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

Abstract

Provided is a copper foil with a carrier, whereby the carrier can be easily peeled off even after high-temperature pressing at a temperature exceeding 350 DEG C. This copper foil with a carrier is provided with a carrier, an intermediate layer, and a copper foil in this order, wherein the intermediate layer has a Cr phase, an Ni-P phase, and a Mo-Fe-Ni phase. In the surface of the carrier on the intermediate layer side, the ratio of the surface covered with the Mo-Fe-Ni phase is from 61.00% to 96.00% (inclusive). The Ni / Mo ratio, which is the ratio of the amount of deposited Ni to the amount of deposited Mo in the intermediate layer, is 2.00 or more. The Fe content of the intermediate layer, which is the ratio of the amount of deposited Fe to the total amount of the amount of deposited Mo, the amount of deposited Ni, and the amount of deposited Fe, is 8.90% or less.

Description

Technical Field

[0001] The present disclosure relates to a copper foil with a carrier, a copper-clad laminate, and a printed circuit board. Background Art

[0002] Copper foil with a carrier is widely used as a material for manufacturing printed circuit boards. This type of copper foil typically has a structure consisting of a carrier, an intermediate layer (e.g., a release layer), and copper foil in this order. This is bonded to an insulating resin substrate through hot pressing to create a copper-clad laminate, which is then used in the manufacture of printed circuit boards.

[0003] In recent years, there is a need to find a printed circuit board (PCB) suitable for high-frequency applications such as 5G and millimeter waves. For such a high-frequency printed circuit board, in order to be able to transmit high-frequency signals without degrading the quality, it is desirable to reduce transmission loss. Therefore, in order to reduce the dielectric loss caused by the insulating resin substrate, a thermoplastic resin substrate with a low dielectric constant such as polytetrafluoroethylene (PTFE) and liquid crystal polymer (LCP) is used in a high-frequency printed circuit board. The processing of these thermoplastic resin substrates requires a temperature exceeding 350°C. On the other hand, in the existing copper foil with a carrier, as the processing temperature rises, the peel strength also rises. Therefore, at this processing temperature, there is a significant increase in the peel strength between the substrate and the carrier, and the problem of being unable to peel the carrier.

[0004] To address this issue, several copper foils with carriers have been proposed that achieve improved high-temperature heat resistance. For example, Patent Document 1 (WO2009 / 084839) discloses a copper foil with a carrier comprising a carrier, a release layer, and copper foil. The release layer comprises a first metal with release properties, such as Mo or W, and a second and third metals, such as Fe, Co, and Ni, that facilitate coating of the first metal. This copper foil with a carrier prevents expansion of the release layer even at high temperatures during the manufacturing process of a printed circuit board, allowing the carrier to be easily released. Furthermore, Patent Document 2 (WO2002 / 024444) discloses a copper foil with a carrier comprising a release layer, a diffusion barrier, and an electroplated copper layer in that order on the carrier surface. The release layer comprises a chromium layer or a chromium hydrated oxide layer, and the diffusion barrier comprises a predetermined metal layer or metal oxide layer that readily absorbs light of the wavelength of a CO2 gas laser. This copper foil with a carrier enables the production of copper-clad laminates, even on resin substrates manufactured by casting or pressing at high temperatures.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: WO2009 / 084839

[0008] Patent Document 2: WO2002 / 024444 Summary of the Invention

[0009] However, the conventional copper foils with carriers disclosed in Patent Documents 1 and 2 cannot be said to be sufficient in terms of high-temperature heat resistance, and further improvement is desired.

[0010] The present inventors have discovered that, in a copper foil with a carrier, by sandwiching 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 carrier coverage ratio achieved by the Mo-Fe-Ni phase, within specified ranges, the carrier can be easily peeled off even after high-temperature pressing exceeding 350°C.

[0011] 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 exceeding 350°C.

[0012] According to the present disclosure, the following aspects are provided.

[0013] [Method 1]

[0014] A copper foil with a carrier, which comprises a carrier, an intermediate layer and a copper foil in sequence.

[0015] The intermediate layer has a Cr phase, a Ni-P phase, and a Mo-Fe-Ni phase.

[0016] The ratio of the surface of the carrier on the intermediate layer side covered with the Mo-Fe-Ni phase is 61.00% or more and 96.00% or less,

[0017] The ratio of the Ni deposition amount to the Mo deposition amount in the intermediate layer, i.e., the Ni / Mo ratio, is 2.00 or more.

[0018] The ratio of the Fe deposited amount in the intermediate layer to the total amount of the Mo deposited amount, the Ni deposited amount, and the Fe deposited amount, that is, the Fe content, is 8.90% or less.

[0019] [Method 2]

[0020] The copper foil with carrier according to aspect 1, wherein the intermediate layer further includes an additional Ni—P phase on the Mo—Fe—Ni phase.

[0021] [Method 3]

[0022] The copper foil with carrier according to aspect 1 or 2, wherein a ratio of a surface of the carrier on the intermediate layer side covered with the Mo—Fe—Ni phase is 65.00% or more and 96.00% or less.

