TWI818164B - Composite copper member, manufacturing method of composite copper member, laminated body, electronic component - Google Patents

Abstract

The purpose of the present invention is to provide a novel composite copper component. A composite copper member has a metal layer made of a metal other than copper formed on the fine unevenness made of copper and copper oxide on at least a part of the surface of the copper member. The surface of the composite copper member on which the metal layer is formed has fine unevenness. As for the unevenness, the average length (Rsm) of the roughness curve parameters of the surface of the composite copper component is 550nm or less, the surface area ratio is 1.3 or more and 2.2 or less, and the average thickness of the metal layer in the vertical direction is 15nm or more and 150nm or less.

Description

Composite copper member, manufacturing method of composite copper member, laminated body, electronics Component

The present invention relates to composite copper components.

Copper foil used for printed wiring boards requires good adhesion to resin. In order to improve this adhesion, the surface of the copper foil has been roughened by etching, which is a method of improving mechanical adhesion through the so-called anchor effect. However, from the viewpoint of high density of printed wiring boards or transmission loss in high frequency bands, the copper foil surface also needs to be planarized. In order to satisfy the above-mentioned opposite requirements, a copper surface treatment method that performs an oxidation step, a reduction step, etc. has been developed (see Patent Document 1). According to this method, the copper foil is pre-treated and immersed in a solution containing an oxidizing agent to oxidize the surface of the copper foil to form unevenness of copper oxide, and then immersed in a solution containing a reducing agent to reduce the copper oxide, thereby adjusting the surface texture. Bump. In addition, a method of adding interface active molecules in the oxidation step has been developed as a method for improving the adhesion of copper foil treatment by oxidation and/or reduction (see Patent Document 2), and the use of aminothiazole-based compounds after the reduction step, etc. A method of forming a protective film on the surface of copper foil (see Patent Document 3). In this way, the distance between the convex portions of the uneven copper oxide is shorter than the wavelength range of visible light (for example, 750 nm to 380 nm), and the visible light incident on the roughened layer is diffused within the fine uneven structure, resulting in attenuation. Therefore, the roughened layer functions as a light-absorbing layer that absorbs light, and the surface of the roughened surface becomes darker in color such as blackening or browning than before the roughening treatment. Therefore, the color tone of the roughened surface of the copper foil is also distinctive, and it is known that the lightness L ^* value of the L ^* a ^* b ^* color system is 25 or less (Patent Document 4).

On the other hand, there is also a method of plating the unevenness on the roughened surface of the copper foil to improve the mechanical adhesion. However, the plating film is only used to prevent the unevenness from becoming smooth and fine due to leveling. The uneven shape is filled up, so it has dispersed metal particles (Patent Document 5).

Patent document 1 is International Publication No. WO2014/126193; Patent document 2 is Japanese Patent Application Publication No. 2013-534054; Patent document 3 is Japanese Patent Application Publication No. 8-97559; Patent document 4 is Japanese Patent Application Publication No. 2017-48467 ; Patent Document 5 is Japanese Patent Application Laid-Open No. 2000-151096.

The purpose of the present invention is to provide a novel composite copper component.

As a result of intensive research, the present inventors have successfully produced a novel composite copper component, which has a uniform thickness and non-dispersed metal layer on the fine unevenness formed by copper and copper oxide, and suppresses the smoothing effect on the surface. The present invention has the following implementation aspects:

[1] A composite copper member in which a metal layer made of a metal other than copper is formed on the fine unevenness made of copper and copper oxide on at least a part of the surface of the copper member, and the metal layer is formed on the composite copper member. The surface of the component has fine unevenness. The average length (Rsm) of the thickness curve parameter of the surface of the composite copper component is 550nm or less, the surface area ratio is 1.3 or more and 2.2 or less, and the average thickness of the metal layer in the vertical direction is 15nm or more. And below 150nm.

[2] The composite copper member according to [1], wherein the lightness L ^* value of the surface of the composite copper member is less than 35.

[3] The composite copper component of [1] or [2], wherein the metal layer is selected from the group consisting of tin, silver, zinc, aluminum, titanium, bismuth, chromium, iron, cobalt, nickel, palladium, gold and platinum. At least one metal in the group.

[4] The composite copper member according to any one of [1] to [3], wherein the composite copper member Among the fine unevenness on the surface, Rz is 0.25 μm or more and 1.2 μm or less.

