JP3347980B2 - Circuit 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 circuit board and a method of manufacturing the same, and more particularly to a low-cost circuit board having a structure in which wiring pattern layers are connected by a simple conductor wiring portion, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A circuit board of a double-sided wiring type and a circuit board of a multilayer wiring type are widely used in practical use in terms of higher density, compactness, and higher functionality of wiring circuits.
And this type of circuit board is generally made of a laminated board made by laminating copper foil on both sides of an insulator layer,
It is manufactured through the following steps.

That is, through holes are drilled one by one at predetermined positions (predetermined positions) of the copper foil-clad laminate using, for example, an NC drilling machine, and the inner wall surfaces of the drilled holes are plated by a plating method. Alternatively, it is made conductive by printing and embedding a conductive paste to electrically connect the copper foils on both surfaces.
Thereafter, the copper foil on both sides is subjected to, for example, photoetching treatment and wiring patterning to obtain a double-sided circuit board.

In the case of a multilayer circuit board, (a) a glass-resin prepreg layer is interposed between the double-sided circuit boards;
It is manufactured by laminating a copper foil via a resin-based prepreg layer and laminating and integrating this. In the case of a manufacturing method in which a copper foil is laminated, patterning of the copper foil is required.
Further, in the manufacturing process of this multilayer circuit board, the connection between the wiring patterns is via hole connection for embedding a conductor at a predetermined position of a glass-resin prepreg layer to be interposed,
Alternatively, after the multi-layering, the through hole is formed by the drilling, and the inner wall surface of the hole is made conductive by a plating method or a conductive paste.

[0005]

However, the circuit board is relatively expensive due to the complexity of the process and the like.
In addition, there is a problem that the connection operation between the wiring pattern layers in the manufacturing process is complicated, and the productivity and the like are poor. In other words, when making electrical connections between double-sided copper foils, drilling holes through the NC drilling machine one by one requires a lot of time to drill through holes, resulting in a high productivity. Is low. In particular, in a printed wiring board that requires high-density wiring or fine wiring, the number of holes to be drilled is increasing along with the minute diameter of the hole, and the means for drilling the through hole is economical and technical. It is a serious problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a circuit board capable of high-density wiring and having a simple manufacturing process, which can be obtained at low cost, and a method of manufacturing the same.

[0007]

[SUMMARY OF THE INVENTION] The invention of claim 1, the electrically
At least by penetrating the conductive protrusion in the thickness direction
Projection where the electrically connected surface is selectively projected on one surface
A first portion, the surface of the protrusion being covered with a metal layer.
A circuit board, a second circuit board having an electrically connected surface facing the protruding connected surface of the first circuit board, and a second circuit board interposed between the joined surfaces of the two circuit boards, And an anisotropic conductive adhesive layer for electrically connecting the two connected surfaces and electrically and mechanically joining the non-electrical joining surfaces.

According to a second aspect of the present invention, in the circuit board according to the first aspect, the electrically connected surface of the first circuit board is a female.
Formed by a stick layer or conductive resin
It is characterized by being.

According to a third aspect of the present invention, there is provided the first conductive foil
Forming a hardly deformable and substantially conical conductive bump on the surface
And the tip of the conductive bump on the conductive bump forming surface.
A step of laminating and arranging insulating sheets through which parts can be inserted;
Laminating and placing a second conductor foil on the insulating sheet
Outside of at least one of the two conductor foils in the laminated arrangement
And press-molded with a flexible plate interposed, and the flexible plate side
The conductor foil in the area in contact with the conductive bump is deformed and protruded.
Forming a conductor-clad substrate coated with the conductor foil;
Patterning the conductive foil of the stretched substrate.
It is characterized by doing.

[0010] According to a fourth aspect of the present invention, the conductive protrusion is formed in the thickness direction.
Through at least one surface
The connection surface includes a protrusion that is selectively protruded.
Of manufacturing a core substrate whose surface is covered with a metal layer
And an anisotropic conductive adhesive on the connected surface side of the core substrate.
Laminating and arranging agent layers, and the anisotropic conductive adhesive
On the layer, an electrical connection corresponding to the electrically connected surface of the core substrate
For positioning and positioning a circuit board with a protruding connection surface
And pressurizing the positioned and arranged laminate to form
Selectable anisotropic conductive adhesive layer area corresponding to between connection surfaces
And a process of joining and integrating
A method for manufacturing a circuit board.

