TWI653349B - Cu alloy target material, Cu alloy target, Cu alloy film and touch panel - Google Patents

Abstract

The present invention relates to a material for a Cu alloy target having the following structure: (1) The material for a Cu alloy target includes Zn 0.1 to 10.0 at%, and further includes a material selected from the group consisting of Mg, At least one element in the group consisting of Cr, Ca, Ti, Al, Sn, Ni, and B, and the remainder contains Cu and unavoidable impurities; and (2) the aforementioned Cu alloy target material is used for A target for forming a Cu alloy film on a substrate, the Cu alloy film is used for a sensor electrode and / or wiring of a touch panel.

Description

Cu alloy target material, Cu alloy target, Cu alloy film and touch panel

The present invention relates to a material for a Cu alloy target, a Cu alloy target, a Cu alloy film, and a touch panel. More specifically, the present invention relates to a method for manufacturing a Cu alloy film with low specific resistance and excellent adhesion to a resin substrate. Materials for Cu alloy targets and Cu alloy targets; and Cu alloy films and touch panels manufactured using such Cu alloy targets.

The touch panel capable of inputting in the image display screen by using a sensor arranged in front of the screen display device is widely used in banks' automatic teller machines (ATM) or ticket vending machines due to its excellent usability. , Car navigation system, personal digital assistant (PDA, Personal Digital Assistant), operating images of photocopiers, etc., and in recent years it has also expanded to various screen devices such as mobile phones or tablet personal computers. Examples of the method include a resistive film method, an electrostatic capacitance method, an optical method, an ultrasonic surface acoustic wave method, and a piezoelectric method. Among these, the electrostatic capacitance method is used for mobile phones, tablet PCs, and the like because it can achieve multi-touch, excellent responsiveness, and low cost.

The capacitive touch sensor is a structure in which two types of transparent conductive films (sensors) pass through a glass substrate, a film substrate, an organic film, and a SiO ₂ film and are orthogonal to each other. Among them, resin-based film substrates such as polyethylene terephthalate (PET) are excellent in ease of handling. As a finger approaches the electrostatic capacitance between the conductive films that are sensors, the touched area is sensed. The high specific resistance of the transparent conductive film and the close contact with the base substrate become problems.

The current transparent conductive film has a large specific resistance, so it is difficult to achieve a large screen size. The reason is that if the screen is enlarged at the same specific resistance, the time for sensing the change in the electrostatic capacitance from the transparent conductive film becomes longer.

In addition, in a sensor using a transparent electrode, in addition to the transparent electrode layer, it is also necessary to repeatedly form and etch the adhesion layer, the conductive layer, and the protective layer. The restrictions on the film forming device and the complexity of the number of steps become problems. Therefore, the cost becomes higher, and it also imposes greater restrictions on manufacturers.

Furthermore, the price of ITO is high, so it is seeking low-cost materials.

Therefore, an alloy film that can function as both a sensor and a conductive layer has attracted attention. The film-forming alloy film replaces the transparent conductive film, and the front part of the image display device is made into a line width (texture pattern) that is invisible to the human eye, thereby simultaneously acting as a sensor and a conductive layer instead of a transparent electrode. If it is an alloy with excellent adhesion to the substrate, there is no need for a close contact layer, and the production can be completed after a layer of alloy film formation and etching, so the manufacturing steps can be greatly shortened.

Examples of the textured metal include Ag, Al, and Cu-based metals and alloys. Ag has the problem of higher material cost. The specific resistance of Al is higher than that of Ag and Cu. In addition, it is difficult to reduce the reflectance by heat treatment. Furthermore, Cu is a problem with the barrier ribs of the substrate. In addition, if it is a Cu alloy, the adhesion can be improved to some extent by adding an element, but if an alloy element is added to Cu, the specific resistance is greatly increased.

Patent documents 1 to 5 disclose Cu alloys having excellent adhesion. However, these are adhesion properties to glass substrates, oxides such as ITO, and semiconductors or ceramics such as Si, and there is no description of adhesion properties to resin films (PET, etc.).

Patent Document 6 discloses a Cu film having high adhesion to a transparent electrode as a wiring film for a touch panel. However, there is no description that a resin-based film (such as PET) required for layering of a Cu alloy is directly formed. Further, in Patent Document 6, it is preferable to set the specific resistance to 11.0 μΩ. cm or less, but thinned to a width of 10 μm or less for use as a sensor electrode. A lower specific resistance must be achieved. A component having both low specific resistance and adhesion to a resin-based film (such as PET) is required.

