JP2001189561A - Multilayer wiring board and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer wiring board which is free from the risk of producing a recess on the forming parts of through holes in wiring layers on both main faces of the board, a trouble is not caused in the connection and mounting of an LSI chip and a solder ball, a different wiring film is laminated on a wiring film, more multiple layers can easily be formed and the multilayer wiring films have necessary thickness by fine patterns. SOLUTION: The wiring films 3 are formed on both faces of the insulating film 2 and the through holes 4 of a base sheet 1 where the through holes 4 connecting the wiring films 3 and 3 on both faces are filled with conductive materials 5. A laminating sheet 6 having metallic protrusions 8 protruded to one side in positions corresponding to the through holes 4 and having the wiring films 7 on the other side is laminated on the main face of one side of the base sheet 1 or the main faces of both sides so that the metallic protrusions 8 are brought into contact with the conductive materials 5 buried in the through holes 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a multilayer wiring board for connecting electronic devices and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional example of a method for manufacturing a multilayer wiring board for high-density mounting will be described in the order of steps with reference to FIGS. (A) As shown in FIG. 9A, a copper-clad laminate a is prepared, and a connection hole b is formed in the laminate a by drilling or laser processing. c is an insulating sheet (thickness of 50 to 100 μm) forming a base of the laminated plate a, and d and d are copper foils (9 to 18 μm thick) formed on both surfaces of the insulating sheet c.

(B) Next, as shown in FIG. 9B, a copper plating layer (thickness: 10 μm) is formed on the entire surface by electroless plating and subsequent electrolytic plating. (C) Next, as shown in FIG. 9C, the hole b is filled with an insulating resin f such as epoxy.

(D) Next, as shown in FIG. 9 (D), both main surfaces of the laminate a are mechanically polished to smooth the surface, and then the copper plating layer g is again electrolessly plated. And electrolytic plating subsequent thereto. Thus, the insulating resin f filling the hole b is covered with the copper plating layer g. (E) Next, as shown in FIG. 9E, a wiring film h is formed by patterning the copper plating layers g, d, and e on both main surfaces of the laminate a. This etching is a selective etching using a resist film applied, exposing and developing it to form a mask pattern, and using the mask pattern as a mask. For example, a ferric chloride solution is used as an etchant. This is done by spraying. After the selective etching, the resist film used as a mask is removed.

(F) Next, as shown in FIG.
After coating the insulating resin i on both main surfaces of the laminated board a, the insulating resin i is provided with an opening j serving as a through hole.
Is formed using, for example, a laser beam. At this time, it is necessary to wash with an aqueous solution of potassium permanganate in order to remove the resin residue attached to the surface of the copper foil d in the hole b. (G) Next, as shown in FIG.
A copper plating layer k is formed on both main surfaces by electroless plating and electrolytic plating.

(H) Next, as shown in FIG.
The circuit 1 is formed by patterning the copper plating layers k on both main surfaces of the laminate a. This patterning is performed by selectively etching the resist film using a mask patterned by exposure and development as a mask. Of course, after the selective etching, the resist film used as a mask is removed. (I) Next, as shown in FIG.
Are selectively covered with solder resist m. Thereby, the multilayer wiring board n is completed.

(J) On this multilayer wiring board n, an LSI chip o is connected via solder bumps p and the like, an underfill material is filled, and a solder ball q is mounted. This multilayer wiring board n can also be used as a motherboard.

[0008]

The above-mentioned multilayer wiring board n has the following problems. The first problem is that the adhesion between the surface of the insulating resin f filling the hole b and the copper plating layer g is poor, and poor adhesion is likely to occur. At the time of mounting, if the solder ball q is mounted here or the LSI chip o is connected, there is a possibility that it will fall off. Therefore, in order to avoid that,
In addition, it is necessary to design so that the positions of the solder ball q mounting portion and the LSI chip o do not overlap, and this is a design constraint, which is one factor that restricts the high density.

The second problem is that the copper plating layer k is formed on a layer having a hole j, so that the surface becomes concave on the hole j (concave), which further increases. This hinders the formation of the wiring layer, and is a factor that restricts the achievement of further multilayering.