[0011] According to a fifth aspect of the present invention, the conductive projection is formed in the thickness direction.
Through at least one surface
The connection surface includes a protrusion that is selectively protruded.
Manufacture a first circuit board whose surface is covered with a metal layer;
Anisotropically conductive on the connected surface side of the core substrate.
Laminating and arranging a conductive adhesive layer;
Corresponds to the electrically connected surface of the core substrate on the adhesive layer
Position and arrange a circuit board having an electrically connected surface
And pressing the laminated body that has been positioned and arranged.
Select the anisotropic conductive adhesive layer area between the connected surfaces
Process to make it electrically conductive and join and integrate
A method for manufacturing a circuit board.

[0012] The invention of claim 6 is the invention according to claim 4 or 5.
The method for manufacturing a circuit board according to claim 1, wherein the core substrate is manufactured.
The first conductor foil is hardly deformable and
Forming a substantially conical conductive bump; and
The tip of the conductive bump can be inserted through the bump forming surface.
Stacking and arranging an edge sheet;
Laminating and arranging a second conductor foil on the substrate;
A flexible plate is inserted outside at least one of the conductor foils
And press-molding, and the flexible plate side
Conductor foil covering by deforming and projecting the conductor foil in the contact area
Forming a substrate, and a conductor of the conductor foil-clad substrate
Patterning a foil.
I do.

In the above invention, the insulator of the circuit board may be, for example, epoxy resin, polyvinyl butyral resin, phenol resin, nitrile rubber, polyimide resin, phenoxy resin, xylene resin, acrylic resin, vinyl acetate resin, bismaleimide triazine resin. , Polyamide resin, polyamideimide resin, polysulfone resin,
A liquid crystal polymer, a polyetheretherketone resin, a polyetherimide resin, a polycarbonate resin, a hot melt adhesive, or a mixture of two or more thereof, or a mixture of the resin and a glass cloth, a glass mat, a synthetic fiber, a cloth, or the like. Are combined.

In the above invention, anisotropic conductive bonding is provided between the opposing joint surfaces of the circuit board to secure the required electrical connection while mechanically joining the circuit boards together. When the conductive particles dispersed and contained are pressurized and pressed, the conductive particles join and come into contact with each other to exhibit electrical conductivity. For example, a product name such as Anisorm (trade name, Hitachi Chemical Co., Ltd.) It is commercially available at

In the above invention, the conductive foil may be:
Copper foil, aluminum foil, nickel foil, gold foil, silver foil and the like can be mentioned, but copper foil is generally preferable. Further, if necessary, the conductive foil conductor is caused to protrude (protrude) and deform by pressing, and the hardly deformable conductive bump forming the connection conductor portion is formed by, for example, applying a hardening type paste through a required mask. It is manufactured by printing, drying and curing to provide projections (projections) of a desired height, or by growing projections (projections) of a desired height by selective plating. The shape (for example, a conical shape or a cylindrical shape) and the height of the projection are appropriately selected and set according to the thickness of the insulating sheet to be inserted and the fineness of the wiring pattern. Examples of the insulating sheet through which the conductive bumps are inserted include resin sheets exemplified as the insulator.

Further, the protruding connection surface (convex portion) of the first circuit board may be formed by, for example, forming a conductive layer by plating, or by using a conductive paste.

In the invention of the manufacturing method, an insulating sheet and a conductor foil through which the tip of the conductive bump can be inserted are sequentially laminated on the conductive bump forming surface of the conductor foil. It is necessary to insert a flexible plate on at least one of the outsides and press-mold it. In other words, in the press molding stage, the flexibility of the conductive foil is increased so that the conductive foil region corresponding to the pressed surface can be selectively protruded and deformed when the conductive bump is hardly deformable. To secure,
It is necessary to insert a flexible plate on the side to be deformed. If a flexible plate is interposed, there is no problem even if a backing plate such as a stainless steel plate is arranged outside and press-molded.

According to the first to third aspects of the present invention, the first
In the circuit board and the second circuit board, at least one of the electrically connected surfaces of the surfaces facing each other is selectively protruded, and the pressure between the corresponding connected surfaces is preferentially pressurized and crimped. The configuration is adopted. Therefore, the anisotropic conductive adhesive layer interposed between the joint surfaces of the two circuit boards exhibits conductivity in the preferential pressure / pressure bonding region, and connects the opposing electrically connected surfaces. Electrically join.

