KR100611538B1 - A solution for forming a transparent conductive film and a process for forming a transparent conductive film on a substrate using the solution - Google Patents

Abstract

(Problem) Provided is a transparent conductive film forming solution capable of forming a very uniform transparent conductive film at sheet resistance and transparency, and a method for producing a substrate with a transparent conductive film having a transparent conductive film having a very uniform sheet resistance and transparency.

Solution: Equation [1]

In (R ¹ COCHCOR ² ) ₃ [1]

(In formula, R <^1> and R <^2> respectively independently represents a C1-C10 alkyl group or a phenyl group.), And the indium compound represented by Formula [2]

(R ³ ) ₂ Sn (OR ⁴ ) ₂ [2]

In the formula, R ³ represents an alkyl group having 1 to 10 carbon atoms, R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms, and optionally the formula [1] Of a transparent conductive film forming liquid, and a substrate with a transparent conductive film using such a transparent conductive film forming liquid, comprising a β-diketone compound that dissolves an indium compound represented by the formula and a tin compound represented by the formula [2]. It is a manufacturing method.

Description

A transparent conductive film forming liquid and a method for manufacturing a substrate having a transparent conductive film using the same {A SOLUTION FOR FORMING A TRANSPARENT CONDUCTIVE FILM AND A PROCESS FOR FORMING A TRANSPARENT CONDUCTIVE FILM ON A SUBSTRATE USING THE SOLUTION}

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the measurement result by ESCA with respect to the gas with a transparent conductive film of this invention (glass substrate with ITO film of Examples 1-3).

FIG. 2 is a view showing a result of measuring the amount of indium by ESCA on a substrate with a transparent conductive film (quartz fiber with an ITO film of Example 5) prepared by the method for preparing a substrate with a transparent conductive film of the present invention. to be.

Fig. 3 shows indium in the depth direction of the ITO film by ESCA with respect to the substrate with a transparent conductive film (quartz fiber with ITO film of Example 5) prepared by the method for producing a substrate with a transparent conductive film of the present invention; It is a figure which shows the measurement result of tin content.

FIG. 4 is a diagram showing a result of measuring the amount of indium by ESCA on a quartz fiber (substrate with a transparent conductive film) with an ITO film prepared by the method for producing a substrate with a transparent conductive film of Comparative Example 2. FIG.

Fig. 5 shows the indium and tin contents in the depth direction of the ITO film by ESCA with respect to the quartz fiber with the ITO film (the gas with the transparent conductive film checked) prepared by the method for producing a substrate with the transparent conductive film of Comparative Example 2; It is a figure which shows a measurement result.

The present invention relates to a method for producing a substrate with a transparent conductive film-forming liquid and a transparent conductive film using the transparent conductive film-forming liquid.

Transparent conductive films (ITO films) are widely used in liquid crystal displays, electroluminescent displays, surface heating elements, touch panel electrodes, solar cells, etc., because of their excellent transparency and conductivity.

Since the transparent conductive film is used in such a wide field, it is required to have various sheet resistance values and transparency according to the purpose of use. For example, a transparent conductive film for flat panel display requires a low resistance and high transmittance film, and a high conductive and high transmittance film is required for a transparent conductive film for touch panel. In particular, the pen conductive touch panel transparent conductive film, which has recently been developed and expected to expand in the market, requires high position recognition accuracy, and thus a high resistance film having a sheet resistance of 200 to 3000? /? Is required. Here, sheet resistance value is a value calculated | required by the film thickness of a specific resistance / conductive film.

As a method of forming the transparent conductive film which has the above-mentioned desired sheet resistance value, the sputtering method, the electron beam method, the ion plating method, or the chemical vapor growth are described, for example, in JP-A-2001-35273 and JP-A-2002-133956. After forming a transparent electrode film by the method, the method of heat-processing a transparent conductive film in presence of the organic solvent of a predetermined density | concentration is described. In such a publication, indium trisacetylacetonate, indium trisbenzoyl methate, indium trichloride, indium nitrate, indium triisopropoxide, and the like are exemplified as an indium compound for the raw material for forming a transparent conductive film. Dimethyltin dichloride, dibutyltin dichloride, tetrabutyltin, stanier octoate, dibutyltin maleate, dibutyltin acetate, dibutyltin bisacetylacetonate, and the like. As the solvent, ketone solvents such as acetylacetone, acetone, methyl isobutyl ketone and diethyl ketone, alcohol solvents such as methanol, ethanol, propanol, isopropanol and butanol, ester solvents such as ethyl acetate and butyl acetate, and methyl cell Ether solvents, such as rosolve and tetrahydrofuran, aromatic hydrocarbons, such as benzene, toluene, and xylene, aliphatic hydrocarbons, such as hexane, heptane, octane, cyclohexane, etc. are illustrated.

However, in the above publication, a method for obtaining a transparent conductive film having a desired resistance value is described. The examination of a preferable combination for an indium compound and a tin compound as raw materials, a study of a preferable solvent for the combination, and a specific combination thereof There has been no examination of the uniformity of sheet resistance and transparency of the transparent conductive film in relation to. The present inventors considered further improvement of sheet resistance value and transparency uniformity in consideration of the future expansion of the use of a transparent conductive film, especially an ITO film.

Moreover, especially in the field of a liquid crystal display or an organic electroluminescent display, when alkali metal is contained in the organic compound which comprises the device element, such as a liquid crystal and an organic electroluminescent display, since it adversely affects the reliability of a device element, It is desirable to exclude alkali metals as much as possible.

