Laminate and method for manufacturing correless substrate

Abstract

A laminate (10) has a core resin layer (11), a first metal layer (12) provided on at least one surface side of the core resin layer (11) and provided with a peeling means, a diffusion prevention layer (13) provided on the surface of the first metal layer (12) on the opposite side from the core resin layer (11), and an anti-plating layer (14) provided on the surface of the diffusion prevention layer (13) on the opposite side from the first metal layer (12). A protective plating layer (15) may be provided in a region where the anti-plating layer (14) is not provided on the side of the anti-diffusion layer (13) opposite the first metal layer (12).

Description

Technical Field

[0001] The present invention relates to a laminate having a first metal layer provided on at least one surface side of a core resin layer and equipped with a peeling unit, and a method for producing a coreless substrate using the laminate. Background Art

[0002] In recent years, semiconductor packages widely used in electronic devices, communication devices, personal computers, etc. have been increasingly becoming more functional and miniaturized. In response to this, printed wiring boards and semiconductor element mounting package substrates in semiconductor packages are required to be thinner. As thinner printed wiring boards and semiconductor element mounting package substrates, for example, a so-called coreless substrate is known in which a first metal layer having a peeling unit, an insulating layer, and a wiring conductor are stacked on a core resin layer to form a wiring substrate, and then the core resin layer is peeled off from the wiring substrate (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. WO2020 / 121652 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] However, it is difficult to control the removal of the first metal layer remaining on the wiring substrate by etching after the core resin layer is separated from such a coreless substrate, and there may be problems such as over-etching or, conversely, insufficient etching. In addition, when it is desired to form a protective plating layer on the first metal layer and form a wiring conductor thereon, there is also a problem of corrosion of the protective plating layer due to mutual diffusion of constituent elements of the first metal layer and the protective plating layer.

[0008] The present invention has been made based on the above problems, and an object of the present invention is to provide a method for producing a laminate and a coreless substrate in which the first metal layer can be easily removed after the core resin layer is separated and a good protective plating layer can be formed.

[0009] Solutions for solving problems

[0010] The present invention is as follows. [1]

[0012] A laminated body comprising:

[0013] Core resin layer,

[0014] a first metal layer provided on at least one surface side of the core resin layer and having a peeling unit, and a diffusion prevention layer provided on a surface of the first metal layer opposite to the core resin layer. [2]

[0016] The laminated body according to [1], wherein a plating resist is provided on a surface of the diffusion prevention layer opposite to the first metal layer. [3]

[0018] The laminated body according to [2], wherein a protective plating layer is provided in a region of the diffusion prevention layer on the side opposite to the first metal layer where the plating resist is not provided. [4]

[0020] The laminate according to [1], wherein the diffusion prevention layer and the plating resist are provided on a surface of the first metal layer opposite to the core resin layer. [5]

[0022] The laminated body according to [4], further comprising a protective plating layer on the side of the diffusion prevention layer opposite to the first metal layer. [6]

[0024] The laminate according to [1], wherein the diffusion prevention layer includes at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium. [7]

[0026] The laminate according to [1], wherein a thickness of the first metal layer from an end surface on the diffusion prevention layer side to the peeling unit is 6 μm or more. [8]

[0028] A method for manufacturing a coreless substrate, comprising:

[0029] a support body preparation step of preparing a support body having a core resin layer and a first metal layer provided on at least one side of the core resin layer and having a peeling unit, and

[0030] The diffusion prevention layer forming step is to form a diffusion prevention layer on a surface of the first metal layer opposite to the core resin layer. [9]

[0032] The method for manufacturing a coreless substrate according to [8], further comprising, after the diffusion prevention layer forming step, a plating resist forming step of forming a plating resist on a surface of the diffusion prevention layer opposite to the first metal layer.

[10]

[0034] The method for manufacturing a coreless substrate according to [9], further comprising, after forming the plating resist, a protective plating layer forming step of forming a protective plating layer in a region of the diffusion prevention layer opposite to the first metal layer where the plating resist is not provided.

[11]

[0036] The method for manufacturing a coreless substrate according to [8], wherein before the diffusion prevention layer forming step, a plating resist forming step of forming a plating resist on a surface of the first metal layer opposite to the core resin layer is included.

[0037] The diffusion prevention layer is formed in a region of the surface of the first metal layer on the opposite side to the core resin layer where the plating resist is not formed.

[12]

[0039] The method for manufacturing a coreless substrate according to

[11] , further comprising, after the diffusion prevention layer forming step, a protective plating layer forming step of forming a protective plating layer on a side of the diffusion prevention layer opposite to the first metal layer.

[13]

[0041] The method for manufacturing a coreless substrate according to [8], wherein the diffusion prevention layer includes at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium.

[14]

[0043] The method for manufacturing a coreless substrate according to [8], wherein a thickness of the first metal layer from an end surface on the diffusion prevention layer side to the peeling unit is 6 μm or more.

[0044] Effects of the Invention

[0045] According to the present invention, a first metal layer having a stripping unit is provided on at least one side of the core resin layer, and a diffusion-preventing layer is provided on the surface of the first metal layer opposite to the core resin layer. Therefore, after the core resin layer is separated and removed in the stripping unit, when the remaining first metal layer is removed by etching, the diffusion-preventing layer can be used as an etching stopper. Therefore, the remaining first metal layer can be easily removed. In addition, since the constituent elements of the first metal layer and the protective plating layer formed thereon can be suppressed from mutually diffusing, a good protective plating layer can be formed.

[0046] Furthermore, by making the thickness of the first metal layer from the end surface on the diffusion prevention layer side to the peeling unit 6 μm or more, after forming the wiring board on the first metal layer, the wiring board can be reinforced to suppress damage when the core resin layer is separated and removed in the peeling unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a figure which shows the structure of the laminated body which concerns on 1st Embodiment of this invention.

[0048] Figure 2 Yes means Figure 1 A diagram showing the steps of a method for producing a laminated body.

[0049] Figure 3 It means using Figure 1 FIG. 1 is a diagram showing steps of a first method for manufacturing a wiring substrate with a support and a coreless substrate of a laminate.

[0050] Figure 4 Yes means Figure 3 Diagram of subsequent processes.

[0051] Figure 5 Yes means Figure 4 Diagram of subsequent processes.

[0052] Figure 6 It means using Figure 1 FIG. 2 is a diagram showing the steps of a second method for manufacturing a wiring substrate with a support and a coreless substrate of a laminate.

[0053] Figure 7 Yes means Figure 6 Diagram of subsequent processes.

[0054] Figure 8 Yes means Figure 7 Diagram of subsequent processes.

[0055] Fig. 9 It means using Figure 1 FIG. 2 is a diagram showing the steps of a third method for manufacturing a wiring substrate with a support and a coreless substrate of a laminate.

[0056] Fig.10 Yes means Fig. 9 Diagram of subsequent processes.

[0057] Fig.11 It is a figure which shows the structure of the laminated body which concerns on the modification of this invention.

[0058] Fig.12 Yes means Fig.11 A diagram showing the steps of a method for producing a laminate. DETAILED DESCRIPTION

[0059] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described in detail, but the present invention is not limited thereto and various modifications can be made without departing from the gist of the present invention.