On the other hand, in a region other than the preferential pressure / compression bonding region, it contributes to joining and integration of both circuit boards while maintaining non-conductivity (insulation). In other words, by selectively making the conductive surfaces electrically connected to each other, the opposing connected surfaces are reliably electrically connected to each other, and these electric connections are insulated and separated from each other, so that mechanical joining and integration can be easily achieved.

According to the fourth aspect of the present invention, a circuit board suitable for the configuration of the circuit board, in other words, at least one of the electrically connected surfaces selectively protrudes and the anisotropic conductive material inserted into the bonded surface. There is provided a circuit board capable of selectively and preferentially making an adhesive layer conductive in a pressure / compression bonding region.

According to the fifth and sixth aspects of the present invention, a highly reliable circuit board of a high-density wiring type or a high-density mounting type is obtained with a high yield while simplifying the steps of via connection and through-hole connection. Can be provided at low cost.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described below with reference to FIGS. 1, 2 (a) and 2 (b), FIGS. 3, 4 and 5. FIG.

FIG. 1 is a cross-sectional view showing a main part of a circuit board according to the first embodiment. In FIG. 1, reference numeral 1 denotes a first circuit board from which an electrically connected surface 1a is selectively projected.
Is a second circuit board having an electrically connected surface 2a facing the connected surface 1a of the first circuit board 1. here,
Both circuit boards 1 and 2 are each formed using a double-sided copper foil-clad board made of glass-epoxy resin as an insulator. The connection surface 1a of the first circuit board 1 is
The conductive bump (formed of a conductive resin composition containing silver powder as a conductive agent) 1c penetrating the insulator layer 1b is formed of a copper foil portion that is deformed and protruded by a selective pressing action. That is, after the copper foil is deformed and protruded, the copper foil is patterned together with other wiring patterns 1d and the like.
2b is a wiring pattern of the second circuit board 2.

Reference numeral 3 is interposed between the surfaces to be joined of the circuit boards 1 and 2 to selectively electrically connect (make conductive) 3a between the surfaces to be connected 1a and 2a. In addition, it is an anisotropic conductive adhesive layer for electrically and mechanically joining the non-electrical joining surfaces 3b. Next, an embodiment will be described schematically with reference to FIGS. 2A and 2B, and an example of manufacturing a circuit board having the above configuration will be described.

Preparation of First Circuit Board First, a paste made of silver powder and a phenol resin is selectively printed on one principal surface by a silk screen method, dried and cured, and then dried and cured.
Conical bump 1c with a diameter of 0.3mm and a height of 200μm ± 20μm
An 18 μm-thick electrolytic copper foil 4a formed with is prepared. In addition, 18μm thick electrolytic copper foil 4b, glass / epoxy resin prepreg sheet 1b about 0.1mm thick, and 2mm thick
The silicone rubber plates 5a and 5b of the order are prepared respectively.

Next, the electrolytic copper foils 4a, 4b, the glass-epoxy resin prepreg sheet 1b, and the silicone rubber plates 5a, 5b are laminated and laminated as shown in FIG.
Deploy. Then, outside the silicone rubber plates 5a and 5b,
A stainless steel plate (not shown) with a thickness of about 2 mm is placed and set in a press, and press molding is performed by applying a resin temperature of 160 ° C and a pressure of 4 kPa for 1 hour. By this press molding, as shown in cross section in FIG. 2 (b), the tip of the conical-shaped bump 1c penetrates the prepreg sheet 1b and connects to the electrolytic copper foils 4a and 4b in the opposing regions. Copper-clad laminate 6 whose area is selectively deformed and projected
It was created.

After cooling, the electrolytic copper foil 4 of the copper-clad laminate 6
On the surfaces a and 4b, an etching resist (product name, UV etching resist AS-400 made by Taiyo Ink KK) is printed in a pattern by a screen printing method, and is exposed and developed to provide an etching resist layer. Next, using a cupric chloride bath, the exposed copper foil is removed by etching, and the etching resist layer is removed to form the first circuit board 1.

Preparation of Second Circuit Board First, a double-sided copper-foiled glass / epoxy resin-based laminate was prepared as a copper-clad laminate, and an etching resist (product Name, UV etching resist AS-400 (manufactured by Taiyo Ink KK) is printed in a pattern by screen printing, exposed and developed to provide an etching resist layer. Then, the exposed copper foil is removed by etching using a cupric chloride bath, the etching resist layer is removed, and the second circuit board 2 having an electrically connected portion 2a on one main surface is removed. It was created.

