JP2020186464A - Composite copper member - Google Patents

Abstract

To provide a new composite copper member.MEANS FOR SOLVING THE PROBLEM: A composite copper member includes a metal layer consisting of metal except copper on fine irregularities including copper and copper oxide on the surface of at least a part of a copper member. The surface of the composite copper member having the metal layer has fine irregularities; the average length (Rsm) of roughness curve elements of the surface of the composite copper member is 550 nm or less; a surface area rate is 1.3 or more and 2.2 or less; and the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less.SELECTED DRAWING: None

Description

The present invention relates to a composite copper member.

The copper foil used for the printed wiring board is required to have adhesion to the insulating resin base material. In order to improve this adhesiveness, a method has been used in which the surface of the copper foil is roughened by etching or the like to increase the mechanical adhesive force by the so-called anchor effect. However, from the viewpoint of increasing the density of printed wiring boards and transmission loss in the high frequency band, flattening of the copper foil surface has been required. In order to satisfy these conflicting requirements, copper surface treatment methods such as performing an oxidation step and a reduction step have been developed (Patent Document 1). According to the report, the copper foil is pre-conditioned and immersed in a chemical solution containing an oxidizing agent to oxidize the surface of the copper foil to form irregularities of copper oxide, and then immersed in a chemical solution containing a reducing agent to obtain copper oxide. By reducing the amount of water, the unevenness of the surface is adjusted and the roughness of the surface is adjusted. Further, as a method for improving the adhesion in the treatment of copper foil using oxidation / reduction, a method of adding a surface active molecule in the oxidation step (Patent Document 2) or copper using an aminothiazole compound or the like after the reduction step. A method of forming a protective film on the surface of a foil (Patent Document 3) has been developed.
The distance between each convex portion of the unevenness of 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 roughening treatment layer repeats diffuse reflection in the fine uneven structure. As a result, it decays. Therefore, the roughened surface functions as an absorption layer that absorbs light, and the surface of the roughened surface is darkened to black, brown, or the like as compared with that before the roughening treatment. Therefore, it is known that the roughened surface of the copper foil is also characterized in its color tone, and the value of the lightness L ^* of the L ^* a ^* b ^* color system is 25 or less (Patent Document 4). ).

On the other hand, a method of plating the uneven surface of the roughened surface of the copper foil to increase the mechanical adhesive force has also been reported, but in order to prevent the unevenness from being smoothed by leveling, the fine uneven shape is filled. It remains on the plating film having metal particles distributed in a discrete manner so as not to be present (Patent Document 5).

Further, when the surface of the roughened copper foil is plated with metal particles, when the metal particles are ferromagnetic, the printed wiring board produced using the plated copper foil is in the high frequency band. It was also known that the transmission loss of the metal plating was exacerbated (Patent Document 6).

International Publication No. 2014/126193 Special Table 2013-534054 Japanese Unexamined Patent Publication No. 8-97559 JP-A-2017-48467 Japanese Unexamined Patent Publication No. 2000-151096 Japanese Unexamined Patent Publication No. 2018-172790

An object of the present invention is to provide a novel composite copper member.

As a result of diligent research, the inventors of the present application have developed a new metal layer having a uniform thickness and not discrete on the fine irregularities formed of copper and copper oxide, while suppressing the leveling of the surface thereof. Succeeded in producing the composite copper member of. Further, using this composite copper member, we have succeeded in producing a laminate capable of suppressing a transmission loss of a high frequency (for example, 1 GHz or more) current.
The present invention has the following embodiments:
[1] A composite copper member in which a metal layer made of a metal other than copper is formed on fine irregularities containing copper and copper oxide on the surface of at least a part of the copper member.
The surface of the composite copper member on which the metal layer is formed has fine irregularities, the average length (Rsm) of the roughness curve element on 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,
A composite copper member having an average vertical thickness of the metal layer of 15 nm or more and 150 nm or less.
[2] The composite copper member according to [1], wherein the value of the brightness L ^{* on} the surface of the composite copper member is less than 35.
[3] The metal layer contains at least one metal selected from the group consisting of Sn, Ag, Zn, Al, Ti, Bi, Cr, Fe, Co, Ni, Pd, Au and Pt [1]. Or the composite copper member according to [2].
[4] The composite copper member according to any one of [1] to [3], wherein the Rz is 0.25 μm or more and 1.2 μm or less in the fine irregularities on the surface of the composite copper member.
[5] A contour curve is created from the observation results using a confocal scanning electron microscope in the fine irregularities on the surface of the composite copper member, and Rz calculated by the method specified in JIS B 0601: 2001 is 0. The composite copper member according to any one of [1] to [3], which is .25 μm or more and 1.2 μm or less.
[6] The composite copper member according to [5], wherein the confocal scanning electron microscope is OPTELICS H1200 (manufactured by Lasertec Co., Ltd.).

[7] A laminate produced by using the composite copper member according to any one of [1] to [4].
[8] An electronic component manufactured by using the composite copper member according to any one of [1] to [4].

[1A] A copper oxide layer having a lower conductivity than that of the copper member is provided on the surface of at least a part of the copper member, and a metal layer exhibiting ferromagnetism at room temperature is formed on the copper oxide layer. ,
Composite copper member for high frequency transmission used at 1 GHz or higher.
[2A] The composite copper member according to [1A], wherein the purity of the copper forming the copper member is 99% or more.
[3A] The composite copper member according to any one of [1A] and [2A], wherein the metal layer contains at least one metal atom selected from the group consisting of Fe, Co, Cr and Ni.
[4A] In the depth direction analysis by X-ray Photoelectron Spectroscopy (XPS) for the composite copper member on which the metal layer is formed, the depth from the outermost surface to 300 nm in terms of SiO ₂ With respect to the number of Cu atoms and the number of O atoms obtained by continuously measuring the above, the range of the depth in which the ratio of Cu / (Cu + O) is continuously 50% or more and 95% or less is 50 nm or more, [1A] to [ 3A] The composite copper member according to any one of the items.
[5A] The metal atom contained in the metal layer is Ni, and the metal atom is Ni.
The number of Ni atoms obtained by continuously measuring the depth from the outermost surface to 300 nm in terms of SiO ₂ in the depth direction analysis using ion sputtering by XPS for the composite copper member on which the metal layer is formed. The composite copper member according to [4A], wherein the depth range in which the ratio of Ni / (Ni + Cu + O) is continuously 1% or more and 98% or less with respect to the number of Cu atoms and the number of O atoms is 100 nm or more.
[6A] The composite copper member according to [1A] to [5A], wherein the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less.
[7A] On the surface of the composite copper member on which the metal layer is formed, a contour curve is created from the observation results using a confocal scanning electron microscope, and Rz calculated by the method specified in JIS B 0601: 2001. The composite copper member according to any one of [1A] to [6A], wherein is 0.25 μm or more and 1.2 μm or less.
[8A] The composite copper member according to [7A], wherein the confocal scanning electron microscope is OPTELICS H1200 (manufactured by Lasertec Co., Ltd.).

