JPH1083718A - Method for forming transparent conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To establish a method for forming a transparent conductive film which allows easy formation of fine patterns consisting of the transparent conductive film having a low electric resistivity. SOLUTION: Onto a heat resistant base board compositions for forming a transparent conductive film are applied containing an indium compound to become an oxide with the heat, a tin compound to become an oxide with the heat, a resin sensitive for radiations, and a liquid solvent, or otherwise are applied with compositions containing indium compound having a photo-reactive functional radical or portion, a tin compound having a photo-reactive functional radical or portion, and a liquid medium, and after drying and film formation, the obtained film is subjected to exposure to radiation in pattern form and development. The developed object is heated to produce a transparent conductive film, and the intended film with patterning at a low electric resistivity is formed by irradiating this with beams of light having wavelengths under 400nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a transparent conductive film and a method for forming the same, and more particularly, to a method for forming a transparent conductive film having a low resistivity in an arbitrary pattern by a coating method.

[0002]

2. Description of the Related Art Conventionally, electrodes for display elements such as a liquid crystal display element and an electroluminescence display element, and heating resistors for preventing fogging or icing of window glass of automobiles, aircraft, buildings, etc. An electrode material having high transparency to visible light is used.

Conventionally, as such a transparent conductive material, for example, a tin oxide / antimony oxide system, an indium oxide / tin oxide system (ITO), and the like are known. A transparent conductive film can be formed over a ceramic substrate. As a method for forming such a transparent conductive film, for example, a vacuum evaporation method, a sputtering method, a CVD method, and the like are known.

When a uniform transparent conductive film having a fine pattern is formed on a substrate, a flat transparent conductive film is first formed on the substrate, and a positive photosensitive film is formed on the surface of the transparent conductive film. A photosensitive resin is formed by uniformly coating and drying a conductive resin (resist) to form a photosensitive layer, exposing the photosensitive layer through a mask having a predetermined pattern, removing the resist in the exposed portion, and developing the resist. After drying, a method of forming a pattern by etching the transparent conductive film, and using a negative photosensitive resin, exposure in the same manner as above, the non-exposed portion is removed with a developer, and further dried After that, a method (photolithographic method) of forming a pattern by etching a transparent conductive film using a resist in an exposed portion as a mask is performed.

[0005]

However, in such a conventional method for forming a transparent conductive film, the film forming apparatus is complicated and expensive, and there is a problem in cost and mass productivity. Further, the method for forming the patterned electrode is a widely used method, but has a problem that the steps of coating, drying, exposing, developing, drying, and etching the resist itself are complicated.

As a method for solving these problems, various coating methods using a so-called sol-gel method have been proposed.
The quality of the transparent conductive film formed by this coating method is not yet sufficient. Furthermore, a method of printing a coating liquid containing a component for forming a transparent conductive film in a pattern by a printing method and then performing a heat treatment may be considered. In this method, a fine pattern of a micron unit or a submicron unit is formed. Is difficult, and the formed fine pattern is not completely satisfactory in terms of accuracy. Also,
There is also a problem that the formed transparent conductive film has a high electric resistivity and cannot be used as an electrode of a display element in terms of conductivity.

The present invention has been made in view of the above circumstances, and provides a method of forming a transparent conductive film that can easily form a fine pattern made of a transparent conductive film having a low electric resistivity. The purpose is to:

[0008]

In order to achieve such an object, a method for forming a transparent conductive film according to a first aspect of the present invention comprises an indium compound which becomes an oxide by heating, and a tin compound which becomes an oxide by heating. A radiation-sensitive resin, and
A step of applying a composition for forming a transparent conductive film containing a liquid medium on a heat-resistant substrate and drying and forming a film, a step of developing the formed film by radiation exposure in a pattern, and a heat treatment of the developed product And a step of irradiating the transparent conductive film formed by the heat treatment with light having a wavelength of 400 nm or less.

The method for forming a transparent conductive film according to the second invention is directed to an indium compound having a functional group or site that reacts with light, a tin compound having a functional group or site that reacts with light, and a liquid. A step of applying a composition for forming a transparent conductive film containing a medium on a heat-resistant substrate and drying and forming a film; a step of subjecting the formed film to radiation exposure and developing in a pattern; A process of forming a conductive film,
And a wavelength of 400 for the transparent conductive film formed by the heat treatment.
It was configured to include a step of irradiating light of nm or less.

The composition for forming a transparent conductive film further contains a thermally decomposable resin binder.

In the present invention as described above, a film formed of a composition for forming a transparent conductive film formed by coating on a heat-resistant substrate is exposed to radiation in a pattern and the exposed or unexposed portions are removed and developed. Thereby, patterning is easily performed, and thereafter, a heat treatment is performed to form a transparent conductive film.
By irradiating light having a wavelength of 400 nm or less, the resistance of the transparent conductive film is reduced.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to embodiments of the present invention.

