JP3469620B2 - Multilayer printed wiring board and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer printed wiring board and a method for manufacturing the same, and particularly to a multilayer printed wiring board having a highly precise pattern, and such a multilayer printed wiring board can be manufactured at low cost. It relates to a manufacturing method.

[0002]

2. Description of the Related Art Due to the rapid development of semiconductor technology, downsizing of semiconductor packages, increase in pin count, fine pitch,
With the rapid miniaturization of electronic components, we have entered the era of so-called high-density mounting. Along with that, the number of layers and the thickness of the printed wiring board are being further reduced from one-sided wiring to double-sided wiring.

At present, a subtractive method and an additive method are mainly used for forming a copper pattern on a printed wiring board.

The subtractive method is a method in which a hole is formed in a copper-clad laminate, copper is plated on the inside and the surface of the hole, and a pattern is formed by photoetching. This subtractive method is technically high in perfection and low in cost, but it is difficult to form a fine pattern due to restrictions such as the thickness of the copper foil.

On the other hand, in the additive method, a resist is formed on a portion other than a circuit pattern forming portion on a laminated plate containing a catalyst for electroless plating, and a circuit pattern is formed on an exposed portion of the laminated plate by electroless copper plating. Is a method of forming. Although this additive method can form a fine pattern, it is difficult in terms of cost and reliability.

The multi-layer substrate is prepared by pressure-laminating a printed wiring board on one or both sides and a semi-cured prepreg obtained by impregnating glass cloth with an epoxy resin. In this case, the prepreg serves as an adhesive for each layer, and the layers are connected by forming through holes and performing electroless plating inside. Due to the progress of high-density mounting, multilayer boards are required to be thin and lightweight, and on the other hand, high wiring capacity per unit area is required. Thin boards per layer, interlayer connection, component mounting method, etc. Has been devised.

[0007]

In recent years, in order to satisfy the above requirements, a multilayer wiring board manufactured by sequentially laminating a conductor pattern layer and an insulating layer on a base material has been developed. Since this multilayer wiring board is manufactured by alternately performing photoetching of the copper plating layer and patterning of the photosensitive resin, high-definition wiring and interlayer connection at arbitrary positions are possible.

However, in any of the above methods corresponding to high-density mounting, the manufacturing process is complicated because the copper plating and the photoetching are alternately performed a plurality of times, and the serial process of stacking one layer at a time is required. Therefore, if a trouble occurs in the intermediate process, it becomes difficult to reproduce the product, which hinders the reduction of the manufacturing cost. In addition, in the conventional multilayer wiring board, a convex portion is formed in a wiring pattern forming portion that connects layers, and the more conductive pattern layers are formed and the higher the pattern density is, the higher the height of the convex portion is. The number of convex portions also increased, and a multilayer wiring board having a flat outermost surface could not be obtained. Therefore, in the conventional multilayer wiring board, there is a problem that a problem occurs when an electronic component or the like is mounted on the surface thereof, and in order to avoid this, there is a restriction in the pattern design.

The present invention has been made in view of the above circumstances, and has a multilayer printed wiring board having a high-definition pattern and a flat outermost surface, and plating and photoetching on the board. An object of the present invention is to provide a manufacturing method capable of manufacturing such a multilayer printed wiring board at low cost without including steps.

[0010]

In order to achieve such an object, a multilayer printed wiring board according to the present invention comprises a substrate, a wiring layer and a through hole layer which are alternately transferred and laminated on the substrate, and The wiring layer and the through-hole layer have a conductive portion of a predetermined pattern in the plane direction and an insulating portion located at the non-existing portion of the conductive portion, and the conductive portion of the wiring layer is
It is composed of a metal conductive material,
The conductive portion is made of a non-metal conductive material .

In the method for manufacturing a multilayer printed wiring board according to the present invention, a conductive material and an insulating material are electrodeposited on a transfer substrate,
Then, on one side of the substrate for the multilayer printed wiring board,
A conductive material and an insulating material are transferred to form a layer having a conductive portion and an insulating portion in a predetermined pattern in the plane direction, and thereafter, similarly, a predetermined transfer substrate is used to form a flat surface on the layer. By providing a layer having a conductive portion and an insulating portion of a predetermined pattern in the direction (2n + 1) layers (n is an integer of 1 or more), it is formed between the (n + 1) wiring layer and each wiring layer. And n through-hole layers are formed .
The conductive material and the insulating material for forming the through-hole layer are configured to be adhesive.

[0012]

The laminated wiring layer and the through-hole layer each have a conductive portion and an insulating portion of a predetermined pattern in the plane direction, and the wiring layer and the through-hole layer are made of a conductive material provided on the transfer substrate. Since it is formed by transferring the insulating material and the insulating material onto the substrate, plating and photo-etching steps on the substrate are unnecessary, and it is possible to flatten the multilayer wiring board and simplify the manufacturing process.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view showing an example of the multilayer printed wiring board of the present invention. In FIG. 1, a multilayer printed wiring board 1 includes a substrate 2, a first wiring layer 3 provided on the substrate 2, and a second wiring layer 3 laminated on the wiring layer 3 with a through hole layer 4 interposed therebetween. A multilayer printed wiring board having a three-layer structure including a wiring layer 5 of a layer and a wiring layer 7 of a third layer further laminated on the wiring layer 5 with a through-hole layer 6 interposed therebetween.

The multilayer printed wiring board 1 includes a wiring layer 3,
Conductive parts 3 having a predetermined pattern in the surface direction in the layers as 5 and 7.
One of the features is that it is provided with a layer having a, 5a, 7a and insulating portions 3b, 5b, 7b located at the non-existing portions of the conductive portion. Also, the through hole layer 4,
6 also has conductive portions 4a, 4a,
6a and insulating portions 4b and 6b located at the non-existing portions of the conductive portion.

Therefore, the multilayer printed wiring board 1 of the present invention is
Does not have a convex portion in the wiring pattern forming portion as seen in the conventional multilayer printed wiring board, and the flat state is always maintained even by the multilayer lamination.

The substrate 2 may be a known substrate for a multilayer printed wiring board, such as a glass epoxy substrate, a polyimide substrate, an alumina ceramic substrate, a glass epoxy / polyimide composite substrate, or the like. The thickness of the substrate 2 is preferably in the range of 5 to 1000 μm.

The thickness of the wiring layers 3, 5, 7 is preferably in the range of 1 to 50 μm, and the conductive portions 3a, 5a,
7a and insulating parts 3b, 5b, 7b have a minimum width of 5 μm.
It can be set arbitrarily up to the range.

The thickness of the through hole layers 4 and 6 is 1 to
The thickness is preferably in the range of 50 μm, and the conductive portion 4a,
The size of 6a can be arbitrarily set within the range of 5 μm or more.

In the above example, the multilayer printed wiring board 1 has a three-layer structure, but the multilayer printed wiring board of the present invention has a desired number of wiring layers by repeatedly stacking in the same stacking order. Can be

Next, the manufacturing method of the multilayer printed wiring board of the present invention will be described with reference to FIGS.

First, a manufacturing example using an electrodeposition adhesive insulating material will be described.

Photoresist is applied on a conductive substrate 21 as a transfer substrate to form a photoresist layer 22 (FIG. 2A). Then, the photoresist layer 22 is contact-exposed and developed using a predetermined photomask to expose the surface of the conductive substrate 21 with the pattern of the insulating portion (FIG. 2).
(B)).

