TW201631166A - Cu alloy film and cu multilayer film - Google Patents

Abstract

Proposed is a Cu alloy film which has low electrical resistance, excellent oxidation resistance and excellent wet etching workability. The Cu alloy film contains from 3.0 atom% to 19.0 atom% (inclusive) of Ni and one element X that is selected from the group consisting of Al, Zn, Mn and Sn, with the balance made up of Cu and unavoidable impurities. The content of the element X is x atom% or more that is determined by formula (1). In cases where the element X is Zn or Mn, the total content of Ni and the element X is 20.0 atom% or more, and in cases where the element X is Al or Sn, the total content of Ni and the element X is 16.0 atom% or more. x = 1.96 × Ni + 1.64 (1) (In formula (1), Ni represents the Ni content in atom% in the Cu alloy film).

Description

Copper alloy film, copper laminated film, wiring electrode, input device and touch panel sensor

The present invention relates to a copper alloy film and a copper laminate film.

In the past, an indium tin oxide (ITO) film or an aluminum film was used for a flat panel display such as a liquid crystal panel or an electroluminescence (EL) panel or a wiring of a touch panel. A wiring electrode using a film containing pure copper or a copper-based alloy has been proposed as the size of the panel is increased or the wiring is made finer, that is, narrower. However, since copper has high affinity with oxygen, it is oxidized by heating or time passage in the presence of oxygen, and causes discoloration or an increase in electrical resistance.

As a technique for using copper, Patent Document 1 proposes a sputtering target used when a protective film is formed on one surface or both surfaces of a copper wiring film. Specifically, the sputtering target contains 8.0% by mass or more and 11.0% by mass or less of aluminum, 3.0% by mass or more, and 5.0% by mass or less of iron, 0.5% by mass or more and 2.0% by mass or less of nickel, 0.5% by mass or more, and 2.0. Manganese with a mass of less than %, the remainder containing copper and unavoidable impurities. Further, Patent Document 1 discloses that a film formed by the sputtering target material is a protective film which is inhibited from discoloration during a weather resistance test in which the temperature is 60° C. and the relative humidity is 90% exposed for 250 hours.

Patent Document 2 discloses a copper alloy sputtering target which is characterized by containing 20.0% by mass to 40.0% by mass of nickel and adding 1.0% by mass to 10.0 mass in total as a copper alloy sputtering target. % of chromium, titanium, vanadium, aluminum, lanthanum, cobalt, zirconium, hafnium, molybdenum or two or more of these elements, and the remainder being copper and unavoidable impurities. Further, it has been revealed that the metal thin film formed by using the copper alloy sputtering target material is excellent in oxidation resistance and corrosion resistance as compared with copper or the like, and can be used as a protective film for a wiring material and a wiring material.

The applicant of the present application also proposes a wiring structure in a plasma processing apparatus using an oxide semiconductor layer in a plasma treatment using a gas containing oxygen atoms such as N ₂ O when forming a protective film. It can effectively prevent oxidation of copper wiring. In other words, a wiring structure including a semiconductor layer of a thin film transistor, a copper alloy film for an electrode, and a protective film including an oxide semiconductor, the copper layer, is provided in this order from the substrate side. The alloy film has a laminated structure including a first layer (X) and a second layer (Z) in this order from the substrate side, and in particular, the second layer (Z) contains a total of 2 atom% to 20 atom% selected from zinc, A copper-Z alloy of at least one Z group element of the group consisting of nickel, titanium, aluminum, magnesium, calcium, tungsten, lanthanum, rare earth elements, cerium, and manganese.

