JP3352772B2 - Transparent conductive film and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a transparent conductive film and a method for producing the same.

[0002]

2. Description of the Related Art Since liquid crystal display devices can be reduced in weight and thickness and have low driving voltage, they are actively introduced into OA equipment such as personal computers and word processors. And the liquid crystal display device having the above-mentioned advantages is inevitably increased in area,
With the trend toward more pixels and higher definition, there is a need for a high-quality liquid crystal display element free from display defects. One of the important factors in obtaining a high quality liquid crystal display element is a transparent electrode, and an ITO film is currently dominant as the transparent electrode.

[0003]

SUMMARY OF THE INVENTION However, ITO
The film has the disadvantage that the moisture resistance is relatively low and the transparency tends to decrease due to moisture. Further, in order to obtain an element or a device having high electric field response, use of a transparent conductive film having high electron mobility is desired. SUMMARY OF THE INVENTION An object of the present invention is to provide a transparent conductive film that has better moisture resistance and higher electron mobility than an ITO film, and a method for manufacturing the same.

[0004]

Means for Solving the Problems] The transparent conductive film of the present invention to achieve the above object, Ri Na <br/> a substantially triple rutile structure compound, the electron mobility of 40 cm ² / V · sec or more der (Hereinafter, this transparent conductive film is referred to as a transparent conductive film I).

Another transparent conductive film of the present invention that achieves the above object is Sn, Al, Sb, Ga, In and Ge.
Consisting essentially of a triple rutile structure compound doped with at least one element selected from the group consisting of: wherein the doping amount of the element is 20 at% with respect to the total amount of the cation elements constituting the triple rutile structure compound. It is characterized by the following (hereinafter, this transparent conductive film is referred to as a transparent conductive film II).

On the other hand, the method for producing a transparent conductive film of the present invention which achieves the above object is to prepare a coating solution in which a predetermined amount of a basic starting material of a triple rutile structure compound is dissolved, and apply the coating solution to a substrate. After firing, a reduction treatment is performed (hereinafter, this method is referred to as method I).

Another method for producing the transparent conductive film of the present invention, which achieves the above object, comprises the steps of providing a predetermined amount of a basic starting material of a triple rutile structure compound, a Sn compound, an Al compound, a Sb compound, a Ga compound, and an In compound. And at least one dope material selected from the group consisting of
A coating solution is prepared by dissolving so that the ratio of the doping element to the total amount of the cation elements constituting the triple rutile structure compound is 20 at% or less. (Hereinafter, this method is referred to as method II).

Hereinafter, the present invention will be described in detail. First, the transparent conductive film I of the present invention will be described. The transparent conductive film I is substantially composed of a triple rutile structure compound as described above. Here, “substantially composed of a triple rutile structure compound” means that not only a pure triple rutile structure compound but also a compound containing impurities that are inevitably mixed in the production process may be included. Further, it may contain an oxide or an amorphous component of a cation constituting the triple rutile structure compound, for example, in a proportion of 50 wt% or less, preferably 20 wt% or less. Examples of the cation oxide include ZnO, S
_{b 2 O 3, Sb 2 O} 5, Nb 2 O 3, Nb 2 O 5, Mg
O and the like. Specific examples of the triple rutile structure compound include ZnSb ₂ O ₆ , ZnNb ₂ O ₆ , and MgSb ₂ O
₆ , MgNb ₂ O _{6 and the} like. The transparent conductive film I is 1
May be composed of three types of triple rutile structure compounds,
It may be composed of two or more triple rutile structural compounds.

The transparent conductive film I substantially made of such a triple rutile structure compound has practically sufficient conductivity and excellent visible light transmittance. The decrease in the visible light transmittance due to moisture is smaller than that of the ITO film.
The electron mobility is as high as about 40 cm ² / V · sec or more. The transparent conductive film I can be manufactured by various methods such as a sputtering method and a CVD method. However, since the composition can be controlled accurately and easily, the transparent conductive film I is manufactured by the method I of the present invention described later. Is preferred.