Next, an electrodeposition adhesive insulating material is electrodeposited on the conductive substrate 21 to form an adhesive insulating film 23 (FIG. 2).
(C)). Then, the photoresist layer 22 is peeled off, and a conductive film 24 is electrodeposited on the exposed conductive substrate 21 by plating (FIG. 2D).

Then, on the substrate 2 on which the adhesive layer is formed,
The conductive substrate 21 is pressure-bonded so that the insulating film 23 and the conductive film 24 are in contact with the adhesive layer. After that, the conductive substrate 21 is peeled off and the insulating film 23 and the conductive film 24 are transferred onto the adhesive layer to form the wiring layer 3 on the substrate 2.

Next, the through hole layer 4 is formed on the wiring layer 3 transferred and formed on the substrate 2 as described above.

After a photoresist is applied on the conductive substrate 31 as a transfer substrate to form a photoresist layer 32 (FIG. 3A), the photoresist layer 32 is exposed to light and developed using a photomask. Then, the surface of the conductive substrate 31 is exposed by the pattern of the insulating portion (FIG. 3B).
Next, an electrodeposition adhesive insulating material is electrodeposited on the conductive substrate 31 to form an adhesive insulating film 33 (FIG. 3C). After that, the photoresist layer 32 is peeled off, and an adhesive conductive material is electrodeposited on the exposed conductive substrate 31 to form a conductive film 34 to be a through hole (FIG. 3D). Here, as the adhesive conductive material, carbon fine particles, gold fine particles, silver-palladium fine particles, silver fine particles, in addition to the above electrodeposition adhesive insulating material,
It is possible to use a dispersion of copper fine particles and the like.
In this way, the conductive portion forming the through-hole layer is formed of an adhesive conductive material without using a conductive metal.
Since the conductive portion (conductive film 24) of the wiring layer 3 is formed of a conductive metal and does not have adhesiveness, the wiring layer and the through-hole layer, which will be described later, can be reliably adhered to each other in the transfer process. This is because the entire area of the through hole layer needs to have adhesiveness. In addition, the through hole has a larger dimensional allowance than the conductive portion of the wiring layer, and can be formed in a columnar shape having a slightly larger diameter, and even if the electric resistance is a little large, no trouble occurs. .

Next, the conductive substrate 31 for forming the through-hole layer is placed on the wiring layer 3 of the substrate 2 by pattern alignment. At this time, the insulating film 23 and the insulating film 33, which form the wiring layer 3, and the conductive film 34 have adhesive properties and thus adhere to each other. Therefore, the conductive substrate 3
By peeling 1 away, the insulating film 33 and the conductive film 34 are transferred onto the wiring layer 3 to form the through hole layer 4.

Thereafter, similarly to the formation of the wiring layer 3 and the formation of the through hole layer 4, the wiring layer 5, the through hole layer 6 and the wiring layer 7 each consisting of an insulating film and a conductive film having a predetermined pattern are sequentially transferred. And stack.

The electrodeposition adhesive insulating material may be any substance which exhibits adhesiveness at room temperature or upon heating. For example, as the polymer to be used, anionic or cationic synthetic polymer resin having adhesiveness can be mentioned.

Specifically, as the anionic synthetic polymer resin, an acrylic resin, a polyester resin, a maleinized oil resin, a polybutadiene resin, an epoxy resin or the like may be used alone.
Alternatively, they can be used as a mixture of any combination of these resins. Further, the above-mentioned anionic synthetic polymer resin may be used in combination with a crosslinkable resin such as melamine resin, phenol resin and urethane resin.

As the cationic synthetic polymer resin,
Acrylic resin, epoxy resin, urethane resin, polybutadiene resin, polyamide resin, polyimide resin and the like can be used alone or as a mixture of any combination thereof. Further, the above-mentioned cationic synthetic polymer resin may be used in combination with a crosslinkable resin such as polyester resin and urethane resin.

If necessary, a tackifying resin such as a rosin-based resin, a terpene-based resin, or a petroleum resin-based resin may be added to impart tackiness to the polymer resin.

The above-mentioned polymer resin is used in the electrodeposition method in a state in which it is solubilized in water by being neutralized with an alkaline or acidic substance, or in a water-dispersed state. That is, the anionic synthetic polymer resin is neutralized with amines such as trimethylamine, diethylamine, dimethylethanolamine and diisopropanolamine, and inorganic alkali such as ammonia and caustic potash. Further, the cationic synthetic polymer resin is
Neutralize with acids such as acetic acid, formic acid, propionic acid, and lactic acid. The polymer resin neutralized and solubilized in water is used in a state of being diluted with water as a water dispersion type or a dissolution type.

Next, a production example using a photosensitive adhesive insulating material will be described.

A photosensitive adhesive insulating material is applied on a conductive substrate 41 as a transfer substrate to form a photosensitive adhesive insulating layer 42 (FIG. 4A). Then, the photosensitive adhesive insulating layer 42 is exposed to light and developed by using a photomask to develop the insulating film 43.
And the surface of the conductive substrate 41 is exposed by the pattern of the conductive portion (FIG. 4B).

Next, a conductive film 44 is electrodeposited on the exposed conductive substrate 41 by plating (FIG. 4C).

The wiring layer 3 can be formed by transferring the insulating film 43 and the conductive film 44 thus formed on the conductive substrate 41 onto the substrate 2 via the adhesive layer.

Next, the through hole layer 4 is formed on the wiring layer 3 transferred and formed on the substrate 2 as described above.

A photosensitive adhesive insulating material is applied on a conductive substrate 51 as a transfer substrate to form a photosensitive adhesive insulating layer 52 (FIG. 5 (A)). Then, the photosensitive adhesive insulating layer 52 is contact-exposed and developed using a photomask to develop the insulating film 53.
And the surface of the conductive substrate 51 is exposed by the pattern of the conductive portion (FIG. 5B).

Next, an adhesive conductive material is electrodeposited on the exposed conductive substrate 51 to form a conductive film 54 to be a through hole (FIG. 5C).

Then, the through-hole layer 4 can be formed by transferring the insulating film 53 and the conductive film 54 having adhesiveness onto the wiring layer 3.

Similarly, the wiring layer 5 and the through hole layer 6 are formed.
And the wiring layer 7 is formed.

The above-mentioned photosensitive adhesive insulating material is a positive type,
Either negative type may be used. In the case of the positive type, as a substance that promotes dissolution by light irradiation, such as novolak resin,
A quinonediazide-based, nitrobenzyl sulfonate-based, dihydropyridine-based, or the like may be added, and a rosin-based, terpene-based, or petroleum resin-based resin may be added as a tackifier. Further, in the case of the negative type, any photosensitive substance which exhibits at least adhesiveness after irradiation with light may be used. Examples of such photosensitive substances include acrylic resins, polyester resins, maleated oil resins, polybutadiene resins, epoxy resins, urethane resins, polyamide resins, polyimide resins dissolved in acrylic monomers, acryloyl groups and epoxies. There are acrylic resins, polyester resins, maleated oil resins, polybutadiene resins, epoxy resins, urethane resins, polyamide resins, polyimide resins, etc. having groups in the molecule, these alone or in any combination of these resins. And a resin obtained by dissolving these resins in an acrylic monomer or an epoxy monomer can be used.

