JP2008013696A - Metallic film-forming composition and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metallic film-forming composition capable of inhibiting developing deposits on the surface of metallic film after baking. <P>SOLUTION: The metallic film-forming composition comprises a water-soluble polymer and a metal compound, wherein the content of metallic substances except the metal compound is 50 ppm or less. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a metal film forming composition and a method for producing the same. More specifically, the present invention relates to a metal film forming composition material that can be used in the field of manufacturing electronic devices and a method for manufacturing the same.

In an electronic device, a metal film is formed on a substrate or the like when a wiring or the like is formed. As a method for forming the metal film, there is a method in which a metal compound-containing resin composition is applied and then the composition is baked (see Patent Documents 1 and 2).
JP-A-8-176177 JP 2004-96106 A

  However, some precipitates may be generated on the surface of the fired metal film. When precipitates are generated on the surface of the metal film, the dimensions of the metal wiring pattern may be out of order, and the electrical characteristics of the formed device may deteriorate.

  In view of the above problems, an object of the present invention is to provide a composition for forming a metal oxide film capable of suppressing the generation of precipitates deposited on the surface of the fired metal film.

  The present inventors have determined that the precipitate is due to a metal substance contained in addition to the metal compound in the metal film forming composition, and adjusts the content of the metal substance to a predetermined amount. Thus, it has been found that the generation of precipitates can be suppressed, and the present invention has been completed.

The present invention relates to a metal film-forming composition comprising a water-soluble polymer and a metal compound, wherein the metal material content other than the metal compound is 50 ppm or less. Is to provide.
The present invention also provides a method for producing a metal film-forming composition comprising a water-soluble polymer and a metal compound, the method comprising producing a metal film-forming composition having a step of removing a metal substance other than the metal compound. It is to provide.
The “metal film” in the present invention is a concept including a metal film and a metal oxide film.

  According to the present invention, it is possible to suppress the generation of precipitates in the formed metal film by setting the content of the metal substance other than the metal compound contained in the metal film forming composition to 50 ppm or less. It becomes. As a result, it is possible to prevent a decrease in electrical characteristics of a device manufactured using the metal film.

The composition for forming a metal film according to the present invention includes a water-soluble polymer and a metal compound, and the content of a metal substance other than the metal compound is 50 ppm or less.
Thus, it becomes possible to suppress generation | occurrence | production of the precipitate in the metal film formed by making content of a metal substance into 50 ppm or less. Further, the content of the metal substance is more preferably 30 ppm or less.
Here, examples of the “metal substance” in the present invention include the above metal elements and silicon elements. Examples of the metal element include an alkali metal element and an alkaline earth metal element, and particularly include a sodium element and a calcium element.

In particular, in the composition for forming a metal film of the present invention, the content of the metal element is preferably 10 ppm or less, and more preferably 5 ppm or less. Among these metal elements, particularly with respect to sodium element, the content is preferably 5 ppm or less, and more preferably 1 ppm or less. By setting it as content of said range, generation | occurrence | production of the precipitate in the metal film formed can be suppressed more.
In the composition for forming a metal film of the present invention, the amount of silicon element is preferably 35 ppm or less, and more preferably 20 ppm or less. This silicon element may be contained in the surfactant described later, but by making the silicon element contained in the surfactant to be not more than the above amount, the precipitates in the formed metal film Occurrence can be suppressed.

  Hereinafter, each component in the metal film forming composition will be described.

[Water-soluble polymer]
The water-soluble polymer is not particularly limited as long as it is a water-soluble polymer that can form a metal film and can be dissolved in water at room temperature.
The water-soluble polymer is preferably purified with an ion exchange resin to remove the metal substance. Examples of the ion exchange resin include a cation exchange resin and an anion exchange resin. Among these, it is preferable to use a cation exchange resin.

  Examples of such water-soluble polymers include acrylic polymers, vinyl polymers, cellulose derivatives, alkylene glycol polymers, urea polymers, melamine polymers, epoxy polymers, amide polymers, and the like. Preferably used.