Next, the transparent conductive film II of the present invention will be described.
a cation that substantially comprises a triple rutile structure compound doped with at least one element selected from the group consisting of l, Sb, Ga, In, and Ge, and wherein the doping amount of the element is a constituent of the triple rutile structure compound It is characterized by being at most 20 at% with respect to the total amount of the elements. This transparent conductive film II may be made of one kind of triple rutile structure compound as in the case of the above-mentioned transparent conductive film I, or may be made of two or more kinds of triple rutile structure compounds. Further, similarly to the transparent conductive film I, a cation oxide or an amorphous component constituting the triple rutile structure compound may be contained, for example, in a proportion of 50 wt% or less, preferably 20 wt% or less.

Here, the reason why the doping amount of the element is limited to 20 at% or less as described above is that if it exceeds 20 at%, ion scattering occurs and the conductivity of the film becomes too low. The doping amount of the element is preferably 1 to 10 at%, particularly preferably 2 to 10 at%. The doping element is
It is preferable that the compound is not a basic constituent element of the triple rutile structure compound. For example, a triple rutile structure compound is Zn
When it is mainly composed of Sb ₂ O _6, it is preferable to dope at least one element selected from the group consisting of Sn, Al, In, Ga and Ge which is not a constituent element of the triple rutile structure compound.

A transparent conductive film substantially consisting of the above compound II
Has excellent visible light transmittance and is generally 4
It has an electron mobility of 0 cm ² / V · sec or more. The decrease in the visible light transmittance due to moisture is smaller than that of the ITO film. Further, the conductivity is substantially equal to or higher than that of the transparent conductive film I because the above-mentioned transparent conductive film I is substantially made of a compound in which an element having a valence of three or more is doped. This transparent conductive film II can also be manufactured by various methods, but for the same reason as the above-described transparent conductive film I, it is preferable to manufacture it by a method II of the present invention described later.

Next, the method I and the method II of the present invention will be described. First, the method I of the present invention will be described.
This method I is characterized in that as described above, a coating solution in which a predetermined amount of the basic starting material of the triple rutile structure compound is dissolved, the coating solution is applied to a substrate, fired, and then reduced. It is. Method I
The coating solution used in (1) usually contains a solvent and a solution stabilizer in addition to the above-mentioned basic starting material of the triple rutile structure compound.

Here, the kind of the basic starting material of the triple rutile structure compound is appropriately selected according to the intended triple rutile structure compound. Specific examples of the triple rutile structure compound include ZnSb ₂ O ₆ , ZnNb ₂ O ₆ , MgSb ₂ O ₆ ,
MgNb ₂ O _{6 and the} like. For example, when the target triple rutile structure compound is ZnSb ₂ O ₆ , a zinc compound and an antimony compound are used as basic starting materials by mixing Zn and Sb at a predetermined chemical ratio. Stoichiometric ratio (= 1: 2)
Weigh and use so that When the target triple rutile structure compound is MgNb ₂ O ₆ , a magnesium compound and a niobium compound are used as basic starting materials when the ratio of Mg and Nb is a predetermined stoichiometric ratio (= 1: 2). Weigh and use so that

Specific examples of the zinc (Zn) compound used as the basic starting material include zinc carboxylate such as zinc acetate, inorganic zinc compounds such as zinc chloride, zinc fluoride, and zinc iodide; Zinc alkoxides such as methoxide, zinc ethoxide, zinc propoxide and the like can be mentioned. Specific examples of the antimony (Sb) compound include antimony chloride (trivalent), antimony chloride (pentavalent), trimethoxyantimony, triethoxyantimony, tripropoxyantimony, and tributoxyantimony. Specific examples of magnesium (Mg) compounds include magnesium chloride, dimethoxy magnesium, diethoxy magnesium, di-i-propoxy magnesium, di-n
-Propoxy magnesium, di-i-butoxy magnesium, di-n-butoxy magnesium and the like.

Specific examples of the niobium (Nb) compound include niobium pentachloride, pentamethoxyniobium, pentaethoxyniobium, penta-i-propoxyniobium, penta-n-propoxyniobium, penta-i-butoxyniobium and penta-niobium. n-butoxyniobium, penta-sec-butoxyniobium and the like.

