TWI878462B - Composite copper structure with voids, carrier metal foil, laminate, printed wiring board manufacturing method, resin substrate manufacturing method and composite copper structure manufacturing method - Google Patents

Abstract

A composite copper member is provided. A layer containing copper oxide is formed on at least a portion of a surface of the copper member, and voids exist in the layer containing copper oxide.

Description

Composite copper structure with voids, carrier metal foil, laminate, printed wiring board manufacturing method, resin substrate manufacturing method and composite copper structure manufacturing method

The present invention relates to a composite copper component having voids.

Copper foil used for printed wiring boards needs to have good adhesion to the insulating resin substrate. In order to improve this adhesion, there is a method of roughening the surface of the copper foil by etching, that is, improving the mechanical adhesion by the so-called anchor effect. On the other hand, from the perspective of high density of printed wiring boards or transmission loss in high frequency bands, the surface of the copper foil needs to be flattened. In order to meet the above-mentioned opposite requirements, a copper surface treatment method that performs an oxidation step and a reduction step has been developed (International Publication No. 2014/126193). In this method, the copper foil is pre-treated by dipping it in a solution containing an oxidant to oxidize the copper foil surface to form copper oxide bumps, and then dipping it in a solution containing a reducing agent to reduce the copper oxide, thereby adjusting the surface bumps to adjust the surface roughness. In addition, a method of adding interfacial active molecules in the oxidation step as a method for improving the adhesion of copper foil by oxidation and reduction (Japanese Patent Publication No. 2013-534054), and a method of using aminothiazole compounds to form a protective film on the copper foil surface after the reduction step (Japanese Patent Publication No. 8-97559).

Generally speaking, the adhesion between resin and metal is related to 1) physical bonding force generated by intermolecular forces between resin and metal or 2) chemical bonding force generated by covalent bonds between functional groups of resin and metal in addition to mechanical adhesion. In order to achieve low capacitance and low dissipation factor, the proportion of OH groups (hydroxyl groups) is reduced in insulating resins used in high-frequency circuits. However, the OH groups of resins are related to bonding with metals, which leads to a weakening of chemical bonding force with copper foil (International Publication No. 2017/150043). Therefore, the adhesion between insulating resins used in high-frequency circuits and copper foil requires stronger mechanical adhesion.

The inventors of this case also developed a composite copper foil, which is a roughened copper foil coated with nickel by electroplating, and has excellent adhesion (International Publication No. 2019/093494).

The present invention provides a novel composite copper component and a printed wiring board using the same, as well as a copper component that acts as a carrier and is metal-plated.

As a result of the inventors' dedicated research, they found that by creating voids in the layer containing copper oxide generated by roughening treatment, the strength of the layer containing copper oxide that forms unevenness is not increased, but reduced. This allows the manufacture of a composite copper component suitable for forming circuits for printed wiring boards and semiconductor package substrates, especially for the Semi-Additive Process (SAP process) or M-SAP (Modified Semi-Additive Process) (MSAP process).

The present invention has the following implementation aspects:

[1] A composite copper component, wherein a layer containing copper oxide is formed on at least a portion of the surface of the copper component, and the layer containing copper oxide has a plurality of voids.

[2] A composite copper component as described in [1], wherein at least a portion of the plurality of voids exist at the interface between the layer comprising copper oxide and the surface of the copper component.

[3] A composite copper component as described in [1] or [2], wherein the peel strength between the layer containing copper oxide and the surface of the copper component is greater than 0.001 kgf/cm and less than 0.30 kgf/cm.

[4] A composite copper component as described in any one of [1] to [3], wherein a scanning electron microscope cross-sectional image is obtained, and when the image is binarized, when measured in a direction parallel to the layer containing copper oxide, the number of voids detected in any 3.8 μm is 30 or more.

[5] A composite copper component as described in any one of [1] to [4], wherein the surface of the layer containing copper oxide of the composite copper component is hot-pressed to a resin substrate under specified conditions to form a laminate, and a scanning electron microscope cross-sectional image of the laminate is obtained. When the image is binarized, when measured in a direction parallel to the laminate surface, the number of voids detected in any 3.8 μm is 30 or more.

[6] A composite copper component as described in [4] or [5], wherein the average distance between the gaps in the binary cross-sectional image is less than 100 nm.

[7] A composite copper component as described in [4] or [5], wherein in the binary cross-sectional image, the distance between the gaps is less than 50 nm and accounts for more than 40% of the total gaps.

[8] A composite copper member as described in any one of [5] to [7], wherein the resin substrate contains at least one insulating resin selected from the group consisting of polyphenylene ether, epoxy resin, polyoxyxylene, polybenzoxazole, polytetrafluoroethylene, liquid crystal polymer, triphenyl phosphite, fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, dimaleimide resin, low dielectric constant polyimide and cyanate resin.

[9] A composite copper component as described in any one of [5] to [8], wherein the specified conditions for the hot pressing are within the range of a temperature of 50°C to 400°C, a pressure of 0 to 20 MPa, and a time of 1 minute to 5 hours.

[10] A composite copper component as described in any one of [5] to [9], wherein the Ra of the surface on which the layer containing copper oxide is formed is greater than 0.03 μm, and the ratio of the Ra of the surface of the copper component peeled off from the resin substrate to the Ra is less than 100%.

[11] A composite copper component as described in any one of [5] to [10], wherein the ratio of the surface area of the copper component peeled off from the resin substrate after hot pressing to the surface area of the surface on which the layer containing copper oxide is formed is less than 100%.

[12] A composite copper component as described in any one of [1] to [11], wherein the layer containing copper oxide contains a metal other than copper.

[13] A composite copper component as described in [12], wherein the metal other than copper is nickel.

[14] A composite copper component as described in any one of [1] to [11], wherein the layer comprising copper oxide comprises a copper plating layer.

[15] A carrier metal foil, comprising a composite copper component as described in any one of [12] to [14], wherein the layer comprising copper oxide is used as a metal foil, and the copper component is used as a carrier relative to the metal foil.

[16] A laminated body, wherein a resin substrate is laminated on at least a portion of the surface of the layer containing copper oxide of the composite copper component as described in any one of [1] to [14].

[17] A laminate as described in [16], wherein the resin substrate contains at least one insulating resin selected from the group consisting of polyphenylene ether, epoxy resin, polyoxyxylene, polybenzoxazole, polytetrafluoroethylene, liquid crystal polymer, triphenyl phosphite, fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, dimaleimide resin, low dielectric constant polyimide and cyanate resin.

[18] A composite copper component as described in any one of [1] to [14], which is used for making a printed wiring board.

[19] The composite copper component as in [18] is used to manufacture printed wiring boards using a semi-additive process or an M-SAP process.

[20] A method for manufacturing a printed wiring board using a composite copper component as described in any one of [1] to [14], comprising: 1) hot pressing a resin substrate on the layer containing copper oxide of the composite copper component under specified conditions; 2) peeling the copper component from the resin substrate under specified conditions to obtain a resin substrate having a part or all of the metal forming the layer containing copper oxide; and 3) copper plating the surface of the resin substrate having a part or all of the metal forming the layer containing copper oxide.

