TW201545176A - Laminate, conductive laminate, and electronic device - Google Patents

Abstract

Provided is a laminate with excellent indium tin oxide film crystallization from heat treatment, and lowered sheet resistance of the indium tin oxide film after crystallization. The laminate has a transparent substrate and an indium tin oxide layer. The indium tin oxide layer is laminated to the transparent substrate and is primarily made up of amorphous indium tin oxide. The indium tin oxide layer has a hydrogen concentration not exceeding 0.60 at%. Also, the indium tin oxide layer has a sheet resistance not exceeding 200 [Omega]/- after heat treatment with a heat treatment temperature of 150 DEG C and a heat treatment time of 30 minutes.

Description

Laminated body, conductive laminated body, and electronic equipment

The present invention relates to a laminate, a conductive laminate, and an electronic device.

Since the transparent conductive film has conductivity and optical transparency, it can be used as a transparent electrode, an electromagnetic wave shielding film, a planar heat radiation film, an anti-reflection film, etc., and has been attracting attention as an electrode for a touch panel in recent years. There are various methods such as a resistive film type, an electrostatic capacitance coupling type, and an optical type in the touch panel. The transparent conductive film is, for example, an electrostatic capacitance coupling method for a resistive film type in which a touch position is specified by contact of upper and lower electrodes, and a change in electrostatic capacitance is sensed. For the transparent conductive film used for the resistive film type, the transparent conductive films are mechanically in contact with each other in principle, and therefore high durability is required. Further, since the transparent conductive film used for the capacitive coupling method or a part of the resistive film type is formed into a specific pattern, a large number of transparent electrodes are formed by etching, and therefore etching property is required to be good. Further, since the transparent conductive film is disposed on the front surface of the display portion, high light transmittance is required.

As the transparent conductive film, an indium tin oxide film is known as a representative one. In the case of an indium tin oxide film, the etching property is good when it is amorphous, and the durability is good when it is crystalline. Therefore, as a method for improving the etching property, the durability, and the like, it is known that an amorphous indium tin oxide film is formed, followed by etching, and further heat treatment to form a crystalline indium tin oxide film. method. In the case of such a method, the indium tin oxide film is required to be changed from amorphous to crystalline (hereinafter also referred to as good crystallization) by heat treatment.

Further, the indium tin oxide film is also required to have a small specific resistance. In the case of smaller specific resistance At this time, the thickness can be reduced, whereby the transmittance can be improved. In the case of an indium tin oxide film, the higher the ratio of tin in terms of oxide, the higher the carrier density and the smaller the specific resistance. On the other hand, the higher the ratio of tin in terms of oxide, the more difficult it is to crystallize by heat treatment. Therefore, the industry requires a small specific resistance and good crystallization by heat treatment.

Heretofore, a method of heat-treating an amorphous indium tin oxide film to form a crystalline indium tin oxide film has been known (for example, refer to Patent Documents 1 and 2). Further, in order to improve the moisture resistance reliability of the indium tin oxide film, it is known that the temperature of the substrate on which the indium tin oxide film is formed and the water pressure in the film formation environment are adjusted to a specific range by sputtering. Film formation is performed (for example, refer to Patent Document 3).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2012/161095

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2013-084376

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-096158

An object of the present invention is to provide a laminate in which the indium tin oxide film formed by the heat treatment is crystallized well and the sheet resistance of the indium tin oxide film after crystallization is sufficiently reduced. Further, an object of the present invention is to provide a conductive laminated body in which an indium tin oxide film is well crystallized and a sheet resistance of an indium tin oxide film is sufficiently small. Further, it is an object of the invention to provide an electronic device having such a conductive laminate.

The laminate of the present invention has a transparent substrate and an indium tin oxide layer. The indium tin oxide layer is laminated on the transparent substrate and mainly contains amorphous indium tin oxide. Further, the indium tin oxide layer has a hydrogen concentration of 0.60 at% or less. Further, the sheet resistance of the indium tin oxide layer after the heat treatment at a heat treatment temperature of 150 ° C and a heat treatment time of 30 minutes was 200 Ω / □ or less.

