WO2024043196A1

WO2024043196A1 - Laminate, and method for manufacturing coreless substrate

Info

Publication number: WO2024043196A1
Application number: PCT/JP2023/029908
Authority: WO
Inventors: 慎也喜多村; 和晃川下; 隼斗中川; 公幸野原; 豪志信國
Original assignee: Ｍｇｃエレクトロテクノ株式会社; 米沢ダイヤエレクトロニクス株式会社
Priority date: 2022-08-26
Filing date: 2023-08-18
Publication date: 2024-02-29
Also published as: TW202410319A

Abstract

This 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 to the core resin layer (11), and a plating resist (14) provided on the surface of the diffusion prevention layer (13) on the opposite side to the first metal layer (12). A protective plating layer (15) is provided on the side of the diffusion prevention layer (13) opposite to the first metal layer (12), in regions where the plating resist (14) is not provided.

Description

Method for manufacturing laminate and coreless substrate

The present invention relates to a laminate having a first metal layer provided on at least one side of a core resin layer and provided with a peeling means, and a method for manufacturing a coreless substrate using the laminate.

In recent years, the functionality and miniaturization of semiconductor packages widely used in electronic equipment, communication equipment, personal computers, etc. have been accelerating. Accordingly, there is a demand for thinner printed wiring boards and package substrates for mounting semiconductor elements in semiconductor packages. As a thinned printed wiring board and a package substrate for mounting semiconductor elements, for example, after a wiring board is formed by laminating a first metal layer having a peeling means, an insulating layer, and a wiring conductor on a core resin layer, A so-called coreless board in which a core resin layer is peeled off from a wiring board is known (for example, see Patent Document 1).

International Publication WO2020/121652 Publication

However, in such a coreless board, when removing the first metal layer remaining on the wiring board by etching after separating the core resin layer, it is difficult to control, and excessive etching may occur, or conversely, the first metal layer remaining on the wiring board may be removed by etching. There was a problem that there were cases where this was insufficient. Furthermore, if a protective plating layer is formed on the first metal layer and a wiring conductor is formed on top of the protective plating layer, the constituent elements of the first metal layer and the protective plating layer will diffuse into each other and the protective plating layer will be protected. There was also the problem that the plating layer corroded.

The present invention has been made based on these problems, and provides a laminated layer that allows the first metal layer to be easily removed after separating the core resin layer and that also allows the formation of a good protective plating layer. The present invention aims to provide a method for manufacturing a coreless substrate and a coreless substrate.

The invention is as follows.
[1]
a core resin layer;
a first metal layer provided on at least one side of the core resin layer and provided with a peeling means;
a diffusion prevention layer provided on a surface of the first metal layer opposite to the core resin layer;
A laminate having.
[2]
The laminate according to [1], wherein a plating resist is provided on a surface of the diffusion prevention layer opposite to the first metal layer.
[3]
The laminate according to [2], which has a protective plating layer in a region where the plating resist is not provided on the opposite side of the first metal layer of the diffusion prevention layer.
[4]
The laminate according to [1], which has a plating resist together with the diffusion prevention layer on the surface of the first metal layer opposite to the core resin layer.
[5]
The laminate according to [4], further comprising a protective plating layer on a side of the diffusion prevention layer opposite to the first metal layer.
[6]
The laminate according to [1], wherein the diffusion prevention layer contains 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 [1], wherein the thickness from the end surface of the first metal layer on the diffusion prevention layer side to the peeling means is 6 μm or more.
[8]
a support preparation step of preparing a support having a core resin layer and a first metal layer provided on at least one side of the core resin layer and provided with a peeling means;
a diffusion prevention layer forming step of forming a diffusion prevention layer on the surface of the first metal layer opposite to the core resin layer;
A method for manufacturing a coreless board, including:
[9]
The method for producing a coreless substrate according to [8], which includes a plating resist forming step of forming a plating resist on a surface of the diffusion preventing layer opposite to the first metal layer after the diffusion preventing layer forming step. .
[10]
After forming the plating resist, a protective plating layer forming step of forming a protective plating layer in a region where the plating resist is not provided on the opposite side of the first metal layer of the diffusion prevention layer, [ 9], the method for manufacturing a coreless substrate.
[11]
Before the diffusion prevention layer forming step, a plating resist forming step of forming a plating resist on the surface of the first metal layer opposite to the core resin layer,
The method for manufacturing a coreless substrate according to [8], wherein the diffusion prevention layer is formed in a region where a plating resist is not formed on a surface of the first metal layer opposite to the core resin layer.
[12]
The method for producing a coreless substrate according to [11], which includes a protective plating layer forming step of forming a protective plating layer on the side of the diffusion preventing layer opposite to the first metal layer after the diffusion preventing layer forming step. .
[13]
Production of the coreless substrate according to [8], wherein the diffusion prevention layer contains at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium. Method.
[14]
The method for manufacturing a coreless substrate according to [8], wherein the thickness from the end surface of the first metal layer on the diffusion prevention layer side to the peeling means is 6 μm or more.

According to the present invention, the first metal layer provided with a peeling means is provided on at least one side of the core resin layer, and the diffusion prevention layer is provided on the side of the first metal layer opposite to the core resin layer. Since the diffusion prevention layer is provided, the diffusion prevention layer can be used as an etching stopper when the remaining first metal layer is removed by etching after the core resin layer is separated and removed by the peeling means. Therefore, the remaining first metal layer can be easily removed. Moreover, since the constituent elements of the first metal layer and the protective plating layer formed thereon can be suppressed from diffusing into each other, a good protective plating layer can be formed.

Furthermore, if the thickness from the end surface of the first metal layer on the diffusion prevention layer side to the peeling means is 6 μm or more, the core resin layer can be removed by the peeling means after forming the wiring board on the first metal layer. When separating and removing, the wiring board can be reinforced and damage can be suppressed.

FIG. 1 is a diagram showing the configuration of a laminate according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating steps in a method for manufacturing the laminate shown in FIG. 1. FIG. FIG. 2 is a diagram illustrating steps of a first manufacturing method of a wiring board with a support and a coreless board using the laminate shown in FIG. 1. FIG. FIG. 4 is a diagram showing a process subsequent to FIG. 3; FIG. 5 is a diagram showing a process subsequent to FIG. 4; FIG. 2 is a diagram illustrating steps of a second manufacturing method for a wiring board with a support and a coreless board using the laminate shown in FIG. 1. FIG. FIG. 7 is a diagram showing a process subsequent to FIG. 6; FIG. 8 is a diagram showing a process subsequent to FIG. 7; FIG. 2 is a diagram illustrating steps of a third manufacturing method for a wiring board with a support and a coreless board using the laminate shown in FIG. 1. FIG. 10 is a diagram showing a process following FIG. 9. FIG. It is a figure showing the structure of the laminated body concerning the modification of the present invention. FIG. 12 is a diagram illustrating steps in the method for manufacturing the laminate shown in FIG. 11.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as "embodiments") will be described in detail, but the present invention is not limited thereto, and various modifications may be made without departing from the gist thereof. It is possible.