In the fabrication of device elements, for example, when a low-cost soda lime substrate (abbreviation: SLG substrate) is used as a substrate (glass substrate) of a transparent conductive film, alkali metal from the gas itself is diffused in the organic compound constituting the device element. and a silicon oxide film (SiO ₂ film) in order to prevent the remarkable reliability of the device decreases used as the undercoat layer. However preventing the diffusion of alkali metal, and alkali to the transparent electrode film itself to form a film on the SiO ₂ film If metal is contained, it will diffuse into the device element and as a result the SiO ₂ film will not function. Therefore, it is desired to prevent the fall of the reliability of the device element derived from an alkali metal.

As the film formation method of such a transparent conductive film, there are a physical film formation method using a physical phenomenon in vacuum such as sputtering method and a chemical film formation method using chemical reaction such as dipping method.

However, in the case of forming a film on a substrate having a curved surface or irregularities, when the physical film formation method such as the sputtering method is used, the physical film formation method is uniform from the curved portion or the uneven portion in that the physical film formation method is deposited and formed from one direction of the substrate. It is difficult to form a transparent conductive film having a film thickness. Specifically, for example, in the case of forming a transparent conductive film on a quartz fiber, in a physical film formation method such as a sputtering method, the quartz fiber must be rotated during film formation so that the film thickness becomes uniform, and the control of the rotational speed is very difficult. It is difficult to form a transparent conductive film having a uniform film thickness.

In addition, in the dipping method, an example of a chemical film forming method, the transparent conductive film forming liquid can be uniformly applied to a curved or uneven gas, but it is difficult to uniformly remove the solvent during the thermal decomposition and drying in the next step. It is difficult to form a transparent conductive film with a uniform film thickness. Therefore, there is a need for a method capable of forming a film of uniform thickness on a substrate having curved or uneven surfaces.

The present invention has been made in view of the above circumstances, and an object of the present invention is a transparency having a transparent conductive film forming liquid capable of forming a very uniform transparent conductive film in sheet resistance and transparency, and a transparent conductive film having a very uniform transparency in sheet resistance and transparency. It is providing the manufacturing method of the gas with a whole film.

Another object of the present invention is to provide a transparent conductive film forming liquid capable of forming a transparent conductive film that can improve the reliability of a device element, and a transparent conductive film that can easily prepare a substrate with a transparent conductive film that can improve the reliability of a device element. It is providing the manufacturing method of this attached gas.

Moreover, the subject of this invention is providing the manufacturing method of the base with a transparent conductive film which can form a highly uniform transparent conductive film easily in the base body which has curved surface or unevenness | corrugation.

The present inventors have made intensive studies to form a more uniform film-like transparent conductive film, and as a result, the indium compound represented by the following formula [1] is used as the indium compound contained in the transparent conductive film-forming liquid for forming the transparent conductive film. And using a tin compound represented by the following formula [2] as a tin compound and using a β-diketone compound as a solvent for dissolving these, it has been found that a more uniform film-like transparent conductive film can be formed. Came to complete.

In addition, as a result of intensive studies to improve the reliability of device elements in fields such as liquid crystal displays and organic EL displays, the amount of alkali metal contained in the transparent conductive film forming liquid for forming the transparent conductive film is specified (2 mass ppm). By setting it as follows, it discovered that the reliability of device blocking can be improved significantly, and came to complete this invention.

In addition, as a result of careful examination of a method of uniformly forming a transparent conductive film on a curved or uneven gas, it is possible to form a uniform film on a curved or uneven gas by using a pyrosol process method. To discover and complete the present invention. That is, in the pyrosol process method, the transparent conductive film forming liquid is made into a mist by ultrasonic waves, and is introduced into a film forming furnace heated with air or the like as a carrier gas, so that the transparent conductive film forming liquid becomes a gas in a uniform form. Since it is brought into contact with and thermally decomposed, the transparent conductive film having a uniform film thickness can be formed even in the curved portion or the uneven portion.

That is, the present invention is formula [1]

In (R ¹ COCHCOR ² ) ₃ [1]

(In formula, R <^1> and R <^2> respectively independently represents a C1-C10 alkyl group or a phenyl group.), And the indium compound represented by Formula [2]

(R ³ ) ₂ Sn (OR ⁴ ) ₂ [2]

In the formula, R ³ represents an alkyl group having 1 to 10 carbon atoms, and R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms. The solvent for dissolving the liquid (claim 1) and the indium compound represented by the formula [1] and the tin compound represented by the formula [2] is a β-diketone compound, wherein the transparent conductive film-forming liquid according to claim 1 ( Claim 2) and the quantity of the alkali metal to contain are 2 mass ppm or less, It is related with the transparent conductive film formation liquid (claim 3) of Claim 1 characterized by the above-mentioned.

In another aspect, the present invention is a method for forming a transparent conductive film to form a transparent conductive film directly on the substrate or through an intermediate film, the formula [1]

In (R ¹ COCHCOR ² ) ₃ [1]

Wherein R ¹ and R ² each independently represent an alkyl group or a phenyl group having 1 to 10 carbon atoms; and an indium compound represented by the formula [2]

(R ³ ) ₂ Sn (OR ⁴ ) ₂ [2]

In the formula, R ³ represents an alkyl group having 1 to 10 carbon atoms, and R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms. A method for producing a gas with a transparent conductive film (Claim 4) characterized by forming a transparent conductive film by chemical thermal decomposition, or dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2] The method for producing a gas with a transparent conductive film according to claim 4, wherein the solvent is a β-diketone compound (claim 5), and the amount of the alkali metal contained is 2 mass ppm or less. The manufacturing method (claim 6) of the base material with a transparent conductive film of description is provided.

