TW202414440A - Conductive film and method for manufacturing conductive film - Google Patents

Abstract

A conductive film (1) includes: an organic resin base material (2); an inorganic layer (3) disposed on one side in the thickness direction of the organic resin base material (2); and a copper layer (4) disposed directly on one side in the thickness direction of the inorganic layer (3). Y calculated from a predetermined relational expression is less than 23.200.

Description

Conductive film and method for producing the same

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

Previously, a conductive film having a substrate and a metal layer in sequence has been known. Such a conductive film is used as a conductive layer for forming a pattern of electrodes in various devices such as flat panel displays and touch panels.

Such a conductive film is produced, for example, by disposing a metal layer on one surface in the thickness direction of a substrate using a sputtering method.

On the other hand, during the production of the above-mentioned conductive film, outgassing from the substrate may occur. This outgassing may cause metal oxide to form on the other side of the metal layer in the thickness direction. This may result in a poor adhesion between the substrate and the metal layer.

In response to this, the industry is researching a conductive film with a barrier layer (anti-rust layer) between the substrate and the metal layer. The barrier layer can block outgassing from the substrate, thus eliminating the above-mentioned undesirable condition.

As such a conductive film, a conductive film including a resin film, an anti-rust layer, and a copper layer in sequence has been proposed (for example, refer to Patent Document 1). [Prior Art Document] [Patent Document]

[Patent Document 1] Japanese Patent Publication No. 2017-100368

[Problem to be solved by the invention] On the other hand, when a barrier layer is provided, there is a disadvantage that the specific resistance of the metal layer becomes higher. Specifically, when the metal layer is a copper layer, in particular, when the barrier layer is provided, the crystal growth of the (200) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method is hindered. As a result, the grain size becomes smaller and the grain boundaries that hinder the transfer of electrons increase. As a result, there is a disadvantage that the specific resistance becomes higher.

The present invention aims to provide a conductive film having an inorganic layer that blocks outgassing from an organic resin substrate and having a relatively low specific resistance, and a method for manufacturing the conductive film. [Technical means for solving the problem]

The present invention [1] is a conductive film comprising: an organic resin substrate; an inorganic layer disposed on one side of the organic resin substrate in the thickness direction; and a copper layer disposed directly on one side of the inorganic layer in the thickness direction; wherein Y calculated by the following formula (1) is less than 23.200. Y = -0.0002243 × (α ₁₁₁ / t) + 5.764 × _{β 111} -0.02178 × γ ₁₁₁ -0.02283 × (α ₂₀₀ / t) -0.009098 × _{γ 200} + 0.01051 × t + 28.15 (1) (In the above formula (1), α ₁₁₁ represents the integrated intensity of the peak of the (111) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method; t represents the thickness of the copper layer (nm); β ₁₁₁ represents the integrated intensity ratio of the integrated intensity of the peak of the (111) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method to the integrated intensity of all peaks of the copper layer; γ ₁₁₁ represents the crystallite size of the (111) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method (Å); α ₂₀₀ represents the integrated intensity of the peak of the (200) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method; γ ₂₀₀ represents the crystallite size of the (200) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method (Å)

The present invention [2] comprises the conductive film described in the above [1], wherein the thickness of the copper layer is greater than 50 nm.

The present invention [3] comprises the conductive film described in the above [1] or [2], wherein the thickness of the copper layer is less than 300 nm.

The present invention [4] comprises the conductive film described in any one of [1] to [3] above, wherein the thickness of the inorganic layer is not less than 2 nm and not more than 15 nm.

The present invention [5] is a method for manufacturing a conductive film, which comprises: a first step of preparing an organic resin substrate; a second step of disposing an inorganic layer on one side of the organic resin substrate in the thickness direction by sputtering; and a third step of disposing a copper layer on one side of the inorganic layer in the thickness direction by sputtering; at least one of the second step and the third step comprises supplying oxygen as a sputtering gas while supplying an inert gas.

The present invention [6] includes the method for manufacturing a conductive film described in the above [5], wherein in the above second step, oxygen gas is supplied as a sputtering gas while supplying an inert gas, and the flow rate of the above oxygen gas in the above second step is not less than 5 sccm and not more than 200 sccm.

The present invention [7] includes a method for manufacturing a conductive film as described in [5] above, wherein in the above step 3, oxygen is supplied as a sputtering gas simultaneously with the supply of an inert gas, and the above step 3 comprises: a step 3A, which utilizes a sputtering method to supply oxygen together with the inert gas to arrange a first copper layer on one side in the thickness direction of the inorganic layer; and a step 3B, which utilizes a sputtering method to supply an inert gas without supplying oxygen to arrange a second copper layer on one side in the thickness direction of the above first copper layer; and the flow rate of the oxygen gas in the above step 3A is not less than 1 sccm and not more than 20 sccm.

The present invention [8] includes a method for manufacturing a conductive film as described in [5], wherein in the second and third steps, oxygen is supplied as a sputtering gas while supplying an inert gas, and the third step comprises: a step 3A, which is to supply oxygen together with the inert gas by sputtering, and to arrange a first copper layer on one side of the inorganic layer in the thickness direction; and a step 3B, which is to supply an inert gas without supplying oxygen by sputtering, and to arrange a second copper layer on one side of the first copper layer in the thickness direction; and the flow rate of the oxygen in the second step is not less than 10 sccm and not more than 200 sccm, and the flow rate of the oxygen in the third step is less than the flow rate of the oxygen in the second step and is 1 sccm or more and 20 sccm or less. [Effect of the invention]

The conductive film of the present invention has an inorganic layer. Therefore, when manufacturing the conductive film, outgassing from the organic resin substrate can be blocked. As a result, the decrease in adhesion between the organic resin substrate (inorganic layer) and the copper layer can be suppressed.

In addition, the Y calculated by the specific relationship of the conductive film is less than 23.200. Therefore, the specific resistance of the copper layer can be reduced.

In the method for manufacturing a conductive film of the present invention, in at least one of the second step and the third step, oxygen is supplied as a sputtering gas while supplying an inert gas. Therefore, a conductive film having a copper layer with a lower specific resistance can be manufactured.

