diol compound exhibits an effect of suppressing the generation of a precipitate such as metallic copper in the composition for forming a copper film, and further improving the conductivity of the formed copper film.

(In the above general formula (1), R ¹ and R ² each independently represent a hydrogen atom, a methyl group, or an ethyl group)

Examples of the diol compound represented by the above formula (1) include the following compounds No. 1 to No. 6.

Among the above-exemplified diol compounds, 2-amino-2-methyl-1,3-propanediol (No. 1) can be converted into a copper film at a lower heating temperature, and formed by a composition for forming a copper film. The copper film is particularly excellent in electrical conductivity.

The content of the diol compound in the composition for forming a copper film of the present invention is in the range of 0.1 to 6.0 mol/kg when the content of copper formate or a hydrate thereof is 1 mol/kg. When the amount of 1 mol/kg is less than 0.1 mol/kg with respect to copper formate or its hydrate, the conductivity of the obtained copper film becomes insufficient. On the other hand, when it exceeds 6.0 mol/kg, coatability will deteriorate, and a uniform copper film will not be obtained. A more preferred range is 0.2 to 5.0 m/kg. Further preferably, the range is from 0.5 to 2.0 mol/kg. Further, the above diol compounds may be used singly or in combination of two or more.

The composition for forming a copper film of the present invention contains a piperidine compound represented by the following general formula (2) as an essential component. By containing the piperidine compound, the coating property for the copper film-forming composition can be improved, and the generation of precipitates such as metallic copper can be suppressed. Further, by using a combination of copper formate or copper formate and a diol compound represented by the above general formula (1), a copper film which can be converted into a copper film by heating at less than 200 ° C can be obtained. Composition.

(In the above general formula (2), R ³ represents a methyl group or an ethyl group, and m represents 0 or 1)

Examples of the piperidine compound represented by the above formula (2) include the following compounds No. 7 to No. 13.

Among the above-mentioned piperidine compounds, 2-methylpiperidine (No. 8) is particularly preferably used. By using 2-methylpiperidine, a composition for forming a copper film having excellent coating properties and suppressing the occurrence of precipitation of metal copper or the like can be obtained.

The content of the above piperidine compound in the composition for forming a copper film of the present invention is in the range of 0.1 to 6.0 mol/kg when the content of copper formate or a hydrate thereof is 1 mol/kg. When the amount of 1 mol/kg of copper formate or its hydrate is less than 0.1 mol/kg, the coatability is deteriorated, and a uniform copper film cannot be obtained. On the other hand, if it exceeds 6.0 mol/kg, the conductivity of the obtained copper film becomes insufficient. A more preferred range is 0.2 to 5.0 m/kg. Further preferably, the range is from 0.5 to 2.0 mol/kg. Further, the above piperidine compounds may be used singly or in combination of two or more kinds.

Further, the above diol compound in the composition for forming a copper film of the present invention The sum of the contents of the above piperidine compound is preferably in the range of 0.5 to 2.0 mol/kg when the content of copper formate or a hydrate thereof is 1 mol/kg. Thereby, the coating property of the composition for forming a copper film, the conductivity of the obtained copper film, and the effect of suppressing the generation of precipitates such as metallic copper are excellent, which is preferable. If it is less than 0.5 mol/kg, there is a case where a precipitate such as metallic copper is generated. On the other hand, if it is more than 2.0 mol/kg, the coatability may be deteriorated. A more preferred range is from 0.8 to 1.5 moles/kg.

Further, the diol compound and piperidine in the composition for forming a copper film of the present invention The concentration ratio of the compound is not particularly limited. When the diol compound is 1 mol/kg, the piperidine compound is preferably in the range of 0.5 to 1.5 mol/kg. When the piperidine compound is 1 mol/kg (substantially equivalent to the diol compound), the stability of the solution is good, and a copper film excellent in electrical characteristics can be obtained, which is particularly preferable.

The composition for forming a copper film of the present invention contains copper formate or hydrated thereof The compound, the specific diol compound, and the specific piperidine compound are essential components. However, any component other than the essential components may be contained within a range that does not impair the effects of the present invention. The optional component may, for example, be an organic solvent; an additive for thickening the film thickness of the obtained copper film; an additive for imparting stability to a composition for forming a copper film, such as a gelation preventing agent or a stabilizer; A foaming agent, a tackifier, a thixotropic agent, a leveling agent, and the like, an additive for improving the coating property of a composition for forming a copper film, a filming aid such as a combustion aid or a crosslinking assistant.