As a solvent for preparing the above-mentioned coating solution, alcohols such as methanol, ethanol, isopropyl alcohol, 2-methoxyethanol and 2-ethoxyethanol, and hydrocarbons such as toluene and benzene can be used. . Further, as a stabilizer of the solution, monoethanolamine, diethanolamine,
An alkanolamine such as triethanolamine can be used.

The preparation of the coating solution used in the method I comprises the steps of: providing a predetermined amount of the basic starting material of the triple rutile compound;
It can be performed by mixing a predetermined amount of a solvent and a stabilizer. The mixing order at this time is not particularly limited. Mixing may be stirring and mixing by a conventional method such as a stirrer, and heating may be performed at this time. The stirring time is 0.0
Preferred is 1 to 100 hours. If it is less than 0.01 hour, it is difficult to obtain a uniform transparent solution. On the other hand, if it exceeds 100 hours, the economy becomes poor. Particularly preferred stirring time is 0.1 to 100 hours. When heating during stirring, the heating temperature is preferably set to 100 ° C. or lower. 1
When the temperature exceeds 00 ° C., the solvent evaporates, and the solution concentration changes.

The concentration of the basic starting material of the triple rutile structure compound in the coating solution is 0.01 to 10 mol.
% Is preferable. If the content is less than 0.01 mol%, the film thickness per coating is small, and a large number of coatings are required to obtain a desired film thickness. On the other hand, if it exceeds 10 mol%, the film thickness becomes uneven during coating. A particularly preferred concentration is 0.1
-10 mol%.

[0020] The concentration of the stabilizer in the coating solution is preferably 0.01 to 10 mol%. 0.
If it is less than 01 mol%, it becomes difficult to dissolve the basic starting materials in a solvent. On the other hand, if it exceeds 10 mol%, carbon generated by decomposition of the stabilizer during firing will remain in the film even after firing, and the conductivity of the film will be reduced. Particularly preferred concentrations of the stabilizer are from 0.1 to 10 mol%.

In method I, the coating solution prepared as described above is applied to a substrate and then fired. Various substrates can be used depending on the application. Examples of the transparent substrate include alkali glass, non-alkali glass, quartz glass, and transparent polymer.
Note that the substrate may have an undercoat layer. Specific examples of the undercoat layer include ZnO, SiO ₂ , T
Examples include a thin film such as iO ₂ . Further, the coating method is not particularly limited, and various methods conventionally applied when producing a thin film from a solution can be used. Specific examples include a spray method, a dipping method, and a spin coating method.

As the firing method, methods such as normal pressure firing, vacuum firing, and pressure firing can be applied. Firing temperature is 5
00-1000 ° C is preferred. If the temperature is lower than 500 ° C., it is difficult to form a target triple rutile structure compound. on the other hand,
If it exceeds 1000 ° C., the film composition tends to change. A particularly preferred firing temperature is 600 to 900 ° C. The firing time depends on the firing temperature, but is preferably 0.01 to 10 hours. If the time is less than 0.01 hour, carbon generated by the decomposition of the solvent or the stabilizer remains in the film even after firing, and lowers the conductivity of the film. On the other hand, if it exceeds 10 hours, the economy becomes poor. A particularly preferred baking time is 0.1 to 10 hours.

If the desired film thickness cannot be obtained only by performing the operation of baking once after coating,
It is preferable that the operation of calcining after the application is performed a required number of times and then the main firing. The temperature for calcination is 3
00-1000 ° C is preferred. If the temperature is lower than 300 ° C., carbon generated by the decomposition of the solvent or the stabilizer remains in the film even after the calcination, and lowers the conductivity of the film. On the other hand, 1000 ° C
If it exceeds 3, the composition of the film changes and the desired triple rutile structure compound cannot be obtained. Particularly preferred calcination temperature is 300 to
600 ° C.

The calcination time varies depending on the calcination temperature, but is preferably 0.01 to 1 hour. In less than 0.01 hours,
Because the solvent or stabilizer will not fly away and remain
No matter how many times coating and calcination are repeated, the previously coated film will melt during the next coating and the film will not become thick. On the other hand, if it exceeds one hour, the economy becomes poor.