Manufacturing of Circuit Board Next, the first circuit board 1, the second circuit board 2, and the anisotropic conductive adhesive sheet are prepared.
The electrically connected portion 1a, which is formed into a projection of the first circuit board 1, is positioned and arranged with respect to the electrically connected portion 2a.
Placing plates are placed on both main surfaces of the laminate and set in a pressing device. The circuit boards are joined by applying a heating temperature of 160 ° C. and a resin pressure of 4 kPa for 1 hour to join the circuit boards 1 and 2. Manufactured.

In the above press working, both circuit boards 1
Between the two connected surfaces 1a, 2a, the connected surface 1a protrudes more than the other wiring pattern 1d not involved in the connection and is close to the opposing connected surface 2a. Therefore, both circuit boards 1
2, the anisotropic conductive adhesive layer 3 interposed between the joining surfaces
A region (part) in which the connection surfaces 1a and 2a are selectively strongly pressed and easily made conductive to form an electrical connection while the bonding surfaces of the circuit boards 1 and 2 are separated. In other words, in a region (portion) where the electrical connection is not required, the circuit board exhibits the required electrical insulation and contributes to the mechanical joining, so that a highly reliable circuit board can be obtained.

In the circuit board having the above structure, the connection resistance of the connection surfaces 1a and 2a between the first circuit board 1 and the second circuit board 2 is 10 mΩ on average, and the reliability of this connection is evaluated. In order to do this, a hot oil test was performed (a cycle of immersion in oil at 260 ° C for 10 seconds,
No failure was observed even after 100 cycles (as one cycle), and the connection reliability between the conductive (wiring) patterns was equal to or higher than that obtained by the conventional copper plating through-hole method.

Next, referring to FIG. 3 and FIG.
The configuration of the circuit board according to the example will be described.

First, a paste composed of silver powder and a phenol resin is selectively printed on one principal surface by a silk screen method, dried and cured, and dried on a bottom surface.
Conical bump 1c with a diameter of 0.3mm and a height of 200μm ± 20μm
An 18 μm-thick electrolytic copper foil 4a formed with is prepared. In addition, 18μm thick electrolytic copper foil 4b, glass 0.1mm thick
An epoxy resin-based prepreg sheet 1b and a silicone rubber plate 5a having a thickness of about 2 mm are prepared.

Next, the electrolytic copper foils 4a and 4b, the glass-epoxy resin prepreg sheet 1b, and the silicone rubber plate 5a are laminated and arranged in a manner similar to FIG. 2A (the arrangement of the silicone rubber plate 5b). Is omitted). After that, a stainless steel plate with a thickness of about 2 mm is placed outside the silicone rubber plate 5a and the electrolytic copper foil 4b and set in a pressing device. The resin is pressed at a heating temperature of 160 ° C and a resin pressure of 4kPa for 1 hour. Mold.

By this press molding, the conical bump 1c
A copper-clad laminate is prepared in which the leading end portion penetrates the prepreg sheet 1b and is connected to the electrolytic copper foils 4a and 4b in opposing regions. In this case, since the tip of the conical-shaped bump 1c penetrating the prepreg sheet 1b is restrained from entering by a stainless steel plate (contact plate), the deformation and protrusion of the electrolytic copper foil 4b, that is, the selective formation of the electrolytic copper foil 4b The copper clad laminate has a flat electrolytic copper foil 4b on one main surface and a protruding electrolytic copper foil 4a on the other main surface.

After cooling, the electrolytic copper foils 4a,
On the 4b surface, an etching resist (product name, UV etching resist AS-400 made by Taiyo Ink KK) is printed in a pattern by screen printing, and is exposed and developed to provide an etching resist layer. Then, using a cupric chloride bath,
The exposed copper foil is removed by etching, the etching resist layer is removed, and the circuit board 7 (corresponding to the first and second circuit boards) whose main configuration is shown in cross section in FIG.
7a, 7b, 7c).

Next, the first and second circuit boards 7a, 7b,
7c and an anisotropic conductive adhesive sheet are prepared, and the electrically connected parts 7b 'and 7c' of each of the circuit boards 7b and 7c are formed into projecting electrical connected parts 7a "and 7b". , 7c ". Arrange the backing plates on both main surfaces of the laminate, set it on the press, and operate it for 1 hour at a heating temperature of 160 ° C and a resin pressure of 4kPa. , 7b, and 7c were joined to produce a circuit board whose main configuration is shown in cross section in FIG.

