Copper foil with carrier, copper clad laminate and printed wiring board

Abstract

This copper foil is provided with a carrier, which even after high-temperature pressing at above 350°C, can be easily peeled off. This copper foil with a carrier comprises the carrier, an interlayer, and a copper foil in this order, wherein the interlayer comprises a Cr phase, an Ni-P phase, and an Mo-Fe-Ni phase. In the interlayer-side surface of the carrier, the proportion of a surface covered with the Mo-Fe-Ni phase is 61.00-96.00%. In the interlayer, the ratio of the deposited Ni amount to the deposited Mo amount, Ni / Mo, is 2.00 or greater. In the interlayer, the Fe content which is the proportion of the deposited Fe amount to the sum of the deposited Mo amount, the deposited Ni amount, and the deposited Fe amount is 8.90% or less.

Description

[Technical Field]

[0001] The present disclosure relates to a carrier-attached copper foil, a copper-clad laminate, and a printed wiring board. [Background technology]

[0002] Carrier-attached copper foil is widely used as a material for manufacturing printed wiring boards. Carrier-attached copper foil typically comprises a carrier, an intermediate layer (e.g., a release layer), and a copper foil, in this order, and is laminated with an insulating resin substrate by hot pressing to form a copper-clad laminate, which is used in manufacturing printed wiring boards.

[0003] In recent years, there has been a demand for printed wiring boards suitable for high-frequency applications such as 5G and millimeter waves. For such high-frequency printed wiring boards, reduced transmission loss is desirable to enable the transmission of high-frequency signals without degrading their quality. Therefore, to reduce the dielectric loss caused by insulating resin substrates, high-frequency printed wiring boards use low-dielectric-constant thermoplastic resin substrates, such as polytetrafluoroethylene (PTFE) and liquid crystal polymer (LCP). These thermoplastic resin substrates require processing temperatures exceeding 350°C. However, with conventional carrier-attached copper foils, the peel strength increases with increasing processing temperature. At these processing temperatures, the peel strength between the substrate and carrier increases significantly, leading to problems such as the inability to peel the carrier.

[0004] To address these issues, several carrier-attached copper foils with improved high-temperature resistance have been proposed. For example, Patent Document 1 (WO 2009 / 084839) discloses a carrier-attached copper foil comprising a carrier, a release layer, and a copper foil, in which the release layer contains a first metal with releasability, such as Mo or W, and a second and third metal, such as Fe, Co, or Ni, that facilitates coating of the first metal. With such carrier-attached copper foil, swelling of the release layer does not occur even at high temperatures during the manufacturing process of printed wiring boards, making it possible to easily peel off the carrier. Furthermore, Patent Document 2 (WO 2002 / 024444) discloses a carrier-attached copper foil having a release layer, a diffusion barrier layer, and an electroplated copper layer on the carrier surface in this order, in which a chromium layer or a chromium hydrate oxide layer is used as the release layer, and a specific metal layer or metal oxide layer that easily absorbs light of the wavelength oscillated by a CO gas laser is used as the diffusion barrier layer. Such a carrier-attached copper foil makes it possible to produce a copper-clad laminate even when using a resin substrate that is produced by casting or pressing at high temperatures. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] WO2009 / 084839 [Patent Document 2] WO2002 / 024444 Summary of the Invention

[0006] However, conventional carrier-attached copper foils such as those disclosed in Patent Documents 1 and 2 are still insufficient in terms of high-temperature resistance, and further improvement is desired.

[0007] The present inventors have now discovered that in a carrier-attached copper foil, by interposing an intermediate layer having a Cr phase, a Ni-P phase, and a Mo-Fe-Ni phase between the carrier and the copper foil, and by controlling the Ni / Mo ratio and Fe content of the intermediate layer, as well as the coverage rate of the carrier by the Mo-Fe-Ni phase, within respective predetermined ranges, the carrier can be easily peeled off even after high-temperature pressing at above 350°C.

[0008] Therefore, an object of the present invention is to provide a copper foil with a carrier from which the carrier can be easily peeled off even after high-temperature pressing at over 350°C.