The method for forming a transparent conductive film according to the first invention comprises a step of applying a composition for forming a transparent conductive film on a heat-resistant substrate, drying the film, and exposing the formed film to radiation in a pattern. The method includes a step of developing, a step of heat-treating the developed product to form a transparent conductive film, and a step of irradiating the transparent conductive film formed by the heat treatment with light having a wavelength of 400 nm or less.

The composition for forming a transparent conductive film used in the first invention is a transparent composition containing an indium compound which becomes an oxide by heating, a tin compound which becomes an oxide by heating, a radiation-sensitive resin, and a liquid medium. This is a composition for forming a conductive film.

The indium compound which becomes an oxide by heating which constitutes the composition for forming a transparent conductive film includes:
For example, organic or inorganic salts of indium such as indium formate, indium acetate, indium oxalate, indium nitrate, indium chloride, indium sulfate, and
Hydrates, indium methoxide, indium ethoxide, indium propoxide, indium alkoxides such as indium butoxide, and these compounds, and α- or β-diketones, α- or β-ketone acids, and the above ketones Esters of acids, α- or β
-Chelated products with amino alcohols and the like.

Examples of the tin compound which becomes an oxide by heating in the composition for forming a transparent conductive film include tin formate, tin acetate, tin oxalate, tin nitrate, tin chloride, and the like.
Tin bromide, tin fluoride, tin organic or inorganic salts such as tin iodide, and hydrates thereof, tin methoxide, tin ethoxide, tin propoxide, tin alkoxide such as tin butoxide, and these Chelated products of compounds with α- or β-diketones, α- or β-ketone acids, esters of the above ketone acids, α- or β-amino alcohols, and the like.

As the composition for forming a transparent conductive film used in the present invention, in addition to the above-mentioned compounds having a clear boundary between indium and tin, those comprising a cluster and an inorganic polymer can also be used. . Further, a hydrolysis product generated by an acid or a base or a product generated by hydrothermal synthesis using the above-mentioned indium compound or tin compound as a raw material, synthesized ITO particles, and the like can also be used. Such an I
The particle size of the TO precursor is preferably at least 1 μm or less in view of reactivity and uniformity of a finally obtained film.

The ratio of the above-mentioned indium compound and tin compound is based on the atomic ratio of indium to tin.
It is preferable to use tin in a ratio of 0.01 to 0.20 atom per atom. If the amount of tin used is insufficient, the carrier density will be low and the conductivity will be deteriorated, which is insufficient.On the other hand, if the amount of tin used is too large, the carrier mobility will decrease and the conductivity will deteriorate. It is not enough in terms of doing.

The radiation-sensitive resin constituting the composition for forming a transparent conductive film is a conventional positive or negative photosensitive resin, for example, polymethyl vinyl ketone, polyvinyl phenyl ketone, polysulfone. , P
Diazonium salts, such as diazodiphenylamine / paraformaldehyde polycondensates, 1,2-naphthoquinone-2
And known positive resists such as quinonediazides such as -diazide-5-sulfonic acid isobutyl ester, polymethyl methacrylate, polyphenylmethylsilane, and polymethylisopropenyl ketone. In addition, glue,
Casein, shellac, polyvinyl alcohol, etc. mixed with ammonium dichromate, mixed system of polyvinyl alcohol and diazo resin, polyvinyl cinnamate, cyclized rubber-azide, (meth) acrylic monomer or (meth) acrylic Resin systems containing the oligomer alone or both are included. These photosensitive resins impart photosensitivity to the composition for forming a transparent conductive film, and also function as a binder for the obtained composition (coating liquid), and have an action of giving coating suitability to the coating liquid. .

The photosensitive resin is used in an amount of 10 to 10 parts by weight of the total amount of the indium compound and the tin compound.
Preferably, it is used in a proportion of 1000 parts by weight. If the amount of the photosensitive resin used is insufficient, the pattern cannot be formed, which is insufficient. On the other hand, if the amount of the photosensitive resin is too large, the transparent conductive film (ITO film) obtained by firing after patterning is used. ) Is inadequate in that the film quality deteriorates and desired electrical characteristics cannot be obtained.

The composition for forming a transparent conductive film is prepared by dissolving or dispersing the above-mentioned components in a liquid medium. Examples of the liquid medium include water, an organic solvent, and a mixture thereof. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol, and butanol, ethyl acetate, acetates such as butyl acetate, acetone, and methyl ethyl ketone. , Diethyl ketone, ketones such as acetylacetone, methoxyethanol, ethers such as ethoxyethanol, hetero compounds such as dioxane and tetrahydrofuran, sulfur compounds such as dimethyl sulfoxide, and amines such as ethanolamine, diethanolamine and triethanolamine. And amide compounds such as N, N-dimethylformamide, and aromatics such as toluene and xylene. The type and composition of the liquid medium can be appropriately selected according to the type of the indium compound, tin compound, and photosensitive resin used. For example, when the indium compound and tin compound used are salts of these metals, and the photosensitive resin is a water-soluble resin, water or a mixture of water and an organic solvent is used as a liquid medium, if necessary. It is preferable to neutralize the salts to convert the metal salt into a hydroxide. On the other hand, when the indium compound or tin compound used is an organic metal compound such as an alkoxide, and the photosensitive resin is an organic solvent-soluble resin, an organic solvent or a mixture of an organic solvent and water is used as a liquid medium. Preferably, the organometallic compound is hydrolyzed to form a hydroxide, if necessary. As described above, when neutralization or hydrolysis is performed, the metal component is in a state of hydroxide or oxide, and becomes a dispersion liquid (sol or colloid) of fine particles.

