JP4279811B2 - Multilayer wiring board manufacturing method and wiring board forming metal plate - Google Patents

Description

The present invention relates to a method for manufacturing a multilayer wiring board and a metal plate for forming a wiring board, and more particularly to a method for manufacturing a multilayer wiring board for manufacturing a highly integrated and highly reliable wiring board having fine vias, and a fine via. The present invention relates to a highly integrated and highly reliable metal plate for forming a wiring board.

In order to highly integrate the wiring board, it is necessary to make the wiring board multi-layered and to form the connection between the upper and lower wiring films with high reliability and fineness.
By the way, conventionally, a multilayer wiring board has, for example, a wiring board in which a wiring film is formed on both sides or a multilayer structure as a base (hereinafter sometimes referred to as a “core board”), and the wiring board as the base is drilled, for example. The upper and lower wiring connection holes are formed by, for example, a plating film is formed on the inner peripheral surface of the upper and lower wiring connection holes, and the plating film is used as the upper and lower wiring connection wiring film. A copper foil or resin coat in which holes for wiring connection are filled with silver paste or insulating paste, and another interlayer connection bump is provided on both sides of the wiring board used as the base, and insulating resin is laminated. There is a technique of laminating the copper foils, drilling with laser light, and forming vias by plating. These are called build-up methods, and are methods for producing multilayer wiring boards, which is a technique for highly integrating substrates.
A technique for forming a through hole of a multilayer wiring board by a laser (for example, excimer laser) processing method is described in Japanese Patent Application Laid-Open Nos. 2000-326081 and 2000-349437.
JP 2000-326081 A, JP 2000-349437 A

However, according to the above-described conventional method for manufacturing a high-density multilayer wiring board, there is a problem that it is difficult to achieve high integration. This is because it is difficult to reduce the diameter of the upper and lower wiring connection holes. Considering mass productivity and yield, it is practically difficult for the core substrate to have a hole diameter of 0.3 mm or less, and the existence of a relatively large hole connecting hole between upper and lower wirings restricts high integration. .

That is, the upper and lower wiring connection holes themselves occupy a part of the core substrate, so that the large hole diameter directly restricts the degree of integration of the wiring boards. Is a factor that necessitates detouring with respect to other wiring films.Therefore, the larger the hole diameter, the larger the number of wiring films that must be detoured, and the longer the detouring length of the detouring wiring film. It also restricts the degree of integration indirectly . In order to enable high-density wiring, the single-layer surface for patterning a circuit needs to be a clean surface that is free of defects. Since it is handled, there is a problem that defects such as scratches, dust adhesion, and dents are likely to occur. However, due to the fine wiring, there has been a problem that even fine defects cannot be tolerated.

The present invention has been made to solve such problems, and a novel method of manufacturing a multilayer wiring board capable of obtaining a highly integrated multilayer wiring board in which fine vias are realized in all layers. And it aims at providing the metal plate for novel wiring board formation.

According to a first aspect of the present invention, there is provided a method for manufacturing a multilayer wiring board , wherein a wiring film is formed on at least one surface using a multilayer metal plate, and a wiring film or a metal plate for forming a wiring film is formed on the other surface. A plurality of types of basic wiring boards having a multi-layer wiring structure in which interlayer insulation is made by interlayer connection by bumps made of metal are prepared, and a plurality of different types of the above-mentioned plurality of types of basic wiring boards are included. The basic wiring board is laminated.

A method for manufacturing a multilayer wiring board according to a second aspect is the method for manufacturing a multilayer wiring board according to the first aspect, wherein the uppermost one and the lowermost one among a plurality of basic wiring boards to be laminated are A wiring film is formed on the surface of the wiring layer, and a wiring film forming metal layer is formed on the other surface. The uppermost one of the plurality of basic wiring substrates and the lowermost one are wiring films. The plurality of basic wiring boards are laminated so that the surface on which the forming metal layer is formed faces outward, and then the wiring film forming metal layers of the uppermost and lowermost basic wiring boards are simultaneously patterned. Thus, the uppermost and lowermost wiring films are formed.

According to a third aspect of the present invention, there is provided a multilayer wiring board manufacturing method comprising: a step of forming a reinforcing layer on one surface of a multilayer metal plate for forming a wiring substrate; and a step from a surface opposite to the reinforcing layer of the multilayer metal plate. It includes at least a step of laminating other members and a step of peeling the reinforcing layer thereafter.