[5] A method of manufacturing a composite copper member, which is a method of manufacturing the composite copper member described in [1], including a first step and a second step. The first step is to form fine unevenness on the surface of the copper member through oxidation treatment. part, the second step is to perform a plating process using a metal other than copper on the fine uneven parts on the surface of the copper component, so that the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less, and the metal layer is formed The surface of the composite copper member of the layer has fine unevenness, the average length Rsm of the roughness curve parameter of the surface of the composite copper member is 550 nm or less, and the surface area ratio is 1.3 or more and 2.2 or less.

[6] The manufacturing method of the composite copper component according to [5], in the second step, the plating treatment is electroplating treatment.

[7] A laminated body produced using the composite copper member according to any one of [1] to [4].

[8] An electronic component made of the composite copper component according to any one of [1] to [4].

[Figure 1] A graph showing the relationship between the average length of the thickness curve parameter (Rsm) and the peel strength (normal) in Examples and Comparative Examples.

[Figure 2] A graph showing the relationship between surface area ratio and peel strength (normal) in Examples and Comparative Examples.

[Figure 3] In Examples and Comparative Examples, L ^* a ^* b ^* represents the relationship between the lightness L ^* of the color system and the peel strength (normal).

[Figure 4] The relationship between the average thickness of the plating layer in the vertical direction (plating thickness) and ΔE*ab in Examples and Comparative Examples.

[Figure 5] Average thickness of the plating layer in the vertical direction (plating thickness) in Examples and Comparative Examples Relationship diagram with peel strength (normal).

[Figure 6] Results of measurement of transmission loss in Example 2 and Comparative Example 1.

Preferred embodiments of the present invention will be described in detail below using additional drawings, but are not limited thereto. Furthermore, from the description of this specification, a person with ordinary knowledge in the technical field to which the invention belongs will understand the purpose, characteristics, advantages and concepts of the present invention, and a person with ordinary knowledge in the technical field to which the invention belongs can easily reproduce it based on the description of this specification. invention. The embodiments and specific examples of the invention described below represent preferred embodiments of the invention and are used for illustration and explanation and are not intended to limit the invention. It will be apparent to those with ordinary skill in the technical field to which the invention belongs that various modifications can be made based on the description of this specification within the intention and scope of the invention disclosed in this specification.

Composite copper member: One embodiment of the present invention is a composite copper member, in which a metal layer composed of a metal other than copper is formed on the fine unevenness formed of copper and copper oxide on at least part of the surface of the copper member. The copper member is a part of the structure and is a material containing copper as a main component, including, but not limited to, copper foil such as electrolytic copper foil, rolled copper foil, and carrier-attached copper foil, copper wire, copper plate, copper lead frame, and the like.

When the copper member is copper foil, the thickness of the copper foil is not particularly limited, but is preferably 0.1 μm or more and 100 μm or less, more preferably 0.5 μm or more and 50 μm or less.

In the composite copper member according to one embodiment of the present invention, the average length (RSm) of the roughness curve parameter of the surface formed with the metal layer made of metal other than copper is 550 nm or less, preferably 450 nm or less, and more preferably 350 nm. the following. Here, RSm represents the average length of one cycle of unevenness (i.e., the length of the profile curve parameter:

Here, 10% of the arithmetic mean roughness (Ra) is used as the minimum height of the unevenness, and 1% of the reference length (lr) is used as the minimum length to define one periodic amount of unevenness. For example, Rsm can be measured and calculated based on "Measurement of Surface Roughness of Precision Ceramic Thin Films Using Atomic Force Microscope (JIS R 1683:2007)".

The surface area ratio of the composite copper member according to one embodiment of the present invention is 1.3 or more, preferably 1.4 or more, more preferably 1.5 or more, and 2.2 or less, preferably 2.1 or less, and more preferably 2.0 or less. Here, the surface area ratio is the ratio of the surface area to the area within a predetermined range. For example, if the surface area ratio is 1, it is a completely flat state with no surface roughness. The larger the surface area ratio, the more severe the unevenness of the surface. In addition, the area of a prescribed range corresponds to the surface area of the range if the surface of the range is flat. The surface area ratio can be calculated, for example, by the following method. The surface of the composite copper member on which the metal layer made of metal other than copper is formed is observed with an atomic force microscope (AFM), and an AFM shape image is obtained. This observation was repeated for 10 randomly selected locations, and the surface areas S1, S2,..., S10 were calculated using AFM. Then, the average surface area of the surface of the composite copper member can be obtained by simply taking the arithmetic average of the ratio (surface area/area) SR1, SR2, ..., SR10 of the surface areas S1, S2, ..., S10 and the area of their respective observation areas. Rate.