[0023] [Method 4]

[0024] The copper foil with carrier according to aspect 3, wherein a ratio of a surface of the carrier on the intermediate layer side covered with the Mo—Fe—Ni phase is 75.00% or more and 96.00% or less.

[0025] [Method 5]

[0026] The copper foil with a carrier according to any one of aspects 1 to 4, wherein the Ni / Mo ratio is 3.00 or more and 5.00 or less.

[0027] [Method 6]

[0028] The copper foil with a carrier according to aspect 5, wherein the Ni / Mo ratio is 3.50 or more and 5.00 or less.

[0029] [Method 7]

[0030] The copper foil with a carrier according to any one of aspects 1 to 6, wherein the Fe content is 1.80% or more and 7.00% or less.

[0031] [Method 8]

[0032] The copper foil with a carrier according to aspect 7, wherein the Fe content is 1.80% or more and 5.00% or less.

[0033] [Method 9]

[0034] The copper foil with a carrier 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 roughened layer formed of a plurality of roughened particles, a rust-proofing layer, and a silane coupling agent layer.

[0035] [Method 10]

[0036] A copper-clad laminate comprising the copper foil with a carrier according to any one of aspects 1 to 9.

[0037] [Method 11]

[0038] A printed wiring board includes the copper foil with a carrier according to any one of aspects 1 to 9.

[0039] [Method 12]

[0040] A method for manufacturing a printed circuit board, characterized in that the printed circuit board is manufactured using the copper foil with a carrier according to any one of Methods 1 to 9. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a schematic cross-sectional view showing one embodiment of the copper foil with a carrier of the present invention.

[0042] Figure 2 yes Figure 1 The enlarged view of the dotted line portion shows one embodiment of the Cr phase, Ni—P phase, Mo—Fe—Ni phase, and additional Ni—P phase included in the intermediate layer.

[0043] Figure 3 This 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 analysis obtained in Example 7 are plotted against the depth from the peeling surface.

[0044] Figure 4 : is a SEM image of the intermediate layer side surface of the carrier obtained in Example 3 after binarization. DETAILED DESCRIPTION

[0045] definition

[0046] Definitions of terms and parameters used to specify the present invention are shown below.

[0047] In this specification, "Cr phase" refers to a region where the atomic concentration ratio of Cr to Cu is 0.006 or greater, based on the atomic concentration distribution of P, Cr, Fe, Ni, Cu, and Mo obtained by XPS depth profiling of a depth region including the intermediate layer of a copper foil with a carrier. Furthermore, "Ni-P phase" refers to a region where the atomic concentration ratio of P to Cu is 0.01 or greater, based on the atomic concentration distribution of P, Cr, Fe, Ni, Cu, and Mo obtained by the XPS depth profiling. Furthermore, "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 greater, based on the atomic concentration distribution of P, Cr, Fe, Ni, Cu, and Mo obtained by the XPS depth profiling. In the analysis of the copper foil with a carrier of the present invention using XPS, an X-ray source having a predetermined beam diameter (e.g., 200 μmφ) is used to obtain the XPS depth profile of the depth region including the intermediate layer. Therefore, not only the elements constituting the intermediate layer but also Cu originating from the copper foil or the carrier are inevitably observed. Therefore, the above-mentioned phases are identified by their atomic concentration ratios relative to Cu. XPS depth profiling of the deep region including the intermediate layer can be obtained by performing elemental analysis by XPS while digging down in the depth direction (the surface opposite to the peeled surface) using ion beam sputtering using an ion gun on the peeled surface of the carrier side and the peeled surface of the copper foil side after the carrier is peeled off. Preferred measurement conditions for XPS are shown in the Examples described below.

[0048] In this specification, the "Ni / Mo ratio" refers to the ratio of the Ni adhesion amount of the intermediate layer to the Mo adhesion amount (=Ni adhesion amount / Mo adhesion amount). In addition, the "Fe content" refers to the ratio of the Fe adhesion amount of the intermediate layer to the total amount of Mo adhesion amount, Ni adhesion amount, and Fe adhesion amount (=100×Fe adhesion amount / (Mo adhesion amount + Ni adhesion amount + Fe adhesion amount)). The Mo adhesion amount, the Ni adhesion amount, and the Fe adhesion amount are the weight of Mo, the weight of Ni, and the weight of Fe per unit area present in the intermediate layer, respectively. The Mo adhesion amount, the Ni adhesion amount, and the Fe adhesion amount can be calculated by dissolving a specified area of ​​the intermediate layer with acid and analyzing the Mo concentration, Ni concentration, and Fe concentration in the resulting solution based on ICP emission spectroscopy.

[0049] In this specification, "support coverage ratio with the Mo-Fe-Ni phase" refers to the ratio of the support surface on the intermediate layer side that is covered with the Mo-Fe-Ni phase. The support coverage ratio with the Mo-Fe-Ni phase can be measured according to the procedure described in the Examples below.

[0050] In this specification, the "electrode surface" of the electrolytic copper foil refers to the surface on the side that comes into contact with the cathode when the electrolytic copper foil is produced.