Patent Document 4 proposes a copper alloy wiring film for a touch panel sensor excellent in oxidation resistance, which is characterized in that a transparent conductive film and a wiring for a touch panel sensor connected to the transparent conductive film are provided. In the film, the wiring film has a laminated structure comprising a copper alloy containing at least one selected from the group consisting of alloy elements selected from the group consisting of nickel, zinc, and manganese in an amount of 0.1 atom% to 40 atom%. (first layer) and a second layer containing pure copper or a copper alloy containing copper as a main component and having a lower specific resistance than the first layer, and the second layer is connected to the transparent conductive film. [Prior Art Document] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. Open 2013-120411

[Problems to be solved by the invention]

However, when the copper-based film is patterned into a submicron size such as a wiring or the like, it is usually processed by a wet etching method. For example, in the wet etching process at the frame wiring of the touch panel sensor, an etching solution containing ferric chloride, an etching solution containing ammonium persulfate, an etching solution containing hydrogen peroxide, or containing phosphoric acid or acetic acid is used. A mixed acid etching solution such as nitric acid. However, the material proposed so far has a problem that a good wiring shape cannot be obtained by wet etching using the etching liquid. In particular, the copper-40 atom% nickel film shown in No. 7 of Table 1 of Patent Document 4 or the copper-20 atom% nickel-20 atom% manganese film shown in No. 29 is added in a large amount by nickel. Therefore, it has oxidation resistance, but does not increase the workability by the wet etching method, and microfabrication cannot be performed.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a copper alloy film which exhibits low electrical resistance and excellent oxidation resistance and can be satisfactorily processed by a wet etching method, and includes the copper alloy. A copper laminated film of a film, a laminated body having the copper laminated film, and a sputtering target for forming the copper alloy film. Hereinafter, the wiring process which can be favorably performed by the wet etching method is called "excellent wet etching processability". [Means for solving the problem]

The copper alloy film of the present invention which solves the above-mentioned problems is characterized in that it contains 3.0 atom% or more and 19.0 atom% or less of nickel, and contains one element selected from the group consisting of aluminum, zinc, manganese and tin. The remaining portion contains copper and unavoidable impurities, and the content of the X element is x atom% or more determined according to the following formula (1), and when the X element is zinc or manganese, nickel and X The total amount of the elements is 20.0 atom% or more, and when the X element is aluminum or tin, the total amount of nickel and X elements is 16.0 atom% or more. Hereinafter, the copper alloy film may be referred to as a "copper-nickel-X film", and a film containing a copper-based alloy in the first layer to be described later may be referred to as a "copper-based alloy film". x=1.96 × nickel + 1.64 (1) In the formula (1), nickel represents a nickel content in atomic % in the copper alloy film.

The copper laminated film of the present invention which solves the above-described problems is characterized by comprising a film containing a pure copper or a copper-based alloy as a first layer and the copper-nickel-X film as a second layer.

In a preferred embodiment of the present invention, the film thickness of the second layer is 10 nm or more and 200 nm or less.

In a preferred embodiment of the present invention, the copper-based alloy in the first layer comprises at least one Z element selected from the group consisting of titanium, manganese, iron, cobalt, nickel, niobium, and zinc. The remainder contains copper and unavoidable impurities.

In the present invention, a laminate having the copper laminated film on a substrate may be included. Further, in the present invention, a wiring electrode or an input device using the copper laminate film or the laminate, and a touch panel sensor may be included. Further, in the present invention, a copper alloy sputtering target for forming the copper-nickel-X film may be further included. [Effects of the Invention]

According to the present invention, it is possible to provide a copper-nickel-X film having low electric resistance and excellent oxidation resistance and wet etching workability, and oxidation resistance and wet type including the copper-nickel-X film as, for example, an oxidation resistant protective film. A copper laminated film excellent in etching workability; a laminated body having the copper laminated film; a wiring electrode or the like using the laminated body.

The inventors of the present invention have repeatedly worked hard to solve the problem. In order to obtain a copper alloy film which is excellent in oxidation resistance and excellent in wet etching processability based on copper which exhibits low electric resistance, in particular, alloy elements have been studied intensively.

As a result, it was found that a nickel-nickel containing 3.0 atom% or more and 19.0 atom% or less of nickel and containing an X element selected from the group consisting of aluminum, zinc, manganese, and tin is included in the range described below. The -X film can simultaneously achieve low resistance, excellent oxidation resistance, and excellent wet etching processability.