The conductive laminate of the present invention has a transparent substrate and an indium tin oxide layer. The indium tin oxide layer is laminated on the transparent substrate and mainly contains crystalline indium tin oxide. Further, the indium tin oxide layer has a hydrogen concentration of 0.60 at% or less. Further, the indium tin oxide layer has a sheet resistance of 200 Ω/□ or less.

The electronic device of the present invention has the electroconductive laminate of the present invention.

The laminate of the present invention has an indium tin oxide layer having a hydrogen concentration of 0.60 at% or less. Thereby, the crystallization of the indium tin oxide layer by the heat treatment becomes good, and the sheet resistance after the heat treatment of the indium tin oxide layer is also sufficiently reduced.

10‧‧‧Layer

11‧‧‧Transparent substrate

12‧‧‧ basal layer

13‧‧‧Amorphous indium tin oxide layer

13a‧‧‧ Part of the indium tin oxide layer 13

13b‧‧‧There is no part of the indium tin oxide layer 13

20‧‧‧Electrical laminate

21‧‧‧ crystalline indium tin oxide layer

21a‧‧‧ Part of the indium tin oxide layer 21

21b‧‧‧There is no part of the indium tin oxide layer 21

Fig. 1 is a cross-sectional view showing an example of a laminate of the present invention.

Fig. 2 is a cross-sectional view showing an example of the conductive laminate of the present invention.

Hereinafter, the present invention will be described in detail.

Fig. 1 is a cross-sectional view showing an embodiment of a laminate.

The laminated body 10 has, for example, a transparent substrate 11, a base layer 12, and an amorphous indium tin oxide layer 13 in this order. Here, the indium tin oxide layer 13 is a crystalline indium tin oxide layer by heat treatment.

Further, the indium tin oxide layer is amorphous or crystalline, and is determined as follows. First, the evaluation object was immersed in a HCl solution (concentration: 1.5 mol/L) for 5 minutes. The rate of change in resistance (sheet resistance after immersion/sheet resistance before immersion) was determined from the sheet resistance values before and after immersion. A crystal having a resistance change rate of 200% or less is used as a crystal, and an electric resistance change rate exceeding 200% is used as an amorphous material. The well-crystallized indium tin oxide layer has a small rate of change in resistance.

The ease of crystallization by the heat treatment of the indium tin oxide layer 13 and the magnitude of the specific resistance (wherein the film thickness of the indium tin oxide layer 13 is fixed and assumed to be a specific value) depends on the indium. The content of tin in the tin oxide layer 13 in terms of oxide is usually in a trade-off relationship. However, in the laminated body 10, the hydrogen concentration of the indium tin oxide layer 13 is 0.60 at% or less, and even when the content of tin in the indium tin oxide layer 13 is large in terms of oxide, it is performed by heat treatment. The crystallization is also good and the durability is also good. And the sheet resistance can be reduced. Specifically, the sheet resistance of the indium tin oxide layer 13 after the heat treatment is 200 Ω/□ or less. As a method of heat treatment, the laminate may be heated to a desired temperature, and for example, an infrared heater or a hot air circulation type oven may be used. As the heat treatment conditions, for example, the heat treatment temperature is 150 ° C, and the heat treatment time is 30 minutes.

(transparent substrate)

The transparent substrate 11 is preferably, for example, an unstretched or stretched plastic film of a polyolefin such as polyethylene or polypropylene; polyethylene terephthalate, polybutylene terephthalate or polynaphthalene. Polyester such as ethylene diformate; polyamine which is nylon 6, nylon 66; polyimine, polyarylate, polycarbonate, polyacrylate, polyether oxime, polyfluorene; copolymers of these. Further, as the transparent substrate 11, other plastic films having a high transparency and a glass substrate can be used. Further, the transparent substrate may have a single layer structure or a laminate structure having two or more layers having different compositions. As the transparent substrate 11, a polyethylene terephthalate film is particularly preferable.