In the composite copper member according to one embodiment of the present invention, the lightness L ^* of the surface on which the metal layer made of metal other than copper is formed is 35 or less (or less), preferably 30 or less (or less). It is better to be below 25 (or less). Here, the lightness L ^* is an index for measuring surface roughness in the L ^* a ^* b ^* colorimetric system, and can be calculated by measuring the amount of light reflection when the surface of the measurement sample is irradiated with light. For example, L ^* =0 represents black, and L ^* =100 represents white diffuse color. The specific calculation method can be based on JIS Z8105 (1982). When measuring the brightness of the surface of a composite copper component with a metal layer formed on it, when the gaps (i.e. Rsm) in the uneven parts of the surface are narrow, the amount of light reflection is reduced, so the brightness value tends to decrease; when the gaps in the uneven parts are wide, The amount of light reflected increases, so the brightness value tends to increase.

One embodiment of the present invention is a composite copper member. The Rz of the surface on which the metal layer made of metal other than copper is formed is 1.00 μm or less, preferably 0.90 μm or less, more preferably 0.80 μm or less, and 0.10 μm. Above, preferably 0.15 μm or more, more preferably 0.20 μm or more. Here, the maximum height roughness (Rz) represents the sum of the maximum value of the peak height Zp and the maximum value of the valley depth Zv of the contour curve (y=Z(x)) in the reference length l. Surface roughness Rz can be calculated according to the method specified in JIS B 0601:2001 (based on international standard ISO13565-1).

The type of metal contained in the metal layer is not particularly limited as long as it is other than copper. It is preferably selected from the group consisting of tin, silver, zinc, aluminum, titanium, bismuth, chromium, iron, cobalt, nickel, palladium, gold and platinum. At least one metal in the group. In particular, in order to make it have acid resistance and heat resistance, it is preferable to use a metal with higher acid resistance and heat resistance than copper, such as nickel, palladium, gold, platinum or alloys thereof.

In the composite copper member, the average thickness of the metal other than copper contained in the metal layer in the vertical direction is not particularly limited, but is preferably 15 nm or more, more preferably 20 nm or more, and still more preferably 25 nm or more. However, if it is too thick, the fine unevenness on the surface of the composite copper member will be smoothed by the leveling effect, and the peel strength will also decrease. Therefore, the thickness is preferably 150 nm or less, more preferably 100 nm or less or 75 nm or less. In addition, the average thickness in the vertical direction of metals other than copper contained in the metal layer can be calculated by dissolving the metal layer in an acidic solution, measuring the amount of metal by ICP analysis, and dividing by the area of the composite copper member. Alternatively, it can also be calculated by dissolving the composite copper member itself and detecting and measuring only the amount of metal forming the metal layer.

A metal layer made of metal other than copper can be formed on the surface of the copper component by plating. The plating method is not particularly limited, and plating can be performed by electroplating, electroless plating, vacuum evaporation, chemical conversion treatment, etc. Electroplating is preferred because a uniform and thin plating layer is preferably formed. From now on, the coating process including vacuum evaporation and chemical conversion treatment is called plating. When electroplating is performed on the surface of an oxidized copper component, the copper oxide (CuO) on the surface is first reduced, and an electric charge is required to form cuprous oxide (Cu ₂ O) or pure copper, so there is a time lag until plating is formed. . For example, when nickel plating is applied to a copper member, in order to keep the thickness within the above-mentioned preferred range, it is preferable to apply a charge of 15C/dm ² or more to 75C/dm ² or less per unit area of the copper member to be electroplated. , it is better to apply a charge of more than 25C/dm ² to less than 65C/dm ² .

Manufacturing method of composite copper components: One embodiment of the present invention is a manufacturing method of composite copper components, including a first step and a second step. The first step is to form fine unevenness on the surface of the copper component through oxidation treatment. The second step is to form fine unevenness on the surface of the copper component through oxidation treatment. The second step is to perform plating treatment on the surface of the copper component with fine unevenness.