[First embodiment]
FIG. 1 shows the configuration of a laminate 10 according to a first embodiment of the present invention. This laminate 10 includes a core resin layer 11, a first metal layer 12 provided on at least one side of the core resin layer 11 and provided with a peeling means, and a core resin layer 11 of the first metal layer 12. and a plating resist 14 provided on the surface of the diffusion prevention layer 13 opposite to the first metal layer 12. On the side opposite to the first metal layer 12 of 13, a protective plating layer 15 may be provided in a region where the plating resist 14 is not provided. This laminate 10 can be used, for example, when manufacturing a wiring board 20 with a support (see, for example, FIGS. 3 and 4) and a coreless board 30 (see, for example, FIG. 5).

The wiring board 20 with a support includes a support 10A in which the first metal layer 12 is provided on at least one side of the core resin layer 11, and a wiring board 20A provided on the first metal layer 12. (For example, see FIGS. 3 and 4). The wiring board 20 with a support is also called a printed wiring board with a support or a package board with a support, and includes a printed wiring board or a package board for mounting a semiconductor element as the wiring board 20A. A printed wiring board or a package substrate for mounting a semiconductor element constitutes an electronic component mounting board by mounting an electronic component element such as a semiconductor element, for example. The wiring board 20A is not limited to one on which a semiconductor element is mounted, but may be one on which a surface-mounted electronic component element such as an LED (Light Emitting Diode) element, a capacitor, a resistor, a coil, etc. is mounted. The coreless board 30 is obtained by separating and removing the support body 10A from the support-attached wiring board 20 (for example, see FIG. 5).

<Structure of laminate>
(core resin layer)
The core resin layer 11 is for increasing the rigidity of the wiring board 20A, suppressing warping, and improving handling properties in the manufacturing process of the wiring board 20A or the mounting process of semiconductor elements. Although FIG. 1 shows a case where the first metal layer 12 is provided on one side of the core resin layer 11, the first metal layer 12 may be provided on both sides of the core resin layer 11. You may also do so. The core resin layer 11 is not particularly limited, but may be made of, for example, a prepreg made by impregnating a base material such as glass cloth with an insulating resin material (insulating material) such as a thermosetting resin, or an insulating film. It can be constructed from materials etc. The thickness of the core resin layer 11 is not particularly limited as it is appropriately set as desired, but is preferably 1 μm or more, for example. This is because if the thickness of the core resin layer 11 is less than 1 μm, the wiring board 20A may be defective in molding.

"Prepreg" is made by impregnating or coating a base material with an insulating material such as a resin composition. The base material is not particularly limited, and well-known materials can be used as appropriate. Examples of the material constituting the base material 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 base material is not particularly limited, but for example, those having shapes such as woven fabric, nonwoven fabric, roving, chopped strand mat, surfacing mat, etc. can be used as appropriate. The material and shape of the base material are selected depending on the intended use and performance of the molded article, and if necessary, it is also possible to use one or more materials and shapes.

The thickness of the base material is not particularly limited as long as the thickness of the core resin layer 11 falls within the above-mentioned range. In addition, as a base material, one that has been surface-treated with a silane coupling agent, etc., or one that has been mechanically opened can be used, and these base materials are suitable in terms of heat resistance, moisture resistance, and processability. It is.

The insulating material is not particularly limited, and any known resin composition used as an insulating material for printed wiring boards or package substrates for mounting semiconductor elements can be appropriately selected and used. As the resin composition, a thermosetting resin having good heat resistance and chemical resistance can be used as a base. Thermosetting resins are not particularly limited, and include, for example, polyimide resins, phenol resins, epoxy resins, cyanate resins, maleimide resins, modified polyphenylene ethers, bismaleimide triazine resins, isocyanate resins, benzocyclobutene resins, and vinyl resins. It will be done. These thermosetting resins may be used alone or in combination of two or more.

The polyimide resin is not particularly limited, and commercially available products can be appropriately selected and used. For example, a solvent-soluble polyimide resin synthesized by the manufacturing method described in JP-A-2005-15629 or a block copolymerized polyimide resin can be used. Examples of block copolymer polyimide resins include block copolymer polyimide resins described in International Publication No. WO2010-073952. Specifically, the block copolymerized polyimide resin consists of a structure A in which an imide oligomer consisting of a second structural unit is bonded to the end of an imide oligomer consisting of a first structural unit, and a structure A consisting of a second structural unit. It is not particularly limited as long as it is a copolymerized polyimide resin having a structure in which structure B, in which an imide oligomer consisting of a first structural unit is bonded to the end of the imide oligomer, is alternately repeated. Note that the second structural unit is different from the first structural unit. These block copolymerized polyimide resins are produced by reacting a tetracarboxylic dianhydride and a diamine in a polar solvent to form an imide oligomer, and then reacting the tetracarboxylic dianhydride with another diamine or another tetracarboxylic dianhydride. It can be synthesized by a sequential polymerization reaction in which an acid dianhydride and a diamine are added and imidized. These polyimide resins may be used alone or in combination of two or more.

The phenol resin is not particularly limited, and one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) per molecule is used. ) Generally known compounds or resins can be used as long as they have a phenolic hydroxy group. For example, bisphenol A type phenol resin, bisphenol E type phenol resin, bisphenol F type phenol resin, bisphenol S type phenol resin, phenol novolak resin, bisphenol A novolac type phenol resin, glycidyl ester type phenol resin, aralkyl novolak type phenol resin, biphenyl Aralkyl type phenolic resin, cresol novolac type phenolic resin, polyfunctional phenolic resin, naphthol resin, naphthol novolak resin, polyfunctional naphthol resin, anthracene type phenolic resin, naphthalene skeleton modified novolak type phenolic resin, phenol aralkyl type phenolic resin, naphthol aralkyl type Examples include phenolic resins, dicyclopentadiene type phenolic resins, biphenyl type phenolic resins, alicyclic phenolic resins, polyol type phenolic resins, phosphorus-containing phenolic resins, and hydroxyl group-containing silicone resins. These phenolic resins may be used alone or in combination of two or more.

Among thermosetting resins, epoxy resins have excellent heat resistance, chemical resistance, and electrical properties, and are relatively inexpensive, so they can be suitably used as insulating materials. The epoxy resin has one or more (preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) epoxy groups in one molecule. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phenol novolac type epoxy resin. , cresol novolak type epoxy resin, bisphenol A novolac type epoxy resin, diglycidyl ether of biphenol, diglycidyl ether of naphthalene diol, diglycidyl ether of phenols, diglycidyl ether of alcohol, and Examples thereof include alkyl substituted products, halides, and hydrogenated products. These epoxy resins may be used alone or in combination of two or more. In addition, the curing agent used with this epoxy resin can be used without limitation as long as it cures the epoxy resin. For example, polyfunctional phenols, polyfunctional alcohols, amines, imidazole compounds, acid anhydrides, organic Examples include phosphorus compounds and halides thereof. These epoxy resin curing agents may be used alone or in combination of two or more.

