WO2023182174A1 - Roughened copper foil, copper foil with carrier, copper-clad laminate, and printed wiring board - Google Patents

Roughened copper foil, copper foil with carrier, copper-clad laminate, and printed wiring board Download PDF

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Publication number
WO2023182174A1
WO2023182174A1 PCT/JP2023/010436 JP2023010436W WO2023182174A1 WO 2023182174 A1 WO2023182174 A1 WO 2023182174A1 JP 2023010436 W JP2023010436 W JP 2023010436W WO 2023182174 A1 WO2023182174 A1 WO 2023182174A1
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Prior art keywords
copper foil
roughened
filter
less
vmp
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PCT/JP2023/010436
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French (fr)
Japanese (ja)
Inventor
大輔 中島
彰太 川口
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三井金属鉱業株式会社
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Publication of WO2023182174A1 publication Critical patent/WO2023182174A1/en

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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D1/00—Electroforming
    • C25D1/04—Wires; Strips; Foils
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/16—Electroplating with layers of varying thickness
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00—Electroplating characterised by the article coated
    • C25D7/06—Wires; Strips; Foils
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/09—Use of materials for the conductive, e.g. metallic pattern

Definitions

  • the present invention relates to a roughened copper foil, a copper foil with a carrier, a copper-clad laminate, and a printed wiring board.
  • thermoplastic resins with a low dielectric constant such as fluororesins and liquid crystal polymers (LCP) have low chemical activity and therefore have low adhesion to copper foil.
  • the roughening particles have a ten-point average roughness Rzjis of 0.6 ⁇ m or more and 1.7 ⁇ m or less, and the half-width in the frequency distribution of the height of the roughening particles.
  • a copper foil having a roughened surface having a roughness of 0.9 ⁇ m or less is disclosed. According to such a copper foil, it is possible to exhibit high peel strength even to an insulating resin base material, such as a liquid crystal polymer film, to which chemical adhesion cannot be expected.
  • Patent Document 2 International Publication No. 2014/133164 discloses a copper foil having a particle size of 10 nm or more and 250 nm or less (for example, approximately spherical copper particles) attached to the copper foil to make it rough.
  • a surface-treated copper foil is disclosed that has a black, roughened surface.
  • Copper foils for high frequency applications are required to have finer roughening particles as described above, but such copper foils tend to have poor adhesion to resins (particularly thermoplastic resins).
  • existing copper foils are not necessarily sufficient in terms of both high adhesion with thermoplastic resins and excellent high frequency properties, and there is room for improvement.
  • the present inventors have recently discovered that, on the surface of a roughened copper foil, the skewness Ssk and Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, are controlled within predetermined ranges. By doing so, we have found that it is possible to achieve both high adhesion with thermoplastic resins and excellent high-frequency properties.
  • an object of the present invention is to provide a roughened copper foil that is capable of achieving both high adhesion to a thermoplastic resin and excellent high frequency properties.
  • a roughened copper foil having a roughened surface on at least one side has a skewness Ssk greater than 0.35, and Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, is 0.10 ⁇ m 3 / ⁇ m 2 or more and 0.28 ⁇ m 3 / ⁇ m2 or less
  • the Ssk is a value measured in accordance with JIS B0681-2:2018 without cutoff with an S filter and with a cutoff wavelength of 1.0 ⁇ m using an L filter
  • the above-mentioned Vmp and Vmc are values measured in accordance with JIS B0681-2:2018 without cutoff using an S filter and an L filter, and are roughened copper foils.
  • the roughened surface has a kurtosis Sku of 2.70 or more and 4.90 or less, The roughened copper foil according to aspect 1, wherein the Sku is a value measured in accordance with JIS B0681-2:2018 without cutoff by an S filter and an L filter.
  • the roughened surface has a load area ratio Smr1 of 11.2% or more that separates the protruding peak portion and the core portion, The roughness according to aspect 1 or 2, wherein the Smr1 is a value measured under conditions of a cutoff wavelength of 1.0 ⁇ m using an L filter without performing cutoff using an S filter in accordance with JIS B0681-2:2018. Chemically treated copper foil.
  • Aspect 4 The roughened copper foil according to any one of aspects 1 to 3, further comprising a rust prevention treatment layer and/or a silane coupling agent layer on the roughened surface.
  • a copper-clad laminate comprising the roughened copper foil according to any one of aspects 1 to 4.
  • a printed wiring board comprising the roughened copper foil according to any one of aspects 1 to 4.
  • FIG. 3 is a diagram for explaining the skewness Ssk measured in accordance with JIS B0681-2:2018, and is a diagram showing the surface and its height distribution when Ssk ⁇ 0.
  • FIG. 3 is a diagram for explaining the skewness Ssk measured in accordance with JIS B0681-2:2018, and is a diagram showing the surface and its height distribution when Ssk>0.
  • FIG. 2 is a diagram for explaining a load curve and a load area ratio determined in accordance with JIS B0681-2:2018.
  • FIG. 3 is a diagram for explaining the load area ratio Smr1 that separates the protruding peak portion and the core portion and the load area ratio Smr2 that separates the protruding trough portion and the core portion, which are measured in accordance with JIS B0681-2:2018.
  • FIG. 3 is a diagram for explaining the solid volume Vmp of the protruding peak portion and the solid volume Vmc of the core portion measured in accordance with JIS B0681-2:2018.
  • skewness Ssk or “Ssk” is a parameter representing the symmetry of height distribution, measured in accordance with JIS B0681-2:2018.
  • this value indicates that the height distribution is vertically symmetrical, in other words, it indicates that bumps (roughening particles, etc.) of uniform size are arranged on the surface.
  • FIG. 1A if this value is smaller than 0, it indicates that the surface has many small valleys, or in other words, that thick rounded bumps are lined up on the surface.
  • FIG. 1B if this value is greater than 0, it indicates that the surface has many fine mountains, or in other words, that the surface is dotted with elongated bumps.
  • surface load curve refers to the height at which the load area ratio is from 0% to 100%, determined in accordance with JIS B0681-2:2018.
  • the load area ratio at height c corresponds to Smr(c) in FIG.
  • Figure 3 the secant line of a load curve drawn from a load area ratio of 0% along the load curve with a difference in load area ratio of 40% is moved from the load area ratio of 0%, and the secant line The position where the slope of is the gentlest is called the center of the surface load curve.
  • the straight line that minimizes the sum of squares of deviations in the vertical axis direction with respect to this central part is called an equivalent straight line.
  • the portion included in the height range of 0% to 100% of the load area ratio of the equivalent straight line is called the core portion.
  • the portion higher than the core portion is called a protruding peak portion, and the portion lower than the core portion is called a protruding trough portion.
  • load area ratio Smr1 that separates the protruding mountain part and the core part refers to the core part measured in accordance with JIS B0681-2:2018, as shown in FIG. This is a parameter that represents the load area ratio at the intersection of the upper height of the surface and the surface load curve (i.e., the load area ratio that separates the core portion from the protruding peak portion).
  • load area ratio Smr2 that separates the protruding valley part and the core part refers to the height of the lower part of the core part measured in accordance with JIS B0681-2:2018, as shown in FIG. This parameter represents the load area ratio at the intersection of the curve and the load curve (that is, the load area ratio that separates the core portion from the protruding valley portion).
  • substantially volume Vmp of the protruding peak or “Vmp” is a parameter representing the volume of the protruding peak, measured in accordance with JIS B0681-2:2018, as shown in FIG. It is.
  • the actual volume Vmc of the core part or “Vmc” is a parameter representing the volume of the core part measured in accordance with JIS B0681-2:2018, as shown in FIG. It is.
  • Vmp and Vmc are calculated by specifying that the load area ratio Smr1 that separates the protruding peaks and the core part is 10%, and the load area ratio Smr2 that separates the protruding valley part and the core part is 80%. shall be.
  • Vmp+Vmc means a parameter calculated from the sum of the substantial volume Vmp ( ⁇ m 3 / ⁇ m 2 ) of the protruding peak portion and the substantial volume Vmc ( ⁇ m 3 / ⁇ m 2 ) of the core portion. That is, Vmp+Vmc is a parameter corresponding to the volume of the bump per unit area.
  • Sku is a parameter representing the sharpness of the height distribution, which is measured in accordance with JIS B0681-2:2018, and is also referred to as kurtosis.
  • Sku>3 there are many sharp peaks and valleys on the surface, in other words, there are many fine bumps standing on the surface.
  • Sku ⁇ 3 means that the surface is flat, in other words, thick rounded bumps are arranged on the surface.
  • Ssk, Vmp, Vmc, Sku and Smr1 are each calculated by measuring the surface profile of a predetermined measurement area (for example, a two-dimensional area of 64.397 ⁇ m x 64.463 ⁇ m) on the roughened surface using a commercially available laser microscope. be able to.
  • a predetermined measurement area for example, a two-dimensional area of 64.397 ⁇ m x 64.463 ⁇ m
  • Ssk and Smr1 are measured under conditions of a cutoff wavelength of 1.0 ⁇ m using an L filter and no cutoff using an S filter.
  • Vmp, Vmc, and Sku are measured under conditions where no cutoff is performed using the S filter and the L filter.
  • Other preferable measurement conditions and analysis conditions for the surface profile using a laser microscope will be shown in Examples below.
  • the "electrode surface" of the electrolytic copper foil refers to the surface that was in contact with the cathode during manufacture of the electrolytic copper foil.
  • the "deposition surface" of an electrolytic copper foil refers to the surface on which electrolytic copper is deposited during production of the electrolytic copper foil, that is, the surface that is not in contact with the cathode.
  • the copper foil according to the present invention is a roughened copper foil.
  • This roughened copper foil has a roughened surface on at least one side.
  • This roughened surface has a skewness Ssk greater than 0.35.
  • Vmp+Vmc which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, is 0.10 ⁇ m 3 / ⁇ m 2 or more and 0.28 ⁇ m 3 / ⁇ m 2 or less.
  • thermoplastic It can achieve both high adhesion with resin and excellent high frequency characteristics.
  • thermoplastic resins with a low dielectric constant such as fluororesins and liquid crystal polymers (LCP) have low chemical activity and therefore have low adhesion to copper foil, unlike thermosetting resins.
  • copper foil with low roughness which is advantageous in terms of high frequency characteristics, tends to inherently have poor adhesion to resin.
  • the roughened copper foil of the present invention it is possible to unexpectedly achieve both high adhesion with the thermoplastic resin and excellent high frequency characteristics (for example, reduction of skin effect).
  • Vmp+Vmc on the roughened surface is a parameter corresponding to the volume of the roughened particles, and if this Vmp+Vmc is a small value of 0.10 ⁇ m 3 / ⁇ m 2 or more and 0.28 ⁇ m 3 / ⁇ m 2 or less, the skin effect will be reduced. This results in a surface shape with fine roughening particles that are effective in reducing the amount of roughening.
  • the larger the Ssk value of the roughened surface the more fine peaks there are, that is, the more elongated roughening particles are scattered.
  • the roughened particles will have a fine vertically elongated shape.
  • the skin effect can be reduced compared to roughening particles that are thick and large in shape (Ssk ⁇ 0). As a result, it is thought that it becomes possible to achieve both high adhesion with the thermoplastic resin and excellent high frequency properties.
  • the Ssk of the roughened surface is greater than 0.35, preferably greater than 0.35 and less than or equal to 0.79, and more preferably greater than or equal to 0.36 and less than or equal to 0.57.
  • the roughened copper foil has a Vmp+Vmc of the roughened surface of 0.10 ⁇ m 3 / ⁇ m 2 or more and 0.28 ⁇ m 3 / ⁇ m 2 or less, preferably 0.10 ⁇ m 3 / ⁇ m 2 or more and 0.20 ⁇ m 3 / ⁇ m 2 or less, more preferably 0.15 ⁇ m 3 / ⁇ m 2 or more and 0.20 ⁇ m 3 / ⁇ m 2 or less.
  • Vmp of the roughened surface is not particularly limited as long as Vmp+Vmc is within the above range, but is typically 0.016 ⁇ m 3 / ⁇ m 2 or less, more typically 0.006 ⁇ m 3 / ⁇ m 2 or more.
  • Vmc of the roughened surface is not particularly limited as long as Vmp+Vmc is within the above range, but is typically 0.25 ⁇ m 3 / ⁇ m 2 or less, more typically 0.14 ⁇ m 3 / ⁇ m 2 It is 0.25 ⁇ m 3 / ⁇ m 2 or less, more typically 0.14 ⁇ m 3 / ⁇ m 2 or more and 0.20 ⁇ m 3 / ⁇ m 2 or less.
  • the roughened copper foil preferably has a Sku of 2.70 or more and 4.90 or less, more preferably 3.00 or more and 4.00 or less, and even more preferably 3.00 or more and 3.60. It is as follows. When Sku is within the above range, high adhesion to the thermoplastic resin and excellent high frequency properties can be achieved in a better balance.
  • the roughened copper foil preferably has an Smr1 of 11.2% or more on the roughened surface, more preferably 11.2% or more and 13.4% or less, and even more preferably 11.3% or more and 12.4%. % or less.
  • Smr1 is within the above range, high adhesion to the thermoplastic resin and excellent high frequency properties can be achieved in a better balance.
  • the thickness of the roughened copper foil is not particularly limited, but is preferably 0.1 ⁇ m or more and 35 ⁇ m or less, more preferably 0.5 ⁇ m or more and 5.0 ⁇ m or less, and even more preferably 1.0 ⁇ m or more and 3.0 ⁇ m or less.
  • the roughened copper foil is not limited to one in which the surface of a normal copper foil is roughened, but may be one in which the surface of a copper foil with a carrier is roughened.
  • the thickness of the roughened copper foil is the thickness that does not include the height of the roughening particles formed on the surface of the roughened surface (the thickness of the copper foil itself that constitutes the roughened copper foil) It is.
  • the roughened copper foil has a roughened surface on at least one side. That is, the roughened copper foil may have a roughened surface on both sides, or may have a roughened surface only on one side. As described above, the roughened surface typically includes a plurality of roughened particles (preferably vertically elongated roughened particles), and each of these plurality of roughened particles is preferably made of a copper particle.