[1B] A resin base material having a dielectric constant of 4 or less is formed on the surface of the composite copper member according to any one of [1] to [6] and [1A] to [8A] on which the metal layer is formed. Laminated body.
[2B] The resin base material is at least one selected from the group consisting of a liquid crystal polymer, a fluororesin, a polyetherimide, a polyetheretherketone, a polyphenylene ether, a polycycloolefin, a bismaleimide resin, and a low dielectric constant polyimide. The laminate according to [1B], which contains a resin.
[3B] A wiring board manufactured from the laminate according to [1B] or [2B].
[4B] An electronic component including the wiring board according to [3B].

[1C] The method for manufacturing the composite copper member according to [1].
The first step of forming fine irregularities on the surface of the copper member by oxidation treatment,
The average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less, the surface of the composite copper member on which the metal layer is formed has fine irregularities, and the roughness curve of the surface of the composite copper member. A metal other than copper is used for plating on the fine uneven portion on the surface of the copper member so that the average length Rsm of the element is 550 nm or less and the surface area ratio is 1.3 or more and 2.2 or less. The second step and
A method for manufacturing a composite copper member including.
[2C] The method for producing a composite copper member according to [1C], wherein the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less.
[3C] The method for producing a composite copper member according to [1C] or [2C], wherein the plating treatment is an electrolytic plating treatment in the second step.

[1D] The method for manufacturing the composite copper member according to [1A].
The first step of forming a copper oxide layer having a lower conductivity than the copper forming the copper member by oxidation treatment on the surface of the copper member, and
A second step of forming a metal layer exhibiting ferromagnetism at room temperature on the copper oxide layer,
A method for manufacturing a composite copper member containing.
[2D] The method for producing a composite copper member according to [1D], wherein the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less.
[3D] The method for producing a composite copper member according to [1D] or [2D], wherein in the second step, a metal layer exhibiting ferromagnetism at room temperature is formed by electroplating.

FIG. 1 is a diagram showing the relationship between the average length (Rsm) of the roughness curve elements and the peel strength (normal state) in Examples 1 to 7 and Comparative Examples 1 to 14. FIG. 2 is a diagram showing the relationship between the surface area ratio and the peel strength (normal state) in Examples 1 to 7 and Comparative Examples 1 to 14. FIG. 3 is a diagram showing the relationship between the brightness L ^* of the L ^* a ^* b ^* color system and the peel intensity (normal state) in Examples 1 to 7 and Comparative Examples 1 to 14. FIG. 4 is a diagram showing the relationship between the average vertical thickness (plating thickness) of the plating layer and ΔE ^* ab in Examples 1 to 7 and Comparative Examples 2 to 14. FIG. 5 is a diagram showing the relationship between the vertical average thickness (plating thickness) and the peel strength (normal state) of the plating layer in Examples 1 to 7 and Comparative Examples 2 to 14. FIG. 6 is a diagram showing the results of transmission loss measurement in Example 2 and Comparative Example 1. FIG. 7 is obtained from the results of depth direction analysis using ion sputtering with XPS on the test pieces of Examples 1 and 5 and Comparative Examples 8 and 13 (Cu number of atoms / (Cu number of atoms + O atoms). It is a figure which shows the number)) by (%). FIG. 8 is obtained from the results of depth direction analysis of the test pieces of Examples 1 and 5 and Comparative Examples 8 and 13 using ion sputtering by XPS (Ni atom number / (Ni atom number + Cu atom number). Number + number of O atoms)) is shown in (%). FIG. 9 is a schematic cross-sectional view of the composite copper members of Example 1 and Comparative Examples 8 and 13, which are estimated from the results of FIGS. 7 and 8.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not necessarily limited thereto. The object, feature, advantage, and idea thereof of the present invention will be apparent to those skilled in the art from the description of the present specification, and those skilled in the art can easily reproduce the present invention from the description of the present specification. it can. The embodiments and specific examples of the invention described below show preferred embodiments of the present invention and are shown for illustration or explanation purposes, and the present invention is described in them. It is not limited. It will be apparent to those skilled in the art that various modifications and modifications can be made based on the description of the present specification within the intent and scope of the present invention disclosed herein.

== Composite copper member ==
One embodiment of the present invention is a composite copper member in which a metal layer made of a metal other than copper is formed on fine irregularities formed of copper and copper oxide on the surface of at least a part of the copper member. A copper member is a material containing Cu as a main component, which is a part of the structure, and includes copper foils such as electrolytic copper foils, rolled copper foils, and copper foils with carriers, copper wires, copper plates, and copper lead frames. Included, but not limited to.

When the copper member is a 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, and more preferably 0.5 μm or more and 50 μm or less.

In the composite copper member according to the embodiment of the present invention, the average length (RSm) of the surface roughness curve element on which the metal layer made of a metal other than copper is formed is 550 nm or less, preferably 450 nm, more preferably 350 nm. It is as follows. Here, RSm represents the average of the lengths (that is, the lengths of contour curve elements: Xs1 to Xsm) in which unevenness for one cycle included in the roughness curve at a certain reference length (lr) occurs. It is calculated by the following formula.
Here, 10% of the arithmetic mean roughness (Ra) is defined as the minimum height of the unevenness, and 1% of the reference length (lr) is defined as the minimum length, and the unevenness for one cycle is defined. As an example, Rsm can be measured and calculated according to "Method for measuring surface roughness of fine ceramic thin film by atomic force microscope (JIS R 1683: 2007)".

The surface area ratio of the surface of the composite copper member in 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. , More preferably 2.0 or less.
Here, the surface area ratio is the ratio of the surface area to the area in a predetermined range. For example, if the surface area ratio is 1, it is in a state of a completely flat surface without surface roughness, and the larger the surface area ratio, the more severe the unevenness of the surface. The area in a predetermined range is equal to the surface area in that range when the surface of the range is flat.
The surface area ratio can be calculated by the following method as an example. The surface of fine irregularities of a composite copper member containing a metal other than copper is observed with an atomic force microscope (AFM) to obtain a shape image of AFM. This is repeated at 10 randomly selected locations, and the surface areas S1, S2, ..., S10 are determined by AFM. Next, the ratio (surface area / area) SR1, SR2, ..., SR10 of these surface areas S1, S2, ..., S10 to the area of each observation area is simply arithmetically averaged to obtain composite copper. The average surface area ratio of the surface of the member can be obtained.