Cyanate resin is a resin that produces a cured product having triazine rings as repeating units when heated, and the cured product has excellent dielectric properties. Therefore, it is particularly suitable when high frequency characteristics are required. The cyanate resin has one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) cyanato groups per molecule ( There are no particular limitations on the compound or resin as long as it has an aromatic moiety in its molecule substituted with a cyanate ester group, but examples include 2,2-bis(4-cyanatophenyl)propane, bis(4-cyanatophenyl)propane, phenyl)ethane, 2,2-bis(3,5dimethyl-4-cyanatophenyl)methane, 2,2-(4-cyanatophenyl)-1,1,1,3,3,3-hexafluoropropane , α,α'-bis(4-cyanatophenyl)-m-diisopropylbenzene, cyanate esters of phenol novolak and alkylphenol novolak, and the like. Among these, 2,2-bis(4-cyanatophenyl)propane is preferred because it has a particularly good balance between the dielectric properties and curability of the cured product and is inexpensive. One type of cyanate resin such as these cyanate ester compounds may be used alone, or two or more types may be used in combination. Further, a portion of the cyanate ester compound may be oligomerized into a trimer or a pentamer in advance.

Furthermore, a curing catalyst and a curing accelerator can also be used together with the cyanate resin. As the curing catalyst, for example, metals such as manganese, iron, cobalt, nickel, copper, and zinc can be used. Specifically, organic metal salts such as 2-ethylhexanoate and octylate, and acetylacetone Examples include organometallic complexes such as complexes. One type of curing catalyst may be used alone, or two or more types may be used in combination.

Furthermore, it is preferable to use phenols as the curing accelerator, such as monofunctional phenols such as nonylphenol and paracumylphenol, bifunctional phenols such as bisphenol A, bisphenol F, and bisphenol S, or phenol novolak and cresol novolak. Polyfunctional phenols and the like can be used. One type of curing accelerator may be used alone, or two or more types may be used in combination.

The maleimide resin has one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) maleimide groups in one molecule. Generally known compounds or resins can be used as long as they have the following properties. For example, 4,4-diphenylmethanebismaleimide, phenylmethanemaleimide, m-phenylenebismaleimide, 2,2-bis(4-(4-maleimidophenoxy)-phenyl)propane, 3,3-dimethyl-5,5-diethyl -4,4-diphenylmethane bismaleimide, 4-methyl-1,3-phenylenebismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 4,4-diphenyl ether bismaleimide, 4,4 - Diphenylsulfone bismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, 1,3-bis(4-maleimidophenoxy)benzene, polyphenylmethanemaleimide, novolak-type maleimide, biphenylaralkyl-type maleimide, and these maleimide compounds or a prepolymer of a maleimide compound and an amine compound, but is not particularly limited. These maleimide resins may be used alone or in combination of two or more.

Modified polyphenylene ether is useful from the viewpoint of being able to improve the dielectric properties of a cured product. Examples of modified polyphenylene ethers include poly(2,6-dimethyl-1,4-phenylene) ether, alloyed polymers of poly(2,6-dimethyl-1,4-phenylene) ether and polystyrene, and poly(2,6-dimethyl-1,4-phenylene) ether. , 6 dimethyl-1,4-phenylene) ether and styrene-butadiene copolymer, alloyed polymer of poly(2,6-dimethyl-1,4-phenylene) ether and styrene-maleic anhydride copolymer, poly Alloyed polymer of (3,6-dimethyl-1,4-phenylene) ether and polyamide, alloyed polymer of poly(2,6-dimethyl-1,4-phenylene) ether and styrene-butadiene-acrylonitrile copolymer, Examples include oligophenylene ether. In addition, in order to impart reactivity and polymerizability to polyphenylene ether, functional groups such as amine groups, epoxy groups, carboxyl groups, and styryl groups are introduced at the end of the polymer chain, and amine groups and epoxy groups are introduced into the side chains of the polymer chain. , carboxyl group, styryl group, methacrylic group, etc. may be introduced.

The isocyanate resin is not particularly limited, and examples thereof include isocyanate resins obtained by a dehydrohalogenation reaction between phenols and cyanogen halides. Examples of the isocyanate resin include 4,4'-diphenylmethane diisocyanate MDI, polymethylene polyphenyl polyisocyanate, tolylene diisocyanate, and hexamethylene diisocyanate. These isocyanate resins may be used alone or in combination of two or more.

The benzocyclobutene resin is not particularly limited as long as it contains 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.

The vinyl resin is not particularly limited as long as it is a polymer or copolymer of vinyl monomers. Vinyl monomers are not particularly limited, and include, for example, (meth)acrylic acid ester derivatives, vinyl ester derivatives, maleic acid diester derivatives, (meth)acrylamide derivatives, styrene derivatives, vinyl ether derivatives, vinyl ketone derivatives, olefin derivatives, maleimide derivatives, (Meth)acrylonitrile is mentioned. These vinyl resins may be used alone or in combination of two or more.

A thermoplastic resin can also be blended into the resin composition used as the insulating material, taking dielectric properties, impact resistance, film processability, etc. into consideration. The thermoplastic resin is not particularly limited, and examples thereof include fluororesin, polycarbonate, polyetherimide, polyetheretherketone, polyacrylate, polyamide, polyamideimide, polybutadiene, and the like. One type of thermoplastic resin may be used alone, or two or more types may be used in combination. Further, the fluororesin is not particularly limited, and examples thereof include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, and polyvinyl fluoride. These fluororesins may be used alone or in combination of two or more.

Among thermoplastic resins, polyamide-imide resin is useful because it has excellent moisture resistance and is also a good adhesive for metals. The raw materials for the polyamide-imide resin are not particularly limited, but the acidic component includes trimellitic anhydride and trimellitic anhydride monochloride, and the amine component includes metaphenylenediamine, paraphenylenediamine, , 4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, bis[4-(aminophenoxy)phenyl]sulfone, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, and the like. The polyamide-imide resin may be modified with siloxane to improve drying properties, and in this case, siloxane diamine can be used as the amino component. When considering film processability, it is preferable to use a polyamide-imide resin having a molecular weight of 50,000 or more.

A filler may be mixed in the resin composition used as the insulating material. Fillers include, but are not particularly limited to, metal oxides (including hydrates) such as alumina, white carbon, titanium white, titanium oxide, zinc oxide, magnesium oxide, and zirconium oxide, aluminum hydroxide, boehmite, Metal hydroxides such as magnesium hydroxide, silicas such as natural silica, fused silica, synthetic silica, amorphous silica, Aerosil, hollow silica, inorganic materials such as clay, kaolin, talc, mica, glass powder, quartz powder, and glass balloons In addition to organic fillers (inorganic fillers), organic fillers such as styrene-type, butadiene-type, acrylic-type rubber powders, core-shell type rubber powders, silicone resin powders, silicone rubber powders, silicone composite powders, etc. organic fillers). These fillers may be used alone or in combination of two or more.

The resin composition used as the insulating material may contain an organic solvent. Organic solvents are not particularly limited, and include aromatic hydrocarbon solvents such as benzene, toluene, xylene, and trimethylbenzene; ketone solvents such as acetone, methyl ethyl ketone, and methyl ibutyl ketone; and tetrahydrofuran. Ether solvents; alcohol solvents such as isopropanol and butanol; ether alcohol solvents such as 2-methoxyethanol and 2-butoxyethanol; such as N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide An amide solvent or the like can be used in combination as desired. Incidentally, when producing a prepreg, the amount of solvent in the varnish is preferably in the range of 40% by mass to 80% by mass based on the entire resin composition. Further, the viscosity of the varnish is preferably in the range of 20 cP to 100 cP (20 mPa·s to 100 mPa·s).

