JPH09152940A - Touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the input accuracy of a touch panel. SOLUTION: At least one of transparent electrode films respectively formed on two transparent electrode substrates constituting the touch panel consists of an oxide film containing at least either one of indium In and a tin Sn, at least one kind of metallic element selected from an element group consisting of a titanium Ti, silicon Si, nickel Ni, iridium Ir, rhodium Rh, cerium Ce, zirconium Zr, thallium Tl, hafnium Hf, magnesium Mg, alminium Al, tantalum Ta, cobalt Co, lead Pb, germanium Ge, chrome Cr, and zinc Zn and oxygen O as constitutional elements and having 2.2 to 40at.% of [atom rate (total metallic atoms) of all metallic elements]/[(In or Sn)+(all metallic atoms)] and the film thickness and specific resistance of the transparent electrode film are included in a rectangular range having points A to D as vertexes.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a touch panel.

[0002]

2. Description of the Related Art In recent years, as one of input devices for inputting data to a computer main body (main storage device) such as a personal computer, a word processor, and an electronic notebook, a load is simply applied to an input surface with a finger or a pen. A touch panel (including a touch screen; the same applies hereinafter) that can input data only by itself has been widely used. This touch panel has various principles, and one of them is a resistive touch panel. The resistance film type touch panel is roughly classified into an analog type and a digital type. Recently, the analog type is being adopted with the improvement of the detection sensitivity of the input position.

In an analog type touch panel, two transparent electrode substrates each having a transparent base material and a transparent electrode film (resistive film) formed in a flat film shape on the transparent base material are provided. Are arranged so as to face each other while being kept at a predetermined interval by a spacer or the like, and one of the two transparent electrode substrates is located on the input surface side. Each of these transparent electrode films is formed so that the transparent electrode films are electrically connected to each other when a load is applied to the transparent electrode substrate from the outside of the transparent electrode substrate located on the input surface side. Are electrically connected to a predetermined drive circuit via electrode terminals and lead wires (takeout electrodes) provided at predetermined positions. Each of the transparent electrode films is also electrically connected to coordinate detecting means using a comparison circuit, a microprocessor, an analog / digital converter, and the like.

In this analog type touch panel, when a load is applied from the outside of the transparent electrode substrate located on the input surface side and the transparent electrode films become conductive, a predetermined end of one of the transparent electrode films is formed. A circuit is formed such that a current flows from the first transparent electrode film to a predetermined end of the other transparent electrode film through a portion where the above-described conduction occurs. Then, the electric resistance value in this circuit changes in accordance with the position coordinates of the place where the conduction occurs, that is, the place where the load is applied, so based on the change in the electric resistance value,
The position coordinates of the place where the load is applied are detected by the coordinate detecting means. Therefore, the transparent electrode film used in the analog type touch panel is required to have higher electric resistance and superior surface resistance uniformity than the transparent electrode film used in the digital type touch panel. It

By the way, in recent years, with respect to the resistance film type touch panel, particularly the analog type touch panel, there has been a growing demand for higher precision of the input accuracy. It is desired to use a transparent electrode film which is

Conventionally, an ITO film formed by a physical vapor deposition method is often used as a transparent electrode film, but the ITO film is a transparent conductive film having a specific resistance of less than 10 ⁻³ Ω · cm. Therefore, in order to obtain an analog type touch panel in which the input accuracy is improved by using the ITO film as the transparent electrode film, it is necessary to make the thickness of the ITO film as thin as about 10 nm. However, such an extremely thin thin film is not practically usable because it does not go out of the region of an island structure (see "Basic Technology of Thin Film" (The University of Tokyo Press), pp. 90-91). For this reason, especially for the transparent electrode film of the analog type touch panel, development of a new high electric resistance film replacing the ITO film is desired.

As a film having a higher electric resistance than the ITO film,
A high resistance conductive film formed of SnO ₂ containing 1 to 20 mol% of at least one component of Ta ₂ O ₂ , TiO ₂ or ZrO ₂ (see JP-A-57-109206),
SiO ₂ , TiO ₂ , in a transparent conductive metal oxide thin film,
A film obtained by adding at least one metal oxide selected from the group consisting of Al ₂ O ₃ , ZrO ₂ , MgO, and ZnO in an atomic composition ratio of 0.5 to 2% (see JP-A-6-349338) is obtained. Are known.

[0008]

However, since the high resistance conductive film disclosed in Japanese Patent Laid-Open No. 57-109206 is very high in surface resistance of 10 ⁶ Ω / □ or more, it is used for a touch panel. It is not practical as an electrode film.
Further, since this high resistance conductive film is formed by a wet method, the base material is heated to 400 ° C. in the drying step.
It is necessary to heat above, and therefore, there is a drawback that the material of the base material is significantly limited.

On the other hand, the film specifically disclosed in the example of JP-A-6-349338 has a high surface resistance of 500 to 700 Ω / □ at a film thickness of 17 nm and is durable. Since it is also excellent, it is suitable as a transparent electrode film of an analog type touch panel. However, as described above, with the recent increasing demand for higher precision of the input accuracy of the analog type touch panel, it is desired that the transparent electrode film of the touch panel has a surface resistance of approximately 800Ω / □ or more. Has reached. That is, the above-mentioned JP-A-6-3493.
No. 38, the surface resistance 500 specifically disclosed.
In recent years, the demand for higher precision of the input accuracy of an analog type touch panel has become so severe that a film of 700 Ω / □ can no longer follow it.