A third problem is that, as described above, the copper plating layer k is formed on the portion where the hole j exists, as described above.
It is important to obtain a sufficient thickness because it tends to be thin on the step, but there is a problem that it is difficult. This is because the copper plating layer k is formed by electroless plating and subsequent electrolytic plating. However, electroless plating has a low film formation rate, and electrolytic plating tends to have a variation in film thickness due to the relationship of electrolytic distribution. This is because it is difficult to secure a sufficient film thickness even on the step portion. This has been one of the factors restricting the miniaturization of the wiring circuit.

The present invention has been made to solve such a problem, and there is no possibility that a wiring layer on both main surfaces of a substrate will have a dent on a portion where a through hole (hole) is formed. There is no risk of interfering with the connection and mounting of the LSI chip and the solder ball, it is easy to laminate another wiring film on the wiring film to make it more multilayered, and each multilayer wiring film is finely divided. It is an object of the present invention to provide a novel multilayer wiring board which can be formed to have a required thickness in a simple pattern and a method for manufacturing the same.

[0012]

According to a first aspect of the present invention, there is provided a multi-layer wiring board comprising a base sheet having a wiring film formed on both sides of an insulating film and a through hole formed between the wiring films on both sides. A laminated sheet having a through hole filled with a conductive material, a metal projection protruding on one side at a position corresponding to the through hole on one or both main surfaces of the base sheet, and a wiring film on the other side. Are laminated so that the metal projections are in contact with the conductive material filling the through holes, or another laminated sheet is further laminated on the laminated sheet.

Therefore, according to the multilayer wiring board of the first and second aspects, the laminated sheet having the metal projection on one or both main surfaces of the base sheet on the side opposite to the side on which the wiring film is formed is provided. Since the metal protrusions are laminated so as to be connected to the conductive material filling the holes of the laminated sheet, the wiring film formed on the laminated sheet does not become concave even in the portion corresponding to the hole, Can be smooth. In addition, there is no need to form the foil to be the wiring film by electroless plating and subsequent electroless plating, and it is easy to make the film thickness uniform to the required thickness, so that fine wiring is possible. is there.

Further, since the metal projections of the laminated sheet are directly connected to the conductive material filling the holes of the base sheet, the adhesion between the holes and the metal projections can be enhanced. Therefore, the reliability of the interlayer connection can be increased. Further, by further laminating the laminated sheets, the multilayering of the wiring board can be advanced by a relatively simple process.

In the method for manufacturing a multilayer wiring board according to claims 6 and 7, the through holes of the base sheet are filled with a conductive material, and a laminated sheet is formed on one or both main surfaces of the base sheet.
The metal protrusions are laminated so as to be in contact with the conductive resin filling the through holes, and a wiring film is formed by patterning the metal film of the laminated sheet, or further,
It is characterized by the following.

According to the method for manufacturing a multi-layer wiring board according to the sixth and seventh aspects, a base sheet and a laminated sheet are prepared, and selective etching necessary for forming a wiring film, and lamination of sheets are performed. A multilayer wiring board can be obtained by a simple process. Further, by further increasing the number of laminated sheets to be laminated, the multilayer wiring board can be easily multi-layered, and further higher integration of the multilayer wiring board can be achieved.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The multilayer wiring board according to the present invention is basically formed by forming a wiring film on both sides of an insulating film and forming a through hole for connecting the wiring films on both sides of the base sheet. A hole is filled with a conductive material, a laminated sheet having a metal projection protruding on one side at a position corresponding to the through hole on one or both main surfaces of the base sheet and having a wiring film on the other side. The base sheet is manufactured using the same copper-clad laminate as in the conventional example shown in FIGS. 9 and 10, while the metal projection is in contact with the conductive material filling the through hole. The difference from the conventional example is that the through holes are filled with a conductive material.As in the conventional case, the through holes are filled with an insulating resin, and then, electroless plating and subsequent electrolytic plating are performed. It is not necessary to form a copper film with Is that. As the conductive material, a copper paste or a silver paste is optimal.