In another aspect, the present invention is a method for producing a substrate with a transparent conductive film (claim 7) characterized in that the transparent conductive film is formed by a pyrosol process method directly or through an intermediate film on a curved or uneven surface of the substrate (claim 7) or curved surface Or a transparent conductive film is formed by a pyrosol process method through an intermediate film formed by a pyrosol process method on a gas having an uneven shape (claim 8). Of a transparent conductive film-attached gas, characterized in that the transparent conductive film is formed by a pyrosol process method using the transparent conductive film forming liquid according to claim 1 directly or on an intermediate film having a curved or uneven shape. It relates to a method (claim 9).

Embodiment of the invention

In the following description, all aspects of the present invention will be described in common except that specific embodiments are described.

The 1st aspect of the transparent conductive film forming liquid of this invention is a formula [1].

In (R ¹ COCHCOR ² ) ₃ [1]

An indium compound represented by the formula and formula [2]

(R ³ ) ₂ Sn (OR ⁴ ) ₂ [2]

It is characterized by containing a tin compound represented by.

In formula [1], R <^1> and R <^2> represents a C1-C10 alkyl group or a phenyl group each independently (it is the same below), Specifically, For example, a methyl group, an ethyl group, n-propyl group, n-butyl group, t-butyl group etc. are mentioned. Among these, as the indium compound represented by the formula (1) indium tris acetylacetonate is particularly preferred that _{(In (CH 3 COCHCOCH 3)} 3).

In formula [2], R <^3> represents a C1-C10 alkyl group and R <^4> represents a C1-C10 alkyl group or a C1-C10 acyl group (following). Specifically, R ^{3 includes,} for example, a methyl group, ethyl group, n-propyl group, n-butyl group, t-butyl group, and as R ^4, for example, methyl group, ethyl group, n-propyl group, n-butyl group and acyl groups such as an alkyl group of t-butyl group, an acetyl group, and a propionyl group. Among these, the tin compound represented by the formula [2] is particularly preferably di-n-butyltin diacetate ((n-Bu) ₂ Sn (OCOCH ₃ ) ₂ ).

In the case of forming the transparent conductive film using the transparent conductive film forming liquid, the closer the thermal decomposition temperature of the indium compound and the tin compound contained in the transparent conductive film forming liquid is, the both can be uniformly diffused to form a uniform film quality. I think. In the transparent conductive film-forming liquid of the present invention, the indium compound represented by the formula [1] and the tin compound represented by the formula [2] have a close pyrolysis temperature, specifically, the indium trisacetylacetonate is around 320 ° C, and di-n Butyl tin diacetate is around 360 ° C.

Therefore, in the case of forming the transparent conductive film using the transparent conductive film forming liquid of the present invention, when the indium compound and the tin compound are decomposed by heat to be deposited on a gas or an intermediate film, the indium compound and the tin compound are almost at a predetermined temperature. At the same time, thermal decomposition causes both to be uniformly diffused and deposited (deposited), and a very uniform film can be formed to form a transparent conductive film having very uniform conductivity and transparency. In addition, after coating the transparent conductive film-forming liquid, when the indium compound and the tin compound are decomposed by heat to be fixed on a gas or an intermediate film, the indium compound and the tin compound are almost at a predetermined temperature in drying and / or firing after coating. At the same time, it is considered to be thermally decomposed and uniformly diffused to be fixed on the gas or the intermediate film, and the film quality is formed to be very uniform, thereby forming a transparent conductive film having very uniform conductivity and transparency. Thus, since the film formed using the transparent conductive film formation liquid of this invention is excellent in electroconductivity and transparency, it can be widely used for a liquid crystal display, an electroluminescent display, a surface heating body, a touch panel electrode, a solar cell.

The transparent conductive film forming liquid of the present invention is not particularly limited in content ratio as long as it contains an indium compound and a tin compound, but contains In more than Sn in the tin compound by mass in the indium compound (the transparent conductive film formed is ITO Film), more preferably 0.001 to 0.5 and more preferably 0.05 to 0.35 of Sn in the tin compound relative to In1 in the indium compound by mass ratio.

By containing an indium compound and a tin compound in the range of the mass ratio, it is possible to form a transparent conductive film having excellent transparency and uniformity of resistance, and the transparent conductive film having such a resistance value is particularly useful as a transparent electrode for a touch panel, for example. .

Although the transparent conductive film forming liquid in 1st aspect of this invention contains the indium compound represented by Formula [1], another indium compound can also be used together. Preferably thermally decomposed as the indium compound used in combination that indium oxide and, for example, phosphorus trichloride indium (InCl _3), indium nitrate _{(In (NO 3) 3)} , indium triisopropoxide (In (OiPr) _3), etc. Can be mentioned.

When using another indium compound together, it is preferable that the indium compound represented by Formula [1] is contained 80 mass% or more in all the indium compounds, It is more preferable that 90 mass% or more is contained, 95 mass% or more It is more preferable to contain it, and it is more preferable that it contains more indium compounds represented by Formula [1].

Although the transparent conductive film forming liquid in 1st aspect of this invention contains the tin compound represented by Formula [2], another tin compound can also be used together. Thermally decomposed as the tin compounds are used in combination preferably is stannic oxidizing agent, and for example, chloride of tin, dimethyl tin dichloride, dibutyl tin dichloride, tetrabutyl tin, Stanislaw earth octoate (Sn (OCOC ₇ H _{15 2} ), dibutyltin maleate, dibutyltin bisacetylacetonate, and the like.