[21] A method for manufacturing a resin substrate having a metal, comprising: 1) a step of hot pressing a resin substrate on the layer containing copper oxide of a composite copper component as described in any one of [1] to [14] under specified conditions; and 2) a step of peeling the copper component from the resin substrate under specified conditions to obtain a resin substrate having a part or all of the metal forming the layer containing copper oxide.

[22] A method for manufacturing a composite copper component, such as the method for manufacturing a composite copper component as described in any one of [1] to [11], comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; and 2) a step of oxidizing the partially coated surface.

[23] A method for manufacturing a composite copper component, which is a method for manufacturing a composite copper component as described in any one of [1] to [11], comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface; and 3) a step of treating the surface of the formed layer containing copper oxide with a modifier, wherein the modifier comprises a compound selected from nickel chloride, zinc chloride, A compound of the group consisting of iron, chromium chloride, ammonium citrate, ammonium chloride, potassium chloride, ammonium sulfate, nickel ammonium sulfate, ethylenediaminetetraacetic acid, dihydroxyethylglycine, tetrasodium L-glutamine diacetate, ethylenediamine-N,N'-disuccinic acid, 3-hydroxy-2,2'-iminodisuccinate sodium, methylglycine diacetate trisodium, aspartic acid diacetate tetrasodium, N-(2-hydroxyethyl)iminodiacetate disodium and sodium gluconate.

[24] A method for manufacturing a composite copper component, such as the method for manufacturing a composite copper component of [12], comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface; and 3) a step of forming a layer containing a metal other than copper on the oxidized surface.

[25] A method for manufacturing a composite copper component, which is the method for manufacturing a composite copper component as described in [12], comprising: 1) a step of oxidizing the surface of the copper component; 2) a step of treating the oxidized surface with a modifier; and 3) a step of forming a layer containing a metal other than copper on the surface treated with the modifier, wherein the modifier comprises a metal selected from nickel chloride, zinc chloride, iron chloride, chromium chloride, , ammonium citrate, ammonium chloride, potassium chloride, ammonium sulfate, nickel ammonium sulfate, ethylenediaminetetraacetic acid, dihydroxyethylglycine, tetrasodium L-glutamine diacetate, ethylenediamine-N,N'-disuccinic acid, 3-hydroxy-2,2'-iminodisuccinate sodium, methylglycine diacetate trisodium, aspartic acid diacetate tetrasodium, N-(2-hydroxyethyl)iminodiacetate disodium and sodium gluconate.

[26] A method for manufacturing a composite copper component, which is the method for manufacturing a composite copper component as described in [12], comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface; 3) a step of treating the oxidized surface with a modifier, and 4) a step of forming a layer containing a metal other than copper on the surface treated with the modifier, wherein the modifier comprises a chlorine-containing metal selected from the group consisting of A compound of the group consisting of nickel chloride, zinc chloride, iron chloride, chromium chloride, ammonium citrate, ammonium chloride, potassium chloride, ammonium sulfate, nickel ammonium sulfate, ethylenediaminetetraacetic acid, dihydroxyethylglycine, tetrasodium L-glutamine diacetate, ethylenediamine-N,N'-disuccinic acid, 3-hydroxy-2,2'-iminodisuccinate sodium, methylglycine diacetate trisodium, aspartic acid diacetate tetrasodium, N-(2-hydroxyethyl)iminodiacetate disodium and sodium gluconate.

[Figure 1] A schematic diagram of an example of a cross section of the composite copper component of the present invention before hot pressing and after peeling.

[Figure 2] The images of the peeled surface after the composite copper foil of the embodiment and the comparative example is pressed onto the resin substrate and peeled off. The numerical value indicates the peeling strength during peeling.

[Figure 3] Cross-sectional images (magnification 30,000 times) observed using a scanning electron microscope (SEM) after the composite copper foils of Examples 1 to 3 and Comparative Examples 2 and 3 were hot-pressed onto a resin substrate. The interface between the layer containing copper oxide and the copper component is represented by a dotted line.

[Figure 4] The cross-sectional image of Figure 3 is inverted and binarized. The highlighted part is the gap. Only the straight line showing the distance between the gaps is added to the image of Example 1.

[Figure 5] A graph showing the number and size of gaps (A), the average distance between gaps (B), and the distribution of the distance between gaps (C) obtained by performing image analysis on Figure 4.

[Figure 6] The cross-section of the composite copper foil of Example 3 and Comparative Example 3 is observed by SEM after hot pressing and peeling off the composite copper foil on the resin substrate.

[Figure 7] A schematic diagram of the cross section in each processing step when a composite copper foil ("transfer + transfer") of one embodiment of the present invention and a known transfer copper foil ("transfer only") are used in the SAP method.

The following uses the attached figures to describe in detail the preferred implementation of the present invention, but is not limited thereto. In addition, according to the description of this specification, a person with ordinary knowledge in the technical field to which the invention belongs understands the purpose, features, advantages and conception of the present invention, and a person with ordinary knowledge in the technical field to which the invention belongs can easily reproduce the present invention according to the description of this specification. The implementation forms and specific embodiments of the invention described below represent the preferred implementation forms of the present invention, which are used for illustration and description, and are not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the invention belongs understands that various modifications can be made based on the description of this specification within the intent and scope of the present invention disclosed in this specification.

Composite copper component: One embodiment of the present invention is a composite copper component, in which a layer containing copper oxide is formed on at least a portion of the surface of the copper component. The copper component is a part of a structure containing copper as a main component. Specifically, the copper component includes copper foil such as electrolytic copper foil, rolled copper foil and carrier copper foil, copper wire, copper plate, copper lead frame, copper powder, etc., but is not limited to them. The copper component is preferably electroplatable. The copper component is preferably made of pure copper with a copper purity of 99.9 mass % or more, more preferably made of annealed copper, deoxidized copper, or oxygen-free copper, and more preferably made of oxygen-free copper with an oxygen content of 0.001 mass % to 0.0005 mass %.

When the ketone component is a copper foil, its thickness is not particularly limited, and 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. When the copper component is a copper plate, its thickness is preferably more than 100 μm. Although not particularly limited, it is preferably 1 mm or more, 2 mm or more, or 10 mm or more, and more preferably 10 cm or less, 5 cm or less, or 2.5 cm or less.

The layer containing copper oxide is formed on the surface of the copper member and contains copper oxide (CuO) and/or cuprous oxide (Cu ₂ O). The layer containing copper oxide can be formed by oxidizing the surface of the copper member. The surface of the copper member is roughened by the oxidation. For the layer containing copper oxide, the shape of the protrusions on the surface of the copper member after oxidation can be adjusted by a solvent. Furthermore, the surface of the layer containing copper oxide can be reduced by a reducing agent. The resistivity of pure copper is 1.7×10 ^-8 (Ωm). In comparison, the resistivity of copper oxide is 1~10 (Ωm) and the resistivity of cuprous oxide is 1×10 ⁶ ~1×10 ⁷ (Ωm). Therefore, the conductivity of the layer containing copper oxide is low. Even if a large amount of the layer containing copper oxide is transferred to the resin substrate, when the composite copper component is used to form a circuit of a printed wiring board or a semiconductor package substrate, it is difficult to produce transmission loss caused by the skinning effect.