  Examples of the acrylic polymer include methyl methacrylate, N, N-dimethylacrylamide, N, N-dimethylaminopropyl methacrylamide, N, N-dimethylaminopropylacrylamide, N-methylacrylamide, diacetone acrylamide, N, Examples thereof include polymers or copolymers containing monomers such as N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, and acryloylmorpholine.

Examples of the vinyl polymer include a polymer or copolymer having a monomer such as vinyl acetate as a constituent component.
Examples of cellulose derivatives include hydroxypropylmethylcellulose phthalate, hydroxypropylmethylcellulose acetate phthalate, hydroxypropylmethylcellulose hexahydrophthalate, hydroxypropylmethylcellulose acetate succinate, hydroxypropylmethylcellulose, hydroxypropylcellulose, hydroxyethylcellulose, cellulose acetate hexahydro. Examples include phthalate, ethyl cellulose, and methyl cellulose.

  Examples of the alkylene glycol-based polymer include addition polymers or addition copolymers such as ethylene glycol and propylene glycol.

  Examples of the urea polymer include those having methylol urea, dimethylol urea, ethylene urea or the like as a constituent component.

Further, water-soluble ones such as epoxy polymers and amide polymers can be used. These can be used alone or in combination of two or more.
The water-soluble polymer preferably has a mass average molecular weight of 1,000 to 1,000,000.

Among the water-soluble polymers, it is preferable to use a cellulose derivative, and it is particularly preferable to use hydroxyalkyl cellulose among them. Cellulose derivatives have good thermal decomposability and can lower the temperature at which the composition for forming a metal film after coating is fired.
Further, when the metal film-forming composition is applied with a non-spin coater (for example, a slit nozzle coater), the water-soluble polymer (particularly the above cellulose derivative) has a viscosity at 20 ° C. of a 2% by mass aqueous solution of 1.5 mP · s. To 6.0 mP · s, more preferably 2.0 mP · s to 2.9 mP · s. By using a cellulose derivative having a viscosity of 1.5 mP · s or more, the coating property and film forming property of the metal film forming composition can be improved. Further, by using a cellulose derivative having a viscosity of 6.0 mP · s or less, it is possible to further prevent the metal film-forming composition from increasing with time.
In particular, when a non-spin coater is used as a coating apparatus, a film having a uniform film thickness cannot be formed if the viscosity is large.

[Metal compounds]
The metal compound is not particularly limited as long as it is a compound capable of forming a metal film. Examples thereof include compounds containing metals such as bismuth, rhodium, ruthenium, vanadium, chromium, tin, lead, silicon, platinum, gold, silver, copper, iron, aluminum, titanium, molybdenum, tungsten, indium, palladium, and zirconium. . Examples of these metal compounds include complexes of the above metals; formic acid, oxalic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptanoic acid, 2-ethylhexanoic acid, cyclohexane acid, cyclohexapropionic acid, cyclohexane Acetic acid, nonanoic acid, malic acid, glutamic acid, leucine acid, hydroxypivalic acid, pivalic acid, glutaric acid, adipic acid, cyclohexanedicarboxylic acid, pimelic acid, corkic acid, ethylbutyric acid, benzoic acid, phenylacetic acid, phenylpropionic acid, hydroxy Organic acid salts such as benzoic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, alginate, oleic acid, elaidic acid, linoleic acid, ricinoleic acid; nitric acid, sulfuric acid, hydrochloric acid, carbonic acid, phosphoric acid, etc. Inorganic acid salts; methoxide, ethoxide, propo Sid, butoxide alkoxide; oxide; nitride; include; hydroxides; carbides chloride, bromide, fluoride, halides such as iodides.