  • the copper particles may be made of metallic copper or may be made of a copper alloy.
  • the roughening treatment for forming the roughened surface can be preferably performed by forming roughening particles of copper or copper alloy on the copper foil.
  • This roughening treatment is preferably performed according to a plating method that involves a two-step plating process.
  • the copper concentration is 5 g/L or more and 9 g/L or less (more preferably 7 g/L or more and 9 g/L or less)
  • the sulfuric acid concentration is 100 g/L or more and 150 g/L or less (more preferably 100 g/L or more and 150 g/L or less).
  • Electrodeposition is preferably performed using a copper sulfate solution with a tungsten concentration of 5 mg/L or more and 20 mg/L or less (more preferably 10 mg/L or more and 20 mg/L or less). This electrodeposition is carried out at a liquid temperature of 20°C or more and 50°C or less (more preferably 30°C or more and 50°C or less) and a current density of 10 A/ dm2 or more and 40 A/dm2 or less (more preferably 20 A/ dm2 or more and 40 A/dm2 or less) . (below) and an electrical quantity of 50 A ⁇ s to 200 A ⁇ s (more preferably 50 A ⁇ s to 150 A ⁇ s).
  • the copper concentration is 40 g/L or more and 70 g/L or less (more preferably 50 g/L or more and 70 g/L or less), and the sulfuric acid concentration is 100 g/L or more and 300 g/L or less (more preferably 150 g/L).
  • Electrodeposition is preferably performed using a copper sulfate solution (250 g/L or less).
  • This electrodeposition is performed at a liquid temperature of 30°C or more and 60°C or less (more preferably 40°C or more and 50°C or less) and a current density of 10 A/ dm2 or more and 40 A/dm2 or less (more preferably 20 A/dm2 or more and 40 A/dm2 or less) .
  • the plating conditions are preferably 10 A ⁇ s or more and 250 A ⁇ s or less (more preferably 10 A ⁇ s or more and 150 A ⁇ s or less).
  • the roughened copper foil may be subjected to rust prevention treatment and may have a rust prevention treatment layer formed thereon.
  • the rust prevention treatment includes plating treatment using zinc.
  • the plating treatment using zinc may be either a zinc plating treatment or a zinc alloy plating treatment, and the zinc alloy plating treatment is particularly preferably a zinc-nickel alloy treatment.
  • the zinc-nickel alloy treatment may be a plating treatment that contains at least Ni and Zn, and may further contain other elements such as Sn, Cr, and Co.
  • the Ni/Zn adhesion ratio in zinc-nickel alloy plating is preferably 1.2 or more and 10 or less, more preferably 2 or more and 7 or less, and even more preferably 2.7 or more and 4 or less, in terms of mass ratio.
  • the rust prevention treatment further includes chromate treatment, and it is more preferable that this chromate treatment is performed on the surface of the plating containing zinc after the plating treatment using zinc.
  • a particularly preferred anticorrosion treatment is a combination of zinc-nickel alloy plating treatment followed by chromate treatment.
  • the surface of the roughened copper foil may be treated with a silane coupling agent to form a silane coupling agent layer.
  • a silane coupling agent layer can be formed by appropriately diluting a silane coupling agent, applying it, and drying it.
  • silane coupling agents include epoxy-functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-aminopropyltrimethoxysilane, N-(2- aminoethyl)-3-aminopropyltrimethoxysilane, N-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, etc.
  • epoxy-functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-aminopropyltrimethoxysilane, N-(2- aminoethyl)-3-aminopropyltrimethoxysilane, N-3-(4-(3-aminopropoxy)but
  • Amino-functional silane coupling agents or mercapto-functional silane coupling agents such as 3-mercaptopropyltrimethoxysilane, or olefin-functional silane coupling agents such as vinyltrimethoxysilane, vinylphenyltrimethoxysilane, or 3-methacrylic Examples include acrylic-functional silane coupling agents such as roxypropyltrimethoxysilane, or imidazole-functional silane coupling agents such as imidazole silane, or triazine-functional silane coupling agents such as triazine silane.
  • the roughened copper foil further includes a rust prevention treatment layer and/or a silane coupling agent layer on the roughening treatment surface, and more preferably, a rust prevention treatment layer and/or a silane coupling agent layer.
  • a rust prevention treatment layer and/or a silane coupling agent layer are formed on the roughening treatment surface, the numerical values of various parameters of the roughening treatment surface in this specification are based on the rust prevention treatment layer and/or the silane coupling agent layer. It means the numerical value obtained by measuring and analyzing the roughened copper foil after the treatment layer has been formed.
  • the rust prevention layer and the silane coupling agent layer may be formed not only on the roughened surface side of the roughened copper foil but also on the side where the roughened surface is not formed.
  • the roughened copper foil of the present invention may be provided in the form of a copper foil with a carrier. That is, according to a preferred embodiment of the present invention, the method includes a carrier, a release layer provided on the carrier, and the roughened copper foil provided on the release layer with the roughened surface facing outward. A copper foil with a carrier is provided.
  • the carrier-attached copper foil may have any known layer structure, except for using the roughened copper foil of the present invention.
  • the carrier is a support for supporting the roughened copper foil to improve its handling properties, and a typical carrier includes a metal layer.
  • a typical carrier includes a metal layer.
  • Examples of such carriers include aluminum foil, copper foil, stainless steel (SUS) foil, resin films whose surfaces are metal-coated with copper or the like, glass, and the like, with copper foil being preferred.
  • the copper foil may be either a rolled copper foil or an electrolytic copper foil, but preferably an electrolytic copper foil.
  • the thickness of the carrier is typically 250 ⁇ m or less, preferably 9 ⁇ m or more and 200 ⁇ m or less.
  • the peeling layer is a layer that has the function of weakening the peeling strength of the carrier, ensuring the stability of this strength, and further suppressing mutual diffusion that may occur between the carrier and the copper foil during press molding at high temperatures.
  • the release layer may be either an organic release layer or an inorganic release layer.
  • organic components used in the organic release layer include nitrogen-containing organic compounds, sulfur-containing organic compounds, carboxylic acids, and the like.
  • nitrogen-containing organic compound include triazole compounds, imidazole compounds, etc. Among them, triazole compounds are preferred because they have easy releasability.
  • triazole compounds examples include 1,2,3-benzotriazole, carboxybenzotriazole, N',N'-bis(benzotriazolylmethyl)urea, 1H-1,2,4-triazole and 3-amino- Examples include 1H-1,2,4-triazole.
  • sulfur-containing organic compounds examples include mercaptobenzothiazole, thiocyanuric acid, 2-benzimidazolethiol, and the like.
  • carboxylic acids include monocarboxylic acids, dicarboxylic acids, and the like.
  • examples of inorganic components used in the inorganic release layer include Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, and a chromate-treated film.
  • the release layer may be formed by, for example, bringing a release layer component-containing solution into contact with at least one surface of the carrier to fix the release layer component on the surface of the carrier.
  • this contact may be carried out by dipping the carrier in the release layer component-containing solution, spraying the release layer component-containing solution, flowing down the release layer component-containing solution, or the like.
  • a method of forming a film with the release layer component by a vapor phase method such as vapor deposition or sputtering.
  • the release layer component may be fixed to the carrier surface by adsorption or drying of a solution containing the release layer component, or by electrodeposition of the release layer component in the solution containing the release layer component.
  • the thickness of the release layer is typically 1 nm or more and 1 ⁇ m or less, preferably 5 nm or more and 500 nm or less.
  • auxiliary metal layers may be provided between the release layer and the carrier and/or the roughened copper foil.
  • other functional layers include auxiliary metal layers.
  • the auxiliary metal layer consists of nickel and/or cobalt.
  • the thickness of the auxiliary metal layer is preferably 0.001 ⁇ m or more and 3 ⁇ m or less.
  • the roughened copper foil of the present invention is preferably used for producing 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 roughened copper foil is provided.
  • This copper-clad laminate includes the roughened copper foil of the present invention and a resin layer provided in close contact with the roughened surface of the roughened copper foil.
  • the roughened copper foil may be provided on one side or both sides of the resin layer.
  • the resin layer contains a resin, preferably an insulating resin.
  • the resin layer is a prepreg and/or a resin sheet.
  • Prepreg is a general term for composite materials in which a base material such as a synthetic resin plate, glass plate, glass woven fabric, glass nonwoven fabric, or paper is impregnated with synthetic resin.
  • the resin layer may contain filler particles made of various inorganic particles such as silica and alumina from the viewpoint of improving insulation properties.
  • the thickness of the resin layer is not particularly limited, but is preferably 1 ⁇ m or more and 1000 ⁇ m or less, more preferably 2 ⁇ m or more and 400 ⁇ m or less, and still more preferably 3 ⁇ m or more and 200 ⁇ m 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 roughened copper foil via a primer resin layer that is previously applied to the surface of the copper foil.
  • the resin layer preferably contains a thermoplastic resin, and more preferably most (for example, 50% by weight or more) or most ( For example, 80% by weight or more or 90% by weight or more) is thermoplastic resin.
  • thermoplastic resins include polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), and thermoplastic polyimide (PI).
  • thermoplastic resins include polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), and polysulfone.
  • thermoplastic resins include liquid crystal polymers (LCP) and/or fluororesins.
  • fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene. copolymers (ETFE), and any combination thereof.
  • the insulating resin base material it is preferable to attach the insulating resin base material to the roughened copper foil by pressing while heating.This softens the thermoplastic resin and allows it to penetrate into the fine irregularities of the roughened surface. can be set. As a result, the adhesion between the copper foil and the resin can be ensured due to the anchor effect caused by the fine irregularities (particularly the vertically elongated roughened particles) biting into the resin.
  • the roughened copper foil of the present invention is preferably used for producing printed wiring boards. That is, according to a preferred embodiment of the present invention, a printed wiring board including the roughened copper foil is provided. By using the roughened copper foil of the present invention, it is possible to achieve both excellent high frequency characteristics and high circuit adhesion in the manufacture of printed wiring boards.
  • the printed wiring board according to this embodiment includes a layered structure in which a resin layer and a copper layer are laminated.
  • the copper layer is a layer derived from the roughened copper foil of the present invention. Further, the resin layer is as described above regarding the copper-clad laminate.
  • the printed wiring board may have a known layer structure, except for using the roughened copper foil of the present invention.
  • printed wiring boards include single-sided or double-sided printed wiring boards in which the roughened copper foil of the present invention is adhered to one or both sides of prepreg to form a cured laminate, and circuits are formed on the cured laminate, and multilayered versions of these. Examples include multilayer printed wiring boards. Further, other specific examples include flexible printed wiring boards, COF, TAB tapes, etc. in which a circuit is formed by forming the roughened copper foil of the present invention on a resin film. As another specific example, a resin-coated copper foil (RCC) is formed by applying the above-mentioned resin layer to the roughened copper foil of the present invention, and the resin layer is laminated on the above-mentioned printed circuit board as an insulating adhesive layer.
  • RRCC resin-coated copper foil
  • build-up wiring boards in which circuits are formed using methods such as modified semi-additive method (MSAP) or subtractive method using the roughened copper foil as all or part of the wiring layer, and the roughened copper foil are removed.
  • MSAP modified semi-additive method
  • Examples include a build-up wiring board in which a circuit is formed using a semi-additive method (SAP), and a direct build-up on wafer in which lamination of resin-coated copper foil and circuit formation are alternately repeated on a semiconductor integrated circuit.
  • More advanced examples include antenna elements in which the resin-coated copper foil is laminated onto a base material to form a circuit, electronic materials for panels and displays, and windows in which patterns are formed by laminating the resin-coated copper foil onto glass or resin film via an adhesive layer.
  • Examples include electronic materials for glass, electromagnetic shielding films made by applying a conductive adhesive to the roughened copper foil of the present invention, and the like.
  • printed wiring boards equipped with the roughened copper foil of the present invention can be used in applications such as automotive antennas, mobile phone base station antennas, high-performance servers, and collision prevention radars used in high frequency bands of signal frequencies of 10 GHz or higher. It is suitably used as a high frequency substrate.
  • Examples 1 to 11 The roughened copper foil of the present invention was manufactured as follows.
  • the conditions for the roughening treatment at each stage were as follows. - In the first roughening treatment, sulfuric acid, copper sulfate, and optionally sodium tungstate as an inorganic additive (Examples 1 to 6, 8, and 9 Electroplating was carried out using an acidic copper sulfate solution containing ) under the electrodeposition conditions (liquid temperature, current density, and quantity of electricity) shown in Table 1. - In the second roughening treatment, an acidic copper sulfate solution containing sulfuric acid and copper sulfate was used under the electrodeposition conditions (liquid temperature, current Electroplating was carried out at the following density and electrical charge).
  • the roughened surface of the electrolytic copper foil was subjected to rust prevention treatment consisting of zinc-nickel alloy plating treatment and chromate treatment.
  • a zinc-nickel alloy plating treatment was performed using a solution containing a zinc concentration of 1 g/L, a nickel concentration of 2 g/L, and a potassium pyrophosphate concentration of 80 g/L under conditions of a liquid temperature of 40°C and a current density of 0.5 A/ dm2 . I did it.
  • the surface subjected to the zinc-nickel alloy plating treatment was subjected to chromate treatment using an aqueous solution containing 1 g/L of chromic acid under conditions of pH 12 and current density of 1 A/dm 2 .
  • Silane coupling agent treatment An aqueous solution of 3-aminopropyltrimethoxysilane with a concentration of 6 g/L is adsorbed on the roughened surface of the electrolytic copper foil, and the water is evaporated with an electric heater to form a silane cup. Ring agent treatment was performed. At this time, the silane coupling agent treatment was not performed on the surface of the electrolytic copper foil that had not been subjected to the roughening treatment.
  • the roughened surface of the roughened copper foil was measured by surface roughness analysis using a laser microscope in accordance with JIS B0681-2:2018.
  • the specific measurement conditions were as shown in Table 2.
  • the above parameters were calculated in 10 different visual fields, and the average value in all the visual fields was adopted as the surface texture parameter of the roughened surface of the sample. The results were as shown in Table 3.