First, in the first step, the surface of the copper component is oxidized with an oxidizing agent to form a layer of copper oxide, and fine unevenness is formed on the surface. Copper oxide includes copper oxide and cuprous oxide. This oxidation step does not need to be preceded by a roughening step such as etching, but may be performed. In addition, degreasing cleaning can be performed before the oxidation treatment, acid cleaning can be performed to make the surface uniform by removing the natural oxide film, or alkali treatment can be performed after the acid cleaning to prevent the acid from being brought into the oxidation step. The method of alkali treatment is not particularly limited. It is better to use an alkaline aqueous solution of 0.1~10g/L, and more preferably an alkaline aqueous solution of 1~2g/L. The alkaline aqueous solution, such as sodium hydroxide aqueous solution, is treated at 30~50°C for 0.5 ~2 minutes is enough.

The oxidizing agent is not particularly limited, and for example, aqueous solutions such as sodium chlorite, sodium hypochlorite, potassium chlorate, potassium perchlorate, and potassium persulfate can be used. Various additives (for example, phosphates such as trisodium phosphate dodecahydrate) or surface-active molecules can be added to the oxidizing agent. Examples of surface-active molecules include rhodopsin, rhodopsin macrocycle, expanded rhodopsin, cyclic rhodopsin, linear rhodopsin polymers, rhodopsin sandwich coordination complexes, rhodopsin arrays, silane, and tetraorgano-silane. , Aminoethyl-aminopropyl-trimethoxysilane, (3-aminopropyl)trimethoxysilane, (1-[3-(trimethoxysilyl)propyl]urea) (1- [3-(Trimethoxysilyl)propyl]urea), (3-aminopropyl)triethoxysilane, (3-epoxypropyloxypropyl)trimethoxysilane, (3-chloropropyl)trimethoxysilane Silane, (3-epoxypropyloxypropyl)trimethoxysilane, dimethyldichlorosilane, 3-(trimethoxysilyl)propylmethacrylate, ethyltriethyloxysilane , triethoxy (isobutyl)silane, triethoxy (octyl)silane, 2-methoxyethoxy (vinyl)silane, chlorotrimethylsilane, methyltrichlorosilane, tetrachloride Silicon, tetraethoxysilane, phenyltrimethoxysilane, chlorotriethoxysilane, vinyl-trimethoxysilane, amine, sugar, etc.

The oxidation reaction conditions are not particularly limited. The liquid temperature of the oxidation chemical liquid is preferably 40 to 95°C, and more preferably 45 to 80°C. The reaction time is preferably 0.5 to 30 minutes, more preferably 1 to 10 minutes.

In the first step, a dissolving agent can be used to dissolve the surface of the oxidized copper component to adjust the unevenness of the surface of the copper component.

The dissolving agent used in this step is not particularly limited, but is preferably a chelating agent, especially a biodegradable chelating agent. Examples include ethylenediaminetetraacetic acid, dihydroxyethylglycine, and L-glutamic acid diacetic acid. Tetrasodium, ethylenediamine-N,N'-disuccinic acid, sodium 3-hydroxy-2,2'-iminodisuccinate, trisodium methylglycine diacetate, tetrasodium aspartic acid diacetate Sodium, disodium N-(2-hydroxyethyl)iminodiacetate, sodium gluconate, etc.

The pH value of the dissolving medicinal solution is not particularly limited, but it is preferably alkaline, more preferably pH 8.0 to 10.5, further preferably pH 9.0 to 10.5, further preferably pH 9.8 to 10.2.

Moreover, in the first step, a chemical solution containing a reducing agent (reducing chemical solution) can be used to reduce the copper oxide formed by the oxidized copper component to adjust the number or length of the concavities and convexities.

As the reducing agent, DMAB (dimethylamine borane), diborane, sodium borohydride, hydrazine, etc. can be used. Moreover, the chemical liquid for reduction is a liquid containing a reducing agent, an alkaline compound (sodium hydroxide, potassium hydroxide, etc.), and a solvent (pure water, etc.).

Next, in the second step, the surface of the copper member on which the fine protrusions are formed is plated with a metal other than copper to produce a composite copper member. Conventional techniques may be used for the plating treatment. For example, for metals other than copper, tin, silver, zinc, aluminum, titanium, bismuth, chromium, iron, cobalt, nickel, palladium, gold, platinum or various alloys may be used. The plating step is not particularly limited, and plating can be performed by electroplating, electroless plating, vacuum evaporation, chemical conversion treatment, or the like. In one embodiment of the present invention, it is preferred to form a uniformly thin plating layer, so plating is preferably electroplating. In the past, copper plating was used to form ridge-like irregularities on the copper surface of copper components, and the plating process was further layered to provide heat resistance and chemical resistance. However, in the present invention, copper oxides formed by oxidation treatment are used. And the surface of the copper component with uniform and fine unevenness is plated.