An object of the present invention is to provide a touch panel with improved input accuracy.

[0011]

A touch panel according to the present invention which achieves the above object comprises two transparent electrode substrates having a transparent electrode film formed in a predetermined pattern. A touch panel that is arranged at a predetermined interval with the transparent electrode films facing each other, and the transparent electrode films are electrically connected to each other when a load is applied to the transparent electrode substrate from the outside of one of the transparent electrode substrates. , The above 2
At least one of the transparent electrode films formed on each of the transparent electrode substrates is at least one of indium (In) and tin (Sn) and titanium (Ti), silicon (Si), nickel (Ni). ), Iridium (I
r), rhodium (Rh), cerium (Ce), zirconium (Zr), thallium (Tl), hafnium (H
f), magnesium (Mg), aluminum (Al),
Tantalum (Ta), cobalt (Co), lead (Pb), germanium (Ge), chromium (Cr) and zinc (Z
n), at least one metal element selected from the group consisting of n) and oxygen (O) as constituent elements, and the atomic ratio of the total amount of the metal elements (total metal atoms) / [(In or Sn) + (total Metal atom)] is 2.2 to 40 at%, and the film thickness and specific resistance of the transparent electrode film have points A, B, C and D shown in FIG. It is characterized by being within the range of a quadrangle (hereinafter, this touch panel is referred to as "touch panel I").

Further, another touch panel of the present invention which achieves the above object is provided with two transparent electrode substrates having a transparent electrode film formed in a predetermined pattern, and the two transparent electrode substrates are the transparent electrodes. Electrode films are arranged at a predetermined interval so as to face each other, a touch panel in which the transparent electrode films are conducted when a load is applied to the transparent electrode substrate from the outside of one of the transparent electrode substrates, At least one of the transparent electrode films formed on each of the two transparent electrode substrates has indium (In), titanium (Ti), zinc (Zn), and oxygen (O) as constituent elements, and the titanium ( The atomic ratio (Ti + Zn) / (In + Ti + Zn) of the total amount of Ti) and the zinc (Zn) is 2.
It is composed of an oxide film of 2 to 50 at%, and the film thickness and the specific resistance of the transparent electrode film are point A shown in FIG.
It is characterized by being within the range of a quadrangle having B, C and D as vertices (hereinafter, this touch panel is referred to as "touch panel II").

[0013]

Embodiments of the present invention will be described below in detail. First, the touch panel I of the present invention will be described. The feature of the touch panel I is that, as described above, at least the transparent electrode film formed on each of the two transparent electrode substrates forming the touch panel I. One is made of an oxide film having a specific composition, and the film thickness and specific resistance of the transparent electrode film made of this oxide film are
Since it is located at a point within the range of a quadrangle having the vertices of points A, B, C, and D shown in FIG. The transparent electrode film made of the specific oxide film will be described. In addition,
The line segment AB in FIG. 1 shows the relationship between the film thickness and the specific resistance of an oxide film having a surface resistance of 10 kΩ / □, and the line segment CD represents the oxide film having a surface resistance of 800 Ω / □. The relationship between the film thickness and the specific resistance is shown.

As described above, the transparent electrode film is made of either indium (In) or tin (Sn), titanium (Ti), silicon (Si), nickel (Ni),
Iridium (Ir), Rhodium (Rh), Cerium (C
e), zirconium (Zr), thallium (Tl), hafnium (Hf), magnesium (Mg), aluminum (Al), tantalum (Ta), cobalt (Co), lead (Pb), germanium (Ge), chromium (chrome). Cr) and zinc (Zn), and at least one metal element selected from the group consisting of an oxide film containing oxygen (O) as a constituent element. The oxide film is composed of only the above-mentioned constituent elements, except for unavoidable contaminants in the manufacturing process.

Then, the atomic ratio of the total amount of the metal elements in the above oxide film (total metal atoms) / [(In or S
n) + (all metal atoms)] is 2.2 to 40 as described above.
at%. Here, "all metal atoms" in the formula representing the atomic ratio of the total amount of the metal elements, means the total number of atoms (relative value) for the metal elements selected from the above group,
“In or Sn” is the number of atoms (relative value) of the element that is a constituent element of the oxide of In and Sn.
Means

The reason why the lower limit of the atomic ratio of the total amount of the metal elements in the touch panel I is limited to 2.2 at% is that the oxide film having the atomic ratio of less than 2.2 at% has a specific resistance of 9.
Since it is less than 6 × 10 ⁻⁴ Ω · cm, the surface resistance at the minimum film thickness (about 12 nm) that can be practically used as a thin film is 800.
This is because it becomes less than Ω / □, and it becomes difficult to obtain an analog type touch panel with improved input accuracy. Also,
The reason why the upper limit of the atomic ratio of the total amount of the metal elements in the touch panel I is limited to 40 at% is that the atomic ratio is 40%.
If the oxide film exceeds at%, the specific resistance is 2.0 × 10 ^-1 Ω ・
Since the thickness exceeds 200 cm, the surface resistance exceeds 10 kΩ / □ even when the film thickness is 200 nm, and the resistance value distribution becomes large with such a high surface resistance transparent electrode film, resulting in an analog touch panel with improved input accuracy. Because it will be difficult to obtain.