The layer containing copper oxide has a plurality of voids. The voids may be connected to the outside or may be closed. It is preferred that even if the resin substrate is hot-pressed on the layer containing copper oxide, the resin substrate does not enter the voids and the voids can be maintained. The voids can be detected in the SEM cross-sectional image of the composite copper component. The voids exist in the layer containing copper oxide, and preferably also include those existing at the interface between the layer containing copper oxide and the surface of the copper component. For example, this interface can be identified by the density difference caused by the composition in the SEM cross-sectional image, or the density difference caused by the presence or absence of the copper crystal structure constituting the copper component (Figure 3). Preferably, more than 50%, more than 60%, more than 70%, more than 80%, more than 90%, more than 95% or 100% of the voids exist at the interface between the layer containing copper oxide and the surface of the copper component, but it is not particularly limited.

Specifically, the voids can be determined from a cross-sectional SEM image of a composite copper component by, for example, the following steps.

1) Obtain a SEM cross-sectional image so that the copper oxide layer is on top and the copper component is on the bottom.

2) The area surrounded by copper and copper oxide on the side closest to the copper component on the screen; or the area surrounded by a straight line passing through the vertex of the area surrounded by copper oxide and parallel to the layer containing copper oxide, and a straight line passing through the vertex of the highest convex part of the layer containing copper oxide and parallel to the layer containing copper oxide as the measurement range.

3) After adjusting the image comparison of the measurement range, perform inversion processing to swap the bright and dark parts of the image.

4) Perform automatic binarization and select the area surrounded by copper and copper oxide or the area surrounded by copper oxide.

5) Delete the image with a side length of 1 pixel as noise.

6) The upper left corner of the image is taken as the origin, the downward direction in the image is taken as the X axis, and the rightward direction is taken as the Y axis. The region (1) selected by automatic binarization where X=maximum and Y=minimum is taken as the starting point, and the region at the closest distance in the Y axis direction is taken as region (2). The region closest to region (2) in the Y axis direction is taken as region (3), and then regions (4)~(N) are determined in the same manner until Y=maximum in the measurement range. Each region (1)~(N) determined here is a gap. Alternatively, the gap can also be determined by the same manner from the cross-sectional SEM image of the composite copper component after layering the resin substrate. Binarization is to process the image by dividing the lightness and darkness of the image by a specified threshold, with the value above the threshold being 1 and the value below the threshold being 0. Binarization can be performed by the OTSU method (discriminant analysis method), Sauvola method, Goto method, etc.

The maximum horizontal chord length of the void is preferably a size that can be detected when a SEM cross-sectional image with a magnification of 30,000 times and a resolution of 1024×768 pixels is binarized. Preferably, the side length is 500 nm or less, 400 nm or less, 300 nm or less, 200 nm or less, 100 nm or less, or 50 nm or less, and the side length is 4 nm or more, 5 nm or more, 10 nm or more, 15 nm or more, 20 nm or more, 25 nm or more, 50 nm or more, 100 nm or more, or 200 nm or more, but is not particularly limited. In the binarized SEM cross-sectional image, when measured in a direction parallel to the surface on which the layer containing copper oxide is formed, the number of voids in any 3.8 μm is preferably 25 or more, 30 or more, 40 or more, or 50 or more, and 500 or less, 400 or less, 300 or less, 200 or less, 100 or less, 90 or less, 80 or less, 70 or less, or 60 or less. In addition, the distance between the voids can also be calculated on the image to calculate the distance between the voids. The average distance between the voids is preferably 200 nm or less, 150 nm or less, 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less, or 50 nm or less, and 40 nm or more, 30 nm or more, 20 nm or more, or 10 nm or more. Furthermore, the distance distribution between the gaps is preferably such that the ratio of the gaps below 50nm accounts for 35%, 40%, 45% or more than 50% of the total gaps.

The presence of the voids makes it easier for the layer containing copper oxide to be separated from the copper member. The peel strength between the layer containing copper oxide and the surface of the copper member is preferably 0.30 kgf/cm or less, 0.20 kgf/cm or less, 0.15 kgf/cm or less, and 0.001 kgf/cm or more, 0.002 kgf/cm or more, 0.003 kgf/cm or more, or 0.004 kgf/cm or more, but is not particularly limited. The peel strength can be measured by hot pressing a resin substrate on a layer containing copper oxide, based on a 90-degree peel test (Japanese Industrial Standard (JIS) C5016 "Flexible Printed Wiring Board Test Method"; corresponding international standards IEC249-1: 1982, IEC326-2: 1990).

The layer containing copper oxide may contain metals other than copper. The metal contained is not particularly limited, and may include at least one metal selected from the group consisting of tin, silver, zinc, aluminum, titanium, bismuth, chromium, iron, cobalt, nickel, palladium, gold and platinum. In particular, in order to make it acid-resistant and heat-resistant, it is preferred to include metals with higher acid resistance and heat resistance than copper, such as nickel, palladium, gold and platinum. Metals other than copper can be formed on the surface of the copper component by plating. The plating method is not particularly limited, and examples thereof include electroplating, electroless plating, vacuum evaporation, chemical treatment, etc. It is preferred to form a uniform thin plating layer, so electroplating is preferred. When electroplating is applied to the surface of the copper foil after oxidation treatment, the copper oxide on the surface is first reduced, and a charge is used to form cuprous oxide or pure copper. Therefore, a time delay will occur until the plating is formed, and then the metal forming the metal layer begins to precipitate. The amount of charge varies depending on the type of plating solution or the amount of copper oxide. For example, when nickel plating is applied to a copper component, in order to form its thickness within a preferred range, it is preferred to give a charge of 15C or more and 75C or less per ^dm2 area of the electroplated copper component, and it is more preferred to give a charge of 25C or more and 65C or less. The average thickness in the vertical direction of the metal other than copper formed on the outermost surface of the copper component by plating is not particularly limited, and is preferably 6 nm or more, more preferably 10 nm or more, 14 nm or more, 18 nm or more, or 20 nm or more. However, it is preferably 80 nm or less, more preferably 70 nm or less, or 60 nm or less. In addition, the average thickness in the vertical direction of the metal other than copper contained in the layer containing copper oxide can be calculated by dissolving the layer containing copper oxide with an acidic solution, measuring the amount of metal by ICP analysis, and dividing the measured amount by the area of the composite copper component. Alternatively, it can also be calculated by dissolving the composite copper component itself and measuring only the amount of metal contained in the layer containing copper oxide.

When the surface of the composite copper component having a layer containing copper oxide is thermally press-fitted to a resin substrate, the surface profile of the composite copper component is transferred to the resin substrate. Furthermore, when the composite copper component is peeled off from the resin substrate after thermal press-fitting, the metal contained in the layer containing copper oxide is transferred from the composite copper component to the resin substrate. An embodiment of the composite copper component is shown in FIG. 1.

