JP4239650B2 - Manufacturing method of multilayer wiring board - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a multilayer wiring board. More specifically, the present invention relates to a method for manufacturing a multilayer wiring board in which interlayer connections are made by conductor posts.
[0002]
[Prior art]
2. Description of the Related Art In recent years, with the demand for higher functionality and lighter, thinner and smaller electronic devices, high-density integration and high-density mounting of electronic components are progressing. With respect to printed wiring boards, there is a demand for higher-precision processing processes such as higher wiring density and a plurality of wiring layers due to the demand for lightness, thinness, and miniaturization.
[0003]
Conventional circuit boards are generally made by patterning copper foil affixed to a glass epoxy plate made of a laminated plate impregnated with epoxy resin, and then laminating and laminating a plurality of sheets, and then using a drill. The mainstream is to use a wiring board in which a through hole is formed, a via is formed on the wall surface of the hole by copper plating, and electrical connection between layers is made. However, with the progress of miniaturization and high density of mounted components, the above wiring board has insufficient wiring density, and problems have arisen in mounting components.
[0004]
Due to such a background, a build-up multilayer wiring board has been adopted in recent years. The build-up multilayer wiring board is molded while stacking an insulating layer composed only of a resin and a conductor circuit. This build-up multilayer wiring board is thought to be suitable for ultra-high density and high speed due to its constituent materials and structure, but it ensures the adhesion between the conductor circuit and the insulating layer, and the wiring Ensuring the conduction reliability between the plates is regarded as a major problem. That is, there are two points of adhesion between the insulating layer and the conductive material formed thereon and the reliability of electrical continuity. If these adhesion and reliability of electrical continuity are not ensured, the multilayer wiring It is not desirable in terms of the reliability of the board, that is, the wiring board.
[0005]
In order to cope with this, in recent years, there is a wiring pattern on at least one surface of the insulating film, a conductive via hole is formed through the front and back surfaces of the insulating film, and the surface is electrically connected to the via hole. There is a multilayer circuit board having a structure in which a plurality of circuit boards provided with connection electrodes are laminated via insulating layers (adhesive layers) at arbitrary positions on the back surface. The circuit board used here forms a via hole from the back surface of the insulating film having a copper film formed on the surface, exposes the copper film from the via hole without penetrating, and fills the via hole by copper plating, Plating is continued until protruding from the back surface of the insulating film to form protruding electrodes in the via holes, and tin plating as a connecting metal is performed (see, for example, Patent Documents 1 and 2).
[0006]
[Patent Document 1]
JP 2000-294933 A (5th page, FIG. 1)
[Patent Document 2]
JP 2002-305378 A (page 19, FIG. 1)
[0007]
[Problems to be solved by the invention]
However, in the above-described construction method, when a plurality of circuit boards are laminated via an adhesive layer, moisture due to moisture absorption contained in the insulating layer, uncured components of the thermosetting resin contained in the insulating layer, insulation There is a problem that a decomposition component due to heating of the resin contained in the layer or a hydrolysis component of the cyanate resin diffuses into the adhesive layer when the insulating layer contains a cyanate resin. This void generation phenomenon is most likely to occur when the adhesive layer is in a fluidized state or a softened state, but in order to develop the adhesive function of the adhesive layer, the adhesive layer must be in a fluidized state or a softened state. I don't get it.
[0008]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems in a multilayer wiring board, and an object thereof is to provide a method for manufacturing a multilayer wiring board in which no void is generated in an adhesive layer.
[0009]
[Means for Solving the Problems]
That is, the present invention
1. A conductor circuit embedded in an insulating layer so as to expose one surface; a conductor post extending through the insulating layer on the conductor circuit; and a gas barrier film formed on at least the front and back exposed surfaces of the insulating layer A multilayer wiring board, wherein a plurality of wiring boards are laminated through an adhesive layer that is in a fluidized state or a softened state at the highest temperature when heat-bonding, and interlayer connection is made by the conductor posts. Production method,
2. The method for producing a multilayer wiring board according to claim 1, wherein the gas barrier film is formed of an inorganic substance.