In the case of electroplating, nickel plating, nickel alloy plating, etc. are preferred. Examples of nickel plating and nickel alloy plating include pure nickel, nickel-copper alloy, nickel-chromium alloy, nickel-cobalt alloy, nickel-zinc alloy, nickel-manganese alloy, nickel-lead alloy, nickel-phosphorus alloy, and the like. Examples of the supplying agent for plating ions include nickel sulfate, nickel sulfamate, nickel chloride, nickel bromide, zinc oxide, zinc chloride, palladium diamine dichloride, ferric sulfate, ferric chloride, anhydrous chromic acid, Chromium chloride, sodium chromium sulfate, copper sulfate, copper pyrophosphate, cobalt sulfate, manganese sulfate, sodium hypophosphite, etc. Other additives including pH buffers or gloss agents may be used, such as boric acid, nickel acetate, citric acid, sodium citrate, ammonium citrate, potassium formate, malic acid, sodium malate, sodium hydroxide, potassium hydroxide, and sodium carbonate. , ammonium chloride, sodium cyanide, potassium sodium tartrate, potassium thiocyanate, sulfuric acid, hydrochloric acid, potassium chloride, ammonium sulfate, ammonium chloride, potassium sulfate, sodium sulfate, sodium thiocyanate, sodium thiosulfate, potassium bromate , potassium pyrophosphate, ethylenediamine, nickel ammonium sulfate, sodium thiosulfate, fluorosilicic acid, sodium fluorosilicate, strontium sulfate, cresolsulfonic acid, β-naphthol, saccharin, 1,3,6-naphthalene trisulfate Sulfonic acid, sodium naphthalene disulfonate, sodium naphthalene trisulfonate, sulfonamide, sulfinic acid, 1,4-butynediol, coumarin, sodium lauryl sulfate, etc. The preferred bath composition for nickel plating can include, for example, nickel sulfate (above 100g/L~350g/L), nickel sulfamate (above 100g/L~600g/L), nickel chloride (above 0g/L~ 300g/L or less) and mixtures thereof may also contain sodium citrate (0g/L or more to 100g/L or less) or boric acid (0g/L or more to 60g/L or less) as additives.

In the case of electroless nickel plating, it is better to use a catalyst for processing. Catalysts can use iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and their salts. By using a catalyst for treatment, a uniform metal layer without particles dispersed everywhere can be obtained. This improves the heat resistance of the composite copper foil. The reducing agent used in the case of electroless nickel plating is preferably a reducing agent that does not have catalytic activity of copper and copper oxide. Examples of reducing agents that do not have catalytic activity in copper and copper oxide include hypophosphorous acid such as sodium hypophosphite. salt.

In this way, by performing the first step and the second step on the copper member, a composite copper member can be produced. A metal layer made of a metal other than copper is formed on at least a part of the surface of the copper member, and a metal layer made of a metal other than copper is formed. The surface of the composite copper component of the metal layer composed of metal has fine unevenness, Rsm is 550nm or less, the surface area ratio is 1.3 or more and 2.2 or less, and the average thickness of the metal layer in the vertical direction is 15nm or more and 150nm or less.

Without impairing the technical characteristics of the present invention, the composite copper component manufactured through these steps can be coupled with a silane coupling agent or the like or rust-proofed with benzotriazole.

Utilization method of composite copper component: The composite copper component of the present invention can be used for electronic components such as copper foil used for printed wiring boards, copper wires for wiring on substrates, and copper foil used for LIB negative electrode current collectors. For example, the composite copper foil of the present invention and resin are bonded into a layered form to prepare a laminate for use in manufacturing printed wiring boards. The type of resin in this case is not particularly limited, but is preferably polyphenylene ether, epoxy resin, PPO, PBO, PTFE, LCP or TPPI. Furthermore, by using the composite copper foil of the present invention as a LIB negative electrode current collector, the adhesion between the copper foil and the negative electrode material can be improved, and a good lithium ion battery with less capacity degradation can be obtained. The negative electrode current collector used in lithium ion batteries can be manufactured according to conventional methods. For example, a negative electrode material containing a carbon-based active material is prepared and dispersed in a solvent or water to form an active material slurry. After the active material slurry is coated on the composite copper foil of the present invention, the solvent or water is evaporated and dried. After that, it is pressed and dried again to form the negative electrode current collector into the desired shape. In addition, the negative electrode material may also include silicon or silicon compounds, germanium, tin or lead, etc., which have a larger theoretical capacity than the carbon-based active material. In addition, as the electrolyte, in addition to an organic electrolyte solution in which a lithium salt is dissolved in an organic solvent, a polymer made of polyethylene glycol, polyvinylidene fluoride, or the like can also be used. In addition to being used in lithium-ion batteries, the composite copper foil of the present invention can also be used in lithium-ion polymer batteries.