When using another tin compound together, it is preferable that the tin compound represented by Formula [2] is contained 80 mass% or more in all the tin compounds, It is more preferable that 90 mass% or more is contained, 95 mass% or more It is more preferable to contain it, and it is more preferable that it contains more tin compounds represented by Formula [2].

The transparent conductive film-forming liquid of the present invention is, in addition to the indium compound and the tin compound, as a third component, Group 2 elements such as Mg, Ca, Sr, Ba, etc., Group 3 elements such as Sc, Y, La, Ce, etc. Lanthanoids such as, Nd, Sm, Gd, Group 4 elements such as Ti, Zr, Hf, Group 5 elements such as V, Nb, Ta, Group 6 elements such as Cr, Mo, W, Mn, etc. Group 7 elements, Group 9 elements such as Co, Group 10 elements such as Ni, Pd, Pt, Group 11 elements such as Cu, Ag, Group 12 elements such as Zn, Cd, B, Al, Ga Group 13 elements, such as Si, Ge, Pb, etc., Group 15 elements, such as P, As, and Sb, Group 16 elements, such as Se and Te, etc. are contained, or these compounds are contained It is also preferable.

The addition ratio of these elements is preferably about 0.05 to 20 atomic% with respect to indium, and the addition ratio varies depending on the added element, so that an element and an addition amount suitable for the desired resistance value can be appropriately selected.

As an organic solvent used for the transparent conductive film formation liquid of this invention, ketone solvents, such as acetone, methyl isobutyl ketone, diethyl ketone, alcohol solvents, such as methanol, ethanol, propanol, isopropanol, butanol, ethyl acetate, butyl acetate Ester solvents such as esters, ether solvents such as methylcellosolve, tetrahydrofuran, aromatic hydrocarbons such as benzene, toluene, xylene, and aliphatic hydrocarbons such as hexane, heptane, octane, cyclohexane, and the like. .

The type and amount of these organic solvents vary depending on the set value of the sheet resistance of the transparent conductive film and the like, and can be appropriately determined according to the type of the transparent conductive film, the film thickness of the transparent conductive film, the type of organic solvent used, the heating temperature, the heating time and the like. . For example, the sheet resistance value can be made lower by making other conditions the same and adding a large amount of the organic solvent which is easy to thermally decompose. By appropriately selecting and setting the type, addition amount, and heating temperature of the organic solvent to be used as described above, a transparent conductive film having a desired sheet resistance can be obtained.

Moreover, the 2nd aspect of the transparent conductive film formation liquid of this invention is the said Formula [1].

In (R ¹ COCHCOR ² ) ₃ [1]

An indium compound represented by the formula and formula [2]

(R ³ ) ₂ Sn (OR ⁴ ) ₂ [2]

It is characterized by containing the (beta) -diketone compound which melt | dissolves the tin compound represented by this, and also the indium compound represented by said Formula [1], and the tin compound represented by Formula [2].

As the β-diketone compounds, β-ketone acid esters such as β-diketones such as acetylacetone, methyl acetoacetate and ethyl acetoacetate, β-dicarboxylic acid esters such as dimethyl malonate and diethyl malonate are used. Among these, acetylacetone is preferable. By using acetylacetone, the effect of this invention can be exhibited more effectively.

In the transparent conductive film forming liquid in the second aspect of the present invention, the indium compound represented by the formula [1] and the tin compound represented by the formula [2] are sufficiently dissolved, and the composition ratio in the transparent conductive film forming liquid does not change. It is thought that a transparent conductive film of uniform film quality can be formed by forming a transparent conductive film using this.

Moreover, the (beta) -diketones compound in the transparent conductive film forming liquid of 2nd aspect of this invention will be restrict | limited especially if the indium compound represented by Formula [1] and the tin compound represented by Formula [2] can be melt | dissolved. However, β-diketones such that the total metal powder (In + Sn) of the indium compound represented by the formula [1] and the tin compound represented by the formula [2] contain 0.07 or less relative to the β-diketone compound 1 by mass ratio It is preferable to add a compound, it is more preferable to add so that it may become a range 0.00001-0.07, and it is still more preferable to add so that it may become a range 0.001-0.04. By using the β-diketone compounds in the above range, the indium compound represented by the formula [1] and the tin compound represented by the formula [2] can be dissolved under an appropriate concentration to form a more uniform film-like transparent conductive film. It becomes possible.

Moreover, the transparent conductive film forming liquid of 2nd aspect of this invention can also use together the other solvent demonstrated by the said 1st aspect with the said beta-diketone compound.

Although the kind and addition amount of the solvent used together vary with the setting value of the sheet resistance value of a transparent conductive film, the formation method of a film, etc., 80 mass% or more of (beta) -ketones are contained in all the solvents so that the effect of this invention can be exhibited more effectively. It is preferable to exist, it is more preferable to contain 90 mass% or more, It is more preferable to contain 95 mass% or more, It is more preferable that it contains more β-diketone compounds.

The transparent conductive film forming liquid in 2nd aspect of this invention can use together the other indium compound demonstrated above about 1st aspect, and can also use together the other tin compound demonstrated above about 1st aspect.

Moreover, the transparent conductive film forming liquid of this invention of 3rd aspect of this invention contains an indium compound and a tin compound, and is characterized by the content of the alkali metal in a transparent conductive film forming liquid being 2 mass ppm or less.

The transparent conductive film formed using the transparent conductive film forming liquid whose content of an alkali metal is 2 mass ppm or less can significantly improve the reliability of a device element, without adversely affecting a device element especially in the field | areas, such as a liquid crystal display.