[0060] [First embodiment]

[0061] Figure 1The structure of the laminate 10 according to the first embodiment of the present invention is shown. The laminate 10 comprises: a core resin layer 11, a first metal layer 12 provided on at least one side of the core resin layer 11 and having a peeling unit, a diffusion prevention layer 13 provided on the surface of the first metal layer 12 opposite to the core resin layer 11, and a plating resistance layer 14 provided on the surface of the diffusion prevention layer 13 opposite to the first metal layer 12. Furthermore, a protective plating layer 15 may be provided in a region of the diffusion prevention layer 13 opposite to the first metal layer 12 where the plating resistance layer 14 is not provided. The laminate 10 may be used, for example, in the manufacture of a wiring substrate 20 with a support (for example, see Figure 3 , 4 ) and the coreless substrate 30 (see, for example Figure 5 ) is used when

[0062] The wiring substrate with support 20 comprises: a support 10A having a first metal layer 12 provided on at least one side of a core resin layer 11, and a wiring substrate 20A provided on the first metal layer 12 (see, for example, Figure 3 , 4 ). The wiring substrate 20 with a support is also called, for example, a printed wiring board with a support or a packaged substrate with a support. As a wiring substrate 20A, it has a printed wiring board or a packaged substrate for mounting semiconductor elements. The printed wiring board or the packaged substrate for mounting semiconductor elements constitutes an electronic component mounting substrate by mounting electronic components such as semiconductor elements. The wiring substrate 20A is not limited to mounting semiconductor elements, and for example, it can also mount surface-mounted electronic components such as LED (Light Emitting Diode) elements, capacitors, resistors, coils, etc. The coreless substrate 30 is obtained by separating the support 10A from the wiring substrate 20 with a support (for example, refer to Figure 5 ).

[0063] <Configuration of Laminated Body>

[0064] (Core resin layer)

[0065] The core resin layer 11 is used to increase the rigidity of the wiring substrate 20A, suppress warping, and improve operability in the manufacturing process of the wiring substrate 20A or the mounting process of the semiconductor element. Figure 1The illustrated case is that the first metal layer 12 is disposed on one side of the core resin layer 11, but the first metal layer 12 may also be disposed on both sides of the core resin layer 11. The core resin layer 11 is not particularly limited, and may be, for example, composed of a prepreg, an insulating film material, etc., in which an insulating resin material (insulating material) such as a thermosetting resin is impregnated in a substrate such as glass cloth. The thickness of the core resin layer 11 is appropriately set as desired, and therefore is not particularly limited, and is, for example, preferably greater than 1 μm. This is because when the thickness of the core resin layer 11 is less than 1 μm, the wiring substrate 20A may sometimes be poorly formed.

[0066] "Prepreg" is formed by impregnating or coating an insulating material such as a resin composition on a substrate. The substrate is not particularly limited, and a known substrate can be used appropriately. Examples of materials constituting the substrate include inorganic fibers such as E glass, D glass, S glass, or Q glass; organic fibers such as polyimide, polyester, or tetrafluoroethylene; and mixtures thereof. The substrate is not particularly limited, and a substrate with a shape such as a woven fabric, a non-woven fabric, a roving, a chopped strand mat, a surface mat, etc. can be used appropriately. The material and shape of the substrate are selected according to the purpose and performance of the target molded product, and a single material or two or more materials and shapes can be used as needed.

[0067] As long as the thickness of the core resin layer 11 is within the above range, the thickness of the substrate is not particularly limited. In addition, as the substrate, a substrate surface-treated with a silane coupling agent or the like, or a substrate mechanically subjected to a fiber-opening treatment can be used, and these substrates are suitable from the aspects of heat resistance, moisture resistance, and processability.

[0068] As insulating material, it is not particularly limited, and known resin combination used as insulating material of printed wiring board or semiconductor element mounting package substrate can be appropriately selected. As resin combination, thermosetting resin with good heat resistance and chemical resistance can be used as matrix. As thermosetting resin, it is not particularly limited, for example, polyimide resin, phenolic resin, epoxy resin, cyanate resin, maleimide resin, modified polyphenylene ether, bismaleimide triazine resin, isocyanate resin, benzocyclobutene resin and vinyl resin can be cited. These thermosetting resins can be used alone or in combination.

[0069] As polyimide resin, it is not particularly limited, and commercially available products can be appropriately selected for use. For example, solvent-soluble polyimide resins and block copolymer polyimide resins synthesized by the manufacturing method described in Japanese Patent Publication No. 2005-15629 can be used. As block copolymer polyimide resins, for example, block copolymer polyimide resins described in International Publication No. WO2010-073952 can be cited. Specifically, block copolymer polyimide resins are not particularly limited as long as they are copolymer polyimide resins with structures A and B alternately repeated, and the structure A is bonded to the end of the imide oligomer containing the first structural unit, and the structure B is bonded to the end of the imide oligomer containing the second structural unit, and the imide oligomer containing the first structural unit is bonded to the end of the imide oligomer containing the second structural unit. It should be noted that the second structural unit is different from the first structural unit. These block copolymer polyimide resins can be synthesized by reacting tetracarboxylic dianhydride with diamine in a polar solvent to prepare an imide oligomer, and then further adding tetracarboxylic dianhydride and other diamines or adding other tetracarboxylic dianhydrides and diamines to carry out imidization stepwise polymerization. These polyimide resins can be used alone or in combination of two or more.

[0070] The phenolic resin is not particularly limited, and any commonly known compound or resin may be used as long as it is a compound or resin having one or more (preferably 2 to 12, more preferably 2 to 6, further preferably 2 to 4, further preferably 2 or 3, further preferably 2) phenolic hydroxyl groups in one molecule. For example, bisphenol A type phenolic resin, bisphenol E type phenolic resin, bisphenol F type phenolic resin, bisphenol S type phenolic resin, phenol novolac resin, bisphenol A novolac type phenolic resin, glycidyl ester type phenolic resin, aralkyl novolac type phenolic resin, biphenyl aralkyl type phenolic resin, cresol novolac type phenolic resin, multifunctional phenolic resin, naphthol resin, naphthol novolac resin, multifunctional naphthol resin, anthracene type phenolic resin, naphthalene skeleton modified novolac type phenolic resin, phenol aralkyl type phenolic resin, naphthol aralkyl type phenolic resin, dicyclopentadiene type phenolic resin, biphenyl type phenolic resin, alicyclic phenolic resin, polyol type phenolic resin, phosphorus-containing phenolic resin and hydroxyl-containing silicone resin can be cited. These phenolic resins can be used alone or in combination of two or more.

[0071] Among thermosetting resins, epoxy resins have excellent heat resistance, chemical resistance and electrical properties, and are relatively cheap, so they can be used as insulating materials. As epoxy resins, there are no particular restrictions as long as they are compounds or resins having one or more (preferably 2 to 12, more preferably 2 to 6, further preferably 2 to 4, further preferably 2 or 3, further preferably 2) epoxy groups in one molecule, for example, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, alicyclic epoxy resins, aliphatic chain epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A novolac type epoxy resins, diglycidyl ethers of biphenols, diglycidyl ethers of naphthalene diols, diglycidyl ethers of phenols, diglycidyl ethers of alcohols, and their alkyl substituents, halides, and hydrides. These epoxy resins can be used alone or in combination of two or more. In addition, the curing agent used together with the epoxy resin can be used without limitation as long as it is a curing agent that cures the epoxy resin, and examples thereof include polyfunctional phenols, polyfunctional alcohols, amines, imidazole compounds, acid anhydrides, organic phosphorus compounds, and halides thereof. These epoxy resin curing agents can be used alone or in combination of two or more.

[0072] Cyanate resin is a resin that generates a cured product with triazine ring as a repeating unit by heating, and the cured product has excellent dielectric properties. Therefore, it is particularly suitable for situations where high-frequency characteristics are required. As a cyanate resin, there is no particular limitation as long as it is a compound or resin having an aromatic part substituted with one or more (preferably 2 to 12, more preferably 2 to 6, further preferably 2 to 4, further preferably 2 or 3, further preferably 2) cyanate groups (cyanate groups) in the molecule. For example, 2,2-bis(4-cyanatophenyl)propane, bis(4-cyanatophenyl)ethane, 2,2-bis(3,5-dimethyl-4-cyanatophenyl)methane, 2,2-(4-cyanatophenyl)-1,1,3,3,3-hexafluoropropane, α,α'-bis(4-cyanatophenyl)-m-diisopropylbenzene, phenol novolac, and cyanate esters of alkylphenol novolac can be cited. Among them, due to the particularly good balance of dielectric properties and curability of the cured product of 2,2-bis(4-cyanophenyl)propane, the cost is also low, so it is preferred. These cyanate resins such as cyanate compounds can be used alone or in combination with two or more. In addition, the cyanate compound can be partially oligomerized into trimers and pentamers in advance.