[0009] According to the present disclosure, the following aspects are provided. [Aspect 1] A carrier-attached copper foil having a carrier, an intermediate layer, and a copper foil in this order, the intermediate layer has a Cr phase, a Ni-P phase, and a Mo-Fe-Ni phase, a ratio of the surface of the carrier on the intermediate layer side that is covered with the Mo-Fe-Ni phase is 61.00% or more and 96.00% or less, the intermediate layer has a Ni / Mo ratio, which is a ratio of Ni deposition amount to Mo deposition amount, of 2.00 or more; The carrier-attached copper foil has an Fe content, which is the ratio of the Fe deposition amount to the total amount of the Mo deposition amount, the Ni deposition amount, and the Fe deposition amount in the intermediate layer, of 8.90% or less. [Aspect 2] 2. The copper foil with a carrier according to claim 1, wherein the intermediate layer further comprises an additional Ni—P phase on the Mo—Fe—Ni phase. [Aspect 3] 3. The copper foil with a carrier according to claim 1, wherein the proportion of the surface of the carrier on the intermediate layer side that is covered with the Mo—Fe—Ni phase is 65.00% or more and 96.00% or less. [Aspect 4] A copper foil with a carrier according to aspect 3, wherein the proportion of the surface of the carrier on the intermediate layer side that is covered with the Mo—Fe—Ni phase is 75.00% or more and 96.00% or less. [Aspect 5] 5. The carrier-attached copper foil according to any one of aspects 1 to 4, wherein the Ni / Mo ratio is 3.00 or more and 5.00 or less. [Aspect 6] 6. The copper foil with a carrier according to embodiment 5, wherein the Ni / Mo ratio is 3.50 or more and 5.00 or less. [Aspect 7] 7. The carrier-attached copper foil according to any one of aspects 1 to 6, wherein the Fe content is 1.80% or more and 7.00% or less. [Aspect 8] 8. The carrier-attached copper foil according to claim 7, wherein the Fe content is 1.80% or more and 5.00% or less. [Aspect 9] The carrier-attached copper foil according to any one of aspects 1 to 8, further comprising, on the copper foil, at least one layer selected from the group consisting of a roughening layer composed of a plurality of roughening particles, a rust prevention layer, and a silane coupling agent layer. [Aspect 10] A copper-clad laminate comprising the carrier-attached copper foil according to any one of the first to ninth embodiments. [Aspect 11] A printed wiring board comprising the carrier-attached copper foil according to any one of the first to ninth embodiments. [Aspect 12] A method for producing a printed wiring board, characterized in that a printed wiring board is produced using the carrier-attached copper foil according to any one of aspects 1 to 9. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view showing one embodiment of a carrier-attached copper foil of the present invention. [Figure 2] 2 is an enlarged view of the dashed line portion shown in FIG. 1, illustrating one embodiment of the Cr phase, Ni—P phase, Mo—Fe—Ni phase, and additional Ni—P phase contained in the intermediate layer. [Figure 3] 10 is a graph in which the atomic concentration ratio of Cr to Cu, the atomic concentration ratio of P to Cu, and the ratio of the total atomic concentration of Mo, Fe, and Ni to the atomic concentration of Cu, obtained from the XPS depth profile acquired in Example 7, are plotted against the depth from the peeled surface. [Figure 4] 10 is an SEM image of the intermediate layer side surface of the carrier after binarization obtained in Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0011] definition The following are definitions of terms or parameters used to define the present invention.

[0012] In this specification, the term "Cr phase" refers to a region where the atomic concentration ratio of Cr to Cu is 0.006 or more based on the atomic concentration distributions of P, Cr, Fe, Ni, Cu, and Mo obtained from an XPS depth profile of a depth region including the intermediate layer of a carrier-attached copper foil. The term "Ni-P phase" refers to a region where the atomic concentration ratio of P to Cu is 0.01 or more based on the atomic concentration distributions of P, Cr, Fe, Ni, Cu, and Mo obtained from the XPS depth profile. The term "Mo-Fe-Ni phase" refers to a region where the ratio of the total atomic concentration of Mo, Fe, and Ni to the atomic concentration of Cu is 0.2 or more based on the atomic concentration distributions of P, Cr, Fe, Ni, Cu, and Mo obtained from the XPS depth profile. In the analysis of the carrier-attached copper foil of the present invention by XPS, an XPS depth profile of a depth region including the intermediate layer is obtained using an X-ray source with a predetermined beam diameter (e.g., 200 μmφ), so that not only the elements constituting the intermediate layer but also Cu originating from the copper foil or carrier are inevitably observed. Therefore, each of the above-mentioned phases is identified by its atomic concentration ratio relative to Cu. The XPS depth profile of the depth region including the intermediate layer can be obtained by performing elemental analysis by XPS while digging in the depth direction (toward the surface opposite the peeled surface) on the carrier-side peeled surface and the copper foil-side peeled surface after the carrier has been peeled off using ion beam sputtering with an ion gun. Preferred measurement conditions for XPS are shown in the Examples below.

[0013] In this specification, the "Ni / Mo ratio" refers to the ratio of the Ni coating weight to the Mo coating weight in the intermediate layer (=Ni coating weight / Mo coating weight). Furthermore, the "Fe content" refers to the proportion of the Fe coating weight in the total of the Mo coating weight, Ni coating weight, and Fe coating weight in the intermediate layer (=100×Fe coating weight / (Mo coating weight+Ni coating weight+Fe coating weight)). The Mo coating weight, Ni coating weight, and Fe coating weight are the weights of Mo, Ni, and Fe present per unit area in the intermediate layer, respectively. The Mo coating weight, Ni coating weight, and Fe coating weight can be calculated by dissolving a predetermined area of ​​the intermediate layer in acid and analyzing the Mo concentration, Ni concentration, and Fe concentration in the resulting solution by ICP atomic emission spectrometry.

[0014] In this specification, the "coating ratio of the carrier with the Mo-Fe-Ni phase" means the ratio of the surface of the carrier on the intermediate layer side that is coated with the Mo-Fe-Ni phase. The coating ratio of the carrier with the Mo-Fe-Ni phase can be measured according to the procedure shown in the examples below.

[0015] In this specification, the "electrode surface" of the electrolytic copper foil refers to the surface that was in contact with the cathode during the preparation of the electrolytic copper foil.

[0016] Copper foil with carrier One embodiment of the carrier-attached copper foil of the present invention is shown in Figures 1 and 2. The carrier-attached copper foil 10 shown in Figure 1 comprises a carrier 12, an intermediate layer 14, and a copper foil 16, in this order. As shown in Figure 2, the intermediate layer 14 has a Cr phase 14a, a Ni-P phase 14b, and a Mo-Fe-Ni phase 14c. In the intermediate layer 14, the Ni / Mo ratio, which is the ratio of the Ni coating weight to the Mo coating weight, is 2.00 or more. In the intermediate layer 14, the Fe content, which is the proportion of the Fe coating weight to the total of the Mo coating weight, Ni coating weight, and Fe coating weight, is 8.90% or less. In the carrier-attached copper foil 10, the proportion of the surface of the carrier 12 facing the intermediate layer 14 that is covered with the Mo-Fe-Ni phase 14c is 61.00% or more and 96.00% or less. In this way, in the carrier-added copper foil 10, the intermediate layer 14 having the Cr phase 14a, Ni-P phase 14b, and Mo-Fe-Ni phase 14c is interposed between the carrier 12 and the copper foil 16, and the Ni / Mo ratio and Fe content of the intermediate layer 14, as well as the coverage ratio of the carrier by the Mo-Fe-Ni phase 14c, are controlled within predetermined ranges, so that the carrier 12 can be easily peeled off even after high-temperature pressing exceeding 350° C. A specific index of the peel strength of the carrier 12, measured under the conditions shown in the examples described later, is preferably 90.0 gf / cm or less, and more preferably 50.0 gf / cm or less.