In order to impart photosensitivity to the above resin,
In the case of radical polymerization resin system, cleavage type benzoisoalkyl ether, 2,2-dimethoxy-2-phenylacetophenone, α-acyloxime ester, 2-hydroxy-2-methylpropiophenone, hydrogen abstraction type benzophenone, In the case of cationic polymerization resin system such as methyl orthobenzoyl benzoate, 4,4-bisdiethylaminobenzophenone, etc. Add a photopolymerization initiator. Also, if necessary,
A tackifying resin such as a rosin-based resin, a terpene-based resin, or a petroleum resin-based resin for imparting tackiness to the above resins may be added.

Next, another production example using a photosensitive adhesive insulating material will be described.

Photoresist is applied on a transparent conductive substrate 61 as a transfer substrate to form a photoresist layer 62 (FIG. 6 (A)), and the photoresist layer 62 is closely exposed and developed using a photomask. To expose the surface of the transparent conductive substrate 61 with the pattern of the conductive portion (FIG. 6).
(B)).

Next, a conductive film 63 is electrodeposited on the exposed transparent conductive substrate 61 by plating (FIG. 6C).
After that, the photoresist 62 is peeled off, and a photosensitive adhesive insulating material is applied on the transparent conductive substrate 61 to form a photosensitive adhesive insulating layer 64 (FIG. 6D). Then, the back surface of the transparent conductive substrate is exposed and developed to form an adhesive insulating film 65 (FIG. 6E).

After that, the conductive film 63 and the insulating film 65 formed on the transparent conductive substrate 61 are transferred onto the substrate 2 in the same manner as in the above-mentioned example to form the wiring layer 3.

Next, the through-hole layer 4 is formed on the wiring layer 3 transferred and formed on the substrate 2 as described above. This through-hole layer is formed by the above-mentioned method using back exposure. Instead, it is preferable to perform the method as shown in FIGS. When this is performed by the back exposure method, the conductive film (through hole) is first formed using the adhesive conductive material, but the carbon fine particles are present in the conductive film as described above. This is because the carbon fine particles scatter the light emitted from the back surface of the transparent conductive substrate, and sharp exposure cannot be performed. However, if the standard allows a large amount, the through-hole layer may be formed by the back exposure method.

Next, a manufacturing example by the screen printing method will be described. This manufacturing example is useful in the case of a pattern that does not require relatively high accuracy.

First, an adhesive insulating material is applied through a screen printing plate M on a conductive substrate 71 as a transfer substrate (FIG. 7A) to form an adhesive insulating film 72 (FIG. 7).
(B)). Then, a conductive film 73 is electrodeposited by plating on the portion of the conductive substrate 71 where the adhesive insulating film 72 is not formed (FIG. 7C). After that, the adhesive insulating film 72 and the conductive film 73 formed on the conductive substrate 71 are transferred onto the substrate 2 to form the wiring layer 3 in the same manner as in the above example.

Next, the through hole layer 4 is formed on the wiring layer 3 transferred and formed on the substrate 2 as described above. Also in this case, similarly to the above, first, the adhesive insulating material is applied on the conductive substrate 81 as the transfer substrate through the screen printing plate M (FIG. 8A) to form the adhesive insulating film 82. (FIG. 8 (B)). Next, the adhesive insulating film 8 of the conductive substrate 81
An adhesive conductive material is electrodeposited on the portion where 2 is not formed to form the conductive film 83 (FIG. 8C). Then, the through hole layer 4 can be formed by transferring the adhesive insulating film 72 and the conductive film 73 onto the wiring layer 3.

Similarly, the wiring layer 5 and the through hole layer 6 are formed.
And the wiring layer 7 is formed.

In this case, the adhesive insulating material to be used is not particularly limited, but in general, a rubber-based or acrylic resin-based adhesive can be used, and the adhesive insulating material is characterized by a solvent type or an aqueous type (emulsion). Type), a hot-melt type, etc., but a commercially available thermosetting pressure-sensitive adhesive material can also be used if necessary.

Next, a manufacturing example in which the insulating layer is of a two-layer type will be described. This production example is particularly useful when using an insulating layer that does not have a function such as adhesiveness, or when a multilayer printed wiring board is required to have a high withstand voltage and to have sufficient insulating properties.

In this manufacturing example, first, the insulating layer 102 is formed on the conductive substrate 101 as the transfer substrate, and then the photosensitive adhesive insulating material is applied on the insulating layer 102 to form the photosensitive adhesive insulating layer 103. (FIG. 9 (A)). Next, the photosensitive adhesive insulating layer 103 is contact-exposed and developed using a predetermined photomask to form an insulating film 104, and the insulating layer 102 is exposed by the pattern of the conductive portion (FIG. 9).
(B)). After that, the exposed portion of the insulating layer 102 is etched to expose the conductive substrate 101 in the pattern of the conductive portion (FIG. 9C). Next, the conductive film 105 is electrodeposited on the exposed conductive substrate 101 by plating (FIG. 9D).

After that, in the same manner as in the above-mentioned example, a two-layer insulating film composed of the insulating layer 102 and the insulating film 105 formed on the conductive substrate 101 and the conductive film 105 are transferred onto the substrate 2 to form a wiring layer. 3 is formed.

Next, the through hole layer 4 is formed on the wiring layer 3 transferred and formed on the substrate 2 as described above. Also in this case, the conductive film is formed on the conductive substrate by the same method as shown in FIG. 9 except that the conductive film is formed by electrodeposition of the adhesive conductive material instead of forming the conductive film by plating. An insulating film having a two-layer structure can be formed. Then, the through-hole layer 4 can be formed by transferring the adhesive insulating film and the conductive film onto the wiring layer 3.

Similarly, the wiring layer 5 and the through hole layer 6 are formed.
And the wiring layer 7 is formed.

As the insulating material to be used, various insulating materials conventionally used can be cited.

The substrate in which the wiring layers 7 are laminated in each of the above-described manufacturing examples is made into a multilayer printed wiring board 1 by pressing the whole at high temperature to perform main bonding. At this time, the conditions of high temperature pressurization are preferably 150 to 250 ° C. and 10 to 50 kgf / cm ² .

In the method of manufacturing the multilayer printed wiring board 1 shown in FIG. 1, a thermosetting electrodeposition adhesive insulating material can be used. For example, in the manufacturing example described in FIGS. 2 and 3, a thermosetting electrodeposition adhesive insulating material can be used instead of the electrodeposition adhesive insulating material. Further, instead of the adhesive conductive material containing carbon fine particles etc. in the electrodeposition adhesive insulating material, a thermosetting adhesive conductive material containing carbon fine particles etc. in the thermosetting electrodeposition adhesive insulating material can be used. . As the thermosetting electrodeposition adhesive insulating material, an electrodeposition adhesive insulating material such as the above-mentioned anionic or cationic synthetic polymer resin may be used, and further, a blocked isocyanate thermopolymerizable unsaturated bond may be added to these. You may add well-known thermosetting resin, such as a compound which has. In addition, the substrate in which the wiring layer 7 is laminated by using such a thermosetting electrodeposition adhesive insulating material is subjected to main adhesion by heating and pressing at a curing temperature corresponding to the thermosetting electrodeposition adhesive insulating material used. Then, the multilayer printed wiring board 1 is obtained.