[0073] Furthermore, a curing catalyst and a curing accelerator may be used in combination with the cyanate resin. As the curing catalyst, metals such as manganese, iron, cobalt, nickel, copper, zinc, etc. may be used, and specifically, organic metal salts such as 2-ethylhexanoate and octanoate, and organic metal complexes such as acetylacetone complex may be cited. The curing catalyst may be used alone or in combination of two or more.

[0074] In addition, phenols are preferably used as curing accelerators, and monofunctional phenols such as nonylphenol and p-cumylphenol, bifunctional phenols such as bisphenol A, bisphenol F, and bisphenol S, or polyfunctional phenols such as phenol novolac and cresol novolac can be used. One type of curing accelerator can be used alone, or two or more types can be mixed and used.

[0075] As the maleimide resin, any commonly known compound or resin may be used as long as it is a compound or resin having one or more (preferably 2 to 12, more preferably 2 to 6, further preferably 2 to 4, further preferably 2 or 3, further preferably 2) maleimide groups in one molecule. Examples thereof include 4,4-diphenylmethane bismaleimide, phenylmethane maleimide, m-phenylene bismaleimide, 2,2-bis(4-(4-maleimidephenoxy)-phenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 4,4-diphenylether bismaleimide, 4,4-diphenylsulfone bismaleimide, 1,3-bis(3-maleimide phenoxy)benzene, 1,3-bis(4-maleimide phenoxy)benzene, polyphenylmethane maleimide, novolac maleimide, biphenyl aralkyl maleimide, and prepolymers of these maleimide compounds, or prepolymers of maleimide compounds and amine compounds, but not particularly limited. These maleimide resins may be used alone or in combination of two or more.

[0076] Modified polyphenylene ether is useful from the viewpoint of being able to improve the dielectric properties of the cured product. As modified polyphenylene ether, for example, poly(2,6-dimethyl-1,4-phenylene) ether, alloy polymer of poly(2,6-dimethyl-1,4-phenylene) ether and polystyrene, alloy polymer of poly(2,6-dimethyl-1,4-phenylene) ether and styrene-butadiene copolymer, alloy polymer of poly(2,6-dimethyl-1,4-phenylene) ether and styrene-maleic anhydride copolymer, alloy polymer of poly(3,6-dimethyl-1,4-phenylene) ether and polyamide, alloy polymer of poly(2,6-dimethyl-1,4-phenylene) ether and styrene-butadiene-acrylonitrile copolymer, oligophenylene ether, etc. can be cited. In order to impart reactivity and polymerizability to polyphenylene ether, functional groups such as amine, epoxy, carboxyl, styryl, etc. may be introduced at the polymer chain end or at the polymer chain side chain.

[0077] The isocyanate resin is not particularly limited, and for example, there are isocyanate resins obtained by dehydrohalogenation reaction of phenols and halogenated cyanogens. As isocyanate resins, for example, 4,4'-diphenylmethane diisocyanate MDI, polymethylene polyphenyl polyisocyanate, toluene diisocyanate, and hexamethylene diisocyanate can be cited. These isocyanate resins can be used alone or in combination of two or more.

[0078] The benzocyclobutene resin is not particularly limited as long as it is a resin containing a cyclobutene skeleton, and for example, divinylsiloxane-bisbenzocyclobutene (manufactured by The Dow Chemical Company) can be used. These benzocyclobutene resins may be used alone or in combination of two or more.

[0079] The vinyl resin is not particularly limited as long as it is a polymer or copolymer of a vinyl monomer. The vinyl monomer is not particularly limited, and examples thereof include (meth)acrylate derivatives, vinyl ester derivatives, maleic acid diester derivatives, (meth)acrylamide derivatives, styrene derivatives, vinyl ether derivatives, vinyl ketone derivatives, olefin derivatives, maleimide derivatives, and (meth)acrylonitrile. One of these vinyl resins may be used alone, or two or more of them may be used in combination.

[0080] For the resin composition used as an insulating material, from the aspects of dielectric properties, impact resistance and film processability, thermoplastic resins can also be blended. Thermoplastic resins are not particularly limited, for example, fluororesins, polycarbonates, polyetherimides, polyetheretherketones, polyacrylates, polyamides, polyamideimides, polybutadiene, etc. can be cited. Thermoplastic resins can be used alone in one kind, or two or more kinds can be mixed. In addition, fluororesins are not particularly limited, for example, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride and polyvinyl fluoride can be cited. These fluororesins can be used alone in one kind, or two or more kinds can be mixed.

[0081] Among thermoplastic resins, polyamide-imide resins are useful from the viewpoint of excellent moisture resistance and good adhesiveness to metals. The raw materials of polyamide-imide resins are not particularly limited. As acidic components, trimellitic anhydride and trimellitic anhydride monochloride can be cited, and as amine components, metaphenylenediamine, paraphenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, bis[4-(aminophenoxy)phenyl]sulfone, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, etc. can be cited. In order to improve drying properties, polyamide-imide resins can be siloxane-modified, and in this case, siloxane diamine can be used as an amino component. From the aspect of film processability, it is preferred to use a polyamide-imide resin having a molecular weight of 50,000 or more.

[0082] The resin composition used as an insulating material can be mixed with a filling material. As a filling material, there is no particular limitation, for example, metal oxides (including hydrates) such as aluminum oxide, white carbon, titanium dioxide, titanium oxide, zinc oxide, magnesium oxide, zirconium oxide, aluminum hydroxide, boehmite, magnesium hydroxide, natural silica, fused silica, synthetic silica, amorphous silica, AEROSIL, hollow silica and other silicas, inorganic filling materials (inorganic filling materials) such as clay, kaolin, talc, mica, glass powder, quartz powder, volcanic ash balls, and organic filling materials (organic filling materials) such as rubber powders of styrene type, butadiene type, acrylic acid type, core-shell rubber powder, silicone resin powder, silicone rubber powder, silicone composite powder, etc. can be cited. These filling materials can be used alone or in combination.

[0083] The resin composition used as an insulating material may contain an organic solvent. There is no particular limitation on the organic solvent, and aromatic hydrocarbon solvents such as benzene, toluene, xylene, and trimethylbenzene can be used in combination as needed; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ether solvents such as tetrahydrofuran; alcohol solvents such as isopropanol and butanol; ether alcohol solvents such as 2-methoxyethanol and 2-butoxyethanol; amide solvents such as N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. It should be noted that the amount of solvent in the varnish when making the prepreg is preferably in the range of 40% to 80% by mass relative to the entire resin composition. In addition, the viscosity of the varnish is ideally in the range of 20cP to 100cP (20mPa·s to 100mPa·s).

[0084] The resin composition used as an insulating material may contain a flame retardant. The flame retardant is not particularly limited, and for example, bromine compounds such as decabromodiphenyl ether, tetrabromobisphenol A, tetrabromophthalic anhydride, tribromophenol, phosphorus compounds such as triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, red phosphorus and its modified products, antimony compounds such as antimony trioxide and antimony pentoxide, triazine compounds such as melamine, cyanuric acid, and melamine cyanurate can be used.

[0085] The resin composition used as an insulating material may further contain the above-mentioned curing agent, curing accelerator, thermoplastic particles, coloring agent, ultraviolet light-blocking agent, antioxidant, reducing agent and other various additives and fillers as needed.

[0086] The prepreg in this embodiment can be obtained by, for example, impregnating or coating the substrate with the resin composition (including varnish) in such a manner that the amount of the resin composition attached to the substrate is 20% by mass or more and 90% by mass or less in terms of the resin content in the dried prepreg, and then heating and drying at a temperature of 100° C. to 200° C. for 1 minute to 30 minutes. As such a prepreg, for example, GHPL-830NS (product name) and GHPL-830NSF (product name) manufactured by Mitsubishi Gas Chemical Co., Ltd. can be used.

[0087] The insulating film material can be composed of, for example, the resin composition of the insulating material described in the prepreg, and can be obtained by processing the resin composition into a film shape.