In the transparent conductive film forming liquid of the 3rd aspect of this invention, although content of an alkali metal needs to be 2 mass ppm or less as mentioned above, it is preferable that it is 1.5 mass ppm or less, It is more preferable that it is 1 mass ppm or less, It is 0.1 mass It is more preferable that it is ppm or less.

Herein, the alkali metal refers to lithium, sodium, potassium, rubidium, cesium, and francium. In consideration of the possibility of being actually incorporated into the transparent conductive film forming liquid, the total content of sodium and potassium may be managed.

As the indium compound in the third transparent conductive film of the solar-forming solution of the present invention, preferably is pyrolysis which the indium oxide, for example indium tris acetylacetonate _{(In (CH 3 COCHCOCH 3)} 3), indium tris benzoyl meta Nate (In (C ₆ H ₅ COCHCOC ₆ H ₅ ) ₃ ), Indium trichloride (InCl ₃ ), Indium nitrate (In (NO ₃ ) ₃ ), Indium triisopropoxide (In (Oi-Pr) ₃ ), etc. Can be illustrated.

As a tin compound in the transparent conductive film forming liquid of 3rd aspect of this invention, it is preferable to thermally decompose and become a 2nd tin oxide, For example, a tin tin chloride, dimethyl tin dichloride, dibutyl tin dichloride, tetrabutyl Tin, stanier octoate (Sn (OCOC ₇ H ₁₅ ) ₂ ), dibutyltin maleate, dibutyltin bisacetylacetonate, dibutyltin diacetate, and the like.

Moreover, if the transparent conductive film forming liquid of 3rd aspect of this invention contains an indium compound and a tin compound, the kind in particular will not be restrict | limited, but an indium compound,

Equation 1

In (R ¹ COCHCOR ² ) ₃ [1]

Indium compounds represented by the above, wherein the tin compound is the formula [2]

(R ³ ) ₂ Sn (OR ⁴ ) ₂ [2]

It is preferable that it is a tin compound represented by. Among these, the indium compound represented by the formula [1] is particularly preferably indium trisacetylacetonate (In (CH ₃ COCHCOCH ₃ ) ₃ ), and the tin compound represented by the formula [2] is di-n-butyltin di. Particular preference is given to acetate ((n-Bu) ₂ Sn (OCOCH ₃ ) ₂ ).

Hereinafter, the manufacturing method of the base with a transparent conductive film of this invention is demonstrated.

In the method of manufacturing a substrate with a transparent conductive film of the present invention, a transparent conductive film is formed on a substrate directly or through an intermediate film to prepare a substrate having a transparent conductive film thereon. The transparent conductive film is formed by chemical thermal decomposition using the transparent film forming liquid in any one of the third aspect. That is, a transparent conductive film is formed by chemical thermal decomposition using the transparent conductive film forming liquid.

The chemical pyrolysis method here refers to a method of thermally decomposing an indium compound and a tin compound contained in a transparent conductive film forming solution and depositing it on a gas or an intermediate film, and after coating the transparent conductive film forming solution, the indium compound and tin compound It refers to a method of decomposing and fixing on a gas or an interlayer, for example, a spray method, a dip coating method, a spin coating method, an LB method, a sol gel method, a liquid phase epitaxy method, a thermal CVD method, a plasma CVD method, a MOCVD method, a pyrosol CVD methods (chemical vapor deposition) such as process method (atmospheric pressure CVD method by ultrasonic mist), SPD method, Cat-CVD method, and the like, and the like, and among these, pyrosol process method is particularly preferred. By using the pyrosol process method, a transparent conductive film having a more uniform film quality can be produced. In the pyrosol process method, since the transparent conductive film forming solution is introduced into the conveyor (film forming apparatus), there is no chance of contact with the alkali metal until the transparent conductive film is formed, so that a transparent conductive film having a low content of alkali metal is produced. It can be formed very easily.

According to the method for producing a substrate with a transparent conductive film of the present invention, by using the transparent conductive film forming liquid of the present invention described above, the indium compound and the tin compound close to the pyrolysis temperature are uniformly diffused under a predetermined temperature to obtain a uniform film quality. A transparent conductive film can be formed. Moreover, by using the transparent conductive film forming liquid of 2nd aspect of this invention demonstrated above, the indium compound represented by Formula [1] and the tin compound represented by Formula [2] are melt | dissolved sufficiently, and the composition ratio in a transparent conductive film forming liquid changes. Since it is not possible, it is considered that a transparent conductive film having a uniform film quality can be formed. Further, by using the transparent conductive film-forming liquid of the third aspect of the present invention described above, it is possible to easily produce a substrate with a transparent conductive film that can greatly improve the reliability of the device element without adversely affecting the device element in a liquid crystal display or the like. Can be.

Specifically, in the case where the indium compound and the tin compound in the transparent conductive film forming solution are thermally decomposed and deposited on the gas or the intermediate film, the indium compound and the tin compound are thermally decomposed almost simultaneously under a predetermined temperature so that both are uniformly diffused and deposited. Since it is considered to be (deposition), a film having a very uniform film quality can be formed to form a transparent conductive film having very uniform conductivity and transparency. In addition, after coating the transparent conductive film-forming liquid, when the indium compound and the tin compound are decomposed by heat and fixed on a gas or an intermediate film, the transparent conductive film-forming liquid is uniformly coated, and then dried after coating and / or In baking, the indium compound and the tin compound near the pyrolysis temperature are thermally decomposed almost simultaneously under a predetermined temperature, so that both are uniformly diffused and fixed on the gas or the intermediate film, so that the film quality is very uniform. Thus, a transparent conductive film having very uniform conductivity and transparency can be formed.