The above organic solvent may be any of the above copper formate (or a hydrate thereof) and a diol. The compound and the piperidine compound may be dissolved in a stable manner. The organic solvent may be a single composition or a mixture. Examples of the organic solvent which can be used in the composition for forming a copper film of the present invention include an alcohol solvent, a glycol solvent, a ketone solvent, an ester solvent, an ether solvent, an aliphatic or alicyclic hydrocarbon system. Solvent, aromatic hydrocarbon solvent, with cyanide Base hydrocarbon solvent, other solvents, and the like.

Examples of the alcohol-based solvent include methanol, ethanol, propanol, and isopropyl alcohol. Alcohol, 1-butanol, isobutanol, 2-butanol, tert-butanol, pentanol, isoamyl alcohol, 2-pentanol, neopentyl alcohol, third pentanol, hexanol, 2-hexanol, Heptanol, 2-heptanol, octanol, 2-ethylhexanol, 2-octanol, cyclopentanol, cyclohexanol, cycloheptanol, methylcyclopentanol, methylcyclohexanol, methyl ring Heptanol, benzyl alcohol, ethylene glycol monoacetate, ethylene glycol monoethyl ether, ethylene glycol monophenyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether, 2-(2-methoxyethoxy)ethanol, 2-(N , N-dimethylamino)ethanol, 3-(N,N-dimethylamino)propanol, and the like.

Examples of the glycol solvent include ethylene glycol, propylene glycol, and 1,2- Butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, isoprenediol (3-methyl-1,3-butanediol) ), 1,2-hexanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,2-octanediol, octanediol (2-ethyl-1, 3-hexanediol), 2-butyl-2-ethyl-1,3-propanediol, 2,5-dimethyl-2,5-hexanediol, 1,2-cyclohexanediol, 1, 4-cyclohexanediol, 1,4-cyclohexanedimethanol, and the like.

Examples of the ketone solvent include acetone, methyl ethyl ketone, and methyl group. Butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, methyl cyclohexanone and the like.

Examples of the ester solvent include methyl formate, ethyl formate, and B. Methyl ester, ethyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, dibutyl acetate, tert-butyl acetate, amyl acetate, isoamyl acetate, triamyl acetate, acetic acid Phenyl ester, methyl propionate, ethyl propionate, isopropyl propionate, butyl propionate, isobutyl propionate, second butyl propionate, tert-butyl propionate, amyl propionate, C Isoamyl acid ester, third amyl propionate, phenyl propionate, methyl 2-ethylhexanoate, ethyl 2-ethylhexanoate, propyl 2-ethylhexanoate, 2-ethylhexanoic acid Isopropyl ester, butyl 2-ethylhexanoate, methyl lactate, ethyl lactate, methyl methoxypropionate, methyl ethoxypropionate, ethyl methoxypropionate, ethoxypropionic acid Ethyl ester, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monoisopropyl ether Acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoisobutyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol Monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monoisopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol Monoisobutyl ether acetate, propylene glycol monobutyl ether acetate, butanediol monomethyl ether acetate, butanediol monoethyl ether acetate, butanediol monopropyl ether acetate, butanediol Monoisopropyl ether acetate, butanediol monobutyl ether acetate, butanediol monobutyl ether acetate, butanediol monoisobutyl ether acetate, butanediol monoterpene ether Acid ester, ethyl acetate methyl acetate, ethyl acetate Ethyl oxobutanoate side, side-oxobutyrate, [gamma] butyrolactone, delta-lactone.

Examples of the ether solvent include tetrahydrofuran and tetrahydropyran. Porphyrin, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dibutyl ether, diethyl ether, two Alkane, etc.

Examples of the aliphatic or alicyclic hydrocarbon-based solvent include pentane and hexane. Cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, decahydronaphthalene, solvent petroleum brain, and the like.

Examples of the aromatic hydrocarbon solvent include benzene, toluene, ethylbenzene, xylene, 1,3,5-trimethylbenzene, diethylbenzene, cumene, isobutylbenzene, isopropyltoluene, and tetrahydronaphthalene. .

Examples of the hydrocarbon solvent having a cyano group include 1-cyanopropane, 1-cyanobutane, 1-cyanohexane, cyanocyclohexane, cyanobenzene, and 1,3-dicyanopropane. 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, 1,4-dicyanobenzene, and the like.

As other solvents, N-methyl-2-pyrrolidone and dimethyl amide are mentioned. Bismuth, dimethylformamide.

In the present invention, among the above organic solvents, an alcohol solvent or a glycol system The solvent and the ester solvent are relatively inexpensive, and exhibit sufficient solubility for the solute, and further exhibit good coating properties as a coating solvent for various substrates such as a ruthenium substrate, a metal substrate, a ceramic substrate, a glass substrate, and a resin matrix. Therefore, it is better. Among them, an alcohol solvent is particularly preferable because it has high solubility in a solute.