[0088] (1st metal layer)

[0089] The first metal layer 12 and the core resin layer 11 together constitute the support body 10A. The first metal layer 12 can be composed of, for example, a metal foil with a carrier. The metal foil with a carrier is, for example, formed by laminating a metal foil 12B on a carrier 12A with a peeling layer (not shown) as a peeling unit. The metal foil with a carrier can use a commercially available product, for example, MT18SD-H-T5 (product name) manufactured by Mitsui Mining and Smelting Co., Ltd. can be used. The thickness of the first metal layer 12 is appropriately set according to the desired thickness, and therefore is not particularly limited, and can be, for example, not less than 0.5 μm and not more than 100 μm.

[0090] The carrier 12A may be made of, for example, various metal foils, and is preferably made of copper foil in view of thickness uniformity and corrosion resistance of the foil. The thickness of the carrier 12A is thicker than that of the metal foil 12B, and may be, for example, 3 μm or more and 100 μm or less, preferably 5 μm or more and 50 μm or less, and more preferably 6 μm or more and 30 μm or less.

[0091] The peeling layer is a substance used to make the carrier 12A and the metal foil 12B easily peelable. The material of the peeling layer is not particularly limited, and various known materials can be used appropriately. For example, if it is an organic material, nitrogen-containing organic compounds, sulfur-containing organic compounds, carboxylic acids, etc. can be cited. As examples of nitrogen-containing organic compounds, triazole compounds, imidazole compounds, etc. can be cited, among which triazole compounds are preferred in terms of easy and stable peelability. As examples of triazole compounds, 1,2,3-benzotriazole, carboxybenzotriazole, N',N'-bis(benzotriazolylmethyl)urea, 1H-1,2,4-triazole and 3-amino-1H-1,2,4-triazole can be cited. As examples of sulfur-containing organic compounds, mercaptobenzothiazole, trithiocyanate, 2-benzimidazolethiol, etc. can be cited. As examples of carboxylic acids, monocarboxylic acids, dicarboxylic acids, etc. can be cited. Inorganic materials include metals or alloys formed from at least one of Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, etc., or oxides thereof. The thickness of the peeling layer may be, for example, 1 nm to 1 μm, preferably 5 nm to 500 nm.

[0092] The metal foil 12B can be made of various metal foils, and is preferably made of copper foil in view of the uniformity of thickness and the corrosion resistance of the foil. The thickness of the metal foil 12B is appropriately set according to the desired thickness, and is therefore not particularly limited. For example, it can be 0.5 μm or more and 70 μm or less, preferably 1 μm or more and 50 μm or less, and more preferably 6 μm or more and 30 μm or less.

[0093] In the first metal layer 12, the carrier 12A may be provided on the core resin layer 11 side and the metal foil 12B may be provided on the diffusion prevention layer 13 side, or the metal foil 12B may be provided on the core resin layer 11 side and the carrier 12A may be provided on the diffusion prevention layer 13 side. Figure 1 The case shown is where the carrier 12A is provided on the core resin layer 11 side and the metal foil 12B is provided on the diffusion prevention layer 13 side. The thickness of the first metal layer 12 from the end surface on the diffusion prevention layer 13 side to the peeling unit ( Figure 1 In the example of , the thickness of the metal foil 12B is preferably 6 μm or more, more preferably 10 μm or more, and further preferably 15 μm or more. This is because after the wiring substrate 20A is formed on the first metal layer 12, when the core resin layer 11 is separated in the stripping unit, the wiring substrate 20A can be reinforced to suppress damage. In addition, the thickness of the first metal layer 12 from the end face on the diffusion prevention layer 13 side to the stripping unit is preferably 70 μm or less, more preferably 50 μm or less, and further preferably 30 μm or less. This is because if the thickness of the first metal layer 12 remaining on the diffusion prevention layer 13 side is too thick, it will take time to remove it by etching.

[0094] In addition, although not shown, the first metal layer 12 may also be composed of a metal foil having a release layer as a stripping unit. In this case, the release layer is laminated on one side of the core resin layer 11. As a release layer, for example, a layer containing at least a silicon compound can be cited, for example, it can be formed by imparting a silicon compound formed by a single or combined plurality of silane compounds on a metal foil. It should be noted that the means for imparting the silicon compound is not particularly limited, for example, known means such as coating can be used. The bonding surface of the metal foil with the release layer can be subjected to rust prevention treatment (forming a rust prevention treatment layer). The rust prevention treatment can be carried out using any one of nickel, tin, zinc, chromium, molybdenum, cobalt or their alloys. The thickness of the release layer is not particularly limited, and is preferably 5 nm or more and 100 nm or less from the viewpoint of removability and stripping properties, more preferably 10 nm or more and 80 nm or less, and particularly preferably 20 nm or more and 60 nm or less. In addition, as a metal foil, copper foil is preferred from the perspectives of thickness uniformity and corrosion resistance of the foil. In this case, the thickness of the first metal layer 12 from the end surface on the diffusion prevention layer 13 side to the peeling unit is also preferably the above-mentioned thickness.

[0095] (Anti-diffusion layer)

[0096] The diffusion prevention layer 13 is a layer that functions as an etching stopper when the remaining first metal layer 12 is removed by etching after the core resin layer 11 is separated and removed in the stripping unit, and is used to suppress the mutual diffusion of the constituent elements of the first metal layer 12 and the protective plating layer 15 and the corrosion of the protective plating layer 15 when the protective plating layer 15 is provided on the first metal layer 12. The diffusion prevention layer 13 preferably contains at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver and palladium. This is because the above-mentioned functions can be obtained. The diffusion prevention layer 13 can be, for example, provided to be in contact with the first metal layer 12. The thickness of the diffusion prevention layer 13 can be, for example, not less than 0.5 μm and not more than 10 μm.

[0097] (Anti-plating)

[0098] The anti-plating layer 14 is, for example, disposed in contact with the diffusion prevention layer 13, and is provided with an opening corresponding to the terminal position of the wiring substrate 20A formed on the first metal layer 12. It should be noted that the terminal position of the wiring substrate 20A refers to the position of the external connection terminal when the wiring substrate 20A is mounted on an electronic device, for example, by welding. The anti-plating layer 14, for example, contains an insulating resin material, and can be composed of a dry film protective agent, an insulating film material or prepreg described in the core resin layer 11. The anti-plating layer 14 can be removed after the diffusion prevention layer 13 and the protective plating layer 15 are formed, or the wiring substrate 20A can be formed thereon without being removed. This is because after the support 10A is separated and removed from the wiring substrate 20 with the support in the stripping unit, it can function as a solder resist.

[0099] When the plating resist 14 is used as a solder resist, the insulating resin material preferably has a glass transition temperature of 150°C or more. This is because if the glass transition temperature is lower than 150°C, expansion may occur during the processing step, and the wiring substrate 20A may be damaged. As the insulating resin material of the plating resist 14, it is preferred to include a material with excellent heat resistance, such as at least one selected from polyimide resin, epoxy resin, cyanate resin, maleimide resin, bismaleimide triazine resin, polyamide-imide resin, nylon resin as a polyamide resin, and fluororesin. Among them, it is preferred to include at least one selected from polyimide resin, bismaleimide triazine resin, and fluororesin.

[0100] The thickness of the plating resist 14 is appropriately set as desired, for example, 1 μm to 100 μm, preferably 1 μm to 30 μm, and more preferably 1 μm to 9 μm. This is to reduce the total thickness of the wiring board 20A.

[0101] (Protective coating)

[0102] The protective plating layer 15 protects the surface of the external connection terminal of the wiring substrate 20A. The protective plating layer 15 preferably includes, for example, a gold plating layer 15A containing gold and a nickel plating layer 15B containing nickel from the side of the diffusion prevention layer 13. The thickness of the gold plating layer 15A can be set to, for example, 0.05 μm or more and 0.1 μm or less, and the thickness of the nickel plating layer 15B can be set to, for example, 0.5 μm or more and 10 μm or less.