Hereinafter, the copper-nickel-X film will be described in detail.

First, it is explained from nickel. Nickel diffuses in the film and is thickened on the surface to be oxidized to form nickel oxide, and is passivated, thereby protecting the surface of the copper-nickel-X film and contributing to an improvement in oxidation resistance.

When the nickel content is less than 3.0 atomic%, even when the X element described later is contained, the oxidation resistance cannot be sufficiently ensured. Therefore, in the present invention, the nickel content is set to 3.0 atom% or more. Hereinafter, the nickel content may be simply referred to as the amount of nickel. The amount of nickel is preferably 4 atom% or more, more preferably 5.0 atom% or more, still more preferably 6.0 atom% or more. On the other hand, when the amount of nickel exceeds 19.0 atomic%, it is difficult to perform etching during wiring processing, and a good wiring shape cannot be obtained. Therefore, the amount of nickel is set to 19.0 atom% or less. The amount of nickel is preferably 12 atom% or less, more preferably 10 atom% or less.

Next, the X element will be described. Aluminum, zinc, manganese, and tin, which are elements of X, diffuse in the film, are thickened on the surface, are oxidized to form oxidation X, and are passivated, thereby protecting the surface of the copper-nickel-X film and contributing to resistance. Increased oxidative properties. Further, these elements are more easily dissolved in an etching liquid such as an etching solution containing ferric chloride than the nickel, and contribute to an improvement in wet etching processability.

Among the X elements, zinc and tin are elements having a low vapor pressure. Therefore, when a copper-nickel-X film is formed by a sputtering method, composition variation or the like is likely to occur as compared with aluminum or manganese. Therefore, from the viewpoint of easy use, as the X element, aluminum or manganese is preferably used.

In order to sufficiently exhibit the effect of the X element, the lower limit of the content of the X element in accordance with the amount of nickel is as follows. In other words, the content of the X element is made x% by atom or more based on the following formula (1). x=1.96×nickel +1.64 (1) In the formula (1), nickel represents a nickel content in atomic % in the copper-nickel-X film.

The upper limit of the content of the X element is not particularly limited. A preferred method for producing the copper-nickel-X film includes a sputtering method, and from the viewpoint of easiness of production of the sputtering target used in the sputtering method, The content of the X element is 50 atom% or less, more preferably 40 atom% or less, still more preferably 30 atom% or less.

Further, in the case of aluminum in the X element, the upper limit of the content is preferably 50 atom% or less. The reason for this is that if the amount of aluminum exceeds 50 atom%, the residue derived from alumina is likely to be generated during wiring processing, that is, the wet etching processability is liable to lower. The upper limit of the aluminum content is more preferably 40 atom% or less, still more preferably 30 atom% or less.

In the present invention, the lower limit of the total amount of nickel and X elements is defined in accordance with the type of the X element. When the X element is zinc or manganese, the amount of change in reflectance before and after heat treatment or the increase in eaves width during wiring processing in the wet etching method is suppressed, and excellent oxidation resistance or wet etching processing is ensured. From the viewpoint of properties, the total amount of nickel and X elements is 20.0 atom% or more. The total amount is preferably 25.0 atom% or more. On the other hand, from the viewpoint of easiness of production of the sputtering target for forming a thin film, the total amount is preferably 40.0 atom% or less.

Further, when the X element is aluminum or tin, the amount of change in reflectance before and after the heat treatment or the increase in the width of the ruthenium during the wiring processing in the wet etching method is suppressed, and excellent oxidation resistance or wet etching processability is ensured. In view of the above, the total amount of nickel and X elements is set to be 16.0 atom% or more. The total amount is preferably 20.0 atom% or more, and more preferably 25.0 atom% or more. On the other hand, the total amount is preferably 45.0 atom% or less, more preferably 43.0 atom% or less, and still more preferably 40.0 atom%, from the viewpoint of easiness of production of the sputtering target for forming a thin film. the following.