Each of the above-described manufacturing examples is characterized by self-alignment in which the formation position of one of the insulating film and the conductive film is automatically determined by the formation of the other. In addition, a release layer that does not adversely affect the conductivity may be provided in advance on the surface of the conductive substrate used.

The combination of the method of forming the wiring layer and the through hole layer described in each of the above-mentioned manufacturing examples is merely an example,
The combination can be changed as appropriate.

FIG. 10 is a schematic sectional view showing an example of the multilayer printed wiring board of the present invention provided with an anisotropic conductive film between the wiring layer and the through hole layer. In FIG. 10, a multilayer printed wiring board 111 includes a substrate 112 and a first wiring layer 114 provided on the substrate 112 via an adhesive layer 113.
An anisotropic conductive film 115, a through hole layer 116, and an anisotropic conductive film 117 on the wiring layer 114, and a second wiring layer 118 laminated on the wiring layer 114; A multilayer printed wiring board having a three-layer structure including a conductive conductive film 119, a through-hole layer 120, and a third wiring layer 122 stacked via an anisotropic conductive film 121.

In this multilayer printed wiring board 111, conductive portions 114a, 118a, 122a having a predetermined pattern are formed as wiring layers 114, 118, 122 in the in-plane direction of the layers, and insulation is located at the nonexistent portions of the conductive portions. Sexual part 114b, 1
It is characterized by having a layer having 18b and 122b. The through-hole layers 116 and 120 also have conductive portions 116a and 12 in the in-plane direction in the layers, like the wiring layers.
0a and insulating portions 16b and 120b located at the non-existing portions of the conductive portion. Furthermore, each wiring layer 114, 118, 122 and through-hole layer 116, 12
0 and the anisotropic conductive film 115, 117, 119, 12
1 is provided.

Then, this multilayer printed wiring board 111
Is different from the above-described multilayer printed wiring board 1 in which each wiring layer having adhesiveness and the through-hole layer are directly laminated, the non-adhesive wiring layer and the through-hole layer are bonded via an anisotropic conductive film. It was formed by.

As the substrate 112, a substrate known as a substrate for a multilayer printed wiring board such as a glass epoxy substrate, a polyimide substrate, an alumina ceramic substrate, a glass epoxy / polyimide composite substrate, or the like can be used. The thickness of the substrate 112 is preferably in the range of 5 to 1000 μm.

The wiring layers 114, 118, 122 have a thickness of 1
It is preferably in the range of ˜50 μm. In addition, the conductive portions 114a, 118a, 122a and the insulating portion 114
b, 118b and 122b can be arbitrarily set within a range in which the minimum width is 5 μm.

The thickness of the through-hole layers 116 and 120 is preferably in the range of 1 to 50 μm, and the size of the conductive portions 116a and 120a can be arbitrarily set in the range of 5 μm or more.

The conductive portions of the wiring layer and the through hole layer can be formed by plating a metal on the electrodes of the transfer substrate and transferring the metal.

The formation of the insulating portions of the wiring layer and the through-hole layer is carried out by electrodeposition of an electrodeposition composition containing a polymer resin on the electrodes of the transfer substrate as described later, and then transfer. Can be done by.

Examples of the polymer resin used include anionic or cationic synthetic polymer resins.

Specifically, as the anionic synthetic polymer resin, acrylic resin, polyester resin, maleated oil resin, polybutadiene resin, epoxy resin or the like may be used alone.
Alternatively, they can be used as a mixture of any combination of these resins.

Further, the above anionic synthetic polymer resin may be used in combination with a crosslinkable resin such as melamine resin, phenol resin and urethane resin.

As the cationic synthetic polymer resin,
Acrylic resins, epoxy resins, urethane resins, polybutadiene resins, polyamide resins and the like can be used alone or as a mixture in any combination. further,
The above cationic synthetic polymer resin and polyester resin,
You may use together with crosslinking resin, such as urethane resin.

The above-mentioned polymer resin is used in the electrodeposition method in a state of being solubilized in water after being neutralized with an alkaline or acidic substance. That is, the anionic synthetic polymer resin,
Neutralize with amines such as triethylamine, diethylamine, dimethylethanolamine and diisopropanolamine, and inorganic alkalis such as ammonia and caustic potash. The cationic synthetic polymer resin is neutralized with an acid such as acetic acid, formic acid, propionic acid, lactic acid. The polymer resin neutralized and solubilized in water is used in a state of being diluted with water as a water dispersion type or a dissolution type.

Anisotropic conductive film 11 used in the present invention
5, 117, 119, and 121 are films that have insulating properties in the plane direction and conductivity only in the thickness direction. Specifically, the plane direction of a planar insulating resin has the same size as the resin thickness. A large number of conductive particles are distributed so as not to contact each other. The distribution of the conductive particles may be uniform or may be a predetermined pattern. In the latter case, it is necessary to align the anisotropic conductive film with the wiring layer or the through hole layer in the manufacturing process. The thickness of such an anisotropic conductive film is preferably in the range of 10 to 50 μm.

In the above example, the multilayer printed wiring board 11 is used.
Although 1 has a three-layer structure, the multilayer printed wiring board of the present invention can be provided with a desired number of wiring layers by repeatedly laminating in the same laminating order.

Next, the manufacturing method of the multilayer printed wiring board of the present invention will be described with reference to FIGS. 11 to 13 by taking the manufacturing of the above-mentioned multilayer printed wiring board 111 as an example.

First, a transfer substrate for forming a wiring layer used for manufacturing a multilayer printed wiring board and a transfer substrate for forming a through hole layer are manufactured.

Photoresist is applied on an insulating material substrate 131 such as a polyimide substrate having a copper thin film 132 to form a photoresist layer 133 (FIG. 11A), and then a photoresist layer 133 is used using a photomask. Is exposed to light and the copper thin film 132 is etched to form an electrode pattern 134 having a predetermined shape such as a stripe shape (FIG. 11).
(B)). Further, a nickel thin film 135 is formed on the electrode pattern 134 by nickel plating to form a transfer substrate 130 for forming the first wiring layer (FIG. 11).
(C)). The nickel thin film 135 is formed to enhance the peelability of the conductive film and the insulating film described later. The thin film may be formed by using other metal such as chromium instead of nickel.

Similarly, a transfer substrate for forming the second wiring layer and a transfer substrate (not shown) for forming the third wiring layer, each having a predetermined electrode pattern, are formed.

Further, the transfer substrate 13 for forming the above wiring layer.
As in the case of the fabrication of No. 0, the first through hole layer (first layer) including the electrode pattern 144 having a predetermined through hole pattern on the insulating material substrate 141 and the nickel thin film 145 formed on the electrode pattern 144 (first layer) Forming a transfer substrate 140 for forming a through hole layer provided between the wiring layer and the second wiring layer (FIG. 11D). Similarly, a transfer substrate (not shown) for forming the second through-hole layer provided between the second wiring layer and the third wiring layer is formed.

Next, the transfer substrate 13 for forming the wiring layer is formed.
0 and a transfer substrate 140 for forming a through hole layer are used to manufacture a multilayer printed wiring board.