[0103] <Method for producing laminate>

[0104] Figure 2 A method for manufacturing the laminate 10 is shown. First, for example, Figure 2 As shown in (A), a support 10A having a core resin layer 11 and a first metal layer 12 provided on at least one side of the core resin layer and having a peeling unit is prepared (support preparation step). Specifically, for example, a metal foil with a carrier or a metal foil having a release layer is provided on at least one side of the core resin layer 11, and the support 10A is formed by heating and pressurizing. Next, for example, Figure 2 As shown in (B), the diffusion prevention layer 13 is formed on the surface of the first metal layer 12 on the opposite side to the core resin layer 11 by electrolytic plating (diffusion prevention layer forming step).

[0105] Then, for example Figure 2 As shown in (C), a plating resist 14 is formed on the surface of the diffusion prevention layer 13 on the opposite side to the first metal layer 12 (plating resist forming step). Specifically, for example, after a dry film protective agent is laminated on the diffusion prevention layer 13, the circuit pattern on the dry film protective agent is baked and developed, thereby forming the plating resist 14. In addition, for example, a metal foil with a carrier having a resin layer is provided on the diffusion prevention layer 13 in such a manner that the resin layer is on the diffusion prevention layer 13 side, and after heating and pressing, the carrier is peeled off, a dry film protective agent is laminated on the metal foil, and baked and developed to form a protective pattern, then the metal foil is etched to form a mask, and the protective pattern is removed, and then the portion of the resin layer not covered by the mask is removed by laser processing or the like, and the mask is removed, thereby forming the plating resist 14.

[0106] Then, for example Figure 2 As shown in (D), the protective plating layer 15 is formed by electrolytic plating in the area of ​​the diffusion prevention layer 13 opposite to the first metal layer 12 where the plating resist 14 is not provided (protective plating layer forming step). Specifically, for example, the gold plating layer 15A and the nickel plating layer 15B are sequentially stacked by electrolytic plating.

[0107] <First Manufacturing Method of Wiring Substrate with Support and Coreless Substrate>

[0108] The laminated body 10 can be used when manufacturing the wiring substrate with support 20 and the coreless substrate 30 . Figures 3 to 5The steps of the first method for manufacturing the wiring substrate with support 20 and the coreless substrate 30 are shown. First, for example, the laminate 10 is formed in the above-mentioned manner (support preparation step, diffusion prevention layer formation step, plating resistance layer formation step, and protective plating layer formation step). Then, for example, Figure 3 As shown in (A), the first wiring conductor 21 is formed by electrolytic plating, for example, electrolytic copper plating, in a region of the protective plating layer 15 on the opposite side from the diffusion prevention layer 13 where the plating resist 14 is not provided (first wiring conductor forming step).

[0109] Then, for example Figure 3 As shown in (B), a first insulating layer 22 is formed on the first wiring conductor 21 and the anti-plating layer 14, and a second wiring conductor 23 is formed thereon, thereby forming a wiring substrate 20 with a support having two layers of wiring conductors (first insulating layer forming step, second wiring conductor forming step). Specifically, first, for example, in order to improve the adhesion with the first insulating layer 22, the surface of the first wiring conductor 21 is subjected to a roughening treatment. The roughening treatment is not particularly limited, and known means can be used appropriately, for example, means using a copper surface roughening liquid can be cited. Next, for example, a metal foil with a resin layer is arranged on the first wiring conductor 21 and the anti-plating layer 14 in such a manner that the resin layer is in contact with the first wiring conductor 21, and the first insulating layer 22 and the second metal layer are stacked in sequence. The metal foil with a resin layer is, for example, formed by stacking a resin layer on the metal foil side of the metal foil with a carrier, and the resin layer becomes the first insulating layer 22, and the metal foil becomes the second metal layer.

[0110] Next, for example, by laser processing using a carbon dioxide laser or the like, a hole is formed on the second metal layer and the first insulating layer 22 to form a first non-through hole 22A reaching the first wiring conductor 21, and a desmear treatment is performed. Next, for example, the second wiring conductor 23 is formed by a known method such as a subtractive method or a semi-additive method. In the case of the subtractive method, for example, at least one of chemical plating and electrolytic plating is firstly performed on the surface formed with the first non-through hole 22A, and a first connecting through hole 22B for connecting the first wiring conductor 21 and the second metal layer is formed on the inner wall of the first non-through hole 22A, and the thickness of the second metal layer is increased, and the surface is adjusted as needed. Next, for example, a dry film protective agent is laminated, a negative mask is attached, and the circuit pattern is baked, and a development is performed to form an anti-etching layer. Next, for example, the second metal layer with an increased thickness is etched using the anti-etching layer as a mask to form the second wiring conductor 23, and the anti-etching layer is removed.

[0111] In the case of the semi-additive method, for example, after first forming the first non-through hole 22A, the second metal layer is completely removed by etching or the like to expose the first insulating layer 22. Next, for example, chemical plating is performed to form the first connecting through hole 22B on the inner wall of the first non-through hole 22A, and a chemical plating layer is formed on the first insulating layer 22. Next, for example, a dry film is thermally pressed on the chemical plating layer to provide a protective layer, and exposure and development are performed to form a protective pattern and remove scum (protective agent residue). Next, for example, the protective pattern is used as a plating resist, and an electrolytic plating layer is formed on the surface of the chemical copper plating layer by electrolytic plating. After removing the protective pattern, the exposed chemical plating layer is etched to form the second wiring conductor 23 including the chemical plating layer and the electrolytic plating layer.

[0112] After the second wiring conductor 23 is formed, for example, Figure 3 As shown in (C), the same steps as the first insulating layer forming step and the second wiring conductor forming step can be repeated n times to form a layered structure (layered step) having (n+2) layers of wiring conductors. Figure 3 (C) shows a case where the same steps as the first insulating layer forming step and the second wiring conductor forming step are repeated four times to form a laminated structure of a wiring substrate with a support body 20 having six layers of wiring conductors. Specifically, for example, the "(m+1)th insulating layer forming step of forming the (m+1)th insulating layer 24 on the (m)th insulating layer 22, 24 and the (m+1)th wiring conductor 23, 25, and the (m+1)th non-through hole 24A reaching the (m+1)th wiring conductor 23, 25 on the (m+1)th insulating layer 24, and the (m+2)th wiring conductor forming step of forming the (m+2)th wiring conductor 25" can be performed n times in sequence to form a laminated structure (laminate step). m and n are integers greater than 1, where m≤n.

[0113] After forming the first insulating layer 22 and the second wiring conductor 23 or after forming the (n+1)th insulating layer 24 and the (n+2)th wiring conductor 25, for example, Figure 4 As shown in (D), a solder resist layer 26 is formed on these so that the second wiring conductor 23 or the (n+2)th wiring conductor 25 is partially exposed (solder resist layer forming step). The method for forming the solder resist layer 26 is not particularly limited, and a known method can be appropriately adopted.

[0114] After forming the solder resist layer 26, for example Figure 4As shown in (E), a protective plating layer 27 is formed by electrolytic plating on the second wiring conductor 23 or the (n+2)th wiring conductor 25 exposed from the solder resist layer 26 (plating finishing process). Specifically, for example, a nickel-plated layer 27A containing nickel and a gold-plated layer 27B containing gold are stacked in order from the second wiring conductor 23 or the (n+2)th wiring conductor 25 side.

[0115] After forming the protective plating layer 27, for example Figure 5 As shown in (F), the core resin layer 11 is separated and removed from the wiring substrate 20 with a support body (core resin layer separation and removal process). The separation and removal of the core resin layer 11 is performed, for example, by peeling in a peeling unit (such as a peeling layer or a demolding layer) of the first metal layer 12. The peeling can be performed by any of physical means or chemical means. For example, it is preferred to apply a physical force to the peeling unit and perform the peeling by physical means. By this peeling, the core resin layer 11 and, depending on the circumstances, a portion of the first metal layer 12 are peeled off. At least a portion of the peeling unit of the first metal layer 12 may be peeled off at least together with the core resin layer 11, or may remain without being peeled off.