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 a metal other than copper is formed is 35 or less (or less), preferably 30 or less (or less), more preferably. Is 25 or less (or less).
Here, the brightness L ^* is used as one of the indexes for measuring the surface roughness in the L ^* a ^* b ^* color system, and determines the amount of light reflected when the surface of the measurement sample is irradiated with light. It can be measured and calculated. For example, L ^* = 0 represents a diffuse color of black and L ^* = 100 represents a diffuse color of white. The specific calculation method may be in accordance with JIS Z8105 (1982).
When measuring the brightness of the surface of a composite copper member on which a metal layer is formed, when the gap (that is, Rsm) of the uneven portion of the surface is narrow, the amount of light reflected is small, so the brightness value is low and the uneven portion When the gap is wide, the amount of light reflected tends to be large and the brightness value tends to be high.

In the composite copper member according to the embodiment of the present invention, the Rz of the surface on which the metal layer made of a metal other than copper is formed is 1.00 μm or less, preferably 0.90 μm or less, and more preferably 0.80 μm or less. , 0.10 μm or more, preferably 0.15 μm or more, more preferably 0.20 μm or more.
Here, the maximum height roughness (Rz) is the sum of the maximum value of the peak height Zp of the contour curve (y = Z (x)) and the maximum value of the valley depth Zv at the reference length l. Represents.
Rz can be calculated by 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 not copper, but is selected from the group consisting of Sn, Ag, Zn, Al, Ti, Bi, Cr, Fe, Co, Ni, Pd, Au and Pt. It is preferably at least one kind of metal. In particular, in order to have acid resistance and heat resistance, it is preferable to use metals having higher acid resistance and heat resistance than copper, such as Ni, Pd, Au and Pt.

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, and more preferably 20 nm or more and 25 nm or more. If it is too thin, the metal layer cannot uniformly cover the unevenness of the copper oxide layer, the heat resistance deteriorates, and migration is likely to occur. However, if it is too thick, fine irregularities on the surface of the composite copper member will be smoothed by leveling, and the peel strength will also decrease. Therefore, it is preferably 150 nm or less, preferably 128 nm or less, 100 nm or less, 96 nm or less, or 75 nm or less. It is more preferable to have.
The average thickness of the metal other than copper contained in the metal layer in the vertical direction 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 be calculated by melting the composite copper member itself and detecting and measuring only the amount of metal forming the metal layer.

A metal layer made of a metal other than copper may be formed on the surface of the copper member by plating. The plating method is not particularly limited, and plating can be performed by electrolytic plating, electroless plating, vacuum deposition, chemical conversion treatment, or the like. However, since it is preferable to form a uniform and thin plating layer, electrolytic plating is preferable. Hereinafter, the coating treatment including vacuum deposition and chemical conversion treatment is referred to as plating. When performing electroplating copper member surface oxidation treatment, is first oxidized copper surface (CuO) is reduced, since the charge is used to be cuprous oxide (Cu 2 _O) or pure copper, it is plated There will be a time lag before. For example, when performing Ni plating on a copper member, in order to fit the thickness of the above preferred range, the per area of the copper member that electrolytic plating process, the 15C / dm ² or more ~75C / dm ² or less of the charge applied preferably, 25C / dm ² or more ~65C / dm ² or less is more preferable.

In another embodiment of the present invention, in the composite copper member for high frequency transmission used at 1 GHz or higher, a copper oxide layer having a lower conductivity than that of the copper member is formed on the surface of at least a part of the copper member. A metal layer exhibiting ferromagnetism at room temperature is provided on the copper oxide layer.

In the composite copper member for high frequency transmission used at 1 GHz or higher, the copper contained in the copper member is not particularly limited, but high-purity copper such as tough pitch copper or oxygen-free copper (for example, purity 95% or higher, 99% or higher, Or 99.9% or more) is preferable.

Copper oxide layer conductivity lower than copper member includes copper and copper oxide (CuO and / or Cu 2 _O). Since the specific resistance value of pure copper is 1.7 × ^10-8 (Ωm), copper oxide is 1 to 10 (Ωm) and cuprous oxide is 1 × 10 ⁶ to 1 × 10 ⁷ (Ωm). of the molecules forming the copper oxide layer, at least 1%, 5%, 10%, 20%, 30%, if it contains 40% or 50% or more CuO or Cu ₂ O, conductive than copper member It can be defined as a copper oxide layer with a low rate.

The metal layer exhibiting ferromagnetism at room temperature contains metal atoms that can be spontaneously magnetized at room temperature without an external magnetic field. The metal atom is not particularly limited, but atoms such as Fe, Co, Cr, and Ni are preferable. Further, the metal layer exhibiting ferromagnetism at room temperature may contain an alloy containing Fe, Co, Cr, Ni and the like, and an oxide of these metals (for example, chromium (IV) oxide). The metal layer that exhibits ferromagnetism at room temperature is preferably a crystalline metal, alloy, or metal oxide, and contains atoms and molecules such as phosphorus (P) that affect the crystallinity in a weight ratio of 10%, 9 %, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0.3% or more is preferably not contained. When the metal layer exhibiting ferromagnetism at room temperature is composed of Ni, the purity of Ni is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%. , 99.5%, 99.7%, or 99.9% or more is preferable. Therefore, such a metal layer is formed by electroless plating with boron (B) eutectoid, electroless plating with hydrazine or electroplating, instead of electroless plating with high concentration phosphorus eutectoid. Is preferable.

The copper oxide layer having a lower conductivity than the copper member is preferably contained in a form that separates the metal layer that exhibits ferromagnetism at room temperature from the copper member. Due to the presence of such a layer having low conductivity, the influence of the ferromagnetic metal forming the metal layer can be suppressed, and the transmission loss of the alternating current flowing through the copper member (particularly the skin portion thereof) can be suppressed.

The copper oxide layer having a lower conductivity than the copper member can be detected by performing a depth direction analysis using ion sputtering using XPS and continuously measuring the depth from the outermost surface to 300 nm in terms of SiO ₂ . The layer having low conductivity contains Cu atoms and O atoms, and the ratio of the number of atoms of Cu / (Cu + O) is preferably 50% or more, more preferably 55% or more, 60%, or 66.7% or more, 95. % Or less is preferable, and 90% or less, 85% or less, or 80% or less is more preferable. Further, the range of the layer having low conductivity in the depth direction is preferably 25 nm or more, more preferably 50 nm or more, 75 nm or more, and 100 nm or more in terms of SiO ₂ .