In the metal film forming composition according to the present invention, it is preferable to use a water-soluble compound among the above metal compounds.
Preferred examples of the metal compound include Bi (NO ₂ ) ₃ , Ti (OC ₃ H ₇ ) ₂ (C ₆ H ₁₄ O ₃ N) ₂ , ZrO (NO ₃ ) and the like.
In particular, Ti (OC ₃ H ₇ ) ₂ (C ₆ H ₁₄ O ₃ N) ₂ , Ti (C ₃ H ₅ O ₂ ) ₂ (OH) ₂ , ZrO (NO ₃ ) ₂ , ZrO (OCOCH ₃ ) ₂ or When the hydrate is used, a titanium oxide film and a zirconium oxide film can be formed. These titanium oxide films and zirconium oxide films are generally formed by a conventional sputtering method or sol-gel method. However, according to the composition for forming a metal film of the present invention, a film can be easily formed only by coating and baking, and since the storage stability is good, a sputtering method or a sol-gel method is used. More preferred.

[Organic solvent]
The composition for forming a metal film according to the present invention preferably contains an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the water-soluble polymer and the metal compound, but a water-soluble organic solvent having a boiling point of 100 ° C. or higher is preferably used.

  Examples of the organic solvent include dioxane (bp = 101 ° C.), 2,2-dimethyl-1-propanol (bp = 114 ° C.), trioxane (bp = 115 ° C.), propargyl alcohol (bp = 115 ° C.), 1- Butanol (bp = 118 ° C.), propylene glycol monomethyl ether (bp = 120 ° C.), ethylene glycol diethyl ether (bp = 121 ° C.), ethylene glycol monomethyl ether (bp = 125 ° C.), propylene glycol monoethyl ether (bp = 132) ° C), N, N-dimethylethanolamine (bp = 135 ° C.), ethylene glycol monoethyl ether (bp = 136 ° C.), N-ethylmorpholine (bp = 138 ° C.), 2-isopropoxyethanol (bp = 139 ° C.) ), Ethylene glycol monomethyl ester Teracetate (bp = 145 ° C.), methyl lactate (bp = 145 ° C.), ethylene glycol monoethyl ether acetate (bp = 145 ° C.), ethyl lactate (bp = 156 ° C.), diethylene glycol dimethyl ether (bp = 160 ° C.), 3 -Methoxy-1-butanol (bp = 160 ° C.), N, N-diethylethanolamine (bp = 162 ° C.), 2- (methoxymethoxy) ethanol (bp = 168 ° C.), diacetone alcohol (bp = 168 ° C.) 2-butoxyethanol (bp = 170 ° C.), furfuryl alcohol (bp = 170 ° C.), 3-methoxy-3-methyl-1-butanol (bp = 174 ° C.), tetrahydrofurfuryl alcohol (bp = 178 ° C.) , Ε-caprolactam (bp = 180 ° C.), 2-isopentyloxye Tanol (bp = 181 ° C.), 2,3-butanediol (bp = 181 ° C.), ethylene glycol monoacetate (bp = 182 ° C.), glycerin monoacetate (bp = 182 ° C.), diethylene glycol diethyl ether (bp = 188 ° C.) ), Propylene glycol (bp = 188 ° C.), dimethyl sulfoxide (bp = 189 ° C.), dimethyl sulfoxide (bp = 189 ° C.), dipropylene glycol monomethyl ether (bp = 190 ° C.), 1,2-butanediol (bp = 190.5 ° C.), diethylene glycol monomethyl ether (bp = 194 ° C.), tetraethylene glycol (bp = 194 ° C.), 2-methyl-2,4-pentanediol (bp = 197 ° C.), ethylene glycol (bp = 198 ° C.) ), Dipropylene glycol No ethyl ether (bp = 198 ° C.), 2,4-pentanediol (bp = 198 ° C.), diethylene glycol monoethyl ether (bp = 202 ° C.), N-methylpyrrolidone (bp = 202 ° C.), isoprene glycol (bp = 203 ° C.), 1,3-butanediol (bp = 208 ° C.), 2,2-dimethyl-1,3-propanediol (bp = 211 ° C.), 1,3-propanediol (bp = 214 ° C.), 1 , 4-butanediol (bp = 229 ° C.), diethylene glycol monobutyl ether (bp = 230 ° C.), dipropylene glycol (bp = 232 ° C.), 2-butene-1,4-diol (bp = 235 ° C.), 1, 5-pentanediol (bp = 242 ° C.), tripropylene glycol monomethyl ether (bp = 243 ° C.), etc. It is below. These may be used alone or in combination of two or more, but are not limited to the compounds listed here.