  • thermoplastic resin liquid crystal polymer
  • LCP liquid crystal polymer
  • the obtained roughened copper foil was laminated on this thermoplastic resin base material so that its roughened surface was in contact with the resin base material, and using a vacuum press machine, press pressure was 4 MPa, temperature was 330°C, Pressing was performed under conditions of a pressing time of 10 minutes to produce a copper-clad laminate.
  • a circuit was formed on this copper-clad laminate by a subtractive method using a cupric chloride etching solution to produce a test board having a linear circuit with a width of 3 mm.
  • the formed test board was tested using a tabletop precision universal testing machine (AGS-50NX, manufactured by Shimadzu Corporation) in accordance with JIS C 5016-1994 method A (90° peeling).
  • the film was peeled off from the thermoplastic resin base material to measure normal peel strength (kgf/cm). When this peel strength was 0.60 kgf/cm or more, it was determined to be acceptable.
  • the results were as shown in Table 3.
  • High-frequency base materials (MEGTRON6N, manufactured by Panasonic Corporation, 45 ⁇ m thick x 2 sheets) were prepared as insulating resin base materials.
  • the obtained roughened copper foil was laminated on both sides of this insulating resin base material so that the roughened surface was in contact with the insulating resin base material, and a vacuum press was used to press the foil at a pressure of 3 MPa and a temperature of 190°C. Pressing was performed under the conditions of 90 minutes of pressing time to obtain a copper-clad laminate.
  • circuit height 18 ⁇ m, circuit width: 300 ⁇ m, circuit length: 300 mm
  • circuit length 300 mm
  • a substrate for transmission loss measurement was obtained in which a microstrip line was formed so that the characteristic impedance was 50 ⁇ 2 ⁇ .
  • the obtained transmission loss measurement board was measured using a network analyzer (manufactured by Keysight Technologies, N5225B) under the following setting conditions, and the transmission loss L 1 (dB) at 50 GHz was measured.
  • this transmission loss increase rate was 1.10 or less, it was determined to be acceptable.
  • Table 3 (Setting conditions) -IF Bandwidth: 100Hz -Frequency: 10MHz to 50GHz -Data points: 501 points -Average: Off -Calibration method: SOLT (e-cal)

Abstract

Provided is a roughened copper foil capable of achieving both high adhesion to a thermoplastic resin and excellent high-frequency characteristics. The roughened copper foil has at least one roughened surface. Provided is a roughened copper foil capable of achieving both high adhesion to a thermoplastic resin and excellent high-frequency characteristics. The roughened copper foil has at least one roughened surface. In the roughened surface, the skewness Ssk is greater than 0.35, and Vmp＋Vmc, which is the sum of the actual volume Vmp of a protruding peak portion and the actual volume Vmc of a core portion, is 0.10 μm3/μm2 to 0.25 μm3/μm2. Ssk is a value measured under the condition of an L filter-cutoff wavelength of 1.0 μm without S filter-cutoff in accordance with JIS B0681-2:2018. Vmp and Vmc are values measured in accordance with JIS B0681-2:2018 without S filter-and L filter-cutoff.

Description

粗化処理銅箔、キャリア付銅箔、銅張積層板及びプリント配線板Roughened copper foil, copper foil with carrier, copper clad laminates and printed wiring boards
　本発明は、粗化処理銅箔、キャリア付銅箔、銅張積層板及びプリント配線板に関する。 The present invention relates to a roughened copper foil, a copper foil with a carrier, a copper-clad laminate, and a printed wiring board.
　近年の携帯用電子機器等の高機能化に伴い、大量の情報の高速処理をすべく信号の高周波化が進んでおり、５Ｇ、ミリ波、基地局アンテナ等の高周波用途に適したプリント配線板が求められている。このような高周波用プリント配線板には、高周波信号を品質低下させずに伝送可能とするために、伝送損失の低減が望まれる。プリント配線板は配線パターンに加工された銅箔と絶縁樹脂基材とを備えたものであるが、伝送損失は、銅箔に起因する導体損失と、絶縁樹脂基材に起因する誘電体損失とから主としてなる。したがって、絶縁樹脂基材に起因する誘電体損失を低減すべく、低誘電率の熱可塑性樹脂を用いることができれば好都合である。しかしながら、フッ素樹脂や液晶ポリマー（ＬＣＰ）に代表される低誘電率の熱可塑性樹脂は、熱硬化性樹脂とは異なり、化学的な活性が低く、それ故銅箔との密着力が低い。 With the increasing functionality of portable electronic devices in recent years, the frequency of signals is increasing in order to process large amounts of information at high speed, and printed wiring boards are suitable for high frequency applications such as 5G, millimeter waves, and base station antennas. is required. Such a high frequency printed wiring board is desired to reduce transmission loss in order to be able to transmit high frequency signals without deteriorating quality. A printed wiring board is equipped with copper foil processed into a wiring pattern and an insulating resin base material, but transmission loss is caused by conductor loss due to the copper foil and dielectric loss due to the insulating resin base material. becomes the lord. Therefore, it would be advantageous if a thermoplastic resin with a low dielectric constant could be used in order to reduce the dielectric loss caused by the insulating resin base material. However, unlike thermosetting resins, thermoplastic resins with a low dielectric constant, such as fluororesins and liquid crystal polymers (LCP), have low chemical activity and therefore have low adhesion to copper foil.
　そこで、銅箔と熱可塑性樹脂との密着性を向上する技術が提案されている。例えば、特許文献１（国際公開第２０１６／１７４９９８号）には、０．６μｍ以上１．７μｍ以下の十点平均粗さＲｚｊｉｓを有し、かつ、粗化粒子の高さの頻度分布における半値幅が０．９μｍ以下である粗化処理面を備えた銅箔が開示されている。かかる銅箔によれば、液晶ポリマーフィルムのような化学密着が期待できない絶縁樹脂基材に対しても高い剥離強度を呈することが可能とされている。 Therefore, techniques have been proposed to improve the adhesion between copper foil and thermoplastic resin. For example, in Patent Document 1 (International Publication No. 2016/174998), the roughening particles have a ten-point average roughness Rzjis of 0.6 μm or more and 1.7 μm or less, and the half-width in the frequency distribution of the height of the roughening particles. A copper foil having a roughened surface having a roughness of 0.9 μm or less is disclosed. According to such a copper foil, it is possible to exhibit high peel strength even to an insulating resin base material, such as a liquid crystal polymer film, to which chemical adhesion cannot be expected.
　一方、導体損失は、高周波になるほど顕著に現れる銅箔の表皮効果によって増大しうる。したがって、高周波用途における伝送損失を抑制するには、銅箔の表皮効果を低減すべく粗化粒子の微細化が求められる。かかる微細な粗化粒子を有する銅箔として、例えば、特許文献２（国際公開第２０１４／１３３１６４号）には、粒径１０ｎｍ以上２５０ｎｍ以下の銅粒子（例えば略球状銅粒子）を付着させて粗化した黒色粗化面を備える表面処理銅箔が開示されている。 On the other hand, conductor loss can increase due to the skin effect of copper foil, which becomes more pronounced as the frequency increases. Therefore, in order to suppress transmission loss in high frequency applications, it is required to make the roughening particles finer in order to reduce the skin effect of copper foil. As a copper foil having such fine roughening particles, for example, Patent Document 2 (International Publication No. 2014/133164) discloses a copper foil having a particle size of 10 nm or more and 250 nm or less (for example, approximately spherical copper particles) attached to the copper foil to make it rough. A surface-treated copper foil is disclosed that has a black, roughened surface.
国際公開第２０１６／１７４９９８号International Publication No. 2016/174998 国際公開第２０１４／１３３１６４号International Publication No. 2014/133164
　高周波用途の銅箔では、上述したとおり粗化粒子を微細化することが求められるものの、このような銅箔は樹脂（とりわけ熱可塑性樹脂）との密着性が低下しやすい。この点、既存の銅箔は、熱可塑性樹脂との高い密着性と優れた高周波特性との両立という観点で必ずしも十分なものとはいえず、改善の余地がある。 Copper foils for high frequency applications are required to have finer roughening particles as described above, but such copper foils tend to have poor adhesion to resins (particularly thermoplastic resins). In this regard, existing copper foils are not necessarily sufficient in terms of both high adhesion with thermoplastic resins and excellent high frequency properties, and there is room for improvement.
　本発明者らは、今般、粗化処理銅箔の表面において、スキューネスＳｓｋと、突出山部の実体体積Ｖｍｐ及びコア部の実体体積Ｖｍｃの和であるＶｍｐ＋Ｖｍｃとをそれぞれ所定の範囲内に制御することにより、熱可塑性樹脂との高い密着性と優れた高周波特性とを両立できるとの知見を得た。 The present inventors have recently discovered that, on the surface of a roughened copper foil, the skewness Ssk and Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, are controlled within predetermined ranges. By doing so, we have found that it is possible to achieve both high adhesion with thermoplastic resins and excellent high-frequency properties.
　したがって、本発明の目的は、熱可塑性樹脂との高い密着性と優れた高周波特性とを両立可能な粗化処理銅箔を提供することにある。 Therefore, an object of the present invention is to provide a roughened copper foil that is capable of achieving both high adhesion to a thermoplastic resin and excellent high frequency properties.
　本発明によれば、以下の態様が提供される。
［態様１］
　少なくとも一方の側に粗化処理面を有する粗化処理銅箔であって、
　前記粗化処理面は、スキューネスＳｓｋが０．３５より大きく、かつ、突出山部の実体体積Ｖｍｐ及びコア部の実体体積Ｖｍｃの和であるＶｍｐ＋Ｖｍｃが０．１０μｍ３／μｍ２以上０．２８μｍ３／μｍ２以下であり、
　前記Ｓｓｋは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルターによるカットオフを行わず、Ｌフィルターによるカットオフ波長１．０μｍの条件で測定される値であり、
　前記Ｖｍｐ及びＶｍｃは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルター及びＬフィルターによるカットオフを行わない条件で測定される値である、粗化処理銅箔。
［態様２］
　前記粗化処理面は、クルトシスＳｋｕが２．７０以上４．９０以下であり、
　前記Ｓｋｕは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルター及びＬフィルターによるカットオフを行わない条件で測定される値である、態様１に記載の粗化処理銅箔。
［態様３］
　前記粗化処理面は、突出山部とコア部を分離する負荷面積率Ｓｍｒ１が１１．２％以上であり、
　前記Ｓｍｒ１は、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルターによるカットオフを行わず、Ｌフィルターによるカットオフ波長１．０μｍの条件で測定される値である、態様１又は２に記載の粗化処理銅箔。
［態様４］
　前記粗化処理面に防錆処理層及び／又はシランカップリング剤層をさらに備えた、態様１～３のいずれか一つに記載の粗化処理銅箔。
［態様５］
　キャリアと、該キャリア上に設けられた剥離層と、該剥離層上に前記粗化処理面を外側にして設けられた態様１～４のいずれか一つに記載の粗化処理銅箔とを備えた、キャリア付銅箔。
［態様６］
　態様１～４のいずれか一つに記載の粗化処理銅箔を備えた、銅張積層板。
［態様７］
　態様１～４のいずれか一つに記載の粗化処理銅箔を備えた、プリント配線板。 According to the present invention, the following aspects are provided.
[Aspect 1]
A roughened copper foil having a roughened surface on at least one side,
The roughened surface has a skewness Ssk greater than 0.35, and Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, is 0.10 μm 3 /μm 2 or more and 0.28 μm 3 / μm2 or less,
The Ssk is a value measured in accordance with JIS B0681-2:2018 without cutoff with an S filter and with a cutoff wavelength of 1.0 μm using an L filter,
The above-mentioned Vmp and Vmc are values measured in accordance with JIS B0681-2:2018 without cutoff using an S filter and an L filter, and are roughened copper foils.
[Aspect 2]
The roughened surface has a kurtosis Sku of 2.70 or more and 4.90 or less,
The roughened copper foil according to aspect 1, wherein the Sku is a value measured in accordance with JIS B0681-2:2018 without cutoff by an S filter and an L filter.
[Aspect 3]
The roughened surface has a load area ratio Smr1 of 11.2% or more that separates the protruding peak portion and the core portion,
The roughness according to aspect 1 or 2, wherein the Smr1 is a value measured under conditions of a cutoff wavelength of 1.0 μm using an L filter without performing cutoff using an S filter in accordance with JIS B0681-2:2018. Chemically treated copper foil.
[Aspect 4]
The roughened copper foil according to any one of aspects 1 to 3, further comprising a rust prevention treatment layer and/or a silane coupling agent layer on the roughened surface.
[Aspect 5]
A carrier, a release layer provided on the carrier, and the roughened copper foil according to any one of aspects 1 to 4 provided on the release layer with the roughened surface facing outward. Copper foil with carrier.
[Aspect 6]
A copper-clad laminate comprising the roughened copper foil according to any one of aspects 1 to 4.
[Aspect 7]
A printed wiring board comprising the roughened copper foil according to any one of aspects 1 to 4.
ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定されるスキューネスＳｓｋを説明するための図であり、Ｓｓｋ＜０の場合の表面及びその高さ分布を示す図である。FIG. 3 is a diagram for explaining the skewness Ssk measured in accordance with JIS B0681-2:2018, and is a diagram showing the surface and its height distribution when Ssk<0. ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定されるスキューネスＳｓｋを説明するための図であり、Ｓｓｋ＞０の場合の表面及びその高さ分布を示す図である。FIG. 3 is a diagram for explaining the skewness Ssk measured in accordance with JIS B0681-2:2018, and is a diagram showing the surface and its height distribution when Ssk>0. ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して決定される負荷曲線及び負荷面積率を説明するための図である。FIG. 2 is a diagram for explaining a load curve and a load area ratio determined in accordance with JIS B0681-2:2018. ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される突出山部とコア部を分離する負荷面積率Ｓｍｒ１、及び突出谷部とコア部を分離する負荷面積率Ｓｍｒ２を説明するための図である。FIG. 3 is a diagram for explaining the load area ratio Smr1 that separates the protruding peak portion and the core portion and the load area ratio Smr2 that separates the protruding trough portion and the core portion, which are measured in accordance with JIS B0681-2:2018. ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される突出山部の実体体積Ｖｍｐ及びコア部の実体体積Ｖｍｃを説明するための図である。FIG. 3 is a diagram for explaining the solid volume Vmp of the protruding peak portion and the solid volume Vmc of the core portion measured in accordance with JIS B0681-2:2018.