In the method I, a reduction treatment is performed after firing as described above. As a reduction method, reduction with a reducing gas, reduction with an inert gas, reduction by vacuum firing, or the like can be applied. Hydrogen gas as the reducing gas,
Steam or the like can be used. Further, as the inert gas, a nitrogen gas, an argon gas, a mixed gas of these gases and oxygen, or the like can be used.

The reduction temperature is preferably from 100 to 600 ° C.
If the temperature is lower than 100 ° C., it is difficult to perform a sufficient reduction.
On the other hand, when the temperature exceeds 600 ° C., the film composition tends to change. A particularly preferred reduction temperature is from 200 to 500C. The reduction time depends on the reduction temperature, but is preferably 0.01 to 10 hours. If the time is less than 0.01 hour, it is difficult to perform sufficient reduction. On the other hand, if it exceeds 10 hours, the economy becomes poor. Particularly preferred reduction times are from 0.1 to 10 hours.

The transparent conductive film I of the present invention, which can be produced by the above method I, has practically sufficient conductivity and excellent visible light transmittance. The decrease in the visible light transmittance due to moisture is smaller than that of the ITO film. The electron mobility is as high as about 40 cm ² / V · sec or more. This transparent conductive film I can be used as an electrode for various uses such as an electrode for a liquid crystal display element and an electrode for a solar cell.

Next, the method II of the present invention will be described.
As described above, the method II comprises, as described above, a predetermined amount of the basic starting material of the triple rutile structure compound, the Sn compound, the Al compound, and the Sb compound.
At least one doping material selected from the group consisting of a compound, a Ga compound, an In compound, and a Ge compound, so that the ratio of the doping element to the total amount of the cation elements constituting the triple rutile structure compound is 20 at% or less. A coating solution is prepared by dissolving the coating solution in a substrate, the coating solution is applied to a substrate, baked, and then subjected to a reduction treatment.

Here, the doping elements (Sn, Al, Sb,
The reason for limiting the ratio of (Ga, In, Ge) to 20 at% or less as described above is that if it exceeds 20 at%, the conductivity of the obtained film is too low due to ion scattering. By setting the ratio of the doping element to 20 at% or less, a transparent conductive film having conductivity equal to or higher than that of the transparent conductive film I can be obtained. Doping element ratio is 1 to 10
at% is preferable, and 2 to 10 at% is particularly preferable.

This method II comprises, in addition to the basic starting material of the triple rutile structure compound, at least one doping material selected from the group consisting of Sn compounds, Al compounds, Sb compounds, Ga compounds, In compounds and Ge compounds. Is different from the above-mentioned method I in that a predetermined amount is dissolved to prepare a coating solution. The other points, that is, the type of the basic starting material of the triple rutile structure compound, the method of preparing the coating solution, the type of the substrate, the firing method, and the reduction method are the same as those of the method I. The doping element is a transparent conductive film II
As described in the description, it is preferable that the compound is not a basic constituent element of the triple rutile structure compound. Further, the concentration of the total amount of the basic starting material of the triple rutile structure compound and the dope material in the coating solution is preferably 0.01 to 10 mol%, particularly preferably 0.1 to 10 mol% for the same reason as in the method I. Is preferred.

Specific examples of the Sn compound as the dope material used together with the basic starting material of the triple rutile structure compound in the method II include tin acetate (divalent), dimethoxytin, diethoxytin, dipropoxytin, dibutoxytin, tetramethoxytin, and the like. Examples thereof include tetraethoxytin, tetrapropoxytin, tetrabutoxytin, tin chloride (divalent), and tin chloride (tetravalent). Specific examples of the Al compound include aluminum chloride, trimethoxyaluminum, triethoxyaluminum, tripropoxyaluminum, and tributoxyaluminum.

Specific examples of the Sb compound include the same compounds as those exemplified as the basic starting material of the triple rutile structure compound in the description of Method I. Specific examples of the In compound include indium acetate, indium chloride, indium ethoxide, indium propoxide and the like.

Specific examples of the Ga compound include gallium chloride (trivalent), trimethoxygallium, triethoxygallium, tripropoxygallium, tributoxygallium and the like. Specific examples of the Ge compound include germanium chloride (tetravalent), tetramethoxygermanium, tetraethoxygermanium, tetrapropoxygermanium, tetrabutoxygermanium, and the like.