[0017] The intermediate layer 14 weakens the peel strength of the carrier 12, ensures stability of that strength, and further functions to suppress interdiffusion that may occur between the carrier 12 and the copper foil 16 during high-temperature press forming. The Cr phase 14a in the intermediate layer 14 contains Cr and typically exists to form an interface with the carrier 12. That is, when the carrier 12 is peeled off after the carrier-attached copper foil 10 and an insulating resin substrate are bonded together, the Cr phase 14a typically serves as the peel surface between the carrier 12 and the copper foil 16. The Ni-P phase 14b in the intermediate layer 14 contains Ni and P and contributes to improving the plating properties of the Mo-Fe-Ni phase 14c and the like. Typically, the Ni-P phase 14b is particulate and present scattered on the carrier 12. The Mo-Fe-Ni phase 14c in the intermediate layer 14 contains Mo, Fe, and Ni and contributes to improving the high-temperature resistance of the carrier-attached copper foil 10. Typically, the Mo-Fe-Ni phase 14c is particulate and exists so as to embed the particulate Ni-P phase 14b. That is, the Mo-Fe-Ni phase 14c typically exists so as to grow grains starting from the Ni-P phase 14b. From the viewpoint of preventing surface oxidation of the Mo-Fe-Ni phase 14c and the like, the intermediate layer 14 preferably further includes an additional Ni-P phase 14d on the Mo-Fe-Ni phase 14c. Typically, the additional Ni-P phase 14d exists so as to cover the outer surface of the particulate Mo-Fe-Ni phase 14c. The thickness of the intermediate layer 14 is typically 50 nm to 500 nm, and preferably 100 nm to 350 nm.

[0018] The Ni / Mo ratio in the intermediate layer 14 is 2.00 or more, preferably 3.00 to 5.00, more preferably 3.50 to 5.00, and even more preferably 3.50 to 4.50. The Fe content in the intermediate layer 14 is 8.90% or less, preferably 1.80% to 7.00%, more preferably 1.80% to 5.00%, and even more preferably 1.80% to 4.50%. Within these ranges, high-temperature resistance can be effectively improved.

[0019] In the carrier-added copper foil 10, the carrier coverage ratio of the Mo-Fe-Ni phase 14c is 61.00% or more and 96.00% or less, preferably 65.00% or more and 96.00% or less, more preferably 75.00% or more and 96.00% or less, and even more preferably 75.00% or more and 90.00% or less. Within such ranges, the Mo-Fe-Ni phase 14c can effectively improve high-temperature resistance. Note that, when the intermediate layer 14 has an additional Ni-P phase 14d, the above-mentioned carrier coverage ratio value means a value obtained by measuring and analyzing the carrier 12 after the additional Ni-P phase 14d is formed.

[0020] The carrier 12 is a support for supporting the copper foil 16 to improve its handling, and a typical carrier includes a copper layer. Examples of such carriers include copper foil, resin films or glass whose surfaces are coated with a metal such as copper, and copper foil is preferred. The copper foil may be either rolled copper foil or electrolytic copper foil. The thickness of the carrier is typically 250 μm or less, preferably 9 μm to 200 μm, and more preferably 9 μm to 150 μm.

[0021] The copper foil 16 may have any known structure used in carrier-attached copper foils, but is preferably an electrolytic copper foil. The thickness of the copper foil 16 is typically 18 μm or less, preferably 0.1 μm or more and 7.0 μm or less, and more preferably 1.0 μm or more and 3.0 μm or less.

[0022] If desired, the surface of the copper foil 16 may be roughened to form a roughened layer. Providing a roughened layer on the copper foil 16 can improve adhesion with a resin layer during the manufacture of a copper-clad laminate or printed wiring board. As shown in FIG. 1 , this roughened layer comprises a plurality of roughened particles 18, each of which is preferably composed of metal particles, more preferably copper particles. The copper particles may be composed of metallic copper or a copper alloy. The roughening treatment for forming a roughened surface can be preferably carried out by forming roughened particles of a metal or alloy on the copper foil 16. For example, the roughening treatment is preferably carried out according to a plating method involving at least two plating steps, including a burnt plating step in which fine metal particles are deposited and attached to the metal foil, and a cover plating step in which the fine metal particles are prevented from falling off.

[0023] If desired, the surface of the copper foil 16 may be subjected to a rust-proofing treatment to form a rust-proofing layer. The rust-proofing treatment preferably includes a zinc plating treatment. The zinc plating treatment may be either a zinc plating treatment or a zinc alloy plating treatment, with a zinc-nickel alloy plating treatment being particularly preferred. The zinc-nickel alloy plating treatment may be a plating treatment containing at least Ni and Zn, and may further contain other elements such as Sn, Cr, and Co. The Ni / Zn deposition ratio in the zinc-nickel alloy plating is preferably 1.2 to 10, more preferably 2 to 7, and even more preferably 2.7 to 4, by mass. The rust-proofing treatment preferably further includes a chromate treatment, which is preferably performed on the zinc-containing plating surface after the zinc plating treatment. This further improves rust resistance. A particularly preferred rust-proofing treatment is a combination of a zinc-nickel alloy plating treatment followed by a chromate treatment.