The laminated sheet has, for example, a three-layer structure in which a metal projection made of copper or a copper alloy is formed on one main surface of an etching barrier layer and a wiring film is formed on the other main surface of the etching barrier layer. It may be. The etching barrier layer can be composed of, for example, nickel (for example, 2 μm in thickness) or silver (for example, 0.5 μm in thickness). Then, it is preferable to apply an insulating film on the surface of the etching barrier layer on the side where the metal projections are formed so as to insulate and separate the respective metal projections. Incidentally, such a laminated sheet has already been disclosed by the applicant of the present invention in Japanese Patent Application No. 11-28927.
No. 7 has already been proposed.

Further, the laminated sheet may have a two-layer structure composed of metal projections made of copper or a copper alloy and a wiring film made of silver.

In the multilayer wiring board of the present invention, basically, the through-holes of the base sheet are filled with a conductive material, and a laminated sheet is formed on one or both main surfaces of the base sheet, and the metal protrusions are formed on the laminated sheet. It can be manufactured by laminating in contact with the conductive resin filling the holes, and forming a wiring film by patterning the metal film of the laminated sheet. Also,
Laminating another laminated sheet on the laminated sheet laminated on the base sheet and patterning the metal film on the surface of the laminated sheet to form a wiring film, or further laminating the laminated sheet to further increase the number of layers The number of layers may be increased to increase the number of layers.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. 1 (A) to 1 (D) and 2 (F) to 2 (H) are sectional views showing one embodiment of a method for manufacturing a multilayer wiring board according to the present invention in the order of steps.

(A) First, as shown in FIG. 1A, a laminated sheet 1 is prepared. The laminated sheet 1 is prepared by preparing a copper-clad laminate in which copper foil 3 is laminated on both main surfaces of a sheet-shaped insulating resin 2, and through holes 4 are formed in the laminated sheet by drilling or laser processing. The wiring film is formed by patterning by selectively etching the foil 3. The method of manufacturing the base sheet 1 will be described later with reference to FIG. Further, the base sheet manufactured by the method shown in FIG. 4 may be used. This manufacturing method will be described later in detail.

(B) Next, as shown in FIG. 1 (B), the through holes 4 are filled with a conductive material 5. A conductive paste made of, for example, copper or silver is suitable as the conductive material. (C) Next, as shown in FIG. 1C, two laminated sheets 6 are prepared, and each laminated sheet 6 is made to face both main surfaces of the base sheet 1.

The structure and manufacturing method of the laminated sheet 6 will be described later in detail with reference to FIG. 5, but one of the principal surfaces has a thickness of, for example, about 12 μm made of copper or a copper alloy to be a wiring film. On one surface of a metal foil (or a metal foil made of silver) 7, a projection 8 made of, for example, copper corresponding to the through hole 4 of the base sheet 1 is formed.
An adhesive sheet 9 thinner than the height of the projection 8 is adhered to the surface on which the protrusions 8 are formed, and the top of each projection 8 protrudes from the adhesive sheet 9. The direction of the laminated sheet 6 facing both main surfaces of the base sheet 1 is such that the protruding surface of the projection 8 is opposed to the main surface of the base sheet 1, and the laminated sheet 6 is aligned with each of the projections 8. The base sheet 1 is aligned with the corresponding through holes 4.

(D) Next, as shown in FIG. 1 (D), the laminated sheets 6 are laminated on both main surfaces of the base 1 and integrated by pressing. At this time, the metal projection 8
Penetrates into the conductive material 5 filling the hole 4 and is in a strongly connected state. As a result, the electrical connection between them can be perfectly established. Of course, at this time, the metal foil 7 is not dented at the portion corresponding to the hole 4.

(E) Next, as shown in FIG. 2 (E), a wiring film is formed by patterning the metal foil 7 of each of the laminated sheets 6. This patterning is performed by forming a mask pattern by applying, exposing, and developing a resist film, etching by using the mask pattern as a mask, and then removing the resist film used as the mask. For this selective etching, for example, a method of spray etching with a ferric chloride aqueous solution from both sides is preferable.