　定義
　本発明を特定するために用いられる用語ないしパラメータの定義を以下に示す。 Definitions Definitions of terms and parameters used to specify the present invention are shown below.
　本明細書において「スキューネスＳｓｋ」又は「Ｓｓｋ」とは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される、高さ分布の対称性を表すパラメータである。この値が０の場合は、高さ分布が上下に対称であることを示し、換言すれば大きさの揃ったコブ（粗化粒子等）が表面に並んでいることを示す。また、図１Ａに示されるように、この値が０より小さい場合は、細かい谷が多い表面であることを示し、換言すれば丸みを帯びた太いコブが表面に並んでいることを示す。一方、図１Ｂに示されるように、この値が０より大きい場合は、細かい山が多い表面であることを示し、換言すれば細長いコブが表面に点在していることを示す。 In this specification, "skewness Ssk" or "Ssk" is a parameter representing the symmetry of height distribution, measured in accordance with JIS B0681-2:2018. When this value is 0, it indicates that the height distribution is vertically symmetrical, in other words, it indicates that bumps (roughening particles, etc.) of uniform size are arranged on the surface. Further, as shown in FIG. 1A, if this value is smaller than 0, it indicates that the surface has many small valleys, or in other words, that thick rounded bumps are lined up on the surface. On the other hand, as shown in FIG. 1B, if this value is greater than 0, it indicates that the surface has many fine mountains, or in other words, that the surface is dotted with elongated bumps.
　本明細書において「面の負荷曲線」（以下、単に「負荷曲線」という）とは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して決定される、負荷面積率が０％から１００％となる高さを表した曲線をいう。負荷面積率とは、図２に示されるように、ある高さｃ以上の領域の面積を表すパラメータである。高さｃでの負荷面積率は図２におけるＳｍｒ（ｃ）に相当する。図３に示されるように、負荷面積率が０％から負荷曲線に沿って負荷面積率の差を４０％にして引いた負荷曲線の割線を、負荷面積率０％から移動させていき、割線の傾斜が最も緩くなる位置を面の負荷曲線の中央部分という。この中央部分に対して、縦軸方向の偏差の二乗和が最小になる直線を等価直線という。等価直線の負荷面積率０％から１００％の高さの範囲に含まれる部分をコア部という。コア部より高い部分を突出山部といい、コア部より低い部分は突出谷部という。 In this specification, "surface load curve" (hereinafter simply referred to as "load curve") refers to the height at which the load area ratio is from 0% to 100%, determined in accordance with JIS B0681-2:2018. A curve that represents As shown in FIG. 2, the load area ratio is a parameter representing the area of a region having a certain height c or more. The load area ratio at height c corresponds to Smr(c) in FIG. As shown in Figure 3, the secant line of a load curve drawn from a load area ratio of 0% along the load curve with a difference in load area ratio of 40% is moved from the load area ratio of 0%, and the secant line The position where the slope of is the gentlest is called the center of the surface load curve. The straight line that minimizes the sum of squares of deviations in the vertical axis direction with respect to this central part is called an equivalent straight line. The portion included in the height range of 0% to 100% of the load area ratio of the equivalent straight line is called the core portion. The portion higher than the core portion is called a protruding peak portion, and the portion lower than the core portion is called a protruding trough portion.
　本明細書において「突出山部とコア部を分離する負荷面積率Ｓｍｒ１」又は「Ｓｍｒ１」とは、図３に示されるように、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される、コア部の上部の高さと面の負荷曲線の交点における負荷面積率（すなわちコア部と突出山部を分ける負荷面積率）を表すパラメータである。本明細書において「突出谷部とコア部を分離する負荷面積率Ｓｍｒ２」とは、図３に示されるように、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される、コア部の下部の高さと負荷曲線の交点における負荷面積率（すなわちコア部と突出谷部をわける負荷面積率）を表すパラメータである。 In this specification, "load area ratio Smr1 that separates the protruding mountain part and the core part" or "Smr1" refers to the core part measured in accordance with JIS B0681-2:2018, as shown in FIG. This is a parameter that represents the load area ratio at the intersection of the upper height of the surface and the surface load curve (i.e., the load area ratio that separates the core portion from the protruding peak portion). In this specification, "load area ratio Smr2 that separates the protruding valley part and the core part" refers to the height of the lower part of the core part measured in accordance with JIS B0681-2:2018, as shown in FIG. This parameter represents the load area ratio at the intersection of the curve and the load curve (that is, the load area ratio that separates the core portion from the protruding valley portion).
　本明細書において「突出山部の実体体積Ｖｍｐ」又は「Ｖｍｐ」とは、図４に示されるように、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される、突出山部の体積を表すパラメータである。また、本明細書において「コア部の実体体積Ｖｍｃ」又は「Ｖｍｃ」とは、図４に示されるように、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される、コア部の体積を表すパラメータである。本明細書では、突出山部とコア部を分離する負荷面積率Ｓｍｒ１を１０％、及び突出谷部とコア部を分離する負荷面積率Ｓｍｒ２を８０％と指定してＶｍｐ及びＶｍｃを算出するものとする。 In this specification, "substantive volume Vmp of the protruding peak" or "Vmp" is a parameter representing the volume of the protruding peak, measured in accordance with JIS B0681-2:2018, as shown in FIG. It is. In addition, in this specification, "the actual volume Vmc of the core part" or "Vmc" is a parameter representing the volume of the core part measured in accordance with JIS B0681-2:2018, as shown in FIG. It is. In this specification, Vmp and Vmc are calculated by specifying that the load area ratio Smr1 that separates the protruding peaks and the core part is 10%, and the load area ratio Smr2 that separates the protruding valley part and the core part is 80%. shall be.
　本明細書において「Ｖｍｐ＋Ｖｍｃ」とは、突出山部の実体体積Ｖｍｐ（μｍ３／μｍ２）及びコア部の実体体積Ｖｍｃ（μｍ３／μｍ２）の和により算出されるパラメータを意味する。すなわち、Ｖｍｐ＋Ｖｍｃは単位面積当たりのコブの体積に対応するパラメータである。 In this specification, "Vmp+Vmc" means a parameter calculated from the sum of the substantial volume Vmp (μm 3 /μm 2 ) of the protruding peak portion and the substantial volume Vmc (μm 3 /μm 2 ) of the core portion. That is, Vmp+Vmc is a parameter corresponding to the volume of the bump per unit area.
　本明細書において、「クルトシスＳｋｕ」とは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠して測定される、高さ分布の鋭さを表すパラメータであり、尖り度とも称される。Ｓｋｕ＝３は高さ分布が正規分布であることを意味し、換言すれば大きさの揃ったコブが表面に並んでいることを示す。Ｓｋｕ＞３であると表面に鋭い山や谷が多く、換言すれば表面に立っている微細なコブが多いことを示す。Ｓｋｕ＜３であると表面が平坦であることを意味し、換言すれば丸みを帯びた太いコブが表面に並んでいることを示す。 In this specification, "kurtosis Sku" is a parameter representing the sharpness of the height distribution, which is measured in accordance with JIS B0681-2:2018, and is also referred to as kurtosis. Sku=3 means that the height distribution is a normal distribution, in other words, it shows that bumps of uniform size are lined up on the surface. When Sku>3, there are many sharp peaks and valleys on the surface, in other words, there are many fine bumps standing on the surface. Sku<3 means that the surface is flat, in other words, thick rounded bumps are arranged on the surface.
　Ｓｓｋ、Ｖｍｐ、Ｖｍｃ、Ｓｋｕ及びＳｍｒ１は、粗化処理面における所定の測定領域（例えば６４．３９７μｍ×６４．４６３μｍの二次元領域）の表面プロファイルを市販のレーザー顕微鏡で測定することによりそれぞれ算出することができる。本明細書において、Ｓｓｋ及びＳｍｒ１はＳフィルターによるカットオフを行わず、Ｌフィルターによるカットオフ波長１．０μｍの条件で測定されるものとする。一方、Ｖｍｐ、Ｖｍｃ及びＳｋｕはＳフィルター及びＬフィルターによるカットオフを行わない条件で測定されるものとする。その他、レーザー顕微鏡による表面プロファイルの好ましい測定条件及び解析条件については後述の実施例に示すものとする。 Ssk, Vmp, Vmc, Sku and Smr1 are each calculated by measuring the surface profile of a predetermined measurement area (for example, a two-dimensional area of 64.397 μm x 64.463 μm) on the roughened surface using a commercially available laser microscope. be able to. In this specification, it is assumed that Ssk and Smr1 are measured under conditions of a cutoff wavelength of 1.0 μm using an L filter and no cutoff using an S filter. On the other hand, it is assumed that Vmp, Vmc, and Sku are measured under conditions where no cutoff is performed using the S filter and the L filter. Other preferable measurement conditions and analysis conditions for the surface profile using a laser microscope will be shown in Examples below.
　本明細書において、電解銅箔の「電極面」とは、電解銅箔製造時に陰極と接していた側の面を指す。 In this specification, the "electrode surface" of the electrolytic copper foil refers to the surface that was in contact with the cathode during manufacture of the electrolytic copper foil.
　本明細書において、電解銅箔の「析出面」とは、電解銅箔製造時に電解銅が析出されていく側の面、すなわち陰極と接していない側の面を指す。 As used herein, the "deposition surface" of an electrolytic copper foil refers to the surface on which electrolytic copper is deposited during production of the electrolytic copper foil, that is, the surface that is not in contact with the cathode.
　粗化処理銅箔
　本発明による銅箔は粗化処理銅箔である。この粗化処理銅箔は、少なくとも一方の側に粗化処理面を有する。この粗化処理面は、スキューネスＳｓｋが０．３５より大きい。また、突出山部の実体体積Ｖｍｐ及びコア部の実体体積Ｖｍｃの和であるＶｍｐ＋Ｖｍｃが０．１０μｍ３／μｍ２以上０．２８μｍ３／μｍ２以下である。このように粗化処理銅箔の表面において、スキューネスＳｓｋと、突出山部の実体体積Ｖｍｐ及びコア部の実体体積Ｖｍｃの和であるＶｍｐ＋Ｖｍｃとをそれぞれ所定の範囲内に制御することにより、熱可塑性樹脂との高い密着性と優れた高周波特性とを両立できる。 Roughened Copper Foil The copper foil according to the present invention is a roughened copper foil. This roughened copper foil has a roughened surface on at least one side. This roughened surface has a skewness Ssk greater than 0.35. Further, Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, is 0.10 μm 3 /μm 2 or more and 0.28 μm 3 /μm 2 or less. In this way, on the surface of the roughened copper foil, by controlling the skewness Ssk and Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak part and the substantial volume Vmc of the core part, within predetermined ranges, thermoplastic It can achieve both high adhesion with resin and excellent high frequency characteristics.
　上述したとおり、高周波用途における伝送損失を抑制するには、銅箔の表皮効果を低減すべく粗化粒子の微細化が求められる。しかしながら、かかる微細な粗化粒子を有する銅箔は樹脂基材とのアンカー効果（すなわち銅箔表面の凹凸を利用した物理的な密着性向上効果）が低減する結果、樹脂との密着性に劣るものとなりやすい。特に、フッ素樹脂や液晶ポリマー（ＬＣＰ）に代表される低誘電率の熱可塑性樹脂は、熱硬化性樹脂とは異なり、化学的な活性が低く、それ故銅箔との密着力が低い。このように、高周波特性という点で有利な低粗度の銅箔は、本来的に樹脂との密着力に劣るものとなりやすい。これに対して、本発明の粗化処理銅箔によれば、熱可塑性樹脂との高い密着性と優れた高周波特性（例えば表皮効果の低減）とを予想外にも両立することができる。 As mentioned above, in order to suppress transmission loss in high frequency applications, it is required to make the roughening particles finer in order to reduce the skin effect of copper foil. However, copper foil with such fine roughening particles has poor adhesion with resin as a result of a reduced anchoring effect with the resin base material (i.e., the effect of improving physical adhesion using the unevenness of the surface of the copper foil). It's easy to become a thing. In particular, thermoplastic resins with a low dielectric constant, such as fluororesins and liquid crystal polymers (LCP), have low chemical activity and therefore have low adhesion to copper foil, unlike thermosetting resins. As described above, copper foil with low roughness, which is advantageous in terms of high frequency characteristics, tends to inherently have poor adhesion to resin. On the other hand, according to the roughened copper foil of the present invention, it is possible to unexpectedly achieve both high adhesion with the thermoplastic resin and excellent high frequency characteristics (for example, reduction of skin effect).
