WO2015064664A1

WO2015064664A1 - Electrically conductive substrate and method for manufacturing electrically conductive substrate

Info

Publication number: WO2015064664A1
Application number: PCT/JP2014/078817
Authority: WO
Inventors: 渡辺　宏幸; 山岸　浩一; 永田　純一; 高塚　裕二; 貞之横林
Original assignee: 住友金属鉱山株式会社
Priority date: 2013-10-31
Filing date: 2014-10-29
Publication date: 2015-05-07
Also published as: CN105706182B; KR20160081925A; TW201540137A; JP6330818B2; TWI646870B; CN105706182A; KR102170097B1; JPWO2015064664A1

Abstract

[Solution] This invention provides an electrically conductive substrate provided with the following: a transparent base material, a copper layer or layers formed on at least one surface of said transparent base material, and a blackening layer or layers that is/are formed on at least one surface of the transparent base material and contain(s) oxygen, nitrogen, nickel, and tungsten.

Description

Conductive substrate, method for manufacturing conductive substrate

The present invention relates to a conductive substrate and a method for manufacturing a conductive substrate.

As disclosed in Patent Document 1, a transparent conductive film for a touch panel in which an ITO (indium-tin oxide) film is formed as a transparent conductive film on a polymer film has been conventionally used.

By the way, in recent years, a display with a touch panel has been increased in screen size, and in response to this, a conductive substrate such as a transparent conductive film for a touch panel is required to have a large area. However, since ITO has a high electric resistance value, there is a problem that it cannot cope with an increase in the area of the conductive substrate.

For this reason, for example, as disclosed in Patent Documents 2 and 3, the use of a metal foil such as copper instead of the ITO film has been studied. However, for example, when copper is used for the wiring layer, since copper has a metallic luster, there is a problem that the visibility of the display decreases due to reflection.

Therefore, a conductive substrate in which a blackening layer having a color capable of suppressing light reflection on the surface of the wiring layer is studied together with a wiring layer made of a metal foil such as copper. However, in order to obtain a conductive substrate having a wiring pattern, it is necessary to form a desired pattern by etching the wiring layer and the blackened layer after forming the wiring layer and the blackened layer. There is a problem that the reactivity to the liquid is different between the wiring layer and the blackened layer. That is, if the wiring layer and the blackened layer are simultaneously etched, one of the layers cannot be etched into the target shape. In addition, when the wiring layer etching and the blackening layer etching are performed in separate steps, there is a problem that the number of steps increases.

Japanese Unexamined Patent Publication No. 2003-151358 Japanese Unexamined Patent Publication No. 2011-018194 Japanese Unexamined Patent Publication No. 2013-0669261

In view of the above-described problems of the prior art, an object of the present invention is to provide a conductive substrate provided with a copper layer and a blackened layer that can be simultaneously etched.

In order to solve the above problems, the present invention
A transparent substrate;
A copper layer formed on at least one surface of the transparent substrate;
A conductive substrate provided with a blackening layer formed on at least one surface side of the transparent base material and containing oxygen, nitrogen, nickel, and tungsten is provided.

According to the present invention, it is possible to provide a conductive substrate including a copper layer and a blackened layer that can be etched simultaneously.

Sectional drawing of the electroconductive board | substrate which concerns on embodiment of this invention. Sectional drawing of the electroconductive board | substrate which concerns on embodiment of this invention. The top view of the electroconductive board | substrate provided with the mesh-shaped wiring which concerns on embodiment of this invention. Sectional drawing in the AA 'line of FIG. The wavelength dependence of the reflectance of the electroconductive board | substrate which concerns on Experimental example 1. FIG.

Hereinafter, an embodiment of a conductive substrate and a method for manufacturing the conductive substrate of the present invention will be described.
(Conductive substrate)
The conductive substrate of this embodiment includes a transparent base material,
A copper layer formed on at least one side of the transparent substrate;
It can be set as the structure provided with the blackening layer (henceforth a "blackening layer" only) formed in the at least one surface side of a transparent base material containing oxygen, nitrogen, nickel, and tungsten.

The conductive substrate in this embodiment is a substrate having a copper layer or a blackened layer on the surface of a transparent substrate before patterning a copper layer or the like, and a wiring shape by patterning the copper layer or blackened layer. And a wiring board.

Here, first, each member included in the conductive substrate of the present embodiment will be described below.

The transparent substrate is not particularly limited, and an insulating film that transmits visible light, a glass substrate, or the like can be preferably used.

As the insulator film that transmits visible light, for example, a polyamide film, a polyethylene terephthalate film, a polyethylene naphthalate film, a cycloolefin film, a polyimide film, or a resin film can be preferably used.
In particular, PET (polyethylene terephthalate), COP (cycloolefin polymer), PEN (polyethylene naphthalate), polyimide, polycarbonate, or the like can be preferably used as a material for a resin substrate that transmits visible light.

The thickness of the transparent base material is not particularly limited, and can be arbitrarily selected according to the strength, capacitance, light transmittance, and the like required for a conductive substrate. As thickness of the transparent base material of a transparent base material, it can be 10 micrometers or more and 200 micrometers or less, for example. In particular, when used for touch panel applications, the thickness of the transparent substrate is preferably 20 μm or more and 120 μm or less, and more preferably 20 μm or more and 100 μm or less. In the case of use for touch panel applications, for example, particularly in applications where it is required to reduce the thickness of the entire display, the thickness of the transparent substrate is preferably 20 μm or more and 50 μm or less.

Next, the copper layer will be described.

The copper layer is not particularly limited, but it is preferable not to dispose an adhesive between the copper layer and the transparent substrate or between the blackened layer in order not to reduce the light transmittance. That is, the copper layer is preferably formed directly on the upper surface of another member.

In order to directly form a copper layer on the upper surface of another member, the copper layer preferably has a copper thin film layer. Moreover, the copper layer may have a copper thin film layer and a copper plating layer.

For example, a copper thin film layer can be formed on a transparent substrate or a blackened layer by a dry plating method to form the copper thin film layer. Thereby, a copper layer can be formed directly on a transparent base material or a blackening layer, without passing an adhesive agent.

When the copper layer is thick, the copper thin film layer is used as a power feeding layer, and a copper plating layer is formed by a wet plating method to form a copper layer having a copper thin film layer and a copper plating layer. You can also. Since the copper layer has the copper thin film layer and the copper plating layer, the copper layer can be directly formed on the transparent substrate or the blackening layer without using an adhesive.

The thickness of the copper layer is not particularly limited, and when the copper layer is used as a wiring, it can be arbitrarily selected according to the magnitude of the current supplied to the wiring, the wiring width, and the like. In particular, the thickness of the copper layer is preferably 50 nm or more, more preferably 150 nm or more so that sufficient current can be supplied. The upper limit value of the thickness of the copper layer is not particularly limited, but if the copper layer becomes thick, side etching occurs because etching takes time when performing etching to form a wiring, and the resist peels off during the etching. Etc. are likely to occur. For this reason, the thickness of the copper layer is preferably 3 μm or less, more preferably 700 nm or less, and even more preferably 200 nm or less. For example, in applications where the length of the wiring is long, such as a large screen touch panel, it is preferable to sufficiently reduce the resistance value of the wiring, so that the copper layer is made thick according to the size of the screen to be applied and the wiring length. be able to.