One embodiment of the conductive film of the present invention is described with reference to FIG. 1 .

In FIG1 , the up-down direction on the paper is the up-down direction (thickness direction). Also, the upper side on the paper is the upper side (one side in the thickness direction). Also, the lower side on the paper is the lower side (the other side in the thickness direction). Also, the left-right direction on the paper and the depth direction are the plane directions orthogonal to the up-down direction. Specifically, the direction arrows in each figure shall prevail.

The conductive film 1 has a film shape (including a sheet shape) having a specific thickness. The conductive film 1 extends in a plane direction perpendicular to the thickness direction. The conductive film 1 has a flat upper surface and a flat lower surface.

As shown in FIG1 , the conductive film 1 includes an organic resin substrate 2, an inorganic layer 3 disposed on one side in the thickness direction of the organic resin substrate 2, and a copper layer 4 disposed directly on one surface in the thickness direction of the inorganic layer 3. Specifically, the conductive film 1 includes an organic resin substrate 2, an inorganic layer 3 disposed directly on the upper surface (one side in the thickness direction) of the organic resin substrate 2, and a copper layer 4 disposed directly on the upper surface (one surface in the thickness direction) of the inorganic layer 3.

The thickness of the conductive film 1 is, for example, 300 μm or less, preferably 200 μm or less, and, for example, 1 μm or more, preferably 5 μm or more.

<Organic resin substrate> The organic resin substrate 2 has a film shape. The organic resin substrate 2 has flexibility. The organic resin substrate 2 is arranged on the entire lower surface of the inorganic layer 3 in contact with the lower surface of the inorganic layer 3. The organic resin substrate 2 is the lowermost layer of the conductive film 1.

As the organic resin substrate 2, for example, a polymer film can be cited.

Examples of materials for polymer films include polyester resins, (meth) acrylic resins, olefin resins, polycarbonate resins, polyether resins, polyarylate resins, melamine resins, polyamide resins, polyimide resins, cellulose resins, and polystyrene resins. Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. Examples of (meth) acrylic resins include polymethyl methacrylate. Examples of olefin resins include polyethylene, polypropylene, and cycloolefin polymers. Examples of cellulose resins include triacetyl cellulose.

As the material of the polymer film, polyester resin is preferably exemplified, and as the material of the polymer film, polyethylene terephthalate is more preferably exemplified.

The thickness of the organic resin substrate 2 is, for example, 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and, for example, 200 μm or less, preferably 150 μm or less, more preferably 100 μm or less.

The thickness of the organic resin substrate 2 can be measured using a pin gauge (manufactured by PEACOCK, "DG-205").

The organic resin substrate 2 is preferably transparent. Specifically, the total light transmittance (JIS K 7375-2008) of the organic resin substrate 2 is, for example, 80% or more, preferably 85% or more.

<Inorganic layer> The inorganic layer 3 is a layer used to block outgassing from the organic resin substrate 2 in the manufacturing method of the conductive film 1 described below.

The inorganic layer 3 has a film shape and is disposed on the entire upper surface of the organic resin substrate 2 so as to be in contact with the upper surface of the organic resin substrate 2. In addition, the inorganic layer 3 is disposed on the entire lower surface of the copper layer 4 so as to be in contact with the lower surface of the copper layer 4.

In addition, the inorganic layer 3 is formed by sputtering and is therefore a sputtering layer, which will be described in detail later.

The material of the inorganic layer 3 is not particularly limited as long as it is an inorganic substance other than copper. Specifically, preferred materials of the inorganic layer 3 include metals (except copper) and metal oxides (except copper oxide).

Examples of the metal include Ni, In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Pd, W, alloys thereof, and alloys thereof with copper. Preferably, the metal is CuNi.

Examples of the metal oxide include oxides of the above-mentioned metals. Preferred examples of the metal oxide include oxides containing indium. Examples of the indium-containing oxide include indium-tin composite oxide (ITO).

Furthermore, the metal oxide may be either crystalline or amorphous.

As the material of the inorganic layer 3, metal oxide is preferably exemplified.

The material of the inorganic layer 3 may be used alone or in combination of two or more.

The thickness of the inorganic layer 3 is, for example, 2 nm or more from the viewpoint of gas barrier properties, and is, for example, 15 nm or less from the viewpoint of processability, preferably 10 nm or less, and more preferably 7 nm or less.

Furthermore, the thickness of the inorganic layer 3 can be measured by observing the cross section of the conductive film 1 using a transmission electron microscope, for example.

<Copper layer> Copper layer 4 is a conductive layer. Copper layer 4 is formed into a desired pattern as needed.

The copper layer 4 has a film shape. The copper layer 4 is disposed on the entire upper surface of the inorganic layer 3 so as to be in contact with the upper surface of the inorganic layer 3. The copper layer 4 is the uppermost layer of the conductive film 1.

The copper layer 4 is formed by sputtering, and is therefore a sputtering layer, which will be described in detail later.

Examples of the material of the copper layer 4 include copper and copper alloys.

The metal constituting the copper alloy is not particularly limited, and examples thereof include silver, tin, chromium, and zirconium.

As a material of the copper layer 4, copper is preferably exemplified from the viewpoint of electrical conductivity. That is, the copper layer 4 is preferably composed of copper.

The specific resistance of the copper layer 4 is, for example, 2.300×10 ^-8 Ω·m or less, preferably 2.200×10 ^-8 Ω·m or less, more preferably 2.150×10 ^-8 Ω·m or less, further preferably 2.100×10 ^-8 Ω·m or less, particularly preferably 2.050×10 ^-8 Ω·m or less, and typically 1.000×10 ^-8 Ω·m or more.

Furthermore, the specific resistance can be calculated by multiplying the surface resistance value measured by the four-terminal method according to JIS K 7194 by the thickness of the copper layer 4.

The surface resistance of the copper layer 4 is, for example, 0.2200 Ω/□ or less, preferably 0.2000 Ω/□ or less, and more preferably 0.1500 Ω/□ or less.

The lower limit of the surface resistance value of the copper layer 4 is not particularly limited. For example, the surface resistance value of the copper layer 4 is usually greater than 0 Ω/□.