　樹脂との高い密着性と、優れた高周波特性との両立を可能とするメカニズムは必ずしも定かではないが、例えば、以下のようなものと考えられる。すなわち、粗化処理面におけるＶｍｐ＋Ｖｍｃは粗化粒子の体積に対応するパラメータであり、このＶｍｐ＋Ｖｍｃが０．１０μｍ３／μｍ２以上０．２８μｍ３／μｍ２以下という小さい値であると、表皮効果の低減に有効な微細な粗化粒子を有する表面形状となる。一方、粗化処理面のＳｓｋは、その数値が大きいほど細かい山が多い、つまり細長い粗化粒子が点在しているものとなる。したがって、粗化処理面のＳｓｋが０．３５より大きい値であると、粗化粒子が微細な縦長の形状を有するものとなる。これにより、従来の略球状の粗化粒子（Ｓｓｋ＝０．２～０．３程度）や、高さが極めて低く均一な粗化粒子（Ｓｓｋ＝０～０．１程度）等と比べて、熱可塑性樹脂基材との高いアンカー効果を発揮できる。また、形状が太く大きい粗化粒子（Ｓｓｋ＜０）と比べて、表皮効果を低減することができる。その結果、熱可塑性樹脂との高い密着性と、優れた高周波特性とを両立することが可能となると考えられる。 Although the mechanism that makes it possible to achieve both high adhesion with resin and excellent high frequency properties is not necessarily clear, it is thought to be, for example, as follows. That is, Vmp+Vmc on the roughened surface is a parameter corresponding to the volume of the roughened particles, and if this Vmp+Vmc is a small value of 0.10 μm 3 /μm 2 or more and 0.28 μm 3 /μm 2 or less, the skin effect will be reduced. This results in a surface shape with fine roughening particles that are effective in reducing the amount of roughening. On the other hand, the larger the Ssk value of the roughened surface, the more fine peaks there are, that is, the more elongated roughening particles are scattered. Therefore, if the Ssk of the roughened surface is larger than 0.35, the roughened particles will have a fine vertically elongated shape. As a result, compared to conventional approximately spherical roughening particles (Ssk = about 0.2 to 0.3) and uniform roughening particles with extremely low height (Ssk = about 0 to 0.1), It can exhibit a high anchoring effect with thermoplastic resin base materials. Furthermore, the skin effect can be reduced compared to roughening particles that are thick and large in shape (Ssk<0). As a result, it is thought that it becomes possible to achieve both high adhesion with the thermoplastic resin and excellent high frequency properties.
　したがって、粗化処理銅箔は、粗化処理面のＳｓｋが０．３５より大きく、好ましくは０．３５より大きく０．７９以下、より好ましくは０．３６以上０．５７以下である。 Therefore, in the roughened copper foil, the Ssk of the roughened surface is greater than 0.35, preferably greater than 0.35 and less than or equal to 0.79, and more preferably greater than or equal to 0.36 and less than or equal to 0.57.
　また、粗化処理銅箔は、粗化処理面のＶｍｐ＋Ｖｍｃが０．１０μｍ３／μｍ２以上０．２８μｍ３／μｍ２以下であり、好ましくは０．１０μｍ３／μｍ２以上０．２０μｍ３／μｍ２以下、より好ましくは０．１５μｍ３／μｍ２以上０．２０μｍ３／μｍ２以下である。粗化処理面のＶｍｐは、Ｖｍｐ＋Ｖｍｃが上記範囲内であるかぎり特に限定されないが、典型的には０．０１６μｍ３／μｍ２以下であり、より典型的には０．００６μｍ３／μｍ２以上０．０１５μｍ３／μｍ２以下、さらに典型的には０．００７μｍ３／μｍ２以上０．０１５μｍ３／μｍ２以下である。また、粗化処理面のＶｍｃは、Ｖｍｐ＋Ｖｍｃが上記範囲内であるかぎり特に限定されないが、典型的には０．２５μｍ３／μｍ２以下であり、より典型的には０．１４μｍ３／μｍ２以上０．２５μｍ３／μｍ２以下、さらに典型的には０．１４μｍ３／μｍ２以上０．２０μｍ３／μｍ２以下である。 Further, the roughened copper foil has a Vmp+Vmc of the roughened surface of 0.10 μm 3 /μm 2 or more and 0.28 μm 3 /μm 2 or less, preferably 0.10 μm 3 /μm 2 or more and 0.20 μm 3 / μm 2 or less, more preferably 0.15 μm 3 /μm 2 or more and 0.20 μm 3 /μm 2 or less. Vmp of the roughened surface is not particularly limited as long as Vmp+Vmc is within the above range, but is typically 0.016 μm 3 /μm 2 or less, more typically 0.006 μm 3 /μm 2 or more. .015 μm 3 /μm 2 or less, more typically 0.007 μm 3 /μm 2 or more and 0.015 μm 3 /μm 2 or less. Further, Vmc of the roughened surface is not particularly limited as long as Vmp+Vmc is within the above range, but is typically 0.25 μm 3 /μm 2 or less, more typically 0.14 μm 3 /μm 2 It is 0.25 μm 3 /μm 2 or less, more typically 0.14 μm 3 /μm 2 or more and 0.20 μm 3 /μm 2 or less.
　粗化処理銅箔は、粗化処理面のＳｋｕが２．７０以上４．９０以下であるのが好ましく、より好ましくは３．００以上４．００以下、さらに好ましくは３．００以上３．６０以下である。Ｓｋｕが上記範囲内であると、熱可塑性樹脂との高い密着性と、優れた高周波特性とをより一層バランス良く実現できる。 The roughened copper foil preferably has a Sku of 2.70 or more and 4.90 or less, more preferably 3.00 or more and 4.00 or less, and even more preferably 3.00 or more and 3.60. It is as follows. When Sku is within the above range, high adhesion to the thermoplastic resin and excellent high frequency properties can be achieved in a better balance.
　粗化処理銅箔は、粗化処理面のＳｍｒ１が１１．２％以上であるのが好ましく、より好ましくは１１．２％以上１３．４％以下、さらに好ましくは１１．３％以上１２．４％以下である。Ｓｍｒ１が上記範囲内であると、熱可塑性樹脂との高い密着性と、優れた高周波特性とをより一層バランス良く実現できる。 The roughened copper foil preferably has an Smr1 of 11.2% or more on the roughened surface, more preferably 11.2% or more and 13.4% or less, and even more preferably 11.3% or more and 12.4%. % or less. When Smr1 is within the above range, high adhesion to the thermoplastic resin and excellent high frequency properties can be achieved in a better balance.
　粗化処理銅箔の厚さは特に限定されないが、０．１μｍ以上３５μｍ以下が好ましく、より好ましくは０．５μｍ以上５．０μｍ以下、さらに好ましくは１．０μｍ以上３．０μｍ以下である。なお、粗化処理銅箔は、通常の銅箔の表面に粗化処理を行ったものに限らず、キャリア付銅箔の銅箔表面に粗化処理を行ったものであってもよい。ここで、粗化処理銅箔の厚さは、粗化処理面の表面に形成された粗化粒子の高さを含まない厚さ（粗化処理銅箔を構成する銅箔自体の厚さ）である。 The thickness of the roughened copper foil is not particularly limited, but is preferably 0.1 μm or more and 35 μm or less, more preferably 0.5 μm or more and 5.0 μm or less, and even more preferably 1.0 μm or more and 3.0 μm or less. Note that the roughened copper foil is not limited to one in which the surface of a normal copper foil is roughened, but may be one in which the surface of a copper foil with a carrier is roughened. Here, the thickness of the roughened copper foil is the thickness that does not include the height of the roughening particles formed on the surface of the roughened surface (the thickness of the copper foil itself that constitutes the roughened copper foil) It is.
　粗化処理銅箔は、少なくとも一方の側に粗化処理面を有する。すなわち、粗化処理銅箔は両側に粗化処理面を有するものであってもよいし、一方の側にのみ粗化処理面を有するものであってもよい。上述したとおり粗化処理面は、典型的には複数の粗化粒子（好ましくは縦長形状の粗化粒子）を備えてなり、これら複数の粗化粒子はそれぞれ銅粒子からなるのが好ましい。銅粒子は金属銅からなるものであってもよいし、銅合金からなるものであってもよい。 The roughened copper foil has a roughened surface on at least one side. That is, the roughened copper foil may have a roughened surface on both sides, or may have a roughened surface only on one side. As described above, the roughened surface typically includes a plurality of roughened particles (preferably vertically elongated roughened particles), and each of these plurality of roughened particles is preferably made of a copper particle. The copper particles may be made of metallic copper or may be made of a copper alloy.
　粗化処理面を形成するための粗化処理は、銅箔の上に銅又は銅合金で粗化粒子を形成することにより好ましく行うことができる。この粗化処理は、２段階のめっき工程を経るめっき手法に従って行われるのが好ましい。この場合、１段階目のめっき工程では、銅濃度５ｇ／Ｌ以上９ｇ／Ｌ以下（より好ましくは７ｇ／Ｌ以上９ｇ／Ｌ以下）、硫酸濃度１００ｇ／Ｌ以上１５０ｇ／Ｌ以下（より好ましくは１００ｇ／Ｌ以上１３０ｇ／Ｌ以下）及びタングステン濃度５ｍｇ／Ｌ以上２０ｍｇ／Ｌ以下（より好ましくは１０ｍｇ／Ｌ以上２０ｍｇ／Ｌ以下）の硫酸銅溶液を用いて電着を行うのが好ましい。この電着は、液温２０℃以上５０℃以下（より好ましくは３０℃以上５０℃以下）、電流密度１０Ａ／ｄｍ２以上４０Ａ／ｄｍ２以下（より好ましくは２０Ａ／ｄｍ２以上４０Ａ／ｄｍ２以下）及び電気量５０Ａ・ｓ以上２００Ａ・ｓ以下（より好ましくは５０Ａ・ｓ以上１５０Ａ・ｓ以下）のめっき条件で行うのが好ましい。とりわけ、１段階目のめっき工程において、銅濃度が従来の手法よりも低く、かつ、上記濃度範囲内の無機添加剤を含む硫酸銅溶液を用いることで、微細な縦長形状の粗化粒子を処理表面に形成しやすくなる。２段階目のめっき工程では、銅濃度４０ｇ／Ｌ以上７０ｇ／Ｌ以下（より好ましくは５０ｇ／Ｌ以上７０ｇ／Ｌ以下）、及び硫酸濃度１００ｇ／Ｌ以上３００ｇ／Ｌ以下（より好ましくは１５０ｇ／Ｌ以上２５０ｇ／Ｌ以下）の硫酸銅溶液を用いて電着を行うのが好ましい。この電着は、液温３０℃以上６０℃以下（より好ましくは４０℃以上５０℃以下）、電流密度１０Ａ／ｄｍ２以上４０Ａ／ｄｍ２以下（より好ましくは２０Ａ／ｄｍ２以上４０Ａ／ｄｍ２以下）、及び電気量１０Ａ・ｓ以上２５０Ａ・ｓ以下（より好ましくは１０Ａ・ｓ以上１５０Ａ・ｓ以下）のめっき条件で行うのが好ましい。このようなめっき工程を経ることで、上述した表面パラメータを満足するのに好都合な粗化粒子を処理表面に形成しやすくなる。 The roughening treatment for forming the roughened surface can be preferably performed by forming roughening particles of copper or copper alloy on the copper foil. This roughening treatment is preferably performed according to a plating method that involves a two-step plating process. In this case, in the first step plating process, the copper concentration is 5 g/L or more and 9 g/L or less (more preferably 7 g/L or more and 9 g/L or less), and the sulfuric acid concentration is 100 g/L or more and 150 g/L or less (more preferably 100 g/L or more and 150 g/L or less). Electrodeposition is preferably performed using a copper sulfate solution with a tungsten concentration of 5 mg/L or more and 20 mg/L or less (more preferably 10 mg/L or more and 20 mg/L or less). This electrodeposition is carried out at a liquid temperature of 20°C or more and 50°C or less (more preferably 30°C or more and 50°C or less) and a current density of 10 A/ dm2 or more and 40 A/dm2 or less (more preferably 20 A/ dm2 or more and 40 A/dm2 or less) . (below) and an electrical quantity of 50 A·s to 200 A·s (more preferably 50 A·s to 150 A·s). In particular, in the first step plating process, fine vertically shaped roughened particles are treated by using a copper sulfate solution that has a lower copper concentration than conventional methods and contains inorganic additives within the above concentration range. It becomes easier to form on the surface. In the second plating step, the copper concentration is 40 g/L or more and 70 g/L or less (more preferably 50 g/L or more and 70 g/L or less), and the sulfuric acid concentration is 100 g/L or more and 300 g/L or less (more preferably 150 g/L). Electrodeposition is preferably performed using a copper sulfate solution (250 g/L or less). This electrodeposition is performed at a liquid temperature of 30°C or more and 60°C or less (more preferably 40°C or more and 50°C or less) and a current density of 10 A/ dm2 or more and 40 A/dm2 or less (more preferably 20 A/dm2 or more and 40 A/dm2 or less) . (below), and the plating conditions are preferably 10 A·s or more and 250 A·s or less (more preferably 10 A·s or more and 150 A·s or less). By going through such a plating step, roughened particles convenient for satisfying the above-mentioned surface parameters can be easily formed on the treated surface.
　所望により、粗化処理銅箔は防錆処理が施され、防錆処理層が形成されたものであってもよい。防錆処理は、亜鉛を用いためっき処理を含むのが好ましい。亜鉛を用いためっき処理は、亜鉛めっき処理及び亜鉛合金めっき処理のいずれであってもよく、亜鉛合金めっき処理は亜鉛－ニッケル合金処理が特に好ましい。亜鉛－ニッケル合金処理は少なくともＮｉ及びＺｎを含むめっき処理であればよく、Ｓｎ、Ｃｒ、Ｃｏ等の他の元素をさらに含んでいてもよい。亜鉛－ニッケル合金めっきにおけるＮｉ／Ｚｎ付着比率は、質量比で、１．２以上１０以下が好ましく、より好ましくは２以上７以下、さらに好ましくは２．７以上４以下である。また、防錆処理はクロメート処理をさらに含むのが好ましく、このクロメート処理は亜鉛を用いためっき処理の後に、亜鉛を含むめっきの表面に行われるのがより好ましい。こうすることで防錆性をさらに向上させることができる。特に好ましい防錆処理は、亜鉛－ニッケル合金めっき処理とその後のクロメート処理との組合せである。 If desired, the roughened copper foil may be subjected to rust prevention treatment and may have a rust prevention treatment layer formed thereon. Preferably, the rust prevention treatment includes plating treatment using zinc. The plating treatment using zinc may be either a zinc plating treatment or a zinc alloy plating treatment, and the zinc alloy plating treatment is particularly preferably a zinc-nickel alloy treatment. The zinc-nickel alloy treatment may be a plating treatment that contains at least Ni and Zn, and may further contain other elements such as Sn, Cr, and Co. The Ni/Zn adhesion ratio in zinc-nickel alloy plating is preferably 1.2 or more and 10 or less, more preferably 2 or more and 7 or less, and even more preferably 2.7 or more and 4 or less, in terms of mass ratio. Moreover, it is preferable that the rust prevention treatment further includes chromate treatment, and it is more preferable that this chromate treatment is performed on the surface of the plating containing zinc after the plating treatment using zinc. By doing so, the rust prevention properties can be further improved. A particularly preferred anticorrosion treatment is a combination of zinc-nickel alloy plating treatment followed by chromate treatment.