When the copper layer has a copper thin film layer and a copper plating layer as described above, the total of the thickness of the copper thin film layer and the thickness of the copper plating layer is preferably in the above range.

Next, the blackening layer containing oxygen, nitrogen, nickel, and tungsten will be described.

Since the copper layer has a metallic luster, the copper reflects light as described above only by forming the wiring obtained by etching the copper layer on the transparent substrate. For example, when used as a conductive substrate for a touch panel, There was a problem that visibility was lowered. Therefore, a method of providing a blackened layer has been studied, but the blackened layer may not have sufficient reactivity with the etching solution, and the copper layer and the blackened layer are simultaneously etched into a desired shape. It was difficult. Therefore, the inventors of the present invention have studied, and the layer containing oxygen, nitrogen, nickel, and tungsten can be used for the blackening layer because it has a color that can suppress the reflection of light. The present inventors have found that an etching process can be performed simultaneously with the copper layer in order to exhibit sufficient reactivity.

The method for forming the blackened layer is not particularly limited, and the film can be formed by any method. However, since the blackening layer can be formed relatively easily, it is preferable to form the film by sputtering.

The blackening layer can be formed by sputtering, for example, using a nickel-tungsten alloy target and supplying oxygen and nitrogen into the chamber. Note that a nickel target and a tungsten target can be used to form a film by a sputtering method while supplying oxygen and nitrogen into the chamber. The supply ratio of oxygen and nitrogen supplied into the chamber is not particularly limited, but oxygen is supplied into the chamber at a rate of 5% to 20% by volume and nitrogen is supplied at a rate of 30% to 55% by volume. However, it is preferable to form a film by a sputtering method.

As described above, by setting the ratio of oxygen supply to the chamber to 5% by volume or more, the color of the blackened layer can be changed to a color that can sufficiently suppress the reflection of light, and functions as a blackened layer. Is preferable because it can sufficiently exhibit the above. The supply ratio of oxygen into the chamber is more preferably 10% by volume or more. Further, by making the supply amount of oxygen 20% by volume or less, the reactivity of the blackened layer with respect to the etching solution can be particularly increased. When etching with the copper layer, the copper layer and the blackened layer are added. A desired pattern can be easily formed, which is preferable. The supply ratio of oxygen into the chamber is more preferably 15% by volume or less.

Nitrogen can be easily etched by adding it to the atmosphere when forming the blackened layer, but if the amount added is too large, the reflection of light cannot be sufficiently suppressed, and the performance as a blackened layer May decrease. For this reason, the supply ratio of nitrogen during sputtering is preferably 30% by volume or more and 55% by volume or less, and more preferably 35% by volume or more and 40% by volume or less. Note that it is preferable to set the nitrogen supply ratio to 55% by volume or less because the sputtering rate of the blackened layer can be secured. Supplying nitrogen into the chamber so that the supply ratio of nitrogen is 40% by volume or less is more preferable because the sputtering rate of the blackened layer is further improved.

In addition, when performing sputtering, the gas supplied into the chamber is preferably an inert gas for the remainder other than oxygen and nitrogen. For the remainder other than oxygen and nitrogen, for example, argon or helium can be supplied.

Also, as described above, for example, a nickel-tungsten alloy target can be used as a target used when performing sputtering. The composition of the target is not particularly limited, but the nickel-tungsten alloy target preferably contains tungsten in a proportion of 5 wt% to 30 wt%, and contains tungsten in a proportion of 18 wt% to 30 wt%. More preferably. In these cases, the balance can be made of nickel.

It is preferable to set the tungsten content in the nickel-tungsten alloy target to 5 wt% or more because the magnetism of the target can be kept low. In particular, when the tungsten content is 18% by weight or more, it is more preferable because the magnetism of the target can be further reduced.

In addition, when the tungsten content in the target of the nickel-tungsten alloy increases, the workability of the target may decrease. That is, it may be difficult to target. However, it is preferable that the tungsten content is 30% by weight or less because the workability of the nickel-tungsten alloy is sufficiently high and can be easily targeted.

The formed blackened layer only needs to contain oxygen, nitrogen, nickel, and tungsten, and oxygen, nitrogen, nickel, and tungsten may be contained in any form. For example, nickel and tungsten form an alloy, and a nickel-tungsten alloy containing oxygen and / or nitrogen may be contained in the blackening layer. Nickel or tungsten is an oxide or nitride such as nickel oxide (NiO), nickel nitride (Ni ₃ N), tungsten oxide (WO ₃ , WO ₂ , W ₂ O ₃ ), tungsten nitride (N ₂ W), or the like. And the compound may be contained in the blackened layer.

The blackening layer may be a layer composed of only one kind of substance containing oxygen, nitrogen, nickel, and tungsten simultaneously, such as a nickel-tungsten alloy containing oxygen and nitrogen. Further, for example, it contains one or more substances selected from the above-mentioned nickel-tungsten alloy containing oxygen and / or nitrogen, nickel oxide, nickel nitride, tungsten oxide, tungsten nitride. It may be a layer.

The thickness of the blackening layer is not particularly limited, but is preferably 15 nm or more, for example, and more preferably 20 nm or more. As described above, the blackening layer has a function of suppressing the reflection of light. However, when the thickness of the blackening layer is thin, the reflection of light may not be sufficiently suppressed. On the other hand, it is preferable to make the thickness of the blackened layer in the above range because reflection of light can be further suppressed.

The upper limit of the thickness of the blackening layer is not particularly limited, but even if it is thicker than necessary, the time required for film formation and the time required for etching when forming the wiring are increased, resulting in an increase in cost. Will be invited. For this reason, the thickness of the blackened layer is preferably 70 nm or less, and more preferably 40 nm or less.

Further, when the specific resistance of the blackened layer is sufficiently small, a contact portion with an electric member such as a wiring can be formed on the blackened layer, and the copper layer is exposed even when the blackened layer is located on the outermost surface. This is preferable because it is unnecessary.

In order to form a contact portion with an electric member such as a wiring in the blackened layer, the specific resistance of the blackened layer is preferably 2.00 × 10 ⁻² Ω · cm or less. More preferably, it is 00 × 10 ⁻³ Ω · cm or less. According to the study of the inventors of the present invention, the specific resistance of the blackened layer has a correlation with the oxygen concentration in the atmosphere when the blackened layer is formed. The lower the oxygen concentration in the atmosphere when forming the blackened layer, the lower the specific resistance of the blackened layer, which is preferable. In particular, when the specific resistance of the blackened layer is sufficiently low, the oxygen concentration when forming the blackened layer is preferably 15% by volume or less, more preferably 13% by volume or less, and more preferably 10% by volume. The following is more preferable.

Next, a configuration example of the conductive substrate of this embodiment will be described.

As described above, the conductive substrate of this embodiment includes a transparent substrate, a copper layer, and a blackening layer containing oxygen, nitrogen, nickel, and tungsten. Under the present circumstances, the order of lamination | stacking at the time of arrange | positioning a copper layer and a blackening layer on a transparent base material is not specifically limited. Further, a plurality of copper layers and blackening layers can be formed. In order to suppress light reflection, it is preferable that a blackening layer is disposed on the surface of the copper layer where light reflection is particularly desired to be suppressed. More preferably, the copper layer has a structure sandwiched between blackening layers.