In addition, since the transparent conductive film prepared by the method for producing a substrate with a transparent conductive film of the present invention has excellent conductivity and transparency, it can be widely used in liquid crystal displays, electroluminescent displays, surface heating elements, touch panel electrodes, solar cells, and the like. . Moreover, in the manufacturing method of the gas with a transparent conductive film of this invention, a homogeneous film can be formed simply by using the chemical pyrolysis method which is a general method of film formation.

The interlayer film may be a single layer film or a film of two or more layers. Examples of such an interlayer include a silicon oxide film, a polysilane film formed of an organopolysilane compound, an MgF ₂ film, a CaF ₂ film, a composite oxide film of SiO ₂ and TiO ₂ , and the like. These interlayer films are formed to prevent diffusion of Na ions, for example, when using soda glass as a substrate. Moreover, antireflection or transparency can also be improved by forming the base film of refractive index different from the transparent conductive film, preferably low refractive index. These films can be formed by a generally known film forming method, for example, a sputtering method, a CVD method, a spraying method, a dipping method, or the like, and the film thickness is not particularly limited but is usually about 20 to 200 nm.

The gas may be in the form of a sheet (substrate), honeycomb, fiber, bead, foam, or the like. The gas is not particularly limited as long as the components of the transparent conductive film forming liquid have heat resistance at a temperature causing thermal decomposition. For example, a glass substrate, a ceramic substrate, a metal substrate, etc. are mentioned. Among these, it is preferable to use a glass substrate in the manufacturing method of the base body with a transparent conductive film of this invention. As a glass substrate, silicate glass (quartz glass), alkali silicate glass, soda-lime glass, kali lime glass, lead glass, barium glass, borosilicate glass, etc. are mentioned, for example.

In addition, the film thickness of the transparent conductive film formed by the method for producing a substrate with a transparent conductive film of the present invention is not particularly limited and may be appropriately selected depending on the purpose thereof, but an ITO film having a sheet resistance of 30 μs / square or less is formed. In the case of forming an ITO film having a sheet resistance of generally 50 nm or more and having a sheet resistance of 60 to 200 mW / square, it is generally about 30 nm, and generally 10 to 10 when forming an ITO film having a sheet resistance of 200 to 3000 mW / square. 25 nm.

In the method for producing a substrate with a transparent conductive film of the present invention, in the case of using the pyrosol process method, an ultrasonic atomizing method is used for the transparent conductive film forming solution in which an indium compound and a tin compound are dissolved in an organic solvent. Thus, as aerosols composed of small droplets having relatively constant granularity, the indium compound and the tin compound are thermally decomposed to maintain a temperature at which the indium oxide and the ditin tin oxide are formed at a uniform temperature, for example, 300 to 800 ° C. By supplying the gas phase in the furnace, the indium compound and the tin compound are vaporized in the furnace and reacted in the gas phase from the gaseous state to form a transparent conductive film.

When using a gas having a curved or uneven shape, it is preferable to form a transparent conductive film by a pyrosol process method directly or through an intermediate film. By using the pyrosol process method, it is possible to easily form a transparent conductive film having a very uniform film thickness on a substrate having a curved surface or irregularities. That is, although it is generally difficult to form a film with a uniform film thickness on a gas having a curved surface or uneven shape, when using the pyrosol process method, a metal compound sublimated by heating to form a gaseous state is formed on a curved surface or uneven portion. By uniformly contacting and thermally decomposing, it is possible to produce a substrate with a transparent conductive film having a transparent conductive film having a very uniform film thickness as a whole.

In addition, when a film is formed on the plate using the pyrosol process method, the metal compound sublimated by heating returns to the rear side (the outer peripheral part of the back side) of the plate, which causes a poor conductivity in the touch panel. There is a case. Therefore, it is necessary to control so as not to return to the back side of the flat plate, but in a gas having a curved surface or uneven shape (fiber-shaped gas or spherical gas), it is rather possible to use such a return to the outer surface of the curved surface or unevenness. Therefore, a transparent conductive film having a uniform film thickness can be formed on the inner surface (in the case of a hemispherical gas such as a rice bowl shape).

The gas capable of forming the transparent conductive film by the pyrosol process method is not particularly limited as long as it is a gas having a curved or uneven shape, and a sheet-shaped base (substrate) having a curved or uneven shape, and a honeycomb-based gas. Although it may be a fiber-shaped gas, a spherical gas, a foamed gas, etc., it is preferable that it is a fiber-shaped gas or spherical gas. The base having the curved surface is preferably a base having a curved surface having a radius of curvature of about 1 to 1000 mm.

Here, the fiber-like gas refers to a fibrous gas having a diameter of about 0.01 to 15 mm, and the spherical gas includes an elliptical gas, a gas in which a part of a sphere is separated (for example, a hemisphere), a precursor gas, and the like. It means that it is 30% or more, Preferably it is 50% or more, More preferably, it is 80% or more of this gas whole surface (film formation part).

The substrate having the fiber-shaped transparent conductive film attached thereto is particularly useful as an optical communication cable, and particularly preferably a quartz fiber. In addition, a substrate having a spherical transparent conductive film is particularly useful as an electrode for illumination.

In addition, the transparent conductive film which can be formed by the pyrosol process method on a curved or uneven substrate according to the present invention is not limited to an indium oxide film (ITO film) doped with tin, and tin oxide doped with fluorine. The film (FTO film), the tin oxide film (ATO film) doped with antimony, the zinc oxide film doped with indium, the zinc oxide film doped with aluminum, etc. can also be illustrated.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples, but the technical scope of the present invention is not limited to these examples.