(Examples) <1. Production of composite copper foil>: Comparative Examples 2 to 8 and Examples 1 to 5 The bright side (glossy side, flat side when compared with the opposite side) of DR-WS (furukawa Electric Co., Ltd., thickness 18 μm) copper foil was used. Example 6 also uses DR-WS but uses a matte surface (matte surface, which is a rougher surface when compared with the opposite surface). Comparative Example 1 used the matte surface of FV-WS (manufactured by Furukawa Electric Co., Ltd., thickness 18 μm). In addition, the copper foil of Comparative Example 1 was not subjected to surface treatment such as oxidation treatment of the present invention.

(1) Pretreatment: [Alkali degreasing treatment] Immerse the copper foil in a sodium hydroxide aqueous solution with a liquid temperature of 50°C and 40g/L for 1 minute, and then wash with water.

[Pickling treatment] The copper foil that has been subjected to alkali degreasing treatment is immersed in a 10% by weight sulfuric acid aqueous solution with a liquid temperature of 25°C for 2 minutes, and then washed with water.

[Pre-soaking treatment] Immerse the pickled copper foil in a pre-soaking solution with a liquid temperature of 40°C and sodium hydroxide (NaOH) 1.2g/L for 1 minute.

(2) Oxidation treatment: For the alkali-treated copper foil, Examples 1 to 6 and Comparative Examples 4 to 7 were treated with an oxidation treatment aqueous solution (NaClO ₂ 60g/L; NaOH 9g/L; 3-epoxypropyl oxide Propyltrimethoxysilane 2g/L) was oxidized at 73°C for 2 minutes. In Comparative Example 8, an oxidation treatment was performed with an aqueous oxidation treatment solution (NaClO ₂ 37.5 g/L; NaOH 100 g/L) at 73° C. for 4 minutes. After these treatments, the copper foil is washed with water.

Comparative Example 4 was immersed in a reducing agent (dimethylamine borane 5 g/L; sodium hydroxide 5 g/L) at room temperature for 1 minute after the oxidation treatment, and the reduction treatment was performed.

(3) Plating treatment: In Examples 1 to 6 and Comparative Examples 6 to 8, the oxidized copper foil was treated with the electrolyte for nickel plating (nickel sulfate 240g/L; nickel chloride 45g/L; citric acid Trisodium 20g/L) is electroplated (current density per unit area of copper foil 0.5A/dm ² ). In Comparative Examples 2 and 3, no oxidation treatment was performed, and electroplating was performed using the same nickel plating electrolyte solution. The processing times are respectively 50 seconds (Example 1), 60 seconds (Example 2), 70 seconds (Example 3), 100 seconds (Example 4), 120 seconds (Example 5), and 130 seconds (Example 6). ), 10 seconds (Comparative Example 2), 35 seconds (Comparative Example 3), 40 seconds (Comparative Example 6), 150 seconds (Comparative Example 7), and 220 seconds (Comparative Example 8).

(4) Coupling treatment: For Examples 1 to 6 and Comparative Examples 2 to 8, the copper foil was treated with 3-aminopropyltriethoxysilane (1% by weight) at room temperature for 1 minute, and then fired at 110°C. 1 minute.

For Examples and Comparative Examples, several test pieces were produced under the same conditions. In Comparative Examples 2 to 8 and Examples 1 to 5, the shiny surface with surface treatment was used as the evaluation surface. In Example 6, the matte surface with surface treatment was used as the evaluation surface. In Comparative Example 1, the matte surface was used as the evaluation surface.