However, among the oxide films composed of the above constituent elements, in the oxide film in which the constituent elements other than indium (In) and oxygen (O) are titanium (Ti) and zinc (Zn), Ti and Since both Zn have semiconducting properties, the atomic ratio of the total amount of these elements (Ti
+ Zn) / (In + Ti + Zn) increases, the electric resistance of the oxide film increases slowly. Therefore, as will be described later, in an oxide film containing indium (In), titanium (Ti), zinc (Zn) and oxygen (O) as constituent elements, the atomic ratio of the total amount of metal elements selected from the above-mentioned group. That is, the upper limit of the atomic ratio (Ti + Zn) / (In + Ti + Zn) of the total amount of titanium (Ti) and zinc (Zn) can be exceptionally increased to 50 at%.

The oxide film having the above-mentioned composition is (1) amorphous, (2) if it can form a transparent electrode film having a film thickness and a specific resistance within the region shown in FIG. ) A mixture of any one of indium oxide and tin oxide and an oxide of the above metal element (crystalline except for mixed crystals),
(3) a mixed crystal of any one of indium oxide and tin oxide and the oxide of the above metal element, (4) a mixture of the mixed crystal of the above (3) and the oxide of the above metal element, It may consist of either.

Each of the oxide films of (1) to (4) above has 2
Since the visible light transmittance at a thickness of 00 nm is about 85% or more, by setting the thickness at 200 nm or less, it can be suitably used as a transparent electrode film of a touch panel. When the film thickness of the oxide film exceeds 200 nm, light absorption in the visible region becomes large, and thus the touch panel using such an oxide film as the electrode film has a dark input surface and is difficult to see. On the other hand, if the thickness of the oxide film is 12
If it is less than nm, it becomes difficult to form a transparent electrode film that can be put to practical use. Therefore, in the touch panel I, as shown in FIG.
As shown in, the thickness of the transparent electrode film made of the above-mentioned oxide film is set to 12 to 200 nm. When used as a transparent electrode film of an analog type touch panel, the oxide film (transparent electrode film) preferably has a thickness of 12 to 100 nm, and particularly preferably 15 to 50 nm.

The surface resistance of the oxide film (transparent electrode film) described above can be appropriately adjusted by changing its composition and film thickness. In the touch panel I, the film thickness and surface of the oxide film are used. The value of the specific resistance of the oxide film (transparent electrode film), which can be obtained by multiplying by the resistance, is the value in the region shown in FIG. If the specific resistance value deviates from the region shown in FIG. 1, it becomes difficult to obtain an analog type touch panel with improved input accuracy. The surface resistance of the oxide film (transparent electrode film) is preferably 1000 to 5000 Ω / □ when the oxide film is used as a transparent electrode film of an analog type touch panel.

Among the oxide films having the above-mentioned composition, film thickness and specific resistance, indium (In) is preferable from the viewpoint that it is easy to obtain a transparent electrode film having high stability of electric resistance with time.
And at least one metal element selected from the group consisting of titanium (Ti), silicon (Si), zirconium (Zr), aluminum (Al) and zinc (Zn), and oxygen (O) as constituent elements. , An oxide film in which the atomic ratio (total metal atoms) / [(In) + (total metal atoms)] of the total amount of the metal elements is 2.5 to 30 at%, and indium (I
n) and titanium (Ti) and / or zinc (Zn)
And an oxide film containing oxygen (O) as a constituent element are preferable.

In the touch panel I, as described above, at least one of the transparent electrode films formed on each of the two transparent electrode substrates forming the touch panel I has the above-mentioned composition, film thickness and It is composed of an oxide film having a specific resistance. A transparent electrode substrate having a transparent electrode film made of this oxide film is formed on a desired transparent base material by sputtering, plasma CVD, spray pyrolysis,
It can be obtained by forming the above oxide film by a method such as a sol-gel method or an ion plating method.

The transparent substrate used at this time may be any substrate having a visible light transmittance of approximately 70% or more, and specific examples thereof include polycarbonate resin, polyarylate resin,
Polyester resins such as polyethylene terephthalate, polyether sulfone resins, amorphous polyolefin resins, polystyrene resins, transparent polymer materials such as acrylic resins, soda lime glass, lead glass, borosilicate glass,
Examples thereof include film-like materials, sheet-like materials and plate-like materials made of glass such as alkali-free glass. Among these,
From the viewpoint of flexibility and cost, polyethylene terephthalate is preferable.

If desired, a gas barrier layer, a hard coat layer, an antireflection layer or the like may be provided on one side or both sides of the transparent substrate. Specific examples of the gas barrier layer include those made of ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyacrylonitrile, polyvinylidene chloride, polyvinylidene fluoride, and the like. Specific examples of the hard coat layer include those made of titanium-based or silica-based hard coating agents, polymeric materials such as polymethylmethacrylate, and polyphosphazene. Specific examples of the antireflection layer include low refractive index polymers such as fluorine-based acrylic polymers, inorganic fluorides such as MgF ₂ and CaF ₂ , TiO ₂ , SiO ₂ , and Zn.
Examples thereof include inorganic oxides such as O, Bi ₂ O ₃ and Al ₂ O ₃ , and those composed of a laminated body thereof.