According to a fourth aspect of the present invention, there is provided a multilayer wiring board manufacturing method comprising: a step of forming a reinforcing layer on one surface of a multilayer metal plate for forming a wiring substrate; and a step from a surface opposite to the reinforcing layer of the multilayer metal plate. It includes at least a patterning step and a step of laminating other members, and then a step of peeling the reinforcing layer.

A method for producing a multilayer wiring board according to a fifth aspect is the method for producing a multilayer wiring board according to the third aspect or the fourth aspect, wherein the reinforcing layer is formed by a heat resistant film provided with a release layer. And

A method for producing a multilayer wiring board according to a sixth aspect is the method for producing a multilayer wiring board according to the fifth aspect , wherein the heat resistant film is a polyphenylene sulfide resin film, a polyetherimide resin film, a polyphenylene oxide resin film, a liquid crystal polymer. It consists of a film, a polyimide resin film, or a polyetheretherketone resin film.

The wiring board forming metal plate of the seventh aspect has a three-layer structure, and in the wiring board forming metal plate in which metal bumps for interlayer connection are formed on one surface, the surface opposite to the one surface is later. A release layer and a heat-resistant film are laminated in advance on a surface to be a wiring film.

According to the method for manufacturing a multilayer wiring board of the first aspect , a plurality of types of basic wiring boards having a multilayer wiring structure are prepared, and a plurality of types including the different types of the plurality of types of basic wiring boards are included. Therefore, it is possible to easily obtain a multilayer wiring board having, for example, 4 to 10 layers or more.

According to the multilayer wiring board manufacturing method of the second aspect , after laminating a plurality of basic wiring boards, the uppermost layer and the lowermost wiring are simultaneously patterned by patterning the uppermost layer and the lowermost wiring film forming metal layer. A film can be formed, the number of wiring film forming steps can be reduced, and the price of the multilayer wiring board can be reduced.

According to the method for manufacturing a multilayer wiring board of the third aspect , a thin multilayer metal plate with low mechanical strength can be reinforced with a reinforcing layer to improve workability and reduce the defect rate. . In addition, since the surface of the metal layer for forming the wiring film is continuously protected by the reinforcing layer from the initial process to the wiring film patterning process, the surface is used in, for example, a bump etching process, a pressing process, and an inspection process. There is no such thing as a scratch on the wiring film, and the formed wiring film is not defective. In addition, the surface of the metal layer for forming the wiring film is protected from the chemical solution, and dust is prevented from adhering to the surface.

According to the method for manufacturing a multilayer wiring board of the fourth aspect , it is possible to receive the same effects as those enjoyed by the method for manufacturing the multilayer wiring board of the third aspect .

According to the method for manufacturing a multilayer wiring board of the fifth aspect , the same effects as those enjoyed by the method for manufacturing the multilayer wiring board of the third aspect or the fourth aspect can be enjoyed. Furthermore, when the reinforcing layer is made of a metal such as nickel or copper, it takes time since etching is required for the peeling. However, as in the method of manufacturing the multilayer wiring board of the fifth aspect , the peeling layer and the heat resistance When the reinforcing layer is formed of a film, when the wiring film patterning process is started, it is sufficient to simply peel off the heat-resistant film, thereby simplifying the process.

According to the method for manufacturing a multilayer wiring board of the sixth aspect , it is possible to receive the same effects as those enjoyed by the method for manufacturing a multilayer wiring board of the fifth aspect .

According to the wiring board forming metal plate of the seventh aspect , a thin multilayer metal plate having a low mechanical strength can be reinforced with a reinforcing layer to improve workability and to reduce the defect rate. . In addition, since the surface of the metal layer for forming the wiring film is continuously protected by the heat-resistant film from the first step to the wiring film patterning step, for example, the surface is scratched in the pressing process. And there is no defect in the formed wiring film. In addition, the surface of the metal layer for forming the wiring film is protected from the chemical solution, and dust is prevented from adhering to the surface. Further, when the reinforcing layer is made of a metal such as nickel or copper, it takes time since etching is required to remove them. However, like the metal plate for wiring board formation of the seventh aspect , the peeling layer and the heat resistance In the case of the film, when the wiring film patterning process is started, it is sufficient to simply peel off the heat-resistant film, thereby simplifying the process.

One of the methods for producing a multilayer wiring board of the present invention is that a multilayer metal plate is used to form a wiring film on at least one surface, and a wiring film or a metal plate for wiring film formation is formed on the other surface. A plurality of types of basic wiring boards having a multi-layer wiring structure in which interlayer insulation is made by metal bumps are included, and different types of the plurality of types of basic wiring boards are included. In such a manufacturing method, a wiring film is formed on one surface as the uppermost one and the lowermost one among the plurality of basic wiring substrates to be laminated. The one having the metal layer for forming the wiring film formed on the other surface is selected, and the uppermost one of the plurality of basic wiring substrates and the lowermost one are the wiring film forming metal layer forming side. The plurality of the surfaces are facing outward. The basically wiring board is laminated, then it is preferable to form the uppermost layer and the lowermost wiring layer by simultaneously patterning the wiring film forming metal layer basic circuit board bottom and the top.