The amount of the above-mentioned liquid medium can be appropriately set depending on the types of the indium compound, tin compound and photosensitive resin used. Generally, the solid content of each component is 1 to 30% by weight. Is preferably used in such an amount that the above ratio is obtained. If the amount of the liquid medium is insufficient, the coatability of the coating film is insufficient, for example, and the coating film is insufficient.If the amount of the liquid medium is too large, the transparent conductive film obtained by firing the coating film is insufficient. (I
This is insufficient in that the thickness of the (TO film) becomes thin, and defects in the coating film tend to occur.

The composition for forming a transparent conductive film is made of ITO
A composition containing a precursor and a radiation-sensitive resin, which can be easily obtained by simply mixing each component, and may be subjected to neutralization or hydrolysis treatment as necessary after preparation of the composition. Good. Further, an additive such as a sensitizer may be contained as needed. Such a composition for forming a transparent conductive film may be prepared in a concentrated state, added with a liquid medium immediately before use to impart coating suitability, and then used. In addition, it is desirable to store in a cool and dark place.

Examples of the heat-resistant substrate used in the first invention include a heat-resistant substrate such as glass and ceramic. Examples of the application include a liquid crystal display element, a plasma display, an electromagnetic wave shield, an antistatic, and an ultraviolet ray. cut,
And materials for heat ray cutting.

As a method of applying the composition for forming a transparent conductive film to the above substrate, known coating methods such as a screen printing method, a roll coating method, a dip coating method, a spin coating method, a die coating method, and a bead coating method are used. Can be used. The coating amount varies depending on the use of the electrode substrate to be formed, but is generally about 0.1 to 100 μm as a solid coating amount. Drying conditions after coating are arbitrary, but are usually at a temperature that does not adversely affect the photosensitive resin constituting the composition for forming a transparent conductive film, for example, at about 80 to 200 ° C. for about 0.1 to 1 hour.

The coating thus formed is almost electrically insulating. Next, a photomask having a desired fine pattern is brought into close contact with the coating film thus formed and exposed. The radiation used for exposure is usually
The light has a wavelength of about 200 to 500 nm. For example, a high-pressure mercury lamp or the like can be used as a light source. This exposure decomposes, denatures, or cures the exposed portion of the photosensitive resin, and the exposed or unexposed portion of the coating loses solubility in the developing solution or deteriorates adhesion to the substrate. Alternatively, the exposed substrate or the unexposed portion is peeled off by immersing the exposed substrate in a developing solution and rubbing (brushing) the surface as necessary, thereby forming an image.

Next, the above image is subjected to a heat treatment. By this heat treatment, the photosensitive resin remaining in the coating is decomposed and vaporized, while the indium compound and the tin compound are converted into a composite oxide (ITO), and the pattern coating is given transparency and conductivity. Preferred heating conditions for such treatment are about 300 to 600 ° C. and about 0.1 to
2.0 hours. Heating conditions that are too mild are insufficient in that thermal decomposition and crystallization do not proceed sufficiently, while heating conditions that are too severe have a large effect on the substrate, and the oxidation of ITO itself is more than necessary. This is not preferable in that it becomes insufficient to secure oxygen deficiencies necessary for developing conductivity.

Next, a wavelength of 400 nm or less, preferably 150 to 400 nm, is applied to the transparent conductive film heat-treated as described above.
Irradiate light of nm. The wavelength of the irradiated light is 400 nm
In the visible light range from over 700 nm to 700 nm, most of the light passes through the transparent conductive film, and if it exceeds 700 nm, there is a wavelength to be absorbed, but the energy of light is small, so that the density of conduction electrons in the transparent conductive film cannot be increased. However, the effects of the present invention cannot be achieved. Further, the wavelength of the irradiated light is 15
If it is less than 0 nm, it will be in the vacuum ultraviolet region, and will not have industrial utility value. As a light source for such light irradiation,
Light source using ultra high pressure, high pressure, medium pressure, low pressure metal vapor gas, rare gas, hydrogen, Xe ₂ , Kr-Cl, Xe-Cl, for example, light source such as high pressure mercury lamp, excimer lamp, or excimer laser , a dye laser, Ar ion laser, a laser F ₂ laser or the like can be used. More specifically, a Hg-Xe ultraviolet lamp (main peak of wavelength = 360 nm), a low-pressure Hg lamp (main peak of wavelength = 254 nm), a Kr-Cl excimer lamp (main peak of wavelength = 222 nm), or
Xe-Cl (308 nm), Xe-F (351 nm),
Xe-Br (282 nm), Kr-F (249 nm),
Excimer laser such as Kr-Cl (222 nm), Ar
Ion laser second harmonic (257.2 nm), dye laser second harmonic crystal (β-BaB ₂ · BO ₄ , 205
nm), it may be mentioned F ₂ laser (157 nm) or the like.