(F) Next, as shown in FIG. 2 (F), a solder resist film 10 is selectively formed on the surface of each laminated sheet 6. Numeral 11 denotes concave portions formed by selectively forming the solder resist film 10. Each concave portion 11 has a portion to which a solder bump forming an electrode of an LSI chip of the wiring film 7 is connected or a portion to which a solder ball is formed. Is exposed. Upon completion of this step, the multilayer wiring board 12 is completed. This multilayer wiring board 12 corresponds to one embodiment of the multilayer wiring board of the present invention.

(G) FIG. 2 (G) shows the multilayer wiring board 12 described above.
Shows a state in which the LSI chip 13 is mounted, 14 is a solder bump, and 15 is a solder ball for connecting the multilayer wiring board 12 to a motherboard (not shown). Although the multilayer wiring board 12 is an example of a multilayer wiring board for a semiconductor package, it can be used as a motherboard.

According to the present multilayer wiring board 12, since the through holes 4 are filled with the conductive material 5, after filling the through holes of the copper clad laminate, the copper for forming the wiring film is formed by electroless plating and subsequent electrolytic plating. It is no longer necessary to form a film, and there is no danger that it is difficult to make the copper film sufficiently thick or that the film thickness varies. In addition, the copper film for forming the wiring film is not dented at a portion corresponding to the hole 4. Therefore, the wiring film 7 having a required thickness and a fine pattern can be relatively easily formed without any trouble.

Moreover, since the metal projections 8 of the laminated sheet 6 are connected to the conductive material 5 filling the through holes 4 so as to enter the conductive material 5, the laminated sheet 6 and the base sheet 1 are connected to each other.
And the electrical connection between the layers is more reliably ensured, and the multilayer wiring board 12 which is simple to manufacture and has high reliability can be provided.

FIGS. 3A to 3C show the base sheet 1 described above.
3A to 3C are cross-sectional views illustrating one example of the manufacturing method of FIG. (A) As shown in FIG. 3A, a laminate having a three-layer structure of copper-clad on both sides is prepared as a base of the base sheet 1. The laminate is obtained by laminating a copper foil 3 on both main surfaces of a sheet-shaped insulating resin 2.

(B) Next, as shown in FIG. 3B, the copper foil 3 on both main surfaces of the base sheet 1 is patterned by selective etching to form a wiring film 3 forming a circuit.
Selective etching for patterning is to apply a resist film, pattern it by exposure and development,
The etching is performed by etching the copper foil 3 using the patterned resist film as a mask. After the etching is completed, the resist film is removed. ,

(C) Next, as shown in FIG. 3 (C), the through-hole 4 is formed by using, for example, a drill or by laser processing. The diameter of the through hole 4 is, for example, 0.1 to 0.3.
mm.

FIGS. 4A to 4D show the base sheet 1 described above.
FIG. 9 is a cross-sectional view showing another example of the manufacturing method in the order of steps. (A) As shown in FIG. 4 (A), similarly to the case shown in FIG.
Prepare as a mother. The laminate is obtained by laminating a copper foil 3 on both main surfaces of a sheet-shaped insulating resin 2.

(B) Next, as shown in FIG. 4B, the through holes 4 are formed by using a drill, for example, or by laser processing. The diameter of the through hole 4 is, for example, 0.1 to 0.3.
mm. (C) Next, the entire surface is subjected to an electroless copper plating process, and subsequently, the entire surface is subjected to an electrolytic plating process.
As shown in (C), a copper film 3a is formed.

(D) Next, the copper film 3a is selectively etched to form a wiring film as shown in FIG. This is performed by photolithography using a resist film. The base sheet 1 used for the multilayer wiring board of the present invention may be manufactured by any method.

FIGS. 5A to 5D are cross-sectional views showing one example 6 of the method of manufacturing the laminated sheet in the order of steps. (A) As shown in FIG. 5A, silver (for example, 12 μm thick)
A laminate is prepared by laminating a metal layer (thickness, for example, 100 μm) 8 made of copper or a copper alloy on the surface of a metal base material 7 made of m).

(B) Next, as shown in FIG. 5B, a resist film 1 is formed on the surface of the metal layer 8 made of copper or copper alloy.
8 is selectively formed. This is used as an etching mask at the time of etching for forming the metal projection 8, and it goes without saying that the etching is performed by applying, exposing, and developing the resist film 18.