In forming the transparent electrode film made of the above-mentioned oxide film on the above-mentioned transparent base material, various methods can be applied as described above, but the uniformity and the adhesion to the transparent base material From the viewpoint of obtaining a transparent electrode film having excellent properties, it is preferable to apply a sputtering method (including a reactive sputtering method). As the sputtering target, it is preferable to use a sintered body target made of an oxide according to the composition of the target transparent electrode film. Here, the “sintered body target made of an oxide corresponding to the composition of the target transparent electrode film” means a sintered body target made of an oxide of which the transparent electrode film of the target composition can be obtained. Means The composition of the sintered target is appropriately selected according to the sputtering rate and the composition of the target transparent electrode film.

In the above-mentioned sintered body target, for example, for each element other than oxygen (O) among the elements constituting the desired transparent electrode film, a predetermined amount of an oxide or a compound which becomes an oxide by firing is used. They can be obtained by mixing them one by one, calcining the mixture, crushing it, and then molding and sintering. For example, when the target transparent electrode film has indium (In), zinc (Zn), titanium (Ti) and oxygen (O) as constituent elements, the target sintering is performed as follows. You can get a body target.

First, indium oxide or a compound that becomes indium oxide by firing (eg, indium chloride, indium nitrate, indium acetate, indium hydroxide, indium alkoxide) and zinc oxide or a compound that becomes zinc oxide by firing (eg, zinc chloride). , Zinc nitrate,
Zinc acetate, zinc hydroxide, zinc alkoxide, etc.) and titanium oxide or a compound that becomes titanium oxide by firing (eg, titanium chloride, titanium nitrate, titanium sulfate, etc.) are weighed and mixed in predetermined amounts. The resulting mixture is then 5
It is calcined at 00 to 1200 ° C.
Grind with a roll mill, pearl mill, jet mill, etc.,
A powder having a particle diameter in the range of 0.01 to 1.0 μm and a uniform particle diameter is obtained. Prior to pulverization of the calcined product, the calcined product may be subjected to a reduction treatment at 100 to 800 ° C. If necessary, the powder may be further calcined and pulverized a desired number of times. Then, the obtained powder is pressure-molded into a desired shape to form a molded product at 800 to 17
Sinter at 00 ° C. At this time, polyvinyl alcohol, methyl cellulose, polywax, oleic acid or the like may be used as a sintering aid, if necessary. By obtaining a sintered body in this way, a target sintered body target can be obtained.

Sputtering using the above-mentioned sintered body target can be performed by RF sputtering, DC sputtering, etc., but from the viewpoint of productivity and film characteristics of the obtained oxide film, it is industrially general. DC sputtering is preferred. An example of DC sputtering conditions is as follows.

That is, the sputtering atmosphere is an inert gas such as argon gas or a mixed gas of an inert gas and oxygen gas, and the atmospheric pressure (sputtering pressure) during sputtering is used.
Is about 1 × 10 ⁻² Pa to 5 Pa, and the target applied voltage (discharge voltage) is less than 1000V. If the atmospheric pressure during sputtering (sputtering pressure) is less than 1 × 10 ^-2 Pa, plasma stability is poor, and if it exceeds 5 Pa, the adhesion of the resulting oxide film to the substrate is poor. Further, when the target applied voltage (discharge voltage) is 1000 V or more, the oxide film is damaged by the plasma, so that the oxide film having the desired electrical characteristics cannot be obtained, or the target is easily broken. . Target applied voltage (discharge voltage)
Is preferably less than 800V, more preferably 500
It is less than V. In order to obtain a high-quality oxide film, it is preferable to make the target applied voltage (discharge voltage) as low as possible, but if it is extremely low, there arises a problem of productivity. Therefore, the optimum value of the target applied voltage (discharge voltage) is appropriately selected in consideration of the required quality and productivity of the transparent electrode film. In addition, the substrate temperature during film formation (temperature of the transparent base material) is appropriately selected within a temperature range in which the transparent base material does not deform or deteriorate due to heat, depending on the heat resistance of the transparent base material.

The shape of the transparent electrode film made of the above oxide film is appropriately selected according to the type of touch panel using the transparent electrode film. For example, when used for a digital type touch panel, a desired parallel stripe pattern is formed by using a predetermined mask during film formation or by performing a predetermined patterning after film formation. When used for an analog type touch panel, a single flat film is formed by using a predetermined mask as needed during film formation or by performing predetermined patterning as necessary after film formation. Is formed.

In the touch panel I, at least one of the transparent electrode films formed on each of the two transparent electrode substrates forming the touch panel I may be made of the above oxide film. Only one transparent electrode substrate having a transparent electrode film formed of the above-mentioned oxide film is used, and another transparent electrode substrate having a transparent electrode film formed of a film other than the above-mentioned oxide film is used. When the touch panel I is used as the above, the above-mentioned “transparent electrode film made of a film other than the above-mentioned oxide film” is an ITO film, a tin oxide film, or the like and is excellent in transparency and stability of electric resistance with time. It is preferable to use those which are present. In the case of obtaining an analog type touch panel with high input accuracy, it is preferable to use a transparent electrode substrate having the above-mentioned transparent electrode film made of an oxide film, as each of the two transparent electrode substrates.