The surface resistance value can be measured using the four-terminal method according to JIS K 7194.

The thickness of the copper layer 4 is, for example, 50 nm or more, preferably 70 nm or more, more preferably 90 nm or more, and further preferably 100 nm or more from the viewpoint of resistance value. Also, for example, from the viewpoint of productivity, it is 300 nm or less, preferably 250 nm or less, more preferably 210 nm or less, further preferably 200 nm or less, particularly preferably 150 nm or less, and most preferably 120 nm or less.

Furthermore, the thickness of the copper layer 4 can be measured by, for example, cross-sectional TEM (Transmission Electron Microscopy) analysis.

<Method for manufacturing conductive film> The method for manufacturing the conductive film 1 is described with reference to FIGS. 2A to 2C and 3A to 3D.

The manufacturing method of the conductive film 1 comprises: a first step of preparing an organic resin substrate 2; a second step of disposing an inorganic layer 3 on one side of the organic resin substrate 2 in the thickness direction by sputtering; and a third step of disposing a copper layer 4 on one side of the inorganic layer 3 in the thickness direction by sputtering. In this method, each layer is sequentially disposed, for example, in a roll-to-roll manner. In this case, the conveying speed is, for example, 1.0 m/min or more, and, for example, 20.0 m/min or less.

In the method for manufacturing the conductive film 1, in the second step and the third step, the sputtering method is performed while supplying the sputtering gas, but in at least one of the second step and the third step, oxygen is supplied as the sputtering gas while supplying the inert gas (described below).

That is, in the method for manufacturing the conductive film 1, in the second step, oxygen is supplied along with the inert gas by sputtering to arrange the inorganic layer 3 on one surface in the thickness direction of the organic resin substrate 2, and/or, in the third step, oxygen is supplied along with the inert gas by sputtering to arrange the copper layer 4 on one surface in the thickness direction of the inorganic layer 3. Thus, the following formula (1) is satisfied.

In the following description, the first method, the second method, and the third method are described in detail, wherein the first method is to supply oxygen in the second step and not to supply oxygen in the third step, the second method is to not supply oxygen in the second step and to supply oxygen in the third step, and the third method is to supply oxygen in both the second step and the third step.

[Method 1] In method 1, oxygen is supplied in step 2, and oxygen is not supplied in step 3.

(Step 1) In step 1, as shown in FIG. 2A, an organic resin substrate 2 is prepared.

(Step 2) In step 2, as shown in FIG. 2B , an inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction by sputtering.

In order to arrange the inorganic layer 3 on one surface of the organic resin substrate 2 in the thickness direction by sputtering, first, the organic resin substrate 2 is subjected to a surface treatment in the thickness direction as required.

Examples of the surface treatment include corona treatment, plasma treatment, flame treatment, ozone treatment, primer treatment, glazing treatment, and saponification treatment.

Next, in the sputtering method, the target (material of the inorganic layer 3) and the organic resin substrate 2 are placed opposite to each other in a vacuum chamber of a sputtering film forming device. Then, by supplying a sputtering gas and applying a voltage from a power source, the gas ions are accelerated and irradiated to the target, so that the target material sputters out from the target surface. Then, the target material is deposited on the surface (one side in the thickness direction) of the organic resin substrate 2 to form the inorganic layer 3.

In addition, an inert gas (for example, argon) and oxygen are supplied as sputtering gases.

The flow rate of the oxygen gas is, for example, 5 sccm or more, preferably 30 sccm or more, more preferably 60 sccm or more, further preferably 80 sccm or more, particularly preferably 120 sccm or more, and, for example, 200 sccm or less.

Furthermore, the flow rate ratio of the inert gas to the oxygen gas is, for example, not less than 3.5 and, for example, not more than 200.

The gas pressure during sputtering is, for example, 0.1 Pa or more, preferably 0.2 Pa or more, and, for example, 2.0 Pa or less.

The power source may be, for example, any one of a DC (Direct Current) power source, an AC (Alternating Current) power source, an MF (Middle Frequency) power source, and an RF (Radio Frequency) power source, or a combination thereof.

The discharge output is, for example, 1.0 kW or more, preferably 10.0 kW or more, and, for example, 20 kW or less.

Thereby, the inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction.

(Step 3) In step 3, as shown in FIG. 2C , a copper layer 4 is disposed on one surface of the inorganic layer 3 in the thickness direction by sputtering.

In the sputtering method, the target (material of the copper layer 4) and the inorganic layer 3 are arranged opposite to each other in a vacuum chamber of a sputtering film forming device. Then, by supplying a sputtering gas and applying a voltage from a power source, the gas ions are accelerated and irradiated to the target, so that the target material sputters out from the target surface. Then, the target material is deposited on the surface (one side in the thickness direction) of the inorganic layer 3 to form the copper layer 4.

In addition, an inert gas was supplied as the sputtering gas, and oxygen was not supplied.

The gas pressure during sputtering is, for example, 0.1 Pa or more, preferably 0.2 Pa or more, and, for example, 2.0 Pa or less.

The power source may be, for example, any one of a DC power source, an AC power source, a MF power source, and an RF power source, or a combination thereof.

The discharge output is, for example, 10 kW or more, preferably 50 kW or more, and, for example, 150 kW or less.

The film formation temperature (the temperature of the organic resin substrate 2 on which the inorganic layer 3 is disposed) is, for example, 30° C. or higher and, for example, 60° C. or lower.

Thereby, the copper layer 4 is disposed on one surface of the inorganic layer 3 in the thickness direction.

The conductive film 1 is manufactured in the above manner.

[Method 2] In method 2, oxygen is not supplied in step 2, and oxygen is supplied in step 3.

In the third step, as a method of supplying oxygen, method 2A and method 2B can be cited as examples. In the method 2A, first, oxygen is supplied along with the inert gas by sputtering, and a portion of the copper layer 4 (hereinafter referred to as the first copper layer 4A) is arranged on one side in the thickness direction of the inorganic layer 3. Secondly, inert gas is supplied without oxygen by sputtering, and the remaining portion of the copper layer 4 (hereinafter referred to as the second copper layer 4B) is arranged on one side in the thickness direction of the first copper layer 4A. In the method 2B, oxygen is supplied along with the inert gas by sputtering, and the entire copper layer 4 is arranged on one side in the thickness direction of the inorganic layer 3.