In addition, in Non-Patent Document 1, studies have been made on Cu alloys having high adhesion to glass substrates, and the adhesion to resin-based films (such as PET) is not described here.

Furthermore, in order to suppress flicker caused by natural light entering the screen of the touch panel or light reflection from electric lamps, the sensor electrodes need to be oxidized in the manufacturing steps to lose the metallic luster, thereby reducing the light reflectivity, but there is no related oxidation Description of the metallic luster of the time.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2007-017926

[Patent Document 2] Japanese Patent Laid-Open No. 2008-124450

[Patent Document 3] Japanese Patent Laid-Open No. 2009-185323

[Patent Document 4] Japanese Patent Laid-Open No. 2010-248619

[Patent Document 5] Japanese Patent Laid-Open No. 2010-258346

[Patent Document 6] Japanese Patent Laid-Open No. 2013-119632

[Non-patent literature]

[Non-Patent Document 1] Journal of the Japanese Metal Society, Vol. 72, No. 9, (2008), p. 703-707, Shinta Fujita, Kato Liangyu, Takayama Shinji

The problem to be solved by the present invention is to provide a sensor substrate having a low specific resistance and excellent adhesion to a sensor substrate such as a resin film or a glass substrate. The reflectivity of light and light is also low, and it is a good Cu alloy film for sensor electrodes or wiring of touch panels.

Another object of the present invention is to provide a material for a Cu alloy target and a Cu alloy target for manufacturing such a Cu alloy film.

Furthermore, another problem to be solved by the present invention is to provide a touch panel using such a Cu alloy film.

In order to solve the above problems, the gist of the Cu alloy target material of the present invention is intended to have the following configuration.

(1) The material for the above Cu alloy target

Contains Zn 0.1 ~ 10.0at%, further

Contains at least one element selected from the group consisting of Mg, Cr, Ca, Ti, Al, Sn, Ni, and B so that the total content becomes 0.1 to 6.0 at%, and the remainder contains Cu and inevitable impurities .

(2) The material for a Cu alloy target is used for a target for forming a Cu alloy film on a substrate, and the Cu alloy film is used for a sensor electrode and / or a wiring of a touch panel.

The Cu alloy target of the present invention is produced using the material for a Cu alloy target of the present invention.

The Cu alloy film of the present invention is formed on the substrate using the Cu alloy target of the present invention. Furthermore, the gist of the touch panel of the present invention is to include the Cu alloy film of the present invention.

If a Cu alloy film is formed using a Cu alloy target containing a predetermined amount of Zn and a predetermined amount (Mg, Cr, Ca, Ti, Al, Sn, Ni, B), and the Cu alloy film is subjected to the predetermined conditions Heat treatment can obtain relatively low specific resistance and resin substrate (especially PET Film substrate) or a Cu alloy film with excellent adhesion and low reflectivity.

The reason why the adhesion is improved is considered to be that a thickened layer containing more Zn, Mg, and the like is formed near the interface with the substrate by heat treatment. It is considered that the reason for suppressing the increase in specific resistance is that an intermetallic compound is formed in the Cu matrix in which Zn and Mg that are not consumed in forming the thickened layer are equal to the Cu matrix, and the amount of solid-solution elements in the Cu matrix decreases.

Furthermore, it is considered that the reason why the reflectance is lowered is that an oxide film containing Mg or the like is formed on the surface of the Cu alloy film by heat treatment.

Hereinafter, one embodiment of the present invention will be described in detail.

[1. Cu alloy target material and Cu alloy target]

The material for the Cu alloy target of the present invention and the Cu alloy target using the same include the following elements, and the remainder contains Cu and inevitable impurities. The types of added elements, their component ranges, and the reasons for their limitation are as follows.

[1.1. Components] (1) 0.1 ≦ Zn ≦ 10.0at%:

Zn does not significantly increase the specific resistance of the Cu alloy film, but has the effect of improving adhesion to a substrate (hereinafter sometimes referred to simply as a substrate) of a touch panel sensor such as a resin-based film or a glass substrate.