The irradiation energy in the light irradiation is a condition such as increasing the density of the conduction electrons in the transparent conductive film and lowering the electric resistivity, such as connection of the respective particles in the transparent conductive film. It can be appropriately set according to the transparent conductive film material to be used, the thickness of the transparent conductive film, the light source used, the purpose of use of the transparent conductive film, and the like.

Through the above steps, a transparent conductive film (ITO) having a pattern exactly matching the pattern of the photomask is formed.
A film is formed on a substrate, and this ITO film has excellent transparency and conductivity as well as an ITO film formed by a conventional vacuum deposition method, sputtering method, or CVD method. Therefore, according to the present invention, a transparent conductive film having a pattern useful for various uses can be formed by a simple process without using an expensive device.

Next, a method for forming a transparent conductive film according to the second invention will be described. This method for forming a transparent conductive film includes a step of applying a composition for forming a transparent conductive film on a heat-resistant substrate, drying and forming a film, a step of subjecting the formed film to radiation exposure in a pattern, and developing the resultant. A step of heating to form a transparent conductive film, and a step of applying a wavelength of 4 to the transparent conductive film formed by the heat treatment.
The method includes a step of irradiating light of 00 nm or less.

The composition for forming a transparent conductive film used in the second invention comprises an indium compound having a functional group or site reactive to light, a tin compound having a functional group or site reactive to light, and a liquid. A composition for forming a transparent conductive film containing a medium.

Examples of the indium compound having a functional group which reacts to light which constitutes the composition for forming a transparent conductive film include indium formate, indium acetate, indium oxalate, indium nitrate, indium chloride, indium sulfate and the like. Organic or inorganic salts of indium, indium methoxide, indium ethoxide, indium propoxide, indium alkoxide such as indium butoxide, and the like, obtained by reacting these compounds with an organic substance that forms a chelate (chelate-forming compound). Compounds.

Examples of the tin compound having a functional group which reacts to light which constitutes the composition for forming a transparent conductive film include tin alkoxides such as tin methoxide, tin ethoxide, tin propoxide and tin butoxide. With an organic substance (chelate-forming compound) which forms a chelate with these compounds.

The organic substance (chelate-forming compound) used for producing the above-mentioned indium compound having a functional group that reacts with light and the tin compound having a functional group that reacts with light include indium or tin and a chelate. An organic substance that forms and is released by light, for example, acetylacetone, benzoyltrifluoroacetone, pivaloyltrifluoroacetone, methyl acetoacetate, ethyl acetoacetate, phenolacetoacetate, benzoic acid, naphthol,
Naphthoic acid and the like.

The reaction of the above-mentioned indium compound or tin compound with the above-mentioned organic substance (chelate-forming compound) is carried out, for example, when alkoxide is used as the indium compound and acetylacetone is used as the chelate compound.

In (OR) _n + XCH ₃ COCH ₂ C
OCH ₃ → In (OR) _nx [OC (CH ₃ ) = CHC
OCH ₃ ] _x + XROH (R is an alkyl group of an alkoxide group, and n is a valence of indium) As the indium compound and the tin compound having a functional property to react with light, at least one bond of a metal atom The hand only needs to be bonded to a functional group that reacts to light, and the other bond may be in a salt state. Further, in addition to the above composition, those in which an indium compound or a tin compound forms a polymer complex with a photosensitive polymer are also included. Examples of the photosensitive polymer include photosensitive polymers such as poly (meth) acrylate and polyvinyl alcohol.

Further, examples of the indium compound and tin compound having a site that reacts to light include substances having absorption at a wavelength of 400 nm or less. For example, the above-mentioned indium compound or tin compound is used as a raw material, and it is a hydrolysis product generated by an acid or a base, a product generated by hydrothermal synthesis, a cluster of synthesized ITO particles, or an inorganic polymer. Such an ITO precursor preferably has a particle size of at least 1 μm or less in view of reactivity and uniformity of a finally obtained film.

The ratio of the indium compound to the tin compound is such that the atomic ratio of indium to tin is indium 1
It is preferable to use tin in a ratio of 0.01 to 0.20 atom per atom. If the amount of tin used is insufficient, the carrier density will be low and the conductivity will be deteriorated, which is insufficient.On the other hand, if the amount of tin used is too large, the carrier mobility will decrease and the conductivity will deteriorate. It is not enough in terms of doing.