The following describes the method 2A and the method 2B in detail.

[Method 2A] (Step 1) In step 1, as shown in FIG. 3A, an organic resin substrate 2 is prepared.

(Step 2) In step 2, as shown in FIG. 3B , an inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction by sputtering.

In the sputtering method, an inert gas is supplied as the sputtering gas, and oxygen is not supplied.

The gas pressure, power supply and discharge output during sputter plating are the same as those during sputter plating in step 2 of the first method described above.

Thereby, the inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction.

(Step 3) In step 3, the first copper layer 4A is arranged on one side of the inorganic layer 3 in the thickness direction by sputtering while supplying oxygen gas together with the inert gas. Then, the first copper layer 4B is arranged on one side of the first copper layer 4A in the thickness direction by sputtering while supplying inert gas without supplying oxygen gas.

That is, the third step comprises: a step 3A, which utilizes a sputtering method to supply oxygen along with an inert gas to configure a first copper layer 4A on one side in the thickness direction of the inorganic layer 3; and a step 3B, which utilizes a sputtering method to supply an inert gas without supplying oxygen to configure a second copper layer 4B on one side in the thickness direction of the first copper layer 4A.

In this case, the copper layer 4 includes a first copper layer 4A and a second copper layer 4B. The first copper layer 4A is formed by a sputtering method in which oxygen is supplied together with an inert gas, and the second copper layer 4B is formed by a sputtering method in which an inert gas is supplied but oxygen is not supplied.

(Step 3A) In step 3A, as shown in FIG. 3C, oxygen is supplied along with the inert gas by sputtering to arrange the first copper layer 4A on one surface in the thickness direction of the inorganic layer 3.

The flow rate of the oxygen gas is, for example, greater than 1 sccm, preferably greater than 3 sccm, more preferably greater than 7 sccm, and, for example, less than 20 sccm, preferably less than 15 sccm.

The flow rate ratio of the inert gas to the oxygen gas is, for example, 40 or more, and, for example, 150 or less.

The gas pressure, power supply and film forming temperature during the sputtering process are the same as those during the sputtering process in step 3 of the first method described above.

The discharge output is, for example, 5.0 kW or more, preferably 10.0 kW or more, and, for example, 20 kW or less.

Thereby, the first copper layer 4A is disposed on one surface of the inorganic layer 3 in the thickness direction.

The thickness of the first copper layer 4A is, for example, not less than 5 nm, and, for example, not more than 20 nm.

(Step 3B) In step 3B, as shown in FIG. 3D, a second copper layer 4B is disposed on one surface of the first copper layer 4A in the thickness direction by sputtering while supplying an inert gas and not supplying oxygen.

The gas pressure, power supply, discharge output and film forming temperature during sputtering are the same as those during sputtering in step 3 of the first method described above.

Thus, the second copper layer 4B is disposed on one surface of the first copper layer 4A in the thickness direction.

The thickness of the second copper layer 4B is, for example, not less than 50 nm, and, for example, not more than 300 nm.

Through the above, the copper layer 4 is arranged on one surface of the inorganic layer 3 in the thickness direction, thereby manufacturing the conductive film 1.

[Method 2B] (Step 1) In step 1, as shown in FIG. 2A, an organic resin substrate 2 is prepared.

(Step 2) In step 2, as shown in FIG. 2B , an inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction by sputtering.

In the sputtering method, an inert gas is supplied as a sputtering gas, and oxygen is not supplied.

The gas pressure, power supply and discharge output during sputter plating are the same as those during sputter plating in step 2 of the first method described above.

Thereby, the inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction.

(Step 3) In step 3, as shown in FIG. 2C, a copper layer 4 is disposed on one surface of the inorganic layer 3 in the thickness direction by sputtering while supplying oxygen gas along with the inert gas.

In this case, the copper layer 4 does not include a copper layer formed by a sputtering method in which an inert gas is supplied and oxygen is not supplied, but includes a copper layer formed by a sputtering method in which oxygen is supplied along with an inert gas.

The oxygen flow rate, the flow rate ratio of the inert gas to the oxygen flow rate, the gas pressure, the power supply, the discharge output and the film forming temperature during the sputtering are the same as those of the oxygen flow rate, the flow rate ratio of the inert gas to the oxygen flow rate, the gas pressure, the power supply, the discharge output and the film forming temperature during the sputtering in step 3A of the above method 2A.

Thereby, the copper layer 4 is disposed on one surface of the inorganic layer 3 in the thickness direction.

The conductive film 1 is manufactured in the above manner.

[Method 3] In method 3, oxygen is supplied in steps 2 and 3.

In addition, the third method is also the same. In the third step, as a method of supplying oxygen, the 3A method and the 3B method can be cited. In the 3A method, first, the sputtering method is used to supply oxygen together with the inert gas, and the first copper layer 4A is arranged on one side of the thickness direction of the inorganic layer 3. Secondly, the sputtering method is used to supply inert gas without supplying oxygen, and the second copper layer 4B is arranged on one side of the thickness direction of the first copper layer 4A. In the 3B method, the sputtering method is used to supply oxygen together with the inert gas, and the entire copper layer 4 is arranged on one side of the thickness direction of the inorganic layer 3.

The following describes the 3A method and the 3B method in detail.

[Method 3A] (Step 1) In step 1, as shown in FIG. 3A, an organic resin substrate 2 is prepared.

(Step 2) In step 2, as shown in FIG. 3B , an inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction by sputtering.

In the sputtering method, oxygen gas is supplied as a sputtering gas together with an inert gas.

The flow rate of the oxygen gas is, for example, greater than 10 sccm, preferably greater than 30 sccm, and, for example, less than 200 sccm, preferably less than 150 sccm, more preferably less than 100 sccm, further preferably less than 80 sccm, and particularly preferably less than 60 sccm.