3. The method for producing a multilayer wiring board according to claim 1 or 2, wherein a solder layer is formed at the front end of the conductor post protruding from at least the insulating layer,
4). The method for producing a multilayer wiring board according to any one of Items 1 to 3, wherein the adhesive layer is made of an adhesive having a surface cleaning function,
5. The wiring board forming a conductor circuit on a metal layer; forming a gas barrier film so as to cover the metal layer and the conductor circuit; forming an insulating layer on the gas barrier film; Items 1 to 4 obtained by forming a via hole in the insulating layer so that a part of the conductor circuit is exposed, forming a conductor post in the via hole, and removing the metal layer. A method for producing a multilayer wiring board according to any one of
Is to provide.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings, but the present invention is not limited thereto.
[0011]
FIG. 1 is a view for explaining an example of a method for manufacturing a multilayer wiring board according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view showing the structure of the resulting multilayer wiring board. FIG. 3 shows a conventional embodiment.
[0012]
First, the required number of wiring boards 110 (110a, 110b, 110c) (for three layers in the figure) and the substrate to be connected 120 are prepared, and the adhesive layer 130 (130a, 130b, 130c) is placed between them. It arrange | positions (FIG. 1 (a)). The wiring board 110 includes a conductor circuit 102 embedded in the insulating layer 103 so as to expose one surface, a conductor post 105 that penetrates through the insulating layer 103 to reach the conductor circuit 102, and protrudes from the insulating layer 103. It is composed of gas barrier films 111 and 112 formed on the front and back exposed surfaces of the insulating layer 103. The conductor circuit 102 and the conductor circuit 122 are used as wiring for transmitting signals in the plane direction of the multilayer wiring board 100. The conductor post 105 is used as a wiring for transmitting a signal in the thickness direction of the multilayer wiring board 100 by electrically and mechanically connecting the conductor circuit 102 and the conductor circuit 122. Here, the wiring board 110 is in a rigid state at room temperature and has a characteristic of maintaining the rigid state at the highest temperature when heat-bonding with the adhesive layer 130. Further, the adhesive forming the adhesive layer 130 has a characteristic of being in a fluidized state or a softened state at the highest temperature when the adhesive layer 130 is heated and bonded, and the state at normal temperature may be arbitrary.
[0013]
In addition, although the to-be-connected board | substrate 120 may be what kind of structure, in FIG. 1A, the conductor circuit 122 for connecting with the conductor post 105c of the wiring board 110c to be connected, and the conductor circuit 122 are supported. The example comprised from the base material 123 and the gas barrier film 121 which covers the exposed surface of the base material 123 is shown. The conductor circuit 122 may be embedded in the base material 123 so as to expose one surface, or may protrude from the surface of the base material 123 in contact with the base material 123 and one surface. In other words, the substrate to be connected 120 can be obtained by removing the metal layer 101 from the circuit board 110 shown in FIG. Alternatively, as shown in FIG. 2A, a substrate in which the conductor circuit 102 is formed on the metal layer 101 can be used as the connected substrate 120. In this case, since no gas is generated from the metal layer 101 and the conductor circuit 102, a gas barrier film is not particularly necessary. The material of the base material 123 may be the same material as that of the insulating layer 103 constituting the wiring board 110.
[0014]
The conductor post 105 of the wiring board 110 may have any configuration as long as it can obtain an interlayer connection. However, as shown in FIG. 1, the portion that penetrates the insulating layer 103 and the protruding tip surface are covered. It is preferable that it is made of a solder layer, or the conductor post 105 itself is made of solder or conductive paste. By doing so, at least the tip portion of the conductor post 105 and the opposing conductor circuit can be electrically and mechanically connected.