A hard coat layer, a primer layer, an undercoat layer, or the like may be provided on one or both sides of the transparent substrate 11. Here, the hard coat layer is such that the transparent substrate 11 is less likely to be damaged. The undercoat layer is used to improve the adhesion of organic materials to inorganic materials. The primer coating is a refractive index adjusting layer or the like which reduces the visibility of the etching pattern formed on the indium tin oxide layer 13. Further, the transparent substrate 11 can be subjected to surface treatment such as easy subsequent treatment, plasma treatment, or corona treatment. The thickness of the transparent substrate 11 is preferably 10 μm or more and 200 μm or less, and more preferably 25 μm or more and 180 μm or less from the viewpoints of flexibility, durability, and the like.

(base layer)

The underlayer 12 is not necessarily required, and in order to promote crystallization of the indium tin oxide layer 13 by heat treatment, it is preferable to provide the underlayer 12. As a constituent material of the base layer 12, Inorganic compounds such as metals, oxides, sulfides, and fluorides thereof are listed. Among these, ruthenium oxide and aluminum oxide are preferable, and ruthenium oxide is further preferable, and SiOx (x is 1.5 to 2) is particularly preferable. Cerium oxide is preferred from the viewpoint of shielding the oligomer or the eluted material such as moisture from the substrate. The base layer 12 may have a single layer structure or a laminate structure having two or more layers having different compositions.

The thickness of the underlayer 12 is preferably 1 nm or more, more preferably 3 nm or more, still more preferably 5 nm or more. When the thickness of the underlayer 12 is 1 nm or more, the effect of promoting crystallization becomes remarkable. When the thickness of the underlayer 12 is about 10 nm, it is sufficient for crystallization, and when it is 10 nm or less, the productivity or transparency of the underlayer 12 is good.

(indium tin oxide layer)

The indium tin oxide layer 13 is amorphous and is crystallized by heat treatment. Since it is amorphous, the etching property is good. Moreover, it is made into a crystal by heat processing, and durability is also favorable. Patterning can be performed by etching, and a portion 13a in which the indium tin oxide layer 13 exists and a portion 13b in which the indium tin oxide layer 13 is not present are provided in the indium tin oxide layer 13. Further, the indium tin oxide layer 13 may have a single layer structure or a laminate structure having two or more layers having different compositions. The indium tin oxide layer 13 is preferably in contact with the underlayer 12 in terms of crystallization by heat treatment.

The indium tin oxide layer 13 mainly contains indium tin oxide, which is an oxide of indium and tin. Examples of the oxide constituting the indium tin oxide include indium oxide, tin oxide, a composite oxide of indium oxide and tin oxide, and the like.

The hydrogen concentration of the indium tin oxide layer 13 is 0.60 at% (atomic %) or less. Here, the hydrogen concentration is a ratio of hydrogen elements contained in the indium tin oxide layer 13. When the hydrogen concentration is 0.60 at% or less, even if the content of tin is large in terms of oxide, the crystallization by heat treatment is also good. Therefore, the content of tin in terms of oxide can be increased, the sheet resistance can be reduced, and the durability is also good. The hydrogen concentration is preferably 0.55 at% or less, and more preferably 0.50 at% or less, from the viewpoint that the crystallization by heat treatment is further improved. The lower the hydrogen concentration The better, it can be 0at%.

The hydrogen concentration can be quantitatively determined by secondary ion mass spectrometry (SIMS) or high-resolution back-scatter scattering analysis (ERDA). Further, it is considered that the hydrogen in the indium tin oxide layer 13 is absorbed from the moisture, the hydrocarbon compound, or the hydrogen in the film forming chamber which is discharged from the transparent substrate in the film formation.