The flow rate ratio of the inert gas to the oxygen gas is, for example, 40 or more, and, for example, 150 or less.

The gas pressure, power supply and discharge output during sputter plating are the same as those during sputter plating in step 2 of the first method described above.

Thereby, the inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction.

(Step 3A) In step 3A, as shown in FIG. 3C, oxygen is supplied along with the inert gas by sputtering to arrange the first copper layer 4A on one surface in the thickness direction of the inorganic layer 3.

The flow rate of oxygen gas is less than that of the second step of the above-mentioned method 3A, for example, 1 sccm or more, preferably 3 sccm or more, more preferably 5 sccm or more, and for example, 20 sccm or less, preferably 15 sccm or less, more preferably 8 sccm or less.

The flow rate ratio of the inert gas to the oxygen gas is, for example, 40 or more, and, for example, 500 or less.

The gas pressure, power supply, discharge output and film forming temperature during sputtering are the same as those during sputtering in step 3A of the above method 2A.

Thereby, the first copper layer 4A is disposed on one surface of the inorganic layer 3 in the thickness direction.

(Step 3B) In step 3B, as shown in FIG. 3D, a second copper layer 4B is disposed on one surface of the first copper layer 4A in the thickness direction by sputtering while supplying an inert gas and not supplying oxygen.

The gas pressure, power supply and discharge output during sputter plating are the same as those during sputter plating in step 3 of the first method described above.

Thus, the second copper layer 4B is disposed on one surface of the first copper layer 4A in the thickness direction.

Through the above, the copper layer 4 is arranged on one surface of the inorganic layer 3 in the thickness direction, thereby manufacturing the conductive film 1.

[Method 3B] (Step 1) In step 1, as shown in FIG. 2A, an organic resin substrate 2 is prepared.

(Step 2) In step 2, as shown in FIG. 2B , an inorganic layer 3 is disposed on one surface of the organic resin substrate 2 in the thickness direction by sputtering.

In the sputtering method, oxygen gas is supplied as a sputtering gas together with an inert gas.

The gas pressure, power supply and discharge output during sputter plating are the same as those during sputter plating in step 2 of the first method described above.

Thus, the inorganic layer 3 is arranged on one side of the thickness direction of the organic resin substrate 2. (Step 3) In the third step, as shown in FIG. 2C , the copper layer 4 is arranged on one side of the thickness direction of the inorganic layer 3 by supplying oxygen gas together with the inert gas using the sputtering method.

The oxygen flow rate, the flow rate ratio of the inert gas to the oxygen flow rate, the gas pressure, the power supply, the discharge output and the film forming temperature during the sputtering are the same as those of the oxygen flow rate, the flow rate ratio of the inert gas to the oxygen flow rate, the gas pressure, the power supply, the discharge output and the film forming temperature during the sputtering in step 3A of the above method 3A.

Thereby, the copper layer 4 is disposed on one surface of the inorganic layer 3 in the thickness direction.

The conductive film 1 is manufactured in the above manner.

As a method for manufacturing the conductive film 1, from the viewpoint of further reducing the specific resistance of the copper layer 4, the method 3A is preferably used.

<Y in the conductive film> In the conductive film 1, Y calculated by the following formula (1) is less than 23.200, preferably 23.000 or less, more preferably 22.500 or less, further preferably 22.000 or less, particularly preferably 21.500 or less, most preferably 21.000 or less, further preferably 20.500 or less, and for example, 10.000 or more. Y = -0.0002243 × (α ₁₁₁ / t) + 5.764 × β ₁₁₁ -0.02178 × γ ₁₁₁ -0.02283 × (α ₂₀₀ / t) -0.009098 × γ ₂₀₀ +0.01051 × t + 28.15 (1)

In the above formula (1), α ₁₁₁ represents the integrated intensity of the peak of the (111) plane of the copper layer 4 in the out-of-plane diffraction measurement by the X-ray diffraction method. The measurement method of the out-of-plane diffraction measurement by the X-ray diffraction method is described in detail in the following examples (the same applies hereinafter).

t represents the thickness of the copper layer 4 (nm).

β ₁₁₁ represents the integrated intensity ratio of the integrated intensity of the peak of the (111) plane of the copper layer 4 to the integrated intensity of all the peaks of the copper layer 4 in the out-of-plane diffraction measurement of the X-ray diffraction method. Furthermore, the so-called integrated intensity of all the peaks of the copper layer 4 refers to the total amount of the integrated intensity of the peak of the (111) plane, the integrated intensity of the peak of the (200) plane, the integrated intensity of the peak of the (311) plane, and the integrated intensity of the peak of the (222) plane.

γ ₁₁₁ represents the crystallite size (Å) of the (111) plane of the copper layer 4 in the out-of-plane diffraction measurement by the X-ray diffraction method. Specifically, the crystallite size of the (111) plane of the copper layer 4 is, for example, 400 Å or more, preferably 420 Å or more, more preferably 430 Å or more, and, for example, 500 Å or less, preferably 480 Å or less, more preferably 460 Å or less.

Furthermore, the crystallite size of the (111) plane of the copper layer 4 can be calculated using the Scherrer formula (crystal size = Kλ/βcosθ, K: Scherrer constant, λ: X-ray wavelength, β: half-value width, θ: Bragg angle) (the same applies below).

α ₂₀₀ represents the integrated intensity of the peak on the (200) plane of copper layer 4 in the out-of-plane diffraction measurement using the X-ray diffraction method.

γ ₂₀₀ represents the crystallite size (Å) of the (200) plane of the copper layer 4 in the out-of-plane diffraction measurement by the X-ray diffraction method. Specifically, the crystallite size of the (200) plane of the copper layer 4 is, for example, 200 Å or more, preferably 250 Å or more, more preferably 300 Å or more, and, for example, 400 Å or less, preferably 360 Å or less, and more preferably 340 Å or less.

In addition, the above formula (1) is derived based on the simulation described in detail in the following implementation.

In addition, Y can be adjusted to the above range by, for example, the flow rate of oxygen gas in the second step and the flow rate of oxygen gas in the third step.