The resin substrate is a material containing a resin as a main component, which can be used to form circuits such as printed wiring boards and semiconductor package substrates. The resin is not particularly limited and can be a thermoplastic resin or a thermosetting resin, preferably polyphenylene ether (PPE), epoxy resin, polyoxyxylene (PPO), polybenzoxazole (PBO), polytetrafluoroethylene (PTFE), liquid crystal polymer (LCP), triphenyl phosphite (TPPI), fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, dimaleimide resin, low-capacitance polyimide, cyanate resin or a mixed resin thereof. The resin substrate may further contain an inorganic filler or glass fiber.

In order to heat-press the resin substrate to the surface of the composite copper component, for example, after the resin substrate and the composite copper component are closely adhered and layered, they are treated under specified conditions to make the resin substrate and the composite copper component adhere. The specified conditions (such as temperature, pressure, time) can be the conditions recommended by each substrate manufacturer. The specified conditions can be considered as follows, for example.

1) When the resin substrate includes epoxy resin or is formed of epoxy resin, it is preferred to apply a pressure of 0-20 MPa at a temperature of 50°C-300°C for 1 minute-5 hours to hot-press the composite copper component to the resin substrate. For example,

1-1) When the resin substrate is R-1551 (Panasonic), heat it under a pressure of 1MPa to 100℃ and maintain it at that temperature for 5~10 minutes. Then, heat it further under a pressure of 3.3MPa to 170~180℃ and maintain it at that temperature for 50 minutes to perform heat pressing.

1-2) When the resin substrate is R-1410A (manufactured by Panasonic), heat it under a pressure of 1MPa to 130°C and maintain it at that temperature for 10 minutes. Then, heat it further under a pressure of 2.9MPa to 200°C and maintain it at that temperature for 70 minutes to perform heat pressing.

1-3) When the resin substrate is EM-285 (made by EMC), heat it under a pressure of 0.4MPa. After reaching 100℃, increase the pressure to 2.4~2.9MPa and further heat it. After reaching 195℃, maintain the temperature for 50 minutes to perform heat pressing.

1-4) When the resin base material is GX13 (made by Ajinomoto), heat and pressurize at 1.0MPa and maintain at 180℃ for 60 minutes for heat pressing.

2) When the resin substrate includes PPE resin or is formed of PPE resin, it is preferred to apply a pressure of 0 to 20 MPa at a temperature of 50°C to 350°C for 1 minute to 5 hours to hot press the composite copper component to the resin substrate. For example,

2-1) When the resin substrate is R5620 (Panasonic), heat it to 100℃ under a pressure of 0.5MPa while hot pressing it, then increase the temperature and pressure, and maintain it at 2.0~3.0MPa and 200~210℃ for 120 minutes for further hot pressing.

2-2) When the resin substrate is R5670 (Panasonic), heat and press the parts together at 0.49 MPa while heating to 110°C. Then, increase the temperature and pressure and press the parts together at 2.94 MPa and 210°C for 120 minutes.

2-3) When the resin substrate is R5680 (Panasonic), heat to 110°C under 0.5MPa pressure while hot pressing, then increase the temperature and pressure to 3.0~4.0MPa and 195°C for 75 minutes to perform hot pressing.

2-4) When the resin substrate is N-22 (made by Nelco), heat it while applying pressure at 1.6~2.3MPa, maintain it at 177℃ for 30 minutes, then further heat it and maintain it at 216℃ for 60 minutes for heat pressing.

3) When the resin substrate includes PTFE resin or is formed of PTFE resin, it is preferred to apply a pressure of 0-20 MPa at a temperature of 50°C-400°C for 1 minute-5 hours to heat-press the composite copper component to the resin substrate. For example,

3-1) When the resin substrate is NX9255 (Park Electrochemical), heat to 260°C while applying pressure at 0.69MPa, increase the pressure to 1.03~1.72MPa and heat to 385°C, and maintain at 385°C for 10 minutes for heat pressing.

3-2) When the resin substrate is RO3003 (manufactured by Rogers), 50 minutes after the start of pressing (about 220°C), pressurize to 2.4MPa and maintain at 371°C for 30~60 minutes for hot pressing.

The conditions for peeling the copper component from the resin substrate are not particularly limited, and can be performed based on the 90° peeling test (Japanese Industrial Standard (JIS) C5016 "Flexible Printed Wiring Board Test Method"; corresponding to the international standards IEC249-1: 1982, IEC326-2: 1990).

The metal contained in the layer containing copper oxide is transferred to the resin substrate after the copper component is peeled off. The metal transferred to the surface of the resin substrate after the copper component is peeled off can be detected using various methods (such as X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), ICP emission spectroscopy (inductively coupled plasma emission spectroscopy, ICP-OES/ICP-AES)). XPS is a technique that irradiates X-rays at an object and captures the photoelectrons e-emitted by the ionization of the object to perform energy analysis. XPS can be used to detect the type, amount, chemical bonding state, etc. of elements present on the surface of the sample or from the surface to a specified depth (for example, to a depth of 6nm). The analysis point diameter (i.e. the cross-sectional diameter when the analyzable cylindrical part is cut to form a circular cross section) is suitable for more than 1μm to less than 1mm.

The arithmetic mean roughness (Ra) of the surface of the composite copper member formed with a layer containing copper oxide is 0.03 μm or more, preferably 0.04 μm or more, more preferably 0.1 μm or more, and preferably 0.3 μm or less, and more preferably 0.2 μm or less. The maximum height roughness (Rz) of the surface of the composite copper member formed with a layer containing copper oxide is preferably 0.2 μm or more, more preferably 1.0 μm or more, and preferably 2.0 μm or less, and more preferably 1.7 μm or less. If Ra and Rz are too small, the adhesion to the resin substrate is insufficient, and if too large, the fine wiring formability or high-frequency characteristics are poor. Here, the arithmetic mean roughness (Ra) is the average value of the absolute value of Z(x) (i.e., peak height and valley depth) in the profile curve (y=Z(x)) expressed by the following formula in the reference length 1.

The maximum height roughness (Rz) is the sum of the maximum value of the peak height Zp and the maximum value of the valley depth Zv of the profile curve (y=Z(x)) in the reference length 1. Ra and Rz are calculated according to the method specified in JIS B 0601:2001 (based on the international standard ISO4287-1997). The ratio of the Ra after peeling to the Ra before hot pressing of the surface of the composite copper member formed with a layer containing copper oxide is preferably less than 100%, less than 96%, less than 95%, less than 94%, less than 93%, less than 92%, less than 91%, less than 90%, less than 80%, less than 70%, less than 65% or less than 60%. The smaller this ratio is, the more it indicates that the metal forming the layer containing copper oxide has been transferred to the resin substrate.