The composition for forming a transparent conductive film is prepared by dissolving or dispersing the above-mentioned components in a liquid medium. Examples of the liquid medium include water, an organic solvent, and a mixture thereof. As the organic solvent, the organic solvents described in the description of the composition for forming a transparent conductive film in the first invention can be used. .

Regarding the type and composition of the liquid medium,
It can be appropriately selected according to the type of the indium compound and the tin compound to be used. For example, when the indium compound and tin compound having a functional group or site that reacts to light to be used are water-soluble or hydrophilic, such as in the case of partially having a salt form, they are used as a liquid medium. Water or a mixture of water and an organic solvent may be used, and if necessary, the salt portion may be neutralized to form a hydroxyl group. On the other hand, when the indium compound and tin compound having a functional group or site that reacts to light used are highly organic and soluble in an organic solvent, the organic solvent or the organic solvent and water are used as a liquid medium. It is preferred to use a mixture.

The amount of the liquid medium to be used can be appropriately set depending on the type of the indium compound and the tin compound used. Generally, the solid content of each component is 1 to 20% by weight.
Is preferably used in such an amount that the above ratio is obtained. If the amount of the liquid medium is insufficient, the coatability of the coating film is reduced, and the formed coating film is insufficient in that cloudiness and cracks occur, while the amount of the liquid medium is too large. In addition, the film thickness of ITO obtained by baking the coating film becomes thin, and the coating film is likely to have defects, and it is insufficient in that it is difficult to obtain a desired conductivity.

Further, the composition for forming a transparent conductive film described above comprises:
For the purpose of improving coatability, a thermally decomposable resin binder may be contained. Examples of such a resin binder include methyl cellulose, ethyl cellulose, acetyl cellulose, acetyl ethyl cellulose, hydroxypropyl cellulose, benzyl cellulose, nitrocellulose, and the like. Further, a photosensitive polymer and a conventional photoresist may be mixed for the purpose of broadening the photosensitive wavelength range. The amount of the resin binder used is 1 to 100 parts by weight of the total of the indium compound and the tin compound.
A ratio of 0 to 1000 parts by weight is preferred. If the amount of the resin binder used is insufficient, it is insufficient in terms of coatability and the like,
On the other hand, if the amount of the resin binder used is too large, the film quality of the ITO film obtained by baking after patterning deteriorates and is insufficient in that desired electrical characteristics cannot be obtained.

The composition for forming a transparent conductive film is made of ITO
The composition contains, as a precursor, an indium compound and a tin compound having a functional group or site which is released, decomposed, modified or transferred by light. Further, an additive such as a sensitizer may be contained as needed. Such a composition for forming a transparent conductive film may be prepared in a concentrated state, added with a liquid medium immediately before use to impart coating suitability, and then used. In addition, it is desirable to store in a cool and dark place.

The heat-resistant substrate used in the second invention includes the heat-resistant substrate mentioned in the first invention.

The composition for forming a transparent conductive film is applied to the above substrate to form a film. In this case, the coating method, the coating amount, and the drying conditions can be the same as those in the first embodiment.

The coating formed on the heat-resistant substrate thus formed is almost insulating. Next, a photomask having a desired fine pattern is brought into close contact with the coating and exposed. The radiation used for exposure is generally light having a wavelength of about 200 to 500 nm, and for example, a high-pressure mercury lamp or the like can be used as a light source. With this exposure, a functional group or site that reacts with light is detached, denatured, transferred, or the like, and a change in physical properties occurs. Thereby, portions having different solubility in the developing solution are formed, and a pattern corresponding to exposure can be formed. Changes in physical properties include adhesion, denseness, hydrophilicity, hydrophobicity, coating structure, crystallinity, and the like.

Next, the above image is subjected to a heat treatment. This heat treatment decomposes and vaporizes the light-reactive functional groups and binder resin (if present) remaining in the coating, while the indium compound and tin compound become complex oxides (ITO), and form a patterned oxide. Transparency and conductivity are imparted to the coating. Preferred heating conditions for such a treatment are at about 300 to 600 ° C. for about 0.1 to 2.0.
Time. Heating conditions that are too mild are insufficient in that thermal decomposition and crystallization do not proceed sufficiently, while heating conditions that are too severe have a large effect on the substrate, and the oxidation of ITO itself is more than necessary. This is not preferable in that it becomes insufficient to secure oxygen deficiencies necessary for developing conductivity.

Next, a wavelength of 400 nm or less, preferably 150 to 400 nm, is applied to the transparent conductive film heat-treated as described above.
Irradiate light of nm. The light source of such light irradiation and the irradiation energy are the same as in the first embodiment described above, and a description thereof will be omitted.