The content of the above organic solvent in the composition for forming a copper film of the present invention It is not particularly limited, and may be appropriately adjusted depending on the thickness of the copper film to be formed or the method for producing the copper film. For example, when a copper film is produced by a coating method, it is preferably used in an amount of 100 parts by mass relative to copper formate (in the case of copper formate hydrate, in the same manner as in the formic acid copper). Parts ~ 5,000 parts by mass. When the amount of the organic solvent is less than 0.01 parts by mass, there may be a case where the obtained copper film is cracked or the coating property is deteriorated. In addition, as the ratio of the organic solvent increases, the copper film obtained becomes thinner, and therefore it is preferably not more than 5,000 parts by mass in terms of productivity. More specifically, in the case of producing a copper film by a spin coating method, it is preferred to use 20 parts by mass to 1,000 parts by mass of the organic solvent with respect to 100 parts by mass of copper formate. Moreover, in the case of producing a copper film by a screen printing method, it is preferable to use 0.01 to 20 parts by mass of the organic solvent with respect to 100 parts by mass of copper formate.

As an additive for thickening the film thickness of the obtained copper film, for example, Use copper acetate or its hydrate. By adding such an additive, the copper concentration in the composition for forming a copper film can be made rich, and a copper film having a thick film thickness can be obtained. For example, the content of copper acetate or a hydrate thereof when copper acetate or a hydrate thereof is used as the additive is not particularly limited, and may be appropriately adjusted depending on the thickness of the copper film to be formed. The concentration ratio of copper formate or a hydrate thereof to copper acetate or a hydrate thereof is not particularly limited, and is preferably a group for forming a copper film. 40% by mass or more of all copper in the product is added by copper formate. The content of copper acetate or a hydrate thereof is preferably in the range of 0.1 to 2.0 mol/kg, more preferably 0.5 to 1.5 mol, in the case where copper formate or a hydrate thereof is set to 1 mol/kg. /kg range. Further, since the ratio of the concentration of copper formate to copper acetate (mol/kg) is about 1:1, a copper film excellent in electrical characteristics can be obtained, which is particularly preferable.

As an additive for imparting stability to a composition for forming a copper film, Listed: alkanolamines represented by diethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-aminopropyldiethanolamine; represented by 3-dimethylamine-1,2-propanediol A diol compound having one or more amine groups. When N-methyldiethanolamine is added as a stabilizer, the effect of suppressing the formation of a precipitate such as metallic copper is high, which is particularly preferable.

Next, a method of producing a copper film of the present invention will be described. The invention The method for producing a copper film has the steps of applying the composition for forming a copper film of the present invention described above to a substrate (coating step), and heating the substrate coated with the composition for forming a copper film. A step of forming a copper film to less than 200 ° C (film formation step). Further, before the film formation step, a drying step of maintaining the substrate at 50 ° C or higher and less than 150 ° C to volatilize a low boiling point component such as an organic solvent may be further provided. Further, after the film forming step, an annealing step of maintaining the conductivity of the copper film while maintaining the substrate at 100 ° C or higher and less than 200 ° C may be further provided.

As a coating method in the said coating process, the spin coating is mentioned. Method, dipping method, spray coating method, spray coating method, shower coating method, curtain coating method, roll coating method, knife coating method, bar coating method, slit coating method, screen printing method, gravure printing Method, lithography, inkjet method, brush painting, and the like.

Moreover, in order to obtain a desired film thickness, the above coating step can be carried out to any The steps are repeated multiple times. For example, all of the steps from the coating step to the film forming step may be repeated a plurality of times, or the coating step and the drying step may be repeated a plurality of times.

The environment of the above drying step, film forming step, and annealing step is usually also Any of an inert gas environment and an inert gas environment. A copper film having more excellent conductivity can be obtained in a reducing gas atmosphere. Examples of the reducing gas include hydrogen gas, and examples of the inert gas include helium gas, nitrogen gas, and argon gas. The inert gas can also be used as a diluent gas for the reducing gas. In addition, in each step, plasma or laser can be applied or irradiated; a laser; a xenon lamp, a mercury lamp, a mercury xenon lamp, a xenon flash lamp, an argon flash lamp, a xenon lamp, and the like; and energy other than heat such as radiation.

[Examples]

Hereinafter, the present invention will be described in further detail by way of examples. However, the present invention is not limited by the following examples and the like.

<Composition for forming a copper film> [Examples 1 and 2] (no organic solvent)

The compounds described in Table 1 were prepared so as to have a concentration (mol/kg, mass%) of the numerical values in parentheses, and the compositions 1 and 2 for forming a copper film were obtained. In addition, the concentration of each compound described in Table 1 is the amount (hereinafter the same) of 1 kg of the composition for forming a copper film to be produced.