The resin composition used as the insulating material may contain a flame retardant. Flame retardants include, but are not particularly limited to, bromine compounds such as decabromodiphenyl ether, tetrabromo bisphenol A, tetrabromo phthalic anhydride, and tribromophenol, triphenyl phosphate, tricyl phosphate, and cresyl phosphate. Known and customary flame retardants such as phosphorus compounds such as dildiphenyl phosphate, red phosphorus and its modified products, antimony compounds such as antimony trioxide and antimony pentoxide, and triazine compounds such as melamine, cyanuric acid, and melamine cyanurate can be used. can.

The resin composition used as an insulating material may be further added with the above-mentioned curing agents, curing accelerators, thermoplastic particles, colorants, ultraviolet opaque agents, antioxidants, reducing agents, etc. as necessary. Additives and fillers can be added.

In the present embodiment, the prepreg is made of a resin composition (varnish) such that, for example, the amount of the resin composition adhered to the base material described above is 20% by mass or more and 90% by mass or less in terms of resin content in the prepreg after drying. After impregnating or coating a base material with (containing) a base material, it can be obtained as a prepreg in a semi-cured state (B stage state) by heating and drying at a temperature of 100° C. or higher and 200° C. or lower for 1 minute to 30 minutes. As such prepreg, for example, GHPL-830NS (product name) and GHPL-830NSF (product name) manufactured by Mitsubishi Gas Chemical Co., Ltd. can be used.

The insulating film material can be composed of, for example, the resin composition of the insulating material described in connection with the prepreg, and can be obtained by processing these resin compositions into a film form.

(First metal layer)
The first metal layer 12 constitutes the support body 10A together with the core resin layer 11. The first metal layer 12 can be made of, for example, metal foil with a carrier. The metal foil with a carrier is, for example, a metal foil 12B laminated on a carrier 12A via a peeling layer (not shown) serving as a peeling means. A commercial product can be used as the metal foil with a carrier, and for example, MT18SD-H-T5 (product name) manufactured by Mitsui Mining & Mining Co., Ltd. can be used. The thickness of the first metal layer 12 is appropriately set as desired and is not particularly limited, but may be, for example, 0.5 μm or more and 100 μm or less.

The carrier 12A can be made of various metal foils, for example, but is preferably made of copper foil in terms of uniformity of thickness and corrosion resistance of the foil. The thickness of the carrier 12A is thicker than the thickness of the metal foil 12B, and can 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.

The peeling layer is for making it possible to easily peel the carrier 12A and the metal foil 12B. The material for the release layer is not particularly limited, and various known materials can be used as appropriate. For example, organic materials 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 preferable because their peelability is easily stable. 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. In addition, examples of inorganic materials include metals or alloys made of at least one of Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, etc., or oxides thereof. The thickness of the release layer can be, for example, 1 nm or more and 1 μm or less, preferably 5 nm or more and 500 nm or less.

The metal foil 12B can be made of various metal foils, for example, but is preferably made of copper foil in terms of uniformity of thickness and corrosion resistance of the foil. The thickness of the metal foil 12B is appropriately set as desired and is not particularly limited, but can be, for example, 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. .

The first metal layer 12 may have the carrier 12A on the core resin layer 11 side and the metal foil 12B on the diffusion prevention layer 13 side, or the metal foil 12B on the core resin layer 11 side and the carrier 12A on the diffusion prevention layer 13 side. It may be set to the side of Note that FIG. 1 shows a case where the carrier 12A is on the core resin layer 11 side and the metal foil 12B is 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 means (in the example shown in FIG. 1, the thickness of the metal foil 12B) is preferably 6 μm or more, and may be 10 μm or more. It is more preferable if it is 15 μm or more, and even more preferably if it is 15 μm or more. This is because, after the wiring board 20A is formed on the first metal layer 12, when the core resin layer 11 is separated and removed by the peeling means, the wiring board 20A can be reinforced and damage can be suppressed. Further, the thickness from the end face of the first metal layer 12 on the diffusion prevention layer 13 side to the peeling means is preferably 70 μm or less, more preferably 50 μm or less, and even more preferably 30 μm or less. This is because if the first metal layer 12 remaining on the diffusion prevention layer 13 side becomes too thick, it will take time to remove it by etching.

Although not shown, the first metal layer 12 can also be made of a metal foil having a peeling layer that is a peeling means. In this case, the release layer is stacked on the core resin layer 11 side. Examples of the release layer include a layer containing at least a silicon compound, and can be formed, for example, by applying a silicon compound made of a single silane compound or a combination of two or more silane compounds on a metal foil. Note that the means for applying the silicon compound is not particularly limited, and for example, known means such as coating can be used. The adhesive 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 performed using nickel, tin, zinc, chromium, molybdenum, cobalt, or an alloy thereof. The thickness of the release layer is not particularly limited, but from the viewpoint of removability and peelability, it is preferably 5 nm or more and 100 nm or less, more preferably 10 nm or more and 80 nm or less, and particularly preferably 20 nm or more and 60 nm or less. Further, as the metal foil, copper foil is preferable from the viewpoint of uniformity of thickness and corrosion resistance of the foil. Also in this case, the thickness from the end surface of the first metal layer 12 on the diffusion prevention layer 13 side to the peeling means is preferably as described above.

(diffusion prevention layer)
The diffusion prevention layer 13 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 by the peeling means, and also acts as an etching stopper on the first metal layer 12. This is to prevent the constituent elements of the first metal layer 12 and the protective plating layer 15 from diffusing into each other and corroding the protective plating layer 15 when the protective plating layer 15 is provided in the protective plating layer 15 . Preferably, the diffusion prevention layer 13 contains at least one member 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 is provided, for example, in contact with the first metal layer 12. The thickness of the diffusion prevention layer 13 can be, for example, 0.5 μm or more and 10 μm or less.

(plating resist)
The plating resist 14 is provided, for example, in contact with the diffusion prevention layer 13 and has openings corresponding to the terminal positions of the wiring board 20A formed on the first metal layer 12. Note that the terminal position of the wiring board 20A is, for example, the position of an external connection terminal when the wiring board 20A is mounted on an electronic device by soldering or the like. The plating resist 14 contains, for example, an insulating resin material, and can be composed of a dry film resist, the insulating film material or prepreg described in the core resin layer 11, or the like. For example, the plating resist 14 may be removed after forming the diffusion prevention layer 13 and the protective plating layer 15, but the wiring board 20A may be formed thereon without being removed. This is because after the support 10A is separated and removed from the support-attached wiring board 20 by the peeling means, it can function as a solder resist layer.

When the plating resist 14 is used as a solder resist layer, it is preferable that the insulating resin material has a glass transition temperature of 150° C. or higher. This is because if the glass transition temperature is lower than 150° C., bulges may occur during the processing process and the wiring board 20A may be damaged. The insulating resin material in the plating resist 14 includes materials with excellent heat resistance, such as polyimide resin, epoxy resin, cyanate resin, maleimide resin, bismaleimide triazine resin, polyamideimide resin, nylon resin that is polyamide resin, and , fluororesin. Among these, it is preferable to include at least one selected from polyimide resins, bismaleimide triazine resins, and fluororesins.