Further, the sheet resistance after heat treatment of the indium tin oxide layer 13 is 200 Ω/□ or less. When the sheet resistance is 200 Ω/□ or less, it is preferably used in an electronic machine. The sheet resistance is preferably 170 Ω/□ or less, more preferably 140 Ω/□ or less, still more preferably 100 Ω/□ or less. In order to reduce the sheet resistance, it is effective to thicken the thickness of the indium tin oxide layer 13, but from the viewpoint of suppressing the thickness of the indium tin oxide layer 13 from becoming too thick, the sheet resistance is preferably 10 Ω/□ or more. More preferably, it is 20 Ω/□ or more, further preferably 30 Ω/□ or more, and particularly preferably 40 Ω/□ or more. The heat treatment conditions may be such that the indium tin oxide layer 13 is heated to a good degree of crystallization. For example, the heat treatment temperature is 150 ° C, and the heat treatment time is 30 minutes.

It is preferable that the indium tin oxide contains 5% by mass or more and 15% by mass or less of tin in terms of oxide. When the amount of tin is 5 mass% or more in terms of oxide, the density of the carrier after crystallization increases, and the specific resistance becomes low. On the other hand, in the case where tin is contained in an amount of 15% by mass or less in terms of oxide, crystallization becomes easy. From the viewpoint of easiness of crystallization and specific resistance, it is more preferable that the indium tin oxide contains 6% by mass or more of tin, and more preferably 7% by mass or more. Moreover, it is more preferable that the indium tin oxide contains 13% by mass or less of tin in terms of oxide, and more preferably 10% by mass or less. Further, regarding the easiness of crystallization, in the present case, crystallization is so easy that the heat treatment conditions are low temperature and crystallization is performed in a short time.

In the case where the indium tin oxide layer 13 has a laminated structure, the tin oxide conversion concentration is replaced by a weighted average of the tin oxide conversion concentration of all the layers constituting the indium tin oxide layer.

The indium tin oxide layer 13 is preferably composed of only indium tin oxide, but may be needed and not The components other than indium tin oxide are contained within the limits of the gist of the present invention. Examples of the component other than the indium tin oxide include oxides of aluminum, zirconium, gallium, germanium, tungsten, zinc, titanium, magnesium, lanthanum, cerium, and the like. The content of the component other than the indium tin oxide layer in the indium tin oxide layer 13 is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, more preferably in the entire indium tin oxide layer 13. It is 1% by mass or less.

The thickness of the indium tin oxide layer 13 is preferably 15 nm or more. When the thickness is 15 nm or more, crystallization by heat treatment becomes easy, and the sheet resistance after crystallization is also lowered. The thickness of the indium tin oxide layer 13 is more preferably 18 nm or more. On the other hand, the thickness of the indium tin oxide layer 13 is preferably 40 nm or less. When the thickness is 40 nm or less, the film formation time is reduced and the transmittance is also high. The thickness of the indium tin oxide layer 13 is more preferably 30 nm or less, still more preferably 27 nm or less.

The indium tin oxide layer 13 is crystallized by heat treatment. The heat treatment can usually be carried out in the atmosphere. The heat treatment temperature is preferably 100 ° C or higher and the heat treatment time is preferably 30 minutes or longer in terms of the crystallization of the indium tin oxide layer 13 being good. On the other hand, in terms of suppressing the damage of the transparent substrate 11, and the productivity is also good, the heat treatment temperature is preferably 170 ° C or lower, and the heat treatment time is preferably 180 minutes or shorter.

Next, the conductive laminated body 20 will be described.

FIG. 2 is a cross-sectional view showing an example of the conductive laminated body 20. The conductive laminated body 20 can be obtained by heat-treating the laminated body 10. The conductive laminate 20 has, for example, a transparent substrate 11 , a base layer 12 , and a crystalline indium tin oxide layer 21 . The transparent substrate 11 and the underlayer 12 are the same as the transparent substrate 11 and the underlayer 12 in the laminate 10.