The ratio of the surface area after peeling of the composite copper component having a layer containing copper oxide to the surface area before hot pressing is preferably less than 100%, less than 98%, less than 97%, less than 96%, less than 95%, less than 94%, less than 93%, less than 92%, less than 91%, less than 90%, less than 80% or less than 75%. The smaller the ratio, the more it indicates that the metal forming the layer containing copper oxide has been transferred to the resin substrate. The surface area can be measured using a conjugate microscope or an atomic force microscope.

In the composite copper member of one embodiment of the present invention, the average length (RSm) of the roughness profile parameter of the surface of the composite copper member on which the layer containing copper oxide is formed is not particularly limited, but is preferably 1500 nm or less, 1400 nm or less, 1300 nm or less, 1200 nm or less, 1100 nm or less, 1000 nm or less, 900 nm or less, 800 nm or less, 750 nm or less, 700 nm or less, 650 nm or less, 600 nm or less, 550 nm or less, 450 nm or less, or 350 nm or less, and is preferably 100 nm or more, 200 nm or more, or 300 nm or more. Here, RSm represents the average length of the concavity generated by one cycle contained in the roughness curve of a reference length (lr) (i.e. the length of the profile curve parameter: Xs1~Xsm), which is calculated using the following formula.

Here, 10% of the arithmetic mean roughness (Ra) is used as the minimum height of the concavity and 1% of the reference length (lr) is used as the minimum length to define the concavity of one cycle. For example, Rsm can be measured and calculated according to the "Surface roughness measurement method of precision ceramic film using atomic force microscope (JIS R 1683: 2007)".

The △E*ab of the surface of the composite copper component before hot pressing and the surface of the copper component after peeling is preferably 13 or more, 15 or more, 20 or more, 25 or more, 30 or more, or 35 or more. The larger the difference, the more it indicates that the metal forming the layer containing copper oxide (i.e., the metal forming the bumps) has been transferred to the resin substrate.

Manufacturing method of composite copper component: One embodiment of the present invention is a manufacturing method of composite copper component, comprising: providing gaps in a layer containing copper oxide so that the layer containing copper oxide can be easily broken from the copper component.

In this step, the method of providing gaps in the layer containing copper oxide so that the layer containing copper oxide can be easily broken from the copper component is not particularly limited, and includes 1) partially coating the surface of the copper component with a coating agent such as a silane coupling agent before oxidation treatment, 2) treating the layer containing copper oxide with a modifying agent such as nickel chloride after oxidation treatment, or a combination of the above methods.

The layer containing copper oxide is preferably formed by treating the surface of the copper component with an oxidizing agent. The oxidizing agent is not particularly limited, and for example, aqueous solutions of sodium chlorite, sodium hypochlorite, potassium chlorate, potassium perchlorate, potassium persulfate, etc. can be used. Various additives (such as phosphates such as trisodium phosphate dodecahydrate) can be added to the oxidizing agent.

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

Before the oxidation treatment, degreasing treatment can be performed, acid washing can be performed to remove the natural oxide film for homogenization treatment, or alkaline treatment can be performed after acid washing to prevent the acid from being brought into the oxidation step. Acid washing can be performed, for example, by immersing the copper surface in 5-20 wt% sulfuric acid at a liquid temperature of 20-50°C for 1-5 minutes and then washing with water. After the acid treatment, in order to reduce uneven treatment and prevent the acid used in the cleaning treatment from mixing into the oxidant, an alkaline treatment can be further performed. The method of alkaline treatment is not particularly limited, and it is preferably possible to use an alkaline aqueous solution of 0.1-10 g/L, and more preferably a 1-2 g/L alkaline aqueous solution. The alkaline aqueous solution, such as a sodium hydroxide aqueous solution, can be treated at 30-50°C for about 0.5-2 minutes. In addition, the layer containing copper oxide can be dissolved with a dissolving solution containing a solvent to adjust the convex portion of the surface of the copper component, and the copper oxide of the layer containing copper oxide can be reduced with a reducing solution containing a reducing agent.

The dissolving agent is not particularly limited, but is preferably a chelating agent, especially a biodegradable chelating agent, such as tetrasodium L-glutamine diacetate (CMG-40), ethylenediaminetetraacetic acid (sodium salt), dihydroxyethylglycine, tetrasodium L-glutamine diacetate, ethylenediamine-N,N'-disuccinic acid, 3-hydroxy-2,2'-iminodisuccinate sodium, methylglycine diacetate trisodium, aspartic acid diacetate tetrasodium, N-(2-hydroxyethyl)iminodiacetate disodium, sodium gluconate, etc.

The reducing agent may be DMAB (dimethylamine borane), diborane, sodium borohydride, hydrazine, etc. In addition, the reducing solution is a liquid containing a reducing agent, an alkaline compound (such as sodium hydroxide, potassium hydroxide, etc.) and a solvent (such as pure water, etc.).

The layer containing copper oxide may contain metals other than copper. Metals other than copper may be contained by, for example, plating the layer containing copper oxide with metals other than copper. The plating method may use known techniques, and metals other than copper may use, for example, tin, silver, zinc, aluminum, titanium, bismuth, chromium, iron, cobalt, nickel, palladium, gold, platinum or various alloys. The plating step is not particularly limited, and plating may be performed by electroplating, electroless plating, vacuum evaporation, chemical treatment, etc. It is preferred to form a uniform thin plating layer, so electroplating is preferred.

In the case of electroplating, nickel plating and nickel alloy plating are preferred. Examples of metals formed by 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, etc. Examples of metal salts used for plating include nickel sulfate, nickel sulfamate, nickel chloride, nickel bromide, zinc oxide, zinc chloride, diamine dichloropalladium, iron sulfate, iron chloride, anhydrous chromic acid, chromium chloride, sodium chromium sulfate, copper sulfate, copper pyrophosphate, cobalt sulfate, manganese sulfate, etc. In nickel plating, the bath composition preferably includes, for example, nickel sulfate (100 g/L or more and 350 g/L or less), nickel sulfamate (100 g/L or more and 600 g/L or less), nickel chloride (0 g/L or more and 300 g/L or less), and mixtures thereof, and may also include sodium citrate (0 g/L or more and 100 g/L or less) or boric acid (0 g/L or more and 60 g/L or less) as an additive.

In the case of electroless nickel plating, electroless plating using a catalyst is preferred. The catalyst may be iron, cobalt, nickel, ruthenium, rhodium, palladium, zirconium, iridium or their salts. By performing electroless plating using a catalyst, the heat resistance of the composite copper foil can be improved.

An embodiment of the method for manufacturing the composite copper component of the present invention comprises 1) a step of partially coating the surface of the copper component with a silane coupling agent; and 2) a step of oxidizing the partially coated surface of the copper component; or, comprises 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface of the copper component; and 3) a step of forming a layer containing a metal other than copper on the surface of the oxidized copper component. By partially coating the surface of the copper component with a coating agent such as a silane coupling agent, the portion is protected from oxidation treatment, and voids are generated in the layer containing copper oxide, especially near the interface with the copper component, so that the layer containing copper oxide becomes easy to break from the copper component. Therefore, the treatment with the silane coupling agent is preferably to coat a portion of the surface of the copper component (for example, 1%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90% or more and less than 100%), and for this purpose, it is preferred to react the silane coupling agent at a concentration of 0.1%, 0.5%, 1% or 2% or more at room temperature for 30 seconds, 1 minute or more than 2 minutes.