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

(protective plating layer)
The protective plating layer 15 protects the surface of the external connection terminal of the wiring board 20A. It is preferable that the protective plating layer 15 has, for example, a gold plating layer 15A made of gold and a nickel plating layer 15B made of nickel from the diffusion prevention layer 13 side. The thickness of the gold plating layer 15A can be, for example, 0.05 μm or more and 0.1 μm or less, and the thickness of the nickel plating layer 15B can be, for example, 0.5 μm or more and 10 μm or less.

<Method for manufacturing laminate>
FIG. 2 shows a method for manufacturing the laminate 10. First, for example, as shown in FIG. 2(A), a core resin layer 11 and a first metal layer 12 provided on at least one surface side of the core resin layer 11 and provided with a peeling means are provided. A support 10A is prepared (support preparation step). Specifically, for example, a metal foil with a carrier or a metal foil having a release layer is placed on at least one side of the core resin layer 11, and heated and pressurized to form the support 10A. Next, for example, as shown in FIG. 2(B), a diffusion prevention layer 13 is formed by electrolytic plating on the surface of the first metal layer 12 opposite to the core resin layer 11 (diffusion prevention layer forming step). .

Subsequently, for example, as shown in FIG. 2C, a plating resist 14 is formed on the surface of the diffusion prevention layer 13 opposite to the first metal layer 12 (plating resist forming step). Specifically, for example, after laminating a dry film resist on the diffusion prevention layer 13, the plating resist 14 is formed by printing a circuit pattern on the dry film resist and developing it. Further, for example, a metal foil with a carrier and a resin layer is placed on the diffusion prevention layer 13 so that the resin layer is on the diffusion prevention layer 13 side, heated and pressurized to peel off the carrier, and then the metal foil is A dry film resist is laminated on top, baked and developed to form a resist pattern, and then the metal foil is etched to form a mask and the resist pattern is removed. The uncovered portions are removed by laser processing or the like, and the mask is removed to form a plating resist 14.

Next, as shown in FIG. 2D, for example, on the side of the diffusion prevention layer 13 opposite to the first metal layer 12, a protective plating layer 15 is applied by electrolytic plating to a region where the plating resist 14 is not provided. (protective plating layer formation process). Specifically, for example, the gold plating layer 15A and the nickel plating layer 15B are laminated in this order by electrolytic plating.

<First manufacturing method of wiring board with support and coreless board>
The laminate 10 can be used when manufacturing the wiring board 20 with a support and the coreless board 30. 3 to 5 illustrate each step of the first manufacturing method of the wiring board 20 with a support and the coreless board 30. First, for example, the laminate 10 is formed as described above (support preparation step, diffusion prevention layer formation step, plating resist formation step, and protective plating layer formation step). Next, as shown in FIG. 3A, for example, on the opposite side of the protective plating layer 15 from the diffusion prevention layer 13, a region where the plating resist 14 is not provided is subjected to electrolytic plating, for example, electrolytic copper plating. One wiring conductor 21 is formed (first wiring conductor forming step).

Subsequently, for example, as shown in FIG. 3B, a first insulating layer 22 is formed on the first wiring conductor 21 and the plating resist 14, and a second wiring conductor 23 is formed thereon. A wiring board 20 with a support having two layers of wiring conductors is obtained (first insulating layer forming step/second wiring conductor forming step). Specifically, first, for example, the surface of the first wiring conductor 21 is subjected to a roughening treatment in order to increase its adhesion to the first insulating layer 22. The roughening treatment is not particularly limited, and any known means can be used as appropriate, including, for example, means using a copper surface roughening solution. Next, for example, a carrier-attached metal foil with a resin layer is placed on the first wiring conductor 21 and the plating resist 14 so that the resin layer is in contact with the first wiring conductor 21, and heated and pressurized to form a carrier. By peeling off, the first insulating layer 22 and the second metal layer are laminated in this order. The carrier-attached metal foil with a resin layer is, for example, a resin layer laminated on the metal foil side of the carrier-attached metal foil, with the resin layer serving as the first insulating layer 22 and the metal foil serving as the second metal layer. Become.

Next, for example, by laser processing using a carbon dioxide laser or the like, a hole is made in the second metal layer and the first insulating layer 22 to form a first non-through hole 22A that reaches the first wiring conductor 21. Form and desmear. Next, the second wiring conductor 23 is formed by a known method such as a subtractive construction method or a semi-additive construction method. In the case of the subtractive construction method, for example, first, at least one of electroless plating and electrolytic plating is applied to the surface on which the first non-through hole 22A is formed, and the first wiring is formed on the inner wall of the first non-through hole 22A. A first connection via 22B is formed to connect the conductor 21 and the second metal layer, and the thickness of the second metal layer is increased, and the surface is leveled if necessary. Next, for example, a dry film resist or the like is laminated, a negative mask is attached, a circuit pattern is printed and developed, and an etching resist is formed. Subsequently, for example, the second metal layer with increased thickness is etched using the etching resist as a mask to form the second wiring conductor 23, and the etching resist is removed.

In the case of the semi-additive construction method, for example, first, the first non-through hole 22A is formed, and then the second metal layer is completely removed by etching or the like to expose the first insulating layer 22. Next, for example, electroless plating is performed to form the first connection via 22B on the inner wall of the first non-through hole 22A, and to form an electroless plating layer on the first insulating layer 22. Subsequently, for example, a resist layer is provided by thermocompression bonding a dry film on the electroless plating layer, and exposure and development are performed to form a resist pattern and remove scum (resist residue). Next, for example, using the resist pattern as a plating resist, an electrolytic plating layer is formed on the surface of the electroless copper plating layer by electrolytic plating, and after removing the resist pattern, the exposed electroless plating layer is etched to form an electroless plating layer. A second wiring conductor 23 made of a plating layer and an electrolytic plating layer is formed.

After forming the second wiring conductor 23, the same steps as the first insulating layer forming step and the second wiring conductor forming step are repeated n times, as shown in FIG. ) layer of wiring conductors may be formed (build-up process). In addition, in FIG. 3C, the same steps as the first insulating layer forming step and the second wiring conductor forming step are repeated four times to form a wiring board 20 with a support having a build-up structure and having six layers of wiring conductors. The figure shows the case where . Specifically, for example, the (m+1)th insulating layer 24 is formed on the (m+1)th insulating

layer

22, 24 and the (m+1)

th wiring conductor

23, 25. Forming step, and forming (m+1)th non-through hole 24A reaching (m+1)

th wiring conductor

23, 25 in (m+1)th insulating layer 24, forming (m+1)th non-through hole 24A The (m+2)th wiring conductor forming step of forming the (m+2)th wiring conductor 25 by applying at least one of electrolytic plating and electroless plating to the surface thus formed is performed n times in this order to form a build-up structure. (build-up process). m and n are integers of 1 or more, provided that m≦n.

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, as shown in FIG. As shown, a solder resist layer 26 is formed thereon 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 any known means can be used as appropriate.

After forming the solder resist layer 26, for example, as shown in FIG. A protective plating layer 27 is formed (plating finishing step). Specifically, for example, a nickel plating layer 27A made of nickel and a gold plating layer 27B made of gold are laminated in this order from the side of the second wiring conductor 23 or the (n+2)th wiring conductor 25.