In the press working, the circuit boards 7a, 7
b, 7c, between connected surfaces 7a "and 7b ', 7b" and 7c', 7c ", 7
The portion between b ′ protrudes from other wiring patterns not involved in the connection, and the opposing connected surfaces are close to each other. Therefore, the anisotropic conductive adhesive layer 3 interposed between the bonding surfaces of the circuit boards 7a, 7b, 7c selectively connects the connection surfaces 7a ″ -7.
b ′, 7b ″ −7c ′ and 7c ″ −7b ′ are strongly pressed,
A region (part) where the bonding surfaces of the circuit boards 7a, 7b, 7c are separated while the electrical connection is easily formed by conducting, that is, a region (part) where the electrical connection is unnecessary.
In this case, not only the required electrical insulation properties are exhibited, but also mechanical bonding is achieved, and a highly reliable circuit board can be obtained.

In the circuit board having the above configuration, the connection resistance of the connection surfaces 1a and 2a between the first circuit board 1 and the second circuit board 2 is 10 mΩ on average, and the reliability of this connection is evaluated. In order to do this, a hot oil test was performed (a cycle of immersion in oil at 260 ° C for 10 seconds and immersion in oil at 20 ° C for 20 seconds).
No failure was observed even after 100 cycles (as one cycle), and the connection reliability between the conductive (wiring) patterns was equal to or higher than that obtained by the conventional copper plating through-hole method.

FIG. 5 is a sectional view showing the structure of a main part of a circuit board according to the third embodiment. In FIG. 5, reference numeral 1 denotes a first circuit board on which an electrically connected surface 1a is selectively projected, and 8 denotes an electrically connected surface 8a facing the connected surface 1a of the first circuit board 1. Is a flexible second circuit board. Here, the circuit board 1 is a through-hole type formed by using a double-sided copper foil-clad board made of glass-epoxy resin as an insulator, and the connected surface 1a has conductive bumps ( It is formed of a copper foil portion that is deformed and protruded by the selective pressing action of a conductive resin composition containing silver powder as a conductive agent) 1c.

That is, after the copper foil is deformed and protruded, the copper foil is patterned together with other wiring patterns. The second circuit board 8 is provided with a wiring pattern including a surface 8a to be connected on a surface of a polyimide resin film 8b.

Further, numeral 3 is interposed between the surfaces to be joined of the circuit boards 1 and 8 to selectively electrically connect (conductivity) 3a between both surfaces 1a and 8a. And an anisotropic conductive adhesive layer for electrically and mechanically joining the non-electrical joining surfaces 3b.

In the case of this configuration, a so-called rigid circuit board and a flexible circuit board are electrically connected to each other with high reliability.
Not only mechanical connection and joining can be formed, but also electrical and mechanical connection and joining can be easily performed, which greatly contributes to practical use of a rigid-flexible circuit board.

In each of the above embodiments, a similar circuit board can be obtained even if the electrically connected surface (convex portion) of the first circuit board is formed of a plating layer or a conductive resin layer.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0046]

According to the first to third aspects of the present invention, the anisotropic conductive adhesive layer interposed between the joining surfaces of the circuit boards has the opposite electrically connected surfaces. Are selectively protruded, and the corresponding connected surfaces are pressurized and crimped preferentially, and selectively exhibit conductivity in the pressurized and crimped region, and the opposing connected surfaces establish electrical connection. Has formed. On the other hand, in regions other than the preferential pressure / compression bonding region, the circuit boards are mechanically joined and integrated by the insulating anisotropic conductive adhesive layer.

That is, while the opposing connected surfaces form a reliable and highly reliable electrical connection, the electrical connection is reliably insulated and separated and joined together with high mechanical strength. A circuit board is provided.

According to the fourth aspect of the present invention, a circuit board suitable for the configuration of the circuit board can be provided with a high yield.

According to the fifth and sixth aspects of the present invention,
In addition to simplifying the interlayer connection process, a highly reliable high-density wiring type or high-density mounting type circuit board can be provided with high yield and low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a main part of a circuit board according to a first embodiment.

FIGS. 2A and 2B schematically show a manufacturing mode of a first circuit board. FIG. 2A shows a laminate in which a laminate of a copper foil having conductive bumps formed thereon, an insulating sheet, and a copper foil is sandwiched between flexible boards. -A cross-sectional view showing a state in which they are arranged, and (b) is a cross-sectional view showing a state when they are integrated by applying pressure.