Through the above steps, a transparent conductive film (ITO film) having a pattern exactly corresponding to the pattern of the photomask in a positive-negative relationship is formed on the substrate. It is excellent in transparency and conductivity as in the case of the ITO film formed by sputtering, sputtering or CVD. Therefore, according to the present invention, it is possible to form a patterned transparent conductive film useful for various applications by a simple process without using an expensive film forming apparatus and without requiring a complicated process. It becomes possible.

[0051]

Next, the present invention will be described more specifically with reference to examples. (Example 1) (1) Preparation of composition A for forming a transparent conductive film 0.072 mol of tri-tret-butoxyindium was dissolved in 300 g of sec-butanol.
was diluted with 30 g of sec-butanol and refluxed at 100 ° C. for 1 hour.

Next, after cooling to 60 ° C., 350 g of N, N-dimethylformamide was added and
Reflux for minutes.

Next, after cooling to 60 ° C., a solution prepared by dissolving 0.04 mol of triethanolamine in 30 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

After cooling to 40 ° C., 150 g of sec-butanol was added to 0.008 m of tetra-n-butoxytin.
ol was added and refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., a solution prepared by diluting 0.08 mol of 0.1N hydrochloric acid with 150 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., the mixture was concentrated at 70 ° C. to obtain a composition having a solid content of 20% by weight.

Next, 4.48 g of diethanolamine and 19.6 g of cyclohexanol were added to the composition, and 32.7 g of a positive photoresist (NPR9100 manufactured by Nagase Electronic Chemical Co., Ltd.) was added to the composition to form a transparent conductive film. A composition A for forming was obtained. (2) Preparation of transparent conductive film (samples 1 to 14) The composition A for forming a transparent conductive film prepared in (1) above was used as a glass substrate (soda lime glass manufactured by Central Glass Co., Ltd.).
Apply evenly by spin coating on top
Dry for 0 minutes. Next, this coating is irradiated with ultraviolet rays (a main peak wavelength of 405 nm) through a photomask,
Thereafter, development was performed by immersion in a 0.5% potassium hydroxide solution. After the development was completed, the patterned glass substrate was subjected to heat treatment at 580 ° C. for 30 minutes to obtain a fine pattern of a transparent conductive film made of indium tin oxide (ITO).

Next, X was added to the fine pattern of each transparent conductive film.
An e-Cl excimer laser (wavelength 308 nm) was irradiated under the conditions shown in Table 1 below to obtain a transparent conductive film (samples 1 to 3).
14) was produced. For this transparent conductive film (samples 1 to 14), the electric resistance before and after light irradiation was measured by a four-probe method, and the results are shown in Table 1 below.

[0059]

[Table 1] As shown in Table 1, after forming a transparent conductive film by heat treatment, Samples 1 to 14 which were irradiated with light having a wavelength of 400 nm or less (Xe-Cl excimer laser irradiation) were all subjected to electrical resistivity by light irradiation. And it was confirmed that the film was a transparent conductive film having excellent conductivity. In the measurement by X-ray diffraction, the peak intensity of the (222) plane before and after the laser irradiation was a maximum of 2.25 times (12600 cps versus 5600 cps), confirming that the crystallinity of the film was improved. Was done.

On the other hand, when light irradiation is performed using light (He-Ne laser (wavelength: 633 nm)) having a wavelength exceeding 400 nm, the electrical resistivity slightly decreases,
It was inferior in practicality as a transparent conductive film. (Example 2) (1) Preparation of composition B for forming a transparent conductive film 0.139 mol of tri-tret-butoxyindium was dissolved in 500 g of sec-butanol, and 0.75 of acetic acid was added thereto.
The solution was diluted with 50 g of sec-butanol and refluxed at 100 ° C. for 1 hour.

Then, after cooling to 60 ° C., 500 g of N, N-dimethylformamide was added and
Reflux for minutes.

Next, after cooling to 60 ° C., a solution prepared by dissolving 0.1125 mol of triethanolamine in 50 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., tetra-sec-butoxy tin 0.0112 was added to 50 g of sec-butanol.
A solution in which 5 mol was dissolved was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

After cooling to 40 ° C., 0.15 mol of 0.1N hydrochloric acid diluted with 150 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., the mixture was concentrated at 70 ° C. to obtain a composition having a solid content of 20% by weight.

Next, 8.4 g of diethanolamine and 36.75 g of cyclohexanol were added to this composition, and 61.2 g of a positive photoresist (NPR9100 manufactured by Nagase Electronic Chemical Co., Ltd.) was added to the composition to form a transparent conductive film. A forming composition B was obtained. (2) Preparation of Transparent Conductive Film Same as Example 1, except that the composition B for forming a transparent conductive film prepared in the above (1) was used, and was made of heat-treated indium tin oxide (ITO). A fine pattern of a transparent conductive film was produced. Then, the fine pattern of each transparent conductive film was irradiated with a Xe-Cl excimer laser (wavelength: 308 nm) in the same manner as in Example 1, and the electric resistance before and after the irradiation was measured by a four-probe method. As a result, similarly to the fine pattern (samples 1 to 14) of the transparent conductive film of Example 1, after forming the transparent conductive film by heat treatment, the wavelength of 400 nm was obtained.
By performing the following light irradiation (Xe-Cl excimer laser irradiation), it was confirmed that any of the transparent conductive films had low electric resistivity.