The metal layer that exhibits ferromagnetism at room temperature is formed so as to cover the copper oxide layer, and in such an embodiment, depth direction analysis using ion sputtering by XPS is performed, and the surface is up to 300 nm in terms of SiO ₂ from the outermost surface. It can be detected by continuously measuring the depth of. When the metal layer exhibiting ferromagnetism at room temperature contains Ni, Cu / (Ni + Cu + O) is obtained with respect to the number of Ni atoms, Cu atoms, and O atoms obtained by continuously measuring the depth from the outermost surface to 300 nm in terms of SiO _2. The range of the depth in which the ratio of 1% or more and 99% or less is continuously is preferably 100 nm or more in terms of SiO ₂ , and more preferably 150 nm, 200 nm, or 250 nm or more.

== Manufacturing method of composite copper member ==
One embodiment of the present invention is a method for manufacturing a composite copper member, in which a first step of forming fine irregularities on the surface of the copper member by an oxidation treatment and a plating treatment on the surface of the copper member on which the fine irregularities are formed are performed. This is a method for manufacturing a composite copper member including the second step.

First, in the first step, the surface of the copper member is oxidized with an oxidizing agent to form a layer of copper oxide and fine irregularities are formed on the surface. Copper oxides include CuO and CuO ₂ . Prior to this oxidation step, a roughening treatment step such as etching is not necessary, but it may be performed. Further, before the oxidation treatment, an acid cleaning for homogenizing the surface by degreasing treatment and removal of a natural oxide film, or an alkali treatment for preventing the introduction of acid into the oxidation step after the acid cleaning may be performed. The method of alkaline treatment is not particularly limited, but is preferably 0.1 to 10 g / L, more preferably 1 to 2 g / L in an alkaline aqueous solution, for example, a sodium hydroxide aqueous solution at 30 to 50 ° C. for 0.5 to 2 minutes. It should be processed to some extent.

The oxidizing agent is not particularly limited, and for example, an aqueous solution of sodium chlorite, sodium hypochlorite, potassium chlorate, potassium perchlorate or the like can be used. Various additives (for example, phosphates such as trisodium phosphate dodecahydrate) and surface active molecules may be added to the oxidizing agent. Surface active molecules include porphyrin, porphyrin-membered ring, expanded porphyrin, ring-reduced porphyrin, linear porphyrin polymer, porphyrin sandwich coordination complex, porphyrin sequence, silane, tetraorgano-silane, aminoethyl-aminopropyl-trimethoxysilane. , (3-Aminopropyl) Trimethoxysilane, (1- [3- (Trimethoxysilyl) Propyl] Urea) ((l- [3- (Trimethoxysilyl) Propyl] urea)), (3-Aminopropyl) Triethoxy Silane, ((3-glycidyloxypropyl) trimethoxysilane), (3-chloropropyl) trimethoxysilane, (3-glycidyloxypropyl) trimethoxysilane, dimethyldichlorosilane, 3- (trimethoxysilyl) propylmethacrylate, Ethyltriacetoxysilane, triethoxy (isobutyl) silane, triethoxy (octyl) silane, tris (2-methoxyethoxy) (vinyl) silane, chlorotrimethylsilane, methyltrichlorosilane, silicon tetrachloride, tetraethoxysilane, phenyltrimethoxysilane, Examples thereof include chlorotriethoxysilane, ethylene-trimethoxysilane, amine, and sugar.

The oxidation reaction conditions are not particularly limited, but the temperature of the chemical solution for oxidation is preferably 40 to 95 ° C, 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, the surface of the oxidized copper member may be dissolved with a dissolving agent to adjust the unevenness of the surface of the copper member.

The solubilizer used in this step is not particularly limited, but a chelating agent, particularly a biodegradable chelating agent, is preferable, and ethylenediaminetetraacetic acid, diethanolglycine, L-glutamate diacetic acid / tetrasodium, ethylenediamine-N, N'- Examples thereof include disuccinic acid, 3-hydroxy-2, 2'-sodium iminodiacetic acid, methylglycine diacetate 3 sodium, aspartate diacetate 4 sodium, N- (2-hydroxyethyl) iminodiacetic acid disodium, sodium gluconate and the like. it can.

The pH of the chemical solution for dissolution is not particularly limited, but it is preferably alkaline, more preferably pH 8 to 10.5, further preferably pH 9.00 to 10.5, and pH 9.8 to 10. It is more preferably 2.

Further, in the first step, the copper oxide formed on the oxidized copper member may be reduced by using a chemical solution containing a reducing agent (reducing chemical solution) to adjust the number and length of irregularities. Good.

As the reducing agent, DMAB (dimethylamine borane), diborane, sodium borohydride, hydrazine and the like can be used. The chemical solution 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, a composite copper member is manufactured by plating the surface of the copper member on which the fine convex portion is formed with a metal other than copper. As a plating treatment method, a known technique can be used. For example, as a metal other than copper, Sn, Ag, Zn, Al, Ti, Bi, Cr, Fe, Co, Ni, Pd, Au, Pt, or Various alloys can be used. The plating process is not particularly limited, and plating can be performed by electroplating, electroless plating, vacuum deposition, chemical conversion treatment, or the like. Electroplating is preferred for plating because it is preferable to form a uniform and thin plating layer in one embodiment of the present invention. Conventionally, hump-like irregularities are formed on the copper surface of a copper member by copper plating, and layered plating is performed in order to further impart heat resistance and chemical resistance. However, in the present invention, the copper surface is formed by oxidation treatment. The copper surface of a copper member containing copper oxide and having uniform and fine irregularities is plated.