Furthermore, when a blackened layer having a low specific resistance is included as described above, the blackened layer having a low specific resistance is preferably disposed on the outermost surface of the conductive substrate. This is because the blackened layer having a small specific resistance can be connected to an electric member such as a wiring, and is preferably disposed on the outermost surface of the conductive substrate so as to be easily connected.

A specific configuration example will be described below with reference to FIGS. 1 and 2 show examples of cross-sectional views of the conductive substrate of this embodiment on a plane parallel to the lamination direction of the transparent base material, the copper layer, and the blackening layer.

For example, as in the conductive substrate 10A shown in FIG. 1A, the copper layer 12 and the blackening layer 13 can be laminated one layer at a time on the one surface 11a side of the transparent base material 11. . Moreover, like the electroconductive board | substrate 10B shown in FIG.1 (b),

copper layer

12A, 12B on the one surface 11a side of the transparent base material 11, and the other surface (other surface) 11b side, respectively. And the blackening

layers

13A and 13B can be stacked one by one in that order. In addition, the order which laminates | stacks the copper layer 12 (12A, 12B) and the blackening layer 13 (13A, 13B) is not limited to the example of Fig.1 (a), (b), From the transparent base material 11 side. The blackening layer 13 (13A, 13B) and the copper layer 12 (12A, 12B) can be laminated in this order. Thus, when the blackening layer 13 is arrange | positioned between the transparent base material 11 and the copper layer 12, since the adhesiveness of the transparent base material 11 and the copper layer 12 can be improved with the blackening layer 13, it is preferable. For example, also in the case of having the structure shown in FIG. 2A described later, the first blackening layer 131 can improve the adhesion between the transparent base material 11 and the copper layer 12 for the same reason.

Further, for example, a configuration in which a plurality of blackening layers are provided on one surface side of the transparent substrate 11 can be employed. For example, like the conductive substrate 20A shown in FIG. 2A, the first blackened layer 131, the copper layer 12, and the second blackened layer 132 are formed on the one surface 11a side of the transparent substrate 11. Can be stacked in that order.

In this case as well, a configuration in which a copper layer, a first blackened layer, and a second blackened layer are laminated on both surfaces of the transparent substrate 11 can be adopted. Specifically, as in the conductive substrate 20B shown in FIG. 2B, the first surface 11a side of the transparent base material 11 and the other surface (the other surface) 11b side are respectively first. Blackening layers 131A and 131B,

copper layers

12A and 12B, and second blackening layers 132A and 132B can be stacked in that order.

In FIGS. 1B and 2B, when a copper layer and a blackening layer are laminated on both surfaces of the transparent base material, the transparent base material 11 serves as a symmetrical surface and the top and bottom of the transparent base material 11 are aligned. Although the example which arrange | positioned so that the laminated | stacked layer might become symmetrical was shown, it is not limited to the form which concerns. For example, in FIG. 2B, the configuration on the one surface 11a side of the transparent substrate 11 is formed by laminating the copper layer 12 and the blackening layer 13 in that order, similarly to the configuration of FIG. The layers laminated on the top and bottom of the transparent substrate 11 may be asymmetrical.

Up to this point, the conductive substrate of the present embodiment has been described. However, in the conductive substrate of the present embodiment, the copper layer and the blackened layer are provided on the transparent base material. Reflection can be suppressed.

The degree of light reflection of the conductive substrate of the present embodiment is not particularly limited, but for example, the conductive substrate of the present embodiment preferably has a reflectance of light having a wavelength of 550 nm of 40% or less. 30% or less is more preferable, and 20% or less is particularly preferable. This is preferable when the reflectance of light having a wavelength of 550 nm is 40% or less, for example, even when used as a conductive substrate for a touch panel, since the display visibility hardly deteriorates.

The reflectance can be measured by irradiating the blackened layer with light. That is, measurement can be performed from the blackened layer side of the copper layer and the blackened layer included in the conductive substrate.

Specifically, for example, when the copper layer 12 and the blackened layer 13 are laminated in this order on one surface 11a of the transparent substrate 11 as shown in FIG. 1A, the blackened layer 13 can be irradiated with light. It can be measured from the surface side indicated by middle A.

In addition, when the arrangement of the copper layer 12 and the blackened layer 13 is changed from that in the case of FIG. 1A and the blackened layer 13 and the copper layer 12 are laminated in this order on one surface 11a of the transparent base material 11, The reflectance can be measured from the surface 11b side of the transparent substrate 11, which is the side on which the layer 13 is located on the outermost surface.

As will be described later, the conductive substrate can form wiring by etching the copper layer and the blackened layer, but the reflectance is arranged on the outermost surface when the transparent substrate is removed from the conductive substrate. The reflectance of the blackened layer on the surface on the light incident side is shown. For this reason, if it is before an etching process or after performing an etching process, it is preferable that the measured value in the part in which the copper layer and the blackening layer remain satisfy | fills the said range.

The conductive substrate of this embodiment can be preferably used as a conductive substrate for a touch panel, for example, as described above. In this case, the conductive substrate can be configured to have mesh wiring.

The conductive substrate provided with the mesh-like wiring can be obtained by etching the copper layer and the blackening layer of the conductive substrate of the present embodiment described so far.

For example, a mesh-like wiring can be formed by two-layer wiring. A specific configuration example is shown in FIG. FIG. 3 shows a view of the conductive substrate 30 provided with mesh-like wiring as viewed from the upper surface side in the stacking direction of the copper layer and the blackened layer. The conductive substrate 30 shown in FIG. 3 has a transparent base material 11, a plurality of wirings 31A parallel to the X-axis direction in the drawing, and wirings 31B parallel to the Y-axis direction. FIG. 3 shows an example in which the mesh-like wiring (wiring pattern) is formed by combining the

linear wirings

31A and 31B. However, the present invention is not limited to such a configuration, and the wiring pattern is configured. The wiring can have any shape. For example, the shapes of the

wirings

31A and 31B constituting the mesh-like wiring pattern so as not to cause moiré (interference fringes) between the images on the display are changed to various shapes such as jagged lines (zigzag straight lines). You can also.

The

wirings

31A and 31B are formed by etching a copper layer, and a blackening layer (not shown) is formed on the upper and / or lower surfaces of the

wirings

31A and 31B. The blackened layer is etched in the same shape as the

wirings

31A and 31B.

The arrangement of the transparent substrate 11 and the

wirings

31A and 31B is not particularly limited. An example of the arrangement of the transparent substrate 11 and the wiring is shown in FIGS. 4A and 4B correspond to cross-sectional views taken along the line AA ′ of FIG.

First, as shown in FIG. 4A, wirings 31A and 31B may be arranged on the upper and lower surfaces of the transparent substrate 11, respectively. In this case, blackening

layers

32A and 32B etched in the same shape as the wiring are disposed on the upper surfaces of the

wirings

31A and 31B.