First, of the electrode patterns 134 of the transfer substrate 130 for forming the wiring layer, the insulating material is electrodeposited only on the electrode pattern 134b (the central electrode pattern in the illustrated example) for forming the insulating film to form the insulating film 136. Form (Fig. 12
(A)). The insulating film 136 may be hardened by heating or the like. After that, a conductive film 137 is formed on the remaining electrode pattern 134a (electrode patterns at both ends in the illustrated example) by copper plating (FIG. 12B).
The order of forming the insulating film 136 and the conductive film 137 may be the reverse of the above. In the illustrated example, the insulating film 136 and the conductive film 137 are densely formed by adhering to each other. This is because the conductive film 137 formed later is a void of the pattern of the insulating film 136 formed earlier. This is because it isotropically grows so as to fill the gap and is preferable in terms of transfer performance. Further, in order to ensure good contact with the anisotropic conductive film, the conductive film 137 is used.
Is more than the insulating film 136 depending on the thickness of the anisotropic conductive film.
It is preferably about 40 μm thick.

On the other hand, an adhesive or an adhesive is applied on a substrate (transferred substrate) 112 constituting a multilayer printed wiring board to form an adhesive layer 113 (FIG. 12C). The transfer substrate 130 is pressure-bonded onto the substrate 112 so that the insulating film 136 and the conductive film 137 are in contact with the adhesive layer 113, and then the transfer substrate 130 is peeled off to adhere the insulating film 136 and the conductive film 137. Transfer to layer 113 (FIG. 12)
(D)). By the insulating film 136 and the conductive film 137 thus transferred, the first wiring layer 11 is formed on the adhesive layer 113.
4, the conductive film 137 becomes the conductive portion 114a of the wiring layer 114, and the insulating film 136 becomes the insulating portion 114b of the wiring layer 114.

Next, the anisotropic conductive film 115 is formed on the wiring layer 114.
Place on top, pressurize at high temperature and temporarily press-bond (Fig. 12).
(E)). The conditions of high temperature pressurization can be appropriately set depending on whether the anisotropic conductive film 115 is a thermoplastic type or a thermosetting type. For example, in the case of a thermoplastic type, 130 to 140 ° C., 10 kgf / cm 2
² to 5 seconds, 80 to 100 ° C for thermosetting system, 1
It can be about 5 seconds at 0 kgf / cm ² .

Next, of the electrode pattern 144 of the transfer substrate 140 for forming the first through-hole layer, only the electrode pattern 144b other than the electrode pattern 144a corresponding to the place where the through-hole is formed is electrodeposited with an insulating material to insulate it. A film 146 is formed (FIG. 13A). The insulating film 146 may be hardened by a means such as heating. After that, a conductive film 147 is formed over the electrode pattern 144a by copper plating (FIG. 13B).

Next, the transfer substrate 140 for forming the through-hole layer is placed on the anisotropic conductive film 115 of the substrate 112 to align the patterns, and then both substrates are pressure-bonded to each other. By removing 140, the insulating film 14
6 and the conductive film 147 are transferred onto the anisotropic conductive film 115 (FIG. 13C). The insulating film 146 thus transferred
The first through hole layer 116 is formed on the anisotropic conductive film 115 by the conductive film 147 and the conductive film 147. The conductive film 147 becomes the conductive portion 116a of the through hole layer 116, and the insulating film 1 is formed.
46 serves as an insulating portion 116b of the through hole layer 116.

After that, an anisotropic conductive film 117 is placed on the through hole layer 116 and pressure-bonded at high temperature to perform temporary pressure bonding (FIG. 13D).

Similarly, the second wiring layer 118 was formed on the anisotropic conductive film 117 using the transfer substrate for forming the second wiring layer, and was temporarily pressure-bonded onto the wiring layer 118. The through-hole layer 120 is formed on the anisotropic conductive film 119 by using the transfer substrate for forming the second through-hole layer. And
Anisotropic conductive film 12 temporarily press-bonded on through-hole layer 120
The transfer substrate for forming the third wiring layer is used on
The wiring layer 122 of the layer is formed (FIG. 13E).

As described above, in the method for manufacturing a multilayer printed wiring board according to the present invention, first, the transfer substrate for the first wiring layer is used to form the first wiring layer on one surface of the substrate. After that, the transfer substrate for the wiring layer and the transfer substrate for the through-hole layer are alternately used, and 2n (n is 1 or more) is formed on the first wiring layer through the anisotropic conductive film. Is an integer,
In the above example, n = 2) layers are formed, and n layer through holes are formed between the (n + 1) layer wiring layer (3 layers in the above example) and each wiring layer via an anisotropic conductive film. A layer (two layers in the above example).

Finally, the entire substrate on which the wiring layers 122 have been laminated is pressed under high temperature to be permanently bonded to form the multilayer printed wiring board 111. Hot pressing conditions can be anisotropic conductive film is appropriately set depending on whether the thermoplastic-based or thermosetting systems, for example, in the case of thermoplastic based 150 ℃, 20 kgf / cm ²
For about 20 seconds, in the case of a thermosetting system 170-180 ° C,
It can be about 20 seconds at 20 kgf / cm ² .

In the above example, the wiring layer is a multilayer printed wiring board having three layers. However, when the number of wiring layers is four or more, the wiring layer, the anisotropic conductive film, the through hole layer, the anisotropic conductive layer are used. A multilayer printed wiring board having an arbitrary number of layers can be manufactured by further laminating repeating units each composed of a film.

In addition to the conductive parts for electrically connecting the conductive parts of the upper and lower wiring layers, the through hole layer is
A conductive portion for forming a desired wiring may be formed. FIG. 14 is a schematic cross-sectional view showing an example of a multilayer printed board having a through hole / wiring pattern in a through hole layer. In FIG. 14, the multilayer printed wiring board 151
Is the substrate 152, the first wiring layer 154 provided on the substrate 152 via the adhesive layer 153, and the wiring layer 1
This is a two-layered multilayer printed wiring board having an anisotropic conductive film 155, a through hole layer 156, and a second wiring layer 158 laminated via an anisotropic conductive film 157 on 54. . This multilayer printed wiring board 151 has, as wiring layers 154 and 158, conductive portions 154a and 158a having a predetermined pattern in the in-plane direction of the layers and insulating portions 154b and 158b located where the conductive portions do not exist. A layer having. Further, the through hole layer 156 is a layer having conductive portions 156a and 156a 'in the in-plane direction in the layer and an insulating portion 156b located at a nonexistent portion of the conductive portion. Then, the conductive portion 1 of the through hole layer 156
56a is the conductive portion 15 of the upper and lower wiring layers 154 and 158.
The conductive portion 156 of the through-hole layer 156 has the function of only the through-hole that makes the 4a and 158a conductive.
Reference numeral a'denotes a through-hole / wiring pattern layer that also acts as a wiring pattern in addition to the above-mentioned function as a through hole. As a result, it is possible to further reduce the number of layer structures that form the multilayer printed wiring board.

The multilayer printed circuit board having the through hole / wiring pattern in the through hole layer is not provided with the anisotropic conductive film as shown in FIG. 1 and the wiring layer and the through hole layer are directly laminated. It can also be applied to a multilayer printed circuit board.