[0024] If desired, the surface of the copper foil 16 may be treated with a silane coupling agent to form a silane coupling agent layer, which can improve moisture resistance, chemical resistance, and adhesion to adhesives, etc. The silane coupling agent layer can be formed by applying an appropriately diluted silane coupling agent and drying it. Examples of the silane coupling agent include epoxy-functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane, amino-functional silane coupling agents such as 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane, mercapto-functional silane coupling agents such as 3-mercaptopropyltrimethoxysilane, olefin-functional silane coupling agents such as vinyltrimethoxysilane and vinylphenyltrimethoxysilane, acrylic-functional silane coupling agents such as 3-methacryloxypropyltrimethoxysilane, imidazole-functional silane coupling agents such as imidazole silane, and triazine-functional silane coupling agents such as triazine silane.

[0025] Therefore, the carrier-attached copper foil 10 preferably further comprises at least one layer selected from the group consisting of a roughened layer composed of a plurality of roughening particles 18, a rust-proofing layer, and a silane coupling agent layer on the copper foil 16. For example, when the carrier-attached copper foil 10 further comprises a roughened layer, a rust-proofing layer, and a silane coupling agent layer, the order of these layers is not particularly limited, but it is preferable that the roughened layer, the rust-proofing layer, and the silane coupling agent layer are laminated on the copper foil 16 in this order.

[0026] Manufacturing method of carrier-attached copper foil The carrier-attached copper foil 10 of the present invention can be produced by (1) preparing a carrier 12, (2) forming an intermediate layer 14 on the carrier 12, and (3) forming a copper foil 16 on the intermediate layer 14. An example of a preferred method for producing the carrier-attached copper foil 10 of the present invention will be described below.

[0027] (1) Preparing the carrier First, a carrier 12 is prepared as a support. A typical carrier 12 includes a copper layer. As described above, examples of such a carrier 12 include copper foil, a resin film or glass whose surface is coated with a metal such as copper, and the like, and copper foil is preferred.

[0028] When an electrolytic copper foil is used as the carrier 12, electrolytic foil formation may be performed using a sulfuric acid-based copper electrolyte under known conditions, and is not particularly limited. From the viewpoint of producing an electrolytic copper foil with a smooth surface, the electrolyte may contain additives such as sulfonates of active sulfur compounds and quaternary ammonium salt polymers having a cyclic structure. Examples of sulfonates of active sulfur compounds used as additives include 3-mercapto-1-propanesulfonate and bis(3-sulfopropyl)disulfide, and examples of quaternary ammonium salt polymers having a cyclic structure include diallyldimethylammonium chloride polymers.

[0029] (2) Formation of the middle class An intermediate layer 14 is formed on the carrier 12. The intermediate layer 14 is preferably formed by performing various plating treatments on the surface of the carrier 12 to form a Cr phase 14a, a Ni-P phase 14b, and a Mo-Fe-Ni phase 14c in this order, and more preferably by further forming an additional Ni-P phase 14d after the formation of the Mo-Fe-Ni phase 14c.

[0030] The Cr phase 14a is formed using a solution having a Cr concentration of 0.5 g / L or more and 5.0 g / L or less (more preferably 0.5 g / L or more and 2.0 g / L or less, and even more preferably 0.5 g / L or more and 1.0 g / L or less) and a pH of 7 or more and 12 or less, at a solution temperature of 5° C. or more and 50° C. or less, and at a current density of 0.5 A / dm 2 More than 20.0A / dm2 Less than (preferably 0.5A / dm 2 More than 10.0A / dm 2 Less than or equal to 0.5A / dm, more preferably 0.5A / dm 2 More than 5.0A / dm 2 It is preferable to carry out the plating treatment under the conditions of a nitrogen atmosphere of 2.0 As or more and a quantity of electricity of 50.0 As or less (more preferably, 2.0 As or more and 30.0 As or less, and even more preferably, 2.0 As or more and 20.0 As or less).

[0031] The Ni-P phase 14b is formed using a solution having a Ni concentration of 10.0 g / L or more and 50.0 g / L or less (more preferably 10.0 g / L or more and 30.0 g / L or less, and even more preferably 10.0 g / L or more and 20.0 g / L or less), a P concentration of 5.0 g / L or more and 30.0 g / L or less (more preferably 5.0 g / L or more and 20.0 g / L or less, and even more preferably 5.0 g / L or more and 15.0 g / L or less), and a pH of 1 or more and 5 or less, at a solution temperature of 5° C. or more and 50° C. or less, and a current density of 1.0 A / dm 2 More than 20.0A / dm 2 Less than (more preferably 1.0A / dm 2 More than 10.0A / dm 2 Less than 1.0 A / dm, more preferably 1.0 A / dm 2 More than 5.0A / dm 2 It is preferable to carry out the plating treatment under the conditions of a nitrogen atmosphere of 2.0 As or more and a quantity of electricity of 50.0 As or less (more preferably, 2.0 As or more and 30.0 As or less, and even more preferably, 2.0 As or more and 20.0 As or less).