The copper-nickel-X film contains nickel in an amount of 3.0 at% or more and 19.0 at% or less, and is contained in a range corresponding to the lower limit of the amount of nickel as described above and the total amount of nickel is in the above range. An X element in the group consisting of aluminum, zinc, manganese and tin is selected, and the remainder contains copper and unavoidable impurities.

The film thickness of the copper-nickel-X film is not particularly limited. For example, it can be set to 10 nm or more and 200 nm or less. When a copper laminated film including the copper-nickel-X film is formed, it is recommended that the thickness of the copper-nickel-X film be as described later.

In the present invention, a copper laminated film obtained by laminating a film containing a pure copper or a copper-based alloy as a first layer and the copper-nickel-X film as a second layer is also included. In the copper laminated film, a copper-nickel-X film in which a first layer is formed as a conductive layer and a second layer is formed as an oxidation resistant protective film of the first layer is exemplified.

Hereinafter, the copper laminated film will be described in detail.

A film containing pure copper or a copper-based alloy was used as the first layer. Hereinafter, the "film containing pure copper or a copper-based alloy" may be referred to as "copper-based film". When the first layer is formed as the conductive layer, the first layer is preferably a copper-based film having a resistivity of 10 μΩ·cm or less, more preferably 5 μΩ·cm or less. The copper-based alloy film of the first layer includes at least one Z element selected from the group consisting of titanium, manganese, iron, cobalt, nickel, lanthanum, and zinc, and the remainder contains copper and inevitable impurities. Membrane. By including the Z element, various corrosion resistances or adhesion to the substrate are improved. These elements may be used singly or in combination of two or more. As shown in the examples to be described later, the desired oxidation resistance or wet etching processability in the present invention can be achieved by forming a predetermined second layer, and does not depend on the composition of the first layer. For example, the Z element may be contained in a range of more than 0 atomic % in total and 2 atomic % or less.

In order to sufficiently ensure oxidation resistance, the film thickness of the second layer is preferably 10 nm or more, and more preferably 30 nm or more. On the other hand, when the film thickness of the second layer is too thick, the composition of the second layer depends on the composition of the second layer, but the etching rate during wet etching is likely to be slower than that of the first layer, and as a result, the processed shape becomes a meandering shape. It is difficult to obtain excellent wet etching processability. Therefore, the film thickness of the second layer is preferably 200 nm or less, more preferably 100 nm or less.

The film thickness of the first layer is preferably 20 nm or more, and more preferably 50 nm or more, from the viewpoint of obtaining a film having a uniform film thickness or a uniform composition at the time of film formation. On the other hand, from the viewpoint of ensuring productivity, the film thickness of the first layer is preferably 500 nm or less, more preferably 400 nm or less.

The total film thickness of the first layer and the second layer is preferably 30 nm or more, and more preferably 50 nm or more. Further, the total film thickness is preferably 600 nm or less, more preferably 500 nm or less, and still more preferably 400 nm or less.

In the present invention, the laminate film having the copper laminate film, that is, the first layer and the second layer may be included on the substrate. Other layers such as an adhesion layer may be included in the laminate. Hereinafter, the form of the laminated body will be described while exemplifying the pattern.

Fig. 1 is a schematic cross-sectional view showing a configuration of a laminated body of the present invention. In FIG. 1, a film containing pure copper or a copper-based alloy as the first layer 1 is provided on the substrate 3, and a copper-nickel-X film as the second layer 2 is provided on the upper surface thereof, and the second layer is provided. 2 protect the first layer 1. In addition, examples of the substrate 3 include a glass substrate, a film substrate, a plastic substrate, a quartz substrate, and a tantalum substrate.

2 and 3 are schematic cross-sectional views showing a modification of the laminated body shown in Fig. 1. The substrate 3, the first layer 1 and the second layer 2 of FIGS. 2 and 3 are the same as those of FIG. 1, and each of the second layer 2 protects the first layer 1, that is, the second layer 2 has the outermost layer.