<Effects> The conductive film 1 has the inorganic layer 3. Therefore, when the conductive film 1 is manufactured, outgassing from the organic resin substrate 2 can be blocked.

Specifically, during the production of the conductive film 2, outgassing from the organic resin substrate 2 may occur. This outgassing forms copper oxide on the other side of the copper layer 4 in the thickness direction. As a result, the adhesion between the organic resin substrate 2 and the copper layer 4 may be reduced.

On the other hand, the conductive film 1 has the inorganic layer 3. This can block the above-mentioned outgassing. In this way, the formation of copper oxide on the other side of the copper layer 4 in the thickness direction can be suppressed, and as a result, the decrease in the adhesion between the organic resin substrate 2 (inorganic layer 3) and the copper layer 4 can be suppressed.

In addition, Y calculated by the above formula (1) for the conductive film 1 is less than 23.200. Therefore, the specific resistance of the copper layer 4 can be reduced.

Specifically, as described above, from the perspective of suppressing the decrease in adhesion, when the inorganic layer 3 is provided, the crystal growth of the (200) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method is hindered. As a result, the crystal grains become smaller and the grain boundaries that hinder the transfer of electrons increase. As a result, the specific resistance becomes higher.

On the other hand, in the conductive film 1, Y calculated by the above formula (1) is less than 23.200. In this case, the crystal growth of the (200) plane in the copper layer 4 proceeds appropriately, and the crystal grains can be enlarged, thereby reducing the specific resistance of the copper layer 4.

<Variations> In the variations, the same reference symbols are used for the same components and steps as those in the first embodiment, and detailed descriptions thereof are omitted. In addition, unless otherwise specified, the variations can exert the same effects as those of the first embodiment. Furthermore, an embodiment and its variations can be appropriately combined.

In the above description, the conductive film 1 has an organic resin substrate 2, an inorganic layer 3, and a copper layer 4 in order in the thickness direction, but a functional layer (such as a hard coating layer) may be arranged between the organic resin substrate 2 and the inorganic layer 3. In this case, the conductive film 1 has an organic resin substrate 2, a hard coating layer, an inorganic layer 3, and a copper layer 4 in order in the thickness direction. [Example]

The following are examples and comparative examples to further illustrate the present invention. Furthermore, the present invention is not limited to the examples and comparative examples. In addition, the specific numerical values such as the blending ratio (content ratio), physical property values, and parameters used in the following description can be replaced by the corresponding upper limit values (defined as values "below" or "less than") or lower limit values (defined as values "above" or "exceeding") of the corresponding blending ratios (content ratios), physical property values, and parameters recorded in the above-mentioned "Implementation Method".

<Manufacturing of a conductive film> Example 1 A conductive film is manufactured by the first method. Specifically, a conductive film is manufactured according to the following procedure.

[Step 1] Prepare polyethylene terephthalate (125U48, manufactured by Toray Industries, Inc., thickness 125 μm) as an organic resin substrate.

[Step 2] Based on the following conditions, an inorganic layer (thickness 5 nm) is arranged on one side of the thickness direction of the organic resin substrate by sputter plating. {Conditions} Equipment: Roll-to-roll sputter plating device (roll-to-roll DC magnetron sputter plating device) Material of inorganic layer: ITO Gas: Argon and oxygen (oxygen flow rate 50 sccm), flow rate ratio of inert gas to oxygen flow rate 14 Discharge output: 7.2 kW Air pressure in film forming chamber: 0.4 Pa Travel speed: 8.0 m/min

[Step 3] Based on the following conditions, a copper layer (104.6 nm) was arranged on one side of the inorganic layer in the thickness direction by sputtering. {Conditions} Equipment: Roll-to-roll sputtering film forming device (roll-to-roll DC magnetron sputtering device) Gas: Argon Discharge output: 100 kW Air pressure in film forming chamber: 0.4 Pa Film forming temperature: 40°C Travel speed: 8.0 m/min

Example 2 to Example 5 A conductive film was manufactured based on the same sequence as Example 1. However, based on the description in Table 1, the inorganic layer, oxygen flow rate and copper layer thickness were changed.

Example 6 A conductive film is manufactured by the method 2A. Specifically, the conductive film is manufactured according to the following sequence.

[Step 1] Prepare polyethylene terephthalate (125U48, manufactured by Toray Industries, Inc., thickness 125 μm) as an organic resin substrate.

[Step 2] Based on the following conditions, an inorganic layer (thickness 5 nm) is arranged on one side of the thickness direction of the organic resin substrate by sputter plating. {Conditions} Equipment: Roll-to-roll sputter plating device (roll-to-roll DC magnetron sputter plating device) Material of the inorganic layer: ITO Gas: Argon Discharge output: 7.2 kW Air pressure in the film forming chamber: 0.4 Pa Travel speed: 8.0 m/min

[Step 3A] Based on the following conditions, the first copper layer (thickness 12 nm) is arranged on one side of the thickness direction of the inorganic layer by sputtering. {Conditions} Equipment: Roll-to-roll sputtering film forming device (roll-to-roll DC magnetron sputtering device) Gas: Argon and oxygen (oxygen flow rate 5 sccm), flow rate ratio of inert gas to oxygen flow rate 5 Discharge output: 14.7 kW Air pressure in film forming chamber: 0.4 Pa Film forming temperature: 40℃ Travel speed: 8.0 m/min

[Step 3B] Based on the following conditions, a second copper layer (thickness 92 nm) is disposed on one side of the first copper layer in the thickness direction by sputter plating. {Conditions} Equipment: Roll-to-roll sputter plating device (roll-to-roll DC magnetron sputter plating device) Gas: Argon Discharge output: 100 kW Air pressure in film forming chamber: 0.4 Pa Film forming temperature: 40°C Travel speed: 8.0 m/min

Example 7 A conductive film was manufactured based on the same sequence as Example 6. However, the flow rate of oxygen was changed based on the description in Table 1.

Example 8 A conductive film is manufactured by the 3A method. Specifically, the conductive film is manufactured according to the following sequence.

[Step 1] Prepare polyethylene terephthalate (125U48, manufactured by Toray Industries, Inc., thickness 125 μm) as an organic resin substrate.