Next, the present invention will be described in more detail with reference to experimental examples. (Experimental Example 1) (1) (Preparation of electrodeposition liquid for electrodeposition adhesive insulating material) 13.2 parts by weight of butyl acrylate, 1.6 parts by weight of methyl methacrylate, 0.2 parts by weight of divinylbenzene and potassium persulfate Eighty-five parts by weight of a 1% aqueous solution were mixed and polymerized at 80 ° C. for 5 hours to carry out emulsion polymerization without emulsifier to prepare a polybutyl butyl polymethyl methacrylate copolymer emulsion solution.

Next, 72 parts by weight of this emulsion solution,
2 parts by weight of an acrylic copolymer resin having a carboxyl group as an electrodeposition carrier, 0.85 parts by weight of hexamethoxymelamine, 0.35 parts by weight of trimethylamine as a neutralizing agent,
3 parts by weight of ethanol, 3 parts by weight of butyl cellosolve and 18.8 parts by weight of water were mixed and stirred to prepare an anionic electrodeposition liquid. (2) (Preparation of electrodeposition liquid for electrodeposition adhesive conductive material) 65 parts by weight of the emulsion solution prepared as described above, 1.8 parts by weight of an acrylic copolymer resin having a carboxyl group as an electrodeposition carrier, carbon powder 10 parts by weight, 0.79 parts by weight of hexamethoxymelamine, 0.31 parts by weight of trimethylamine as a neutralizing agent, 2.7 parts by weight of ethanol, 2.7 parts by weight of butyl cellosolve and 16.7 parts by weight of water are mixed and stirred to generate anions. A mold electrodeposition liquid was prepared. (3) (Preparation of Photosensitive (Negative) Adhesive Insulating Material) 60 parts by weight of 2-ethylhexyl acrylate, 39 parts by weight of vinyl acetate, and α, in 40 parts by weight of refluxing ethyl acetate.
0.5 parts by weight of α'-azobisisobutyronitrile and 0.5 parts by weight of lauryl mercaptan were added dropwise and reacted for 6 hours. Next, hydroquinone was added so as to be 500 ppm with respect to the total amount of the obtained acrylic acid ester copolymer, and heated at 140 ° C. to remove the solvent to obtain an acrylic copolymer (A).

To 75 parts by weight of this acrylic copolymer (A), 10 parts by weight of Aronix M113 manufactured by Toagosei Kagaku, 5 parts by weight of acryloyloxyethyl monosuccinate, 1,
5 parts by weight of 6-hexanediol diacrylate and 5 parts by weight of Irgacure184 manufactured by Ciba-Geigy Co., Ltd. as a photopolymerization initiator were mixed and stirred at 120 ° C. so as to be uniform to prepare a photosensitive adhesive insulating material. Viscosity is 40 cp
It was diluted with methyl ethyl ketone to give a coating solution. (4) (Preparation of Thermosetting Adhesive) To 79 parts by weight of the acrylic copolymer (A) prepared as described above, 10.5 parts by weight of Aronix M113 manufactured by Toagosei Kagaku Co., Ltd. and 5 parts by weight of acryloyloxyethyl monosuccinate. Parts, 1,6-hexanediol diacrylate (5 parts by weight), and α, α'-azobisisobutyronitrile (0.5 parts by weight) are mixed and stirred to prepare a thermosetting adhesive insulating material. Was added to obtain a coating solution having a viscosity of 60,000 cps. (Experimental example 2) (Preparation of wiring layer (corresponding to FIG. 2)) A commercially available plating photoresist (PMER P-AR9 manufactured by Tokyo Ohka Kogyo Co., Ltd.) was placed on a 0.2 mm thick stainless steel plate with a polished surface.
00) to a thickness of 20 μm and dried, and contact exposure is performed using a photomask on which a wiring pattern is formed.
It was developed, washed with water, dried, and then heat-cured to prepare an electrodeposition substrate.

The above electrodeposition substrate and the platinum electrode were opposed to each other and immersed in the electrodeposition solution prepared in Experimental Example 1 (1), the electrodeposition substrate was connected to the anode of the DC power source and the platinum electrode was connected to the cathode, and 50 V was applied.
Electrodeposition was carried out for 1 minute at a voltage of 1, and this was dried and heat-treated at 180 ° C. for 30 minutes to form a patterned electrodeposition film having a thickness of 20 μm.

Next, this substrate was immersed in a stripping solution for the above photoresist (PMER P-AR900 manufactured by Tokyo Ohka Kogyo Co., Ltd.) to strip the photoresist for plating, and then this substrate and the platinum electrode. Facing each other and immersing them in a copper pyrophosphate bath, connecting a platinum electrode to the anode of a DC power source and connecting the above electrodeposition substrate to the cathode, and conducting electricity at a current density of 10 A / dm ² for 10 minutes to form an electrodeposition film. A 20 μm-thick patterned copper-plated film was formed on the bare portion of the uncoated stainless steel substrate, and the production of the wiring layer was completed. The composition of the copper plating bath used was as follows.

[0104] (copper plating bath _{composition) · Cu 2 P 2 O 7} · 3H 2 O ... 94g / l · K 4 P 2 O 7 ... 340g / l · NH 4 OH (28%) ... 3ml / l · pH ... 8.8 Liquid temperature ... 55 ° C. (Experimental example 3) (Preparation of through-hole layer (corresponding to FIG. 3)) A 0.2 mm thick stainless steel plate having a polished surface was used, and a commercially available photoresist for plating (Tokyo Ohka PM manufactured by Kogyo Co., Ltd.
ER P-AR900) is applied to a thickness of 20 μm and dried, contact exposure is performed using a photomask on which a wiring pattern is formed, followed by development, washing with water and drying, and then heat curing to form an electrodeposition substrate. It was made.

The above electrodeposition substrate and the platinum electrode were opposed to each other and immersed in the electrodeposition solution prepared in Experimental Example 1 (1), and the electrodeposition substrate was connected to the anode of the DC power source and the platinum electrode was connected to the cathode, and 50 V was applied.
Electrodeposition was carried out for 1 minute at a voltage of 1, and this was dried and heat-treated at 180 ° C. for 30 minutes to form a patterned electrodeposition film having a thickness of 20 μm.

Next, this substrate was immersed in a stripping solution dedicated to the above-mentioned photoresist (PMER P-AR900 manufactured by Tokyo Ohka Kogyo Co., Ltd.) to strip the plating photoresist, and then this substrate and the platinum electrode. Experimental example 1 with and
It is immersed in the electrodeposition liquid prepared in (2), the electrodeposition substrate is connected to the anode of the DC power source and the platinum electrode is connected to the cathode, and electrodeposition is performed at a voltage of 30 V for 90 seconds, and this is performed at 180 ° C. for 30 minutes. And dried to form a patterned electrodeposition film having a thickness of 20 μm, and the preparation of the through hole layer was completed. (Experimental example 4) (Preparation of wiring layer (corresponding to FIG. 4)) Experimental example 1
The photosensitive adhesive insulating material prepared in (3) is applied and dried to a thickness of 10 μm, and contact exposure is performed using a photomask on which a wiring pattern is formed, and then 50 parts by weight of ethanol and 50 parts by weight of methyl ethyl ketone are used. It was developed with a mixed solvent, washed and dried to form a patterned insulating film.