Further, as shown in FIG. 4B, a pair of

transparent base materials

11A and 11B are used, and

wirings

31A and 31B are arranged on the upper and lower surfaces with one transparent base material 11A interposed therebetween, and one wiring 31B may be disposed between the transparent substrate 11A and the transparent substrate 11B. Also in this case, blackened

layers

wirings

31A and 31B. As described above, the arrangement of the blackened layer and the copper layer is not limited. For this reason, in any of FIGS. 4A and 4B, the arrangement of the blackening layers 32A and 32B and the

wirings

31A and 31B can be reversed upside down. For example, a plurality of blackening layers can be provided.

However, the blackened layer is preferably disposed on the surface of the copper layer surface where light reflection is particularly desired to be suppressed. Therefore, in the conductive substrate shown in FIG. 4B, for example, when it is necessary to suppress the reflection of light from the lower surface side in the figure, the position of the blackened layer 32B, the position of the wiring 31B, Is preferably reversed. Further, in addition to the blackening layer 32B, a blackening layer may be further provided between the wiring 31B and the transparent substrate 11B.

The conductive substrate having the mesh-like wiring shown in FIG. 3 and FIG. 4A includes, for example,

copper layers

12A and 12B on both surfaces of the transparent substrate 11 as shown in FIG. 1B and FIG. , And blackened

layers

13A and 13B (131A, 132A, 131B, and 132B).

The case where it is formed using the conductive substrate of FIG. 1B will be described as an example. First, the copper layer 12A and the blackened layer 13A on the one surface 11a side of the transparent base material 11 are shown in FIG. Etching is performed so that a plurality of linear patterns parallel to the X-axis direction are arranged at predetermined intervals. The X-axis direction in FIG. 1 (b) means a direction parallel to the width direction of each layer in FIG. 1 (b).

A plurality of linear patterns parallel to the Y-axis direction in FIG. 1B are arranged at predetermined intervals on the copper layer 12B and the blackened layer 13B on the other surface 11b side of the transparent substrate 11. Etching is performed so that In addition, the Y-axis direction in FIG.1 (b) means the direction perpendicular | vertical to a paper surface.

The conductive substrate having the mesh-like wiring shown in FIGS. 3 and 4A can be formed by the above operation. Note that the etching of both surfaces of the transparent substrate 11 can be performed simultaneously. That is, the etching of the

copper layers

12A and 12B and the blackening layers 13A and 13B may be performed simultaneously.

3 can be formed by using two conductive substrates shown in FIG. 1A or FIG. 2A. The conductive substrate having a mesh-like wiring shown in FIG. The case where the conductive substrate of FIG. 1A is used will be described as an example. For the two conductive substrates shown in FIG. 1A, the copper layer 12 and the blackened layer 13 are parallel to the X-axis direction, respectively. Etching is performed so that a plurality of linear patterns are arranged at predetermined intervals. Then, the conductive substrate having mesh-like wiring is obtained by bonding the two conductive substrates so that the linear patterns formed on the respective conductive substrates intersect with each other by the etching process. be able to. The surface to be bonded when the two conductive substrates are bonded is not particularly limited. The surface A in FIG. 1A in which the copper layer 12 or the like is laminated as shown in FIG. The surface 11b in FIG. 1A on which the layer 12 and the like are not stacked may be bonded.

In addition, it is preferable that the blackening layer is disposed on the surface of the copper layer surface where light reflection is particularly desired to be suppressed. Therefore, in the conductive substrate shown in FIG. 4B, when it is necessary to suppress the reflection of light from the lower surface side in the figure, the position of the blackened layer 32B and the position of the wiring 31B are reversed. It is preferable to arrange in. Further, in addition to the blackening layer 32B, a blackening layer may be further provided between the wiring 31B and the transparent substrate 11B.

Further, for example, the surfaces 11b in FIG. 1A where the copper layer 12 or the like of the transparent substrate 11 is not laminated may be bonded so that the cross section has the structure shown in FIG.

Note that the width of the wiring and the distance between the wirings in the conductive substrate having the mesh-like wiring shown in FIGS. 3 and 4 are not particularly limited, and are selected according to, for example, the amount of current flowing through the wiring. can do.

Thus, a conductive substrate having a mesh-like wiring composed of two layers of wiring can be preferably used as a conductive substrate for a projected capacitive touch panel, for example.
(Method for producing conductive substrate)
Next, a configuration example of the method for manufacturing a conductive substrate according to this embodiment will be described.

The manufacturing method of the conductive substrate of this embodiment is as follows:
A transparent substrate preparation step of preparing a transparent substrate;
A copper layer forming step of forming a copper layer on at least one surface side of the transparent substrate;
It is preferable to have a blackening layer forming step of forming a blackening layer containing oxygen, nitrogen, nickel, and tungsten on at least one surface side of the transparent substrate.

Hereinafter, the manufacturing method of the conductive substrate according to the present embodiment will be described. However, the configuration other than the following will be the same as that of the above-described conductive substrate, and the description thereof will be omitted.

As described above, in the conductive substrate of the present embodiment, the order of stacking when the copper layer and the blackened layer are disposed on the transparent base material is not particularly limited. Further, a plurality of copper layers and blackening layers can be formed. For this reason, the order of the copper layer forming step and the blackened layer forming step and the number of times of execution are not particularly limited, and are performed at an arbitrary number of times according to the structure of the conductive substrate to be formed. be able to.

The step of preparing the transparent base material is a step of preparing a transparent base material made of, for example, an insulating film that transmits visible light, a glass substrate, or the like, and the specific operation is not particularly limited. For example, in order to use for each process in a latter process, it can cut | disconnect etc. to arbitrary sizes as needed.

Next, the copper layer forming process will be described.

As described above, the copper layer preferably has a copper thin film layer. Moreover, it can also have a copper thin film layer and a copper plating layer. For this reason, a copper layer formation process can have a process of forming a copper thin film layer, for example with a dry plating method. Moreover, the copper layer forming step may include a step of forming a copper thin film layer by a dry plating method and a step of forming a copper plating layer by a wet plating method using the copper thin film layer as a power feeding layer. .

The dry plating method used for forming the copper thin film layer is not particularly limited, and for example, a vacuum deposition method, a sputtering method, an ion plating method, or the like can be used. In particular, as the dry plating method used for forming the copper thin film layer, it is more preferable to use the sputtering method because the film thickness can be easily controlled.

The process of forming a copper thin film layer will be described taking the case of using a winding type sputtering apparatus as an example. First, a copper target is mounted on a sputtering cathode, and a base material, specifically, a transparent base material on which a transparent base material or a blackened layer is formed is set in a vacuum chamber. After evacuating the inside of the vacuum chamber, Ar gas is introduced to maintain the inside of the apparatus at about 0.13 Pa to 1.3 Pa. In this state, the substrate is transported from the unwinding roll at a speed of, for example, about 1 to 20 m / min, and power is supplied from the DC power source for sputtering connected to the cathode, and sputtering discharge is performed. The copper thin film layer can be continuously formed.

The conditions in the step of forming the copper plating layer by the wet plating method, that is, the conditions of the electroplating treatment are not particularly limited, and various conditions according to ordinary methods may be adopted. For example, a copper plating layer can be formed by supplying a base material on which a copper thin film layer is formed in a plating tank containing a copper plating solution and controlling the current density and the conveyance speed of the base material.

Next, the blackening layer forming process will be described.

The blackening layer forming step is not particularly limited, but as described above, the blackening layer can be formed by sputtering.