FIG. 2 shows a structure in which the adhesion layer 4 is provided between the substrate 3 and the first layer 1 in FIG. The adhesion layer 4 may be a normal user, and examples thereof include a titanium film having a film thickness of 5 nm to 30 nm, a molybdenum film, a nickel film, and a chromium film.

FIG. 3 shows a structure in which the adhesion layer 4 is provided between the substrate 3 and the first layer 1 in FIG. 1 and between the first layer 1 and the second layer 2. The adhesion layer 4 in FIG. 3 may be any conventional user, and examples thereof include a titanium film having a film thickness of 5 nm to 30 nm, a molybdenum film, a nickel film, and a chromium film.

The copper-nickel-X film is preferably formed by sputtering. When the sputtering method is used, a copper-nickel-X film having substantially the same composition as that of the sputtering target can be formed. As the sputtering method, for example, a direct current (DC) sputtering method, a radio frequency (RF) sputtering method, a magnetron sputtering method, a reactive sputtering method, or the like can be used, and the sputtering method can be formed. Conditions can be set as appropriate.

In the sputtering method, for example, when the copper-nickel-X film is formed, a copper alloy containing a predetermined amount of the nickel or X element and having a composition and a desired copper-nickel-X film are used. The same copper alloy sputtering target is preferable as the target material without forming a composition variation and forming a copper-nickel-X film having a desired composition and composition. Alternatively, two or more kinds of pure metal targets or alloy targets having different compositions may be used, and these may be simultaneously discharged to form a film. Alternatively, it is also possible to form a film by adjusting a component while plating a metal of an alloy element on a pure copper target.

When the copper-nickel-X film is formed by a sputtering method, the following conditions are exemplified as examples of the sputtering conditions. Sputtering condition film forming method: Sputtering film forming apparatus: CS-200 manufactured by ULVAC: substrate temperature: room temperature film forming gas: argon gas pressure: 2 mTorr sputtering power: 10 W to 500 W Vacuum reach: 1 × 10 ^-6 Torr or less

The shape of the copper alloy sputtering target of the present invention may be any shape depending on the shape or structure of the sputtering apparatus, and examples thereof include a square plate shape, a circular plate shape, and an annular plate shape. As a method for producing the copper alloy sputtering target, a method of obtaining an ingot containing a copper-based alloy by a dissolution molding method or a powder sintering method to obtain the copper alloy sputtering target material; or A preform comprising a copper-based alloy, that is, an intermediate before the final fine body is obtained, and the preform is densified by a densification mechanism to obtain an injection molding method of the copper alloy sputtering target. .

The film forming method of each layer other than the copper-nickel-X film can be suitably carried out by a method generally used in the technical field of the present invention.

The laminate having the copper-nickel-X film can be applied to a wiring electrode or an input device. The input device includes an input device having an input mechanism in the display device such as a touch panel, or an input device having no display device like a touch pad. The copper-nickel-X film of the present invention is particularly preferably used for a touch panel sensor.

The present application claims the benefit based on the priority of Japanese Patent Application No. 2015-030823, filed on Feb. 19, 2015, and Japanese Patent Application No. 2015-224068, filed on Nov. 16, 2015. The contents of the specification of Japanese Patent Application No. 2015-030823, filed on Feb. 19, 2015, and the contents of the specification of Japanese Patent Application No. 2015-224068, filed on Nov. In this application. [Examples]

In the following, the present invention will be specifically described by way of examples, but the present invention is not limited by the following examples, and may be appropriately modified and implemented in accordance with the scope of the foregoing and the following. All are included in the technical scope of the present invention. In other words, an etching liquid containing ferric chloride is used as the etching liquid for wet etching, but the etching liquid containing ammonium persulfate and an etching liquid containing hydrogen peroxide may be used. Or a mixed acid etching solution containing phosphoric acid, nitric acid or acetic acid.