[0015]
Examples of the material of the conductor post 105 include Cu, Ni, Au, Sn, Ag, Pd, and the like. In particular, by using copper, a stable conductor post 105 with low resistance can be obtained. The material of the solder covering the tip surface may be any metal as long as it can be metal-bonded to the opposing conductor circuit, but Sn, In, or Sn, Ag, Cu, Zn, Bi, Pd, Sb, It is preferable to use solder composed of at least two of Pb, In, and Au. More preferably, it is an environmentally friendly Pb-free solder.
[0016]
Examples of the conductive paste include Cu, Ni, Au, Sn, Ag, and Pd dispersed in a resin, Sn and In, or Sn, Ag, Cu, Zn, Bi, Pd, Sb, Pb, and In. And a solder in which at least two kinds of Au are dispersed in a resin.
[0017]
As a method for forming the conductor post 105, any method may be used. Examples thereof include a method of filling a via hole formed in the insulating layer 103 with a metal by plating and a method of filling a conductive paste. When the conductor post 105 is formed by electrolytic plating, the tip shape of the conductor post 105 can be freely controlled from a flat shape to a convex shape by selecting a plating current density and an additive to the plating bath. Can do.
[0018]
As the insulating layer 103, a thermosetting resin or a thermoplastic resin can be used. Examples of the thermosetting resin include resins such as epoxy, phenol, bismaleimide, bismaleimide / triazine, triazole, cyanate, isocyanate, and benzocyclobutene. Thermoplastic resins include polyamide, polyimide, polyamideimide, polyetherimide, polyesterimide, polyetheretherketone, polyphenylene sulfide, polyethersulfone, polyquinoline, polynorbornene, polybenzoxazole, polybenzimidazole, polytetrafluoro Examples thereof include resins such as ethylene and liquid crystal polymer. These may be used singly or in combination, and inorganic fillers such as silica filler, leveling agents, coupling agents, antifoaming agents, curing catalysts and the like may be added. Alternatively, a material obtained by impregnating a resin into a reinforcing fiber such as a glass cloth or an aramid nonwoven fabric typified by a glass epoxy base material and curing or semi-curing can be used as the insulating layer 103.
[0019]
Subsequently, the wiring board 110, the adhesive layer 130, and the substrate to be connected 120 are brought into close contact with each other, and are heated and bonded together to obtain the multilayer wiring board 100 (FIG. 1B). The heating temperature may be determined in accordance with the adhesive constituting the adhesive layer 130 and the characteristics of the wiring board 110 and the connected substrate 120, but the conductor circuit facing the conductor post 105 is electrically and mechanically connected. Above the temperature at which it can be performed is preferred. Moreover, it is preferable to add a pressurization process as needed. As a method of heating and pressurizing, for example, using a vacuum press, the conductor post 105 excludes the adhesive layer 130 and heats and pressurizes until the opposing conductor circuit and the conductor post 105 are soldered. There is a method in which the adhesive layer 130 is cured and the wiring board 110 and the connected substrate 120 are bonded. In addition, when using solder, it is preferable that the maximum heating temperature is more than melting | fusing point of solder.
[0020]
In the example shown in FIG. 1, an example in which the wiring board 110 for three layers and the connected substrate 120 are bonded together with the adhesive layer 130 is shown, but the wiring board 110 for one layer and the connected substrate 120 are connected. A multilayer wiring board may be obtained by so-called sequential lamination, in which the process of adhering with the adhesive layer 130 and further adhering another wiring board 110 thereon with the adhesive layer 130 is repeated.
[0021]
In the example shown in FIG. 1, an example in which the adhesive layer 130 is used as a self-supporting adhesive film is shown. However, if it is difficult to make a self-supporting film, the wiring board 110 or the connected object is used. It may be formed directly on the surface of the substrate 120.