In this case, a nickel-tungsten alloy target can be used as the target. Further, as described above, a nickel target and a tungsten target can also be used. When a nickel-tungsten alloy target is used as the target, the nickel-tungsten alloy target preferably contains tungsten in a proportion of 5 wt% to 30 wt%. More preferably, the nickel-tungsten alloy target contains tungsten in a proportion of 18 wt% to 30 wt%. In this case, the remainder can be made of nickel.

Further, it is preferable to perform sputtering while supplying oxygen in the chamber at a rate of 5% by volume to 20% by volume and nitrogen at a rate of 30% by volume to 55% by volume.

In particular, the supply ratio of oxygen into the chamber is more preferably 10% by volume to 15% by volume. Further, the supply ratio of nitrogen into the chamber is more preferably 35% by volume to 40% by volume.

And as for the electroconductive board | substrate obtained by the manufacturing method of the electroconductive board | substrate demonstrated here, it is preferable that the thickness of a copper layer is 50 nm or more like the above-mentioned electroconductive board | substrate, and shall be 150 nm or more. More preferred. The upper limit value of the thickness of the copper layer is not particularly limited, but is preferably 3 μm or less, more preferably 700 nm or less, and further preferably 200 nm or less. For example, in applications where the length of the wiring is long, such as a large screen touch panel, it is preferable to sufficiently reduce the resistance value of the wiring, so that the copper layer is made thick according to the size of the screen to be applied and the wiring length. be able to.

Also in the conductive substrate obtained by the conductive substrate manufacturing method described here, the thickness of the blackening layer is not particularly limited, but is preferably 15 nm or more, for example, 20 nm or more. It is more preferable. The upper limit value of the thickness of the blackening layer is not particularly limited, but is preferably 70 nm or less, and more preferably 40 nm or less.

If the formed blackened layer has a sufficiently small specific resistance, it is possible to form a contact portion with an electric member such as wiring on the blackened layer, and the copper layer is exposed even when the blackened layer is located on the outermost surface. This is preferable because there is no need to do this.

In order to form a contact portion with an electric member such as a wiring in the blackened layer, the specific resistance of the blackened layer is preferably 2.00 × 10 ⁻² Ω · cm or less. It is preferably 00 × 10 ⁻³ Ω · cm or less. According to the study of the inventors of the present invention, the specific resistance of the blackened layer has a correlation with the oxygen concentration in the atmosphere when the blackened layer is formed. The lower the oxygen concentration in the atmosphere when forming the blackened layer, the lower the specific resistance of the blackened layer, which is preferable. In particular, when the specific resistance of the blackened layer is sufficiently low, the oxygen concentration when forming the blackened layer is preferably 15% by volume or less, more preferably 13% by volume or less, and more preferably 10% by volume. More preferably, it is as follows.

Furthermore, also in the conductive substrate obtained by the conductive substrate manufacturing method described herein, the reflectance of light having a wavelength of 550 nm is preferably 40% or less, more preferably 30% or less, and 20%. It is particularly preferred that This is preferable when the reflectance of light having a wavelength of 550 nm is 40% or less, for example, even when used as a conductive substrate for a touch panel, since the display visibility hardly deteriorates.

The conductive substrate obtained by the method for manufacturing a conductive substrate described herein can be a conductive substrate provided with mesh-like wiring. In this case, in addition to the above-described steps, an etching step of forming a wiring by etching the copper layer and the blackening layer can be further included.

In this etching step, for example, first, a resist having an opening corresponding to a portion to be removed by etching is formed on the outermost surface of the conductive substrate. In the case of the conductive substrate shown in FIG. 1A, a resist can be formed on the exposed surface A of the blackening layer 13 disposed on the conductive substrate. Note that a method for forming a resist having an opening corresponding to a portion to be removed by etching is not particularly limited. For example, the resist can be formed by a photolithography method.

Next, the copper layer 12 and the blackened layer 13 can be etched by supplying an etching solution from the upper surface of the resist.

In addition, when a copper layer and a blackening layer are disposed on both surfaces of the transparent substrate 11 as shown in FIG. 1B, a resist having openings of predetermined shapes on the outermost surfaces A and B of the conductive substrate. The copper layer and the blackened layer formed on both surfaces of the transparent substrate 11 may be etched simultaneously.

In addition, the copper layer and the blackened layer formed on both sides of the transparent substrate 11 can be subjected to an etching process on one side. That is, for example, after the copper layer 12A and the blackened layer 13A are etched, the copper layer 12B and the blackened layer 13B can be etched.

Since the blackening layer exhibits the same reactivity to the etching solution as the copper layer, the etching solution used in the etching step is not particularly limited, and an etching solution generally used for etching the copper layer is preferably used. be able to. As the etching solution, for example, a mixed aqueous solution of ferric chloride and hydrochloric acid can be used more preferably. The contents of ferric chloride and hydrochloric acid in the etching solution are not particularly limited. For example, ferric chloride is preferably contained in a proportion of 5 wt% to 50 wt%, and preferably 10 wt%. More preferably, it is contained in a proportion of 30% by weight or less. Further, for example, the etching solution preferably contains hydrochloric acid in a proportion of 1 wt% or more and 50 wt% or less, and more preferably contains 1 wt% or more and 20 wt% or less. The remainder can be water.

Although the etching solution can be used at room temperature, it is preferably heated to increase the reactivity. For example, it is preferably heated to 40 ° C. or more and 50 ° C. or less.

Since the specific form of the mesh-like wiring obtained by the above-described etching process is as described above, the description thereof is omitted here.

In addition, as described above, two conductive substrates having a copper layer and a blackened layer are bonded to one side of the transparent base material 11 shown in FIGS. 1A and 2A and meshed. In the case where the conductive substrate is provided with a conductive wiring, a step of bonding the conductive substrate can be further provided. At this time, a method for bonding the two conductive substrates is not particularly limited, and the bonding can be performed using, for example, an adhesive.

The conductive substrate and the method for manufacturing the conductive substrate of the present embodiment have been described above. According to such a conductive substrate, since the copper layer and the blackened layer show substantially the same reactivity with the etching solution, a desired wiring can be easily formed. Moreover, the blackening layer can suppress reflection of light, and for example, when a conductive substrate for a touch panel is used, a reduction in visibility can be suppressed.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited to these Examples.
[Experiment 1]
The conductive substrate prepared based on the sample preparation conditions described later was evaluated by the following evaluation method.
(Evaluation methods)
(1) Reflectance The reflectance was measured before conducting the dissolution test of the copper layer and the blackened layer on the conductive substrate prepared in each of the following experimental examples.

The measurement was performed by installing a reflectance measurement unit in an ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation, model: UV-2550).

With respect to the outermost surface A in FIG. 1A on the side where the copper layer and blackening layer of the conductive substrate prepared in each experimental example are formed, the incident angle is 5 ° and the light receiving angle is 5 °, and the wavelength is 400 nm or more and 700 nm or less. The reflectance when irradiating light in the range was measured.
(2) Dissolution test The conductive substrate produced in each of the following experimental examples was immersed in an etching solution, and a dissolution test of the copper layer and the blackened layer was performed.

As the etching solution, an aqueous solution containing 10% by weight of ferric chloride, 10% by weight of hydrochloric acid and the balance being water was used, and the temperature of the etching solution was room temperature (25 ° C.).