(1) Preparation of laminated body sample As a transparent substrate, an alkali-free glass plate having a diameter of 4 Å and a thickness of 0.7 mm was prepared, and the following Table 2 to Table 4 were used by DC magnetron sputtering. The first layer and the second layer of the copper laminate film are formed on the alkali-free glass plate. Specifically, in Table 2, a copper laminated film including a pure copper film as the first layer and a copper-nickel-X film as the second layer was formed. In Table 3, various copper-based alloy films as the first layer and a copper-nickel-aluminum film containing 6.4 at% of nickel and 29.3 at% of aluminum as the second layer were formed. In Table 4, a pure copper film as a first layer and a copper-nickel-aluminum film containing 6.4 at% of nickel and 29.3 at% of aluminum as a second layer were formed, and each of the first layer and the second layer was formed. The film thickness changes. Further, in order to measure the specific resistance of the first layer, a sample in which only the copper-based film described in Table 1 was formed on the alkali-free glass plate was prepared.

At the time of film formation, the environment in the reaction chamber is temporarily adjusted to reach a degree of vacuum [vacuum arrival degree]: 3 × 10 ^-6 Torr before film formation, and then in the order of the first layer and the second layer on the substrate. Sputtering was performed under the sputtering conditions to form a copper clad film. As a sputtering target, a pure copper sputtering target or a disk-shaped sputtering target having the same composition as each copper-nickel-X film or each copper-based alloy film of the first layer and having a diameter of 4 吋 is used. . The following evaluation was performed using the sample having the copper laminated film.

Sputtering conditions Film forming method: Sputtering film forming apparatus: CS-200 manufactured by Aifike Co., Ltd. Temperature: room temperature Film forming gas: Argon gas pressure: 2 mTorr Sputtering power: 10 W to 500 W Vacuum reaching degree : 1 × 10 ^-6 Torr or less

(2) Measurement of Resistivity of First Layer The specific resistance of the first layer in the copper clad film was measured as follows. That is, a sample in which only the copper-based film described in Table 1 was formed on the alkali-free glass plate was used, and the specific resistance was measured by a four-terminal method. The results are shown in Table 1. In the present embodiment, those having a specific resistance of 1.0 × 10 ^-5 Ω·cm or less were regarded as pass, and those having a specific resistance of more than 1.0 × 10 ^-5 Ω·cm were regarded as unacceptable. Further, in Table 1, for example, "3.0E-06" of No. 1 indicates 3.0 × 10 ^-6 . The same applies to the values of sheet resistances in Tables 2 to 4 below.

[Table 1]

As is clear from Table 1, the resistivity of the film containing the pure copper or the copper-based alloy used as the first layer in the present embodiment was 1.0 × 10 ^-5 Ω·cm or less.

(3) Measurement of the amount of change in reflectance before and after the heat treatment In order to evaluate the oxidation resistance, the amount of change in reflectance before and after the heat treatment was measured by using the sample having the copper laminate film as follows. Namely, the reflectance at a wavelength of 550 nm was measured by a spectrophotometer manufactured by JASCO Corporation, V-570, using the sample immediately after the film formation, and used as a pre-heat treatment reflectance. Then, using a infrared lamp heating device manufactured by Aiko Co., Ltd.: RTP-6, the sample having the reflectance before the heat treatment was subjected to heat treatment at 150 ° C for 1 hour under the atmosphere. Using this heat-treated sample, the reflectance at a wavelength of 550 nm was measured in the same manner as described above, and used as a reflectance after heat treatment.

Further, the value obtained by subtracting the reflectance after the heat treatment from the reflectance before the heat treatment is referred to as "the amount of change in reflectance before and after the heat treatment". The results are shown in Tables 2 to 4. In the present embodiment, the amount of change in reflectance before and after the heat treatment is 15% or less, and it is considered to be excellent as oxidation resistance, and the amount of change in reflectance exceeding 15% is set as an oxidation resistance. Not qualified.