The touch panel I uses, as at least one of the two transparent electrode substrates forming the touch panel I, a transparent electrode substrate having a transparent electrode film formed of the above oxide film, It is constructed in the same way as a conventional touch panel. At this time, the two transparent electrode substrates are arranged so that the transparent electrode films face each other while being kept at a predetermined interval by a spacer or the like, and one of these transparent electrode substrates is located on the input surface side. Each of these transparent electrode films is connected to the transparent electrode film so that the transparent electrode films conduct when a load is applied to the transparent electrode substrate from the outside of the transparent electrode substrate located on the input surface side. Are electrically connected to a predetermined drive circuit through electrode terminals and lead wires (extraction electrodes) provided at predetermined positions. Each of the transparent electrode films is also electrically connected to coordinate detection means using a comparison circuit, a microprocessor, an analog / digital converter, and the like. The touch panel I configured as described above is preferably a resistive film type touch panel, and particularly preferably an analog type touch panel.

The principle of detecting the data input position in the touch panel I of the present invention is the same as the conventional one, but at least one of the two transparent electrode substrates constituting the touch panel I has a surface resistance of 800Ω / □. The transparent electrode film is formed by the above-mentioned oxide film having a high value of 10 kΩ / □. For this reason, in the touch panel I of the present invention, it is difficult for data to be mistakenly detected during coordinate detection, and reliable data input can be stably performed.

Next, the touch panel II of the present invention will be described. As described above, the touch panel II of the present invention also has
At least one of the transparent electrode films formed on each of the two transparent electrode substrates forming the touch panel II is made of an oxide film having a specific composition, and the transparent electrode film made of the oxide film is formed. Since the film thickness and the specific resistance are within the region shown in FIG. 1, the transparent electrode film made of the specific oxide film will be described first.

As described above, this transparent electrode film is an oxide film containing indium (In), titanium (Ti), zinc (Zn) and oxygen (O) as constituent elements. The oxide film is composed of only the above-mentioned constituent elements, except for unavoidable contaminants in the manufacturing process. The atomic ratio (Ti + Zn) / (In + Ti + Zn) of the total amount of titanium (Ti) and zinc (Zn) in the oxide film is 2.2 to 50 at% as described above.

On the touch panel II, the titanium (T
The atomic ratio of the total amount of i) and zinc (Zn) is 2.2 to 50.
The reason for limiting to at% is that when the atomic ratio is out of the above range, it becomes difficult to obtain an oxide film in which the relationship between the film thickness and the specific resistance is within the region shown in FIG.

Among the oxide films having the above composition, the atomic ratio of the total amount of titanium (Ti) and zinc (Zn) is 10.
An oxide film having an atomic ratio In / (In + Ti + Zn) of indium of 50 to 90 at%, an atomic ratio Ti / (In + Ti + Zn) of titanium of 1 to 20 at%,
The atomic ratio of zinc Zn / (In + Ti + Zn) is 10 to 30.
At% oxide film is titanium (Ti) and zinc (Z
By adjusting each content (atomic ratio) of n), there is an advantage that a transparent electrode film having a desired surface resistance value can be easily formed with high accuracy.

The above oxide film is (1) amorphous, (2) indium oxide, as long as it can form a transparent electrode film having a film thickness and a specific resistance within the region shown in FIG. A mixture of an oxide, titanium oxide and zinc oxide (crystalline except for mixed crystals), (3) mixed crystal of indium oxide, titanium oxide and zinc oxide, (4) above ( It may consist of a mixture of the mixed crystal of 3) and titanium oxide and / or zinc oxide.

All the oxide films of (1) to (4) above are
The visible light transmittance at a thickness of 00 nm is approximately 85% or more. Therefore, also in the touch panel II, for the same reason as the above-mentioned reason in the touch panel I of the present invention,
As shown in FIG. 1, the film thickness of the transparent electrode film made of the above oxide film is set to 12 to 200 nm. When used as a transparent electrode film of an analog type touch panel, the oxide film (transparent electrode film) preferably has a thickness of 12 to 100 nm, particularly preferably 15 to 50 nm.

The surface resistance of the oxide film (transparent electrode film) described above can be appropriately adjusted by changing its composition and film thickness. In the touch panel II, the film thickness and surface of the oxide film are also adjusted. The value of the specific resistance of the oxide film (transparent electrode film), which can be obtained by multiplying by the resistance, is the same as the value in the region shown in FIG. To do. The surface resistance of the oxide film (transparent electrode film) is similar to that of the oxide film in the touch panel I of the present invention described above when the oxide film is used as a transparent electrode film of an analog type touch panel. It is preferably set to 1000 to 5000 Ω / □.

In the touch panel II, at least one of the transparent electrode films formed on each of the two transparent electrode substrates constituting the touch panel II is an oxide having the above-mentioned composition, film thickness and specific resistance. Since the oxide film can be manufactured in the same manner as the oxide film in the touch panel I of the present invention described above, the description of the manufacturing method is omitted here. Further, since the constituent members of the touch panel II other than the oxide film are the same as those of the touch panel I of the present invention described above, the description thereof will be omitted here. The touch panel II of the present invention described above is also preferably a resistance film type touch panel as in the touch panel I of the present invention described above, and particularly preferably an analog type touch panel.