Then, the stainless steel substrate having the patterned insulating film and the platinum electrode are opposed to each other and immersed in a copper pyrophosphate bath, and the platinum electrode is connected to the anode of the DC power source and the above substrate is connected to the cathode, A current density of 5 A / dm ^{2 is applied} for 10 minutes, and a thickness of 1 is applied to the bare portion of the stainless steel substrate without an insulating film.
A 0 μm-patterned copper plating film was formed, and the production of the wiring layer was completed. The composition of the copper plating bath used was the same as that used in Experimental Example 2. (Experimental Example 5) (Preparation of through-hole layer (corresponding to FIG. 5)) The photosensitive adhesive insulating material prepared in Experimental Example 1 (3) was applied on a stainless steel plate having a thickness of 0.2 mm and a thickness of 10 μm.
m and m, and contact exposure is carried out using a photomask on which a wiring pattern is formed, followed by development with a mixed solvent consisting of 50 parts by weight of ethanol and 50 parts by weight of methyl ethyl ketone, washing and drying to form a pattern. An insulating film was formed.

Next, the stainless steel substrate having the patterned insulating film and the platinum electrode were made to face each other, and Experimental example 1 (2)
Immersing in the electrodeposition solution prepared in step 1, connecting the substrate to the anode of the DC power source and the platinum electrode to the cathode, and electrodeposition for 45 seconds at a voltage of 30V, and drying and heat treating at 180 ° C for 30 minutes. A patterned electrodeposition film having a thickness of 10 μm was formed to complete the production of the through hole layer. (Experimental Example 6) (Preparation of wiring layer (corresponding to FIG. 6)) 3 m indium tin oxide (ITO) transparent conductive film is provided on the surface
Commercially available photoresist for plating (PMER P-AR900 manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied to a 20 m thick glass plate and dried to a thickness of 20 μm, and contact exposure is performed using a photomask on which a wiring pattern is formed. After doing, develop, wash and dry,
Further, heat curing was performed to produce a plating substrate.

The plating substrate and the platinum electrode are opposed to each other and immersed in a copper pyrophosphate bath, the platinum electrode is connected to the anode of the DC power source and the plating substrate is connected to the cathode, and the current density is 10 A.
Electric current was applied for 10 minutes at / dm ² to form a patterned copper plating film having a thickness of 10 μm. The composition of the copper plating bath used was the same as that used in Experimental Example 2.

Next, this substrate was immersed in a stripping solution dedicated to the above photoresist (PMER P-AR900 manufactured by Tokyo Ohka Kogyo Co., Ltd.) to strip the photoresist for plating, and then the experimental example 1 (3 ) The photosensitive adhesive insulating material prepared in 1) is applied and dried to a thickness of 10 μm, and further exposed from the back surface of the substrate (using the copper plating pattern formed in the previous step as a mask), developed, washed and dried, An adhesive insulating material was formed on the non-plated portion, and the production of the wiring layer was completed. (Experimental example 7) (Production of wiring layer (corresponding to FIG. 7)) Experimental example 1 was placed on a stainless steel plate having a thickness of 0.2 mm.
Using the thermosetting adhesive prepared in (4), screen printing (using a plate on which a wiring pattern is formed) to a thickness of 1
A 0 μm patterned insulating film was formed.

Next, the stainless steel substrate having the patterned insulating film and the platinum electrode are opposed to each other and immersed in a copper pyrophosphate bath, the platinum electrode is connected to the anode of the DC power source and the above substrate is connected to the cathode, A current density of 5 A / dm ^{2 is applied} for 10 minutes, and a thickness of 1 is applied to the bare portion of the stainless steel substrate without an insulating film.
A 0 μm-patterned copper plating film was formed, and the production of the wiring layer was completed. The composition of the copper plating bath used was the same as that used in Experimental Example 2. (Experimental Example 8) (Preparation of through-hole layer (corresponding to FIG. 8)) A screen was prepared by using the thermosetting adhesive prepared in Experimental Example 1 (4) on a stainless plate having a thickness of 0.2 mm and having a polished surface. A 10 μm thick patterned insulating film was formed by printing (using a plate on which a wiring pattern was formed).

Then, the stainless steel substrate having the patterned insulating film and the platinum electrode were made to face each other, and Experimental example 1 (2)
Immersion in the electrodeposition solution prepared in 1., the above substrate was connected to the anode of the DC power source, and the platinum electrode was connected to the cathode, and electrodeposition was performed at a voltage of 30 V for 45 seconds, and this was dried at 180 ° C. for 30 minutes. A heat treatment was performed to form a patterned electrodeposition film having a thickness of 10 μm, and the production of the through-hole layer was completed. (Experimental Example 9) Experimental Example 4, Experimental Example 5 and Experimental Example 4 described above
After repeating the above, thermocompression bonding was performed under the conditions of 180 ° C. and 20 kgf / cm ² to produce a multilayer printed wiring board having two wiring layers and one through-hole layer. In this multilayer printed wiring board, conduction between the conductive parts of each wiring layer due to through holes was confirmed. (Experimental Example 10) (1) Fabrication of Transfer Substrate for Wiring Layer A copper-clad polyimide resin substrate having a thickness of 9 μm was spin-coated on a photoresist (OF of Tokyo Ohka Co., Ltd.).
PR) was applied (coating thickness = 1 μm), and contact exposure, development and etching were performed through a photomask to form a striped copper electrode pattern having a line width of 100 μm and a pitch of 120 μm as shown in FIG.

Next, a nickel plating solution (p
H4) was prepared. Then, this nickel plating solution is stirred in a plating bath while maintaining the temperature at 50 ° C., all the copper electrodes of the polyimide substrate described above are used as cathodes, the nickel plate is used as an anode, and a current of 0.5 A / dm ² is applied between both electrodes. And a nickel plating having a thickness of 1 μm was applied on the copper electrode pattern to obtain a transfer substrate for a wiring layer.

(Composition of Nickel Plating Solution) Nickel Sulfamate ... 350 g / l Nickel Chloride ... 5 g / l Boric Acid ... 40 g / l Next, in order to electrodeposit the insulating film on the transfer substrate for the wiring layer. Then, a cationic electrodeposition liquid having the following composition was prepared.

(Composition of cationic electrodeposition liquid) -Acrylic resin (manufactured by Shinto Paint Co., Ltd.) ... 8 parts-Ethyl cellosolve ... 4 parts-Isopropyl alcohol ... 0.4 parts-Acetic acid ... 0.24 parts-Pure Water ... 87.36 parts The above cationic electrodeposition liquid was stirred in an electrodeposition bath while maintaining the temperature at 20 ° C., and every other striped copper (nickel) electrode of the above wiring substrate transfer substrate was used as a cathode. A platinum plate was used as the anode, a voltage of 20 V was applied between both electrodes for 30 seconds, and an acrylic resin film (insulating film) was electrodeposited on the nickel electrode. Further, this insulating film was heated in the atmosphere at 170 ° C. for 30 minutes to be hardened.

Then, in order to form a conductive film on the transfer substrate for the wiring layer, a copper plating solution (pH 8) having the following composition was prepared.