In the case of electrolytic plating, nickel plating, nickel alloy plating and the like are preferable. Examples of nickel plating and nickel alloy plating include pure nickel, Ni-Cu alloy, Ni-Cr alloy, Ni-Co alloy, Ni-Zn alloy, Ni-Mn alloy, Ni-Pb alloy, Ni-P alloy and the like.
As a filler of plating ions, for example, nickel sulfate, nickel sulfamate, nickel chloride, nickel bromide, zinc oxide, zinc chloride, diammine dichloropalladium, iron sulfate, iron chloride, chromic anhydride, chromium chloride, sodium chromium sulfate, Copper sulfate, copper pyrophosphate, cobalt sulfate, manganese sulfate, sodium hypophosphite, and the like can be used.
Other additives including pH buffers and brighteners include, for example, sulfonic acid, nickel acetate, citrate, sodium citrate, ammonium citrate, potassium formate, malic acid, sodium thiosulfate, sodium hydroxide, potassium hydroxide, etc. Sodium carbonate, ammonium chloride, sodium cyanide, sodium tartrate, potassium thiosulfate, sulfuric acid, hydrochloric acid, potassium chloride, ammonium sulfate, ammonium chloride, potassium sulfate, sodium sulfate, sodium thiosulfate, sodium thiosulfate, potassium bromide, potassium pyrophosphate , Ethylenediamine, nickel ammonium sulfate, sodium thiosulfate, silicic acid, sodium silicate, strontium sulfate, cresol sulfonic acid, β-naphthol, saccharin, 1,3,6-naphthalene trisulfonic acid, naphthalene (di, tri), sulfon 1-4 Butindiols such as sodium acid, sulfonic acid and sulfic acid, coumarin and sodium lauryl sulfate are used.
In nickel plating, the bath composition thereof is, for example, nickel sulfate (100 g / L or more to 350 g / L or less), sulfamine nickel (100 g / L or more to 600 g / L or less), nickel chloride (0 g / L or more to 300 g / L or less). The following) and a mixture thereof are preferable, but even if sodium citrate (0 g / L or more to 100 g / L or less) or boric acid (0 g / L or more to 60 g / L or less) is contained as an additive. Good.

In the case of electroless nickel plating, it is preferable to perform treatment using a catalyst. As the catalyst, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and salts thereof are preferably used. By performing the treatment with a catalyst, a uniform metal layer in which particles are not scattered can be obtained. As a result, the heat resistance of the composite copper foil is improved. In the case of electroless nickel plating, it is preferable to use a reducing agent in which copper and copper oxide do not have catalytic activity. Examples of the reducing agent in which copper and copper oxide do not have catalytic activity include hypophosphates such as sodium hypophosphite.

As described above, by performing the first step and the second step on the copper member, the composite copper member is formed with a metal layer made of a metal other than copper on the surface of at least a part of the copper member. The surface of the composite copper member having a metal layer made of a metal other than copper has fine irregularities, the Rsm is 550 nm or less, the surface area ratio is 1.3 or more and 2.2 or less, and the metal layer is in the vertical direction. A composite copper member having an average thickness of 12 nm or more and 150 nm or less or 15 nm or more and 150 nm or less can be produced.

As long as the technical features of the present invention are not impaired, the composite copper member produced in these steps is subjected to a coupling treatment using a silane coupling agent or the like, a molecular bonding treatment, or a rust prevention treatment using benzotriazoles or the like. You may.

== How to use composite copper member ==
The composite copper member of the present invention can be used for electronic parts as a copper foil used for a printed wiring board, a copper wire wired to a substrate, a copper foil for a LIB negative electrode current collector, and the like.

For example, a laminated board is produced by adhering the composite copper foil according to the present invention in layers to a resin base material, and then the composite copper foil is patterned to produce a printed wiring board on which wiring is formed. Can be used for. The type of resin contained in the resin base material in this case is not particularly limited, but polyphenylene ether (PPE), epoxy, polyphenylene oxide (PPO), polybenzoxazole (PBO), polytetrafluoroethylene (PTFE), and liquid crystal polymer (PPE). LCP), or triphenylfosite (TPPI), fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, bismaleimide resin, low dielectric constant polyimide, or a mixed resin thereof is preferable. The resin base material may further contain an inorganic filler or glass fiber. As an example of the resin base material, MEGTRON6 (R5670KJ; manufactured by Panasonic Corporation; dielectric constant 3.71 (1 GHz)) composed of 20 to 70% by weight of polyphenylene ether (PPE), 0 to 20% by weight of silica, and 30 to 70% of glass fiber. ).
The dielectric constant of the resin substrate can be measured by a known method, for example, IPC TM (The Institute for Interconnecting and Packaging Electronic Circuits Test Method) -650 2.5.5.5 or IPC TM-650 2.5. It can be measured according to a standard such as .5.9.
By laminating the composite copper foil according to the present invention on a resin substrate having a low dielectric constant (for example, 5 or less, 4.5 or less, 4 or less, 3.5 or less, or 3 or less), a high frequency (for example, 1 GHz or more) can be obtained. It is possible to suppress the transmission loss of the current (5 GHz or more, or 10 GHz or more).

Further, by using the composite copper foil according to the present invention for the LIB negative electrode current collector, the adhesion between the copper foil and the negative electrode material is improved, and a good lithium ion battery with little capacity deterioration can be obtained. The negative electrode current collector for a lithium ion battery can be manufactured according to a known method. For example, a negative electrode material containing a carbon-based active material is prepared and dispersed in a solvent or water to prepare an active material slurry. After applying this active material slurry to the composite copper foil according to the present invention, it is dried to evaporate the solvent and water. Then, it is pressed, dried again, and then the negative electrode current collector is formed into a desired shape. The negative electrode material may contain silicon, a silicon compound, germanium, tin, lead, etc., which have a theoretical capacity larger than that of the carbon-based active material. Further, as the electrolyte, not only an organic electrolytic solution in which a lithium salt is dissolved in an organic solvent but also a polymer composed of polyethylene oxide, polyvinylidene fluoride or the like may be used. The composite copper foil according to the present invention can be applied not only to a lithium ion battery but also to a lithium ion polymer battery.

<1. Manufacture of composite copper foil ＞
In Comparative Examples 5 to 14 and Examples 1 to 6, a shiny surface of DR-WS (manufactured by Furukawa Electric Co., Ltd., thickness: 18 μm) was used as the copper foil. In Example 7, the same DR-WS, but a matte surface was used. In Comparative Examples 1 to 4, a matte surface of FV-WS (manufactured by Furukawa Electric Co., Ltd., thickness: 18 μm) that had already been roughened and plated was used. The copper foils of Comparative Examples 1 and 5 were not subjected to surface treatment such as oxidation treatment, reduction treatment, and plating treatment according to the present invention. In Comparative Examples 2 to 4, the commercially available FV-WS plating layer was once peeled off before use. The peeling was carried out by immersing in hydrochloric acid at a liquid temperature of 50 ° C. at 234 ml / L for 6 minutes.

(1) Pretreatment [Alkaline degreasing treatment]
The copper foil was immersed in a sodium hydroxide aqueous solution at a liquid temperature of 50 ° C. and 40 g / L for 1 minute, and then washed with water.
[Acid cleaning treatment]
The copper foil subjected to the alkaline degreasing treatment was immersed in a sulfuric acid aqueous solution having a liquid temperature of 25 ° C. and 10% by weight for 2 minutes, and then washed with water.
[Pre-dip processing]
The acid-washed copper foil was immersed in a chemical solution for predip at a liquid temperature of 40 ° C. and sodium hydroxide (NaOH) of 1.2 g / L for 1 minute.