　所望により、粗化処理銅箔は表面にシランカップリング剤処理が施され、シランカップリング剤層が形成されたものであってもよい。これにより耐湿性、耐薬品性及び接着剤等との密着性等を向上することができる。シランカップリング剤層は、シランカップリング剤を適宜希釈して塗布し、乾燥させることにより形成することができる。シランカップリング剤の例としては、４－グリシジルブチルトリメトキシシラン、３－グリシドキシプロピルトリメトキシシラン等のエポキシ官能性シランカップリング剤、又は３－アミノプロピルトリメトキシシラン、Ｎ－（２－アミノエチル）－３－アミノプロピルトリメトキシシラン、Ｎ－３－（４－（３－アミノプロポキシ）ブトキシ）プロピル－３－アミノプロピルトリメトキシシラン、Ｎ－フェニル－３－アミノプロピルトリメトキシシラン等のアミノ官能性シランカップリング剤、又は３－メルカプトプロピルトリメトキシシラン等のメルカプト官能性シランカップリング剤又はビニルトリメトキシシラン、ビニルフェニルトリメトキシシラン等のオレフィン官能性シランカップリング剤、又は３－メタクリロキシプロピルトリメトキシシラン等のアクリル官能性シランカップリング剤、又はイミダゾールシラン等のイミダゾール官能性シランカップリング剤、又はトリアジンシラン等のトリアジン官能性シランカップリング剤等が挙げられる。 If desired, the surface of the roughened copper foil may be treated with a silane coupling agent to form a silane coupling agent layer. This makes it possible to improve moisture resistance, chemical resistance, adhesion to adhesives, and the like. The silane coupling agent layer can be formed by appropriately diluting a silane coupling agent, applying it, and drying it. Examples of silane coupling agents include epoxy-functional silane coupling agents such as 4-glycidylbutyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-aminopropyltrimethoxysilane, N-(2- aminoethyl)-3-aminopropyltrimethoxysilane, N-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, etc. Amino-functional silane coupling agents, or mercapto-functional silane coupling agents such as 3-mercaptopropyltrimethoxysilane, or olefin-functional silane coupling agents such as vinyltrimethoxysilane, vinylphenyltrimethoxysilane, or 3-methacrylic Examples include acrylic-functional silane coupling agents such as roxypropyltrimethoxysilane, or imidazole-functional silane coupling agents such as imidazole silane, or triazine-functional silane coupling agents such as triazine silane.
　上述した理由から、粗化処理銅箔は、粗化処理面に防錆処理層及び／又はシランカップリング剤層をさらに備えることが好ましく、より好ましくは防錆処理層及びシランカップリング剤層の両方を備える。粗化処理面に防錆処理層及び／又はシランカップリング剤層が形成されている場合、本明細書における粗化処理面の各種パラメータの数値は、防錆処理層及び／又はシランカップリング剤処理層が形成された後の粗化処理銅箔を測定及び解析して得られる数値を意味するものとする。防錆処理層及びシランカップリング剤層は、粗化処理銅箔の粗化処理面側のみならず、粗化処理面が形成されていない側に形成されてもよい。 For the reasons mentioned above, it is preferable that the roughened copper foil further includes a rust prevention treatment layer and/or a silane coupling agent layer on the roughening treatment surface, and more preferably, a rust prevention treatment layer and/or a silane coupling agent layer. Have both. When a rust prevention treatment layer and/or a silane coupling agent layer are formed on the roughening treatment surface, the numerical values of various parameters of the roughening treatment surface in this specification are based on the rust prevention treatment layer and/or the silane coupling agent layer. It means the numerical value obtained by measuring and analyzing the roughened copper foil after the treatment layer has been formed. The rust prevention layer and the silane coupling agent layer may be formed not only on the roughened surface side of the roughened copper foil but also on the side where the roughened surface is not formed.
　キャリア付銅箔
　上述したように、本発明の粗化処理銅箔はキャリア付銅箔の形態で提供されてもよい。すなわち、本発明の好ましい態様によれば、キャリアと、キャリア上に設けられた剥離層と、剥離層上に粗化処理面を外側にして設けられた上記粗化処理銅箔とを備えた、キャリア付銅箔が提供される。もっとも、キャリア付銅箔は、本発明の粗化処理銅箔を用いること以外は、公知の層構成が採用可能である。 Copper Foil with Carrier As mentioned above, the roughened copper foil of the present invention may be provided in the form of a copper foil with a carrier. That is, according to a preferred embodiment of the present invention, the method includes a carrier, a release layer provided on the carrier, and the roughened copper foil provided on the release layer with the roughened surface facing outward. A copper foil with a carrier is provided. However, the carrier-attached copper foil may have any known layer structure, except for using the roughened copper foil of the present invention.
　キャリアは、粗化処理銅箔を支持してそのハンドリング性を向上させるための支持体であり、典型的なキャリアは金属層を含む。このようなキャリアの例としては、アルミニウム箔、銅箔、ステンレス（ＳＵＳ）箔、表面を銅等でメタルコーティングした樹脂フィルムやガラス等が挙げられ、好ましくは、銅箔である。銅箔は圧延銅箔及び電解銅箔のいずれであってもよいが、好ましくは電解銅箔である。キャリアの厚さは典型的には２５０μｍ以下であり、好ましくは９μｍ以上２００μｍ以下である。 The carrier is a support for supporting the roughened copper foil to improve its handling properties, and a typical carrier includes a metal layer. Examples of such carriers include aluminum foil, copper foil, stainless steel (SUS) foil, resin films whose surfaces are metal-coated with copper or the like, glass, and the like, with copper foil being preferred. The copper foil may be either a rolled copper foil or an electrolytic copper foil, but preferably an electrolytic copper foil. The thickness of the carrier is typically 250 μm or less, preferably 9 μm or more and 200 μm or less.
　剥離層は、キャリアの引き剥がし強度を弱くし、該強度の安定性を担保し、さらには高温でのプレス成形時にキャリアと銅箔の間で起こりうる相互拡散を抑制する機能を有する層である。剥離層は、キャリアの一方の面に形成されるのが一般的であるが、両面に形成されてもよい。剥離層は、有機剥離層及び無機剥離層のいずれであってもよい。有機剥離層に用いられる有機成分の例としては、窒素含有有機化合物、硫黄含有有機化合物、カルボン酸等が挙げられる。窒素含有有機化合物の例としては、トリアゾール化合物、イミダゾール化合物等が挙げられ、中でもトリアゾール化合物は剥離性が安定し易い点で好ましい。トリアゾール化合物の例としては、１，２，３－ベンゾトリアゾール、カルボキシベンゾトリアゾール、Ｎ’，Ｎ’－ビス（ベンゾトリアゾリルメチル）ユリア、１Ｈ－１，２，４－トリアゾール及び３－アミノ－１Ｈ－１，２，４－トリアゾール等が挙げられる。硫黄含有有機化合物の例としては、メルカプトベンゾチアゾール、チオシアヌル酸、２－ベンズイミダゾールチオール等が挙げられる。カルボン酸の例としては、モノカルボン酸、ジカルボン酸等が挙げられる。一方、無機剥離層に用いられる無機成分の例としては、Ｎｉ、Ｍｏ、Ｃｏ、Ｃｒ、Ｆｅ、Ｔｉ、Ｗ、Ｐ、Ｚｎ、クロメート処理膜等が挙げられる。なお、剥離層の形成はキャリアの少なくとも一方の表面に剥離層成分含有溶液を接触させ、剥離層成分をキャリアの表面に固定させること等により行えばよい。キャリアを剥離層成分含有溶液に接触させる場合、この接触は、剥離層成分含有溶液への浸漬、剥離層成分含有溶液の噴霧、剥離層成分含有溶液の流下等により行えばよい。その他、蒸着やスパッタリング等による気相法で剥離層成分を被膜形成する方法も採用可能である。また、剥離層成分のキャリア表面への固定は、剥離層成分含有溶液の吸着や乾燥、剥離層成分含有溶液中の剥離層成分の電着等により行えばよい。剥離層の厚さは、典型的には１ｎｍ以上１μｍ以下であり、好ましくは５ｎｍ以上５００ｎｍ以下である。 The peeling layer is a layer that has the function of weakening the peeling strength of the carrier, ensuring the stability of this strength, and further suppressing mutual diffusion that may occur between the carrier and the copper foil during press molding at high temperatures. . Although the release layer is generally formed on one side of the carrier, it may be formed on both sides. The release layer may be either an organic release layer or an inorganic release layer. Examples of organic components used in the organic release layer include nitrogen-containing organic compounds, sulfur-containing organic compounds, carboxylic acids, and the like. Examples of the nitrogen-containing organic compound include triazole compounds, imidazole compounds, etc. Among them, triazole compounds are preferred because they have easy releasability. Examples of triazole compounds include 1,2,3-benzotriazole, carboxybenzotriazole, N',N'-bis(benzotriazolylmethyl)urea, 1H-1,2,4-triazole and 3-amino- Examples include 1H-1,2,4-triazole. Examples of sulfur-containing organic compounds include mercaptobenzothiazole, thiocyanuric acid, 2-benzimidazolethiol, and the like. Examples of carboxylic acids include monocarboxylic acids, dicarboxylic acids, and the like. On the other hand, examples of inorganic components used in the inorganic release layer include Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, and a chromate-treated film. The release layer may be formed by, for example, bringing a release layer component-containing solution into contact with at least one surface of the carrier to fix the release layer component on the surface of the carrier. When the carrier is brought into contact with the release layer component-containing solution, this contact may be carried out by dipping the carrier in the release layer component-containing solution, spraying the release layer component-containing solution, flowing down the release layer component-containing solution, or the like. In addition, it is also possible to adopt a method of forming a film with the release layer component by a vapor phase method such as vapor deposition or sputtering. Further, the release layer component may be fixed to the carrier surface by adsorption or drying of a solution containing the release layer component, or by electrodeposition of the release layer component in the solution containing the release layer component. The thickness of the release layer is typically 1 nm or more and 1 μm or less, preferably 5 nm or more and 500 nm or less.
　所望により、剥離層とキャリア及び／又は粗化処理銅箔の間に他の機能層を設けてもよい。そのような他の機能層の例としては補助金属層が挙げられる。補助金属層はニッケル及び／又はコバルトからなるのが好ましい。このような補助金属層をキャリアの表面側及び／又は粗化処理銅箔の表面側に形成することで、高温又は長時間の熱間プレス成形時にキャリアと粗化処理銅箔の間で起こりうる相互拡散を抑制し、キャリアの引き剥がし強度の安定性を担保することができる。補助金属層の厚さは、０．００１μｍ以上３μｍ以下とするのが好ましい。 If desired, other functional layers may be provided between the release layer and the carrier and/or the roughened copper foil. Examples of such other functional layers include auxiliary metal layers. Preferably, the auxiliary metal layer consists of nickel and/or cobalt. By forming such an auxiliary metal layer on the surface side of the carrier and/or the surface side of the roughened copper foil, it is possible to reduce the risk of problems occurring between the carrier and the roughened copper foil during hot press forming at high temperatures or for long periods of time. Mutual diffusion can be suppressed and the stability of carrier peel strength can be ensured. The thickness of the auxiliary metal layer is preferably 0.001 μm or more and 3 μm or less.
　銅張積層板
　本発明の粗化処理銅箔はプリント配線板用銅張積層板の作製に用いられるのが好ましい。すなわち、本発明の好ましい態様によれば、上記粗化処理銅箔を備えた銅張積層板が提供される。本発明の粗化処理銅箔を用いることで、銅張積層板の加工において、熱可塑性樹脂基材との高い密着性と優れた高周波特性とを両立することができる。この銅張積層板は、本発明の粗化処理銅箔と、粗化処理銅箔の粗化処理面に密着して設けられる樹脂層とを備えてなる。粗化処理銅箔は樹脂層の片面に設けられてもよいし、両面に設けられてもよい。樹脂層は、樹脂、好ましくは絶縁性樹脂を含んでなる。樹脂層はプリプレグ及び／又は樹脂シートであるのが好ましい。プリプレグとは、合成樹脂板、ガラス板、ガラス織布、ガラス不織布、紙等の基材に合成樹脂を含浸させた複合材料の総称である。また、樹脂層には絶縁性を向上する等の観点からシリカ、アルミナ等の各種無機粒子からなるフィラー粒子等が含有されていてもよい。樹脂層の厚さは特に限定されないが、１μｍ以上１０００μｍ以下が好ましく、より好ましくは２μｍ以上４００μｍ以下であり、さらに好ましくは３μｍ以上２００μｍ以下である。樹脂層は複数の層で構成されていてよい。プリプレグ及び／又は樹脂シート等の樹脂層は予め銅箔表面に塗布されるプライマー樹脂層を介して粗化処理銅箔に設けられていてもよい。 Copper-clad laminate The roughened copper foil of the present invention is preferably used for producing 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 roughened copper foil is provided. By using the roughened copper foil of the present invention, it is possible to achieve both high adhesion to the thermoplastic resin base material and excellent high frequency characteristics in the processing of copper-clad laminates. This copper-clad laminate includes the roughened copper foil of the present invention and a resin layer provided in close contact with the roughened surface of the roughened copper foil. The roughened copper foil may be provided on one side or both sides of the resin layer. The resin layer contains a resin, preferably an insulating resin. Preferably, the resin layer is a prepreg and/or a resin sheet. Prepreg is a general term for composite materials in which a base material such as a synthetic resin plate, glass plate, glass woven fabric, glass nonwoven fabric, or paper is impregnated with synthetic resin. Further, the resin layer may contain filler particles made of various inorganic particles such as silica and alumina from the viewpoint of improving insulation properties. 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 still 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 roughened copper foil via a primer resin layer that is previously applied to the surface of the copper foil.