(C) Next, the metal layer 18 is selectively etched by using the resist film 18 as a mask to form the metal protrusions 8.
Is removed. FIG. 5C shows a state after the resist film 18 is removed. Note that, for example, an alkaline etchant is used for the etching. (D) Next, as shown in FIG. 5D, an adhesive sheet 9 thinner than the height of the projections 8 is attached to the surface of the metal base member 7 on which the metal projections 8 are formed. The head is made to protrude from the surface of the sheet 9. When such a laminated sheet 6 is used, the metal film 7 made of silver, which hits the surface of the laminated sheet 6, is selectively etched to form the wiring film 7, so that the wiring film 7 on the surface of the multilayer wiring board is formed. Is composed of silver.

FIGS. 6A to 6D are sectional views showing a method of manufacturing another example 6a of a laminated sheet in the order of steps. The laminated sheet 6a of this example has one more layer than the laminated sheet 6 shown in FIG. (A) As shown in FIG. 6A, an etching stop layer made of nickel (thickness, for example, 2 μm) or silver (thickness, for example, 0.5 μm) is formed on the surface of a metal base material (thickness, for example, 18 μm) 7 made of copper. A laminate having a three-layer structure is prepared by laminating a metal layer (thickness of, for example, 100 μm) 8 made of copper or a copper alloy on the surface of the etching stop layer 19.

(B) Next, as shown in FIG. 6B, a resist film 1 is formed on the surface of the metal layer 8 made of copper or copper alloy.
8 is selectively formed. This is used as an etching mask at the time of etching for forming the metal projection 8, and it goes without saying that the etching is performed by applying, exposing, and developing the resist film 18.

(C) Next, the metal layer 18 is selectively etched using the resist film 18 as a mask to form the metal protrusions 8.
Is removed. For the etching, for example, an alkaline etching solution is used. During this etching, the etching stop layer 19 serves to prevent the metal base material 7 made of copper from being attacked by the etching. FIG.
(C) shows the state after the removal of the resist film 18.

(D) Next, as shown in FIG. 6D, an adhesive sheet 9 thinner than the height of the projections 8 is attached to the surface of the metal base member 7 on which the metal projections 8 are formed. The head of the projection 8 is made to protrude from the surface of the sheet 9.

7 and 8 are sectional views showing another embodiment of the method for manufacturing a multilayer wiring board according to the present invention in the order of steps. FIG.
8A to 8F show a method for manufacturing a laminated sheet, and FIG.
(A) to (C) show a lamination method using the laminated sheet. (A) First, as shown in FIG.
A metal plate 21 made of copper of about 0 μm is prepared.

(B) Next, as shown in FIG. 7B, a photosensitive insulating resin layer 22 is applied, and the photosensitive resin layer 22 is patterned by exposure and development. Reference numeral 23 denotes a hole formed by the patterning.
7) is formed at a position to be formed. (C) Next, the entire surface of the insulating resin layer 22 is subjected to an electroless copper plating treatment (a copper plating thickness of, for example, 0.5 μm), and thereafter, a plating resist pattern is selectively formed. A wiring film 24 made of a copper film (having a thickness of, for example, 20 μm) is formed by plating, and thereafter, the resist pattern is removed. Thereafter, a copper film (thickness: 0. 5 μm), each wiring film 2 is etched.
4 are separated and independent from each other. FIG. 7C shows a state after the etching. For this etching, for example, a release agent is used.

(D) Next, as shown in FIG. 7D, the wiring film 24 is selectively covered with an insulating layer 25 so that an opening 26 is formed in a portion where a connection terminal portion is to be formed. . (E) Next, a protruding microball 27 having a multilayer structure made of, for example, nickel / gold is formed by electrolytic plating.
This electrolytic plating is preferably performed with nickel, for example, at 50 μm and then with gold, for example, at 0.3 μm.

(F) Next, as shown in FIG. 7 (F), the metal plate 28 is formed by selectively etching the copper plate 21, and then the surface on which the metal plate 28 is formed is formed. To the adhesive layer 29. Thereby, the laminated sheet 30 is completed.