(2) The copper foil was subjected to oxidation treatment alkali treatment, Examples 1 to 7 and Comparative Examples 9-13 oxidized aqueous solution _{(NaClO 2 60g / L; NaOH} 9g / L; 3- glycidyloxypropyltrimethoxysilane Oxidation treatment was carried out at 73 ° C. for 2 minutes at 2 g / L). Comparative Example 14 was oxidized with an aqueous solution for oxidation treatment (NaClO ₂ 37.5 g / L; NaOH 100 g / L) at 73 ° C. for 4 minutes. After these treatments, the copper foil was washed with water.

In Comparative Example 9, after the oxidation treatment, the mixture was immersed in a reducing agent (dimethylamine borane 5 g / L; sodium hydroxide 5 g / L) for 1 minute at room temperature to perform the reduction treatment.

(3) Plating Treatment In Examples 1 to 7 and Comparative Examples 11 to 14, the electrolytic solution for nickel plating (nickel sulfate 240 g / L; nickel chloride 45 g / L; citrate 3) was applied to the oxidized copper foil. Electroplating was performed using sodium (20 g / L) (current density 0.5 A / dm ² per copper foil area). In Comparative Examples 3, 4, 6 to 8, electrolytic plating was performed using the same electrolytic solution for nickel plating without performing oxidation treatment. The processing times are 50 seconds (Example 1), 60 seconds (Example 2), 70 seconds (Example 3), 80 seconds (Example 4), 100 seconds (Example 5), and 120 seconds (Example 5), respectively. 6), 130 seconds (Example 7), 20 seconds (Comparative Example 3), 60 seconds (Comparative Example 4), 10 seconds (Comparative Example 6), 20 seconds (Comparative Example 7), 60 seconds (Comparative Example 8) , 40 seconds (Comparative Example 11), 150 seconds (Comparative Example 12), 350 seconds (Comparative Example 13), 220 seconds (Comparative Example 14).

(4) Coupling Treatment For Examples 1 to 7 and Comparative Examples 2 to 14, the copper foil was treated with 3-aminopropyltriethoxysilane (1% by weight) for 1 minute at room temperature, and then 1 at 110 ° C. Separate baking was performed.

For Examples and Comparative Examples, a plurality of test pieces were prepared under the same conditions.
As for the evaluation surface, Comparative Examples 6 to 14 and Examples 1 to 6 were surface-treated shiny surfaces, Examples 7 and Comparative Examples 2 to 4 were surface-treated matte surfaces, and Comparative Example 1 was roughened. , The plated surface (matte surface) and the shiny surface were used in Comparative Example 5.

<2. Calculation of Rz>
Contour curves were created from the observation results of the test pieces of Examples and Comparative Examples using a confocal scanning electron microscope OPTELICS H1200 (manufactured by Lasertec Co., Ltd.), and Rz was calculated by the method specified in JIS B 0601: 2001. .. As the measurement conditions, the scan width was 100 μm, the scan type was an area, the Light source was Blue, and the cutoff value was 1/5. The object lens was set to x100, the contact lens was set to x14, the digital zoom was set to x1, the Z pitch was set to 10 nm, data was acquired at three locations, and Rz was the average value of the three locations.

<3. Measurement of RSm and surface area ratio>
The RSm and surface area ratio of the test pieces of Examples and Comparative Examples were observed with an atomic force microscope (AFM: Atomic Force Microscope) and calculated according to JIS R 1683: 2007. Only Comparative Example 1 was calculated with Ra = 150 nm.
Equipment: Made by Hitachi High-Tech Science
Probe station AFM5000II
Connection model: AFM5300E
Cantilever: SI-DF40
Set using the automatic setting function in AFM5000II
(Amplitude attenuation rate, scanning frequency, I gain, P gain, A gain, S gain)
Scanning area: 5 μm square
Number of pixels: 512 x 512
Measurement mode: DFM
Measurement field of view: 5 μm
SIS mode: Not used
Scanner: 20 μm Scanner Measuring method: Measured with third-order correction.
◆ RSm → Average cross-section analysis (lr = 5μm)
◆ Surface area ratio → Surface roughness analysis

<4. Brightness L ^* Measurement>
The measurement of the brightness L ^* in the L ^* a ^* b ^* color system is the spectrocolor difference meter NF999 manufactured by Nippon Denshoku Industries Co., Ltd. (illumination condition: C; viewing angle condition: 2; measurement item: L ^* a ^* b ^* ) Was used.

<5. Plating thickness measurement, surface elemental analysis and elemental analysis at a given depth>
5.1 Measurement of plating thickness As a method of measuring the average thickness in the vertical direction of plating, a copper member is dissolved in 12% nitrate, and the solution is used as an ICP emission spectrometer 5100 SVDV ICP-OES (Agilent Technology Co., Ltd.). The metal concentration was measured by analysis using (manufactured by), and the thickness of the metal layer as a layer was calculated by considering the density of the metal and the surface area of the metal layer.
5.2 Surface elemental analysis As surface elemental analysis, copper and metals other than copper are detected on the surface on which the metal layer is formed by performing the outermost surface Narrow analysis in the following steps using QuanteraSPM (manufactured by ULVAC-PHI). I checked if I could do it.
(1) Survey spectrum
First, the elements were detected under the following conditions.
X-ray beam diameter: 100 μm (25w15kV)
Path energy: 280 eV, 1 eV Step line analysis: φ100 μm × 700 μm
Accumulation number 6 times (2) Now spectrum
For the elements detected in (1), the Narrow Spectrum is acquired under the following conditions, and the ratio of each detected component is calculated as a quantitative value when the total amount of elements other than N and C among the detected components is 100%. did.
X-ray beam diameter: 100 μm (25w15kV)
Path energy: 112 eV, 0.1 eV Step line analysis: φ100 μm × 700 μm
5.3 Analysis in the depth direction Using the obtained test pieces of Examples and Comparative Examples, elemental analysis in the depth direction was performed under the following conditions.
The elements analyzed were carbon (C), oxygen (O), copper (Cu) and nickel (Ni), and the concentration (at%) of each element was calculated with the total of these elements as 100%. Cu / Cu + O (%) and Ni / Ni + Cu (%) were calculated from the calculated element concentrations. The depth is expressed as a distance (nm) in terms of SiO ₂ .
The XPS apparatus, using a ULVAC-PHI Co. 5600MC, ultimate vacuum: 5.7 × 10 ^{- 9} Torr, excitation source: monochromatic AlK, output: 210W, detection area: 800Myuemufai, incident angle: 45 °, Extraction angle: 45 degrees, no neutralizing gun, and measured under the following sputtering conditions.
Ion species: Ar +
Acceleration voltage: 3kV
Sweep area: 3mm x 3mm
Rate: The ratio of Cu atom number / Cu atom number + O atom number (FIG. 7) and the ratio of Ni atom number / Ni atom number + Cu atom number + O atom number (FIG. 8) in terms of SiO ₂ are shown.
Further, FIG. 9 shows a schematic view of the vertical cross sections of Example 1 and Comparative Examples 8 and 13 estimated from the obtained data. In Example 1, the Ni layer and the copper member are separated by the copper oxide layer, whereas in Comparative Example 8, the copper oxide layer does not exist, and the Ni layer is directly laminated on the surface of the copper member. In Comparative Example 13, although the copper oxide layer is present as in Example 1, the Ni layer is too thick and the copper oxide layer cannot be detected by the depth direction analysis (up to 300 nm) by XPS.