(4) Measurement of the width of the ruthenium or the width of the undercut during the wet etching process In order to evaluate the wet etching processability, the sample having the copper laminate film was subjected to the wiring process by wet etching as described below. Then, the width of the etching residue such as a flaw after the wiring processing was measured.

Specifically, in the present embodiment, an etching solution obtained by diluting Pureetch F108 manufactured by ITS Pure Chemical Industries, Ltd., which contains ferric chloride, by 10 times with pure water was used to etch the sample. Then, the cross-sectional shape and the planar shape of the sample subjected to the etching process were observed using an electron microscope: S-4000 manufactured by Hitachi Power Solutions. In addition, in the cross-sectional shape, the portion where the second layer remains longer than the first layer is judged as "檐", and the portion where the second layer becomes shorter than the first layer is judged as "side etching". "." Further, in the planar shape, the width of the ridge or the width of the undercut was calculated. At this time, the width of the ridge was determined as a positive number, and the width of the undercut was determined as a negative number. The results are shown in Tables 2 to 4.

Further, in the present embodiment, the 檐 width is 5.0 μm or less, or the wiring shape is side etching, that is, "the width of the ridge or the width of the side etching when the wiring is processed by the wet etching method" in Tables 2 to 4 The value of the negative value was determined to be excellent as wet etching workability, and the case where the 檐 width was more than 5.0 μm was unsatisfactory as wet etching workability.

(5) Measurement of sheet resistance of copper laminated film The sheet resistance of the copper laminated film was measured by the following method. Namely, a sample having the copper laminated film was used, and the sheet resistance was measured by a four-terminal method. The results are shown in Tables 2 to 4. Further, in the present embodiment, the sheet resistance was 10 Ω/□ or less, and the sheet resistance was set to be low, and the sheet resistance was higher than 10 Ω/□. In Tables 2 to 4, the sheet laminated film of any of the examples has a sheet resistance of 10 Ω/□ or less. This is considered to be because a low-resistance copper-based film is used as the first layer.

[Table 2]

The following are known from Table 2. No. 1, No. 8, and No. 13 are examples in which the second layer contains copper and nickel and does not contain an X element. In these examples, the 檐 width was increased and the wet etching processability was poor. No. 1 and No. 8 further resulted in poor oxidation resistance.

No. 2 to No. 7 and No. 9 to No. 12 in Table 2 are examples of a copper-nickel-aluminum film containing nickel and aluminum as an X element in the second layer.

In these examples, No. 2 is insufficient in the amount of nickel in the second layer, and the total amount of nickel and X elements is also insufficient, so that oxidation resistance is not good. Further, in No. 3 and No. 9, the second layer contains aluminum as the X element, but the content thereof is insufficient. In No. 3, the total amount of nickel and the X element is also insufficient, so that the oxidation resistance is not good. In No. 9, it became a result that the width of the crucible became large and the wet etching processability was also poor. In No. 12, since the amount of nickel in the second layer was excessive, the 檐 width became large and the wet etching processability was poor. On the other hand, No. 4 to No. 7, No. 10, and No. 11 of Table 2 are examples in which the requirements specified in the present invention are satisfied, and excellent oxidation resistance and wet etching workability are exhibited.

No. 14 to No. 18 in Table 2 are examples of a copper-nickel-manganese film containing nickel and manganese as the X element in the second layer.

In these examples, No. 14 and No. 15 contain manganese as the X element, but the content thereof is insufficient, and the total amount of nickel and X element is also insufficient, so that oxidation resistance is not good. On the other hand, No. 16 to No. 18 of Table 2 are examples in which the requirements specified in the present invention are satisfied, and excellent oxidation resistance and wet etching processability are exhibited.

No. 19 to No. 21 in Table 2 are examples of a copper-nickel-tin film containing nickel and tin as an X element in the second layer.

In these examples, although No. 19 contains tin as the X element in the second layer, the content is insufficient, so that the oxidation resistance is not good. On the other hand, No. 20 and No. 21 of Table 2 are examples in which the requirements specified in the present invention are satisfied, and excellent oxidation resistance and wet etching workability are exhibited.