[0116] After the core resin layer 11 is separated and removed, for example Figure 5 As shown in (G), the remaining first metal layer 12 and the diffusion prevention layer 13 are removed (first metal layer / diffusion prevention layer removal process). The means for removing the first metal layer 12 and the diffusion prevention layer 13 are not particularly limited, for example, they can be removed using a sulfuric acid-based or hydrogen peroxide-based etching solution. The sulfuric acid-based or hydrogen peroxide-based etching solution is not particularly limited, and the etching solution used in the art can be used. At this time, since the diffusion prevention layer 13 is provided between the first metal layer 12 and the protective plating layer 15, the diffusion prevention layer 13 is used as an etching barrier layer, and the remaining first metal layer 12 can be easily removed. In addition, the mutual diffusion of the constituent elements of the first metal layer 12 and the protective plating layer 15 can be suppressed, and a good protective plating layer can be formed. Thus, a coreless substrate 30 is obtained. It should be noted that in the coreless substrate 30, the anti-plating layer 14 is used as a solder resist.

[0117] <Second Manufacturing Method of Wiring Substrate with Support and Coreless Substrate>

[0118] Figures 6 to 8 The second manufacturing method of the support-attached wiring substrate 20 and the coreless substrate 30 is shown. The second manufacturing method is the same as the first manufacturing method except that a resist removal step of removing the resist 14 using a protective agent stripping liquid is included after the first wiring conductor forming step and before the first insulating layer forming step / the second wiring conductor forming step. That is, the second manufacturing method includes, for example, a support preparation step (see Figure 2 (A)), diffusion prevention layer forming step (refer to Figure 2(B)), resist forming step (refer to Figure 2 (C)), protective plating layer forming step (refer to Figure 2 (D)), first wiring conductor forming step (refer to Figure 3 (A)), resist removal process (refer to Figure 6 (A)), first insulating layer forming step / second wiring conductor forming step (refer to Figure 6 (B)), lamination process (refer to Figure 6 (C)), solder mask forming process (refer to Figure 7 (D)), plating finishing process (refer to Figure 7 (E)), core resin layer separation and removal process (refer to Figure 8 (F)), first metal layer / diffusion prevention layer removal step (refer to Figure 8 (G)). Therefore, detailed description of the same process will be omitted with reference to the drawings. It should be noted that in the coreless substrate 30 obtained by the second manufacturing method, the first insulating layer 22 is used as a solder resist layer.

[0119] <Third Manufacturing Method of Wiring Substrate with Support and Coreless Substrate>

[0120] Fig. 9 and Fig.10 The third manufacturing method of the wiring substrate 20 with a support and the coreless substrate 30 is shown. The third manufacturing method is the same as the first manufacturing method or the second manufacturing method except that it includes a support substrate stacking step of stacking the support substrate 28 after the plating finishing step, and a support substrate removal step of removing the support substrate 28 after the first metal layer / diffusion prevention layer removal step. Since the support preparation step to the plating finishing step are the same as the first manufacturing method or the second manufacturing method, the detailed description is omitted. It should be noted that Fig. 9 and Fig.10 This shows a case where the plating resist 14 is used without being removed, similarly to the first manufacturing method.

[0121] In the third manufacturing method, after the plating finishing step, for example, Fig. 9 As shown in (A), a support substrate 28 having a thermoplastic resin layer is stacked on the solder resist layer 26 and the protective plating layer 27 (support substrate stacking step). The support substrate 28 is used to reinforce the wiring substrate 20A to prevent damage in the subsequent core resin layer separation and removal step, at least when the core resin layer is separated and removed.

[0122] The support substrate 28 may have a thermosetting resin layer in addition to a thermoplastic resin layer, or may be composed only of a thermoplastic resin layer. This is because thermoplastic resins have higher toughness than thermosetting resins and can obtain high strength. The material of the thermoplastic resin layer is not particularly limited, and for example, a dry film protective agent can be cited. Among them, it is preferably composed of a photosensitive resin layer containing a photosensitive thermoplastic resin. This is because the wiring conductor formation process can be used. As a photosensitive thermoplastic resin, for example, a dry film protective agent for patterning can be cited. In addition, the thermoplastic resin layer can be composed of, for example, a UV strippable resin layer or a heat strippable resin layer, and is preferably composed in a manner having at least one selected from the group consisting of a photosensitive resin layer, a UV strippable resin layer and a heat strippable resin layer.

[0123] The support substrate 28 can be, for example, formed by arranging a thin film or sheet support substrate 28 on the solder resist layer 26 and the protective coating 27, and laminating and crimping the laminate. In addition, when the thermoplastic resin layer is composed of a photosensitive resin layer, as a process for laminating the photosensitive resin layer, for example, a process for arranging a photosensitive resin layer on the solder resist layer 26 and the protective coating 27, laminating, and then exposing and curing the entire surface of the photosensitive resin layer. By exposing and curing the entire surface of the photosensitive resin layer, the adhesion to the solder resist layer 26 and the protective coating 27 is increased. In the case where the thermoplastic resin layer is composed of a UV strippable resin layer or a heat strippable resin layer, as a process for laminating the UV strippable resin layer or the heat strippable resin layer, for example, a process for laminating the UV strippable resin layer or the heat strippable resin layer can be included. The thickness of the support substrate 28 is appropriately set as desired and is not particularly limited, but can be, for example, 1 μm or more, preferably 1 μm or more and 50 μm or less, and more preferably 1 μm or more and 30 μm or less.

[0124] After the supporting substrate lamination step, for example Fig. 9 As shown in (B), similarly to the first manufacturing method and the second manufacturing method, at least the core resin layer 11 is separated and removed in the stripping unit (core resin layer separation and removal step). After the core resin layer separation and removal step, for example, Fig.10 As shown in (C), similarly to the first manufacturing method and the second manufacturing method, the remaining first metal layer 12 and the diffusion prevention layer 13 are removed (first metal layer / diffusion prevention layer removal step).

[0125] After the first metal layer / diffusion prevention layer removal step, for example Fig.10As shown in (D), the support substrate 28 is removed to obtain a coreless substrate 30 (support substrate removal step). The means for removing the support substrate 28 is not particularly limited and can be appropriately selected according to the material of the support substrate 28. The support substrate 28 can be removed, for example, by a chemical solution such as an aqueous sodium hydroxide solution, by a laser, or by plasma treatment. For example, in the case of a UV peelable resin layer, it can be removed by irradiating light in the ultraviolet region to peel it off, and in the case of a thermal peelable resin layer, it can be removed by heating to peel it off.

[0126] As described above, according to the present embodiment, the first metal layer 12 having the stripping unit is provided on at least one side of the core resin layer 11, and the diffusion prevention layer 13 is provided on the surface of the first metal layer 12 on the opposite side to the core resin layer 11. Therefore, after the core resin layer 11 is separated and removed in the stripping unit, when the remaining first metal layer 12 is removed by etching, the diffusion prevention layer 13 can be used as an etching stopper. Therefore, the remaining first metal layer 12 can be easily removed. In addition, mutual diffusion of constituent elements of the first metal layer 12 and the protective plating layer 15 formed thereon can be suppressed, so that a good protective plating layer 15 can be formed.

[0127] Furthermore, if the thickness of the first metal layer 12 from the end face on the diffusion prevention layer 13 side to the stripping unit is greater than 6 μm, after the wiring substrate 20A is formed on the first metal layer 12, the wiring substrate 20A can be reinforced to suppress damage when the core resin layer 11 is separated and removed in the stripping unit.

[0128] [Modifications]

[0129] In the first embodiment, the diffusion prevention layer 13 is provided on the surface of the first metal layer 12 opposite to the core resin layer 11, and the anti-plating layer 14 is provided on the surface of the diffusion prevention layer 13 opposite to the first metal layer 12. However, for example, Fig.11 As shown, a diffusion prevention layer 13 and a plating resistance layer 14 are simultaneously provided on the surface of the first metal layer 12 on the opposite side to the core resin layer 11. That is, it is also possible to have a first metal layer 12 provided on at least one side of the core resin layer 11 and having a peeling unit, and a diffusion prevention layer 13 and a plating resistance layer 14 provided on the surface of the first metal layer 12 on the opposite side to the core resin layer 11, and further, a protective plating layer 15 is provided on the opposite side of the diffusion prevention layer 13 to the first metal layer 12. That is, the diffusion prevention layer 13 is in contact with the first metal layer 12 and is formed in a region where the plating resistance layer 14 is not formed, and the protective plating layer 15 is formed on the opposite side of the diffusion prevention layer 13 to the first metal layer 12 in the region where the plating resistance layer is not formed.