[0032] The formation of the Mo-Fe-Ni phase 14c is achieved when the Mo concentration is 1.0 g / L or more and 50.0 g / L or less (more preferably 1.0 g / L or more and 30.0 g / L or less, and even more preferably 1.0 g / L or more and 15.0 g / L or less), the Fe concentration is 0.5 g / L or more and 30.0 g / L or less (more preferably 0.5 g / L or more and 20.0 g / L or less, and even more preferably 0.5 g / L or more and 10.0 g / L or less), and the Ni concentration is 1.0 g / L or more and 50.0 g / L or less. L or less (more preferably 1.0 g / L or more and 30.0 g / L or less, and even more preferably 1.0 g / L or more and 10.0 g / L or less), a sodium citrate concentration of 100 g / L or more and 500 g / L or less (more preferably 100 g / L or more and 300 g / L or less, and even more preferably 100 g / L or more and 200 g / L or less), a pH of 7 or more and 12 or less, and a solution temperature of 5°C or more and 50°C or less, a current density of 30.0 A / dm 2 More than 70.0A / dm 2 Less than (more preferably 30.0A / dm 2 More than 60.0A / dm 2 Less than or equal to 30.0 A / dm 2 More than 50.0A / dm 2 It is preferable to carry out the plating treatment under the conditions of a saturation voltage of 200 As or more and 1000 As or less (more preferably, a voltage of 200 As or more and 800 As or less, and even more preferably, a voltage of 200 As or more and 650 As or less).

[0033] The additional Ni-P phase 14d is formed using the same solution as the Ni-P phase 14b, at a solution temperature of 5°C to 50°C and a current density of 0.2 A / dm 2 More than 10.0A / dm 2 Less than (more preferably 0.2A / dm 2 More than 5.0A / dm 2 Less than or equal to 0.2 A / dm, more preferably 0.2 A / dm 2 More than 2.0A / dm 2 It is preferable to carry out plating treatment under the conditions of a nitrogen content of more than 0 As and not more than 20.0 As (more preferably, 0.5 As or more and 10.0 As or less, and even more preferably, 1.0 As or more and 5.0 As or less).

[0034] (3) Copper foil formation Copper foil 16 is formed on intermediate layer 14. For example, the copper foil may be formed by a wet film formation method such as electroless copper plating or electrolytic copper plating, a dry film formation method such as sputtering or chemical vapor deposition, or a combination thereof. Preferably, the copper foil is formed by electrolytic copper plating. Electrolytic foil formation of copper foil 16 may be performed using a sulfuric acid-based copper electrolyte under known conditions, and is not particularly limited.

[0035] If desired, the surface of the copper foil 16 may be subjected to a roughening treatment, a rust prevention treatment, and / or a silane coupling agent treatment to form a roughened layer, a rust prevention treatment layer, and / or a silane coupling agent layer made up of a plurality of roughening particles 18. These treatments are as described above.

[0036] Copper-clad laminate The carrier-attached copper foil 10 of the present invention is preferably used to produce a copper-clad laminate for printed wiring boards. That is, according to a preferred embodiment of the present invention, a copper-clad laminate including the carrier-attached copper foil 10 is provided. The copper-clad laminate includes the carrier-attached copper foil 10, which includes a carrier 12, an intermediate layer 14, and a copper foil 16 in this order, and a resin layer provided on the surface of the copper foil 16 of the carrier-attached copper foil 10 (the surface of the copper foil 16 opposite the intermediate layer 14). The preferred embodiments of the carrier-attached copper foil 10 described above also apply to the carrier-attached copper foil included in a copper-clad laminate. The carrier-attached copper foil 10 may be provided on one or both sides of the resin layer. The resin layer contains a resin, preferably an insulating resin. The resin layer is preferably a prepreg and / or a resin sheet. Prepreg is a general term for a composite material in which a substrate such as a synthetic resin plate, a glass plate, a woven glass fabric, a nonwoven glass fabric, or paper is impregnated with a synthetic resin. The resin layer may contain filler particles made of various inorganic particles such as silica and alumina to improve insulation. The thickness of the resin layer is not particularly limited, but is preferably 1 μm or more and 1000 μm or less, more preferably 2 μm or more and 400 μm or less, and even more preferably 3 μm or more and 200 μm or less. The resin layer may be composed of multiple layers. A resin layer such as a prepreg and / or a resin sheet may be provided on the carrier-attached copper foil 10 via a primer resin layer that is applied in advance to the copper foil surface.

[0037] From the viewpoint of providing a copper-clad laminate suitable for high-frequency applications, the resin layer preferably contains a thermoplastic resin, and more preferably, the majority (e.g., 50% by weight or more) or almost all (e.g., 80% by weight or more or 90% by weight or more) of the resin components contained in the resin layer is a thermoplastic resin. Preferred examples of thermoplastic resins include polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), thermoplastic polyimide (PI), polyamideimide (PAI), fluororesin, polyamide (PA), nylon, polyacetal (POM), modified polyphenylene ether (m-PPE), polyethylene terephthalate (PET), glass fiber reinforced polyethylene terephthalate (GF-PET), cycloolefin (COP), and any combination thereof. From the viewpoint of desirable dielectric loss tangent and excellent heat resistance, more preferred examples of thermoplastic resins include polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), thermoplastic polyimide (PI), polyamideimide (PAI), fluororesin, and any combination thereof. From the viewpoint of low dielectric constant, particularly preferred thermoplastic resins are liquid crystal polymer (LCP) and / or fluororesin. Preferred examples of fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkylvinylether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer (ETFE), and any combination thereof.