Among these, in order to improve the coating property, it is preferable to use a combination of organic solvents having a boiling point of 110 ° C. to 200 ° C. Note that an organic solvent having a boiling point of 200 ° C. or higher is inferior in drying property and takes time to form a metal pattern. Therefore, it is preferably used in combination with an organic solvent having a low boiling point rather than using alone.
In particular, when bismuth nitrate is used as the metal compound, the solvent preferably includes a glycol solvent having high solubility of bismuth nitrate. A particularly preferred glycol solvent is ethylene glycol. The glycol solvent is preferably 1% by mass to 5% by mass with respect to the total composition of the metal film forming composition.

[Surfactant]
The composition for forming a metal film according to the present invention may preferably further contain a surfactant. By containing the surfactant, the coating property can be improved.

  Examples of the surfactant include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.

  Examples of the cationic surfactant include alkyl betaine surfactants, amide betaine surfactants, sulfobetaine surfactants, hydroxysulfobetaine surfactants, amide sulfobetaine surfactants, and phosphobetaine surfactants. Surfactants, imidazolinium betaine surfactants, aminopropionic acid surfactants, amino acid surfactants and the like can be mentioned. More specifically, alkylbetaines, amidopropylbetaines, laurylhydroxysulfobetaines, lauryliminodipropionic acids and the like can be mentioned.

  Examples of the anionic surfactant include alkyl sulfonate, alkyl sulfate, acylated amino acid salt, polyoxyethylene alkyl ether sulfate, alkyl benzene sulfonate, N-acyl-N-methyl taurate, α-olefin. Examples thereof include sulfonates, higher fatty acid ester sulfonates, alkyl ether acetates, polyoxyethylene alkyl ether acetates, fatty acid soaps, and alkyl phosphate esters. The salt used here is preferably a metal salt such as sodium, potassium or magnesium; an ammonium salt; an organic ammonium salt such as monoethanolammonium, diethanolammonium or triethanolammonium salt.

  Examples of amphoteric surfactants include alanine surfactants, imidazolium betaine surfactants, amidopropyl betaine surfactants, aminodipropionate surfactants, and the like as described above for the cationic surfactants. Is mentioned.

  Nonionic surfactants include polyoxyalkylene alkyl ether, polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl fatty acid ester, polyoxyalkylene allyl phenyl ether, polyoxyalkylene sorbitan fatty acid ester, sorbitan fatty acid ester, and polyoxyalkylene. Etc.

  Among these, it is particularly preferable to use a silicon-based surfactant containing an organosilicon compound. The silicon-based surfactant is not particularly limited, and examples thereof include alkylsiloxane groups such as trade name SI-10 series (manufactured by Takemoto Yushi Co., Ltd.), MegaFac Paintad 31 (manufactured by Dainippon Ink & Chemicals, Inc.) and ethylene. A nonionic silicon-based surfactant in which an oxy group and a propyleneoxy group are bonded, such as an alkylsiloxane group, an ethyleneoxy group, and a propyleneoxy group such as trade name X-70-090 (manufactured by Shin-Etsu Chemical Co., Ltd.). It is possible to use a nonionic fluorine-containing silicon surfactant to which an ester group is bonded.

  However, the content of the silicon surfactant in the metal film forming composition is preferably 5000 ppm or less, more preferably 2000 ppm or less, and even more preferably 1500 ppm or less. Thereby, while improving applicability | paintability, it becomes possible to suppress more generation | occurrence | production of the precipitate in the surface of the metal film formed.

[Composition of metal film forming composition]
The metal film forming composition according to the present invention contains a water-soluble polymer and a metal compound as main components, and preferably contains a surfactant. Moreover, you may add a leveling agent, a coloring agent, coloring agents, such as a dye, a pigment, a filler, an adhesive imparting agent, a plasticizer as needed. In addition, there is no restriction | limiting in particular about each component, A well-known component can be used.