The transparent conductive film II of the present invention, which can be produced by the above-described method II, has excellent visible light transmittance and an electron mobility of about 40 cm ² / V · sec or more. ing. The decrease in the visible light transmittance due to moisture is smaller than that of the ITO film. Further, the conductivity is substantially equal to or higher than that of the transparent conductive film I because the above-mentioned transparent conductive film I is substantially made of a compound in which an element having a valence of three or more is doped. This transparent conductive film II
Can also be used as electrodes for various applications, such as electrodes for liquid crystal display elements and electrodes for solar cells.

[0035]

Embodiments of the present invention will be described below. Example 1 (Production Example of Transparent Conductive Film I by Method I) Anhydrous zinc acetate and triethoxyantimony (Sb (OC ₂ H ₅ ) ₃ ) as basic starting materials for a triple rutile structure compound
Using 2-methoxymethanol as a solvent, monoethanolamine as a stabilizer, and a quartz glass plate as a substrate, a transparent conductive film I was produced based on Method I as follows. First, 0.9 g of monoethanolamine and 3.3 g of triethoxyantimony were added to 24.9 g of 2-methoxymethanol and stirred and mixed for 10 minutes to obtain a transparent solution. While stirring this clear solution,
0.9 g of anhydrous zinc acetate was added to the transparent solution and stirred and mixed for 10 minutes to prepare a transparent and uniform coating solution. The molar ratio between Zn and Sb in this coating solution was Zn: Sb = 1: 2, and the concentration of the total amount of Zn and Sb was 0.5 mol / liter (4 mol%).

Next, a quartz glass plate (70 × 20 × 1.5 mm) is immersed in the obtained coating solution for dip coating (coating speed: 1.2 cm / min), and then 500 ° C. using an electric furnace. For 10 minutes. The above-mentioned operation of calcining after dip coating was repeated a total of 10 times, followed by main firing at 800 ° C. for 1 hour. Thereafter, vacuum (1 × 1) at 400 ° C. for 2 hours.
0 ^-2 torr) to obtain the intended transparent conductive film I.

X of the thus obtained transparent conductive film I
RD (X-ray diffraction, equipment used: Rotorflex RU-
200B (manufactured by Rigaku Corporation)), it was confirmed that the compound was substantially composed of a triple rutile structure compound (ZnSb ₂ O ₆ ). When the film thickness was measured from an electron micrograph of the cross section of the obtained transparent conductive film I, the film thickness was 2
00 nm. The electron mobility of the transparent conductive film I was measured by a four-terminal method. Table 1 shows the results. Also,
This transparent conductive film I was subjected to a moisture resistance test under the conditions of 40 ° C., 90% RH, and a test time of 1000 hours, and the visible light transmittance (test wavelength: 380 nm) before and after the test was compared. The results are also shown in Table 1.

Example 2 (Production Example of Transparent Conductive Film I by Method I) Anhydrous zinc acetate and pentaethoxy niobium were prepared as basic starting materials for a triple rutile structure compound. First, monoethanolamine 1 was added to 24 g of 2-methoxyethanol. .1 g and 3.8 g of pentaethoxyniobium were added and stirred and mixed for 10 minutes to obtain a transparent solution. Next, 1.1 g of anhydrous zinc acetate was added to the clear solution while stirring the clear solution, and the mixture was stirred and mixed for 10 minutes to prepare a clear and uniform coating solution. The molar ratio of Zn and Nb in this coating solution is Zn: Nb = 1: 2, and Zn and Nb
Was 0.5 mol / liter (4 mol%). After that, the target transparent conductive film I (film thickness 20
0 nm).

X of the thus obtained transparent conductive film I
When RD was measured in the same manner as in Example 1, it was confirmed that the RD was substantially composed of a triple rutile structure compound (ZnNb ₂ O ₆ ). The electron mobility of the transparent conductive film I was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. did. Table 1 shows the results.