[0038] printed wiring board The carrier-attached copper foil 10 of the present invention is preferably used to produce a printed wiring board. That is, according to a preferred embodiment of the present invention, a printed wiring board including the carrier-attached copper foil 10, or a method for producing the same, is provided. The printed wiring board according to this embodiment has a layer structure in which a resin layer and a copper layer are laminated in this order. The resin layer is as described above for the copper-clad laminate. In any case, a known layer structure can be adopted for the printed wiring board. Specific examples of printed wiring boards include single-sided or double-sided printed wiring boards in which the copper foil of the present invention is bonded to one or both sides of a prepreg, the laminate is cured, and a circuit is then formed on the laminate, and multilayer printed wiring boards in which these are layered. Other specific examples include flexible printed wiring boards, COFs, TAB tapes, etc. in which a circuit is formed by forming the copper foil of the present invention on a resin film. Further examples include build-up wiring boards in which a resin-coated copper foil is formed by applying the resin layer described above to a copper foil, and the resin layer is then laminated onto the printed wiring board described above as an insulating adhesive layer. The copper foil is then used as all or part of the wiring layer to form a circuit using techniques such as the modified semi-additive process (MSAP) or the subtractive process. Other examples include build-up wiring boards in which the copper foil is removed and a circuit is formed using the semi-additive process (SAP). Direct build-up on wafers is also possible, in which lamination of resin-coated copper foil and circuit formation are alternately repeated on a semiconductor integrated circuit. The carrier-attached copper foil 10 of the present invention can also be advantageously used in manufacturing methods using a coreless build-up process, in which insulating resin layers and conductor layers are alternately laminated without using a core substrate. More advanced examples include antenna elements in which the resin-coated copper foil is laminated onto a substrate to form a circuit; electronic materials for panel displays and window glass in which a pattern is formed by laminating the resin-coated copper foil onto glass or a resin film via an adhesive layer; and electromagnetic wave shielding films in which a conductive adhesive is applied to copper foil. In particular, the printed wiring board of the present invention is suitable for use as a high-frequency substrate in applications such as automobile antennas, mobile phone base station antennas, high-performance servers, and collision prevention radars, which are used in high-frequency bands with signal frequencies of 10 GHz or higher. [Example]

[0039] The present invention will be explained in more detail by the following examples, but the present invention is not limited to the following examples.

[0040] Examples 1-14 A carrier-attached copper foil having a carrier, an intermediate layer, and a copper foil in this order was produced as follows.

[0041] (1) Career preparation The copper electrolyte used was a sulfuric acid acid copper sulfate solution with the composition shown below. The cathode was a titanium electrode with a surface roughness Ra of 0.20 μm, and the anode was a DSA (dimensionally stable anode). The solution temperature was 45°C, and the current density was 55 A / dm 2 The copper foil was electrolyzed at 18 μm thickness to obtain an electrolytic copper foil as a carrier. <Composition of Acidified Copper Sulfate Solution> - Copper concentration: 80g / L - Sulfuric acid concentration: 260g / L - Bis(3-sulfopropyl) disulfide concentration: 30 mg / L - Diallyldimethylammonium chloride polymer concentration: 50 mg / L - Chlorine concentration: 40mg / L

[0042] (2) Formation of the middle class The obtained carrier was immersed in a sulfuric acid aqueous solution with a sulfuric acid concentration of 100 g / L for 60 seconds to perform surface cleaning, and then an intermediate layer was formed on the electrode surface of the carrier. First, for Examples 1 to 13, chromic acid was dissolved in pure water to obtain the Cr concentration shown in Table 1, and a potassium hydroxide aqueous solution was added to adjust the pH to 10. Using this solution, a plating process was performed at a solution temperature of 20°C under the conditions of the current density and electricity amount shown in Table 1 to form a Cr phase. On the other hand, for Example 14, no Cr phase was formed.

[0043] Thereafter, sodium phosphite pentahydrate and nickel sulfate hexahydrate were dissolved in pure water to give the Ni and P concentrations shown in Table 1, and a sulfuric acid solution with a sulfuric acid concentration of 300 g / L was added to adjust the pH to 4.0. This solution was used to perform plating at a solution temperature of 30°C under the conditions of the current density and quantity of electricity shown in Table 1, thereby forming a Ni-P phase. Next, disodium molybdate, nickel sulfate hexahydrate, iron (II) sulfate heptahydrate, and trisodium citrate dihydrate were dissolved in pure water to give the Mo, Fe, Ni, and sodium citrate concentrations shown in Table 1, and 50 mL of ammonia water was added to 1 L of this solution. This solution was used to perform plating at a solution temperature of 30°C under the conditions of the current density and quantity of electricity shown in Table 1, thereby forming a Mo-Fe-Ni phase.

[0044] For Examples 1 to 5 and 7 to 14, an additional Ni-P phase was formed by plating using the same solution as used for forming the Ni-P phase above, at a solution temperature of 30°C, under the conditions of the current density and quantity of electricity shown in Table 1. On the other hand, for Example 6, no additional Ni-P phase was formed.

[0045] (3) Copper foil formation The carrier on which the intermediate layer was formed was immersed in a solution of the composition shown below, and the solution temperature was 45°C, and the current density was 20 A / dm 2 Electroplating was carried out under the conditions above to form a copper foil with a thickness of 3 μm on the intermediate layer, thereby obtaining a copper foil with a carrier. <Solution composition> - Copper concentration: 75g / L - Free sulfuric acid concentration: 150g / L

[0046] (4) Roughening treatment The surface of the carrier-attached copper foil was washed by immersing it in a sulfuric acid aqueous solution with a sulfuric acid concentration of 100 g / L for 30 seconds, and then the copper foil surface of the carrier-attached copper foil was subjected to a two-stage roughening treatment as follows. The first roughening step was carried out in two stages. Specifically, a solution with a copper concentration of 10.5 g / L, a free sulfuric acid concentration of 100 g / L, and a solution temperature of 25°C was used, and the current density was 28 A / dm 2The first electroplating was carried out under the conditions of 112 As and 112 As of electricity, and then the same solution was used to carry out electroplating at a current density of 18 A / dm 2 The second electroplating was carried out under the condition of an electric charge of 72 As. - The second stage roughening treatment was carried out using a solution with a copper concentration of 65 g / L, a free sulfuric acid concentration of 100 g / L, and a solution temperature of 45°C, with a current density of 4.8 A / dm 2 Electroplating was carried out under the conditions of 56 As and 56 As of electricity.