  The content of the metal compound is preferably 0.01% by mass to 5% by mass with respect to the total composition of the metal film forming composition in terms of the amount of metal contained in the metal compound. More preferably, the content is 1% by mass to 2% by mass. By setting the metal content to 0.01% by mass or more, a metal film can be sufficiently formed. Moreover, by making content into 5 mass% or less, while being able to improve the storage stability of the composition for metal film formation, applicability | paintability can be improved.

Moreover, it is preferable that content of a water-soluble polymer is 1 mass% to 50 mass% with respect to the whole composition of the composition for metal film formation. By setting the content to 1% by mass or more, the applicability of the metal film forming composition can be improved. Moreover, formation of a film | membrane can be made easy by content being 20 mass% or less.
In addition, content of a preferable resin component changes with the methods of apply | coating this composition part for metal film formation. For example, in the case of coating by a non-spin method, the content of the resin component is preferably 1% by mass to 10% by mass with respect to the total composition of the metal film forming composition, and 2% by mass to 6% by mass. % Is more preferable. On the other hand, when applied by a spin method, the content of the resin component is preferably 10% by mass to 50% by mass, and preferably 15% by mass to 25% by mass with respect to the total composition of the metal film forming composition. % Is more preferable.

The content of the organic solvent is not particularly limited, but is preferably 70% by mass to 98% by mass, and 85% by mass to 95% by mass with respect to the total composition of the metal film forming composition. More preferably.
The metal film-forming composition preferably has a viscosity of 1 cP to 20 cP, and more preferably 5 cP to 15 cP.

[Method for producing metal film-forming composition]
The manufacturing method of the composition for forming a metal film of the present invention includes a step of removing a metal substance other than the metal compound. The step of removing the metal substance includes a method of purifying the water-soluble polymer with an ion exchange resin, particularly preferably with a cation exchange resin. For purification of the water-soluble polymer, the metal substance may be removed up to a predetermined amount.
The composition for forming a metal film can be obtained by dissolving the purified water-soluble polymer and the metal compound in a solvent. At that time, various additives such as a surfactant, a leveling agent, a color former, and a dye can also be added.

[Method of forming metal film]
Hereinafter, a procedure for forming a metal film using the metal film forming composition of the present embodiment will be described. The metal film is obtained by firing a composition for forming a metal film applied to a substrate such as a glass plate. The firing temperature is not particularly limited as long as it is a temperature at which a metal film is formed, and is usually about 400 ° C. to 700 ° C. When a silicon wafer is used as the substrate, the metal film can also be formed by ashing the applied metal film forming composition.

  As a method for applying the metal film forming composition, a spin coater, a non-spin coater, a roll coater, a curtain flow coater, a spray coater, a dip coater, a bar coater, a table coater, or the like can be applied, and any method may be used. In particular, it is preferable to use a non-spin coater.

  The metal film obtained by such a method can be used when forming the metal wiring part of an electronic device. The metal film is preferably used for manufacturing an electron emission portion of an electron emission element display.

[Example 1]
Hydroxypropyl cellulose (trade name: HPC-SSL, manufactured by Nippon Soda Co., Ltd.), bismuth nitrate pentahydrate, propylene glycol monomethyl ether (hereinafter referred to as PGME) and ethylene glycol (hereinafter referred to as EG), silicon-based surfactant ( A product name: Granol 440 (manufactured by Kyoeisha Chemical Co., Ltd.) was mixed in the composition shown in Table 1 to obtain a metal film forming composition. In addition, the viscosity of this composition for metal film formation was about 10 cP.
The hydroxypropyl cellulose was dissolved in propylene glycol monomethyl ether and purified with a 400 cc column containing 200 cc of an ion exchange resin (trade name: Amberlite IR124, manufactured by Organo).
Further, in this metal film forming composition, the sodium element was 400 ppb and the silicon element was 19 ppm.
The amount of sodium element is measured by atomic absorption analysis (flame method, apparatus: Z-8200, manufactured by Hitachi, Ltd.), and the amount of silicon element is measured using ICP analysis (apparatus JY238Ultra, manufactured by Horiba, Ltd.). did.