<6. Measurement of heat resistance of copper foil>
The heat resistance of the test pieces of Examples and Comparative Examples was examined by changing the color due to heating. After measuring the color difference (L ^* , a ^* , b ^* ) of the test piece before the heat treatment, the test piece was treated in an oven at 225 ° C. for 30 minutes, and the color difference of the test piece after the heat treatment was measured. From the obtained values, ΔE ^* ab was calculated according to the following formula.
[Number 2]
ΔE ^* ab = [(ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ] ^1/2

<7. Measurement of peel strength under normal conditions and after acid resistance test>
In addition, the peel strength of the test pieces of Examples 1 to 6 and Comparative Examples 1 to 14 was measured before and after the acid treatment. Specifically, first, prepreg R5670KJ (manufactured by Panasonic Corporation, thickness 100 μm) is laminated on each test piece, and a press pressure of 2.9 MPa, a temperature of 210 ° C., and a press time of 120 minutes are used using a vacuum high-pressure press machine. A laminate was obtained by heat-pressing under the conditions of.
Similarly, the peel strength before and after the acid treatment was measured using Adflema NC0207. Adflema NC0207 (manufactured by Namics) is laminated on each test piece, and the laminate is heat-bonded using a vacuum high-pressure press under the conditions of a press pressure of 1.0 MPa, a temperature of 200 ° C., and a press time of 1 hour. Obtained.
For Examples and Comparative Examples, a plurality of laminates were prepared under the same conditions. In order to examine the resistance to acid, one of the laminates was used as it was (normal state), and the other was used as a measurement sample after being immersed in an acid solution (after an acid resistance test). The acid solution immersion was performed by immersing the laminate in 4N HCl at 60 ° C. for 90 minutes. The peel strength (kgf / cm) was measured for these measurement samples by a 90 ° peeling test (Japanese Industrial Standards (JIS) C5016).

<8. Measurement of high frequency characteristics>
After laminating the resin base material prepreg R5670KJ (manufactured by Panasonic Corporation) on the test pieces of Example 2 and Comparative Example 1 by thermal pressure molding, a sample for measuring transmission characteristics was prepared and the transmission loss in the high frequency band was measured. .. The transmission characteristics were evaluated using a known stripline resonator method suitable for measurement in the 0 to 40 GHz band. Specifically, the S21 parameter was measured under the following conditions without a coverlay film.
Measurement conditions: Microstrip structure; Base material prepreg R5670KJ; Circuit length 100 mm; Conductor width 250 μm; Conductor thickness 28 μm; Base material thickness 100 μm; Characteristic impedance 50 Ω
The results are shown in FIG.
Further, after laminating the resin base material Adflema NC0207 (manufactured by Namics) on the test pieces of Examples 1 to 7 and Comparative Examples 1 to 14 by thermal pressure molding, a sample for measuring transmission characteristics was prepared and in the high frequency band. The transmission loss was measured. The transmission characteristics were evaluated using a known stripline resonator method suitable for measurement in the 0 to 40 GHz band. Specifically, the S21 parameter was measured under the following conditions without a coverlay film.
Measurement conditions: Microstrip structure; Base material prepreg Adflema NC0207; Circuit length 200 mm; Conductor width 280 μm; Conductor thickness 28 μm; Base material thickness 100 μm; Characteristic impedance 50 Ω

<9. Result>
The results are shown in Table 1 and FIGS. 1-9.

In Comparative Example 1, RSm was large, fine irregularities were not formed, and L ^* was high. Since RSm is large and the surface area ratio is high, it is considered that the increase in surface area is not dense in the lateral direction but large in the height direction, and Rz is large, which is actually due to the influence of the skin effect as shown in FIG. The high frequency characteristics have deteriorated. It is probable that in Comparative Examples 6 and 7, adhesion could not be obtained because RSm was large and the surface area ratio was small. In Comparative Example 9, since there was no plating, heat-resistant discoloration (ΔE ^* ab) was large. In Comparative Example 10, there was no plating, only oxidation treatment was performed, and CuO was the main component in the fine irregularities, so that the peel strength was lowered in the acid resistance test. In Comparative Example 11, the heat-resistant discoloration was large because the plating thickness was insufficient. In Comparative Example 12, the plating was too thick and leveling occurred, resulting in a large RSm and a small surface area ratio, resulting in a decrease in peel strength. In Comparative Example 14, the surface area ratio was too large, so that the plating was not uniform and heat-resistant discoloration occurred.
On the other hand, the average length (Rsm) of the surface roughness curve element is 550 nm or less (Fig. 1), the surface area ratio is 1.3 or more and 2.2 or less (Fig. 2), and the metal layer is in the vertical direction. The composite copper foils of Examples 1 to 7 have a high average thickness of 15 nm or more and 150 nm or less (FIG. 5) and a lightness L ^* value of less than 35 (FIG. 3), and have high peel strength and heat-resistant discoloration (ΔE). ^* Ab) was small (Fig. 4), and the peel strength did not decrease even after the acid resistance test. In addition, the high frequency characteristics of Example 2 were also good.