Example 3 ( Example of Production of Transparent Conductive Film I by Method I) Diethoxymagnesium and triethoxyantimony were prepared as basic starting materials for a triple rutile structure compound. First, monoethanol was added to 25.5 g of 2-methoxyethanol. 1.0 g of the amine and 2.9 g of triethoxyantimony were added, and stirred and mixed for 10 minutes to obtain a clear solution. Next, while stirring the transparent solution, 0.5 g of diethoxymagnesium was added to the transparent solution, and the mixture was stirred and mixed for 10 minutes to prepare a transparent and uniform coating solution. The molar ratio of Mg to Sb in this coating solution is M
g: Sb = 1: 2, and the concentration of the combined amount of Mg and Sb was 0.5 mol / liter (4 mol%). After this,
A target transparent conductive film I (thickness: 200 nm) was obtained in the same manner as in Example 1 except that the main firing temperature was set to 900 ° C.

X of the thus obtained transparent conductive film I
When RD was measured in the same manner as in Example 1, it was confirmed that the RD was substantially composed of a triple rutile structure compound (MgSb ₂ O ₆ ). The electron mobility of the transparent conductive film I was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. did. Table 1 shows the results.

Example 4 (Production Example of Transparent Conductive Film I by Method I) Diethoxymagnesium and pentaethoxyniobium were prepared as basic starting materials of a triple rutile structure compound.
1.3 g of monoethanolamine and 4.5 g of pentaethoxyniobium were added to 23.3 g of 2-methoxyethanol, and stirred and mixed for 10 minutes to obtain a transparent solution. Next, while stirring the transparent solution, 0.8 g of diethoxymagnesium was added to the transparent solution, and the mixture was stirred and mixed for 10 minutes to prepare a transparent and uniform coating solution. The molar ratio of Mg to Nb in this coating solution is Mg: N
b = 1: 2, and the concentration of the combined amount of Mg and Nb is 0.5 m
ol / liter (4 mol%). Thereafter, the target transparent conductive film I (thickness: 200 nm) was obtained in the same manner as in Example 1 except that the main firing temperature was set to 900 ° C.

X of the thus obtained transparent conductive film I
When RD was measured in the same manner as in Example 1, it was confirmed that the RD was substantially composed of a triple rutile structure compound (MgNb ₂ O ₆ ). The electron mobility of the transparent conductive film I was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. did. Table 1 shows the results.

Comparative Example 1 ( Example of producing ITO thin film) First, 4.0 g of monoethanolamine and 3.8 g of indium acetate were added to 22.2 g of 2-methoxymethanol, and stirred and mixed for 10 minutes to prepare a transparent solution. did. Next, while stirring the transparent solution, Sn was added to the transparent solution.
0.1 g of (OC ₄ H ₉ ) ₂ was added, and the mixture was stirred and mixed for 10 minutes to prepare a transparent and uniform coating solution. The molar ratio of In to Sn in this coating solution is I
n: Sn = 95: 5, and the concentration of the total amount of In and Sn was 0.5 mol / liter (4 mol%). After this,
An ITO thin film (thickness: 200 nm) was obtained in the same manner as in Example 1 except that the main firing temperature was set to 500 ° C. The electron mobility of the ITO thin film thus obtained was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to determine the visible light transmittance before and after the test (test wavelength 380).
nm). Table 1 shows the results.

[0045]

[Table 1]

As is clear from Table 1, each of the transparent conductive films I obtained in Examples 1 to 4 was 80 cm ² / cm ² .
It has a high electron mobility of V seconds or more. Also,
The visible light transmittance of these transparent conductive films I shows no change before and after the moisture resistance test, or even if it does, a slight decrease after the test. This indicates that all of the transparent conductive films I obtained in Examples 1 to 4 have excellent moisture resistance. On the other hand, the electron mobility of the ITO thin film of Comparative Example 1 is as low as 20 cm ² / V · sec. In addition, the visible light transmittance is significantly reduced after the moisture resistance test, which indicates that the moisture resistance is inferior.

Example 5 ( Example of Production of Transparent Conductive Film II by Method II) Anhydrous zinc acetate and triethoxyantimony were used as basic starting materials for a triple rutile structure compound, and Sn compounds used together with the basic starting materials for a triple rutile structure compound. Dibutoxy tin, 2-methoxyethanol as a solvent,
Using a monoethanolamine as a stabilizer and a quartz glass plate as a substrate, a transparent conductive film II was produced as follows based on Method II.