After immersing in the etching solution for 1 minute, the conductive substrate was taken out of the etching solution, and when the copper layer and the blackened layer were completely dissolved and only the transparent substrate was formed, it was evaluated as “good”.

If the copper layer or blackened layer still remains when removed from the etchant, immerse in the same etchant for an additional 1 minute, and when removed from the etchant, the copper layer and blackened layer will be completely It was evaluated as Δ when it was dissolved only in the transparent substrate. When the copper layer or the blackened layer remained even after the second immersion in the etching solution, it was evaluated as x.
(Sample preparation conditions)
The manufacturing conditions of the conductive substrate in each experimental example are shown below. Experimental examples 1-1, 1-2, and 1-4 to 1-7 are examples, and experimental example 1-3 is a comparative example.
[Experimental Example 1-1]
A conductive substrate having the structure shown in FIG.

First, a transparent substrate 11 made of polyethylene terephthalate resin (PET) having a length of 5 cm, a width of 5 cm, and a thickness of 0.02 mm was prepared.

Next, a copper layer 12 was formed on the entire surface of one side of the transparent substrate 11. The copper layer 12 formed a copper thin film layer by a sputtering method, and then formed a copper plating layer by a wet plating method using the copper thin film layer as a power feeding layer. Specifically, a copper thin film layer having a thickness of 100 nm was first formed on one surface of the transparent substrate 11 by a direct current sputtering method using a Cu target (manufactured by Sumitomo Metal Mining Co., Ltd.). Thereafter, a copper plating layer was laminated by 0.5 μm by electroplating to form a copper layer 12.

Next, a blackened layer 13 was formed on the entire surface of the copper layer 12 by a direct current sputtering method.

The blackening layer 13 was formed using a sputtering apparatus (model: CFS-4ES-2 manufactured by Shibaura Mechatronics Co., Ltd.).

Specific conditions for sputtering will be described below.

A nickel-tungsten alloy target containing 19% by weight of tungsten and the balance being nickel was used as the target. Nitrogen, oxygen, and argon were supplied into the chamber while supplying a total of 15 SCCM. Each gas was supplied to the chamber so that 45% by volume of nitrogen, 5% by volume of oxygen, and the balance were argon, and sputtering was performed. The ultimate vacuum in the chamber before sputtering was 1 × 10 ⁻³ Pa.

In the chamber, the copper layer 12 of the transparent base material 11 on which the copper layer 12 was formed was placed so as to face the target, and the distance between the copper layer 12 and the target was 85 mm, thereby forming the copper layer 12. Sputtering was performed while rotating the transparent substrate 11 at 15 rpm. When the blackening layer was formed by sputtering, a current of 0.6 A and a voltage of 330 V (power value of about 200 W) were applied to the target by a DC power source.

The blackened layer 13 having a thickness of 30 nm was formed by the sputtering method.

The conductive substrate obtained by the above steps was subjected to reflectance measurement and dissolution test. The reflectance measurement results are shown in FIG. 5 and Table 1, and the dissolution test results are shown in Table 1.
[Experimental Example 1-2]
The blackening layer 13 was formed in the same manner as in Experimental Example 1-1 except that each gas was supplied in the chamber so that nitrogen was 40% by volume, oxygen was 10% by volume, and the balance was argon. Note that the gas is supplied into the chamber so that the total gas becomes 15 SCCM.

The results are shown in FIG.
[Experimental Example 1-3]
The blackening layer 13 was formed in the same manner as in Experimental Example 1-1 except that each gas was supplied so that oxygen was 25% by volume and the balance was argon. Note that the gas is supplied into the chamber so that the total gas becomes 15 SCCM.

The results are shown in FIG.
[Experimental Example 1-4]
The blackening layer 13 was formed in the same manner as in Experimental Example 1-1, except that each gas was supplied so that nitrogen was 40% by volume, oxygen was 3% by volume, and the balance was argon. Note that the gas is supplied into the chamber so that the total gas becomes 15 SCCM.

The results are shown in FIG.
[Experiment 1-5]
The blackening layer 13 was formed in the same manner as in Experimental Example 1-1, except that each gas was supplied so that nitrogen was 40% by volume, oxygen was 25% by volume, and the balance was argon. Note that the gas is supplied into the chamber so that the total gas becomes 15 SCCM.

The results are shown in FIG.
[Experimental Example 1-6]
The blackening layer 13 was formed in the same manner as in Experimental Example 1-1 except that each gas was supplied so that 30% by volume of nitrogen, 10% by volume of oxygen, and the balance became argon in the chamber. Note that the gas is supplied into the chamber so that the total gas becomes 15 SCCM.

The results are shown in FIG.
[Experiment 1-7]
The blackening layer 13 was formed in the same manner as in Experimental Example 1-1 except that each gas was supplied so that the volume of nitrogen was 55% by volume, oxygen was 10% by volume, and the balance was argon. Note that the gas is supplied into the chamber so that the total gas becomes 15 SCCM.

The results are shown in FIG.

According to the results shown in FIG. 5 and Table 1, the experimental examples 1-1, 1-2, and 1-4 to 1-7, which are examples, are evaluated as “good” or “small” in the dissolution test. The layer and the blackened layer could be dissolved simultaneously.

In contrast, for Experimental Example 1-3, which is a comparative example, the reflectance for light at 550 nm is lower than that of Experimental Examples 1-1, 1-2, 1-4, 1-6, 1-7. In the dissolution test, the blackened layer remained without being dissolved. This is probably because nitrogen was not supplied into the chamber when the blackened layer was formed, so that the blackened layer did not contain nitrogen and the reactivity with the etching solution was low.

In addition, Experimental Example 1-5 has the same oxygen supply amount as Experimental Example 1-3, which is a comparative example, but it was confirmed that Δ was obtained in the dissolution test evaluation. This is presumably because the reactivity of the blackened layer to the etching solution was increased by simultaneously supplying nitrogen when forming the blackened layer.

Although it was confirmed that the reflectance with respect to light having a wavelength of 550 nm was low in any of the experimental examples, the experimental examples 1-1, 1-2, and 1-4 to 1-7 except the experimental example 1-3. Thus, it was confirmed that the reflectance was particularly low at 40% or less in the conductive substrates of Experimental Examples 1-1, 1-2, and 1-5 to 1-7. This is presumably because oxygen was sufficiently supplied when the blackened layer was formed, so that the blackened layer became a color capable of suppressing light reflection.
[Experiment 2]
The conductive substrate prepared based on the sample preparation conditions described later was evaluated by the following evaluation method.
(Evaluation methods)
(1) Reflectance and dissolution test Since the reflectance and dissolution test were measured by the method described in Experimental Example 1, description thereof is omitted.
(2) Specific resistance Transparent substrate under the same conditions except for the conditions for producing the conductive substrate shown in the following experimental examples, the point that the thickness of the blackened layer was 500 nm, and the point that the copper layer was not formed A sample in which only the blackened layer was formed (hereinafter, a similar sample is also referred to as “sample for measuring specific resistance”) was produced, and the specific resistance of the blackened layer was evaluated. In addition, also about the blackening layer composition evaluation and EDS analysis which are mentioned later, it evaluates similarly using the sample for measurement, such as a specific resistance.