The principle of detecting the data input position in the touch panel II of the present invention is the same as the conventional one, but at least one of the two transparent electrode substrates constituting the touch panel II is the touch panel I of the present invention described above. Similarly, the transparent electrode film is formed of an oxide film having a high surface resistance of 800 Ω / □ to 10 kΩ / □. Therefore, in the touch panel II of the present invention as well, it is unlikely that data will be mistakenly detected when coordinates are detected, and reliable data input can be performed stably. In addition, among the above oxide films, the oxide film in which the atomic ratio of the total amount of titanium (Ti) and zinc (Zn) is 10 to 50 at% accurately forms a transparent electrode film having a target surface resistance value. Since the touch panel II of the present invention including the transparent electrode film made of the oxide film is easy to obtain, it is easy to obtain the target input accuracy.

[0043]

Embodiments of the present invention will be described below. Examples 1 to 72 (1) Preparation of transparent electrode substrate Long product of biaxially stretched polyethylene terephthalate film as transparent substrate (size: 300 mm x 10 m, thickness 1
25 μm. Hereinafter referred to as PET roll. ) Is used as a sputtering target and is made of an oxide having an atomic composition ratio (excluding oxygen) shown in Table 1 or 2 below (size: 5 inches × 15 inches × 5 mm thickness).
Using, the oxide film having the atomic composition ratio (excluding oxygen) shown in Table 1 or Table 2 below was formed in the following manner. The atomic composition ratio of the oxide film was determined by induction plasma emission spectroscopy (ICP).

First, the PET roll was mounted on a continuous traveling type DC magnetron sputtering device, and the inside of the vacuum chamber was set to 5 ×.
The pressure was reduced to 10 ⁻³ Pa or less. Next, argon gas (purity 99.99%) was introduced so that the pressure in the vacuum chamber was 2 × 10 ⁻¹ Pa, and the sputtering output was 1.6 W / cm.
² (target applied voltage is 400V)
Presputtering was performed by setting the temperature to 0 ° C. After the pre-sputtering, a mixed gas of argon gas and oxygen gas (volume ratio of argon gas and oxygen gas = 97: 3) was kept at a vacuum chamber pressure of 2 × 10 while maintaining the sputtering output and the substrate temperature at the above values. -Introduced so that it becomes ¹ Pa, 1
An oxide film (transparent electrode film) was formed on one side of the PET roll at a running speed of 00 cm / min.

From the PET roll with the oxide film (transparent electrode film) obtained as described above, the size in plan view was 16 ×
A transparent electrode substrate was obtained by cutting out a 16 cm PET film with an oxide film.

For each of the obtained transparent electrode substrates, the film thickness, surface resistance, standard deviation of surface resistance and specific resistance of the oxide film (transparent electrode film) constituting the transparent electrode substrate were determined. In addition, for each transparent electrode substrate, a wavelength of 5
The transmittance of 50 nm light was determined. The results are shown in Table 3 or Table 4 below.

The film thickness is obtained by separately forming a film under the above conditions using a slide glass for measurement.
It was measured by a stylus method using DEKTAK3030 manufactured by Sloan. Surface resistance is Loresta F manufactured by Mitsubishi Petrochemical Co., Ltd.
It was measured by a four-terminal method using P, and the standard deviation of the surface resistance was determined from the surface resistance of these films by forming the film under the above conditions five times for each example. The specific resistance was calculated by multiplying the surface resistance measured at the central portion of the oxide film in plan view by the film thickness of the oxide film formed on the slide glass (see “Measurement / evaluation of thin film material”). (Technical Information Association, pp. 114-115). The light transmittance of the transparent electrode substrate is UV- manufactured by Shimadzu Corporation.
It was measured using 3100.

Furthermore, after the transparent electrode substrate obtained in each of the examples was left standing in air at 120 ° C. for 300 hours, the surface resistance R of the oxide film (transparent electrode film) forming the transparent electrode substrate. Was measured in the same manner as above, and the ratio R / R ₀ to the surface resistance R ₀ immediately after film formation (shown in the column of surface resistance in Table 3 or Table 4 below) was determined. These results are also shown in Table 3 or Table 4 below.

As shown in Table 3 or 4 below, each oxide film formed in Examples 1 to 72 has a high surface resistance of 840 to 8990 Ω / □ and a high resistance. As can be seen from the standard deviation of surface resistance, it can be obtained with good reproducibility. Further, as can be seen from the value of R / R ₀ , it is also excellent in heat resistance.
2,7,11,36,37,39,43,49,50,
The heat resistance of each oxide film formed by 58 and 65 is high.
From these, it is understood that the transparent electrode substrate obtained in each example has excellent characteristics suitable as a transparent electrode substrate of a touch panel, particularly an analog type touch panel.

(2) Fabrication of touch panel From each PET roll with an oxide film (transparent electrode film) obtained in (1) above, a PET film with an oxide film having a size of 16 × 16 cm in plan view was prepared. Two pieces were cut out, and using these two transparent electrode substrates, an analog type touch panel, the outline of which is shown in FIG. 2, was produced in each example as follows.