[0047] (5) Rust prevention treatment The copper foil with carrier after the roughening treatment was subjected to a rust prevention treatment consisting of a zinc-nickel alloy plating treatment and a chromate treatment. First, a solution containing 1 g / L of zinc, 2 g / L of nickel, and 80 g / L of potassium pyrophosphate was used, and the solution temperature was 40°C, the current density was 0.5 A / dm 2 The roughened layer and the surface of the carrier were subjected to zinc-nickel alloy plating treatment under the conditions of: Then, an aqueous solution containing 1 g / L of chromic acid was used, at a pH of 12, and a current density of 1 A / dm 2 Under the conditions above, the zinc-nickel alloy plated surface was subjected to chromate treatment.

[0048] (6) Silane coupling agent treatment A 6 g / L aqueous solution of 3-aminopropyltrimethoxysilane was adsorbed onto the copper foil surface of the carrier-attached copper foil, and the water was evaporated using an electric heater to perform the silane coupling agent treatment. At this time, the carrier side was not treated with the silane coupling agent.

[0049] [Table 1]

[0050] evaluation The copper foils with a carrier produced in Examples 1 to 14 were subjected to the following various evaluations.

[0051] (a) Peel strength measurement A PTFE substrate (RO3003 Bondply, manufactured by ROGERS Corporation, 125 μm thick, 1 ply) was prepared as the fluororesin substrate. The obtained carrier-attached copper foil was laminated onto this PTFE substrate so that the surface-treated copper foil side was in contact with the substrate, and pressed using a vacuum press under conditions of 2.4 MPa, 370°C, and 30 minutes to produce a copper-clad laminate. A hard substrate (a 300 μm thick, heat-cured glass epoxy resin substrate) was attached and fixed to the PTFE substrate side of the obtained copper-clad laminate with double-sided tape to obtain a measurement sample. The carrier was then peeled from this measurement sample, and the peel strength (gf / cm) was measured. Peel strength measurements were performed using a desktop precision universal testing machine (Shimadzu Corporation, AGS-50NX) in accordance with JIS C 6481-1996 under the conditions of a peel width of 50 mm, a peel length of 17 mm, and a peel speed of 50 mm / min. This measurement was performed three times for each example, and the average value was used as the measured value. The results are shown in Table 2.

[0052] (b) Measurement of Ni / Mo ratio and Fe content After peeling off the carrier in (a) above, the peeled surface on the carrier side and the peeled surface on the copper foil side were separated by a predetermined area (75 cm 2 ) was dissolved in acid, and the concentrations of Ni, Mo, and Fe in the resulting solution were analyzed using an ICP atomic emission spectrometer (PS3520UVDD, manufactured by Hitachi High-Tech Science Corporation). The weights of Ni, Mo, and Fe per unit area were then calculated and defined as the Ni adhesion weight, Mo adhesion weight, and Fe adhesion weight in the intermediate layer, respectively. From the resulting adhesion weights, the ratio of the Ni adhesion weight to the Mo adhesion weight (= Ni adhesion weight / Mo adhesion weight) was calculated as the Ni / Mo ratio, and the proportion of the Fe adhesion weight to the total of the Mo adhesion weight, Ni adhesion weight, and Fe adhesion weight (= 100 × Fe adhesion weight / (Mo adhesion weight + Ni adhesion weight + Fe adhesion weight)) was calculated as the Fe content. The results are shown in Table 2.

[0053] (c) Acquisition of XPS depth profile After the carrier was peeled off in (a) above, the peeled surface on the carrier side and the peeled surface on the copper foil side were each subjected to ion beam sputtering using an ion gun, and elemental analysis was performed using XPS while drilling in the depth direction (the surface opposite the peeled surface), and an XPS depth profile of the depth region including the intermediate layer was obtained. This elemental analysis was performed using a scanning dual X-ray photoelectron spectrometer (XPS) (PHI Quantes, manufactured by ULVAC-PHI) under the following measurement conditions. (Measurement conditions) - X-ray beam diameter: 200 μmφ - X-ray output: 50W - X-ray type: Monochromated Al Kα rays - Ion gun settings: ion species Ar gas, acceleration voltage 2 kV, irradiation area 3 mm x 3 mm - Sputtering rate: 3.7nm / min - Measurement elements and orbitals: P 2p, Cr 3p, Fe 3p, Ni 2p3, Cu 2p3, Mo 3d