Another method for producing a multilayer wiring board according to the present invention includes a step of forming a reinforcing layer on one surface of a multilayer metal plate for forming a wiring substrate, and a surface of the multilayer metal plate opposite to the reinforcing layer. A step of laminating the other member from the above, and then a step of peeling the reinforcing layer, or a step of forming a reinforcing layer on one surface of the multilayer metal plate for forming a wiring board, In such a manufacturing method, it has at least a patterning step from the surface opposite to the reinforcing layer of the multilayer metal plate and a step of laminating other members, and then a step of peeling the reinforcing layer. The reinforcing layer is preferably formed of a heat-resistant film provided with a release layer, and the heat-resistant film further comprises a polyphenylene sulfide resin film, a polyetherimide resin film, a polyphenylene Kisaido resin film, a liquid crystal polymer film, it is the best form a polyimide resin film or polyether ether ketone resin film.

The wiring board forming metal plate used in the production of the multilayer wiring board of the present invention has a three-layer structure, and the wiring board forming metal plate having metal bumps for interlayer connection formed on one side thereof, The form in which a release layer and a heat-resistant film are laminated in advance on the opposite surface, which will later become a wiring film, is the best.

Hereinafter, the present invention will be described in detail according to illustrated embodiments.
1 (A) to (D), FIGS. 2 (E) to (H) and FIGS. 3 (I) to (K) are steps (A) to (A) of the first embodiment of the method for manufacturing a multilayer wiring board of the present invention. It is sectional drawing which shows (K) in order.
(A) First, as shown in FIG. 1A, multilayer metal plates 1a and 1b are prepared.
The multilayer metal plates 1a and 1b are both thick on one main surface of a bump forming metal layer 2 made of a copper foil having a thickness of, for example, 100 μm, with an etching stop layer 3 made of a nickel layer having a thickness of, for example, 2 μm. For example, a wiring film forming metal layer 4 made of, for example, 18 μm copper foil is laminated.

(B) Next, for the multilayer metal plate 1a, the bump forming metal layer 2 and the etching stop layer 3 are patterned by selective etching to form bumps 2a for connecting the upper and lower wirings. In this selective etching, the etching stop layer 3 prevents the wiring film 4a from being etched when the bump forming metal layer 2 is etched. After the bump forming metal layer 2 is selectively etched, etching is performed on the etching stop layer 3 using copper, which is a material for forming the bump forming metal layer 2 and the wiring film forming metal layer 4, as a mask.

Thereafter, an insulating film 5 made of, for example, resin is bonded to the bump 2a forming surface so that only the top of the bump 2a is exposed from the surface of the film 5.
On the other hand, for the multilayer metal plate 1b, the wiring film 4a is formed by patterning the metal layer 4 for forming the wiring film. At this time, the etching stop layer 3 prevents the bump forming metal layer 2 from being etched. FIG. 1 (B) shows a multi-layer metal plate 1a completing the formation of the wiring layer 4a, a multilayer metal plate 1 b finishing the formation of the insulating film 5.
The subsequent formation of the wiring film 4a and the bump 2a of the multilayer metal plate 1 is also performed by the method described above.

(C) Next, the multilayer metal plates 1a and 1b are laminated by connecting the bumps 2a of the multilayer metal plate 1a to the wiring film 4a of the multilayer metal plate 1b. FIG. 1C shows a state after the lamination.
(D) Next, a bump 2a is formed by patterning the bump forming metal layer 2 and the etching stop layer 3 of the multilayer metal plate 1b by selective etching. FIG. 1D shows a state after the bump 2a is formed.

(E) Next, the insulating film 5 made of, for example, resin is bonded to the surface on which the bump 2a is formed so that only the top of the bump 2a is exposed from the surface of the insulating film 5. And the multilayer metal plate 1c is prepared as a new multilayer metal plate. The multi-layer metal plate 1c is formed by patterning the metal layer 4 for forming the multi-layer metal plate 1 of the multi-layer metal plate 1 having the same structure as the multi-layer metal plates 1a and 1b having the three-layer structure shown in FIG. 4a is formed. FIG. 2 (E) shows a state in which the bump 2a formation side surface of the multilayer metal plates 1a and 1b is exposed to the surface on the wiring film 4a formation side of the multilayer metal plate 1c after the formation of the wiring film 4a. .