First, a pair of electrode terminals 3a having a width of 3 mm are formed on a pair of edge portions of the oxide film (transparent electrode film) 2 constituting one transparent electrode substrate 1 which face each other. 3b silver paste (D-550 manufactured by Fujikura Kasei Co., Ltd.)
Provided by each. The other transparent electrode substrate 5
Similarly, on the pair of edge portions facing each other in the oxide film (transparent electrode film) 6 forming the
Electrode terminals 7a and 7b each having a strip shape of m are provided.

Next, in the transparent electrode substrate 1 and the transparent electrode substrate 5, the oxide films (transparent electrode films) 2 and 6 are opposed to each other, and the electrode terminals 3a and 3b are connected and the electrode terminals 7a and 7 are connected.
The bonding was performed so that the direction connecting b was orthogonal to each other in plan view. At this time, a spherical spacer (not shown) made of SiO ₂ and having a particle diameter of 15 μm was used so that the distance between the oxide films (transparent electrode films) 2 and 6 was 15 μm.

After that, the electrode terminals 3a and 3b provided on the oxide film (transparent electrode film) 2 and the DC power source V _{1 of} 15V were connected via the lead wires 10a and 10b. At this time, the switch S ₁ was interposed in the middle of the lead wire 10a, and the switch S ₂ was interposed in the middle of the lead wire 10b. In addition, electrode terminals 7a provided on the oxide film (transparent electrode film) 6,
7b and 15 V DC power supply V ₂ to lead wires 11a, 1
It was connected via 1b. At this time, the switch S ₃ was interposed in the middle of the lead wire 11a, and the switch S ₄ was interposed in the middle of the lead wire 11b. In this way, the electrode terminals 3a and 3b, the DC power source V ₁ , and the electrode terminals 7a and 7
The touch panel 15 was obtained by electrically connecting b and the DC power supply V ₂ .

(3) Evaluation of Touch Panel Performance Lead wire 10 of touch panel 15 produced in (2) above.
After grounding in the middle of b, a voltmeter 12 (see FIG. 2) for measuring the potential difference between the lead wire 10b and the lead wire 11a is installed, and then the switches S ₁ , S ₂ and S ₃ are closed and the switch and the S ₄ in the open. In this state, as indicated by arrow A in FIG. 2, along the line connecting the center of the electrode terminal 3a in the longitudinal direction and the center of the electrode terminal 3b in the longitudinal direction,
The outer surface of the transparent electrode substrate 1 is pressed from the side of the electrode terminal 3b toward the side of the electrode terminal 3a at a distance of 1.5 mm by a total of 100 points with an input pen 13 having a radius of curvature of 1 mm (see FIG. 2). The detection error at this time was calculated by the following equation.

[0055]

(Equation 1)

In the above equation, | V _n -V _n0 | represents the deviation of the measured voltage from the theoretical voltage, and the smaller this value, the less the false recognition of the pressed position can be obtained. | V _{n + 1} −V _n | in the above equation indicates the difference between the measured voltages at two adjacent pressing points, and the larger the value, the easier it is to detect the difference between the pressing positions as a potential difference with high accuracy. .

With respect to the touch panels obtained in the respective examples, the detection error was determined by the above formula, and as shown in Table 3 or Table 4 below, the value was less than 0.1 in any of the touch panels. Met. From this, it was confirmed that each touch panel had high input accuracy.

Example 73 (1) Preparation of transparent electrode substrate A glass plate (# 705 manufactured by Corning Incorporated) as a transparent substrate.
9; size 16 cm × 16 cm, thickness 1.1 mm. A transparent electrode substrate was obtained in the same manner as in Example 65 except that The atomic composition ratio in the sintering target used at this time and the atomic composition ratio in the formed oxide film are shown in Table 2.
It is described together. Regarding the oxide film (transparent electrode film) constituting the above transparent electrode substrate, Examples 1 to 72
The same items as those obtained in (1) were obtained in the same manner as in these examples. In addition, the light transmittance of the above transparent electrode substrate was determined in the same manner as in Examples 1 to 72 (1). The results are also shown in Table 4 below.

As shown in Table 4 below, the above oxide film has a high surface resistance of 1240 Ω / □ and has a high reproducibility as can be seen from the value of the standard deviation of the surface resistance. Is what you can get. Further, as is clear from the value of R / R ₀ , it has excellent heat resistance. From these, it is understood that the above-mentioned transparent electrode substrate has excellent characteristics suitable as a transparent electrode substrate for a touch panel, particularly an analog type touch panel.

(2) Manufacture of touch panel and performance evaluation Two transparent electrode substrates were prepared in total, and using these, analog type touch panels were manufactured in the same manner as in Example 1 to Example 72 (2). , The performance of Examples 1 to 7
Evaluation was performed in the same manner as in 2 (3). As a result, Table 4 below
As shown in, the value of the above-mentioned touch panel detection error was 0.03, and the input accuracy was high.