In order to obtain this effect, the Zn content needs to be 0.1at% or more. The Zn content is more preferably 0.6 at% or more, and even more preferably 2.0 at% or more.

On the other hand, if the Zn content is excessive, the specific resistance becomes excessively high. Therefore, the Zn content Must be 10.0at% or less. The Zn content is more preferably 6.0 at% or less, and still more preferably 5.0 at% or less. The Zn content is particularly preferably 2.0 ≦ Zn ≦ 6.0 at%.

(2) 0.1 ≦ Mg + Cr + Ca + Ti + Al + Sn + Ni + B ≦ 6.0at%:

Mg, Cr, Ca, Ti, Al, Sn, Ni, and B (hereinafter also collectively referred to as "adhesion improving elements M") all contribute to improving the adhesion of the Cu alloy film and reducing the reflectance. In order to obtain this effect, the total content of M needs to be 0.1at% or more. The total M content is more preferably more than 0.5 at%. The best is 1.0at% or more.

On the other hand, if the total content of M is excessive, the specific resistance becomes too high, and further, the hot workability decreases. Therefore, the total content of M must be 6.0at% or less. The total M content is more preferably 4.0 at% or less.

More preferably, 2.0 ≦ Zn ≦ 6.0at% and 1.0 ≦ M ≦ 6.0at%.

In addition, the Cu alloy target may contain any of these adhesion-improving elements M, and may contain two or more of them.

[1.2. Ingredient balance] (1) M / Zn ratio:

The adhesion improving element M has a function of forming a thickened layer containing more Zn and M near the interface with the substrate during the heat treatment. In addition, M and Zn which are not consumed in forming the thickened layer form a compound.

If the total content of M is excessive compared with the content of Zn, then M that has not been consumed in the formation of the thickened layer or the compound remains in the Cu matrix. When the residual amount of M becomes excessive, the specific resistance of the Cu matrix increases. In order to suppress the increase in specific resistance of the Cu alloy film, the ratio of the total content (at%) of the adhesion improving element M to the Zn content (at%) (= M / Zn ratio) is preferably 2.0 or more. under. The M / Zn ratio is more preferably 0.5 or less.

[1.3. Use]

The Cu alloy target material and the Cu alloy target of the present invention are used to form a Cu alloy film for a sensor electrode and / or a wiring of a touch panel. The Cu alloy film includes one formed on a substrate.

The Cu alloy film formed using the Cu alloy target of the present invention has high adhesion to a substrate (especially a PET film substrate). Therefore, it is not necessary to form a metal layer (adhesive layer) between the substrate and the Cu alloy film to improve the adhesion between them, and a Cu alloy film can be directly formed on the surface of the substrate.

[2. Cu alloy target material and manufacturing method of Cu alloy target]

In the present invention, the material for the Cu alloy target and the method for producing the Cu alloy target are not particularly limited.

For example, the target material can be produced by blending raw materials so as to have a predetermined composition, and melting and casting the blend. There are no particular restrictions on the method of melting and casting the formulation and its conditions, and various methods and conditions can be adopted according to the purpose.

When a target is produced from the target material thus obtained, the ingot is hot-worked and / or cold-worked. The processing method and conditions are not particularly limited, and various methods and conditions can be adopted according to the purpose.

[3. Cu alloy film]

The Cu alloy film of the present invention is formed on a substrate using the Cu alloy target of the present invention. The details of the method for forming the Cu alloy film will be described later.

[3.1. Thickening layer]

The Cu alloy film of the present invention preferably includes a thickened layer near the interface with the substrate. The so-called "thickened layer" refers to a layer formed near the interface with the substrate after the heat treatment described later, and refers to a region where the total content of Zn and the adhesion improving element M increases to 1.5 times or more before the heat treatment.

Even if a Cu alloy film containing only Zn is subjected to heat treatment, Zn hardly diffuses, and a thickened layer is not formed near the interface. On the other hand, when a Cu alloy film containing Zn and M is heat-treated, M diffuses to the vicinity of the interface. At the same time, Zn also diffused near the interface. As a result, a thickened layer containing more Zn and M was formed near the interface than before the heat treatment.

[3.2. Adhesiveness]

The thickened layer formed at the interface with the substrate contains a large amount of Zn with a large affinity for oxygen. Therefore, if the thickened layer is formed, the adhesion between the Cu alloy film and the substrate is improved.