[Examples 3 to 9] (the presence of an organic solvent)

The compound described in Table 2 was prepared so as to have a concentration (mol/kg) of the numerical value in parentheses, and the composition for forming a copper film 3 to 9 was obtained. Furthermore, all of the remaining components were made into ethanol.

[Comparative Examples 1 to 4] (organic solvent is present)

The compounds described in Table 3 were formulated so as to have a concentration (mol/kg) of values in parentheses, respectively, to obtain comparative compositions 1 to 4. Furthermore, all of the remaining components were made into ethanol.

<Manufacture of copper film> [Examples 10 to 18]

A copper thin film was produced by a coating method using the copper film forming compositions 1 to 9, respectively. Specifically, each of the copper film-forming compositions was cast on a glass substrate (Eagle XG (trade name), manufactured by Corning Incorporated) for a liquid crystal screen. Thereafter, each of the copper film-forming compositions was applied by spin coating at 500 rpm for 5 seconds and at 2,000 rpm for 20 seconds. Next, using a hot plate, it was dried at 100 ° C for 30 seconds in the atmosphere. The dried glass substrate was heated at 160 ° C for 20 minutes in an argon atmosphere using an infrared heating furnace (RTP-6 (trade name), manufactured by ULVAC Corporation) to obtain a copper thin film. Further, the flow condition of the argon gas at the time of firing was set to 300 mL/min, and the temperature increase rate was set to 160 ° C / 30 seconds. In addition, since the copper concentration of the composition 3 for forming a copper film is low, if only one casting-baking operation is performed, the copper film obtained is thin, and it is not possible to sufficiently ensure the surface resistance value to be measured. The required film thickness. Therefore, in Example 12 in which the composition 3 for forming a copper film was used, a two-time casting-baking operation was performed to form a copper thin film having a sufficient film thickness.

[Comparative Examples 5 to 8]

A copper thin film was produced by a coating method using Comparative Compositions 1 to 4, respectively. Specifically, first, each comparative composition was cast on a glass substrate (Eagle XG (trade name), manufactured by Corning Incorporated) for a liquid crystal screen. Thereafter, each comparative composition was applied by spin coating at 500 rpm for 5 seconds and at 2,000 rpm for 20 seconds. Next, using a hot plate, it was dried at 100 ° C for 60 seconds in the atmosphere. The dried glass substrate was heated at 210 ° C for 20 minutes in an argon atmosphere using an infrared heating furnace (RTP-6 (trade name), manufactured by ULVAC Corporation) to obtain a copper thin film. Further, the flow condition of the argon gas at the time of firing was set to 300 mL/min, and the temperature increase rate was set to 210 ° C / 30 seconds.

<evaluation> [Measurement of surface resistance value]

The surface resistance values of the respective copper thin films on the glass substrates produced in Examples 10 to 18 and Comparative Examples 5 to 8 were measured using a resistivity meter (Loresta GP (trade name), manufactured by Mitsubishi Chemical Analytech Co., Ltd.). The measured surface resistance values are shown in Table 4.

As shown in Table 4, in Comparative Examples 5 to 8, calcination was carried out at 210 ° C, but it was not possible. A copper film exhibiting conductivity is formed. On the other hand, in Examples 10 to 18, it was confirmed that a copper thin film having excellent electrical characteristics was formed even when it was fired at 160 °C. In the above case, it was confirmed that the copper film having good electrical properties can be formed even when the composition for forming a copper film of Examples 1 to 9 is used for firing at a low temperature of less than 200 ° C.

Claims (4)

A composition for forming a copper film, comprising a copper formate of 0.1 to 3.0 mol/kg or a hydrate thereof, a diol compound represented by the following general formula (1), and the following general formula (2); The piperidine compound is represented by the above-mentioned diol compound in the range of 0.1 to 6.0 mol/kg when the content of the above copper formate or its hydrate is 1 mol/kg, and is 0.1 to 6.0 mol. The ear/kg range contains the above piperidine compound, (In the above general formula (1), R ¹ and R ² each independently represent a hydrogen atom, a methyl group, or an ethyl group) (In the above general formula (2), R ³ represents a methyl group or an ethyl group, and m represents 0 or 1). The composition for forming a copper film according to the first aspect of the invention, wherein the diol compound is 2-amino-2-methyl-1,3-propanediol. The composition for forming a copper film according to claim 1 or 2, wherein the piperidine compound is 2-methylpiperidine. A method for producing a copper film, comprising the steps of: applying a composition for forming a copper film according to any one of claims 1 to 3 to a substrate; and coating the copper film The step of forming the copper film by heating the substrate of the composition to less than 200 °C.