[0051] Copper foil with carrier

[0052] One embodiment of the copper foil with carrier of the present invention is as follows Figure 1 and 2 shown. Figure 1 The copper foil with carrier 10 shown in FIG. 1 includes a carrier 12, an intermediate layer 14 and a copper foil 16 in this order. Figure 2As shown, the intermediate layer 14 comprises a Cr phase 14a, a Ni-P phase 14b, and a Mo-Fe-Ni phase 14c. The Ni / Mo ratio, which is the ratio of the Ni content to the Mo content in the intermediate layer 14, is 2.00 or greater. Furthermore, the Fe content, which is the ratio of the Fe content in the intermediate layer 14 to the total of the Mo, Ni, and Fe content, is 8.90% or less. Furthermore, in the copper foil with carrier 10, the proportion of the surface of the carrier 12 on the intermediate layer 14 side covered by the Mo-Fe-Ni phase 14c is 61.00% or greater and 96.00% or less. In this manner, in the copper foil with carrier 10, the intermediate layer 14 having the Cr phase 14a, the Ni-P phase 14b, and the Mo-Fe-Ni phase 14c is sandwiched between the carrier 12 and the copper foil 16. Furthermore, the Ni / Mo ratio and Fe content of the intermediate layer 14, as well as the carrier coverage ratio by the Mo-Fe-Ni phase 14c, are controlled within predetermined ranges. This allows the carrier 12 to be easily peeled off even after high-temperature pressing exceeding 350°C. As a specific indicator of the peel strength of the carrier 12, when measured under the conditions described in the Examples below, the peel strength is preferably 90.0 gf / cm or less, and more preferably 50.0 gf / cm or less.

[0053] The intermediate layer 14 is a layer that has the function of weakening the peel strength of the carrier 12, ensuring the stability of this strength, and further suppressing the interdiffusion that may occur between the carrier 12 and the copper foil 16 during press molding at high temperatures. The Cr phase 14a of the intermediate layer 14 contains Cr and typically exists to form an interface with the carrier 12. That is, when the copper foil 10 with a carrier is bonded to the insulating resin substrate and the carrier 12 is peeled off, the carrier 12 and the copper foil 16 are typically separated using the Cr phase 14a as the peeling surface. The Ni-P phase 14b of the intermediate layer 14 contains Ni and P and helps improve the plating properties of the Mo-Fe-Ni phase 14c and the like. Typically, the Ni-P phase 14b is granular and exists dispersed on the carrier 12. The Mo-Fe-Ni phase 14c of the intermediate layer 14 contains Mo, Fe, and Ni and helps improve the high-temperature heat resistance of the copper foil 10 with a carrier. Typically, the Mo-Fe-Ni phase 14c is granular and exists in a manner that embeds the granular Ni-P phase 14b. That is, typically, the Mo-Fe-Ni phase 14c exists in a manner that uses the Ni-P phase 14b as a starting point for grain growth. From the viewpoint of preventing surface oxidation of the Mo-Fe-Ni phase 14c and the like, the intermediate layer 14 preferably also has an additional Ni-P phase 14d on the Mo-Fe-Ni phase 14c. Typically, the additional Ni-P phase 14d exists in a manner that covers the outer surface of the granular Mo-Fe-Ni phase 14c. The thickness of the intermediate layer 14 is typically greater than 50nm and less than 500nm, preferably greater than 100nm and less than 350nm.

[0054] The Ni / Mo ratio of the intermediate layer 14 is 2.00 or higher by mass, preferably 3.00 or higher and 5.00 or lower, more preferably 3.50 or higher and 5.00 or lower, and even more preferably 3.50 or higher and 4.50 or lower. Furthermore, the Fe content of the intermediate layer 14 is 8.90% or lower, preferably 1.80% or higher and 7.00% or lower, more preferably 1.80% or higher and 5.00% or lower, and even more preferably 1.80% or higher and 4.50% or lower. Within this range, high-temperature heat resistance can be effectively improved.

[0055] The carrier coverage ratio of the copper foil 10 with a carrier, achieved by 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 this range, the Mo-Fe-Ni phase 14c can effectively improve high-temperature heat resistance. It should be noted that when the intermediate layer 14 has an additional Ni-P phase 14d, the numerical value of the carrier coverage ratio is the value obtained by measuring and analyzing the carrier 12 after the additional Ni-P phase 14d is formed.

[0056] The carrier 12 is a support for the copper foil 16 to improve its handling. Typically, the carrier comprises a copper layer. Examples of such carriers include copper foil, resin films coated with metals such as copper, and glass, with copper foil being preferred. The copper foil may be either rolled copper foil or electrolytic copper foil. The carrier thickness is typically 250 μm or less, preferably 9 μm to 200 μm, and more preferably 9 μm to 150 μm.

[0057] Copper foil 16 may be any known copper foil with a carrier and is not particularly limited, but is preferably electrolytic copper foil. Copper foil 16 typically has a thickness of 18 μm or less, preferably 0.1 μm to 7.0 μm, and more preferably 1.0 μm to 3.0 μm.