If the content of the additive element and the heat treatment conditions are optimized, the adhesion to the substrate will be classified as 0 ~ 3 in the prescribed part of JIS K5600-5-6: 1999. When the manufacturing conditions are further optimized, the adhesion is classified into classifications 0 to 2 or classifications 0 to 1 according to the same specifications.

The contents of JIS K5600-5-6: 1999 are incorporated herein by reference.

[3.3. Specific resistance]

The effect of increasing the specific resistance of the Cu alloy film by Zn is small, but if it is excessively added, the specific resistance of the Cu alloy film is increased.

On the other hand, each of the adhesion improving elements M has a large effect of increasing the specific resistance of the Cu alloy film. However, if M and Zn are added at the same time, a thickened layer is formed during heat treatment, and at the same time, M and Zn are not consumed in the formation of the thickened layer to form a compound, so that the solid solution amount of these elements in the Cu matrix cut back. As a result, an increase in specific resistance of the Cu alloy film can be suppressed while maintaining high adhesion.

The sensor electrodes are required to have high responsiveness and low resistance heating loss even if the line width is 10 μm or less. For this reason, the specific resistance of the Cu alloy film as the sensor electrode is preferably 8.0 μΩ. cm or less.

Although the Cu alloy film of the present invention contains a relatively large amount of additional elements, the specific resistance is also small. If the manufacturing conditions are optimized, the specific resistance of the Cu alloy film after heat treatment becomes 6.0 μΩ. cm or below 5.0μΩ. cm or less.

[3.4. Reflectivity]

If the Cu alloy film is formed and heat-treated under an oxidizing ambient gas, a thickened layer is formed near the interface, and at the same time, an oxide film is formed on the surface of the Cu alloy film. Even if a Cu-Zn film is heat-treated under the conditions described later, it is difficult to form an oxide film, and metallic luster remains. If the metallic luster remains, the light from the outside is reflected by the Cu alloy film for the sensor electrode, making it difficult to see the screen.

In contrast, if a Cu alloy film containing Zn and M is heat-treated under an oxidizing ambient gas, an oxide film containing M is formed on the surface of the Cu alloy film, and the reflectance is reduced. When the manufacturing conditions are optimized, the reflectance of the Cu alloy film after the heat treatment becomes 50% or less, 30% or less, or 15% or less.

[3.5. Metal layers other than Cu alloy film]

In the present invention, the Cu alloy film needs to have a thickened layer to ensure adhesion to the substrate, and at the same time, to reduce the reflectance by oxidizing the surface of the counter electrode. On the other hand, if a metal layer other than the Cu alloy film is present on the counter electrode on the substrate side, the reduction in reflectance due to surface oxidation is hindered. Therefore, the metal layer other than the Cu alloy film is preferably 10 nm or less. The metal layer other than the Cu alloy film is more preferably 1 nm or less. The sensor electrode or wiring preferably contains only a Cu alloy film.

[3.6. Substrate]

The Cu alloy film of the present invention is formed on a substrate. The material of the substrate is not particularly limited, and various materials can be used.

Examples of the substrate material include polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polycarbonate (PC), and polymethyl Resin substrates such as methyl acrylate (PMMA) and poly (A).

The resin substrate is particularly preferably a polyethylene terephthalate (PET) film substrate. The reason is that it is particularly easy to handle. As the glass substrate, soda lime glass, TEMPAX glass, Pyrex (registered trademark) glass, quartz glass, or the like can be used.

[4. Manufacturing method of Cu alloy film]

The method for producing a Cu alloy film of the present invention includes a film forming step and a heat treatment step.

[4.1. Film formation step]

First, a Cu alloy film is formed on a substrate using the Cu alloy target of the present invention (film forming step).

In the present invention, the film forming method is not particularly limited, but it is preferably performed by a sputtering method. membrane. As the sputtering method, any sputtering method such as a direct current (DC) sputtering method, a radio frequency (RF) sputtering method, a magnetron sputtering method, or a reactive sputtering method can be used, as long as it is appropriately set The formation conditions are sufficient.

[4.2. Heat treatment step]

Next, the formed Cu alloy film is heat-treated under an oxidizing ambient gas (heat-treatment step). Thereby, a thickened layer is formed near the interface between the Cu alloy film and the substrate, and at the same time, an oxide film is formed on the surface of the Cu alloy film.