[table 3]

In Table 3, the second layer was fixed to a copper-nickel-aluminum film containing 6.4 at% of nickel and 29.3 at% of aluminum, and the first layer was made into various copper-based alloy films, and the composition of the first layer was confirmed. The effect of the characteristics of the copper laminate film.

According to the results of Table 3, although various copper-based alloy films were used as the first layer, excellent oxidation resistance and wet etching workability were obtained in either case. From these results, it is understood that the oxidation resistance and the wet etching processability of the copper laminated film are mainly caused by the composition of the second layer as the oxidation resistant protective layer, and various copper bases are used even in the first layer. The properties of the alloy film will not change.

[Table 4]

In Table 4, the first layer was fixed to a pure copper film, and the second layer was fixed to a copper-nickel-aluminum film containing 6.4 at% of nickel and 29.3 at% of aluminum, and the first layer and the second layer were The film thickness was changed, and the film thickness dependence of each layer was confirmed. As a result, as in the case of No. 1 in Table 4, when the film thickness of the second layer exceeds the recommended upper limit of 200 nm, the width of the wet etching process cannot be sufficiently reduced, and good wet etching cannot be obtained. Sex. Further, as in the case of No. 7 in Table 4, when the film thickness of the second layer is lower than the recommended lower limit of 10 nm, the amount of change in reflectance before and after the heat treatment becomes large, and sufficient oxidation resistance cannot be ensured. On the other hand, as in the case of No. 2 to No. 6 and No. 8 to No. 11, in the example in which the film thickness of the second layer is within the recommended range, sufficient oxidation resistance and wetness can be obtained. Etching processability.

1‧‧‧A film containing a pure copper or copper-based alloy as the first layer
2‧‧‧ as the second layer of copper-nickel-X film
3‧‧‧Substrate
4‧‧ ‧ close layer

Fig. 1 is a schematic cross-sectional view showing a configuration of a laminated body of the present invention. Fig. 2 is a schematic cross-sectional view showing another configuration of the laminated body of the present invention. Fig. 3 is a schematic cross-sectional view showing another configuration of the laminated body of the present invention.

1‧‧‧A film containing a pure copper or copper-based alloy as the first layer

2‧‧‧ as the second layer of copper-nickel-X film

3‧‧‧Substrate

Claims (10)

A copper alloy film comprising: 3.0 at% or more and 19.0 at% or less of nickel, and comprising an X element selected from the group consisting of aluminum, zinc, manganese, and tin, the remainder comprising copper and not being The impurity to be avoided, and the content of the X element is x atom% or more determined according to the following formula (1), and when the X element is zinc or manganese, the total amount of nickel and X element is 20.0 atom. % or more, when the X element is aluminum or tin, the total amount of nickel and X element is 16.0 atom% or more, x=1.96×nickel +1.64·(1), in the formula (1), nickel represents The nickel content in atomic % in the copper alloy film. A copper laminate film comprising: a film comprising a pure copper or a copper-based alloy as a first layer; and a copper alloy film according to the first aspect of the invention as a second layer. The copper laminate film according to the second aspect of the invention, wherein the second layer has a film thickness of 10 nm or more and 200 nm or less. The copper laminate film according to claim 2, wherein the copper-based alloy in the first layer comprises at least one selected from the group consisting of titanium, manganese, iron, cobalt, nickel, ruthenium, and zinc. A Z element with the remainder containing copper and unavoidable impurities. A wiring electrode using the copper laminated film according to item 2 of the patent application. A wiring electrode using the copper laminated film as described in claim 4 of the patent application. An input device using the copper laminate film as described in claim 2 of the patent application. An input device using the copper laminate film as described in claim 4 of the patent application. A touch panel sensor using the copper laminate film as described in claim 2 of the patent application. A touch panel sensor using the copper laminate film as described in claim 4 of the patent application.