Comparative Examples 1 to 4 (1) Preparation of Transparent Electrode Substrate When forming an oxide film, the atomic composition ratio (excluding oxygen) shown in Table 2 below is used as a sputtering target.
In the same manner as in Example 1 to Example 72 (1) except that the sintered target made of the oxide of No. 1 was used, as shown in Table 2 below, the atomic composition ratio (oxygen) outside the range of the present invention was defined. Was formed on the PET fill to obtain a transparent electrode substrate for each comparative example. For each of the oxide films (transparent electrode films) constituting each transparent electrode substrate, the same items as those obtained in Examples 1 to 72 (1) were obtained in the same manner as in these examples. In addition, the light transmittances of the respective transparent electrode substrates are shown in Examples 1 to 72.
It was determined in the same manner as (1). These results are shown in Table 4 below.
Shown in

As shown in Table 4 below, each oxide film formed in Comparative Examples 1 and 2 has a surface resistance of 350.
Only Ω / □ or 450Ω / □, which does not satisfy the characteristics required for the transparent electrode film for obtaining a touch panel with high input accuracy. On the other hand, the oxide films formed in Comparative Examples 3 to 4 had extremely high surface resistance of 58230 Ω / □ or 29880 Ω / □.

(2) Preparation of touch panel and performance evaluation Examples 1 to 72 In the same manner as (2), an analog type touch panel was prepared for each comparative example, and its performance was evaluated in Examples 1 to 72 (3). ). As a result, as shown in Table 4 below, the value of the detection error of each touch panel in Comparative Examples 1 and 2 was 0.78 or 0.85.
The input accuracy was worse than that of each touch panel obtained in Examples 1 to 72 (2). Further, in each of the touch panels of Comparative Examples 3 to 4, the surface resistance of the oxide film (transparent electrode film) was too high, and therefore the DC power supply V _{1 of} 15 V was used.
And V ₂ (see FIG. 2) could not be activated and was not practical.

[0064]

[Table 1]

[0065]

[Table 2]

[0066]

[Table 3]

[0067]

[Table 4]

[0068]

As described above, according to the present invention, it is possible to provide a touch panel with high input accuracy.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the film thickness and the specific resistance of an oxide film (transparent electrode film) having a specific composition that constitutes the touch panel of the present invention.

FIG. 2 is a perspective view showing an outline of an analog type touch panel manufactured in Examples 1 to 73.

[Explanation of symbols]

 1,5 Transparent electrode substrate 2,6 Oxide film (transparent electrode film) 3a, 3b Electrode terminal 7a, 7b Electrode terminal 13 Input pen 15 Analog type touch panel

Claims (8)

[Claims] 1. A transparent electrode substrate having two transparent electrode films formed in a predetermined pattern, wherein the two transparent electrode substrates are arranged at a predetermined interval with the transparent electrode films facing each other. A touch panel in which the transparent electrode films are electrically connected to each other when a load is applied to the transparent electrode substrate from the outside of one of the transparent electrode substrates, wherein the transparent electrodes formed on each of the two transparent electrode substrates At least one of the films is made of indium (I
n) or tin (Sn) and titanium (T
i), silicon (Si), nickel (Ni), iridium (Ir), rhodium (Rh), cerium (Ce), zirconium (Zr), thallium (Tl), hafnium (Hf), magnesium (Mg), aluminum ( A
l), tantalum (Ta), cobalt (Co), lead (P)
b), germanium (Ge), chromium (Cr) and zinc (Zn), and at least one metal element selected from the group consisting of oxygen and oxygen (O) as constituent elements, and the atomic ratio of the total amount of the metal elements. (All metal atoms) / [(In or Sn)
+ (Total metal atoms)] is 2.2 to 40 at% and the film thickness and specific resistance of the transparent electrode film are the points A, B, C and D shown in FIG. 1 of the accompanying drawings. A touch panel that is within the range of a quadrangle that is the apex. 2. The oxide film comprises indium (In), titanium (Ti), silicon (Si) and zirconium (Z).
r), at least one metal element selected from the group consisting of aluminum (Al) and zinc (Zn) and oxygen (O) as constituent elements, and the atomic ratio of the total amount of the metal elements (total metal atoms) / [(In) + (all metal atoms)] is 2.
The touch panel according to claim 1, which is 5 to 30 at%. 3. The touch panel according to claim 1, which is a resistance film type touch panel. 4. The touch panel according to claim 1, wherein the touch panel is an analog type touch panel. 5. A transparent electrode substrate having two transparent electrode films formed in a predetermined pattern is provided, and the two transparent electrode substrates are arranged at a predetermined interval with the transparent electrode films facing each other. A touch panel in which the transparent electrode films are electrically connected to each other when a load is applied to the transparent electrode substrate from the outside of one of the transparent electrode substrates, wherein the transparent electrodes formed on each of the two transparent electrode substrates At least one of the films is made of indium (I
n), titanium (Ti), zinc (Zn) and oxygen (O)
As a constituent element, the atomic ratio (Ti + Zn) / (In + Ti) of the total amount of titanium (Ti) and zinc (Zn).
+ Zn) is an oxide film having a content of 2.2 to 50 at%,
The touch panel, wherein the film thickness and the specific resistance of the transparent electrode film are within the range of a quadrangle having points A, B, C and D as vertices shown in FIG. 1 of the accompanying drawings. 6. The atomic ratio In / (In + Ti + Zn) of indium (In) in the oxide film is 50 to 90 at%,
The atomic ratio of titanium (Ti) Ti / (In + Ti + Zn) is 1 to 20 at%, the atomic ratio of zinc (Zn) is Zn / (In + T).
The touch panel according to claim 5, wherein i + Zn) is 10 to 30 at%. 7. The touch panel according to claim 5, which is a resistive film type touch panel. 8. The touch panel according to claim 5, which is an analog type touch panel.