(F) Next, as shown in FIG. 2F, the bump 2a of the multilayer metal plate 1a is connected to the wiring film 4a of the multilayer metal plate 1b, and the multilayer metal plate 1c is laminated on the multilayer metal plate 1b.
(G) Next, a bump 2a is formed by patterning the bump forming metal layer 2 and the etching stop layer 3 of the multilayer metal plate 1b by selective etching, and then the bump 2a is formed of a resin, for example. The insulating film 5 is bonded so that only the tops of the bumps 2a are exposed from the film 5.

Thereafter, a multilayer metal plate 1d is prepared as a new multilayer metal plate. The multi-layer metal plate 1d is formed by patterning the metal layer 4 for forming a multi-layer metal plate having the same structure as the multi-layer metal plates 1a, 1b and 1c having the three-layer structure shown in FIG. The film 4a is formed. FIG. 2 (G) shows a state in which the surface on the bump 2a formation side of the multilayer metal plates 1a, 1b, 1c after formation of the insulating film 5 faces the wiring film 4a formation surface of the new multilayer metal plate 1d. Indicates.

(H) Next, as shown in FIG. 2 (H), the bump 2a of the multilayer metal plate 1b is connected to the wiring film 4a of the multilayer metal plate 1c, and the multilayer metal plate 1a, 1b, 1c is laminated with the multilayer metal. The plates 1d are stacked.
(I) Next, a bump 2a is formed by patterning the bump forming metal layer 2 and the etching stop layer 3 of the multilayer metal plate 1e by selective etching, and then the bump 2a is formed of a resin, for example. The insulating film 5 is bonded so that the bump 2a is pierced and the tip portion protrudes.

Thereafter, a multilayer metal plate 1e is prepared as a new multilayer metal plate. The multi-layer metal plate 1e is formed by patterning the metal layer 4 for forming a multi-layer metal plate having the same structure as the multi-layer metal plates 1a and 1b having the three-layer structure shown in FIG. Is formed. FIG. 3 (I) shows a state in which the surface on the bump 2a formation side of the multilayer metal plates 1a to 1d after formation of the insulating film 5 faces the wiring film 4a formation surface of the new multilayer metal plate 1e. .

(J) Next, a bump 2a is formed by patterning the bump-forming metal layer 2 and the etching stop layer 3 of the multilayer metal plate 1e by selective etching. The insulating film 5 is bonded so that only the tops of the bumps 2a are exposed from the surface of the film 5. Thereafter, the wiring film forming metal thin plate 6 made of copper is connected to the bump 2a and laminated on the bump 2a forming surface side. FIG. 3J shows a state after the lamination.
(K) Next, the wiring film forming metal layer 4 of the multilayer metal plate 1a (the uppermost multilayer metal plate in FIGS. 1, 2 and 3) and the wiring film forming metal thin plate 6 are patterned by selective etching. Thus, the wiring films 4a and 6a are formed. The wiring film 4a becomes the uppermost wiring film and the wiring film 6a becomes the lowermost wiring film.

Summarizing the manufacturing method of this multilayer wiring board, the bump 2a is formed by patterning the bump forming metal layer 2 and the etching stop layer 3 on the basis of the multilayer metal plate 1a, and an insulating film is formed on the bump 2a formation surface. Another multi-layer metal plate in which the wiring film 4a is formed by patterning the wiring film forming metal layer 4 after the 5 is pierced by the bump 2a and bonded so that the tip thereof protrudes from the surface of the insulating film 5 The laminating step of connecting the wiring film 4a of 1b to the bump 2a of the multilayer metal plate 1a and laminating the multilayer metal plate 1a and 1b is always performed on the formation surface of the bump 2a of one multilayer metal plate 1. The wiring film 4a forming surface of the multilayer metal plate 1 is repeatedly stacked to form a multilayer, and finally, the uppermost and lowermost wiring film forming metal layer 4 and the wiring film forming metal thin plate 6 are patterned. Top surface and the wiring layer 4a of the bottom surface Te, is intended to form the wiring film forming metal sheet 6a, by increasing the number of repetitions of the above-mentioned lamination process, it is possible to increase the number of layers of the wiring board.