(Composition of Copper Plating Solution) Copper Pyrophosphate: 94 g / l Potassium Pyrophosphate: 340 g / l Ammonia Water: 3 g / l The above copper plating solution was agitated while being kept at 55 ° C. in a plating bath. Then, among the striped copper (nickel) electrodes of the wiring layer transfer substrate, every other electrode without an insulating film is used as a cathode, and a copper plate is used as an anode. A current of dm ² is applied and the thickness is 1.5 on the nickel electrode.
A copper plating layer (conductive film) of μm was formed. (2) Formation of first wiring layer On the other hand, as a substrate for a multilayer printed wiring board, a thickness of 50 μm
A substrate (Himaru, Hitachi Chemical Co., Ltd.) was prepared by coating a polyimide-based thermosetting adhesive of about 20 μm on the above polyimide substrate by spin coating. Then, this substrate and the above-mentioned transfer substrate were superposed so that the pressure-sensitive adhesive layer and the insulating film and the conductive film were in contact with each other, and 10 kgf
After pressure-bonding at / cm ² , the transfer substrate is peeled off, the conductive film and the insulating film are transferred, and the first layer wiring is provided with the conductive portion and the insulating portion on the same surface as shown in FIG. Layers were formed.

An anisotropic conductive film (Anisolm manufactured by Hitachi Chemical Co., Ltd.) was placed on the first wiring layer thus prepared and pressure-bonded under the conditions of 100 ° C. and 10 kgf / cm ^2. Temporarily bonded. (3) Fabrication of Transfer Substrate for Through Hole Layer Stripe of the conductive portion of the first wiring layer formed as described above and this stripe at 90 ° as described later.
A transfer substrate for a through hole layer was produced in the same manner as the transfer substrate for a wiring layer based on a through hole pattern (see FIG. 17) having a diameter of 50 μm located at a predetermined position among the intersections with the rotated one. That is, in the same manner as in (1) above, a through-hole electrode with a diameter of 50 μm and an insulating electrode located around the circular through-hole electrode were formed using a photomask having a through-hole pattern. A donut-shaped space having a width of 20 μm exists between the through-hole electrode and the insulating electrode. Then, in the same manner as in (1) above, nickel was plated on the through-hole electrode and the insulating electrode to obtain a transfer substrate for the through-hole layer. Then, a copper plating layer (conductive film) was formed on the through-hole electrode, and an acrylic resin film (insulating film) was formed on the insulating electrode. (4) Formation of Through Hole Layer Next, after the pattern alignment is performed on the anisotropic conductive film temporarily adhered to the first wiring layer in (2) above, the through hole layer is formed. The transfer substrate of 1 is superposed on the anisotropic conductive film so that the insulating film and the conductive film are in contact with each other, and pressure-bonded at 10 kgf / cm ² , then the transfer substrate for the through-hole layer is peeled off to remove the conductive film and the insulating film. Transferred to form a through hole layer. On this through-hole layer, an anisotropic conductive film was pressure-bonded under the same conditions and temporarily bonded. (5) Formation of Second Wiring Layer Next, the transfer substrate for forming the wiring layer used for forming the first wiring layer is rotated by 90 ° and used to pass through in (4) above. A second wiring layer was formed on the anisotropic conductive film temporarily adhered to the hole layer in the same manner as in (2) above. On this wiring layer, an anisotropic conductive film was pressure-bonded under the same conditions and temporarily bonded. (6) Main Adhesion As described above, the entire substrate in which the wiring layer and the through hole layer are laminated via the anisotropic conductive film is 180 ° C., 20 kgf /
By thermocompression bonding under the condition of cm ² , a multilayer printed wiring board having two wiring layers and one through hole layer was produced. In this multilayer printed wiring board, conduction between the conductive parts of each wiring layer due to through holes was confirmed.

[0119]

As described in detail above, according to the present invention, the conductive material and the insulating material provided on the transfer substrate are transferred onto the substrate to insulate the conductive portion having a predetermined pattern from each other in the plane direction. Since the wiring layer having the conductive portion and the through-hole layer are formed, a multilayer printed wiring board with high flatness is possible, and the conductive material and the insulating material for forming the through-hole layer have an adhesive property. Since the above-mentioned wiring layer and the through-hole layer are surely transferred and adhered to each other, the conductive portion of the through-hole layer is made of a non-metal conductive material, but the through-hole is the conductive portion of the wiring layer. It is possible to make the shape larger than that of, and it does not hinder even if the electric resistance is a little large.Furthermore, since it is a parallel series process in which each layer is manufactured in parallel and sequentially transferred, By inspection of Non-defective products can be eliminated, the production yield is improved, throughput is high, and the plating and photoetching steps are required only at the transfer substrate manufacturing stage, and the plating and photoetching steps on the substrate are not required, thus eliminating waste liquid. It is not necessary to consider the treatment, and the manufacturing process can be simplified.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a multilayer printed wiring board according to the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 3 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 4 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 5 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 6 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 7 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 8 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 9 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 10 is a schematic cross-sectional view showing another example of the multilayer printed wiring board of the present invention.

FIG. 11 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 12 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 13 is a diagram illustrating a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 14 is a schematic cross-sectional view showing another example of the multilayer printed wiring board according to the present invention.

FIG. 15 is a diagram showing an electrode pattern of a transfer substrate for forming a wiring layer.

16 is a diagram showing a wiring layer formed using the transfer substrate shown in FIG.

FIG. 17 is a diagram showing a through hole pattern.

[Explanation of symbols]

1, 111 ... Multilayer printed wiring board 2, 112 ... Substrate 3, 5, 7, 114, 118, 122 ... Wiring layers 3a, 5a, 7a, 114a, 118a, 122a ... Conductive portions 3b, 5b, 7b, 114b, 118b, 122b ... Insulating portions 4, 6, 116, 120 ... Through hole layers 4a, 6a, 116a, 120a ... Conductive portions 4b, 6b, 116b, 120b ... Insulating portions 115, 117, 119, 121 ... Anisotropic Conductive film

Claims (6)

(57) [Claims] 1. A substrate, a wiring layer and a through-hole layer which are alternately transferred and laminated on the substrate, wherein the wiring layer and the through-hole layer have a conductive portion of a predetermined pattern and a non-conductive portion in a plane direction. And a conductive portion of the wiring layer is made of a metal conductive material, and a conductive portion of the through hole layer is made of a non-metal conductive material. Characteristic multilayer printed wiring board. 2. The multilayer printed wiring board according to claim 1, further comprising an anisotropic conductive film between the wiring layer and the through hole layer. 3. The conductive portion is 5 more than the insulating portion.
The multilayer printed wiring board according to claim 2, wherein the multilayer printed wiring board has a thickness of about 40 μm. 4. A conductive material and an insulating material are electrodeposited on a transfer substrate, and then the conductive material and the insulating material are transferred to one surface of a substrate for a multilayer printed wiring board, so that the conductive material and the insulating material are predetermined in a plane direction. A layer having a conductive portion and an insulating portion of the pattern is formed, and thereafter, similarly, using a predetermined transfer substrate, the conductive portion and the insulating portion having a predetermined pattern are provided in a plane direction on the layer. (2n + 1) layers (n is an integer of 1 or more) are provided to form (n + 1) wiring layers and n through-hole layers formed between the wiring layers. The method for manufacturing a multilayer printed wiring board, wherein the conductive material and the insulating material for forming the through hole layer have adhesiveness. 5. The method for manufacturing a multilayer printed wiring board according to claim 4, wherein the insulating material for forming the wiring layer has an adhesive property. 6. The wiring layer and the through hole layer are laminated with an anisotropic conductive film interposed therebetween.
Alternatively, the method for manufacturing a multilayer printed wiring board according to claim 5.