The silane coupling agent is not particularly limited and can be selected from silane, tetraorgano-silane, aminoethyl-aminopropyl-trimethoxysilane, (3-aminopropyl)trimethoxysilane, (1-[3-(trimethoxysilyl)propyl]urea), (3-aminopropyl)triethoxysilane, (3-epoxypropyloxypropyl)trimethoxysilane, (3-chloropropyl)trimethoxysilane, silane, (3-epoxypropyloxypropyl) trimethoxysilane, dimethyldichlorosilane, 3-(trimethoxysilyl)propyl methacrylate, ethyltriethoxysilane, triethoxy(isobutyl)silane, triethoxy(octyl)silane, tris(2-methoxyethoxy)(vinyl)silane, chlorotrimethylsilane, methyltrichlorosilane, tetrachlorosilane, tetraethoxysilane, phenyltrimethoxysilane, chlorotriethoxysilane, vinyl-trimethoxysilane, etc. Silane coupling agent treatment can be performed at any time as long as it is performed before oxidation treatment, and can be performed together with degreasing treatment, pickling to remove the natural oxide film for uniform treatment, or alkaline treatment after pickling to prevent acid from being carried into the oxidation step.

One embodiment of the method for manufacturing a composite copper component of the present invention comprises 1) a step of oxidizing the surface of the copper component; and 2) a step of treating the oxidized surface of the copper component with a modifier, or 1) a step of oxidizing the surface of the copper component; 2) a step of treating the oxidized surface of the copper component with a modifier; and 3) a step of forming a layer containing a metal other than copper on the surface of the composite copper component treated with the modifier. It is speculated that by treating with the modifier, a portion of the copper oxide near the interface between the copper component and the layer containing copper oxide is dissolved, generating voids, and the layer containing copper oxide becomes easy to break from the copper component. The modifying agent used to make the layer containing copper oxide easy to break from the copper member is not limited to nickel chloride, and may also be a chloride (zinc chloride, iron chloride, chromium chloride, etc.), an ammonium salt (ammonium citrate, ammonium chloride, ammonium sulfate, nickel ammonium sulfate, etc.), a chelating agent (ethylenediaminetetraacetic acid, dihydroxyethylglycine, tetrasodium L-glutamine diacetate, ethylenediamine-N,N'-disuccinic acid, 3-hydroxy-2,2'-iminodisuccinate sodium, methylglycine diacetate trisodium, aspartic acid diacetate tetrasodium, N-(2-hydroxyethyl)iminodiacetate disodium, sodium gluconate), etc. The treatment with nickel chloride is not particularly limited. It is preferred to immerse the copper component formed with a layer containing copper oxide in a nickel chloride solution (concentration of 45 g/L or more) at room temperature or a temperature higher than room temperature for more than 5 seconds. In addition, not only the treatment with nickel chloride alone, but also the oxidation treatment can be carried out at the same time, and the oxidation treatment can be carried out at the same time as the plating treatment. For example, nickel chloride can be contained in the plating solution, and the copper component formed with a layer containing copper oxide can be immersed in the plating solution for 5 seconds, 10 seconds, 15 seconds, 20 seconds, 30 seconds, 1 minute or 2 minutes before plating. The immersion time can be appropriately changed according to the thickness of the oxide film.

An embodiment of the method for manufacturing the composite copper component of the present invention comprises 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface of the copper component; and 3) a step of treating the oxidized surface of the copper component with a modifier, or, 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface of the copper component; 3) a step of treating the oxidized surface of the copper component with a modifier; and 4) a step of forming a layer containing a metal other than copper on the surface of the copper component treated with the modifier.

Method for using the composite copper component: The composite copper component of the present invention can be used for (1) pressing onto a resin substrate to manufacture a laminate; (2) pressing onto a resin substrate and peeling off to obtain a resin substrate having a part or all of the metal forming a layer containing copper oxide; (3) pressing onto a resin substrate and peeling off in a SAP method or a MSAP method to obtain a resin substrate having a layer containing copper oxide. (4) Copper or a metal other than copper is plated on a layer containing copper oxide to form a metal foil, and a copper component is used as a carrier, and the layer containing copper oxide and the copper or a metal other than copper is used as a metal foil to manufacture a carrier metal foil, etc.

In (1) to (3), the conditions for the resin substrate and the heat pressing to the resin substrate may be the same as or different from the conditions for obtaining the SEM cross-sectional image. In (2) to (3), the conditions for peeling may be the same as or different from the conditions for obtaining the SEM cross-sectional image. In (3), the copper plating method may be electroplating or electroless plating. In (4), the method for applying the coating to the outermost surface of the layer containing copper oxide may be electroplating or electroless plating, and the metal may be an alloy.

<1. Manufacture of composite copper foil>: In Examples 1 to 3, Comparative Examples 2 and 3, the bright side (glossy side, flat side compared to the opposite side) of copper foil (DR-WS, thickness: 18μm) manufactured by Furukawa Electric Co., Ltd. was used. In Comparative Example 1, the matte side of copper foil (FV-WS, thickness: 18μm) manufactured by Furukawa Electric Co., Ltd. was used as the test piece in the untreated state.

(1) Pretreatment: Examples 1 and 2 were immersed in a solution of 5g/L potassium carbonate and 1vol% KBE-903 (3-aminopropyltriethoxysilane; manufactured by Shin-Etsu Silicone Co., Ltd.) at 25°C for 1 minute. Comparative Examples 2, 3 and Example 3 were immersed in a solution of 5g/L potassium carbonate at 25°C for 1 minute.

(2) Oxidation treatment: The pre-treated copper foil is immersed in an oxidant for oxidation treatment. Examples 1 and 2 use a solution of 52.5 g/L sodium chlorite, 18 g/L potassium hydroxide, and 35 g/L potassium carbonate as the oxidant. Example 3 uses a solution of 37.5 g/L sodium chlorite, 10 g/L potassium hydroxide, and 1.5 g/L KBM-403 (3-epoxypropyloxypropyltrimethoxysilane; manufactured by Shin-Etsu Silicone Co., Ltd.) as the oxidant. Comparative Example 2 uses a solution of 53.5 g/L sodium chlorite, 8 g/L potassium hydroxide, 2 g/L potassium carbonate, and 1.5 g/L KBM-403 (3-epoxypropyloxypropyltrimethoxysilane; manufactured by Shin-Etsu Silicone Co., Ltd.) as an oxidant. Comparative Example 3 uses a solution of 195 g/L sodium chlorite, 18 g/L potassium hydroxide, and 0.5 g/L KBM-403 (3-epoxypropyloxypropyltrimethoxysilane; manufactured by Shin-Etsu Silicone Co., Ltd.) as an oxidant. Examples 1 and 2 are immersed in the oxidant at 73°C for 6 minutes, and Example 3 and Comparative Example 2 are immersed in the oxidant at 73°C for 2 minutes. Comparative Example 3 was immersed in an oxidizing agent at 50°C for 1 minute.