If the heat treatment temperature is too low, the formation of a thickened layer and the formation of an oxide film may change. Not enough. Therefore, the heat treatment temperature is preferably 50 ° C or higher. The heat treatment temperature is more preferably 70 ° C or higher, and even more preferably 100 ° C or higher. On the other hand, if the heat treatment temperature is too high, the substrate will melt. Therefore, the heat treatment temperature must not reach the melting point of the substrate.

The optimal heat treatment temperature varies depending on the material of the substrate. For example, in the case of a PET film substrate, the heat treatment temperature is preferably 320 ° C or lower. The heat treatment temperature is more preferably 250 ° C or lower, and even more preferably 200 ° C or lower.

The ambient gas during the heat treatment may be an oxidizing ambient gas capable of forming an oxide film that can reduce the degree of reflectance. The heat treatment is usually performed in the atmosphere.

The heat treatment time may be any time as long as a thickened layer can be formed to improve the adhesion and an oxide film can be formed to the extent that the reflectance can be reduced. Generally speaking, the higher the heat treatment temperature, the more the target thickened layer and the oxide film can be formed in a short time. The optimal heat treatment time varies depending on the composition or heat treatment temperature of the Cu alloy film, and is usually about 1 to 600 minutes.

Furthermore, when a Cu alloy film is used for a sensor electrode or a wiring of a touch panel, the Cu alloy film is usually uniformly formed on the surface of the substrate, and then it is etched and cleaned. Wash and dry. At this time, when the drying conditions are sufficient for forming the thickened layer and reducing the reflectance, a separate heat treatment step may be omitted.

[5. Touch Panel]

The touch panel of the present invention includes the Cu alloy film of the present invention. The Cu alloy film can be specifically used for a sensor electrode and / or a wiring of a touch panel. The sensor electrodes and / or wiring are formed on a substrate.

Other configurations of the touch panel are not particularly limited, and various configurations can be adopted according to the purpose.

[6. Role]

If a Cu alloy film is formed on a substrate using a Cu alloy target containing a predetermined amount of Zn, a Cu alloy film having a relatively low specific resistance and high adhesion to the substrate can be obtained. However, if only Zn is added to Cu, the improvement in adhesion to the substrate is limited.

On the other hand, if a Cu alloy film is formed using a Cu alloy target containing a predetermined amount of Zn and a predetermined amount (Mg, Cr, Ca, Ti, Al, Sn, Ni, B), and Cu is formed under predetermined conditions, By heat-treating the alloy film, a Cu alloy film having a relatively low specific resistance, excellent adhesion to a substrate, and low reflectance can be obtained.

The reason why the adhesion is improved is considered to be that a thickened layer containing more Zn, Mg, and the like is formed near the interface with the substrate by heat treatment. It is considered that the reason for suppressing the increase in specific resistance is that an intermetallic compound is formed in the Cu matrix in which Zn and Mg that are not consumed to form a thickened layer are equal to the Cu matrix, so that the amount of solid solution elements in the Cu matrix is reduced.

Furthermore, it is considered that the reason why the reflectance is lowered is that an oxide film containing Mg or the like is formed on the surface of the Cu alloy film by heat treatment.

[Example] (Examples 1 to 110, Comparative Examples 1 to 100) [1. Preparation of sample] [1.1. Production of Cu alloy target]

5 kg of the raw material prepared so as to have a predetermined composition was placed in a graphite crucible, and was melted by a high-frequency induction furnace. After melting, it was cooled in a furnace to obtain a crystal block. A Cu alloy target is produced by shaping this crystal ingot. A target of pure Al was also produced as a comparative material.

[1.2. Production of Cu alloy film]

The substrate is a 50mm × 50mm PET film and soda lime glass. Using an RF sputtering method or a DC sputtering method, a Cu alloy film is formed on the surface of a plurality of substrates. The film formation conditions were adjusted so that the film thickness became about 300 nm. After film formation, a heat treatment was performed at 150 ° C for 1.5 hours, except for the substrate for composition analysis.

[2. Test method] [2.1. Composition Analysis]

The composition was analyzed by using a substrate that has not been heat-treated, and analyzed by luminescence analysis of Inductively Coupled Plasma (ICP).