As a comparison, a He—Ne laser (wavelength 633 nm) was used instead of the Xe—Cl excimer laser.
Except for using m), a fine pattern of the transparent conductive film was prepared in the same manner as in the formation of the fine pattern of the transparent conductive film, and the electric resistance before and after irradiation was measured by the four-point probe method as in Example 1. As a result of the measurement, the decrease in electrical resistivity was slight,
It was inferior in practicality as a transparent conductive film. (Example 3) (1) Preparation of composition C for forming a transparent conductive film Indium acetate was added to 1000 g of sec-butanol in 0.1 g of indium acetate.
After dissolving 216 mol, 1000 g of N, N-dimethylformamide was added thereto, and the mixture was refluxed at 120 ° C. for 1 hour.

Next, after cooling to 60 ° C., a solution prepared by dissolving 0.108 mol of triethanolamine in 100 g of sec-butanol was added, and the mixture was refluxed at 120 ° C. for 8 hours.

Then, after cooling to 40 ° C., 200 g of sec-butanol was added to 0.0 g of tri-tret-butoxyindium.
A solution prepared by dissolving 72 mol was added,
Reflux for minutes.

After cooling to room temperature, 0.023 mol of tetraethoxytin diluted with 500 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Next, after cooling to room temperature, a solution prepared by diluting 0.311 mol of 0.1N hydrochloric acid with 500 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., the mixture was concentrated at 70 ° C. to obtain a composition having a solid content of 15% by weight.

Next, a positive photoresist (NPR9100 manufactured by Nagase Electronic Chemical Co., Ltd.) was added to this composition.
By adding 45 g, a composition C for forming a transparent conductive film was obtained. (2) Preparation of Transparent Conductive Film Same as Example 1, except that the composition C for forming a transparent conductive film prepared in (1) above was used, and was made of indium tin oxide (ITO) subjected to a heat treatment. A fine pattern of a transparent conductive film was produced. Then, the fine pattern of each transparent conductive film was irradiated with a Xe-Cl excimer laser (wavelength: 308 nm) in the same manner as in Example 1, and the electric resistance before and after the irradiation was measured by a four-probe method. As a result, similarly to the fine pattern (samples 1 to 14) of the transparent conductive film of Example 1, after forming the transparent conductive film by heat treatment, the wavelength of 400 nm was obtained.
By performing the following light irradiation (Xe-Cl excimer laser irradiation), it was confirmed that any of the transparent conductive films had low electric resistivity.

As a comparison, a He—Ne laser (wavelength 633 nm) was used instead of the Xe—Cl excimer laser.
Except for using m), a fine pattern of the transparent conductive film was prepared in the same manner as in the formation of the fine pattern of the transparent conductive film, and the electric resistance before and after irradiation was measured by the four-point probe method as in Example 1. As a result of the measurement, the decrease in electrical resistivity was slight,
It was inferior in practicality as a transparent conductive film. (Example 4) (1) Preparation of composition D for forming a transparent conductive film 0.0075 mol of tetra-n-butoxytin was added to N, N
-75 g of dimethylformamide in 75 g of sec-butanol
(Solution 1).

Next, 0.0675 mol of tri-tret-butoxyindium was added to a solution of 75 g of N, N-dimethylformamide diluted with 75 g of sec-butanol (solution 2).

Solution 2 was added to Solution 1, and 0.075 mol of acetylacetone was further added to 600 g of sec-butanol.
Was added and the mixture was refluxed at 110 ° C. for 30 minutes.

Next, after cooling to room temperature, a solution prepared by diluting 0.075 mol of 0.1N hydrochloric acid with 600 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., the mixture was concentrated at 70 ° C. to obtain a composition having a solid content of 3.5% by weight.

Next, a positive photoresist (NPR9100 manufactured by Nagase Electronic Chemical Co., Ltd.) was added to this composition for 30.5 hours.
By adding 8 g, a composition D for forming a transparent conductive film was obtained. (2) other using a transparent conductive film-forming composition D prepared in Preparation the transparent conductive film (1), the same procedure as in Example 1, consisting of indium tin oxide (ITO) which has been subjected to heat treatment A fine pattern of a transparent conductive film was produced. Then, the fine pattern of each transparent conductive film was irradiated with a Xe-Cl excimer laser (wavelength: 308 nm) in the same manner as in Example 1, and the electric resistance before and after the irradiation was measured by a four-probe method. As a result, similarly to the fine pattern (samples 1 to 14) of the transparent conductive film of Example 1, after forming the transparent conductive film by heat treatment, the wavelength of 400 nm was obtained.
By performing the following light irradiation (Xe-Cl excimer laser irradiation), it was confirmed that any of the transparent conductive films had low electric resistivity.