[0022]
In the conventional embodiment (see FIG. 3), when heating, the wiring board 310 (310a, 310b, 310c) and the substrate to be connected 320, in particular, moisture due to moisture absorption contained in the organic matter constituting them, thermosetting In some cases, an uncured component of the resin, a decomposition component due to heating of the resin, or the like diffuses into the adhesive layer 330 (330a, 330b, 330c) that is in a fluidized state or a softened state and becomes a void 350. However, in the embodiment of the present invention (see FIG. 1), the gas barrier films 111 and 112 suppress the diffusion of void generating components contained in the wiring board 110 and the connected substrate 120 into the adhesive layer 130. , No voids are generated.
[0023]
The gas barrier films 111 and 112 are preferably made of an inorganic material that has a high effect of suppressing the diffusion of void components into the adhesive layer 130. Examples of the material for the gas barrier film include inorganic substances such as silicon oxide, boron oxide, phosphorus oxide, sodium oxide, potassium oxide, lead oxide, titanium oxide, magnesium oxide, and barium oxide. The gas barrier films 111 and 112 can be formed by CVD (chemical vapor deposition) such as plasma CVD, thermal CVD, and photo CVD, or PVD (physical vapor phase) such as vacuum deposition, sputtering, and ion plating. In addition to a dry process such as a growth method), a wet process such as a spray, thermal spray method, wet-on-wet method, liquid phase precipitation method, or sol-gel method may be used.
[0024]
When it is necessary to selectively form the gas barrier films 111 and 112 on the wiring board 110 and the connected substrate 120, that is, after obtaining the wiring board and the connected substrate that do not have the gas barrier films 111 and 112, When it is necessary to form the gas barrier films 111 and 112 on the exposed front and back surfaces of the insulating layer and the exposed surface of the base material, (1) a gas barrier film is formed on the entire surface, and the unnecessary gas barrier film is removed by a laser. (2) A method in which a gas barrier film is formed on the entire surface, a photosensitive resist is formed thereon, an unnecessary portion of the gas barrier film is removed by etching or the like, and finally the photosensitive resist is removed. 3) A method of removing a photosensitive resist after forming a thin-film photosensitive resist and forming a gas barrier film on the entire surface, (4) mechanical mass Through, by forming a gas barrier film, in advance, only the necessary portions, or the like may be used a method of forming a gas barrier film.
[0025]
In the present invention, as the resin used for the adhesive layer 130, a resin having good heat resistance and insulation, such as epoxy, phenol, polyimide, polyamideimide, or the like can be used. Further, the adhesive layer is preferably an adhesive having a surface cleaning function and high insulation reliability (hereinafter referred to as a metal bonding adhesive). Examples of the surface cleaning function include a function of removing an oxide film present on the surface of the solder and the surface of the conductor circuit, and a function of reducing the oxide film. With this surface cleaning function, the wettability with the surface for connecting with the solder is sufficiently enhanced, and the metal bonding adhesive in the metal bonded portion is eliminated by the force of wet spreading of the solder, and the metal bonding adhesive is used. Residual resin hardly occurs in metal bonding, and the electrical connection reliability is high.
[0026]
As the metal bonding adhesive, an adhesive having an essential component of a resin (A) having at least one phenolic hydroxyl group and a resin (B) acting as a curing agent thereof, an epoxy resin (C), An adhesive having an imidazole ring and a compound (D) that acts as a curing agent for the epoxy resin (C) as an essential component is preferable.
[0027]
In the first preferred metal bonding adhesive, the phenolic hydroxyl group of the resin (A) having a phenolic hydroxyl group can be used to remove dirt such as oxide on the solder and metal surface or to be oxidized by the surface cleaning function. It acts as a flux for metal bonding. Furthermore, since a good cured product can be obtained by the resin (B) that acts as the curing agent, it is not necessary to wash and remove after metal bonding, and maintains electrical insulation even in high temperature and high humidity atmospheres. Enables highly reliable metal bonding.
[0028]
As the resin (A) having at least one or more phenolic hydroxyl groups used for the first preferred metal bonding adhesive in the present invention, a phenol novolak resin, an alkylphenol novolak resin, a resole resin, a cresol novolak resin, and a polyvinyl phenol resin are used. It is preferable to select from 1 or more types of these.