Since the indium tin oxide layer 21 is crystalline, the durability is improved. The portion 21a in which the indium tin oxide layer 21 exists and the portion 21b in which the indium tin oxide layer 21 is not present may be provided in the indium tin oxide layer 21 by pattern formation by etching. Examples of the etching pattern include a plurality of transparent electrodes and the like. From the viewpoint of crystallization, the indium tin oxide layer 21 is preferably in contact with the underlayer 12.

The indium tin oxide layer 21 mainly contains indium tin oxide, which is an oxide of indium and tin. Examples of the oxide constituting the indium tin oxide include indium oxide, tin oxide, a composite oxide of indium oxide and tin oxide, and the like. Further, the indium tin oxide layer 21 may have a single layer structure or a laminate structure having two or more layers having different compositions.

The hydrogen concentration of the indium tin oxide layer 21 is 0.60 at% or less. When the hydrogen concentration is 0.60 at% or less, even if the content of tin is large in terms of oxide, the crystallization by heat treatment is also good. Therefore, the content of tin in terms of oxide can be increased, the sheet resistance can be reduced, and the durability is also good. The hydrogen concentration is preferably 0.55 at% or less, and more preferably 0.50 or less, from the viewpoint that the crystallization by heat treatment is further improved. The lower the hydrogen concentration, the better, and it may be 0 at%.

The hydrogen concentration can be quantitatively determined by secondary ion mass spectrometry (SIMS) or high-resolution back-scatter scattering analysis (ERDA). Further, it is considered that the hydrogen in the indium tin oxide layer 13 is absorbed from the moisture, the hydrocarbon compound, or the hydrogen in the film forming chamber which is discharged from the transparent substrate in the film formation.

The sheet resistance of the indium tin oxide layer 21 is 200 Ω/□ or less. When the sheet resistance is 200 Ω/□ or less, it is preferable for an electronic device. The sheet resistance is preferably 170 Ω/□ or less, more preferably 140 Ω/□ or less, still more preferably 100 Ω/□ or less. In order to reduce the sheet resistance, it is effective to thicken the thickness of the indium tin oxide layer 13, and from the viewpoint of suppressing the thickness of the indium tin oxide layer 13 from becoming excessive, the sheet resistance is preferably 10 Ω/□ or more, more preferably It is 20 Ω/□ or more, more preferably 30 Ω/□ or more, and particularly preferably 40 Ω/□ or more.

It is preferable that the indium tin oxide contains 5% by mass or more and 15% by mass or less of tin in terms of oxide. In the case where tin is contained in an amount of 5 mass% or more in terms of oxide, the carrier density increases and the specific resistance becomes low. On the other hand, in the case where tin is contained in an amount of 15% by mass or less in terms of oxide, the crystallinity is improved. From the viewpoint of easiness of crystallization and specific resistance, it is more preferable that the indium tin oxide contains 6% by mass or more of tin, and more preferably 7% by mass or more. Moreover, it is more preferable that the indium tin oxide contains 13% by mass or less of tin in terms of oxide, and more preferably 10% by mass or less.

The indium tin oxide layer 21 is preferably made of only indium tin oxide, but may contain components other than indium tin oxide as needed, without departing from the gist of the present invention. Examples of the component other than the indium tin oxide include oxides of aluminum, zirconium, gallium, germanium, tungsten, zinc, titanium, magnesium, lanthanum, cerium, and the like. The content of the component other than the indium tin oxide layer in the indium tin oxide layer 21 is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, more preferably in the entire indium tin oxide layer 21. It is 1% by mass or less.

The thickness of the indium tin oxide layer 21 is preferably 15 nm or more. When the thickness is 15 nm or more, crystallization by heat treatment becomes easy, and sheet resistance is also lowered. The thickness of the indium tin oxide layer 21 is more preferably 18 nm or more. On the other hand, the thickness of the indium tin oxide layer 21 is preferably 40 nm or less. When the thickness is 40 nm or less, the film formation time is reduced and the transmittance is increased. And the reflectance difference becomes low. The thickness of the indium tin oxide layer 21 is more preferably 30 nm or less, still more preferably 27 nm or less.