FIGS. 8A to 8C show a method of forming a multilayer wiring board by laminating two laminated sheets 30 on both main surfaces of the base sheet 1 shown in FIG. (A) The base sheet 1 and two laminated sheets 30 to be laminated on both main surfaces thereof are prepared, and each of the laminated sheets 30 is disposed on both main surfaces of the base sheet 1, and the respective metal projections 28 are formed.
And the conductive material 5 that fills the holes 4 of the base sheet 1.

(B) Next, as shown in FIG. 8B, the laminated sheets 30 are laminated on both main surfaces of the base sheet 1 and integrated by pressing. At this time, the metal projection 28 enters into the conductive material 5 filling the hole 4 and is firmly connected. As a result, the electrical connection between them can be perfectly established. Thus, another embodiment 31 of the multilayer wiring board of the present invention is completed.

(C) Next, as shown in FIG. 8C, the LSI chip 13 is mounted on the multilayer wiring board 12, and further, solder balls are mounted. 14 is a solder bump, 15
Are solder balls for connecting the multilayer wiring board 12 to a motherboard (not shown). In addition, the present multilayer wiring board 31
Is an example of a multilayer wiring board for a semiconductor package, but it can be used as a motherboard in the same manner as the multilayer wiring board 12 in FIG.

In each of the above embodiments of the multilayer wiring board, the laminated sheet 6 or 30 is laminated on both main surfaces of the base sheet 1, but the laminated sheet 5 is formed on only one side of the base sheet 1. Alternatively, the present invention can be implemented in a mode in which 30 layers are stacked.

According to the present invention, by further laminating the laminated sheet 6 or 29 sequentially on both sides or one side of the multilayer wiring boards 12 and 31, it is possible to further increase the multilayer wiring board.

[0053]

According to the present invention, a laminated sheet having a metal projection on one or both main surfaces of a base sheet on a side opposite to a side on which a wiring film is formed is provided. Since the wiring film is laminated so as to be connected to the conductive material that fills the hole, the wiring film formed on the laminated sheet can be smooth without being concave even in the portion corresponding to the hole. In addition, it is not necessary to form the foil serving as the wiring film of the base sheet by electroless plating and subsequent electroless plating, and it is easy to make the film thickness uniform to the required thickness. Is possible.

Further, since the metal projections of the laminated sheet are directly connected to the conductive material filling the holes of the base sheet, the adhesion between the holes and the metal projections can be increased. Therefore, the reliability of the interlayer connection can be increased. Further, by further laminating the laminated sheets, the multilayering of the wiring board can be advanced by a relatively simple process.

[Brief description of the drawings]

FIGS. 1A to 1D are cross-sectional views sequentially showing steps (A) to (D) of one embodiment of a method for manufacturing a multilayer wiring board according to the present invention.

FIGS. 2 (E) to 2 (G) are sectional views showing steps (E) to (G) of one embodiment of the method for manufacturing a multilayer wiring board according to the present invention in order.

FIGS. 3A to 3C are cross-sectional views showing one example of a method of manufacturing a base sheet according to the embodiment in the order of steps.

FIGS. 4A to 4D are cross-sectional views showing another example of the method of manufacturing the base sheet according to the embodiment in the order of steps.

FIGS. 5A to 5D are cross-sectional views showing one example of a method of manufacturing the laminated sheet 6 in the order of steps.

FIGS. 6A to 6D are cross-sectional views showing a method of manufacturing another example 6a of a laminated sheet in the order of steps.

FIGS. 7A to 7F are cross-sectional views illustrating a method of manufacturing a laminated sheet used in another embodiment of the method of manufacturing a multilayer wiring board according to the present invention in the order of steps.

8 (A) to 8 (C) show another embodiment of the method for manufacturing a multilayer wiring board according to the present invention, which is a method for manufacturing a multilayer wiring board using a multilayer sheet manufactured by the manufacturing method shown in FIG. 7; It is sectional drawing which shows a method in order of a process.