(3) Electroplating: After oxidation treatment, Examples 2, 3 and Comparative Example 2 were electroplated using nickel electroplating solution (nickel sulfate 250 g/L; nickel chloride 50 g/L; sodium citrate 25 g/L). Comparative Example 3 was electroplated using nickel electroplating solution (nickel sulfate 250 g/L; boric acid 35 g/L). Example 3 was immersed in nickel electroplating solution for 1 minute before electroplating. Comparative Examples 2, 3 and Examples 2, 3 were electroplated at 50°C and a current density of 0.5 A/dm2 × ⁴⁵ seconds (=22.5 C/ ^dm2 copper foil area).

Regarding the embodiments and comparative examples, several test pieces were prepared under the same conditions (Table 1).

<2. Pressing and peeling of resin substrate>: The test pieces of Examples 1 to 3 and Comparative Examples 1 to 3 were prepared by removing the solution used in the prepreg treatment before lamination and fully drying. The test piece laminated prepreg (R5670KJ, manufactured by Panasonic) was heat-pressed in a vacuum with a vacuum high-pressure press under the conditions of 2.9 MPa, 210°C, and 120 minutes of pressing to obtain a laminated body sample. The cross section of the obtained laminated body sample was obtained by FIB (focused ion beam) processing under the conditions of 30 kV acceleration voltage and 4 nA probe current. The cross section was observed using a focused ion beam scanning electron microscope (Auriga, manufactured by Carl Zeiss) at a magnification of 30,000 times and a resolution of 1024×768 to obtain a SEM cross-sectional image (Figure 3). For the laminated sample, the copper component was peeled off from the resin substrate based on the 90-degree peeling test (Japanese Industrial Standard (JIS) C5016). The image of the test piece after peeling and the peeling strength (kgf/cm) are shown in Figure 2, and the SEM cross-sectional images of the laminated sample before and after peeling are shown in Figure 6. In Figure 6, in relation to Comparative Example 3, a Pt deposition layer for protecting the processed surface is deposited on the resin substrate side, and an image is obtained. As shown in Figures 2 and 6, only in the embodiment, the needle-shaped crystalline copper oxide or the needle-shaped protrusions from the needle-shaped crystalline copper oxide with almost the same thickness and nickel-plated are almost separated from the copper foil and transferred to the resin substrate side. In addition, the peeling strength of the embodiment is also very small compared with the comparative example.

<3. Binarization of SEM cross-sectional images after hot pressing>: The SEM cross-sectional images of the obtained laminated sample (configured so that the needle-shaped protrusions face upward; image size = 3.78μm×2.61μm; resolution 1024×768) were binarized using the image analysis software WinROOF2018 (Mitani Shoji Co., Ltd., ver4.5.5) through the following steps.

<Operation>

1) Selection range (rectangular ROI): The area enclosed by the straight line parallel to the integrated layer passing through the apex of the void closest to the copper side and the straight line parallel to the integrated layer passing through the apex of the highest convexity formed on the copper surface is used as the measurement range.

2) Image processing → Emphasis (brightness ±0, contrast +20): To facilitate image processing, adjust the contrast.

3) Image processing → Emphasis → Inversion: In order to select gaps in the binarization process, inversion processing is performed to swap the bright and dark parts of the image.

4) Automatic binarization (discriminant analysis method): Automatic binarization is performed to select the area surrounded by copper and copper oxide and the area surrounded by copper oxide. The threshold is determined by the discriminant analysis method.

5) Noise removal: Noise is considered to be 1 pixel in length, and noise is removed if the area is less than ^15nm2 .

6) Calculate the gap distance: When the image is arranged so that the convex part is facing upward, the upper left corner of the image is used as the origin, the downward direction in the image is used as the X axis, and the rightward direction is used as the Y axis. The distance between the two points is calculated by taking the area selected by automatic binarization where X=maximum and Y=minimum as the starting point and the distance between it and the area at the closest distance in the Y axis direction. When calculating the distance between two points, define each selected area as a gap.

7) Determination of void size: The maximum horizontal chord length of the void is calculated and used as the size of each void. The SEM cross-sectional images of each multilayer sample after inversion binarization are shown in Figure 4. In addition, the results of calculating the voids and the average distance between voids are shown in Figure 5.

Compared with Examples 2 and 3, which only count the area surrounded by copper oxide (i.e., the gaps between the copper oxide layer and the unevenness) as gaps, the embodiment counts the area surrounded by copper oxide and the area surrounded by copper and copper oxide (i.e., the area existing at the interface between the layer containing copper oxide and the copper foil) as gaps. Therefore, the number of gaps calculated in the embodiment is larger and the distance between the gaps is shorter. In addition, in the embodiment, the proportion of gaps with a distance of less than 50nm accounts for more than 40% of the total.

<4. Measurement of Ra and surface area of composite copper foil before and after hot pressing>

(1) Methods

For the composite copper foil test pieces of Examples 1 to 3 and Comparative Examples 1 and 2, the surface area before and after hot pressing and peeling was calculated using a conjugate scanning electron microscope OPTELICS H1200 (manufactured by Lasertec Co., Ltd.). Measurement conditions: mode is conjugate mode, scanning area is 100μm×100μm, light source is blue light, and cut-off value is 1/5. Objective lens x100, eyepiece x14, digital zoom x1, Z distance is set to 10nm, data from 3 positions are obtained, and the surface area is the average value of the 3 positions.

(2) Results

As shown in Table 2, before hot pressing and after stripping, Ra and surface area decreased in the example, while they increased in the comparative example. This means that all or part of the protrusions of the composite copper component in the example were transferred to the resin side, while in the comparative example, part of the resin was transferred to the composite copper component.

According to the present invention, a novel composite copper component can be provided. The composite copper component is suitable for use in the SAP method or the MSAP method (FIG. 7). In order to allow the plating liquid to penetrate into the bottom of the concave portion, the shape of the concave portion needs to be large to a certain extent, which is not suitable for forming fine wiring (Japanese Patent Publication No. 2017-034216). However, when the composite copper foil of the present invention is used, the layer containing copper oxide that forms the concave and convex portions will transfer itself, so there is no need to allow the plating liquid to penetrate into the bottom of the concave portion. The (pattern) copper plating can be performed on the layer containing the transferred copper oxide and having no concave and convex portions. Even if the concave portion on the surface of the original composite copper component is elongated in shape, the possibility of generating gaps between the resin substrate and the (pattern) copper plating layer is low, and it is suitable for forming fine wiring. Furthermore, since copper plating is performed on the layer containing copper oxide, copper plating has a high bonding affinity for the layer containing copper oxide, and the peeling strength between the resin substrate and the (patterned) copper-plated layer is ensured by the bonding of the layer containing copper oxide bonded to the copper-plated layer. It is known that the peeling strength cannot be stabilized even when an oxidized metal is used as a peeling layer to produce a carrier foil (International Publication No. 2010/027052). However, by forming voids in the layer containing copper oxide, the composite copper component of the present invention can be directly used as a copper component to which a carrier metal foil is attached, or used to produce the copper component. Even if the carrier foil is attached, it is too thin and cannot withstand the hot pressing step to the resin substrate from the perspective of strength. For example, the composite copper foil of Example 2 or 3 shows that the copper foil part acts as a carrier, which can transfer the layer containing copper oxide and the nickel plating layer, so the conductive nickel with a thickness of only tens of nanometers can be hot pressed to the resin substrate. The layer containing copper oxide is also transferred, so the physical strength of the nickel layer is enhanced by the presence of the layer containing copper oxide transferred at the same time. On the other hand, the conductivity of the layer containing copper oxide is extremely low, so it does not conduct electricity, and there is almost no transmission loss caused by the presence of the layer containing copper oxide.