According to this multilayer wiring board manufacturing method, the connection between the upper and lower wirings is made in the insulating substrate forming the base, a metal plating film for connection between the upper and lower wirings is formed on the inner peripheral surface, and then the holes are formed. Since the bump 2a formed by patterning the bump forming metal layer 2 of the multilayer metal plate 1 is used as the connecting means between the upper and lower wirings without following the conventional technique of filling, the area of the portion necessary for the connection between the upper and lower wirings is changed to the diameter. For example, 0.1 mm or less can be made extremely narrower than before.
The ability to narrow the connection between the upper and lower wirings not only has a direct effect on improving the degree of integration by narrowing the area occupied by itself, but also has an adverse effect on other wiring films that necessitate detours. Indirect effect is also brought about. In other words, the indirect effect of reducing the adverse effect on other wiring films can reduce the number of wiring films that are forced to be detoured. Also, the wiring film that is forced to be detoured is shortened. Therefore, the degree of integration can be remarkably improved.

In addition, since the lamination process is repeated in such a manner that the wiring film 4a formation surface of another multilayer metal plate 1 is superimposed on the formation surface of the bump 2a of one multilayer metal plate 1, the multilayer process is sequentially performed. The number of layers of the multilayer metal plate can be arbitrarily increased depending on the number, and a wiring board having a very high degree of integration can be provided.
The wiring substrates 1a, 1b, 1c,... To be laminated may be laminated after forming the wiring film forming metal layer 4a and the bump 2a and adhering the insulating film 5. .

In the first embodiment, the wiring film 4a on the multilayer metal plate 1a or 1b is formed on the bump forming metal layer 2 via the etching stop layer 3 on the wiring film forming metal layer 3. This is prepared by preparing a base material and selectively etching and patterning the wiring film forming metal layer 3, but the wiring film 4a can also be formed by plating. Then, if the wiring film 4a is formed by plating, side etching as in the case of patterning the wiring film forming metal layer 3 by photoetching does not occur. Therefore, formation of a fine and highly integrated wiring film 4a is formed. Is possible.

Specifically, a substrate in which an etching stop layer 3 is laminated on a bump forming metal layer 2 is prepared as a base material, and a photoresist film, for example, is selectively formed on the surface of the etching stop layer 3 on the side opposite to the bump forming metal layer. A method of forming the wiring film 4a by plating with a metal such as copper using the photoresist film as a mask is preferable. The wiring film may be formed directly on the surface of the etching stop layer by plating, but a thin plating base layer made of, for example, copper or the like is formed on the surface of the etching stop layer, and the wiring film 4a is formed on the plating base layer. May be formed by plating using a photoresist film as a mask. In this case, after forming the wiring film 4a, it is necessary to etch the thin plating base layer using the wiring film 4a as a mask.

FIGS. 4 to 11 are for explaining a second embodiment of the method for manufacturing a multilayer wiring board according to the present invention. In this embodiment, a basic wiring board 50 for forming a multilayer wiring board by processing raw materials is shown. A plurality of types (for example, 50α, 50β, 50γ, 50δ) are prepared and laminated by combining any of the plurality of types of basic wiring substrates to form a multilayer wiring substrate 51 (for example, 51a, 51b, 51c, 51d). FIGS. 4 to 7 illustrate a method of manufacturing each of the basic wiring boards or the basic wiring board, and FIGS. 4A to 4D are basic. FIG. 5 shows a second example 50β of the basic wiring board, FIG. 6 shows a third example 50γ of the basic wiring board, and FIG. Shows a fourth example 50δ of the basic wiring board.

First, the manufacturing method of the first example 50α will be described with reference to FIGS.
(A) First, as shown in FIG. 4 (A), a multilayer metal plate 1a is prepared. The multilayer metal plate 1a may be the same as the multilayer metal plate 1a shown in FIG. That is, a wiring film made of a copper foil having a thickness of, for example, 18 μm is provided on one main surface of the bump forming metal layer 2 made of a copper foil having a thickness of 100 μm via an etching stop layer 3 made of a nickel layer having a thickness of, for example, 2 μm. A laminate of the forming metal layer 4 is prepared.

(B) Next, the bump forming metal layer 2 and the etching stop layer 3 of the multilayer metal plate 1a are patterned by selective etching to form bumps 2a for connecting the upper and lower wirings. After the bump forming metal layer 2 is selectively etched, etching is performed on the etching stop layer 3 using copper, which is a material for forming the bump forming metal layer 2 and the wiring film forming metal layer 4, as a mask.
Thereafter, an insulating film 5 made of, for example, resin is bonded to the bump 2a forming surface so that only the bump top portion is exposed to the bump 2a. Thereafter, as shown in FIG. 4B, the metal thin plate 6 for forming a wiring film made of copper, for example, is allowed to face the surface of the multilayer metal plate 1a on which the tops of the bumps 2a protrude.