<2. Calculation of Rz>: The test pieces of the examples and comparative examples were observed using a conjugate focal scanning electron microscope OPTELICS H1200 (manufactured by Lasertec Co., Ltd.), and a profile curve was created from the observation results in accordance with JIS B 0601:2001. Method to calculate Rz. Measurement conditions: scanning width is 100 μm, scanning type is Area, light source is blue light, and Cut-off value is 1/5. Connect the objective lens x100, the eyepiece x14, the digital zoom x1, and set the Z pitch to 10nm. Obtain the data at 3 positions, and the average of the 3 positions is taken as Rz.

<3.Measurement of RSm and surface area ratio>: The RSm and surface area ratio of the test pieces of the examples and comparative examples were calculated based on JIS R 1683:2007 by observing with an atomic force microscope (AFM: Atomic Force Microscope). Only in Comparative Example 1, Ra=150nm was calculated.

Device: Made by Hitachi High-Tech Science

probe station AFM5000II

Connected model: AFM5300E

Cantilever: SI-DF40

Use the automatic setting function of AFM5000II to set

(Amplitude attenuation rate, scanning frequency, I gain, P gain, A gain, S gain)

Scanning area: 5μm square

Number of pixels: 512x512

Measurement mode: DFM

Measurement field of view: 5μm

SIS mode: not used

Scanner: 20μm scanner

Measurement method: Measure with 3 corrections.

◆RSm: Average cross-section analysis (lr=5μm)

◆Surface area ratio: Surface roughness analysis

<4. Measurement of lightness L ^* >: L ^* a ^* b ^* Color system lightness L ^* was measured using a spectrophotometer NF999 manufactured by Nippon Denshoku Industries Co., Ltd. (illumination condition: C; viewing angle condition: 2; measurement Project: L ^* a ^* b ^* ) to carry out.

<5. Plating thickness measurement and surface element analysis> The average thickness of plating in the vertical direction is measured by dissolving the copper component in 12% nitric acid, and using the resulting liquid with an ICP emission spectrometer 5100 SVDV ICP-OES (Agilent Technologies Co., Ltd.) analyzes and measures the metal concentration, and calculates the thickness of the layered metal layer by considering the metal density and the surface area of the metal layer. For surface element analysis, QuanteraSPM (manufactured by ULVAC-PHI) was used to perform narrow spectrum analysis (narrow) on the outermost surface using the following steps to confirm whether copper and metals other than copper can be detected on the surface where the metal layer is formed.

(1)Survey Spectrum

First detect the element using the following conditions.

X-ray beam diameter: 100μm (25w15kV)

Pass energy: 280eV, 1eV step

Line analysis: φ 100μm*700μm

Cumulative times: 6 times

(2)Narrow Spectrum

For the elements detected in (1), the following conditions are used to obtain a narrow spectrum. Among the detected components, nitrogen and carbon When the total amount of other elements is taken as 100%, the ratio of each detected component is calculated as a quantitative value.

X-ray beam diameter: 100μm (25w15kV)

Pass energy: 112eV, 0.1eV step

Line analysis: φ 100μm*700μm

<6. Measurement of heat resistance of copper foil> The heat resistance of the test pieces of the examples and comparative examples was tested by color change caused by heating. After measuring the color difference (L*, a*, b*) of the test piece before heat treatment, place it in an oven at 225°C for 30 minutes, and measure the color difference of the test piece after heat treatment. From the obtained value, ΔE*ab is calculated according to the following formula.

△E ^* ab=[(△L ^* ) ² +(△a ^* ) ² +(△b ^* ) ² ] ^1/2

<7. Measurement of Peel Strength (Normal, After Acid Resistance Test)> In addition, the peel strength of the test pieces of Examples and Comparative Examples was measured before and after acid treatment. Specifically, first, each copper foil laminated prepreg R5670KJ (manufactured by Panasonic, thickness 100 μm) was heated and pressed using a vacuum high-pressure press under the conditions of a pressurizing pressure of 2.9 MPa, a temperature of 210° C., and a pressing time of 120 minutes. , thereby obtaining a laminated body. For Examples and Comparative Examples, several laminated bodies were produced under the same conditions. In order to know its resistance to acid, one laminated body was kept as it was (normal), and the other laminated body was immersed in an acid solution (after the acid resistance test) and was used as a measurement sample. Moreover, the acid liquid immersion was performed by immersing the laminated body in 4N hydrochloric acid at 60 degreeC for 90 minutes. The 90° peel test (Japanese Industrial Standard (JIS) C5016) was performed on these measurement samples, and the peel strength (kgf/cm) was measured.