[0058] If necessary, the surface of the copper foil 16 may be roughened to form a roughened layer. By providing the copper foil 16 with a roughened layer, the adhesion to the resin layer during the manufacture of the copper-clad laminate or printed circuit board can be improved. Figure 1As shown, the roughened layer comprises a plurality of roughened particles 18. These roughened particles 18 are preferably each 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 the roughened surface can preferably be performed by forming roughened particles using a metal or alloy on the copper foil 16. For example, the roughening treatment is preferably performed using a plating method that includes at least two plating steps, including a sintering step to deposit fine metal particles onto the metal foil and a cover plating step to prevent the fine metal particles from falling off.

[0059] As needed, the surface of the copper foil 16 can be subjected to an anti-rust treatment to form an anti-rust treatment layer. The anti-rust treatment preferably includes a zinc plating treatment. The zinc plating treatment can be any of a zinc plating treatment and a zinc alloy plating treatment, and the zinc alloy plating treatment is particularly preferably a zinc-nickel alloy treatment. The zinc-nickel alloy treatment can be a plating treatment that contains at least Ni and Zn, and can also contain other elements such as Sn, Cr, and Co. The Ni / Zn adhesion ratio of the zinc-nickel alloy coating is preferably 1.2 or more and 10 or less in terms of mass ratio, more preferably 2 or more and 7 or less, and further preferably 2.7 or more and 4 or less. In addition, the anti-rust treatment preferably also includes a chromate treatment, which is more preferably performed on the surface of the zinc-containing coating after the zinc plating treatment. Thus, the rust resistance can be further improved. A particularly preferred anti-rust treatment is a combination of a zinc-nickel alloy plating treatment and a subsequent chromate treatment.

[0060] If necessary, the surface of the copper foil 16 can also be treated with a silane coupling agent to form a silane coupling agent layer. This can improve moisture resistance, chemical resistance, and adhesion to adhesives, etc. The silane coupling agent layer can be formed by appropriately diluting the silane coupling agent, applying it, and drying it. Examples of silane coupling agents include epoxy functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane, or 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyl An amino-functional silane coupling agent such as trimethoxysilane, a mercapto-functional silane coupling agent such as 3-mercaptopropyltrimethoxysilane, an olefin-functional silane coupling agent such as vinyltrimethoxysilane or vinylphenyltrimethoxysilane, an acrylic-functional silane coupling agent such as 3-methacryloxypropyltrimethoxysilane, an imidazole-functional silane coupling agent such as imidazolesilane, or a triazine-functional silane coupling agent such as triazinesilane.

[0061] Therefore, the copper foil with carrier 10 preferably further comprises, on the copper foil 16, at least one layer selected from the group consisting of a roughened layer formed using a plurality of roughened particles 18, a rust-proofing layer, and a silane coupling agent layer. For example, when the copper foil with carrier 10 further comprises a roughened layer, a rust-proofing layer, and a silane coupling agent layer, the order in which these layers are formed is not particularly limited; however, the roughened layer, the rust-proofing layer, and the silane coupling agent layer are preferably stacked in this order on the copper foil 16.

[0062] Method for manufacturing copper foil with carrier

[0063] The copper foil with carrier 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 copper foil with carrier 10 of the present invention will be described below.

[0064] (1) Preparation of carrier

[0065] First, a carrier 12 is prepared as a support. Typically, the carrier 12 includes a copper layer. Examples of such a carrier 12 include copper foil, a resin film coated with copper or the like, and glass, as described above. Copper foil is preferred.

[0066] When using electrolytic copper foil as the carrier 12, a sulfuric acid-based copper electrolyte solution is used and the foil can be electrolytically formed under known conditions without particular limitation. To produce a smooth surface of the electrolytic copper foil, the electrolyte solution 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. Examples of quaternary ammonium salt polymers having a cyclic structure include diallyldimethylammonium chloride polymers.

[0067] (2) Formation of the intermediate layer

[0068] 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 sequentially form a Cr phase 14a, a Ni-P phase 14b, and a Mo-Fe-Ni phase 14c. More preferably, an additional Ni-P phase 14d is formed after the Mo-Fe-Ni phase 14c is formed.

[0069] The formation of the Cr phase 14a is preferably carried out using a solution having a Cr concentration of 0.5 g / L to 5.0 g / L (more preferably 0.5 g / L to 2.0 g / L, and even more preferably 0.5 g / L to 1.0 g / L) and a pH of 7 to 12, at a solution temperature of 5°C to 50°C and a current density of 0.5 A / dm2 Above and 20.0A / dm 2 Below (more preferably 0.5A / dm 2 Above and 10.0A / dm 2 Below, more preferably 0.5A / dm 2 Above and 5.0A / dm 2 The plating treatment is performed under the conditions of 2.0As or less and 50.0As or less (more preferably 2.0As or more and 30.0As or less, and further preferably 2.0As or more and 20.0As or less).

[0070] The Ni-P phase 14b is preferably formed using a solution having a Ni concentration of 10.0 g / L to 50.0 g / L (more preferably 10.0 g / L to 30.0 g / L, and even more preferably 10.0 g / L to 20.0 g / L), a P concentration of 5.0 g / L to 30.0 g / L (more preferably 5.0 g / L to 20.0 g / L, and even more preferably 5.0 g / L to 15.0 g / L), and a pH of 1 to 5, at a solution temperature of 5°C to 50°C and a current density of 1.0 A / dm 2 Above and 20.0A / dm 2 Below (more preferably 1.0 A / dm 2 Above and 10.0A / dm 2 Below, more preferably 1.0 A / dm 2 Above and 5.0A / dm 2 The plating treatment is performed under the conditions of 2.0As or less and 50.0As or less (more preferably 2.0As or more and 30.0As or less, and further preferably 2.0As or more and 20.0As or less).