The specific resistance was measured using a four-point probe method. In the four-probe method, four needle-shaped electrodes are arranged on the same line on the surface of the sample to be measured, a constant current is passed between the two outer probes, and the potential difference between the two inner probes is measured. This is a method of measuring resistance. Measurement was performed using a four-point probe measuring instrument (Mitsubishi Chemical Co., Ltd. model: Loresta IP).

Then, according to the following equation (1), the specific resistance ρ was calculated by multiplying the resistance value (V / I) measured using the four-probe method with a correction coefficient RCF (Resistency Correction Factor) and film thickness (t). .
ρ = V / I × RCF × t Formula (1)
(3) Composition evaluation of the blackened layer In the composition evaluation of the blackened layer, the production conditions of the conductive substrate shown in each experimental example, the point that the thickness of the blackened layer was 500 nm, and the copper layer were not formed. Except for the points, a specific resistance measurement sample in which only a blackened layer was formed on a transparent substrate under the same conditions was subjected to X-ray diffraction (XRD) measurement, and the obtained X-ray diffraction pattern was used.

As described above, the blackening layer is formed on a substrate made of polyethylene terephthalate resin (PET), which is a transparent substrate. And since the blackened layer of the sample used for the measurement has a thin film thickness of 500 nm, when X-ray diffraction measurement is performed, the diffraction pattern not only from the blackened layer but also from the transparent substrate becomes large and is included in the blackened layer It may be difficult to identify the phase of the material.

Here, when performing normal X-ray diffraction measurement, a plurality of rings (Debye rings) are observed concentrically with respect to the incident angle of X-rays. In a randomly oriented polycrystal, a plurality of rings having different strengths are observed, and the strength is substantially constant in the same ring. On the other hand, when it is not a polycrystal with random orientation, that is, when it has orientation, a plurality of concentric rings are observed, but the intensity is not constant within the same ring, and shading can be achieved. Moreover, it becomes a spot in the single crystal, which matches the electron beam diffraction pattern.

When the transparent substrate has a single crystal or orientation, the pattern can be separated using the property of the X-ray diffraction pattern.

Since PET used as a transparent substrate has different orientation in the stretching direction, light and shade can be formed in the same Debye ring. Specifically, when a two-dimensional X-ray diffraction pattern of PET, which is a transparent substrate, was measured, it was confirmed that the diffraction intensity of PET increased in the vertical direction of the film.

Therefore, in order to separate the diffraction pattern from the transparent substrate from the diffraction pattern of the blackened layer, when measuring the X-ray diffraction pattern of the sample, the sample to be measured is ψ = 40 deg. The X-ray diffraction measurement was carried out by tilting to

The measurement was performed using an X-ray diffractometer (Brucker model: D8 DISCOVER μ-HR). Phase identification was performed from the obtained X-ray diffraction pattern, and the main phase contained in the blackened layer was specified.
(4) EDS analysis The EDS analysis was performed under the same conditions except that the conductive substrate production conditions shown in each experimental example, the thickness of the blackened layer was 500 nm, and the copper layer was not formed. SEM-EDS apparatus (SEM: manufactured by JEOL Ltd. Model: JSM-7001F, EDS: manufactured by Thermo Fisher Scientific Co., Ltd. Model: Detection) This was carried out using a device UltraDry analysis system NORAN System 7).
(Sample preparation conditions)
The manufacturing conditions of the conductive substrate in each experimental example are shown below. Experimental examples 2-3 to 2-7 are examples, and experimental examples 2-1 and 2-2 are comparative examples.
[Experimental Example 2-1]
A conductive substrate having the structure shown in FIG.

Specific conditions for sputtering will be described below.

A nickel-tungsten alloy target containing 19% by weight of tungsten and the balance being nickel was used as the target. Sputtering was performed while supplying argon into the chamber so as to have 15 SCCM. The ultimate vacuum in the chamber before sputtering was 1 × 10 ⁻³ Pa.

The blackened layer 13 having a thickness of 30 nm was formed by the sputtering method. For convenience of explanation, the layer formed is described as the blackened layer 13, but the layer formed as described later is a layer having Ni as a main phase and has a metallic luster. The blackening layer 13 does not function.

The reflectance measurement and the dissolution test were performed on the conductive substrate obtained by the above steps. Table 2 shows the reflectance and the evaluation results of the dissolution test.

In addition, a specific resistance measurement sample for measuring the specific resistance and evaluating the composition of the blackened layer was prepared.

As a sample for measuring specific resistance and the like, a transparent base material 11 made of polyethylene terephthalate resin (PET) having a length of 5 cm, a width of 5 cm, and a thickness of 0.02 mm was used. Then, the blackened layer 13 was formed on the entire surface of one surface of the transparent substrate 11 so as to have a film thickness of 500 nm, and the sample was prepared in the same manner as described above except that the copper layer 12 was not formed. It produced and used for evaluation.

Table 2 shows the measurement results of the specific resistance and the main phase of the blackened layer identified by the X-ray diffraction measurement.
[Experimental example 2-2]
When the blackening layer 13 is formed, nitrogen and argon are supplied into the chamber to a total of 15 SCCM, and each gas is supplied to the chamber so that 50% by volume of nitrogen and the remainder are argon. A conductive substrate and a sample for measuring specific resistance and the like were prepared in the same manner as in Experimental Example 2-1, except that sputtering was performed. Moreover, the produced sample was evaluated. In the present experimental example, the layer formed here is described as the blackened layer 13 for convenience of explanation, but the layer formed as the blackened layer 13 here does not contain oxygen and therefore reflects light. It was not a color that could be suppressed, and did not function as a blackened layer.

Table 2 shows the results of the dissolution test evaluation results, the specific resistance measurement results, and the main phase of the blackened layer identified by the X-ray diffraction measurement.
[Experimental Example 2-3]
When the blackening layer 13 is formed, nitrogen, oxygen, and argon are supplied into the chamber so that the total amount becomes 15 SCCM. The chamber is 45% by volume nitrogen, 5% by volume oxygen, and the balance is argon. A conductive substrate and a sample for measuring specific resistance and the like were prepared in the same manner as in Experimental Example 2-1, except that each gas was supplied and sputtering was performed. Moreover, the produced sample was evaluated.

Table 2 shows the results of the reflectance, the evaluation results of the dissolution test, the measurement results of the specific resistance, and the main phase of the blackened layer identified by the X-ray diffraction measurement.

Further, when EDS analysis was performed on the blackened layer of the measurement sample such as the specific resistance, it was confirmed that the blackened layer contained oxygen, nitrogen, nickel, and tungsten.
[Experimental Example 2-4]
When the blackening layer 13 is formed, nitrogen, oxygen, and argon are supplied into the chamber so that the total amount becomes 15 SCCM. The chamber is 30% by volume of nitrogen, 5% by volume of oxygen, and the balance is argon. A conductive substrate and a sample for measuring specific resistance and the like were prepared in the same manner as in Experimental Example 2-1, except that each gas was supplied and sputtering was performed. Moreover, the produced sample was evaluated.

Table 2 shows the results of the dissolution test evaluation results, the specific resistance measurement results, and the main phase of the blackened layer identified by the X-ray diffraction measurement.