The following reflectance difference ΔR in the conductive laminated body 20 is preferably 1% or less. When the reflectance difference ΔR is 1% or less, the visibility of the etching pattern formed on the indium tin oxide layer 21 is sufficiently lowered. The reflectance difference ΔR is preferably 0.8% or less, more preferably 0.7% or less, and most preferably 0.6% or less.

The reflectance difference ΔR is such that the transparent substrate 11 side serves as a light incident surface, and the average reflectance R ₁ [%] at a position of the indium tin oxide layer 21 at a wavelength of 480 nm or more and 650 nm or less and the absence of indium tin are present. The absolute value (ΔR = |R _{1 -} R ₂ |) of the difference between the average reflectance R ₂ [%] of the wavelength of 480 nm or more and 650 nm or less at the position of the oxide layer 21 . In the case where the conductive laminate 20 has the underlayer 12, the average reflectance R ₂ is measured in a state in which the underlayer 12 is provided. The adjustment of the reflectance difference ΔR can be performed by adjusting the thickness, refractive index, and the like of each layer.

The conductive laminate 20 can be preferably used in an electronic device, and is particularly preferably used in an electronic device having a display portion and a touch panel disposed on a front surface of the display portion. The conductive laminate 20 is particularly useful as a substrate having a transparent electrode in a touch panel. As a touch surface The plate includes a resistive film type in which a touch position is specified by contact of upper and lower electrodes, and a capacitive coupling method in which a change in electrostatic capacitance is sensed.

Next, a method of manufacturing the laminated body 10 and the conductive laminated body 20 will be described.

The layered body 10 can be formed by forming the underlying layer 12 on the transparent substrate 11 as needed, and then forming the indium tin oxide layer 13. The film formation method is not necessarily limited, and a sputtering method, an ion plating method, a vacuum evaporation method, or a sputtering method is preferable.

The indium tin oxide layer 13 is formed, for example, by sputtering using a sputtering target containing indium tin oxide. The sputtering target is preferably indium tin oxide containing 5% by mass or more and 15% by mass or less of tin in terms of oxide. The indium tin oxide in the sputtering target preferably contains a sintered body obtained by mixing tin oxide (SnO ₂ ) and indium oxide (In ₂ O ₃ ) and sintering the same.

The film formation of the indium tin oxide layer 13 is preferably performed by, for example, a mixed gas obtained by mixing 0.5 to 10% by volume, preferably 0.8 to 6% by volume of oxygen, into an argon gas. By performing sputtering while introducing such a mixed gas, it is possible to form an amorphous film, to perform crystallization by heat treatment, and to reduce the sheet resistance after crystallization.

At this time, the hydrogen concentration of the indium tin oxide layer 13 can be made 0.60 at% or less by sufficiently reducing the hydrogen concentration in the film formation environment. As a method of sufficiently reducing the concentration of hydrogen in the film formation environment, for example, the film forming chamber is baked before film formation, and moisture and hydrocarbon compounds adsorbed on the wall surface of the film forming chamber are sufficiently discharged; A cold trap for adsorbing moisture and a hydrocarbon compound is disposed; the transparent substrate 11 is heated in advance to sufficiently remove moisture, hydrocarbon compounds, and the like contained in the substrate.

The conductive laminated body 20 is obtained by heat-treating the laminated body 10. The heat treatment can usually be carried out in the atmosphere. The heat treatment temperature is preferably 100 ° C or higher and the heat treatment time is preferably 30 minutes or longer in terms of the crystallization of the indium tin oxide layer 13 being good. On the other hand, in terms of suppressing the damage of the transparent substrate 11, and the productivity is also good, the heat treatment temperature is preferably 170 ° C or lower, and the heat treatment time is preferably 180 minutes or shorter. Furthermore, it is considered that the hydrogen concentration does not change before and after the heat treatment. Therefore, amorphous indium tin oxide When the hydrogen concentration of the layer 13 is 0.60 at% or less, the hydrogen concentration of the crystalline indium tin oxide layer 21 is preferably 0.60 at% or less.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples. Examples 1, 2, 5 to 7, 10 to 14 are examples of the present invention, and Examples 3, 4, 8, 9, and 15 are comparative examples of the present invention. Furthermore, the invention is not limited by the embodiments. Moreover, the thickness of each layer is obtained based on optical characteristics, or film formation speed, and the conveyance speed of a base material, and it is not the actual measurement.