[Step 2] Based on the following conditions, an inorganic layer (thickness 5 nm) is arranged on one side of the thickness direction of the organic resin substrate by sputter plating. {Conditions} Equipment: Roll-to-roll sputter plating device (roll-to-roll DC magnetron sputter plating device) Material of the inorganic layer: ITO Gas: Argon and oxygen (oxygen flow rate 20 sccm), flow rate ratio of inert gas to oxygen flow rate 35 Discharge output: 7.2 kW Air pressure in the film forming chamber: 0.4 Pa Travel speed: 8.0 m/min

[Step 3A] Based on the following conditions, the first copper layer (thickness 12 nm) is arranged on one side of the thickness direction of the inorganic layer by sputtering. {Conditions} Equipment: Roll-to-roll sputtering film forming device (roll-to-roll DC magnetron sputtering device) Gas: Argon and oxygen (oxygen flow rate 7 sccm), flow rate ratio of inert gas to oxygen flow rate 100 Discharge output: 14.7 kW Air pressure in film forming chamber: 0.4 Pa Film forming temperature: 40℃ Travel speed: 8.0 m/min

[Step 3B] Based on the following conditions, a second copper layer (thickness 92 nm) is disposed on one side of the first copper layer in the thickness direction by sputter plating. {Conditions} Equipment: Roll-to-roll sputter plating device (roll-to-roll DC magnetron sputter plating device) Gas: Argon Discharge output: 100 kW Air pressure in film forming chamber: 0.4 Pa Film forming temperature: 40°C Travel speed: 8.0 m/min

Example 9 to Example 13 A conductive film was manufactured based on the same sequence as Example 8. However, based on the description in Table 1, the flow rate of oxygen and the thickness of the copper layer were changed.

Comparative Example 1 A conductive film was manufactured based on the same sequence as in Example 1. However, the flow rate of oxygen was changed based on the description in Table 1. Specifically, in step 2, oxygen was not supplied.

<Evaluation> (Surface resistance) The surface resistance of the copper layer of each embodiment and each comparative example was measured by a four-terminal method in accordance with JIS K 7194. The results are shown in Table 1.

(Specific resistance) The specific resistance of the copper layer of each embodiment and each comparative example was calculated by multiplying the surface resistance value by the thickness of the copper layer. The results are shown in Table 1.

(Out-of-plane diffraction measurement by X-ray diffraction method) Out-of-plane diffraction measurement by X-ray diffraction method was performed on the metals of each embodiment and each comparative example under the following measurement conditions using an X-ray analyzer (SmartLab (manufactured by Rigaku)). The results of α ₁₁₁ , β ₁₁₁ , γ ₁₁₁ , α ₂₀₀ and γ ₂₀₀ obtained are shown in Table 1. {Measurement conditions} Scanning axis: 2θ/θ Starting angle (°): 10 End angle (°): 100 Step length (°): 0.02 Speed (/min): 1.0

(Calculation of Y) First, a conductive film is prepared to calculate the above formula (1) according to the following sequence, and out-of-plane diffraction measurement of the X-ray diffraction method is performed. In this way, 14 experimental data are obtained that establish a correlation between process conditions and the specific resistance value of the copper layer 4 (equivalent to the data of Example 1 to Example 13 and Comparative Example 1). Based on the experimental data obtained, various explanatory variables are created and ridge regression is performed. Ridge regression is a linear regression method with an L2 regularization term. By ridge regression, the coefficients of the formula are optimized to improve the prediction accuracy. In this way, the above formula (1) is obtained. Each parameter is substituted into the above formula (1) obtained to calculate Y. The results are shown in Table 1.

<Investigation> It can be seen that since Examples 1 to 13 have an inorganic layer, they can block outgassing from the organic resin substrate.

Furthermore, it is found that even when an inorganic layer is provided, Examples 1 to 13 in which Y is less than 23.200 can reduce the specific resistance compared to Comparative Example 1 in which Y is 23.200 or more.

Specifically, in Examples 1 to 13 where Y is less than 23.200, the specific resistance can be less than 2.300×10 ^-8 Ω·m. Specifically, it can be seen that the practicality of the specific resistance can be ensured to achieve a practical level for use as a conductive layer for patterning electrodes in various devices such as flat panel displays and touch panels.

[Table 1] Table 1 Example/Comparative Example No. method Inorganic layer Oxygen flow rate (sccm) The ratio of the inert gas flow rate to the oxygen flow rate Thickness of copper layer (nm) Y Specific resistance (Ω*m) Surface resistance (Ω/□) γ ₁₁₁ (Å) α ₁₁₁ /t β ₁₁₁ γ ₂₀₀ (Å) α ₂₀₀ /t Step 2 Step 3 Step 2 Step 3 Embodiment 1 Method 1 ITO 50 0 14 - 104.6 22.619 2.286×10 ^-8 0.2186 430.2 256.1 0.9333 264.4 7.76 Embodiment 2 Method 1 ITO 70 0 10 - 104.6 21.511 2.124×10 ^-8 0.2030 451.4 264.1 0.9250 322.6 10.72 Embodiment 3 Method 1 ITO 150 0 4.7 - 104.6 21.127 2.060×10 ^{- 8} 0.1969 450.8 156.5 0.8679 315.5 17.57 Embodiment 4 Method 1 CuNi 50 0 14 - 107.0 20.758 2.080×10 ^-8 0.1766 451.1 190.0 0.8552 331.6 24.61 Embodiment 5 Method 1 ITO 50 0 14 - 200.9 21.131 2.115×10 ^-8 0.1053 491.7 272.5 0.9127 361.1 14.72 Embodiment 6 Method 2A ITO 0 5 - 140 104.6 22.025 2.241×10 ^-8 0.2143 441.5 227.1 0.9211 289.5 10.18 Embodiment 7 Method 2A ITO 0 10 - 70 104.6 21.234 2.177×10 ^-8 0.2081 444.7 157.9 0.8709 321.0 17.23 Embodiment 8 Method 3A ITO 20 7 35 100 104.6 20.749 2.088×10 ^-8 0.1996 450.0 143.9 0.8467 339.2 20.22 Embodiment 9 Method 3A ITO 50 2 14 350 104.6 21.374 2.111×10 ^{- 8} 0.2019 447.7 216.8 0.9047 326.9 13.87 Embodiment 10 Method 3A ITO 50 7 14 100 103.3 20.269 2.019×10 ^{- 8} 0.1955 442.0 123.0 0.7626 322.8 33.78 Embodiment 11 Method 3A ITO 50 10 14 70 104.6 21.043 2.113×10 ^{- 8} 0.2020 437.3 111.3 0.8222 323.8 19.70 Embodiment 12 Method 3A ITO 70 7 10 100 104.6 20.902 2.068×10 ^{- 8} 0.1977 443.2 105.7 0.8208 326.1 19.04 Embodiment 13 Method 3A ITO 50 7 14 100 76.5 21.530 2.150×10 ^{- 8} 0.2810 394.3 86.6 0.7563 287.4 24.60 Comparison Example 1 - ITO 0 0 - - 104.6 23.335 2.332×10 ^{- 8} 0.2229 430.2 303.2 0.9518 209.0 2.69