[0130] The laminate 10 can be manufactured, for example, as follows. First, a support 10A is prepared in the same manner as in the first embodiment (support preparation step; see Figure 2 (A)), such as Fig.12 As shown in (A), the plating resist 14 is formed on the surface of the first metal layer 12 on the opposite side to the core resin layer 11 in the same manner as in the first embodiment (plating resist forming step). Fig.12 As shown in (B), similarly to the first embodiment, the diffusion prevention layer 13 is formed on the surface of the first metal layer 12 on the opposite side to the core resin layer 11 in the region where the plating resist 14 is not formed (diffusion prevention layer forming step). Fig.12 As shown in (C), similarly to the first embodiment, the protective plating layer 15 is formed on the side of the diffusion prevention layer 13 opposite to the first metal layer 12 (protective plating layer forming step).

[0131] The laminated body 10 of the modified example can also be used when manufacturing the wiring substrate with support 20 and the coreless substrate 30 in the same manner as the first embodiment, and the same effects as those of the first embodiment can be obtained.

[0132] Example

[0133] Hereinafter, the present embodiment and the modified examples will be specifically described using examples, but the present embodiment and the modified examples are not limited to these examples at all.

[0134] [Example 1]

[0135] <Support preparation step> (refer to Figure 2 (A)

[0136] A prepreg (thickness 0.100 mm, manufactured by Mitsubishi Gas Chemical Co., Ltd., product name: GHPL-830NS ST56) prepared by impregnating glass cloth (glass fiber) with bismaleimide triazine resin (BT resin) to form a B-stage was used as the core resin layer 11, and a copper foil with a carrier copper foil having a thickness of 18 μm (copper foil, thickness 5 μm, manufactured by Mitsui Mining and Smelting Co., Ltd., product name: MT18SD-H-T5) was arranged on both sides of the core resin layer 11 so that the carrier copper foil side was in contact with the core resin layer 11 as the first metal layer 12. Vacuum pressing was performed under the conditions of temperature 220±2° C., pressure 3±0.2 MPa, and holding time 60 minutes to produce a support body 10A having the first metal layer 12 provided on both sides of the core resin layer 11. The carrier copper foil was the carrier 12A, and the copper foil was the metal foil 12B.

[0137] <Diffusion prevention layer formation step> (refer to Figure 2 (B)

[0138] A nickel plating layer is formed by electrolytic plating on the surface of the first metal layer 12 on the opposite side to the core resin layer 11 as the diffusion prevention layer 13. The thickness of the diffusion prevention layer 13 is 3 μm to 10 μm.

[0139] <Resist layer forming step> (refer to Figure 2 (C)

[0140] A 25 μm thick dry film protective agent RD-1225 (manufactured by Showa Denko Materials Co., Ltd., product name) is laminated on the surface of the diffusion prevention layer 13 opposite to the first metal layer 12 at a temperature of 110±10° C. and a pressure of 0.50±0.02 MPa. After the circuit pattern is baked on the dry film protective agent using a parallel exposure machine, the dry film protective agent is developed using a 1% sodium carbonate aqueous solution to form a plating resist 14.

[0141] <Protective plating layer forming process> (refer to Figure 2 (D)

[0142] A gold plating layer 15A and a nickel plating layer 15B are sequentially laminated by electrolytic plating in a region of the diffusion prevention layer 13 opposite to the first metal layer 12 where the plating resist 14 is not provided, thereby forming a protective plating layer 15. The thickness of the gold plating layer 15A is 0.05 μm to 0.1 μm. The thickness of the nickel plating layer 15B is 3 μm to 10 μm.

[0143] <First wiring conductor forming step> (refer to Figure 3 (A)

[0144] The first wiring conductor 21 is formed by pattern electrolytic copper plating (electrolytic copper plating) with a thickness of 5 μm to 15 μm in a region of the protective plating layer 15 on the opposite side of the diffusion prevention layer 13 where the anti-plating layer 14 is not provided, using a copper sulfate plating line with a copper sulfate concentration of 60 g / L to 80 g / L and a sulfuric acid concentration of 150 g / L to 200 g / L.

[0145] <Resist Removal Process> (Refer to Figure 6 (A)

[0146] After the first wiring conductor 21 is formed, the plating resist 14 is stripped away using an amine-based resist stripping solution.

[0147] <First Insulation Layer Forming Step / Second Wiring Conductor Forming Step> (See Figure 6 (B)

[0148] Next, in order to improve the adhesion with the first insulating layer 22, the surface of the first wiring conductor 21 was roughened using copper surface roughening liquid CZ-8101 (manufactured by MEC Co., Ltd., product name). Next, a copper foil with a carrier copper foil with a resin layer (copper foil thickness 2 μm, carrier copper foil thickness 18 μm, resin layer thickness 0.015 mm: manufactured by Mitsubishi Gas Chemical Co., Ltd., product name: CRS381NSI) was arranged on the first wiring conductor 21 and the diffusion prevention layer 13 so that the resin layer was in contact with the first wiring conductor 21, and vacuum pressing was performed under the conditions of pressure 3±0.2 MPa, temperature 220±2° C., and holding time 60 minutes. Thereafter, the carrier copper foil was peeled off, and the first insulating layer 22 and the second metal layer with a thickness of 2 μm were laminated on the first wiring conductor 21.

[0149] Next, a carbon dioxide laser processing machine ML605GTWIII-5200U (manufactured by Mitsubishi Electric Corporation, product name) is used to irradiate the surface of the second metal layer with a carbon dioxide laser, and a hole is opened on the second metal layer and the first insulating layer 22 to form a first non-through hole 22A reaching the first wiring conductor 21. Next, a desmear treatment is performed using an aqueous sodium permanganate solution at a temperature of 80±5°C and a concentration of 55±10g / L. Next, chemical copper plating is performed to a thickness of 0.4μm to 0.8μm, and then electrolytic copper plating is performed to a thickness of 5μm to 20μm, forming a first connecting through hole 22B for connecting the first wiring conductor 21 and the second metal layer on the inner wall of the first non-through hole 22A, increasing the thickness of the second metal layer and performing surface adjustment.

[0150] Next, a dry film protective agent LDF515F (manufactured by Nikko Materials Co., Ltd., product name) is laminated on the second metal layer at a temperature of 110±10°C and a pressure of 0.50±0.02MPa. Then, a negative mask is attached, the circuit pattern is baked using a parallel exposure machine, and the dry film protective agent is developed using a 1% sodium carbonate aqueous solution to form an anti-etching layer. Next, after the second metal layer without the anti-etching layer is etched away using a cupric chloride aqueous solution, the dry film protective agent is removed using a sodium hydroxide aqueous solution to form a second wiring conductor 23.

[0151] <Lamination process> (refer to Figure 6 (C)

[0152] After forming the second wiring conductor 23, the same process as the first insulating layer forming process and the second wiring conductor forming process is repeated to form the second insulating layer 24 and the third wiring conductor 25, thereby forming a wiring substrate 20 with a support having a laminated structure with three layers of wiring conductors.

[0153] <Solder Resist Formation Process> (See Figure 7 (D)

[0154] After forming the second insulating layer 24 and the third wiring conductor 25, the solder resist layer 26 is formed thereon to partially expose the third wiring conductor 25. The solder resist layer 26 is formed to have a thickness of 10 μm from the upper surface of the third wiring conductor 25 to the upper surface of the solder resist layer 26.