[0071] The formation of the Mo-Fe-Ni phase 14c preferably uses a Mo concentration of 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), an Fe concentration of 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 a Ni concentration of 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, further 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, further preferably 100 g / L or more and 200 g / L or less), an ammonia-containing solution of pH 7 or more and 12 or less, at a solution temperature of 5° C. or more and 50° C. or less and a current density of 30.0 A / dm 2 Above and 70.0A / dm 2 Below (more preferably 30.0A / dm 2 Above and 60.0A / dm 2 Below, more preferably 30.0A / dm 2 Above and 50.0A / dm 2 The plating treatment is performed under the conditions of 200As or less and 1000As or less (more preferably 200As or more and 800As or less, and further preferably 200As or more and 650As or less).

[0072] The additional Ni-P phase 14d is preferably 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 Above and 10.0A / dm 2 Below (more preferably 0.2A / dm 2 Above and 5.0A / dm 2 Below, more preferably 0.2A / dm 2 Above and 2.0A / dm 2 The plating treatment is performed under the conditions that the amount of the coating is greater than 0As and less than 20.0As (more preferably, greater than 0.5As and less than 10.0As, and further preferably, greater than 1.0As and less than 5.0As).

[0073] (3) Formation of copper foil

[0074] Copper foil 16 is formed on intermediate layer 14. For example, the copper foil can be formed using wet film-forming methods such as chemical copper plating and electrolytic copper plating, dry film-forming methods such as sputtering and chemical vapor deposition, or a combination thereof. Preferably, the copper foil is formed using electrolytic copper plating. Electrolytic formation of copper foil 16 is performed using a sulfuric acid-based copper electrolyte under known conditions and is not particularly limited.

[0075] If necessary, the surface of the copper foil 16 may be roughened, rustproofed, and / or treated with a silane coupling agent to form a roughened layer, rustproofed layer, and / or silane coupling agent layer composed of a plurality of roughening particles 18. These treatments are as described above.

[0076] Copper-clad laminate

[0077] The copper foil 10 with a carrier of the present invention is preferably used for the production of copper-clad laminates for printed circuit boards. That is, according to a preferred embodiment of the present invention, a copper-clad laminate having a copper foil 10 with a carrier is provided. The copper-clad laminate comprises: a copper foil 10 with a carrier having a carrier 12, an intermediate layer 14, and a copper foil 16 in sequence; and a resin layer provided on the surface of the copper foil 16 of the copper foil 10 with a carrier (the surface of the copper foil 16 on the opposite side of the intermediate layer 14). The preferred embodiment of the copper foil 10 with a carrier is also directly applicable to the copper foil with a carrier possessed by the copper-clad laminate. The copper foil 10 with a carrier can be provided on one side of the resin layer or on both sides. 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 composite materials formed by impregnating a synthetic resin into a base material such as a synthetic resin plate, a glass plate, a glass woven fabric, a glass non-woven fabric, or paper. In addition, from the perspective of improving insulation properties, the resin layer may contain filler particles composed of various inorganic particles such as silica and alumina. 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. The resin layer such as a prepreg and / or a resin sheet may be provided on the copper foil 10 with a carrier by means of a primer resin layer pre-coated on the surface of the copper foil.

[0078] From the perspective of providing a copper-clad laminate suitable for high-frequency applications, the resin layer preferably contains a thermoplastic resin, and more preferably, most (e.g., 50% by weight or more) or most (e.g., 80% by weight or more or 90% by weight or more) of the resin components contained in the resin layer are thermoplastic resins. 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 the dielectric loss tangent of expectation and excellent heat resistance, as the more preferred example of thermoplastic resin, can enumerate polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), thermoplastic polyimide (PI), polyamideimide (PAI), fluororesin and their arbitrary combination.From the viewpoint of low dielectric constant, particularly preferred thermoplastic resin is liquid crystal polymer (LCP) and / or fluororesin.As the preferred example of fluororesin, can enumerate polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer (ETFE) and their arbitrary combination.