　高周波用途に適した銅張積層板を提供する観点から、樹脂層は熱可塑性樹脂を含むのが好ましく、より好ましくは、樹脂層に含まれる樹脂成分の大半（例えば５０重量％以上）又は殆ど（例えば８０重量％以上若しくは９０重量％以上）が熱可塑性樹脂である。熱可塑性樹脂の好ましい例としては、ポリサルフォン（ＰＳＦ）、ポリエーテルサルフォン（ＰＥＳ）、非晶ポリアリレート（ＰＡＲ）、液晶ポリマー（ＬＣＰ）、ポリエーテルエーテルケトン（ＰＥＥＫ）、熱可塑性ポリイミド（ＰＩ）、ポリアミドイミド（ＰＡＩ）、フッ素樹脂、ポリアミド（ＰＡ）、ナイロン、ポリアセタール（ＰＯＭ）、変性ポリフェニレンエーテル（ｍ－ＰＰＥ）、ポリエチレンテレフタレート（ＰＥＴ）、グラスファイバー強化ポリエチレンテレフタレート（ＧＦ－ＰＥＴ）、シクロオレフィン（ＣＯＰ）、及びこれらの任意の組合せが挙げられる。望ましい誘電正接及び優れた耐熱性の観点から、熱可塑性樹脂のより好ましい例としては、ポリサルフォン（ＰＳＦ）、ポリエーテルサルフォン（ＰＥＳ）、非晶ポリアリレート（ＰＡＲ）、液晶ポリマー（ＬＣＰ）、ポリエーテルエーテルケトン（ＰＥＥＫ）、熱可塑性ポリイミド（ＰＩ）、ポリアミドイミド（ＰＡＩ）、フッ素樹脂、及びそれらの任意の組合せが挙げられる。低誘電率の観点から、特に好ましい熱可塑性樹脂は液晶ポリマー（ＬＣＰ）及び／又はフッ素樹脂である。フッ素樹脂の好ましい例としては、ポリテトラフルオロエチレン（ＰＴＦＥ）、テトラフルオロエチレン・パーフルオロアルキルビニルエーテル共重合体（ＰＦＡ）、テトラフルオロエチレン・ヘキサフルオロプロピレン共重合体（ＦＥＰ）、テトラフルオロエチレン－エチレン共重合体（ＥＴＦＥ）、及びそれらの任意の組合せが挙げられる。なお、絶縁樹脂基材の粗化処理銅箔への貼り付けは、加熱しながらプレスすることにより行うのが好ましく、こうすることで熱可塑性樹脂を軟化させて粗化処理面の微細凹凸に入り込ませることができる。その結果、微細凹凸（特に縦長状の粗化粒子）の樹脂への食い込みによるアンカー効果により、銅箔と樹脂との密着性を確保することができる。 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 most (for example, 50% by weight or more) or most ( For example, 80% by weight or more or 90% by weight or more) is thermoplastic resin. Preferred examples of thermoplastic resins include polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), and 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 preferable examples of thermoplastic resins include polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), and polysulfone. Examples include etheretherketone (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 polymers (LCP) and/or fluororesins. Preferred examples of the fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene. copolymers (ETFE), and any combination thereof. It should be noted that it is preferable to attach the insulating resin base material to the roughened copper foil by pressing while heating.This softens the thermoplastic resin and allows it to penetrate into the fine irregularities of the roughened surface. can be set. As a result, the adhesion between the copper foil and the resin can be ensured due to the anchor effect caused by the fine irregularities (particularly the vertically elongated roughened particles) biting into the resin.
　プリント配線板
　本発明の粗化処理銅箔はプリント配線板の作製に用いられるのが好ましい。すなわち、本発明の好ましい態様によれば、上記粗化処理銅箔を備えたプリント配線板が提供される。本発明の粗化処理銅箔を用いることで、プリント配線板の製造において、優れた高周波特性と高い回路密着性とを両立することができる。本態様によるプリント配線板は、樹脂層と、銅層とが積層された層構成を含んでなる。銅層は本発明の粗化処理銅箔に由来する層である。また、樹脂層については銅張積層板に関して上述したとおりである。いずれにしても、プリント配線板は、本発明の粗化処理銅箔を用いること以外は、公知の層構成が採用可能である。プリント配線板に関する具体例としては、プリプレグの片面又は両面に本発明の粗化処理銅箔を接着させ硬化した積層体とした上で回路形成した片面又は両面プリント配線板や、これらを多層化した多層プリント配線板等が挙げられる。また、他の具体例としては、樹脂フィルム上に本発明の粗化処理銅箔を形成して回路を形成するフレキシブルプリント配線板、ＣＯＦ、ＴＡＢテープ等も挙げられる。さらに他の具体例としては、本発明の粗化処理銅箔に上述の樹脂層を塗布した樹脂付銅箔（ＲＣＣ）を形成し、樹脂層を絶縁接着材層として上述のプリント基板に積層した後、粗化処理銅箔を配線層の全部又は一部としてモディファイド・セミ・アディティブ法（ＭＳＡＰ）、サブトラクティブ法等の手法で回路を形成したビルドアップ配線板や、粗化処理銅箔を除去してセミ・アディティブ法（ＳＡＰ）で回路を形成したビルドアップ配線板、半導体集積回路上へ樹脂付銅箔の積層と回路形成を交互に繰りかえすダイレクト・ビルドアップ・オン・ウェハー等が挙げられる。より発展的な具体例として、上記樹脂付銅箔を基材に積層し回路形成したアンテナ素子、接着剤層を介してガラスや樹脂フィルムに積層しパターンを形成したパネル・ディスプレイ用電子材料や窓ガラス用電子材料、本発明の粗化処理銅箔に導電性接着剤を塗布した電磁波シールド・フィルム等も挙げられる。とりわけ、本発明の粗化処理銅箔を備えたプリント配線板は、信号周波数１０ＧＨｚ以上の高周波帯域で用いられる自動車用アンテナ、携帯電話基地局アンテナ、高性能サーバー、衝突防止用レーダー等の用途で用いられる高周波基板として好適に用いられる。 Printed Wiring Board The roughened copper foil of the present invention is preferably used for producing printed wiring boards. That is, according to a preferred embodiment of the present invention, a printed wiring board including the roughened copper foil is provided. By using the roughened copper foil of the present invention, it is possible to achieve both excellent high frequency characteristics and high circuit adhesion in the manufacture of printed wiring boards. The printed wiring board according to this embodiment includes a layered structure in which a resin layer and a copper layer are laminated. The copper layer is a layer derived from the roughened copper foil of the present invention. Further, the resin layer is as described above regarding the copper-clad laminate. In any case, the printed wiring board may have a known layer structure, except for using the roughened copper foil of the present invention. Specific examples of printed wiring boards include single-sided or double-sided printed wiring boards in which the roughened copper foil of the present invention is adhered to one or both sides of prepreg to form a cured laminate, and circuits are formed on the cured laminate, and multilayered versions of these. Examples include multilayer printed wiring boards. Further, other specific examples include flexible printed wiring boards, COF, TAB tapes, etc. in which a circuit is formed by forming the roughened copper foil of the present invention on a resin film. As another specific example, a resin-coated copper foil (RCC) is formed by applying the above-mentioned resin layer to the roughened copper foil of the present invention, and the resin layer is laminated on the above-mentioned printed circuit board as an insulating adhesive layer. After that, build-up wiring boards in which circuits are formed using methods such as modified semi-additive method (MSAP) or subtractive method using the roughened copper foil as all or part of the wiring layer, and the roughened copper foil are removed. Examples include a build-up wiring board in which a circuit is formed using a semi-additive method (SAP), and a direct build-up on wafer in which lamination of resin-coated copper foil and circuit formation are alternately repeated on a semiconductor integrated circuit. More advanced examples include antenna elements in which the resin-coated copper foil is laminated onto a base material to form a circuit, electronic materials for panels and displays, and windows in which patterns are formed by laminating the resin-coated copper foil onto glass or resin film via an adhesive layer. Examples include electronic materials for glass, electromagnetic shielding films made by applying a conductive adhesive to the roughened copper foil of the present invention, and the like. In particular, printed wiring boards equipped with the roughened copper foil of the present invention can be used in applications such as automotive antennas, mobile phone base station antennas, high-performance servers, and collision prevention radars used in high frequency bands of signal frequencies of 10 GHz or higher. It is suitably used as a high frequency substrate.
　本発明を以下の例によってさらに具体的に説明する。 The present invention will be explained in more detail with reference to the following examples.
　例１～１１
　本発明の粗化処理銅箔の製造を以下のようにして行った。 Examples 1 to 11
The roughened copper foil of the present invention was manufactured as follows.
（１）電解銅箔の準備
　銅電解液として以下に示される組成の硫酸酸性硫酸銅溶液を用い、陰極に表面粗さＲａが０．２０μｍのチタン製の電極を用い、陽極にはＤＳＡ（寸法安定性陽極）を用いて、溶液温度４５℃、電流密度５５Ａ／ｄｍ２で電解し、厚さ１８μｍの電解銅箔を得た。
＜硫酸酸性硫酸銅溶液の組成＞
‐　銅濃度：８０ｇ／Ｌ
‐　硫酸濃度：２６０ｇ／Ｌ
‐　ビス（３－スルホプロピル）ジスルフィド濃度：３０ｍｇ／Ｌ
‐　ジアリルジメチルアンモニウムクロライド重合体濃度：５０ｍｇ／Ｌ
‐　塩素濃度：４０ｍｇ／Ｌ (1) Preparation of electrolytic copper foil A sulfuric acid copper sulfate solution with the composition shown below is used as the copper electrolyte, a titanium electrode with a surface roughness Ra of 0.20 μm is used as the cathode, and a DSA (dimensions: Using a stable anode), electrolysis was carried out at a solution temperature of 45° C. and a current density of 55 A/dm 2 to obtain an electrolytic copper foil with a thickness of 18 μm.
<Composition of sulfuric acid acidic copper sulfate solution>
- Copper concentration: 80g/L
- Sulfuric acid concentration: 260g/L
- Bis(3-sulfopropyl) disulfide concentration: 30mg/L
- Diallyldimethylammonium chloride polymer concentration: 50mg/L
- Chlorine concentration: 40mg/L
（２）粗化処理
　得られた電解銅箔の析出面に対して、粗化処理を行った。この粗化処理は、表１に示すとおり、例１～６及び８～１１については２段階の粗化処理（第一粗化処理及び第二粗化処理）とし、例７については１段階の粗化処理（第一粗化処理）とした。このとき、酸性硫酸銅溶液の組成、及び電着条件を表１に示されるように適宜変えることで、粗化処理表面の特徴が異なる様々なサンプルを作製した。 (2) Roughening treatment The deposition surface of the obtained electrolytic copper foil was subjected to a roughening treatment. As shown in Table 1, this roughening treatment is a two-stage roughening treatment (first roughening treatment and second roughening treatment) for Examples 1 to 6 and 8 to 11, and a one-stage roughening treatment for Example 7. A roughening treatment (first roughening treatment) was performed. At this time, by appropriately changing the composition of the acidic copper sulfate solution and the electrodeposition conditions as shown in Table 1, various samples with different characteristics of the roughened surface were prepared.
　具体的には、各段階における粗化処理の条件は以下のとおりとした。
‐　第一粗化処理では、表１に示されるＣｕ濃度、硫酸濃度及びＷ濃度となるように、硫酸、硫酸銅、及び所望により無機添加剤としてタングステン酸ナトリウム（例１～６、８及び９）を含む酸性硫酸銅溶液を用いて、表１に示される電着条件（液温、電流密度及び電気量）にて電気メッキを実施した。
‐　第二粗化処理では、表１に示されるＣｕ濃度及び硫酸濃度となるように、硫酸及び硫酸銅を含む酸性硫酸銅溶液を用いて、表１に示される電着条件（液温、電流密度及び電気量）にて電気メッキを実施した。 Specifically, the conditions for the roughening treatment at each stage were as follows.
- In the first roughening treatment, sulfuric acid, copper sulfate, and optionally sodium tungstate as an inorganic additive (Examples 1 to 6, 8, and 9 Electroplating was carried out using an acidic copper sulfate solution containing ) under the electrodeposition conditions (liquid temperature, current density, and quantity of electricity) shown in Table 1.
- In the second roughening treatment, an acidic copper sulfate solution containing sulfuric acid and copper sulfate was used under the electrodeposition conditions (liquid temperature, current Electroplating was carried out at the following density and electrical charge).
（３）防錆処理
　電解銅箔の粗化処理を行った面に、亜鉛－ニッケル合金めっき処理及びクロメート処理からなる防錆処理を行った。まず、亜鉛濃度１ｇ／Ｌ、ニッケル濃度２ｇ／Ｌ及びピロリン酸カリウム濃度８０ｇ／Ｌを含む溶液を用い、液温４０℃、電流密度０．５Ａ／ｄｍ２の条件で、亜鉛－ニッケル合金めっき処理を行った。次いで、クロム酸１ｇ／Ｌを含む水溶液を用い、ｐＨ１２、電流密度１Ａ／ｄｍ２の条件で、亜鉛－ニッケル合金めっき処理を行った表面にクロメート処理を行った。 (3) Rust prevention treatment The roughened surface of the electrolytic copper foil was subjected to rust prevention treatment consisting of zinc-nickel alloy plating treatment and chromate treatment. First, a zinc-nickel alloy plating treatment was performed using a solution containing a zinc concentration of 1 g/L, a nickel concentration of 2 g/L, and a potassium pyrophosphate concentration of 80 g/L under conditions of a liquid temperature of 40°C and a current density of 0.5 A/ dm2 . I did it. Next, the surface subjected to the zinc-nickel alloy plating treatment was subjected to chromate treatment using an aqueous solution containing 1 g/L of chromic acid under conditions of pH 12 and current density of 1 A/dm 2 .