[0029]
Moreover, as resin (B) which acts as a hardening | curing agent, an epoxy resin, an isocyanate resin, etc. are used. Specifically, all are based on phenol-based ones such as bisphenol, phenol novolac, alkylphenol novolac, biphenol, naphthol and resorcinol, and skeletons such as aliphatic, cycloaliphatic and unsaturated aliphatic And modified epoxy compounds and isocyanate compounds.
[0030]
The resin (A) having a phenolic hydroxyl group is preferably contained in the adhesive at 20 wt% or more and 80 wt% or less from the viewpoint of bonding strength and reliability. A more preferable upper limit value is 60 wt%. On the other hand, the resin (B) acting as a curing agent is preferably contained in the adhesive at 20 wt% or more and 80 wt% or less. Moreover, you may add a coloring agent, a curing catalyst, an inorganic filler, various coupling agents, a solvent, etc. to resin used for a metal bonding adhesive.
[0031]
In the second preferred metal bonding adhesive, the imidazole ring of the compound (D) can be used to remove dirt such as oxides on the solder and the metal surface by a surface cleaning function caused by unpaired electrons of the tertiary amine, or It reduces the oxide film and acts as a flux for metal bonding. Furthermore, since the imidazole ring also acts as a curing agent for anionic polymerization of the epoxy resin (C), a good cured product can be obtained, and it is not necessary to wash and remove after solder bonding, even in a high temperature and high humidity atmosphere. Maintains electrical insulation and enables metal bonding with high bonding strength and reliability.
[0032]
Examples of the compound (D) having an imidazole ring and acting as a curing agent for the epoxy resin (C) include imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 1-benzyl-2. -Methylimidazole, 2-undecylimidazole, 2-phenyl-4-methylimidazole, bis (2-ethyl-4-methyl-imidazole), 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl- Examples include 4,5-dihydroxymethylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, or triazine addition type imidazole. Moreover, what made these epoxy adducts and what made microcapsules can also be used. These may be used alone or in combination of two or more.
[0033]
The epoxy resin (C) used in combination with the compound (D) includes phenol-based epoxy resins such as bisphenol, phenol novolac, alkylphenol novolac, biphenol, naphthol and resorcinol, and aliphatic. And epoxy compounds modified based on a skeleton such as cycloaliphatic or unsaturated aliphatic.
[0034]
As a compounding quantity of an epoxy resin (C), 30-99 wt% of the whole metal joining adhesive agent is preferable. If it is less than 30 wt%, a sufficient cured product may not be obtained. The compounding amount of the compound (D) is preferably 1 wt% or more and 10 wt% or less from the strength and reliability of metal bonding. A more preferable upper limit value is 5 wt%. Components other than the epoxy resin (C) and the compound (D) acting as a curing agent thereof include resins used for metal bonding adhesives, and thermosetting resins such as cyanate resins, acrylic resins, methacrylic resins, and maleimide resins. Or a thermoplastic resin. Moreover, you may add a coloring agent, a curing catalyst, an inorganic filler, various coupling agents, a solvent, etc. to resin used for a metal bonding adhesive.
[0035]
The method for preparing the metal bonding adhesive is, for example, a method in which a resin (A) having a solid phenolic hydroxyl group and a resin (B) acting as a solid curing agent are dissolved in a solvent, and a solid phenolic hydroxyl group is prepared. A method of preparing a resin (A) having a liquid phenolic hydroxyl group by dissolving it in a resin (B) acting as a liquid curing agent, and dissolving a resin (B) acting as a solid curing agent in a resin (A) having a liquid phenolic hydroxyl group A method in which the compound (D) having an imidazole ring and acting as a curing agent for the epoxy resin (C) is dispersed or dissolved in a solution obtained by dissolving the solid epoxy resin (C) in a solvent, And a method of dispersing or dissolving the compound (D) having an imidazole ring in the epoxy resin (C) and acting as a curing agent for the epoxy resin (C).