[0079] printed circuit boards

[0080] The copper foil 10 with a carrier of the present invention is preferably used for the production of printed circuit boards. That is, according to a preferred embodiment of the present invention, a printed circuit board having a copper foil 10 with a carrier or a method for manufacturing the same is provided. The printed circuit board of this embodiment comprises a layer structure in which a resin layer and a copper layer are stacked in sequence. In addition, the resin layer is as described above with respect to the copper-clad laminate. In short, the printed circuit board can adopt a known layer structure. As specific examples related to printed circuit boards, there can be listed: a single-sided or double-sided printed circuit board in which a circuit is formed after the copper foil of the present invention is adhered to one or both sides of a prepreg and cured to form a laminate, and a multilayer printed circuit board in which these are multilayered. In addition, as other specific examples, there can also be listed flexible printed circuit boards, COFs, TAB tapes, etc. in which a circuit is formed by forming the copper foil of the present invention on a resin film. Furthermore, other specific examples include: a copper foil coated with resin, formed with the aforementioned resin layer, laminated onto a printed circuit board using the resin layer as an insulating adhesive layer, and then forming a circuit using a modified semi-additive process (MSAP) or subtractive process, using the copper foil as all or part of the wiring layer; a build-up circuit board in which the copper foil is removed and a circuit is formed using a semi-additive process (SAP); and a direct build-up wafer in which the lamination of the resin-coated copper foil and the formation of the circuit are alternately repeated on a semiconductor integrated circuit. The copper foil with a carrier 10 of the present invention can also be preferably used in a coreless build-up method, in which an insulating resin layer and a conductive layer are alternately laminated, without using a so-called core substrate. Further specific examples include antenna elements in which a circuit is formed by laminating the resin-coated copper foil onto a substrate; electronic materials for panels / displays in which a pattern is formed by laminating the copper foil onto glass or a resin film via an adhesive layer; and electronic materials for window glass; and electromagnetic wave shielding films in which a conductive adhesive is applied to the copper foil. In particular, the printed wiring board of the present invention is suitable as a high-frequency substrate for applications such as automotive antennas, mobile phone base station antennas, high-performance servers, and collision avoidance radars used in high-frequency bands with signal frequencies of 10 GHz or higher.

[0081] Example

[0082] The present invention will be further described in detail with reference to the following examples, but the present invention is not limited to the following examples.

[0083] Examples 1 to 14

[0084] A copper foil with a carrier including a carrier, an intermediate layer, and a copper foil in this order was produced as follows.

[0085] (1) Preparation of carrier

[0086] As the copper electrolyte, a sulfuric acid copper sulfate solution with the composition shown below was used, a titanium electrode with a surface roughness Ra of 0.20 μm was used as the cathode, and a DSA (dimensionally stable anode) was used as the anode. The solution temperature was 45°C and the current density was 55 A / dm 2 Electrolysis was performed under the conditions of 400 nm to obtain an electrolytic copper foil with a thickness of 18 μm as a carrier.

[0087] <Composition of sulfuric acid-acid copper sulfate solution>

[0088] -Copper concentration: 80g / L

[0089] -Sulfuric acid concentration: 260g / L

[0090] -Bis(3-sulfopropyl) disulfide concentration: 30 mg / L

[0091] -Diallyldimethylammonium chloride polymer concentration: 50 mg / L

[0092] -Chlorine concentration: 40mg / L

[0093] (2) Formation of the intermediate layer

[0094] The resulting support was immersed in a sulfuric acid aqueous solution with a sulfuric acid concentration of 100 g / L for 60 seconds to clean the surface, and then an intermediate layer was formed on the electrode surface of the support. For Examples 1 to 13, a plating treatment was performed using a solution prepared by dissolving chromic acid in pure water to achieve the Cr concentrations shown in Table 1 and adjusting the pH to 10 by adding a potassium hydroxide aqueous solution. The Cr phase was formed at a solution temperature of 20°C and the current density and charge conditions shown in Table 1. For Example 14, no Cr phase was formed.

[0095] Thereafter, a solution prepared by dissolving sodium phosphite pentahydrate and nickel sulfate hexahydrate in pure water to give the Ni and P concentrations shown in Table 1, and adjusting the pH to 4.0 by adding a sulfuric acid aqueous solution having a sulfuric acid concentration of 300 g / L, was subjected to plating treatment at a solution temperature of 30° C. and under the conditions of the current density and the amount of electricity shown in Table 1, thereby forming a Ni-P phase. Subsequently, a solution prepared by dissolving disodium molybdate, nickel sulfate hexahydrate, iron (II) sulfate heptahydrate, and trisodium citrate dihydrate in pure water to give the Mo, Fe, Ni, and sodium citrate concentrations shown in Table 1, and further adding 50 mL of aqueous ammonia to 1 L of the solution was subjected to plating treatment at a solution temperature of 30° C. and under the conditions of the current density and the amount of electricity shown in Table 1, thereby forming a Mo-Fe-Ni phase.

[0096] For Examples 1 to 5 and Examples 7 to 14, the same solution as that used for the formation of the Ni-P phase was used to perform plating treatment to form an additional Ni-P phase at a solution temperature of 30°C and the current density and charge conditions shown in Table 1. On the other hand, for Example 6, no additional Ni-P phase was formed.

[0097] (3) Formation of copper foil

[0098] The support with the intermediate layer formed thereon was immersed in a solution of the following composition at a solution temperature of 45°C and a current density of 20 A / dm 2 Electroplating was performed under conditions of to form a copper foil with a thickness of 3 μm on the intermediate layer to obtain a copper foil with a carrier.

[0099] <Solution Composition>

[0100] -Copper concentration: 75g / L

[0101] -Free sulfuric acid concentration: 150g / L

[0102] (4) Roughening treatment

[0103] The copper foil with a carrier was immersed in a sulfuric acid aqueous solution having a sulfuric acid concentration of 100 g / L for 30 seconds to clean the surface, and then the copper foil surface of the copper foil with a carrier was subjected to a two-step roughening treatment as follows.