Claims (24)

A composite copper component is provided, wherein a layer containing copper oxide is formed on at least a portion of a surface of the copper component, the layer containing copper oxide has a plurality of voids, at least a portion of the voids are present at an interface between the layer containing copper oxide and the surface of the copper component, the surface of the layer containing copper oxide of the composite copper component is heat-pressed to a resin substrate under prescribed conditions to form a laminate, a scanning electron microscope cross-section image of the laminate is obtained, and when the image is binarized, when measured in a direction parallel to the laminate surface, the number of the voids detected in any 3.8 μm is 30 or more. The composite copper member of claim 1, wherein the peel strength between the layer containing copper oxide and the surface of the copper member is greater than or equal to 0.001 kgf/cm and less than or equal to 0.30 kgf/cm. A composite copper member as claimed in claim 1 or 2, wherein a scanning electron microscope cross-sectional image is obtained, the image is binarized, and when measured in a direction parallel to the layer containing copper oxide, the number of voids detected in any 3.8 μm is greater than 30. A composite copper member as claimed in claim 1 or 2, wherein in the binary cross-sectional image, an average distance between the gaps is less than 100 nm. A composite copper component as claimed in claim 1 or 2, wherein in the binary cross-sectional image, the distance between the gaps being less than 50 nm accounts for more than 40% of the total gaps. A composite copper structure as claimed in claim 1 or 2, wherein the resin substrate contains at least one insulating resin selected from the group consisting of polyphenylene ether, epoxy resin, polyoxyxylene, polybenzoxazole, liquid crystal polymer, triphenyl phosphite, fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, dimaleimide resin, low-capacitance polyimide and cyanate resin. The composite copper structure of claim 1 or 2, wherein the specified conditions of the hot pressing are within the range of a temperature of 50°C to 400°C, a pressure of 0 to 20 MPa, and a time of 1 minute to 5 hours. The composite copper member of claim 1 or 2, wherein the Ra of the surface on which the layer containing copper oxide is formed is greater than 0.03 μm, and the ratio of the Ra of the surface of the copper member peeled off from the resin substrate to the Ra is less than 100%. The composite copper member of claim 1 or 2, wherein the ratio of the surface area of the copper member peeled off from the resin substrate after hot pressing to the surface area of the surface on which the layer containing copper oxide is formed is less than 100%. A composite copper member as claimed in claim 1 or 2, wherein the layer comprising copper oxide comprises a metal other than copper. A composite copper component as claimed in claim 10, wherein the metal other than copper is nickel. A composite copper member as claimed in claim 1 or 2, wherein the layer comprising copper oxide comprises a copper plated layer. A carrier metal foil comprises the composite copper member as claimed in claim 10, wherein the layer comprising copper oxide is used as a metal foil, and the copper member is used as a carrier relative to the metal foil. A laminated body comprises a resin substrate laminated on at least a portion of the surface of the layer containing copper oxide of the composite copper member as claimed in claim 1 or 2. A laminate as claimed in claim 14, wherein the resin substrate contains at least one insulating resin selected from the group consisting of polyphenylene ether, epoxy resin, polyoxyxylene, polybenzoxazole, liquid crystal polymer, triphenyl phosphite, fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, dimaleimide resin, low-capacitance polyimide and cyanate resin. The composite copper component of claim 1 or 2 is used for manufacturing a printed wiring board. The composite copper structure of claim 16 is used to manufacture a printed wiring board using a semi-additive process or an M-SAP process. A method for manufacturing a printed wiring board using a composite copper component as claimed in claim 1 or 2, comprising: 1) a step of hot pressing a resin substrate on the layer containing copper oxide of the composite copper component under specified conditions; 2) a step of peeling the copper component from the resin substrate under specified conditions to obtain a resin substrate having a part or all of the metal forming the layer containing copper oxide; and 3) a step of copper plating the surface of the resin substrate having a part or all of the metal forming the layer containing copper oxide. A method for manufacturing a resin substrate having a metal, comprising: 1) a step of hot pressing a resin substrate on the layer containing copper oxide of a composite copper component as claimed in claim 1 or 2 under specified conditions; and 2) a step of peeling the copper component from the resin substrate under specified conditions to obtain a resin substrate having a part or all of the metal forming the layer containing copper oxide. A method for manufacturing a composite copper component is a method for manufacturing a composite copper component as claimed in claim 1 or 2, comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; and 2) a step of forming the layer comprising copper oxide by oxidizing the partially coated surface. A method for manufacturing a composite copper component is a method for manufacturing a composite copper component as claimed in claim 1 or 2, comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface; and 3) a step of treating the surface of the formed layer containing copper oxide with a modifier, wherein the modifier comprises a compound selected from the group consisting of nickel chloride, zinc chloride, iron chloride, chromium chloride, ammonium citrate, ammonium chloride, potassium chloride, ammonium sulfate and nickel ammonium sulfate. A method for manufacturing a composite copper component is a method for manufacturing a composite copper component as claimed in claim 10, comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface; and 3) a step of forming a layer containing a metal other than copper on the oxidized surface. A method for manufacturing a composite copper component is a method for manufacturing a composite copper component as claimed in claim 10, comprising: 1) a step of oxidizing the surface of the copper component; 2) a step of treating the oxidized surface with a modifier; and 3) a step of forming a layer containing a metal other than copper on the surface treated with the modifier, wherein the modifier contains a compound selected from the group consisting of nickel chloride, zinc chloride, iron chloride, chromium chloride, ammonium citrate, ammonium chloride, potassium chloride, ammonium sulfate and nickel ammonium sulfate. A method for manufacturing a composite copper component is a method for manufacturing a composite copper component as claimed in claim 10, comprising: 1) a step of partially coating the surface of the copper component with a silane coupling agent; 2) a step of oxidizing the partially coated surface; 3) a step of treating the oxidized surface with a modifier, and 4) a step of forming a layer containing a metal other than copper on the surface treated with the modifier, wherein the modifier contains a compound selected from the group consisting of nickel chloride, zinc chloride, iron chloride, chromium chloride, ammonium citrate, ammonium chloride, potassium chloride, ammonium sulfate and nickelammonium sulfate.