FIG. 3 is a cross-sectional view illustrating a main configuration of a circuit board used for the configuration of the circuit board according to the second embodiment.

FIG. 4 is a sectional view showing a configuration of a main part of a circuit board according to a second embodiment.

FIG. 5 is a sectional view showing a configuration of a main part of a circuit board according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st circuit board 1a ... Electrical connection part 1b ... Insulating sheet 1c ... Conductive bump 2 ... 2nd circuit board 2a ... Electrical connection part 3 ... Different Anisotropic conductive adhesive layer 3a: conductive areas of anisotropic conductive adhesive layer 4a, 4b: copper foil 5a, 5b: flexible plate 6: copper foil-clad laminate 7 (7a, 7b, 7c)... First and second circuit boards (also used) 7a ″, 7b ″, 7c ″... Electrically connected parts (projections) 8....

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ identification symbol FI H05K 3/36 H05K 3/36 Z 3/40 3/40 K (58) Field surveyed (Int.Cl. ⁷ , DB name) H05K 3/46 H05K 3/36 H05K 1/11 H05K 3/40

Claims (6)

(57) [Claims] 1. A conductive projection may be penetrated in a thickness direction.
Selects an electrically connected surface on at least one surface by
A protruding portion, the surface of which is metal
A first circuit board covered with a layer, a second circuit board having an electrically connected face opposing a protruded connected face of the first circuit board, and a joined face of the two circuit boards An anisotropic conductive adhesive layer that is interposed therebetween and selectively electrically connects the two connected surfaces, and insulates and electrically mechanically bonds the non-electrically bonded surfaces. A circuit board, comprising: 2. An electric connection surface of a first circuit board,
2. The circuit board according to claim 1 , wherein the circuit board is formed of a plating layer or a conductive resin. Wherein either hard-to-deform on one main surface of the first conductor foil
Forming a substantially conical conductive bump; laminating an insulating sheet through which the tip of the conductive bump can penetrate, on the conductive bump forming surface; Laminating and placing a second conductor foil on at least one of the two conductor foils in the laminated arrangement, press-molding by inserting a flexible plate outside at least one of the two conductor foils, and forming a conductive bump on the flexible plate side with the conductive bump. A method of manufacturing a circuit board, comprising: a step of forming a conductor foil-clad substrate in which a conductor foil in a contact area is deformed and protruded; and a step of patterning a conductor foil of the conductor foil-clad substrate. Method. 4. A conductive projection may be penetrated in a thickness direction.
Selects an electrically connected surface on at least one surface by
A protruding portion, the surface of which is metal
A step of manufacturing a core substrate covered with a layer, a step of laminating and arranging an anisotropic conductive adhesive layer on the connection surface side of the core substrate, Positioning and arranging a circuit board having an electrically connected surface corresponding to the electrically connected surface of the core substrate, and pressurizing the positioned and arranged laminate to correspond between the two connected surfaces. Selectively making the anisotropic conductive adhesive layer region conductive and bonding and integrating the same. 5. A conductive projection penetrating in a thickness direction.
Selects electrically connected surface on at least one side
A protruding portion protruding from the metal layer,
Manufacturing a first circuit board covered with: a step of laminating and arranging an anisotropic conductive adhesive layer on the connection side of the core substrate; and an anisotropic conductive adhesive layer. A step of positioning and arranging a circuit board having an electrically connected surface corresponding to the electrically connected surface of the core substrate; and pressing the positioned and positioned laminate to correspond between the two connected surfaces. Selectively making the anisotropic conductive adhesive layer region conductive and bonding and integrating the same. 6. The step of manufacturing the core substrate, A hardly deformable and substantially conical conductive material is provided on one main surface of the first conductive foil.
Forming a sex bump; The tip of the conductive bump penetrates the conductive bump forming surface.
A step of laminating and placing an insertable insulating sheet; A step of laminating and arranging a second conductor foil on the insulating sheet
About A flexible material is provided on at least one of the outer sides of the conductor foils in the laminated arrangement.
Press-molded with a flexible plate interposed, conductive on the flexible plate side
Deformed and protruded the conductor foil in the area in contact with the conductive bump
A step of forming a conductor foil-clad substrate, Patterning the conductor foil of the conductor foil-clad substrate
6. The method according to claim 4, further comprising the steps of:
3. The method for manufacturing a circuit board according to 1.