[0036]
Solvents used for metal bonding adhesives include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, mesitylene, xylene, hexane, isobutanol, n-butanol, 1-methoxy, 2-propanol acetate, butyl cellosolve, ethyl Cellosolve, methyl cellosolve, cellosolve acetate, ethyl lactate, ethyl acetate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diethylene glycol, benzoic acid-n-butyl, N-methylpyrrolidone, N, N-dimethylformamide, Tetrahydrofuran, γ-butyllactone, anisole and the like can be mentioned. A solvent having a boiling point of 200 ° C. or lower is preferable.
[0037]
FIG. 2 is a diagram for explaining an example of a method for manufacturing a wiring board used in the method for manufacturing a multilayer wiring board according to an embodiment of the present invention, and FIG. 2 (g) shows the structure of the obtained wiring board. It is sectional drawing.
[0038]
First, a patterned conductor circuit 102 is formed on the metal layer 101 (FIG. 2A). The material of the metal layer 101 may be any material as long as it is suitable for this manufacturing method. In particular, the metal layer 101 is resistant to the chemical solution used, and is finally etched or peeled off. It is preferably removable. Examples of the material of the metal layer 101 include copper, a copper alloy, a 42 alloy, and nickel. In particular, the copper foil, the copper plate, and the copper alloy plate are preferable for use as the metal layer 101 because not only electrolytic plated products and rolled products can be selected, but also various thicknesses can be easily obtained.
[0039]
The material of the conductor circuit 102 may be any material as long as it is suitable for this manufacturing method, and examples thereof include copper, nickel, gold, tin, silver, and palladium. In particular, by using copper as the material of the conductor circuit 102, a stable conductor circuit 102 with low resistance can be obtained. As a method for forming the conductor circuit 102, a method of forming by electroplating using the metal layer 101 as an electrode, a method of forming by electroless plating, a method of etching a conductive layer (not shown) formed on the metal layer 101, conductive And a method of printing an adhesive paste. In the case of a method using electrolytic plating or electroless plating, a conductive circuit 102 can be obtained by forming a patterned plating resist (not shown), performing electrolysis / electroless plating, and peeling the plating resist. In the case of the etching method, a conductive layer can be formed on the metal layer 101 by sputtering or plating, and the conductor circuit 102 can be obtained by a general etching process.
[0040]
Next, the gas barrier film 111 is formed on the surface of the metal layer 101 where the conductor circuit 102 is formed (FIG. 2B). The material and forming method of the gas barrier film 111 are the same as described above.
[0041]
Next, the insulating layer 103 is formed on the gas barrier film 111 (FIG. 2C). The insulating layer 103 may be formed by a method suitable for the resin to be used, such as direct application of a resin varnish by printing, curtain coating, bar coating or the like, or vacuum laminating, vacuum pressing, etc. of a dry film type resin. The method of laminating by this method is mentioned. Note that the material of the insulating layer 103 is the same as described above.
[0042]
Next, a gas barrier film 112 is formed on the exposed surface of the insulating layer 103 (FIG. 2D). The material and formation method of the gas barrier film 112 are the same as described above.
[0043]
Next, a via hole 104 is formed in the insulating layer 103 (FIG. 2E). The via hole 104 may be formed by any method as long as it is suitable for this manufacturing method, and examples thereof include laser, plasma dry etching, and chemical etching. Further, when the insulating layer 103 is made of a photosensitive resin, the via hole 104 can be formed by selectively exposing and developing the insulating layer 103. The opening by laser is advantageous because the fine via hole 104 can be easily formed regardless of whether the insulating layer 103 is photosensitive or non-photosensitive. As the laser, an excimer laser, a UV laser, a carbon dioxide gas laser, or the like can be used. Moreover, you may perform a desmear process as needed.
[0044]
Next, a conductor post 105 is formed by filling the via hole 104 with a conductor (FIG. 2F). The material and forming method of the conductor post 105 are the same as described above.