(example 1)

A hard coat layer containing an acrylic resin having a thickness of 8 μm was formed on both sides of a polyethylene terephthalate film having a thickness of 100 μm as a transparent substrate. A ruthenium oxide layer (SiO ₂ layer) having a thickness of about 70 angstroms is formed on the transparent substrate as a base layer. The SiO ₂ layer is formed by using a boron-doped polycrystalline germanium target and introducing a mixed gas of 28% by volume of oxygen in an argon gas, and performing AC (alternating current) magnetron sputtering under a pressure of 0.2 Pa. . Furthermore, the thickness of the SiO ₂ layer is adjusted in accordance with the power density and the sputtering time.

On the transparent substrate on which the underlayer is formed, an indium tin oxide layer (ITO layer) containing amorphous indium tin oxide, having a thickness of 298 angstroms, and a hydrogen concentration which does not reach the detection limit of the measuring device is formed. Into a test piece.

The film formation of the ITO layer is carried out by DC (direct current) magnetron sputtering. The target system is a target obtained by mixing and sintering a 12.5% by mass of tin oxide (SnO ₂ ) and 81.5% by mass of indium oxide (In ₂ O ₃ ) (hereinafter referred to as a 12.5 ITO target). Further, the environment was a mixed gas obtained by mixing 1.4% by volume of oxygen in argon gas, and the pressure was set to 0.25 Pa. The thickness of the ITO layer is adjusted according to the power density and the sputtering time. It is estimated that the content of tin in the ITO layer in terms of oxide is approximately 12.5% by mass.

(Example 2~15)

A test piece was produced by forming an ITO layer in the same manner as in Example 1 except that the composition of the target and the hydrogen concentration and thickness of the ITO layer were changed as shown in Table 1.

In the table, "12.5 ITO" indicates that tin oxide is contained in an amount of 12.5% by mass in terms of oxide, "10 ITO" indicates that 10% by mass of tin is contained in terms of oxide, and "7.5 ITO" indicates conversion in terms of oxide. It contains 7.5 mass% tin.

Next, the test pieces of the respective examples were heat-treated at 120 ° C, 130 ° C, 140 ° C, 150 ° C, and 30 minutes in the atmosphere. The following evaluation was performed on the heat-treated test piece. The results are shown in Table 1.

[hydrogen concentration]

The hydrogen concentration of the heat-treated ITO layer was measured by high-resolution ERDA. Further, in order to eliminate the influence of the contaminant, the range from the position of 5 nm to the position of 10 nm was measured from the surface of the ITO layer in the thickness direction. The average of these measured values is shown in the table as the hydrogen concentration. Further, since the hydrogen concentration does not change due to the heat treatment, it is considered that the hydrogen concentration of the ITO layer before the heat treatment is also the same. Further, "-" in the table indicates that the hydrogen concentration does not reach the detection limit of the measuring machine. The detection limit of the measuring machine was 0.3 at%.

[Sheet resistance]

The test piece was cut into a size of 100 mm × 100 mm, and the sheet resistance was measured by a probe method using Lorester (manufactured by Mitsubishi Chemical Corporation, trade name). Further, the sheet resistance was measured for the test piece before the heat treatment and the test piece after the heat treatment. Further, "ND" in the table indicates that there is no measurement data.