[2.2. Thickening layer]

For the Cu alloy film before and after the heat treatment, the thickness of the thickened layer is implemented by a secondary ion mass spectrometer (SIMS, Secondary Ion Mass Spectrometry) in the order from the surface of the Cu alloy film to the inside of the Cu alloy film, the Cu alloy film / each substrate. Determination of direction. The measured time-concentration profile was compared before and after the heat treatment to confirm the thickened layer.

[2.3. Specific resistance]

The four-probe method was used to measure the resistance of the Cu alloy film at five locations on the film, and the specific resistance (μΩ · cm) was calculated from the average value.

[2.4. Adhesiveness]

The adhesion of the Cu alloy film was evaluated in accordance with JIS K5600-5-6: 1999.

[2.5. Reflectivity]

A UV-visible spectrophotometer was used to measure a piece of heat-treated Cu alloy film. The ratio of the total reflected light beam to the parallel incident light beam of the test piece was set as the reflectance of light of this wavelength. The average value at 780 nm) is set as the reflectance of the material.

(Sum of reflectance in the wavelength range of visible light) / (wavelength range of visible light)

[3. Results]

The results are shown in Tables 1 to 6. Tables 1 to 3 show the results in the case of using a PET film as a substrate. Tables 4 to 6 show the results in the case of using soda-lime glass as the substrate. The following are known from Tables 1 to 6.

[3.1. Specific resistance]

The specific resistance of the Cu alloy was investigated. As a result, the specific resistance of the Zn-added alloy was low. In addition, when the amount of Zn is small or absent, the specific resistance increases due to the addition of Mg, Cr, Ca, B, Ti, Al, Sn, and Ni. On the other hand, the specific resistance of an alloy to which 4at% of Zn is added and further to which Mg, Cr, Ca, B, Ti, Al, Sn, and Ni are added is kept low. This is considered to be an effect caused by the formation of a compound with Zn.

Regarding Mn, the specific resistance increases regardless of the presence or absence of Zn. In addition, if a component added with Mg, Cr, Ca, B, Ti, Al, Sn, and Ni which is twice or more than Zn is added, the specific resistance is high. The reason is that even if a compound is formed with Zn, the remaining added elements are further dissolved in Cu.

[3.2. Adhesiveness]

Regarding adhesion, adhesion was high when Zn was added to any of Mg, Cr, Ca, B, Ti, Al, Sn, and Ni. In particular, alloys containing more than 0.1 at% of Zn and Mg, Cr, Ca, B, Ti, Al, Sn, and Ni have high adhesion. Furthermore, an alloy having 2 at% or more of Zn and Mg, Cr, Ca, B, Ti, Al, Sn, and Ni has excellent adhesion. When Zn, Mg, Cr, Ca, B, Ti, Al, Sn, Ni are added separately, the adhesion is low.

[3.3. Presence or absence of thickening layer]

In the case of an alloy containing only Zn, no thickened layer was observed after heat treatment at 150 ° C for 1.5 hours. On the other hand, if it is an alloy to which Mg, Cr, Ca, B, Ti, Al, Sn, Ni is added, a thickened layer is present.

[3.4. Reflectivity]

When the alloy is added with Mg, Cr, Ca, B, Ti, Al, Sn, and Ni, the reflectance is low and good.

[3.5. Relationship between added elements, characteristics and thickening layer]

Zn has excellent affinity for oxygen and improves adhesion to PET film or soda lime glass. However, the diffusion is slower at a low temperature of 150 ° C, so that a thickened layer is not formed between the PET film and the soda-lime glass, and the adhesion is improved to some extent.

On the other hand, if it is an alloy with Mg, Cr, Ca, B, Ti, Al, Sn, and Ni added, although a thickened layer is formed near the interface with the PET film or soda-lime glass, the adhesion is insufficient. And, the specific resistance increases. The reason is considered to be that these elements are dissolved in the Cu alloy to increase the specific resistance.

Regarding Mn, although it can improve the adhesion slightly, it does not form a thickened layer near the interface with the PET film or soda-lime glass, and the specific resistance also increases.

Therefore, at the same time, Mg, Cr, Ca, B, Ti, Al, Sn, Ni, and Zn that form a thickened layer with PET film or soda-lime glass even at low temperature are added at the same time. In the thick layer, not only Mg, Cr, Ca, B, Ti, and Al are thickened, but Zn is also thickened. The reason is that these elements have a characteristic of attracting each other with Zn. It can be understood that by these elements, Zn is also thickened at the same time.