Furthermore, the above invention is provided as an illustrative embodiment of the present invention, but it is only a simple example and should not be interpreted in a limiting sense. Variations of the present invention that are known to those skilled in the art are included in the scope of the following patent application. [Industrial Applicability]

The conductive film and the method for manufacturing the conductive film of the present invention are preferably used in the manufacture of various devices such as touch panels and photo sensors.

1: Conductive film 2: Organic resin substrate 3: Inorganic layer 4: Copper layer

FIG. 1 shows an implementation of the conductive film of the present invention. FIG. 2A to FIG. 2C show an implementation of the method for manufacturing the conductive film. FIG. 2A shows the first step of preparing an organic resin substrate. FIG. 2B shows the second step of configuring an inorganic layer on one side of the thickness direction of the organic resin substrate. FIG. 2C shows the third step of configuring a copper layer on one side of the thickness direction of the inorganic layer. FIG. 3A to FIG. 3D show an implementation of the method for manufacturing the conductive film. FIG. 3A shows the first step of preparing an organic resin substrate. FIG. 3B shows the second step of configuring an inorganic layer on one side of the thickness direction of the organic resin substrate. FIG. 3C shows the third step of configuring the first copper layer on one side of the thickness direction of the inorganic layer. FIG3D shows step 3B of configuring the second copper layer on one surface in the thickness direction of the first copper layer.

1: Conductive film

2: Organic resin substrate

3: Inorganic layer

4: Copper layer

Claims (8)

A conductive film comprising: an organic resin substrate; an inorganic layer disposed on one side of the organic resin substrate in a thickness direction; and a copper layer disposed directly on one side of the inorganic layer in a thickness direction; wherein Y calculated by the following formula (1) is less than 23.200, Y = -0.0002243 × (α ₁₁₁ / t) + 5.764 × β ₁₁₁ -0.02178 × γ ₁₁₁ -0.02283 × (α ₂₀₀ / t) -0.009098 × γ ₂₀₀ + 0.01051 × t + 28.15 (1) (In the above formula (1), α ₁₁₁ represents the integrated intensity of the peak of the (111) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method; t represents the thickness of the copper layer (nm); β ₁₁₁ represents the integrated intensity ratio of the peak of the (111) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method to the integrated intensity of all peaks of the copper layer; γ ₁₁₁ represents the crystallite size of the (111) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method (Å); α ₂₀₀ represents the integrated intensity of the peak of the (200) plane of the copper layer in the out-of-plane diffraction measurement of the X-ray diffraction method; γ ₂₀₀ represents the crystallite size of the (200) plane of the copper layer measured by out-of-plane diffraction using X-ray diffraction (Å). The conductive film of claim 1, wherein the thickness of the copper layer is greater than 50 nm. The conductive film of claim 1, wherein the thickness of the copper layer is less than 300 nm. The conductive film according to any one of claims 1 to 3, wherein the thickness of the inorganic layer is not less than 2 nm and not more than 15 nm. A method for manufacturing a conductive film comprises: a first step of preparing an organic resin substrate; a second step of configuring an inorganic layer on one side of the organic resin substrate in the thickness direction by sputtering; and a third step of configuring a copper layer on one side of the inorganic layer in the thickness direction by sputtering; and at least one of the second step and the third step comprises supplying oxygen as a sputtering gas while supplying an inert gas. A method for manufacturing a conductive film as claimed in claim 5, wherein in the above-mentioned second step, oxygen gas is supplied as a sputtering gas while supplying an inert gas; The flow rate of the above-mentioned oxygen gas in the above-mentioned second step is greater than 5 sccm and less than 200 sccm. A method for manufacturing a conductive film as claimed in claim 5, wherein in the above-mentioned step 3, oxygen is supplied as a sputtering gas while supplying an inert gas; The above-mentioned step 3 comprises: step 3A, which utilizes a sputtering method to supply oxygen together with the inert gas, and configures a first copper layer on one side in the thickness direction of the inorganic layer; and step 3B, which utilizes a sputtering method to supply an inert gas without supplying oxygen, and configures a second copper layer on one side in the thickness direction of the above-mentioned first copper layer; and The flow rate of oxygen in the above-mentioned step 3A is greater than 1 sccm and less than 20 sccm. A method for manufacturing a conductive film as claimed in claim 5, wherein in the above-mentioned second and third steps, oxygen is supplied as a sputtering gas while supplying an inert gas; The above-mentioned third step comprises: a step 3A, which utilizes a sputtering method to supply oxygen together with the inert gas, and configures a first copper layer on one side of the thickness direction of the inorganic layer; and a step 3B, which utilizes a sputtering method to supply an inert gas without supplying oxygen, and configures a second copper layer on one side of the thickness direction of the above-mentioned first copper layer; and The flow rate of oxygen in the above-mentioned second step is not less than 10 sccm and not more than 200 sccm; The flow rate of oxygen in the above-mentioned third step is less than the flow rate of oxygen in the above-mentioned second step, and is 1 sccm or more and 20 sccm or less.