[Example 2]
Hydroxypropyl cellulose (trade name: HPC-SSL, manufactured by Nippon Soda Co., Ltd.), Ti (OC ₃ H ₇ ) ₂ (C ₆ H ₁₄ O ₃ N) ₂ (trade name: Olgatics TC-400, manufactured by Matsumoto Pharmaceutical Co., Ltd.) ), PGME, propanol, and silicon-based surfactant (trade name: Granol 440, manufactured by Kyoeisha Chemical Co., Ltd.) were mixed in the composition shown in Table 1 to obtain a metal film forming composition. In addition, the viscosity of this composition for metal film formation was about 10 cP. Hydroxypropylcellulose used was purified in the same manner as in Example 1.

[Example 3]
Hydroxypropyl cellulose (HPC-SSL, manufactured by Nippon Soda Co., Ltd.), ZrO (NO ₃ ) ₂ · nH ₂ O (trade name: Zircosol ZN, manufactured by Daiichi Rare Element Chemical Industries, Ltd.), PGME and H ₂ O, silicon-based interface An activator (trade name: Granol 440, manufactured by Kyoeisha Chemical Co., Ltd.) was mixed in the composition shown in Table 1 to obtain a metal film forming composition. In addition, the viscosity of this composition for metal film formation was about 10 cP. Hydroxypropylcellulose used was purified in the same manner as in Example 1.

[Comparative Example 1]
A metal film-forming composition having the composition shown in Table 1 was produced in the same manner as in Example 1 except that hydroxypropylcellulose was used without purification.
In this metal film forming composition, the sodium element was 30 ppm and the silicon element was 38 ppm.

The metal film forming compositions of Examples and Comparative Examples were applied to a 1250 × 1100 mm glass substrate with a thickness of 1 μm using a non-spin coater (TR63, manufactured by Tokyo Ohka Kogyo Co., Ltd.), and then 15 ° C. at 500 to 600 ° C. A metal film was obtained by baking for a minute.
In addition, a metal film was similarly formed and evaluated for the above-described composition for forming a metal film spin-coated on a silicon wafer and a SiO ₂ wafer.
Then, the surface of the obtained metal film was confirmed at a magnification of 50,000 using a scanning electron microscope. As a result, the samples of Examples 1 to 3 could not confirm the generation of precipitates, whereas the sample of Comparative Example 1 was confirmed to generate the precipitates.
Thereby, it was shown that the composition for forming a metal film according to the present invention is effective in suppressing the generation of precipitates on the surface of the metal film after firing.

Claims (12)

A metal film-forming composition comprising a water-soluble polymer and a metal compound,
Content of metal substances other than the said metal compound is 50 ppm or less, The composition for metal film formation characterized by the above-mentioned.   The composition for forming a metal film according to claim 1, wherein the metal substance contains at least one of a metal element and a silicon element.   The composition for forming a metal film according to claim 2, wherein the content of the silicon element is 35 ppm or less.   The composition for forming a metal film according to claim 2 or 3, wherein the metal element is at least one selected from an alkali metal element or an alkaline earth metal element.   5. The composition for forming a metal film according to claim 2, wherein the content of the metal element is 30 ppm or less.   The composition for forming a metal film according to claim 5, wherein the metal element is a sodium element.   The composition for forming a metal film according to claim 6, wherein the content of sodium element is 5 ppm or less.   The composition for forming a metal film according to any one of claims 1 to 7, wherein the water-soluble polymer is purified by an ion exchange resin.   The composition for forming a metal film according to claim 1, wherein the water-soluble polymer contains hydroxyalkyl cellulose.   The composition for forming a metal film according to any one of claims 1 to 9, comprising a silicon-based surfactant, and the content thereof is 5000 ppm or less with respect to all solid components other than the solvent. A method for producing a metal film-forming composition comprising a water-soluble polymer and a metal compound,
The manufacturing method of the composition for metal film formation which has the process of removing metal substances other than the said metal compound. The method for producing a metal film forming composition according to claim 11, wherein the step of removing the metal substance includes a step of purifying the water-soluble polymer with an ion exchange resin.