Example 1

Indium trisacetylacetonate (In (AcAc) ₃ ) was dissolved in acetylacetone at a molar concentration of 0.2 mol / L to obtain a yellow transparent solution. Di-n-butyltin diacetate was added to this solution as a tin compound so that Sn / In might be 5 mass%, and the film formation liquid (transparent conductive film formation liquid) of ITO was prepared. The indium trisacetylacetonate is 0.03 mass ppm, the acetylacetone is 0.05 mass ppm and the di-n-butyltin diacetate is 0.03 mass ppm with respect to the alkali metal content.

On the glass substrate (SLG substrate) which undercoated the SiO ₂ film by the dipping method while adjusting the chemical thermal decomposition amount by the mist of the ITO film forming liquid by the pyrosol process method using this ITO film forming liquid. An ITO film having a thickness of 20 nm was formed to obtain a glass substrate (substrate with a transparent conductive film) with an ITO film having a colorless and transparent ITO film.

Example 2

In the same manner as in Example 1, an ITO film having a thickness of 40 nm was formed on the glass substrate to obtain a glass substrate with an ITO film having a transparent ITO film.

Example 3

In the same manner as in Example 1, an ITO film having a thickness of 200 nm was formed on the glass substrate to obtain a glass substrate with an ITO film having a transparent ITO film.

Comparative Example 1

Indium trisacetylacetonate was dissolved in acetylacetone at a molar concentration of 0.2 mol / L to obtain a yellow transparent solution. Tri-n-octyl tin oxide was added to this solution as a tin compound so that Sn / In = 5 mass%, and the ITO membrane formation liquid was prepared.

On the glass substrate (SLG substrate) on which the SiO ₂ film was undercoated by the dipping method while adjusting the amount of chemical pyrolysis due to the mist of the ITO film forming liquid by the pyrosol process method using this ITO film forming liquid. A 30 nm thick ITO film was formed to prepare a glass substrate with an ITO film having a yellowish transparent ITO film.

Example 4

Indium trisacetylacetonate was dissolved in acetylacetone at a molar concentration of 0.2 mol / L to obtain a yellow transparent solution. Di-n-butyltin diacetate having an alkali metal content of 0.03 mass ppm was added to the solution so that Sn / In = 5 mass%, and sodium stearate was further added so that Na / In = 10 mass ppm. An ITO film formation liquid was prepared.

On the glass substrate (SLG substrate) on which the SiO ₂ film was undercoated by the dipping method while adjusting the amount of chemical pyrolysis due to the mist of the ITO film forming liquid by the pyrosol process method using this ITO film forming liquid. A 40 nm thick ITO film was formed to prepare a glass substrate with an ITO film.

<Evaluation>

The resistivity value of the glass substrate with an ITO film which concerns on said Examples 1-4 and Comparative Example 1 was measured using the lorista (made by Mitsubishi Chemical Corporation), and sheet resistance value was computed. In addition, sheet resistance value is a value calculated | required by the film thickness of a specific resistance / conductive film. The light transmittance at a wavelength of 550 nm for the arbitrarily selected portions a to c (three locations) of the glass substrate with ITO film according to Examples 1 to 4 and Comparative Example 1 was determined by using a spectrophotometer (Hitachi Works). Measured using. In addition, content of indium and tin in the depth direction of the ITO film | membrane of the glass substrate with an ITO film which concerns on Examples 1-3 and Comparative Example 1 was measured by ESCA. In addition, the ITO film of the glass substrate with an ITO film which concerns on said Examples 1-4 was etched and dissolved with the acid, and the content of alkali metal was measured with the ICP emission spectrophotometer.

The measurement results of sheet resistance are shown in Table 1 below, the results of light transmittance measurements are shown in Table 2 below, and the measurement results of alkali metal amounts are shown in Table 3 below. Moreover, the measurement result by ESCA with respect to the glass substrate with an ITO membrane which concerns on Examples 1-3 is shown in FIG.

ITO film thickness (nm) Sheet Resistance of ITO Film (Ω / □) Example 1 20 500 Example 2 40 100 Example 3 200 10 Example 4 40 100 Comparative Example 1 30 10000

Light transmittance a (%) of ITO membrane Light transmittance b of ITO membrane (%) Light transmittance c (%) of ITO membrane Example 1 90 90 91 Example 2 88 89 89 Example 3 80 81 80 Example 4 88 88 89 Comparative Example 1 88 86 90

Content of alkali metals (mass ppm) Example 1 0.1 Example 2 0.1 Example 3 0.1 Example 4 12

(result)

As is clear from Table 1, by changing the film thickness by the method for producing a substrate with a transparent conductive film of the present invention, a substrate with an ITO film having a sheet resistance of 10 to 500 kPa / square can be produced, and corresponding to various applications. It was found that a gas with an ITO film having an ITO film having a desired sheet resistance value can be obtained.

As is clear from Table 2, it was found that the glass substrates having the ITO films of Examples 1 to 4 related to the present invention had almost the same light transmittance and uniform film transparency at arbitrary portions.

In addition, as is apparent from Table 3, the ITO film in the glass substrate with ITO film of Examples 1 to 3 according to the present invention has an alkali metal content of 0.1 mass ppm, which is used to produce device elements such as liquid crystal displays. It is possible to manufacture more reliable device elements. On the other hand, the ITO film in the glass substrate with ITO film which concerns on Example 4 has 12 mass ppm of alkali metal content, and when it uses this, and produces device elements, such as a liquid crystal display, it becomes a low reliability device element, It is limited.