On the other hand, regarding Mn, no thickened layer was observed even in the alloy to which Zn was added.

In this way, if Zn, Mg, Cr, Ca, B, Ti, Al, Sn, and Ni are added separately, the adhesion is slightly improved, and it cannot be used as a sensor electrode of a touch panel. If it is a certain distance Alloy systems with Mg, Cr, Ca, B, Ti, Al, Sn, Ni, and further Zn are excellent in adhesion to PET films and can achieve their goals.

[3.6. Relationship between the amount of added elements and characteristics]

On the other hand, as for the specific resistance, the specific resistance increase caused by Zn is small, but Mg, Cr, Ca, B, Ti, Al, Sn, and Ni increase the specific resistance significantly. Therefore, if the concentration of Zn is low and an alloy of Mg, Cr, Ca, B, Ti, Al, Sn, or Ni is added, the specific resistance increases significantly.

If the Zn concentration is high, a compound is formed between Zn and Zn. Therefore, even if Mg, Cr, Ca, B, Ti, Al, Sn, Ni are added, the solid solution of Cu in Mg, Cr, Ca, B, Ti, Al, Sn and Ni are also reduced to maintain low specific resistance.

The reflectance is considered to be drastically reduced by adding Mg, Cr, Ca, B, Ti, Al, Sn, and Ni bonded to oxygen during the heat treatment.

From the above, by adding Zn and Mg, Cr, Ca, B, Ti, Al, Sn, Ni as additive elements of Cu alloy, it can provide Cu with high adhesion, high electrical conductivity, and excellent light reflectance reduction. alloy.

The embodiments of the present invention have been described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention.

This application is based on Japanese Patent Application 2013-168392 filed on August 13, 2013, Japanese Patent Application 2014-009985 filed on January 23, 2014, and Japanese Patent Application 2014 filed on May 22, 2014 -106012, the content of which is incorporated into this application by reference.

(Industrial availability)

The Cu alloy target of the present invention can be used as a target for manufacturing a Cu alloy film, which is used for a sensor electrode of a touch panel, a wiring of a touch panel, and the like. In addition, the Cu alloy film of the present invention can be used for sensor electrodes of touch panels, wiring of touch panels, and the like.

Claims (11)

A material for a Cu alloy target having the following structure: (1) The material for a Cu alloy target includes Zn at 0.1 to 10.0 at%, and further includes a material selected from the group consisting of Mg, Cr, and At least one element in the group consisting of Ca, Al, Sn, Ni, and B, and the remainder contains Cu and inevitable impurities; and (2) the above-mentioned Cu alloy target material is used to form a Cu alloy on a substrate The target of the film, the Cu alloy film is used for the sensor electrode and / or wiring of the touch panel. For example, for the Cu alloy target material in the first patent application range, the content of Zn is 2.0 to 6.0 at%. For example, the material for a Cu alloy target according to item 1 or 2 of the patent application scope, wherein the total content of at least one element selected from the group consisting of Mg, Cr, Ca, Al, Sn, Ni, and B is relative to the above Zn content ratio: (Mg + Cr + Ca + Al + Sn + Ni + B) / Zn is 2.0 or less. A Cu alloy target is made by using a material for a Cu alloy target according to any one of claims 1 to 3. A Cu alloy film is formed on the substrate by using a Cu alloy target according to item 4 of the patent application. For example, the Cu alloy film according to item 5 of the patent application includes a thickened layer near the interface with the substrate. For example, the Cu alloy film of item 5 or 6 of the scope of patent application, wherein the adhesion to the above substrate is the classification 0 ~ 3 of the prescribed part in JIS K5600-5-6: 1999. For example, the Cu alloy film of the 5th or 6th in the scope of patent application, wherein the specific resistance is 8.0 μΩ. cm or less. For example, the Cu alloy film of item 5 or 6 of the patent application scope has a reflectance of 50% or less. For example, the Cu alloy film according to item 5 or 6 of the patent application scope, wherein the substrate is a polyethylene terephthalate (PET) film substrate. A touch panel includes a Cu alloy film according to any one of claims 5 to 10.