(C) Next, as shown in FIG. 4C, the wiring film forming metal thin plate 6 is connected to the bump 2a and laminated on the bump 2a formation surface side.
(D) Next, the wiring films 4a and 6a are formed by patterning the wiring film forming metal layer 4 of the multilayer metal plate 1a and the wiring film forming metal thin plate 6 by selective etching. As a result, the basic wiring substrate 1α is completed, and the wiring film 4a becomes the upper wiring film and the wiring film 6a becomes the lower wiring film.

FIG. 5 shows a basic wiring substrate 50β, which is a step shown in FIG. 4D in the manufacturing method shown in FIG. 4, and does not selectively etch the wiring film forming metal layer 4, that is, the upper wiring layer. The film 4a can be formed by forming only the wiring film 6a by performing selective etching on the wiring film forming metal thin plate 6 without forming the film 4a.

FIG. 6 shows a basic wiring board 50γ. The basic wiring board 50γ can be formed in the same process as the process shown in FIGS.
FIG. 7 shows a basic wiring board 50δ. The basic wiring substrate 50δ is formed with an insulating film 5 on the surface of the basic wiring substrate 50δ shown in FIG. 6 on the bump 2a formation side so that only the top of the bump 2a is exposed from the insulating film 5, The wiring film forming metal layer 4 can be formed by patterning by photoetching to form the wiring film 4a.

FIGS. 8 to 11 are for explaining different examples 51a to 51d of multilayer wiring boards manufactured by combining the above basic wiring boards 50α, 50β, 50γ, and 50δ. A) shows basic wiring boards 50γ and 50α used for the construction of the multilayer wiring board 51a, and FIG. 8B shows a state in which the basic wiring board 50γ is laminated on the upper surface of the basic wiring board 50α. Then, the uppermost wiring film forming metal layer 4 and the lowermost wiring film forming metal thin plate 6 of the laminate in the state shown in FIG. 8B are patterned by, for example, photoetching to form the wiring film 4a, When 6a is formed, a four-layer multilayer wiring board 51a is completed.

9A shows basic wiring boards 50γ, 50α, and 50γ used for the configuration of the multilayer wiring board 51b, and FIG. 9B shows the basic wiring boards above and below the basic wiring board 50α. A state in which 50γ and 50γ are stacked in a direction in which the bump 2a side is directed to the basic wiring substrate 50α side is shown. Then, when the wiring films 4a and 4a are formed by patterning the uppermost and lowermost wiring film forming metal layers 4 and 4 of the laminated body in the state shown in FIG. The multilayer wiring board 51b is completed.

FIG. 10A shows basic wiring boards 50γ, 50α, 50δ, and 50γ used for the configuration of the multilayer wiring board 51b, and FIG. 10B shows a basic with the bump 2a side facing upward. A basic wiring board 50δ with the bump 2a side facing upward is laminated on the basic wiring board 50γ, and a basic wiring board 50α is laminated on the basic wiring board 50δ. A state is shown in which a basic wiring board 50γ is laminated so that the bump 2a formation side faces downward with respect to the basic wiring board 50α. Then, when the wiring films 4a and 4a are formed by patterning the uppermost and lowermost wiring film forming metal layers 4 and 4 of the laminated body in the state shown in FIG. A multi-layered wiring substrate 51c is completed.

11A shows basic wiring boards 50γ, 50δ, 50α, 50δ, and 50γ used for the configuration of the multilayer wiring board 51b, and FIG. 11B shows the direction in which the surface on the bump 2a side faces upward. A basic wiring board 50δ with the bump 2a side facing upward is laminated on the basic wiring board 50γ, and the basic wiring board 50α is laminated on the basic wiring board 50δ. Further, a basic wiring substrate 50δ with the bump 2a and insulating film 5 forming side facing downward is laminated on the basic wiring substrate 50α, and the bump 2a and insulating film 5 forming side is further stacked on the basic wiring substrate 50δ. A state in which a basic wiring board 50γ oriented downward is laminated is shown. Then, when the wiring films 4a and 4a are formed by patterning the uppermost and lowermost wiring film forming metal layers 4 and 4 of the laminated body in the state shown in FIG. The multilayer wiring board 51d is completed.

As described above, a plurality of types of basic wiring boards 50 constituting a multilayer wiring board by processing raw materials are prepared, and a plurality of types of basic wiring boards are arbitrarily combined. There may be a form in which the multilayer wiring boards 51a, 51b, 51c, 51d are manufactured by stacking. By doing in this way, the multilayer wiring board 51 of arbitrary number of layers (for example, 4-10) can be obtained.
Also according to the second embodiment of the method for manufacturing a multilayer wiring board of the present invention, substantially the same effect can be obtained if it can be obtained by the first embodiment.