[0054] Based on the atomic concentration distributions of P, Cr, Fe, Ni, Cu, and Mo obtained from the XPS depth profiles, the atomic concentration ratio of Cr to Cu, the atomic concentration ratio of P to Cu, and the ratio of the total atomic concentration of Mo, Fe, and Ni to the atomic concentration of Cu were calculated. As a result, it was confirmed that, for Examples 1 to 13, there was a region (Cr phase 14a) where the atomic concentration ratio of Cr to Cu was 0.006 or more, a region (Ni-P phase 14b) where the atomic concentration ratio of P to Cu was 0.01 or more, and a region (Mo-Fe-Ni phase 14c) where the ratio of the total atomic concentration of Mo, Fe, and Ni to the atomic concentration of Cu was 0.2 or more. For reference, Figure 3 shows a graph in which the atomic concentration ratio of Cr to Cu, the atomic concentration ratio of P to Cu, and the ratio of the total atomic concentration of Mo, Fe, and Ni to the atomic concentration of Cu obtained from the XPS depth profile in the depth region including the intermediate layer of Example 7 are plotted against the depth from the peeled surface. 3 does not contain a P peak corresponding to the additional Ni-P phase 14d, which is believed to be because the additional Ni-P phase 14d thinly covers the particulate Mo-Fe-Ni phase 14c.On the other hand, it was confirmed that in Example 14, there is a region (Ni-P phase) where the atomic concentration ratio of P to Cu is 0.01 or more, and a region (Mo-Fe-Ni phase) where the ratio of the total atomic concentration of Mo, Fe, and Ni to the atomic concentration of Cu is 0.2 or more, but there is no region (Cr phase) where the atomic concentration ratio of Cr to Cu is 0.006 or more.

[0055] (d) Carrier coverage by Mo-Fe-Ni phase A carrier was prepared and an intermediate layer was formed according to (1) and (2) above, but a measurement sample was prepared in which the intermediate layer was exposed without forming a copper foil. Using a Schottky field emission scanning electron microscope (FE-SEM, JEOL Ltd., JSM-7900F), observations were made perpendicular to the surface of the measurement sample where the intermediate layer was exposed, and SEM images were obtained under the following conditions. (SEM image acquisition conditions) - Observation application: PC-SEM Ver7.1.0.2 - Observation conditions: Accelerating voltage 5.0 kV, Tilt 0° - Magnification: 20,000x - Image size: 1280 pixels x 1024 pixels - Image adjustment: In the "Image adjustment" menu, "Brightness" was set to 0 and "Gamma correction" to 1.50. "Contrast" was set by aligning the "L" bar with the left end of the waveform obtained from the histogram and the "R" bar with the first peak when viewed from the right side of the waveform.

[0056] The acquired SEM images were analyzed using image analysis software (LUZEX (version 1.60.8.2) manufactured by Nireco Corporation) as follows. In this image analysis, a 1260 pixel × 940 pixel area (= 25.39 μm ) was analyzed by excluding the imaging information area from the acquired SEM images. 2 The area (1000 x 1000 x 1000) was analyzed. First, the SEM image was subjected to "SIN" in "grayscale image processing" once, and then binarization processing was performed with a threshold of 0 as the lower limit and 165 as the upper limit. For reference, the binarized SEM image obtained in Example 3 is shown in Figure 4. In the binarized SEM image, the area expressed in white was considered to be the Mo-Fe-Ni phase. Next, the binarized SEM image was subjected to the following filter processing steps (1) to (4) in this order. (1) Logical Filter SMOOTH Strength 5 (2) Snowball filter ELIMINATE1 W Strength 3 (3) Logical filter CIRCLE strength 4 (4) Logical filter FILL HOLES

[0057] The above procedure was performed in five different fields of view, and the average of the values ​​calculated as the "area ratio" in the filtered SEM images was taken as the ratio of the surface of the carrier on the intermediate layer side that was covered with the Mo-Fe-Ni phase. The results are shown in Table 2.

[0058] [Table 2]

Claims

1. A carrier-attached copper foil having a carrier, an intermediate layer, and a copper foil in this order, the intermediate layer has a Cr phase, a Ni—P phase, and a Mo—Fe—Ni phase; a ratio of the surface of the carrier on the intermediate layer side that is covered with the Mo—Fe—Ni phase is 61.00% or more and 96.00% or less, the intermediate layer has a Ni / Mo ratio, which is a ratio of a Ni deposition amount to a Mo deposition amount, of 2.00 or more; The carrier-attached copper foil has an Fe content, which is the ratio of the Fe deposition amount to the total amount of the Mo deposition amount, the Ni deposition amount, and the Fe deposition amount in the intermediate layer, of 8.90% or less.

2. 2. The copper foil with a carrier according to claim 1, wherein the intermediate layer further comprises an additional Ni-P phase on the Mo-Fe-Ni phase.

3. 3. The copper foil with a carrier according to claim 1, wherein the ratio of the surface of the carrier on the intermediate layer side that is covered with the Mo—Fe—Ni phase is 65.00% or more and 96.00% or less.

4. 4. The copper foil with a carrier according to claim 3, wherein the ratio of the surface of the carrier on the intermediate layer side that is covered with the Mo-Fe-Ni phase is 75.00% or more and 96.00% or less.

5. The carrier-attached copper foil according to claim 1 or 2, wherein the Ni / Mo ratio is 3.00 or more and 5.00 or less.

6. The carrier-attached copper foil according to claim 5, wherein the Ni / Mo ratio is 3.50 or more and 5.00 or less.

7. The carrier-attached copper foil according to claim 1 or 2, wherein the Fe content is 1.80% or more and 7.00% or less.

8. The carrier-attached copper foil according to claim 7, wherein the Fe content is 1.80% or more and 5.00% or less.

9. 3. The carrier-attached copper foil according to claim 1, further comprising at least one layer selected from the group consisting of a roughening layer composed of a plurality of roughening particles, a rust prevention layer, and a silane coupling agent layer on the copper foil.

10. A copper-clad laminate comprising the carrier-attached copper foil according to claim 1 or 2.

11. A printed wiring board comprising the carrier-attached copper foil according to claim 1 or 2.

12. A method for producing a printed wiring board, comprising producing a printed wiring board using the carrier-attached copper foil according to claim 1 or 2.

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