For comparison, a He—Ne laser (wavelength 633 nm) was used instead of the Xe—Cl excimer laser.
Except for using m), a fine pattern of the transparent conductive film was prepared in the same manner as in the formation of the fine pattern of the transparent conductive film, and the electric resistance before and after irradiation was measured by the four-point probe method as in Example 1. As a result of the measurement, the decrease in electrical resistivity was slight,
It was inferior in practicality as a transparent conductive film. (Example 5) (1) Preparation of composition E for forming a transparent conductive film 0.008 mol of tetra-sec-butoxy tin was added to N, N-
50 g of dimethylformamide in 500 g of sec-butanol
(Solution 1).

Next, 0.072 mol of tri-tret-butoxyindium was added to N, N-dimethylformamide 5
0 g was added to a solution diluted with 500 g of sec-butanol (solution 2).

Solution 2 was added to Solution 1, and a solution obtained by diluting 0.24 mol of benzoyltrifluoroacetone with 500 g of sec-butanol was added.
Reflux for minutes.

After cooling to room temperature, 0.08 mol of 0.1N hydrochloric acid diluted with 500 g of sec-butanol was added, and the mixture was refluxed at 110 ° C. for 30 minutes.

Then, after cooling to 40 ° C., the mixture was concentrated at 70 ° C. to obtain a composition E for forming a transparent conductive film having a solid content of 5.0% by weight. (2) Preparation of transparent conductive film (samples 15 to 18) The composition E for forming a transparent conductive film prepared in (1) above was used as a glass substrate (Soda-lime glass manufactured by Central Glass Co., Ltd.).
Apply evenly by spin coating on top
Dry for 0 minutes. Next, the film is irradiated with ultraviolet rays (main peak wavelength: 365 nm) through a photomask,
Thereafter, the film was immersed in a hydrochloric acid solution of pH 2 to perform development.
After the development is completed, the patterned glass substrate is
For 30 minutes to obtain a fine pattern of a transparent conductive film made of indium tin oxide (ITO).

Next, X was added to the fine pattern of each transparent conductive film.
The transparent conductive film (sample 15) was irradiated with an e-Cl excimer laser (wavelength 308 nm) under the conditions shown in Table 2 below.
To 18). This transparent conductive film (samples 15 to 1)
Regarding 8), the electric resistance before and after light irradiation was measured by the four probe method, and the results are shown in Table 2 below.

[0086]

[Table 2] As shown in Table 2, after forming a transparent conductive film by heat treatment, Samples 15 to 18 which were irradiated with light having a wavelength of 400 nm or less (Xe-Cl excimer laser irradiation) were all subjected to electrical resistivity by light irradiation. And it was confirmed that the film was a transparent conductive film having excellent conductivity.

On the other hand, when light irradiation is performed using light (He-Ne laser) having a wavelength exceeding 400 nm,
The decrease in the electrical resistivity was slight, and was inferior in practical use as a transparent conductive film.

[0088]

As described in detail above, according to the present invention, an indium compound which becomes an oxide by heating, a tin compound which becomes an oxide by heating, a radiation-sensitive resin, and a liquid medium are formed on a heat-resistant substrate. And a transparent conductive film comprising a composition for forming a transparent conductive film, or an indium compound having a functional group or site reactive to light, a tin compound having a functional group or site reactive to light, and a liquid medium. After coating the film-forming composition and drying to form a film, the film is exposed to radiation in a pattern and developed, and then the developer is heat-treated to form a transparent conductive film. By irradiating the following light, an expensive film forming apparatus and complicated steps are not required, and a fine pattern made of a transparent conductive film can be formed in a simple step, and
The formed transparent conductive film becomes a transparent conductive film having low resistivity.

Claims (3)

[Claims] 1. A composition for forming a transparent conductive film, comprising an indium compound that becomes an oxide when heated, a tin compound that becomes an oxide when heated, a radiation-sensitive resin, and a liquid medium, are coated on a heat-resistant substrate. And a step of drying and forming a film, a step of developing the formed film by radiation exposure in a pattern,
A step of heating the developer to form a transparent conductive film, and
A method for forming a transparent conductive film, comprising a step of irradiating light having a wavelength of 400 nm or less to the transparent conductive film formed by the heat treatment. 2. A composition for forming a transparent conductive film, comprising: an indium compound having a functional group or site reactive to light; a tin compound having a functional group or site reactive to light; and a liquid medium. Coating on a substrate, drying and forming a film, radiation-exposing the formed film to a pattern and developing, heating the developed product to form a transparent conductive film, and heating. Wavelength 4 for transparent conductive film
A method for forming a transparent conductive film, comprising a step of irradiating light having a thickness of 00 nm or less. 3. The method for forming a transparent conductive film according to claim 2, wherein the composition for forming a transparent conductive film further contains a thermally decomposable resin binder.