<8. Measurement of High Frequency Characteristics> For the test pieces of Example 2 and Comparative Example 1, the resin base material prepreg R5670KJ (manufactured by Panasonic Corporation) was laminated by hot press molding, and then a sample for measuring transmission characteristics was produced and measured. Transmission loss in high frequency bands. The evaluation of transmission characteristics is measured using the conventional stripline resonator method suitable for measurement in the 0~40GHz frequency band. Specifically, the S21 parameter was measured without a coverlay film under the following conditions. Measurement conditions: microstrip line structure; base material prepreg R5670KJ; circuit length: 100mm; conductor width 250μm; conductor thickness 28μm; The substrate thickness is 100μm; the characteristic impedance is 50Ω.

<9. Results> The results are shown in Table 1 and Figures 1 to 6.

Table 1

Comparative Example 1 has a large RSm, no fine unevenness and an elevated L ^* . Since RSm is large and the surface area ratio is high, the increase in surface area is considered not to be an increase in density in the plane direction, but in the height direction. In fact, Rz is larger. As shown in Figure 6, the influence of the skin effect leads to actual The high-frequency characteristics deteriorate. Since the RSm of Comparative Examples 2 and 3 was large and the surface area ratio was small, it was considered that adhesion was not obtained. Comparative Example 4 has no plating, so the heat-resistant discoloration (ΔE ^* ab) is large. Comparative Example 5 has no plating and only oxidation treatment. Therefore, copper oxide is the main component in the fine unevenness, so the peel strength in the acid resistance test is reduced. The plating thickness of Comparative Example 6 was insufficient, so the heat discoloration resistance value was large. The plating thickness of Comparative Example 7 was too thick and caused a leveling effect, so RSm increased and the surface area ratio became small, resulting in a decrease in peel strength. The surface area ratio of Comparative Example 8 was too large, so the plating was uneven and heat-resistant discoloration occurred. In comparison, the average length (Rsm) of the surface roughness curve parameter is 550nm or less (Figure 1), the surface area ratio is 1.3 or more and 2.2 or less (Figure 2), and the average thickness of the metal layer in the vertical direction is 15nm. The composite copper foils of Examples 1 to 6, which are above and below 150nm (Figure 5) and have a brightness L ^* value of less than 35 (Figure 3), have high peel strength and small heat-resistant discoloration (△E ^* ab). Even after passing The peel strength does not decrease after the acid resistance test. In addition, the high frequency characteristics of Example 2 are also good.

Industrial Applicability: According to the present invention, novel composite copper members, laminates using the same, and electronic components can be provided.

Claims (8)

A composite copper member in which a metal layer made of a metal other than copper is formed on the fine unevenness made of copper and copper oxide on at least a part of the surface of the copper member, and the surface of the composite copper member on which the metal layer is formed It has fine unevenness, the average length (Rsm) of the thickness curve parameter of the surface of the composite copper component is 550nm or less, the surface area ratio is 1.3 or more and 2.2 or less, and the average thickness of the metal layer in the vertical direction is 15nm or more and 150nm or less. . The composite copper component of claim 1, wherein the brightness L ^* value of the surface of the composite copper component is less than 35. The composite copper component of claim 1 or 2, wherein the metal layer includes at least one selected from the group consisting of tin, silver, zinc, aluminum, titanium, bismuth, chromium, iron, cobalt, nickel, palladium, gold and platinum. A kind of metal. The composite copper member according to claim 1 or 2, wherein Rz is 0.25 μm or more and 1.2 μm or less among the fine unevenness on the surface of the composite copper member. A method of manufacturing a composite copper component, which is a method of manufacturing the composite copper component of claim 1, including a first step and a second step. The first step is to form fine uneven portions on the surface of the copper component through oxidation treatment. The third step The second step is to perform a plating process using a metal other than copper on the fine uneven portions on the surface of the copper component so that the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less, forming the composite with the metal layer. The surface of the copper member has fine unevenness, the average length Rsm of the roughness curve parameter of the surface of the composite copper member is 550 nm or less, and the surface area ratio is 1.3 or more and 2.2 or less. For the manufacturing method of a composite copper component according to claim 5, in the second step, the plating treatment is an electroplating treatment. A laminated body produced using the composite copper member according to any one of claims 1 to 4. An electronic component made of the composite copper component according to any one of claims 1 to 4.