Further, when EDS analysis was performed on the blackened layer of the measurement sample such as the specific resistance, it was confirmed that the blackened layer contained oxygen, nitrogen, nickel, and tungsten.
[Experimental Example 2-5]
When the blackening layer 13 is formed, nitrogen, oxygen, and argon are supplied into the chamber so that the total amount becomes 15 SCCM. The chamber is 40% by volume nitrogen, 10% by volume oxygen, and the balance is argon. A conductive substrate and a sample for measuring specific resistance and the like were prepared in the same manner as in Experimental Example 2-1, except that each gas was supplied and sputtering was performed. Moreover, the produced sample was evaluated.

Further, when EDS analysis was performed on the blackened layer of the measurement sample such as the specific resistance, it was confirmed that the blackened layer contained oxygen, nitrogen, nickel, and tungsten.
[Experimental Example 2-6]
When the blackening layer 13 is formed, nitrogen, oxygen, and argon are supplied into the chamber so that the total amount becomes 15 SCCM. The chamber is 37% by volume of nitrogen, 13% by volume of oxygen, and the balance is argon. A conductive substrate and a sample for measuring specific resistance and the like were prepared in the same manner as in Experimental Example 2-1, except that each gas was supplied and sputtering was performed. Moreover, the produced sample was evaluated.

Further, when EDS analysis was performed on the blackened layer of the measurement sample such as the specific resistance, it was confirmed that the blackened layer contained oxygen, nitrogen, nickel, and tungsten.
[Experimental Example 2-7]
When the blackening layer 13 is formed, nitrogen, oxygen, and argon are supplied into the chamber so that the total amount is 15 SCCM. The chamber is 10% by volume of nitrogen, 40% by volume of oxygen, and the balance is argon. A conductive substrate and a sample for measuring specific resistance and the like were prepared in the same manner as in Experimental Example 2-1, except that each gas was supplied and sputtering was performed. Moreover, the produced sample was evaluated.

Further, when the EDS analysis was performed on the blackened layer of the measurement sample such as the specific resistance, it was confirmed that the blackened layer contained oxygen, nitrogen, nickel, and tungsten.

According to the results shown in Table 2, all of Experimental Examples 2-1 to 2-7 were evaluated as ◯ or Δ in the dissolution test, and the copper layer and the blackened layer could be dissolved simultaneously. .

However, in Experimental Examples 2-1 and 2-2 which are comparative examples, the blackened layer 13 did not function as a blackened layer because it did not contain oxygen. Specifically, in Experimental Example 2-1, since the blackened layer does not contain nitrogen, metal Ni is the main phase of the blackened layer, has a metallic luster, and suppresses reflection of light. Did not have anything. In Experimental Example 2-2, since the layer formed as the blackened layer did not contain oxygen, it did not have a color capable of suppressing light reflection and did not function as a blackened layer. In Experimental Examples 2-1 and 2-2, the term blackened layer is used for convenience of explanation, but it did not function as a blackened layer as described above.

In order of Experimental Example 2-1 to Experimental Example 2-2 to Experimental Example 2-7, the film forming conditions for the blackened layer are selected such that the oxygen concentration when forming the blackened layer is increased. The main phase of the blackened layer identified by X-ray diffraction measurement for these experimental examples is that the metal Ni is black in Experimental Example 2-1, in which nitrogen and oxygen were not supplied when the blackened layer was formed. It is the main phase of the chemical layer. Then, in Experimental Example 2-2 and later in which nitrogen was supplied during the blackening layer formation, Ni ₃ N was observed as the main phase of the blackening layer, and the supply amount of oxygen during the blackening layer formation was further increased. In Experimental Examples 2-5 to 2-7, it was confirmed that the main phase of the blackened layer was changed to NiO.

In Examples 2-3 to 2-6, the specific resistance of the blackened layer is 2.00 × 10 ^{−2 in the} examples in which the oxygen concentration during film formation of the blackened layer is 15% by volume or less. It was confirmed that the resistance was as low as Ω · cm or less.

Although the conductive substrate and the method for manufacturing the conductive substrate have been described in the embodiments and examples, the present invention is not limited to the above-described embodiments and examples. Various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

This application is based on Japanese Patent Application No. 2013-227517 filed with the Japan Patent Office on October 31, 2013, and Japanese Patent Application No. 2014-075991 filed with the Japan Patent Office on March 31, 2014. The contents of Japanese Patent Application No. 2013-227517 and Japanese Patent Application No. 2014-075991 are incorporated herein by reference.

10A, 10B, 20A, 20B, 30, 60

Conductive substrate

11, 11A, 11B

Transparent base material

12, 12A,

12B Copper layer

13, 13A, 13B, 131, 132, 131A, 131B, 132A, 132B, 32A,

32B Blackening layer

31A, 31B Wiring

Claims

A transparent substrate;
A copper layer formed on at least one surface of the transparent substrate;
And a blackened layer formed on at least one surface of the transparent base material and containing oxygen, nitrogen, nickel, and tungsten.
The blackening layer is
Using a nickel-tungsten alloy target,
2. The conductive substrate according to claim 1, wherein the conductive substrate is formed by a sputtering method while supplying oxygen in a ratio of 5 to 20% by volume and nitrogen in a ratio of 30 to 55% by volume in the chamber.
The conductive substrate according to claim 2, wherein the target of the nickel-tungsten alloy contains tungsten in a proportion of 5 wt% to 30 wt%.
4. The conductive substrate according to claim 1, wherein the blackened layer has a specific resistance of 2.00 × 10 −2 Ω · cm or less.
The copper layer has a thickness of 50 nm or more,
The conductive substrate according to claim 1, wherein the blackened layer has a thickness of 15 nm or more.
The conductive substrate according to any one of claims 1 to 5, wherein the reflectance of light having a wavelength of 550 nm is 40% or less.
The electroconductive board | substrate as described in any one of Claims 1 thru | or 6 provided with the mesh-shaped wiring.
A transparent substrate preparation step of preparing a transparent substrate;
A copper layer forming step of forming a copper layer on at least one surface side of the transparent substrate;
And a blackening layer forming step of forming a blackening layer containing oxygen, nitrogen, nickel, and tungsten on at least one surface side of the transparent base material.
The blackening layer forming step includes
Using a nickel-tungsten alloy target,
9. The conductivity according to claim 8, wherein the blackened layer is formed by a sputtering method while supplying oxygen in a ratio of 5 volume% to 20 volume% and nitrogen in a ratio of 30 volume% to 55 volume% in the chamber. A method for manufacturing a substrate.
10. The method for manufacturing a conductive substrate according to claim 9, wherein the target of the nickel-tungsten alloy contains tungsten in a proportion of 5 wt% to 30 wt%.
The copper layer has a thickness of 50 nm or more,
The method for manufacturing a conductive substrate according to claim 8, wherein the blackened layer has a thickness of 15 nm or more.
The method for producing a conductive substrate according to any one of claims 8 to 11, wherein the obtained conductive substrate has a light reflectance of 40% or less at a wavelength of 550 nm.
Etching the copper layer and the blackened layer further includes an etching step of forming a wiring;
The manufacturing method of the conductive substrate as described in any one of Claims 8 thru | or 12 with which the conductive substrate obtained comprises a mesh-shaped wiring.