After forming the protective plating layer 27, for example, as shown in FIG. 5(F), the core resin layer 11 is separated and removed from the wiring board 20 with a support (core resin layer separation and removal step). The core resin layer 11 is separated and removed, for example, by peeling the first metal layer 12 using a peeling means (for example, a peeling layer or a peeling layer). Although either physical means or chemical means can be used for peeling, it is preferable to apply physical force to the peeling means to peel off by physical means. By this peeling, the core resin layer 11 and, in some cases, a part of the first metal layer 12 are peeled off. At least a portion of the peeling means for the first metal layer 12 may be peeled off together with at least the core resin layer 11, or may remain without being peeled off.

After separating and removing the core resin layer 11, for example, as shown in FIG. 5(G), the remaining first metal layer 12 and 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 is not particularly limited, but can be removed using, for example, 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 those used in the industry can be used. At that 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 serves as an etching stopper, and the remaining first metal layer 12 can be easily removed. can do. Moreover, it is possible to suppress the constituent elements of the first metal layer 12 and the protective plating layer 15 from diffusing into each other, and it is possible to form a good protective plating layer. A coreless substrate 30 is thereby obtained. Note that in this coreless substrate 30, the plating resist 14 is used as a solder resist layer.

<Second manufacturing method of wiring board with support and coreless board>
6 to 8 illustrate the steps of the second manufacturing method for the wiring board 20 with support and the coreless board 30. In the second manufacturing method, after the first wiring conductor forming step and before the first insulating layer forming step and the second wiring conductor forming step, the plating resist 14 is removed using, for example, a resist stripping solution. This method is the same as the first manufacturing method except that it includes a removal step. That is, the second manufacturing method includes, for example, a support preparation step (see FIG. 2(A)), a diffusion prevention layer forming step (see FIG. 2(B)), and a plating resist forming step (see FIG. 2(C)). , protective plating layer forming step (see FIG. 2(D)), first wiring conductor forming step (see FIG. 3(A)), plating resist removal step (see FIG. 6(A)), first insulating layer forming step Process - Second wiring conductor formation process (see Figure 6 (B)), build-up process (see Figure 6 (C)), solder resist layer formation process (see Figure 7 (D)), plating finishing process (see Figure 7 (E)), a core resin layer separation/removal step (see FIG. 8(F)), and a first metal layer/diffusion prevention layer removal step (see FIG. 8(G)). Therefore, detailed description of the same steps will be omitted with reference to the drawings. Note that in the coreless substrate 30 obtained by the second manufacturing method, the first insulating layer 22 is used as a solder resist layer.

<Third manufacturing method of wiring board with support and coreless board>
9 and 10 illustrate the steps of the third manufacturing method for the wiring board 20 with support and the coreless board 30. The third manufacturing method includes a support substrate lamination step of laminating 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. This method is the same as the first manufacturing method or the second manufacturing method except that it includes steps. Since the steps from the support preparation step to the plating finishing step are the same as those in the first manufacturing method or the second manufacturing method, detailed explanations will be omitted. Note that FIGS. 9 and 10 show the case where the plating resist 14 is used without being removed, similarly to the first manufacturing method.

In the third manufacturing method, after performing the plating finishing process, for example, as shown in FIG. (support substrate lamination process). The support substrate 28 is for reinforcing the wiring board 20A and suppressing damage when at least the core resin layer 11 is separated and removed in the subsequent core resin layer separation and removal process.

The support substrate 28 may have a thermosetting resin layer in addition to the thermoplastic resin layer, for example, or may be composed of only the thermoplastic resin layer. This is because thermoplastic resins have higher toughness and higher strength than thermosetting resins. The material of the thermoplastic resin layer is not particularly limited, and examples thereof include dry film resist. Among these, it is preferable to use a photosensitive resin layer made of a photosensitive thermoplastic resin. This is because the process of forming wiring conductors can be used. Examples of photosensitive thermoplastic resins include dry film resists used for patterning. Further, the thermoplastic resin layer may be composed of, for example, a UV peelable resin layer or a thermally peelable resin layer, and is composed of a photosensitive resin layer, a UV peelable resin layer, and a thermally peelable resin layer. It is preferable to have at least one selected from the group.

The supporting substrate 28 can be laminated by, for example, placing a film-like or sheet-like supporting substrate 28 on the solder resist layer 26 and the protective plating layer 27 and laminating them by pressure bonding. In addition, when the thermoplastic resin layer is constituted by a photosensitive resin layer, the step of laminating the photosensitive resin layer includes, for example, arranging the photosensitive resin layer on the solder resist layer 26 and the protective plating layer 27, After laminating, the method may include a step of 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 plating layer 27 is increased. When the thermoplastic resin layer is composed of a UV peelable resin layer or a thermally peelable resin layer, the step of laminating the UV peelable resin layer or the thermally peelable resin layer includes, for example, the solder resist layer 26 and the protective plating layer. The method may include a step of disposing a UV peelable resin layer or a heat peelable resin layer on the layer 27 and laminating the layer. The thickness of the supporting 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.

After the support substrate lamination step, for example, as shown in FIG. resin layer separation and removal process). After the core resin layer separation and removal step, for example, as shown in FIG. 10C, the remaining first metal layer 12 and diffusion prevention layer are removed in the same manner as in the first manufacturing method and the second manufacturing method. 13 (first metal layer/diffusion prevention layer removal step).

After the first metal layer/diffusion prevention layer removal step, for example, as shown in FIG. 10(D), the support substrate 28 is removed to obtain the coreless substrate 30 (support substrate removal step). The means for removing the support substrate 28 is not particularly limited, and can be appropriately selected depending on the material of the support substrate 28. The support substrate 28 may be removed, for example, with a chemical solution such as an aqueous sodium hydroxide solution, a laser, or a plasma treatment. In this case, the layer may be peeled off and removed by irradiation with light in the ultraviolet region, and in the case of a thermally peelable resin layer, it may be peeled off and removed by heat treatment.

As described above, according to the present embodiment, the first metal layer 12 provided with a peeling means is provided on at least one side of the core resin layer 11, and the core resin layer 11 of the first metal layer 12 is Since the diffusion prevention layer 13 is provided on the opposite surface, the diffusion prevention layer 13 is removed when the remaining first metal layer 12 is removed by etching after the core resin layer 11 is separated and removed by the peeling means. It can be used as an etching stopper. Therefore, the remaining first metal layer 12 can be easily removed. Moreover, since the constituent elements of the first metal layer 12 and the protective plating layer 15 formed thereon can be suppressed from diffusing into each other, a good protective plating layer 15 can be formed.

Furthermore, if the thickness from the end surface of the first metal layer 12 on the side of the diffusion prevention layer 13 to the peeling means is 6 μm or more, after the wiring board 20A is formed on the first metal layer 12, the peeling means When separating and removing the core resin layer 11, the wiring board 20A can be reinforced and damage can be suppressed.