[0104] - The first stage of roughening treatment was carried out in two steps. 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 at a current density of 28 A / dm 2 The first electroplating was carried out under the conditions of a current density of 112 As, and then the same solution was used at a current density of 18 A / dm 2 The second electroplating was carried out under the conditions of 72As of electricity.

[0105] - The second stage of roughening treatment uses a solution with a copper concentration of 65g / L, a free sulfuric acid concentration of 100g / L and a solution temperature of 45°C, at a current density of 4.8A / dm 2 Electroplating is carried out under the conditions of 56As and 56As of electricity.

[0106] (5) Anti-rust treatment

[0107] The copper foil with carrier after roughening treatment was subjected to rust prevention treatment including zinc-nickel alloy plating and chromate treatment. First, a solution containing zinc concentration of 1g / L, nickel concentration of 2g / L and potassium pyrophosphate concentration of 80g / L was used at a liquid temperature of 40°C and a current density of 0.5A / dm 2The surface of the roughened layer and the carrier was plated with zinc-nickel alloy. 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 of , the surface treated with zinc-nickel alloy plating was chromated.

[0108] (6) Silane coupling agent treatment

[0109] A 6 g / L aqueous solution of 3-aminopropyltrimethoxysilane was adsorbed on the copper foil side of the copper foil with a carrier, and the water was evaporated using an electric heater to perform a silane coupling agent treatment. At this time, the carrier side was not treated with a silane coupling agent.

[0110] [Table 1]

[0111]

[0112] evaluate

[0113] The copper foils with carriers produced in Examples 1 to 14 were subjected to various evaluations shown below.

[0114] (a) Determination of peel strength

[0115] As fluororesin substrate, prepare PTFE substrate (RO3003 Bondply, ROGERS Corporation system, thickness 125 μm, 1ply). The copper foil with a carrier obtained by laminating the copper foil side of the PTFE substrate in a manner of being in contact with the substrate with the copper foil side having implemented surface treatment is pressed using a vacuum press under the conditions of a pressing pressure of 2.4 MPa, a temperature of 370 ° C, and a pressing time of 30 minutes to make a copper-clad laminate. On the PTFE substrate side of the copper-clad laminate obtained, a hard substrate (a glass epoxy resin substrate with a thickness of 300 μm is thermally cured) is pasted and fixed with double-sided tape to obtain a measurement sample. Then, the peel strength (gf / cm) when peeling off the carrier from the measurement sample is measured. The peel strength is measured using a desktop precision universal testing machine (Shimadzu Corporation system, AGS-50NX), according to JIS C 6481-1996, carried out under the conditions of a peeling width of 50 mm, a peeling length of 17 mm, and a peeling speed of 50 mm / min. The measurement was performed three times for each case, and the average value was adopted as the measured value. The results are shown in Table 2.

[0116] (b) Determination of Ni / Mo ratio and Fe content

[0117] After the carrier is peeled off in (a), a predetermined area (75 cm) of the peeling surface on the carrier side and the peeling surface on the copper foil side is formed. 2) was dissolved with acid, and the concentrations of Ni, Mo, and Fe in the resulting solution were analyzed using an ICP emission spectrometer (PS3520UVDD, manufactured by Hitachi High-Tech Science Corporation). The weights of Ni, Mo, and Fe per unit area were then calculated as the Ni, Mo, and Fe attachment amounts of the intermediate layer, respectively. From the obtained attachment amounts, the ratio of Ni attachment amount to Mo attachment amount (=Ni attachment amount / Mo attachment amount) was calculated as the Ni / Mo ratio, and the ratio of Fe attachment amount to the total amount of Mo, Ni, and Fe attachment amounts (=100×Fe attachment amount / (Mo attachment amount + Ni attachment amount + Fe attachment amount)) was calculated as the Fe content. The results are shown in Table 2.

[0118] (c) Obtaining XPS depth profile

[0119] After the carrier was peeled off in (a), the peeled surface on the carrier side and the peeled surface on the copper foil side were each sputtered using an ion beam using an ion gun while digging down in the depth direction (the surface opposite to the peeled surface). XPS depth profiles of the deep region including the intermediate layer were obtained. This elemental analysis was performed using a scanning dual X-ray photoelectron spectrometer (XPS) (manufactured by ULVAC-PHI, PHIQuantes) under the following measurement conditions.