First, using 2-methoxyethanol, monoethanolamine, triethoxyantimony, and anhydrous zinc acetate in the same manner as in Example 1, 30 g of a transparent and uniform solution (the coating solution of Example 1) Equivalent to)
Was prepared. Next, 0.16 g of dibutoxy tin was added to this solution.
Was added and stirred and mixed for 10 minutes to prepare a clear and uniform coating solution. The molar ratio of Zn and Sb in this coating solution is Zn: Sb = 1: 2, and the doping element S with respect to the total amount of the cation elements (Zn, Sb and Sn) constituting the target triple rutile structure compound
n ratio [Sn / (Zn + Sb + Sn)] × 100 is 4
at%. The concentration of the total amount of Zn, Sb and Sn in the coating solution is 0.5 mol / L (4 m
ol%). Thereafter, coating, baking and reduction treatment were performed in the same manner as in Example 1 to obtain a desired transparent conductive film II (200 nm in film thickness).

X of the thus obtained transparent conductive film II
As a result of measuring RD in the same manner as in Example 1, it was confirmed that the crystal structure of this transparent conductive film II was substantially the same as ZnSb ₂ O ₆ having a triple rutile structure. Also, there was no diffraction attributed to other structures, confirming that Sn was doped into the triple rutile structure. The electron mobility of the transparent conductive film II was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. Table 2 shows the results.

Example 6 (Production Example of Transparent Conductive Film II by Method II) Example 5 was repeated except that 0.15 g of an aluminum compound, tributoxyaluminum, was used in place of dibutoxytin, an Sn compound.
Coating solution {Zn: Sb = 1:
2, [Al / (Zn + Sb + Al)] × 100 = 4 at
%, The concentration of the total amount of Zn, Sb, and Al = 0.5 mol / liter (4 mol%)}, and using this coating solution, the transparent conductive film II (film thickness 2
00 nm).

X of the thus obtained transparent conductive film II
As a result of measuring RD in the same manner as in Example 1, it was confirmed that the crystal structure of this transparent conductive film II was substantially the same as ZnSb ₂ O ₆ having a triple rutile structure. Also, there was no diffraction attributed to other structures, confirming that Al was doped into the triple rutile structure. The electron mobility of the transparent conductive film II was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. Table 2 shows the results.

Example 7 ( Example of Production of Transparent Conductive Film II by Method II) Except that 0.11 g of gallium chloride (trivalent) of a Ga compound was used instead of dibutoxy tin of a Sn compound, the procedure was the same as in Example 5. Coating solution コ ー テ ィ ン グ Zn: Sb = 1: 2,
[Ga / (Zn + Sb + Ga)] × 100 = 4 at%, Z
The concentration of the total amount of n, Sb, and Ga = 0.5 mol / liter (4 mol%) was prepared, and the transparent conductive film II (film thickness: 200
nm).

X of the thus obtained transparent conductive film II
As a result of measuring RD in the same manner as in Example 1, it was confirmed that the crystal structure of this transparent conductive film II was substantially the same as ZnSb ₂ O ₆ having a triple rutile structure. Also, there was no diffraction attributed to other structures, confirming that Ga was doped into the triple rutile structure. The electron mobility of the transparent conductive film II was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. Table 2 shows the results.

Example 8 (Production Example of Transparent Conductive Film II by Method II) A coating solution was prepared in exactly the same manner as in Example 5 except that 0.15 g of a tetrapropoxygermanium Ge compound was used instead of dibutoxytin Sn compound. ｛Zn: Sb =
1: 2, [Ge / (Zn + Sb + Ge)] × 100 = 4
at%, the concentration of the total amount of Zn, Sb and Ge = 0.5 mol / l (4 mol%)}, and using this coating solution, the transparent conductive film II (film) 200 nm).

X of the thus obtained transparent conductive film II
As a result of measuring RD in the same manner as in Example 1, it was confirmed that the crystal structure of this transparent conductive film II was substantially the same as ZnSb ₂ O ₆ having a triple rutile structure. Also, there was no diffraction attributed to other structures, confirming that Ge was doped into the triple rutile structure. The electron mobility of the transparent conductive film II was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. Table 2 shows the results.