FIGS. 9A to 9E are cross-sectional views sequentially showing steps (A) to (E) of one conventional example of a method for manufacturing a multilayer wiring board.

FIGS. 10F to 10J are cross-sectional views sequentially showing steps (F) to (J) of the conventional example of the method for manufacturing a multilayer wiring board.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base sheet, 2 ... Insulating resin, 3 ... Wiring film (metal film), 4 ... Through-hole, 5 ... Conductive material,
6 ... laminated sheet, 7 ... metal foil (metal film), 8
..Metal protrusions, 12 ... multilayer wiring boards, 21 ...
Metal plate, 22: photosensitive insulating resin layer, 24: wiring film, 25: insulating layer, 28: metal protrusion, 29
..Adhesive layer, 30 ... Laminated sheet, 31 ... Multilayer wiring board.

Continued on the front page F term (reference) 5E317 AA24 BB12 BB14 BB22 CC22 CC25 CC32 CC33 CD15 CD18 CD25 CD27 CD32 GG03 GG14 5E346 AA06 AA32 AA35 AA43 CC32 CC39 DD02 DD12 DD32 EE09 EE13 EE18 FF07 FF15 GG18 GG17 GG15 GG18 GG18 GG18 HH26

Claims (7)

[Claims] 1. A base sheet in which a wiring film made of metal is formed on both surfaces of an insulating film, and a through hole for forming a through hole for electrically connecting between the wiring films on both surfaces is filled with a conductive material. A laminated sheet having a metal projection protruding on one side and a wiring film on the other side at a position corresponding to the through-hole on one or both main surfaces of the sheet, wherein the metal projection has the through-hole. A multilayer wiring board, which is laminated so as to be in contact with the above-mentioned conductive material for filling the wiring. 2. A base sheet in which a wiring film made of metal is formed on both surfaces of an insulating film, and a through-hole formed in the wiring film on both surfaces to electrically connect the wiring films is filled with a conductive material. A laminated sheet having a metal projection protruding on one side and a wiring film on the other side at a position corresponding to the through-hole on one or both main surfaces of the sheet, wherein the metal projection has the through-hole. A multilayer wiring board, which is laminated so as to be in contact with the above-mentioned conductive material, and further laminated with another laminated sheet on each of the laminated sheets or one of the laminated sheets. 3. The multilayer wiring board according to claim 1, wherein the conductive material filling the through holes is a conductive paste of copper or silver. 4. The multilayer wiring board according to claim 1, wherein the laminated sheet has a two-layer structure including a metal protrusion made of copper or a copper alloy and a wiring film made of silver. . 5. The laminated sheet has a three-layer structure in which a metal protrusion made of copper or a copper alloy is formed on one main surface of an etching barrier layer and a wiring film is formed on the other main surface of the etching barrier layer. The multilayer wiring board according to claim 1, 2 or 3, wherein: 6. A step of filling a through-hole of a base sheet, in which a wiring film made of metal is formed on both surfaces of an insulating film and a through-hole penetrating between the wiring films on both surfaces is formed, with a conductive material; On one or both main surfaces of the base sheet, a laminated sheet having a metal projection protruding on one side and a metal film on the other side at a position corresponding to the through hole, wherein the metal projection is 5. The method according to claim 1, further comprising the steps of: laminating the conductive film so as to be in contact with the conductive material filling the holes; and forming a wiring film by patterning a metal film of the laminated sheet.
Or a method of manufacturing a multilayer wiring board for manufacturing the multilayer wiring board according to 5. 7. A base sheet in which a wiring film made of metal is formed on both surfaces of an insulating film, and a through-hole for forming a through-hole for electrically connecting the wiring films on both surfaces is filled with a conductive material; On one or both main surfaces of the base sheet, a laminated sheet having a metal projection protruding to one side at a position corresponding to the through hole and having a wiring film on the other side, wherein the metal projection is A step of laminating the laminated sheet so as to be in contact with the conductive material filling the through hole; and a step of laminating one or more laminated sheets similar to the laminated sheet on the surface of the laminated sheet. 5. A method for manufacturing a multilayer wiring board for manufacturing the multilayer wiring board according to 2, 3, or 4.