[Modified example]
In the first embodiment, a diffusion prevention layer 13 is provided on the surface of the first metal layer 12 opposite to the core resin layer 11, and a plating resist is provided on the surface of the diffusion prevention layer 13 opposite to the first metal layer 12. Although the case where the plating resist 14 is provided has been described, for example, as shown in FIG. It's okay. That is, the first metal layer 12 provided on at least one side of the core resin layer 11 and provided with a peeling means, and the diffusion layer provided on the side of the first metal layer 12 opposite to the core resin layer 11. It has a prevention layer 13 and a plating resist 14, and may further have a protective plating layer 15 on the side of the diffusion prevention layer 13 opposite to the first metal layer 12. That is, the diffusion prevention layer 13 is formed in a region where the plating resist 14 is not formed in contact with the first metal layer 12, and the protective plating layer 15 is formed in the region where the plating resist is not formed. 13 is formed on the side opposite to the first metal layer 12.

This laminate 10 can be manufactured, for example, as follows. First, after preparing the support 10A in the same manner as in the first embodiment (support preparation step; see FIG. 2(A)), as shown in FIG. 12(A), the first metal layer 12 is A plating resist 14 is formed on the surface opposite to the core resin layer 11 in the same manner as in the first embodiment (plating resist forming step). Next, for example, as shown in FIG. 12(B), on the surface of the first metal layer 12 opposite to the core resin layer 11, the method of the first embodiment is applied to an area where the plating resist 14 is not formed. Similarly, the diffusion prevention layer 13 is formed (diffusion prevention layer forming step). Subsequently, as shown in FIG. 12C, for example, a protective plating layer 15 is formed on the side of the diffusion prevention layer 13 opposite to the first metal layer 12 in the same manner as in the first embodiment. plating layer formation process).

Similarly to the first embodiment, the modified laminate 10 can be used when manufacturing the wiring board 20 with a support and the coreless board 30, and the same effects as in the first embodiment can be obtained. I can do it.

The present embodiment and modified examples will be specifically explained below using Examples, but the present embodiment and modified examples are not limited to these Examples in any way.

[Example 1]
<Support preparation step> (see Figure 2(A))
A prepreg (thickness 0.100 mm, manufactured by Mitsubishi Gas Chemical Co., Ltd., product name: GHPL-830NS ST56) made by impregnating glass cloth (glass fiber) with bismaleimide triazine resin (BT resin) and making it into a B stage is used as the core resin layer 11. Then, on both sides of the core resin layer 11, as the first metal layer 12, copper foil with a carrier copper foil (copper foil; thickness 5 μm: manufactured by Mitsui Mining & Smelting Co., Ltd., product name: MT18SD-H-T5) was applied as the first metal layer 12. The carrier was placed so that the copper foil side was in contact with the core resin layer 11, and vacuum pressing was performed under the conditions of a temperature of 220±2°C, a pressure of 3±0.2MPa, and a holding time of 60 minutes. A support 10A provided with the first metal layer 12 was produced. The carrier copper foil is the carrier 12A, and the copper foil is the metal foil 12B.

<Diffusion prevention layer formation process> (see Figure 2(B))
A nickel plating layer was formed as a diffusion prevention layer 13 on the surface of the first metal layer 12 opposite to the core resin layer 11 by electrolytic plating. The thickness of the diffusion prevention layer 13 was 3 μm to 10 μm.

<Plating resist forming process> (see Figure 2(C))
A 25 μm thick dry film resist RD-1225 (Showa Denko Materials Co., Ltd. Co., Ltd., product name) was laminated. After printing a circuit pattern onto the dry film resist using a parallel exposure machine, the dry film resist was developed using a 1% aqueous sodium carbonate solution to form a plating resist 14.

<Protective plating layer formation process> (see Figure 2(D))
On the side opposite to the first metal layer 12 of the diffusion prevention layer 13, a gold plating layer 15A and a nickel plating layer 15B are laminated in this order by electrolytic plating on the area where the plating resist 14 is not provided, and a protective plating layer 15 is formed. Formed. The thickness of the gold plating layer 15A was 0.05 μm to 0.1 μm. The thickness of the nickel plating layer 15B was 3 μm to 10 μm.

<First wiring conductor formation step> (see FIG. 3(A))
On the opposite side of the protective plating layer 15 from the diffusion prevention layer 13, 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 is placed in an area where the plating resist 14 is not provided. Patterned electrolytic copper plating (electrolytic copper plating) with a thickness of 5 μm to 15 μm was applied to form the first wiring conductor 21.

<Plating resist removal process> (see Figure 6(A))
After forming the first wiring conductor 21, the plating resist 14 was peeled off using an amine resist stripper.

<First insulating layer forming step/second wiring conductor forming step> (see FIG. 6(B))
Next, the surface of the first wiring conductor 21 is roughened using copper surface roughening liquid CZ-8101 (manufactured by MEC Co., Ltd., product name) in order to increase the adhesion with the first insulating layer 22. was applied. Subsequently, on the first wiring conductor 21 and the diffusion prevention layer 13, 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: Mitsubishi Gas Chemical) Co., Ltd., product name: CRS381NSI) was placed so that the resin layer was in contact with the first wiring conductor 21, and vacuum pressed under the conditions of a pressure of 3 ± 0.2 MPa, a temperature of 220 ± 2°C, and a holding time of 60 minutes. did. Thereafter, the carrier copper foil was peeled off, and a first insulating layer 22 and a second metal layer having a thickness of 2 μm were laminated on the first wiring conductor 21.

Next, a carbon dioxide laser is irradiated from the surface of the second metal layer using a carbon dioxide laser processing machine ML605GTWIII-5200U (manufactured by Mitsubishi Electric Corporation, product name), and the second metal layer and the first insulating layer are 22 to form a first non-through hole 22A reaching the first wiring conductor 21. Next, a desmear treatment was performed using an aqueous sodium permanganate solution at a temperature of 80±5° C. and a concentration of 55±10 g/L. Subsequently, plating with a thickness of 0.4 μm to 0.8 μm is performed using electroless copper plating, and further plating is performed with a thickness of 5 μm to 20 μm using electrolytic copper plating to form the first non-through hole 22A. A first connection via 22B connecting the first wiring conductor 21 and the second metal layer was formed on the inner wall, and the thickness of the second metal layer was increased and the surface was smoothed.

Next, a dry film resist LDF515F (manufactured by Nikko Materials Co., Ltd., product name) was laminated on the second metal layer at a temperature of 110±10° C. and a pressure of 0.50±0.02 MPa. Thereafter, a negative mask was attached, a circuit pattern was printed using a parallel exposure machine, and the dry film resist was developed using a 1% sodium carbonate aqueous solution to form an etching resist. Next, the portions of the second metal layer without the etching resist were removed by etching with a cupric chloride aqueous solution, and then the dry film resist was removed using a sodium hydroxide aqueous solution to form the second wiring conductor 23.

<Build-up process> (see Figure 6(C))
After forming the second wiring conductor 23, the same steps as the first insulating layer forming step and the second wiring conductor forming step are repeated once again to form the second insulating layer 24 and the third wiring conductor 25. Thus, a wiring board 20 with a support having a build-up structure having three layers of wiring conductors was formed.

<Solder resist layer formation process> (see FIG. 7(D))
After forming the second insulating layer 24 and the third wiring conductor 25, a solder resist layer 26 was formed thereon so that the third wiring conductor 25 was partially exposed. The solder resist layer 26 was formed so that the thickness from the upper surface of the third wiring conductor 25 to the upper surface of the solder resist layer 26 was 10 μm.