Example 9 ( Example of Production of Transparent Conductive Film II by Method II) A coating solution was prepared in the same manner as in Example 5, except that 0.11 g of indium acetate of an In compound was used instead of dibutoxytin of a Sn compound. Zn: Sb = 1: 2, [In
/ (Zn + Sb + In)] × 100 = 4 at%, Zn and S
concentration of the combined amount of b and In = 0.5 mol / liter (4 mol
%), And a transparent conductive film II (200 nm thick) was obtained in exactly the same manner as in Example 5 using this coating solution.

X of the thus obtained transparent conductive film II
As a result of measuring RD in the same manner as in Example 1, it was confirmed that the crystal structure of this transparent conductive film II was substantially the same as ZnSb ₂ O ₆ having a triple rutile structure. Also, there was no diffraction attributed to other structures, confirming that In was doped into the triple rutile structure. The electron mobility of the transparent conductive film II was measured in the same manner as in Example 1, and a moisture resistance test was performed in the same manner as in Example 1 to compare the visible light transmittance (test wavelength: 380 nm) before and after the test. Table 2 shows the results.

[0058]

[Table 2]

As is clear from Table 2, each of the transparent conductive films II obtained in Examples 5 to 9 was 79 cm ² /
It has a high electron mobility of V seconds or more. Also,
The visible light transmittance of these transparent conductive films II is not changed before and after the moisture resistance test, or even if it is recognized, it slightly decreases after the test. This indicates that all of the transparent conductive films II obtained in Examples 5 to 9 have excellent moisture resistance.

[0060]

As described above, the transparent conductive film of the present invention has better moisture resistance and higher electron mobility than the ITO film. Therefore, according to the present invention, it is possible to provide a transparent conductive film which is advantageous in obtaining an element or device having high durability and high electric field response.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI H01B 13/00 503 H01B 13/00 503B (56) References JP-A-5-238807 (JP, A) JP-A-6-96619 (JP, A) JP-A-6-290641 (JP, A) JP-A-6-191844 (JP, A) JP-A-1-167233 (JP, A) JP-A-57-171678 (JP, A) Hiroshi, Search for New Transparent Conductive Materials, New Ceramics, Vol. 5, No. 12, pp. 63-68, 1992 (58) Fields surveyed (Int. Cl. ⁷ , DB name) H01B 5/00-5/16 CA (STN) JICST file (JOIS) REGISTRY (STN)

Claims (6)

(57) [Claims] (1) a compound substantially consisting of a triple rutile structure compound;
Ri, transparent conductive film electron mobility is characterized by Der Rukoto more than 40cm ² / V · sec. 2. The triple rutile structure compound is ZnSb ₂ O.
₆ , ZnNb ₂ O ₆ , MgSb ₂ O ₆ and MgNb ₂
Is at least one compound selected from the group consisting of O _6, transparent conductive film according to claim 1. 3. Sn, Al, Sb, Ga, In and G
e, which consists essentially of a triple rutile structure compound doped with at least one element selected from the group consisting of e, wherein the doping amount of the element is 20 atm with respect to the total amount of the cation elements constituting the triple rutile structure compound. % Or less. 4. The transparent conductive film according to claim 3 , wherein the electron mobility is 40 cm ² / V · sec or more. 5. A method for preparing a transparent conductive film, comprising: preparing a coating solution in which a predetermined amount of a basic starting material of a triple rutile structure compound is dissolved; applying the coating solution to a substrate; Production method. 6. A predetermined amount of a basic starting material of a triple rutile structure compound, and a Sn compound, an Al compound, an Sb compound, and a Ga compound.
At least one doping material selected from the group consisting of a compound, an In compound and a Ge compound is dissolved so that the ratio of the doping element to the total amount of the cation elements constituting the triple rutile structure compound is 20 at% or less. A method for producing a transparent conductive film, comprising preparing a coating solution, applying the coating solution to a substrate, baking the substrate, and subjecting the substrate to a reduction treatment.