[Crystallinity]

The heat-treated test piece was immersed in a HCl solution (concentration: 1.5 mol/L) for 5 minutes. The rate of change in electrical resistance ((sheet resistance after immersion/sheet resistance before immersion) × 100 [%]) was determined from the sheet resistance value of the ITO layer before and after immersion. A crystal having a resistance change rate of 200% or less is used as a crystal, and an electric resistance change rate exceeding 200% is used as an amorphous material. In the table, for those whose resistance change rate exceeds 200% (which is amorphous), the "x" mark is also indicated in the result of the sheet resistance. In the sheet resistance, the test piece was cut into a size of 100 mm × 100 mm, and measured by a four-probe method using Lorester (trade name, manufactured by Mitsubishi Chemical Corporation). Further, the resistance change rate of the ITO layer was measured in the same manner as in the test piece before the heat treatment, and it was confirmed that all of them were amorphous.

[reflectance difference ΔR]

For the test piece after heat treatment at 150 ° C for 30 minutes, the transparent substrate side was used as the light incident surface, and the average reflectance R ₁ [%] at a position of the ITO layer at a wavelength of 480 nm or more and 650 nm or less was observed. The average reflectance R ₂ [%] at a position where the ITO layer is not present at a wavelength of 480 nm or more and 650 nm or less is measured. Further, the portion where the ITO layer is not present for determining the average reflectance R ₂ is used to include a transparent substrate and a base layer. The reflectance difference ΔR (ΔR = |R _{1 -} R ₂ |) was obtained from the measured values. The measurement was performed using a spectrophotometer UV3150 (manufactured by Shimadzu Corporation, trade name).

According to Table 1, it is clear that when the hydrogen concentration of the indium tin oxide layer is 0.60 at% or less, crystallization is performed by heat treatment even if it contains 5% by mass or more of tin in terms of oxide and has a thickness of 40 nm or less. Also good, the sheet resistance is also 200 Ω / □ or less.

10‧‧‧Layer

11‧‧‧Transparent substrate

12‧‧‧ basal layer

13‧‧‧Amorphous indium tin oxide layer

13a‧‧‧ Part of the indium tin oxide layer 13

13b‧‧‧There is no part of the indium tin oxide layer 13

Claims (10)

A laminated body comprising: a transparent substrate; and an indium tin oxide layer laminated on the transparent substrate and mainly containing amorphous indium tin oxide, and the hydrogen concentration of the indium tin oxide layer is 0.60 at The sheet resistance after heat treatment at a heat treatment temperature of 150 ° C and a heat treatment time of 30 minutes or less is 200 Ω / □ or less. The laminate according to claim 1, wherein the indium tin oxide layer has a thickness of 40 nm or less. The laminate according to claim 1 or 2, wherein the indium tin oxide layer contains 5% by mass or more and 15% by mass or less of tin in terms of an oxide. The laminate according to any one of claims 1 to 3, which has a ruthenium oxide layer between the transparent substrate and the indium tin oxide layer. A conductive laminated body comprising: a transparent substrate; and an indium tin oxide layer laminated on the transparent substrate and mainly containing crystalline indium tin oxide, and the hydrogen concentration of the indium tin oxide layer is 0.60 Below at%, and the sheet resistance is 200 Ω/□ or less. The conductive laminate according to claim 5, wherein the indium tin oxide layer has a thickness of 40 nm or less. The conductive laminate according to claim 5 or 6, wherein the indium tin oxide layer contains 5% by mass or more and 15% by mass or less of tin in terms of an oxide. The conductive laminate according to any one of claims 5 to 7, which has a ruthenium oxide layer between the transparent substrate and the indium tin oxide layer. The conductive laminate according to any one of claims 5 to 8, wherein the position of the indium tin oxide layer is at a wavelength of 480 nm or more and 650 nm or less when the transparent substrate side is used as a light incident surface. The average reflectance R ₁ [%] and the absolute value of the difference between the average reflectance R ₂ [%] of the wavelength of 480 nm or more and 650 nm or less at the position where the indium tin oxide layer is not present, that is, the reflectance difference ΔR is 1% or less. An electronic machine having the electroconductive laminate according to any one of claims 5 to 9.