In Comparative Examples 2, 5 and 10, the heat resistance was low because the metal layer was not provided. In Comparative Example 13, the metal layer exhibiting ferromagnetism at room temperature was too thick to cause transmission loss, and in Comparative Examples 7 and 8, the metal layer exhibiting ferromagnetism at room temperature was directly present without the convex portion containing copper oxide. Since it was laminated on the copper foil, transmission loss occurred. In Comparative Examples 1 to 4, Rz was large, and a transmission loss occurred due to the skin effect. On the other hand, in Examples 1, 2 and 5, the metal layer exhibiting ferromagnetism at room temperature has an appropriate thickness, and the conductivity between the metal layer and the copper portion through which the current flows is higher than that of the copper member. Due to the presence of the low copper oxide layer, the transmission loss of the high frequency current of 10 GHz was small (FIGS. 7-9).

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a novel composite copper member, a laminate and an electronic component using the same, a composite copper member for high frequency transmission, and a laminate for high frequency transmission and an electronic component for high frequency transmission using the same. I can now do it.

<1. Manufacture of composite copper foil ＞
Comparative Examples 5 to 14 and Examples 1 to 6 have a shiny surface (S surface) (glossy surface, which is flat when compared with the opposite surface) of DR-WS (manufactured by Furukawa Electric Co., Ltd., thickness: 18 μm) as a copper foil . The surface that is.) Was used. In Example 7, although it was also DR-WS, a matte surface (M surface) (matte surface, which was rough when compared with the opposite surface) was used. In Comparative Examples 1 to 4, a matte surface of FV-WS (manufactured by Furukawa Electric Co., Ltd., thickness: 18 μm) that had already been roughened and plated was used. The copper foils of Comparative Examples 1 and 5 were not subjected to surface treatment such as oxidation treatment, reduction treatment, and plating treatment according to the present invention. In Comparative Examples 2 to 4, the commercially available FV-WS plating layer was once peeled off before use. The peeling was carried out by immersing in hydrochloric acid at a liquid temperature of 50 ° C. at 234 ml / L for 6 minutes.

Claims (23)

A composite copper member in which a metal layer made of a metal other than copper is formed on fine irregularities containing copper and copper oxide on the surface of at least a part of the copper member.
The surface of the composite copper member on which the metal layer is formed has fine irregularities, the average length (Rsm) of the roughness curve element on 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,
A composite copper member having an average vertical thickness of the metal layer of 15 nm or more and 150 nm or less. The composite copper member according to claim 1 or 2, wherein the value of the brightness L ^{* on} the surface of the composite copper member is less than 35. 13. Of claims 1-3, the metal layer comprises at least one metal selected from the group consisting of Sn, Ag, Zn, Al, Ti, Bi, Cr, Fe, Co, Ni, Pd, Au and Pt. The composite copper member according to any one item. A contour curve is created from the observation results using a confocal scanning electron microscope on the fine irregularities on the surface of the composite copper member, and the Rz calculated by the method specified in JIS B 0601: 2001 is 0.25 μm or more. The composite copper member according to any one of claims 1 to 4, which is 1.2 μm or less. The composite copper member according to claim 4, wherein the confocal scanning electron microscope is OPTELICS H1200 (manufactured by Lasertec Co., Ltd.). A copper oxide layer having a lower conductivity than that of the copper member is provided on the surface of at least a part of the copper member, and a metal layer exhibiting ferromagnetism at room temperature is formed on the copper oxide layer.
Composite copper member for high frequency transmission used at 1 GHz or higher. The composite copper member according to claim 6, wherein the purity of the copper forming the copper member is 99% or more. The composite copper member according to any one of claims 6 or 7, wherein the metal layer contains at least one metal atom selected from the group consisting of Fe, Co, Cr and Ni. In the depth direction analysis by X-ray photoelectron spectroscopy for the composite copper member on which the metal layer is formed, the Cu atomic number and O obtained by continuously measuring the depth from the outermost surface to 300 nm in terms of SiO ₂ The composite copper member according to any one of claims 6 to 8, wherein the depth range in which the ratio of Cu / (Cu + O) is continuously 50% or more and 95% or less with respect to the number of atoms is 50 nm or more. The metal atom contained in the metal layer is Ni.
The number of Ni atoms obtained by continuously measuring the depth from the outermost surface to 300 nm in terms of SiO ₂ in the depth direction analysis using ion sputtering by XPS for the composite copper member on which the metal layer is formed. The composite copper member according to claim 9, wherein the depth range in which the ratio of Ni / (Ni + Cu + O) is continuously 1% or more and 98% or less with respect to the number of Cu atoms and the number of O atoms is 100 nm or more. The composite copper member according to claim 6 to 10, wherein the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less. On the surface of the composite copper member on which the metal layer is formed, a contour curve is created from the observation results using a confocal scanning electron microscope, and the Rz calculated by the method specified in JIS B 0601: 2001 is 0. The composite copper member according to any one of claims 6 to 11, which is 25 μm or more and 1.2 μm or less. The composite copper member according to claim 12, wherein the confocal scanning electron microscope is OPTELICS H1200 (manufactured by Lasertec Co., Ltd.). A laminated body in which a resin base material having a dielectric constant of 4 or less is laminated on the surface of the composite copper member according to any one of claims 1 to 13 on which the metal layer is formed. The resin substrate contains at least one resin selected from the group consisting of liquid crystal polymers, fluororesins, polyetherimides, polyetheretherketones, polyphenylene ethers, polycycloolefins, bismaleimide resins, and low dielectric constant polyimides. , The laminate according to claim 14. A wiring board manufactured from the laminate according to claim 14 or 15. An electronic component including the wiring board according to claim 16. The method for manufacturing a composite copper member according to claim 1.
The first step of forming fine irregularities on the surface of the copper member by oxidation treatment,
The average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less, the surface of the composite copper member on which the metal layer is formed has fine irregularities, and the roughness curve of the surface of the composite copper member. A metal other than copper is used for plating on the fine uneven portion on the surface of the copper member so that the average length Rsm of the element is 550 nm or less and the surface area ratio is 1.3 or more and 2.2 or less. The second step and
A method for manufacturing a composite copper member including. The method for producing a composite copper member according to claim 18, wherein the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less. The method for manufacturing a composite copper member according to claim 18 or 19, wherein in the second step, the plating treatment is an electrolytic plating treatment. The method for manufacturing a composite copper member according to claim 6.
The first step of forming a copper oxide layer having a lower conductivity than the copper forming the copper member by oxidation treatment on the surface of the copper member, and
A second step of forming a metal layer exhibiting ferromagnetism at room temperature on the copper oxide layer,
A method of manufacturing a composite copper member, including. The method for producing a composite copper member according to claim 21, wherein the average thickness of the metal layer in the vertical direction is 15 nm or more and 150 nm or less. The method for producing a composite copper member according to claim 21 or 22, wherein in the second step, the metal layer exhibiting ferromagnetism at room temperature is formed by the electrolytic plating treatment.