FIGS. 12A to 12E and FIGS. 13F to 13I are cross-sectional views sequentially showing steps (A) to (I) of the third embodiment of the method for manufacturing a multilayer wiring board of the present invention. .
(A) Prepare a multilayer metal plate 20a in which a wiring film forming metal layer 23 made of copper foil is laminated on one surface of a bump forming metal layer 21 made of copper foil via an etching stop layer 22 made of nickel, The wiring film 23a is formed by patterning the wiring film forming metal layer 23 by selective etching. At this time, the etching stop layer 22 serves to prevent the bump-forming metal layer 21 from being etched. FIG. 12A shows a state after the formation of the wiring film 23a.

(B) Next, as shown in FIG. 12B, a thin copper film 24 is plated on the surface of the multilayer metal plate 20a on the wiring film 23a formation side. The copper film 24 prevents the etching stop layer (25) made of nickel formed on the copper film 24 in the next step from being etched when the etching stop layer 22 is selectively etched later. Fulfill. Note that it is not impossible to omit the step of forming the copper film 24 by precisely controlling the etching thickness. Therefore, this step is not essential.

(C) Next, as shown in FIG. 12C, an etching stop layer 25 made of nickel is formed on the surface of the multilayer metal plate 20a on the wiring film 23a formation side by plating.
(D) Next, as shown in FIG. 12D, a bump forming metal layer 26 made of copper is formed on the surface of the multilayer metal plate 20a on the wiring film 23a forming side by laminating or plating the clad.

(E) Next, as shown in FIG. 12E, bumps 21a are formed by patterning by selective etching with respect to the bump forming metal layer 21 and the etching stop layer 22 of the multilayer metal plate 20a.
(F) Next, on the surface of the multilayer metal plate 20a on the bump 21a formation side, the insulating film 27 is bonded to the bump 21a so that the tip of the insulating film 27 protrudes, and then the insulating film The wiring film forming metal thin plate 28 is laminated on the bump 27 a so as to be connected to the bump 21 a. FIG. 13F shows a state after bonding the thin metal film 28 for forming the wiring film.

(G) Next, as shown in FIG. 13G, bumps 26 a are formed by patterning by selective etching with respect to the bump-forming metal layer 26 and the etching stop layer 25.
(H) Next, as shown in FIG. 14H, the wiring films 23 a are electrically separated by etching the copper film 24.

(I) Next, on the surface of the multilayer metal plate 20a on the bump 26a formation side, the insulating film 30 is bonded to the bump 21a so that the tip of the insulating film 30 protrudes from the bump 21a. A wiring film forming metal thin plate 31 is laminated on the bump 26a. FIG. 13 (I) shows a state after the metal thin plate 31 for forming a wiring film is bonded.

Thereafter, although not shown, a wiring film is formed by patterning by selective etching with respect to the metal thin films 29 and 31 for forming the wiring film. Then, it is possible to obtain a wiring board having three layers and interlayer connection made by the bumps 21a and 26a. Although an example of a three-layer wiring board has been described here, it can be applied to a multilayer wiring board having more than that. That is, FIG. 13F is a pattern obtained by patterning the metal layer 28 (not shown), and a bump 26a shown in FIG. 13H that is bonded to the tip so that its tip protrudes (not shown). By combining these, a multilayer board having three or more layers can be obtained.

Even with this multilayer wiring board manufacturing method, the area required for the connection between the upper and lower wirings can be made extremely narrow with a diameter of, for example, 0.1 mm or less, and the area occupied by the connection part between the upper and lower wirings itself is reduced. In addition to providing a direct effect on improving the degree of integration, it is possible to obtain an indirect effect of reducing the adverse effect on other wiring films that necessitates detouring. In other words, the indirect effect of reducing the adverse effect on other wiring films can reduce the number of wiring films that are forced to be detoured. Also, the wiring film that is forced to be detoured is shortened. The effect that you can.