[0045]
Finally, the metal layer 101 is removed to obtain the wiring board 110 used in the method for manufacturing a multilayer wiring board of the present invention (FIG. 2 (g)). Examples of the method for removing the metal layer 101 include etching and peeling. In the case of removing by etching, a chemical solution that can etch only the metal layer 101 without etching the conductor circuit 102 may be used. When the material of the metal layer 101 and the conductor circuit 102 is the same, a barrier metal layer (not shown) that is resistant to a chemical solution for etching the metal layer 101 is formed between the metal layer 101 and the conductor circuit 102. Thus, the conductor circuit 102 can be prevented from being etched. In the case of removing by peeling, it is preferable to perform release treatment or the like on the surface of the metal layer 101 in advance so that the metal layer 101 can be peeled at the interface between the conductor circuit 102 and the insulating layer 103.
[0046]
The wiring board 110 obtained in this way has a conductor circuit 102 embedded in the insulating layer 103 so as to expose one surface, and reaches the conductor circuit 102 through the insulating layer 103 and protrudes from the insulating layer 103. And the gas barrier films 111 and 112 formed on at least the front and back exposed surfaces of the insulating layer 103, and can be used in the method for manufacturing a multilayer wiring board of the present invention.
[0047]
【The invention's effect】
According to the present invention, in a multilayer wiring board in which a plurality of wiring boards are bonded with an adhesive layer, the gas barrier film formed on the exposed front and back surfaces of the insulating layer even when the adhesive layer is in a fluidized state or a softened state when heated. Due to the effect, no void is generated in the adhesive layer. In addition, in a multilayer wiring board in which a wiring board having an insulating layer, a conductor circuit, and a conductor post is bonded with an adhesive, and the conductor post and an adjacent layer of the conductor circuit are connected, even when heated to a temperature higher than the melting point of solder, Voids are not generated in the adhesive layer due to the effect of the gas barrier film.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view for explaining an example of a method for producing a multilayer wiring board according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view for explaining an example of a method for producing a wiring board used for a multilayer wiring board according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view for explaining an example of a method for manufacturing a multilayer wiring board according to a conventional embodiment.
[Explanation of symbols]
100: multilayer wiring board
101: Metal layer
102: Conductor circuit
103: Insulating layer
104: Via hole
105, 105c: Conductor post
110, 110a, 110b, 110c: wiring board
111, 112: gas barrier film
120: Substrate to be connected
121: Gas barrier film
122: Conductor circuit
123: Base material
130a, 130b, 130c: adhesive layer
300: Multilayer wiring board
310a, 310b, 310c: wiring board
320: Substrate to be connected
330a, 330b, 330c: Adhesive layer
350: Void

Claims (5)

A conductor circuit embedded in an insulating layer so as to expose one surface; a conductor post extending through the insulating layer on the conductor circuit; and a gas barrier film formed on at least the front and back exposed surfaces of the insulating layer A multilayer wiring board, wherein a plurality of wiring boards are laminated through an adhesive layer that is in a fluidized state or a softened state at a maximum temperature when heat-bonding, and interlayer connection is made by the conductor posts. Production method. The method for manufacturing a multilayer wiring board according to claim 1, wherein the gas barrier film is formed of an inorganic substance. The method for manufacturing a multilayer wiring board according to claim 1, wherein a solder layer is formed at least on a front end of the conductor post protruding from the insulating layer. The method for manufacturing a multilayer wiring board according to claim 1, wherein the adhesive layer is made of an adhesive having a surface cleaning function. The wiring board forming a conductor circuit on the metal layer; forming a gas barrier film so as to cover the metal layer and the conductor circuit; forming an insulating layer on the gas barrier film; 5. The method according to claim 1, which is obtained by a step of forming a via hole in the insulating layer so that a part of the conductor circuit is exposed, a step of forming a conductor post in the via hole, and a step of removing the metal layer. A method for producing a multilayer wiring board according to claim 1.

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