[0120] (Measurement conditions)

[0121] -X-ray beam diameter: 200μmφ

[0122] -X-ray output power: 50W

[0123] -X-ray type: monochromatized Al Kα ray

[0124] - Ion gun settings: ion type Ar gas, acceleration voltage 2kV, irradiation area 3mm×3mm

[0125] -Sputtering rate: 3.7nm / min

[0126] - Determination of elements and orbitals: P 2p, Cr 3p, Fe 3p, Ni 2p3, Cu 2p3, Mo 3d

[0127] Based on the atomic concentration distributions of P, Cr, Fe, Ni, Cu, and Mo obtained by XPS depth analysis, 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, for Examples 1 to 13, it was confirmed that there were regions where the atomic concentration ratio of Cr to Cu was greater than 0.006 (Cr phase 14a), regions where the atomic concentration ratio of P to Cu was greater than 0.01 (Ni-P phase 14b), and regions where the total atomic concentration ratio of Mo, Fe, and Ni to the atomic concentration of Cu was greater than 0.2 (Mo-Fe-Ni phase 14c). For reference, 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 by XPS depth analysis of the depth region including the intermediate layer of Example 7 are plotted against the depth from the peeling surface. Figure 3 It should be noted that Figure 3 The absence of a peak corresponding to the added Ni-P phase 14d is believed to be due to the thin covering of the granular Mo-Fe-Ni phase 14c by the added Ni-P phase 14d. Meanwhile, in Example 14, the presence of a region where the atomic concentration ratio of P to Cu is 0.01 or greater (Ni-P phase) and 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 greater (Mo-Fe-Ni phase) were confirmed. However, the absence of a region where the atomic concentration ratio of Cr to Cu is 0.006 or greater (Cr phase) was confirmed.

[0128] (d) Support coverage ratio achieved using Mo-Fe-Ni phase

[0129] The carrier was prepared and the intermediate layer was formed according to (1) and (2) above. Meanwhile, a measurement sample was prepared in which the intermediate layer was exposed without forming a copper foil. A Schottky field emission scanning electron microscope (FE-SEM, manufactured by JEOL Ltd., JSM-7900F) was used to observe the measurement sample perpendicular to the surface where the intermediate layer was exposed under the following conditions to obtain an SEM image.

[0130] (SEM image acquisition conditions)

[0131] -Observation application: PC-SEM Ver7.1.0.2

[0132] -Observation conditions: Accelerating voltage 5.0kV, Tilt 0°

[0133] -Observation magnification: 20,000 times

[0134] - Image size: 1280 pixels × 1024 pixels

[0135] - Image Adjustment: From the "Image Adjustment" menu, set "Brightness" to 0 and "Gamma Correction" to 1.50. For "Contrast," based on the waveform obtained from the histogram, set the "L" bar to the left end of the waveform and the "R" bar to coincide with the first peak when viewed from the right side of the waveform.

[0136] The obtained SEM images were analyzed using image analysis software (LUZEX (Version 1.60.8.2, manufactured by NIRECO) as follows. In this image analysis, a 1260 pixel × 940 pixel area (= 25.39 μm) after removing the imaging information area from the obtained SEM images was analyzed. 2 First, the SEM image is subjected to "SIN" of "shading image processing" once, and then the threshold is set to 0 at the lower limit and 165 at the upper limit, and the binarization process is performed. For reference, the binarized SEM image obtained in Example 3 is shown in FIG. Figure 4 In the binarized SEM image, the white region is considered to be the Mo-Fe-Ni phase. Next, the binarized SEM image is subjected to the filtering processes (1) to (4) described below.

[0137] (1) Logic filter SMOOTH intensity 5

[0138] (2) Snowball filter ELIMINATE1 W intensity 3

[0139] (3) Logical filter CIRCLE strength 4

[0140] (4) Logic filter fill holes

[0141] The above operation was repeated for five different fields of view, and the average value of the values ​​calculated as the "area ratio" in the filtered SEM images was used as the ratio of the surface of the carrier on the intermediate layer side covered with the Mo-Fe-Ni phase. The results are shown in Table 2.

[0142] [Table 2]

[0143] Table 2

[0144]

[0145] Shows a comparative example.

Claims

1. A copper foil with a carrier, comprising 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, The ratio of the surface of the carrier on the intermediate layer side covered with the Mo-Fe-Ni phase is 61.00% or more and 96.00% or less, The ratio of the Ni deposition amount to the Mo deposition amount of the intermediate layer, i.e., the Ni / Mo ratio, is 2.00 or more. The ratio of the Fe deposited amount in the intermediate layer to the total amount of the Mo deposited amount, the Ni deposited amount, and the Fe deposited amount, that is, the Fe content, is 8.90% or less.

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

3. The copper foil with a carrier according to claim 1 or 2, wherein In the surface of the carrier on the intermediate layer side, a ratio of the surface covered with the Mo—Fe—Ni phase is 65.00% or more and 96.00% or less.

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

5. The copper foil with a carrier according to claim 1 or 2, wherein The Ni / Mo ratio is 3.00 or more and 5.00 or less. The copper foil with a carrier according to claim 5 , wherein The Ni / Mo ratio is 3.50 or more and 5.00 or less.

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

8. The copper foil with a carrier according to claim 7, wherein The Fe content is 1.80% or more and 5.00% or less. 9 . The copper foil with a carrier according to claim 1 , further comprising at least one layer selected from the group consisting of a roughened layer formed of a plurality of roughened particles, a rust-proofing layer, and a silane coupling agent layer. 10 . A copper-clad laminate comprising the copper foil with a carrier according to claim 1 . 11 . A printed wiring board comprising the copper foil with a carrier according to claim 1 .

12. A method for manufacturing a printed circuit board, characterized in that: A printed circuit board is produced using the copper foil with a carrier according to claim 1 or 2.

Images