As is clear from Fig. 1, in the glass substrate with ITO membranes of Examples 1 to 3 according to the present invention, the content of tin is almost constant, and a film in which indium and tin are uniformly dispersed on the surface and inside of the membrane is formed. It turned out. On the other hand, in the gas with the ITO film | membrane which concerns on the comparative example 1, tin was not detected by ESCA measurement, and it turned out that tin was simply decomposed and it does not become a film with indium.

Example 5

Using the ITO film-forming liquid of Example 1, an ITO film was formed by forming an ITO film on a quartz fiber having a diameter of 500 µm while adjusting the amount of chemical thermal decomposition by misting of the ITO film-forming liquid by a pyrosol process method. The obtained quartz fiber (gas with a transparent conductive film) was obtained.

Comparative Example 2

Using a target of Sn / In = 10% by mass of ITO (sintered body of In ₂ O ₃ and SnO ₂ ), a quartz fiber having a diameter of 500 μm was sputtered in 20 minutes by sputtering under the conditions of an oxygen partial pressure of 0.7 kPa. An ITO film was formed while rotating to obtain a quartz fiber with an ITO film.

(evaluation)

The quartz fiber with the ITO film according to Example 5 and Comparative Example 2 was cut into a length of about 1 cm at an arbitrary position, and the amount of indium was measured using ESCA at the other four surface portions to determine the film thickness of the ITO film. Investigate. Similarly, the content (content) of indium and tin in the depth direction of the ITO film was measured.

The measurement result of the indium amount with respect to the quartz fiber with an ITO film of Example 5 is shown in FIG. 2, and the measurement result of content of indium and tin in the depth direction of an ITO film is shown in FIG. In addition, the measurement result of the amount of indium with respect to the quartz fiber with ITO film of the comparative example 2 is shown in FIG. 4, and the measurement result of content of indium and tin in the depth direction of an ITO film is shown in FIG.

(result)

As is clear from Fig. 2, in the quartz fiber with an ITO film according to Example 5, the ITO film had a film thickness of about 95 to 105 nm, whereby a very uniform film thickness of ITO film could be formed. As is apparent from Fig. 3, in the quartz fiber with an ITO film according to Example 5, the tin content was almost constant, and a film in which indium and tin were uniformly dispersed on the surface and inside of the film was formed.

In contrast, in the quartz fiber with an ITO film according to Comparative Example 2, as apparent from Fig. 4, the film thickness of ITO is large in the range of about 70 to 100 nm, and the formed ITO film is an ITO film having a non-uniform film thickness. It was. In addition, as is apparent from FIG. 5, in the quartz fiber with an ITO film according to Comparative Example 2, the tin distribution in the film was uneven due to the high content of tin in the film surface.

According to the transparent conductive film forming liquid of the present invention, a very uniform transparent conductive film can be formed in the sheet resistance value, the transparency, and the distribution of the indium compound and the tin compound in the depth direction of the transparent conductive film. Moreover, according to the transparent conductive film formation liquid of this invention, the transparent conductive film which can improve the reliability of a device element can be formed.

In addition, according to the method for preparing a substrate with a transparent conductive film of the present invention, a substrate with a film having a transparent conductive film that is very uniform in sheet resistance, transparency, and distribution of indium compound and tin compound in the depth direction of the transparent conductive film can be prepared. Can be. Moreover, according to the manufacturing method of the base material with a transparent conductive film of this invention, the base material with a transparent conductive film which can improve the reliability of a device element can be manufactured easily.

In addition, according to the method for producing a substrate with a transparent conductive film of the present invention, a transparent conductive film having a very uniform film thickness is formed on a substrate having a curved surface or irregularities, so that a substrate with a transparent conductive film having a very uniform film thickness can be easily formed. It can manufacture.

Claims (9)

Formula [1] In (R ¹ COCHCOR ² ) ₃ [1] (In formula, R <^1> and R <^2> respectively independently represents a C1-C10 alkyl group or a phenyl group.), And the indium compound represented by Formula [2] (R ³ ) ₂ Sn (OR ⁴ ) ₂ [2] In the formula, R ³ represents an alkyl group having 1 to 10 carbon atoms, and R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms. liquid. The transparent conductive film-forming liquid according to claim 1, wherein the solvent for dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2] is a β-diketone compound. The transparent conductive film forming liquid according to claim 1 or 2, wherein the amount of alkali metal to be contained is 2 mass ppm or less. By forming a transparent conductive film on the substrate (directly or through an intermediate film) to produce a substrate with a transparent conductive film, On the gas or interlayer [1] In (R ¹ COCHCOR ² ) ₃ [1] Wherein R ¹ and R ² each independently represent an alkyl group or a phenyl group having 1 to 10 carbon atoms; and an indium compound represented by the formula [2] (R ³ ) ₂ Sn (OR ⁴ ) ₂ [2] In the formula, R ³ represents an alkyl group having 1 to 10 carbon atoms, and R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an acyl group having 1 to 10 carbon atoms. A method for producing a substrate with a transparent conductive film, characterized in that the transparent conductive film is formed by chemical thermal decomposition. The method for producing a gas with a transparent conductive film according to claim 4, wherein the solvent for dissolving the indium compound represented by the formula [1] and the tin compound represented by the formula [2] is a β-diketone compound. The method for producing a substrate with a transparent conductive film according to claim 4 or 5, wherein the amount of alkali metal contained is 2 mass ppm or less. delete delete A transparent conductive film is formed on a substrate having a curved or uneven shape by the pyrosol process method using the transparent conductive film forming liquid according to claim 1 directly or through an intermediate film. Manufacturing method.

Images