<Plating finishing process> (see Figure 7 (E))
After forming the solder resist layer 26, a nickel plating layer 27A and a gold plating layer 27B were formed as a protective plating layer 27 in this order on the third wiring conductor 25 exposed from the solder resist layer 26 by electrolytic plating. The thickness of the nickel plating layer 27A was 3 μm to 5 μm. The thickness of the gold plating layer 27B was 0.05 μm to 0.1 μm. Thereby, a wiring board 20 with a support was obtained.

<Core resin layer separation/removal step, first metal layer/diffusion prevention layer removal step> (see FIGS. 8(F) and (G))
Regarding the obtained wiring board 20 with a support, physical force was applied to the boundary between the metal foil 12B of the first metal layer 12 and the carrier 12A to peel off and remove at least the core resin layer 11. Next, the remaining first metal layer 12 (specifically, metal foil 12B) and diffusion prevention layer 13 were removed using a cupric chloride aqueous solution to obtain a set of coreless substrates 30.

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 could be obtained.

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

[Example 3]
Electrolytic plating was applied to the copper foil surface of the copper foil with carrier copper foil (copper foil; thickness 5 μm: manufactured by Mitsui Mining and Mining Co., Ltd., product name: MT18SD-H-T5) used in Example 1. A copper foil with a carrier copper foil having a thickness increased to 10 μm was produced. A set of coreless substrates 30 was obtained by performing the same steps as in Example 1 except that the thickness of the metal foil 12B in the first metal layer 12 was set to 10 μm using this copper foil with carrier copper foil. That is, the thickness from the end surface of the first metal layer 12 on the diffusion prevention layer 13 side to the peeling means was 10 μm. In Example 3 as well, no corrosion of the gold plating layer 15A in the protective plating layer 15 was observed, and a good coreless substrate 30 could be obtained. Moreover, since the thickness from the end face of the first metal layer 12 on the side of the diffusion prevention layer 13 to the peeling means was set to be 6 μm or more, a high yield was obtained in the core resin layer separation and removal step.

[Comparative example 1]
A set of coreless substrates was obtained by performing the same steps as in Example 1 except that no diffusion prevention layer was formed, but corrosion of the gold plating layer in the protective plating layer was observed.

[Comparative example 2]
The same steps as in Example 1 were carried out, except that the diffusion prevention layer was not formed and the copper foil with carrier copper foil prepared in Example 3 was used to set the thickness of the metal foil in the first metal layer to 10 μm. A set of coreless substrates was obtained, but corrosion of the gold plating layer in the protective plating layer was observed.

(Characteristics evaluation)
The properties of Examples 1, 2, and 3 and Comparative Examples 1 and 2 were measured by the following method.

[Corrosion evaluation of protective plating layer]
In order to confirm the corrosion inhibiting effect of the protective plating layer 15 by the diffusion prevention layer 13, the protective plating layer 15 of the obtained coreless substrate 30 was observed. Observation was performed using the elemental analysis function of a scanning electron microscope (JSM-IT700HR, JEOL Ltd.) at a magnification of 1,000 times. The area of the protective plating layer 15 exposed from the first insulating layer 22 functioning as a solder resist layer is taken as 100%, and if the area covered with elements derived from the protective plating layer is 90% or more, there is no corrosion, and less than 90%. If so, it was determined that there was corrosion. The results obtained are shown in Table 1.

[Yield evaluation of core resin layer separation and removal process]
In the core resin layer separation/removal step, the number of damaged wiring boards was totaled with respect to the total number of wiring boards, and the yield was calculated using the following formula. The results obtained are shown in Table 1.
[Total number - Quantity found to be damaged]/Total number x 100

That is, according to this example, it was found that by providing the diffusion prevention layer 13, corrosion of the protective plating layer could be suppressed, and a good coreless substrate 30 could be obtained. Furthermore, if the thickness from the end surface of the first metal layer 12 on the diffusion prevention layer 13 side to the peeling means is 6 μm or more, damage in the core resin layer separation and removal process can be suppressed, and a high yield can be obtained. That's what I found out.

It can be used for printed wiring boards and package substrates for mounting semiconductor elements.

DESCRIPTION OF SYMBOLS 10... Laminate, 10A... Support, 11... Core resin layer, 12... First metal layer, 12A... Carrier, 12B... Metal foil, 13... Diffusion prevention layer, 14... Plating resist, 15... Protective plating layer, 15A... Gold plating layer, 15B... Nickel plating layer, 20... Wiring board with support, 20A... Wiring board, 21... First wiring conductor, 22... First insulating layer, 22A... First non-through hole, 22B...first connection via, 23...second wiring conductor, 24...(m+1)th insulating layer, 24A...(m+1)th non-through hole, 24B...(m+1)th connection via, 25...th (m+2) wiring conductor, 26... solder resist layer, 27... protective plating layer, 27A... nickel plating layer, 27B... gold plating layer, 28... support substrate, 30... coreless board

Claims

a core resin layer;
a first metal layer provided on at least one side of the core resin layer and provided with a peeling means;
a diffusion prevention layer provided on a surface of the first metal layer opposite to the core resin layer;
A laminate having.
The laminate according to claim 1, further comprising a plating resist on a surface of the diffusion prevention layer opposite to the first metal layer.
The laminate according to claim 2, further comprising a protective plating layer in a region where the plating resist is not provided on the opposite side of the first metal layer of the diffusion prevention layer.
The laminate according to claim 1, further comprising a plating resist on a surface of the first metal layer opposite to the core resin layer, together with the diffusion prevention layer.
The laminate according to claim 4, further comprising a protective plating layer on a side of the diffusion prevention layer opposite to the first metal layer.
The laminate according to claim 1, wherein the diffusion prevention layer contains at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium.
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 means is 6 μm or more.
a support preparation step of preparing a support having a core resin layer and a first metal layer provided on at least one side of the core resin layer and provided with a peeling means;
a diffusion prevention layer forming step of forming a diffusion prevention layer on the surface of the first metal layer opposite to the core resin layer;
A method for manufacturing a coreless board, including:
The method for manufacturing a coreless substrate according to claim 8, further comprising a plating resist forming step of forming a plating resist on a surface of the diffusion preventing layer opposite to the first metal layer after the diffusion preventing layer forming step. .
A protective plating layer forming step of forming a protective plating layer in a region where the plating resist is not provided on the opposite side of the first metal layer of the diffusion prevention layer after forming the plating resist. Item 9. The coreless substrate manufacturing method according to item 9.
Before the diffusion prevention layer forming step, a plating resist forming step of forming a plating resist on the 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 the diffusion prevention layer is formed in a region where a plating resist is not formed on a surface of the first metal layer opposite to the core resin layer.
The method for manufacturing a coreless substrate according to claim 11, comprising a protective plating layer forming step of forming a protective plating layer on a side of the diffusion preventing layer opposite to the first metal layer after the diffusion preventing layer forming step. .
Manufacturing the coreless substrate according to claim 8, wherein the diffusion prevention layer contains at least one selected from the group consisting of nickel, aluminum, iron, zinc, tin, lead, chromium, cobalt, silver, and palladium. Method.
The method for manufacturing a coreless substrate according to claim 8, wherein the thickness from the end face of the first metal layer on the diffusion prevention layer side to the peeling means is 6 μm or more.