（４）シランカップリング剤処理
　３－アミノプロピルトリメトキシシラン濃度が６ｇ／Ｌの水溶液を電解銅箔の粗化処理を行った面に吸着させ、電熱器により水分を蒸発させることにより、シランカップリング剤処理を行った。このとき、電解銅箔の粗化処理を行っていない面にはシランカップリング剤処理を行わなかった。 (4) Silane coupling agent treatment An aqueous solution of 3-aminopropyltrimethoxysilane with a concentration of 6 g/L is adsorbed on the roughened surface of the electrolytic copper foil, and the water is evaporated with an electric heater to form a silane cup. Ring agent treatment was performed. At this time, the silane coupling agent treatment was not performed on the surface of the electrolytic copper foil that had not been subjected to the roughening treatment.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　評価
　例１～１１で作製された粗化処理銅箔について、以下に示される各種評価を行った。 The roughened copper foils produced in Evaluation Examples 1 to 11 were subjected to various evaluations as shown below.
＜粗化処理面の表面性状パラメータ＞
　レーザー顕微鏡を用いた表面粗さ解析により、粗化処理銅箔の粗化処理面の測定をＪＩＳ　Ｂ０６８１－２：２０１８に準拠して行った。具体的な測定条件は表２に示されるとおりとした。得られた粗化処理面の表面プロファイルに対して、表２に示される条件に従って解析を行い、Ｓｓｋ、Ｓｋｕ、Ｓｍｒ１、Ｖｍｐ及びＶｍｃを算出するとともに、Ｖｍｐ及びＶｍｃの和（＝Ｖｍｐ＋Ｖｍｃ）を粗化粒子の体積として求めた。各例につき上記パラメータの算出を異なる１０視野にて実施し、全視野における平均値を当該サンプルにおける粗化処理面の表面性状パラメータとしてそれぞれ採用した。結果は表３に示されるとおりであった。 <Surface quality parameters of roughened surface>
The roughened surface of the roughened copper foil was measured by surface roughness analysis using a laser microscope in accordance with JIS B0681-2:2018. The specific measurement conditions were as shown in Table 2. The surface profile of the obtained roughened surface was analyzed according to the conditions shown in Table 2, and Ssk, Sku, Smr1, Vmp and Vmc were calculated, and the sum of Vmp and Vmc (=Vmp+Vmc) was roughened. It was determined as the volume of the particle. For each example, the above parameters were calculated in 10 different visual fields, and the average value in all the visual fields was adopted as the surface texture parameter of the roughened surface of the sample. The results were as shown in Table 3.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
＜熱可塑性樹脂（液晶ポリマー）に対する剥離強度＞
　熱可塑性樹脂基材として液晶ポリマー（ＬＣＰ）フィルム（株式会社クラレ製、ベクスターＣＴ－Ｑ、厚さ５０μｍ×１枚）を用意した。この熱可塑性樹脂基材に、得られた粗化処理銅箔をその粗化処理面が樹脂基材と当接するように積層し、真空プレス機を使用して、プレス圧４ＭＰａ、温度３３０℃、プレス時間１０分の条件でプレスを行い、銅張積層板を作製した。この銅張積層板に対して、塩化第二銅エッチング液を用いて、サブトラクティブ法による回路形成を行い、３ｍｍ幅の直線回路を備えた試験基板を作製した。作製した試験基板に対して、卓上型精密万能試験機（株式会社島津製作所製、ＡＧＳ－５０ＮＸ）を用いて、形成した直線回路をＪＩＳ　Ｃ　５０１６－１９９４のＡ法（９０°剥離）に準拠して熱可塑性樹脂基材から引き剥がして、常態剥離強度（ｋｇｆ／ｃｍ）を測定した。この剥離強度が０．６０ｋｇｆ／ｃｍ以上である場合に合格と判定した。結果は表３に示されるとおりであった。 <Peel strength against thermoplastic resin (liquid crystal polymer)>
A liquid crystal polymer (LCP) film (manufactured by Kuraray Co., Ltd., Vector CT-Q, thickness 50 μm x 1 sheet) was prepared as a thermoplastic resin base material. The obtained roughened copper foil was laminated on this thermoplastic resin base material so that its roughened surface was in contact with the resin base material, and using a vacuum press machine, press pressure was 4 MPa, temperature was 330°C, Pressing was performed under conditions of a pressing time of 10 minutes to produce a copper-clad laminate. A circuit was formed on this copper-clad laminate by a subtractive method using a cupric chloride etching solution to produce a test board having a linear circuit with a width of 3 mm. The formed test board was tested using a tabletop precision universal testing machine (AGS-50NX, manufactured by Shimadzu Corporation) in accordance with JIS C 5016-1994 method A (90° peeling). The film was peeled off from the thermoplastic resin base material to measure normal peel strength (kgf/cm). When this peel strength was 0.60 kgf/cm or more, it was determined to be acceptable. The results were as shown in Table 3.
＜伝送特性の評価＞
　絶縁樹脂基材として高周波用基材（パナソニック株式会社製、ＭＥＧＴＲＯＮ６Ｎ、厚さ４５μｍ×２枚）を用意した。この絶縁樹脂基材の両面に得られた粗化処理銅箔をその粗化処理面が絶縁樹脂基材と当接するように積層し、真空プレス機を使用して、プレス圧３ＭＰａ、温度１９０℃、プレス時間９０分の条件でプレスを行い、銅張積層板を得た。その後、銅張積層板に対して、塩化第二銅エッチング液を用いて、サブトラクティブ法による回路形成（回路高さ：１８μｍ、回路幅３００μｍ、回路長：３００ｍｍ）を行った。こうして、特性インピーダンスが５０Ω±２Ωになるようマイクロストリップラインを形成した伝送損失測定用基板を得た。得られた伝送損失測定用基板に対して、ネットワークアナライザー（キーサイト・テクノロジー社製、Ｎ５２２５Ｂ）を用いて、以下の設定条件で測定を行い、５０ＧＨｚにおける伝送損失Ｌ１（ｄＢ）を計測した。そして、例７（比較例）の５０ＧＨｚにおける伝送損失Ｌ０（ｄＢ）に対する、伝送損失Ｌ１の増加率（＝Ｌ１／Ｌ０）を算出した。この伝送損失増加率が１．１０以下である場合に合格と判定した。結果は表３に示されるとおりであった。
（設定条件）
‐ＩＦ　Ｂａｎｄｗｉｄｔｈ：１００Ｈｚ
‐Ｆｒｅｑｕｅｎｃｙ：１０ＭＨｚ～５０ＧＨｚ
‐Ｄａｔａ　ｐｏｉｎｔｓ：５０１ｐｏｉｎｔ
‐Ａｖｅｒａｇｅ：Ｏｆｆ
‐校正方法：ＳＯＬＴ（ｅ－ｃａｌ） <Evaluation of transmission characteristics>
High-frequency base materials (MEGTRON6N, manufactured by Panasonic Corporation, 45 μm thick x 2 sheets) were prepared as insulating resin base materials. The obtained roughened copper foil was laminated on both sides of this insulating resin base material so that the roughened surface was in contact with the insulating resin base material, and a vacuum press was used to press the foil at a pressure of 3 MPa and a temperature of 190°C. Pressing was performed under the conditions of 90 minutes of pressing time to obtain a copper-clad laminate. Thereafter, a circuit was formed on the copper-clad laminate by a subtractive method (circuit height: 18 μm, circuit width: 300 μm, circuit length: 300 mm) using a cupric chloride etching solution. In this way, a substrate for transmission loss measurement was obtained in which a microstrip line was formed so that the characteristic impedance was 50Ω±2Ω. The obtained transmission loss measurement board was measured using a network analyzer (manufactured by Keysight Technologies, N5225B) under the following setting conditions, and the transmission loss L 1 (dB) at 50 GHz was measured. Then, the rate of increase in transmission loss L 1 (=L 1 /L 0 ) with respect to transmission loss L 0 (dB) at 50 GHz in Example 7 (comparative example) was calculated. When this transmission loss increase rate was 1.10 or less, it was determined to be acceptable. The results were as shown in Table 3.
(Setting conditions)
-IF Bandwidth: 100Hz
-Frequency: 10MHz to 50GHz
-Data points: 501 points
-Average: Off
-Calibration method: SOLT (e-cal)
Figure JPOXMLDOC01-appb-T000003
 
Figure JPOXMLDOC01-appb-T000003
 

Claims (7)

  1. 　少なくとも一方の側に粗化処理面を有する粗化処理銅箔であって、
    　前記粗化処理面は、スキューネスＳｓｋが０．３５より大きく、かつ、突出山部の実体体積Ｖｍｐ及びコア部の実体体積Ｖｍｃの和であるＶｍｐ＋Ｖｍｃが０．１０μｍ３／μｍ２以上０．２８μｍ３／μｍ２以下であり、
    　前記Ｓｓｋは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルターによるカットオフを行わず、Ｌフィルターによるカットオフ波長１．０μｍの条件で測定される値であり、
    　前記Ｖｍｐ及びＶｍｃは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルター及びＬフィルターによるカットオフを行わない条件で測定される値である、粗化処理銅箔。     A roughened copper foil having a roughened surface on at least one side,
    The roughened surface has a skewness Ssk greater than 0.35, and Vmp+Vmc, which is the sum of the substantial volume Vmp of the protruding peak portion and the substantial volume Vmc of the core portion, is 0.10 μm 3 /μm 2 or more and 0.28 μm 3 / μm2 or less,
    The Ssk is a value measured in accordance with JIS B0681-2:2018 without cutoff with an S filter and with a cutoff wavelength of 1.0 μm using an L filter,
    The above-mentioned Vmp and Vmc are values measured in accordance with JIS B0681-2:2018 without cutoff using an S filter and an L filter, and are roughened copper foils.
  2. 　前記粗化処理面は、クルトシスＳｋｕが２．７０以上４．９０以下であり、
    　前記Ｓｋｕは、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルター及びＬフィルターによるカットオフを行わない条件で測定される値である、請求項１に記載の粗化処理銅箔。     The roughened surface has a kurtosis Sku of 2.70 or more and 4.90 or less,
    The roughened copper foil according to claim 1, wherein the Sku is a value measured in accordance with JIS B0681-2:2018 without cutoff by an S filter and an L filter.
  3. 　前記粗化処理面は、突出山部とコア部を分離する負荷面積率Ｓｍｒ１が１１．２％以上であり、
    　前記Ｓｍｒ１は、ＪＩＳ　Ｂ０６８１－２：２０１８に準拠してＳフィルターによるカットオフを行わず、Ｌフィルターによるカットオフ波長１．０μｍの条件で測定される値である、請求項１又は２に記載の粗化処理銅箔。     The roughened surface has a load area ratio Smr1 of 11.2% or more that separates the protruding peak portion and the core portion,
    The Smr1 according to claim 1 or 2 is a value measured under conditions of a cutoff wavelength of 1.0 μm using an L filter and no cutoff using an S filter in accordance with JIS B0681-2:2018. Roughened copper foil.
  4. 　前記粗化処理面に防錆処理層及び／又はシランカップリング剤層をさらに備えた、請求項１又は２に記載の粗化処理銅箔。 The roughened copper foil according to claim 1 or 2, further comprising a rust prevention treatment layer and/or a silane coupling agent layer on the roughened surface.
  5. 　キャリアと、該キャリア上に設けられた剥離層と、該剥離層上に前記粗化処理面を外側にして設けられた請求項１又は２に記載の粗化処理銅箔とを備えた、キャリア付銅箔。 A carrier comprising a carrier, a release layer provided on the carrier, and the roughened copper foil according to claim 1 or 2, provided on the release layer with the roughened surface facing outward. With copper foil.
  6. 　請求項１又は２に記載の粗化処理銅箔を備えた、銅張積層板。 A copper-clad laminate comprising the roughened copper foil according to claim 1 or 2.
  7. 　請求項１又は２に記載の粗化処理銅箔を備えた、プリント配線板。 A printed wiring board comprising the roughened copper foil according to claim 1 or 2.
PCT/JP2023/010436 2022-03-24 2023-03-16 Roughened copper foil, copper foil with carrier, copper-clad laminate, and printed wiring board WO2023182174A1 (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011219790A (en) * 2010-04-06 2011-11-04 Fukuda Metal Foil & Powder Co Ltd Treated copper foil for copper-clad laminated board and copper-clad laminated board obtained by adhering the treated copper foil onto insulating resin substrate, and printed circuit board using the copper-clad laminated board
JP2011219789A (en) * 2010-04-06 2011-11-04 Fukuda Metal Foil & Powder Co Ltd Treated copper foil for copper-clad laminate, copper-clad laminate obtained by sticking the treated copper foil to insulating resin substrate, and printed wiring board obtained by using the copper-clad laminate
JP2013199082A (en) * 2012-03-26 2013-10-03 Jx Nippon Mining & Metals Corp Copper foil with carrier, method of manufacturing the same, copper foil with carrier for printed wiring board, and printed wiring board
WO2021193246A1 (en) * 2020-03-23 2021-09-30 三井金属鉱業株式会社 Roughened copper foil, copper-cladded laminate board, and printed wiring board
WO2022255420A1 (en) * 2021-06-03 2022-12-08 三井金属鉱業株式会社 Roughened copper foil, copper-clad laminated board, and printed wiring board

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011219790A (en) * 2010-04-06 2011-11-04 Fukuda Metal Foil & Powder Co Ltd Treated copper foil for copper-clad laminated board and copper-clad laminated board obtained by adhering the treated copper foil onto insulating resin substrate, and printed circuit board using the copper-clad laminated board
JP2011219789A (en) * 2010-04-06 2011-11-04 Fukuda Metal Foil & Powder Co Ltd Treated copper foil for copper-clad laminate, copper-clad laminate obtained by sticking the treated copper foil to insulating resin substrate, and printed wiring board obtained by using the copper-clad laminate
JP2013199082A (en) * 2012-03-26 2013-10-03 Jx Nippon Mining & Metals Corp Copper foil with carrier, method of manufacturing the same, copper foil with carrier for printed wiring board, and printed wiring board
WO2021193246A1 (en) * 2020-03-23 2021-09-30 三井金属鉱業株式会社 Roughened copper foil, copper-cladded laminate board, and printed wiring board
WO2022255420A1 (en) * 2021-06-03 2022-12-08 三井金属鉱業株式会社 Roughened copper foil, copper-clad laminated board, and printed wiring board

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