[0155] <Plating finishing process> (refer to Figure 7 (E)

[0156] After forming the solder resist layer 26, a nickel plating layer 27A and a gold plating layer 27B are sequentially formed as a protective plating layer 27 by electrolytic plating on the third wiring conductor 25 exposed from the solder resist layer 26. The thickness of the nickel plating layer 27A is 3 μm to 5 μm. The thickness of the gold plating layer 27B is 0.05 μm to 0.1 μm. Thus, the wiring substrate 20 with a support is obtained.

[0157] <Core resin layer separation and removal step, first metal layer / diffusion prevention layer removal step> (refer to Figure 8 (F)(G)

[0158] A physical force is applied to the boundary between the metal foil 12B of the first metal layer 12 of the obtained wiring substrate with support 20 and the carrier 12A to peel off and remove at least the core resin layer 11. Next, the remaining first metal layer 12 (specifically, the metal foil 12B) and the diffusion prevention layer 13 are removed using a cupric chloride aqueous solution to obtain a set of coreless substrates 30.

[0159] In the coreless substrate 30 obtained in Example 1, no corrosion of the gold plating layer 15A in the protective plating layer 15 was observed, and a good coreless substrate 30 was obtained.

[0160] [Example 2]

[0161] A set of coreless substrates 30 was obtained by the same process as in Example 1 except that a tin-plated layer was formed as the diffusion prevention layer 13. In Example 2, no corrosion of the gold-plated layer 15A in the protective plating layer 15 was observed, and a good coreless substrate 30 was obtained.

[0162] [Example 3]

[0163] The surface of the copper foil with a carrier copper foil (copper foil, thickness 5 μm: manufactured by Mitsui Mining & Smelting Co., Ltd., product name: MT18SD-H-T5) with a thickness of 18 μm used in Example 1 was electrolytically plated to produce a copper foil with a carrier copper foil with a thickness increased to 10 μm. The same process as in Example 1 was performed except that the thickness of the metal foil 12B in the first metal layer 12 was 10 μm using this copper foil with a carrier copper foil to obtain a set of coreless substrates 30. That is, the thickness of the first metal layer 12 from the end surface on the side of the diffusion prevention layer 13 to the peeling unit was made to be 10 μm. In Example 3, no corrosion of the gold plating layer 15A in the protective plating layer 15 was found, and a good coreless substrate 30 could be obtained. In addition, since the thickness of the first metal layer 12 from the end surface on the side of the diffusion prevention layer 13 to the peeling unit is 6 μm or more, a high yield is obtained in the core resin layer separation and removal process.

[0164] [Comparative Example 1]

[0165] A set of coreless substrates were obtained by carrying out the same steps as in Example 1 except that the diffusion prevention layer was not formed. However, corrosion of the gold plating layer in the protective plating layer was observed.

[0166] [Comparative Example 2]

[0167] A set of coreless substrates was obtained by the same process as in Example 1 except that the diffusion prevention layer was not formed and the copper foil with carrier produced in Example 3 was used so that the thickness of the metal foil in the first metal layer was 10 μm. However, corrosion of the gold plating layer in the protective plating layer was found.

[0168] (Characteristics evaluation)

[0169] The properties of Examples 1, 2, 3 and Comparative Examples 1 and 2 were measured by the following methods.

[0170] [Corrosion evaluation of protective coating]

[0171] In order to confirm the corrosion inhibition effect of the protective plating 15 brought by the diffusion prevention layer 13, the protective plating 15 of the obtained coreless substrate 30 was observed. The element analysis function of the scanning electron microscope (JSM-IT700HR, JEOL Ltd.) was used to adjust the magnification to 1,000 times for observation. The area of ​​the protective plating 15 exposed from the first insulating layer 22 functioning as a solder resist layer was set to 100%. If the area covered by the elements from the protective plating is more than 90%, it means that there is no corrosion, and if it is less than 90%, it means that there is corrosion. The results obtained are shown in Table 1.

[0172] [Evaluation of Yield of Core Resin Layer Separation and Removal Process]

[0173] In the core resin layer separation and removal step, the number of broken wiring boards observed was counted for all the wiring boards, and the yield was calculated by the following formula. The obtained results are shown in Table 1.

[0174] [Total quantity - Number of observed damages] / Total quantity × 100

[0175] [Table 1]

[0176]

[0177] That is, according to this embodiment, by providing the diffusion prevention layer 13, the corrosion of the protective plating layer can be suppressed, and a good coreless substrate 30 can be obtained. In addition, if the thickness of the first metal layer 12 from the end surface on the diffusion prevention layer 13 side to the peeling unit is set to 6 μm or more, the damage in the core resin layer separation and removal process can be suppressed, and a high yield can be obtained.

[0178] Industrial Applicability

[0179] It can be used for printed wiring boards and package substrates for mounting semiconductor devices.

[0180] Description of Reference Numerals

[0181] 10... laminated body, 10A... support body, 11... core resin layer, 12... first metal layer, 12A... carrier, 12B... metal foil, 13... diffusion prevention layer, 14... anti-plating layer, 15... protective plating layer, 15A... gold plating layer, 15B... nickel plating layer, 20... wiring substrate with support body, 20A... wiring substrate, 21... first wiring conductor, 22... first insulating layer, 22A... first non-through hole, 22B... first connecting through hole, 23... second wiring conductor, 24... (m+1)th insulating layer, 24A... (m+1)th non-through hole, 24B... (m+1)th connecting through hole, 25... (m+2)th wiring conductor, 26... solder resist layer, 27... protective plating layer, 27A... nickel plating layer, 27B... gold plating layer, 28... support substrate, 30... coreless substrate.

Claims

1. A laminate comprising: Core resin layer, a first metal layer provided on at least one surface side of the core resin layer and having a peeling unit, and a diffusion prevention layer provided on a surface of the first metal layer opposite to the core resin layer.

2. The laminate according to claim 1, wherein The diffusion prevention layer has a plating resist on a surface opposite to the first metal layer.

3. The laminate according to claim 2, wherein: A protective plating layer is provided in a region of the diffusion prevention layer on the side opposite to the first metal layer where the plating resist is not provided.

4. The laminate according to claim 1, wherein The diffusion prevention layer and the plating resist are both provided on the surface of the first metal layer opposite to the core resin layer.

5. The laminate according to claim 4, wherein A protective plating layer is provided on the side of the diffusion prevention layer opposite to the first metal layer.

6. The laminate according to claim 1, wherein The diffusion prevention layer includes at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium.

7. The laminate according to claim 1, wherein The thickness of the first metal layer from the end surface on the diffusion prevention layer side to the peeling unit is 6 μm or more.

8. A method for manufacturing a coreless substrate, comprising: a support body preparation step of preparing a support body having a core resin layer and a first metal layer provided on at least one side of the core resin layer and having a peeling unit, and The diffusion prevention layer forming step is to form a diffusion prevention layer on a surface of the first metal layer opposite to the core resin layer.

9. The method for manufacturing a coreless substrate according to claim 8, wherein: After the diffusion prevention layer forming step, a plating resist forming step of forming a plating resist on a surface of the diffusion prevention layer opposite to the first metal layer is included.

10. The method for manufacturing a coreless substrate according to claim 9, wherein: After forming the plating resist, a protective plating layer forming step of forming a protective plating layer in a region of the diffusion prevention layer opposite to the first metal layer where the plating resist is not provided is included.

11. The method for manufacturing a coreless substrate according to claim 8, wherein: Before the diffusion prevention layer forming step, a plating resist forming step of forming a plating resist on a surface of the first metal layer opposite to the core resin layer is included. The diffusion prevention layer is formed in a region of the surface of the first metal layer on the opposite side to the core resin layer where the plating resist is not formed.

12. The method for manufacturing a coreless substrate according to claim 11, wherein: After the diffusion prevention layer forming step, a protective plating layer forming step of forming a protective plating layer on the side of the diffusion prevention layer opposite to the first metal layer is included.

13. The method for manufacturing a coreless substrate according to claim 8, wherein: The diffusion prevention layer includes at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium.

14. The method for manufacturing a coreless substrate according to claim 8, wherein: The thickness of the first metal layer from the end surface on the diffusion prevention layer side to the peeling unit is 6 μm or more.

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