(Modification)
14 (A) and 14 (B) show partial steps (A) and (B) of the modified example obtained by modifying the third embodiment of the method for manufacturing the multilayer wiring board of the present invention shown in FIGS . 12 and 13. It is sectional drawing shown. In this modification, an etching stop layer 22 made of nickel is formed on a bump forming metal layer 21 made of copper as a multilayer metal plate, and a plating base layer 30 made of copper is formed on the etching stop layer 22. Using a resist film selectively formed on the plating base layer 30 as a mask, copper is plated 20 to form a wiring film 23a having a predetermined pattern. FIG. 14A shows the multilayer metal plate 20b, and FIG. 14B shows a state after the etching stop layer 25 made of nickel is formed on the multilayer metal plate 20b. This corresponds to the step shown in FIG. Thereafter, the steps after the step shown in FIG. 12D in the second embodiment shown in FIGS. 12 and 13 are performed.

Also according to this example, the same effect as that of the third embodiment shown in FIGS. 12 and 13 can be obtained, and a pattern with higher accuracy can be formed than the etching pattern.

15A to 15E are sectional views showing a fourth embodiment of the method for manufacturing a multilayer wiring board according to the present invention in the order of steps.
(A) As shown in FIG. 15A, as a multilayer metal plate, an etching stop layer 22 made of nickel is laminated on a bump forming metal layer 21 made of copper, and a wiring made of copper is formed on the etching stop layer 22. A multilayer metal plate having five layers in which a film forming metal layer 23 is laminated, a layer 41 made of nickel is formed on the wiring film forming metal layer 23, and a copper layer 42 is formed on the layer 41. Prepare 40. The nickel layer 41 and the copper layer 42 of the multilayer metal plate 40 form a reinforcing layer 43 that is peeled off later, and the multilayer metal plate 40 is bent due to insufficient mechanical strength and is liable to be defective. Play a role in preventing. Also, by continuously protecting the surface of the metal layer for forming the wiring film from the first process to the wiring film patterning process, the surface is scratched in the bump etching process, the pressing process, etc. This serves to prevent the occurrence of defects in the formed wiring film. Furthermore, it plays the role which protects the metal layer surface for wiring film formation from a chemical | medical solution, and the adhesion of the dust to this surface.

The multilayer metal plate 40 has a nickel layer on the surface of the wiring film forming metal layer 23 of the three-layered multilayer metal plate including the bump forming metal layer 21, the etching stop layer 22, and the wiring film forming metal layer 23. 41, and further, a copper layer 42 may be plated on the surface of the nickel layer 41, or a bump forming metal layer 21, an etching stop layer 22, a wiring film forming metal layer 23, a nickel layer You may form by laminating | stacking the clad of five layers which consists of 41 and the copper layer 42. FIG.

(B) Next, as shown in FIG. 15B, the bump forming metal layer 21 is patterned by selective etching to form bumps 21a.
(C) Next, as shown in FIG. 15C, the insulating film 44 is bonded to the surface of the multilayer metal plate 40 where the bumps 21a are formed so that the bumps 21a pierce and the tips protrude.
(D) After that, the wiring film forming metal thin plate 45 is connected to the bumps 21 a and laminated on the insulating film 44. FIG. 15D shows a state after bonding the thin metal film 28 for forming the wiring film. In this state, the mechanical strength of the multilayer metal plate 40 is stronger than in the state shown in FIG. 15B, and there is almost no possibility of bending and bending to cause a failure.

(E) Thereafter, as shown in FIG. 15E, the wiring film can be formed by patterning by selective etching on the wiring film forming metal layer 23 and the wiring film forming metal thin plate 45, as shown in FIG. The reinforcing layer 43 is peeled off by a selective etching method.

According to the fourth embodiment, it is possible to reinforce the multi-layered metal plate that is thin and has low mechanical strength with the reinforcing layer 43, to improve workability and to reduce the defect rate. Further, by continuously protecting the surface of the metal layer for forming the wiring film from the initial process to the wiring film patterning process, the surface is scratched in, for example, the bump etching process, the pressing process, the inspection process, etc. It is possible to prevent the occurrence of defects in the formed wiring film by eliminating the sticking. Furthermore, the surface of the metal layer for forming a wiring film can be protected from a chemical solution, and dust can be prevented from adhering to the surface.

16A to 16E are cross-sectional views showing a fifth embodiment of the method for manufacturing a multilayer wiring board according to the present invention in the order of steps.
(A) As shown in FIG. 16A, as a multilayer metal plate, an etching stop layer 22 made of nickel is laminated on a bump forming metal layer 21 made of copper, and a wiring made of copper is formed on the etching stop layer 22. A multilayer metal plate 60 on which the film-forming metal layer 23 is laminated is prepared. A heat resistant film 62 having a release layer 61 is laminated on the metal layer 23 for forming a wiring film of the multilayer metal plate 60.

The release layer 61 and the heat-resistant film 62 form a reinforcing layer 63 to be peeled later, and prevent the multilayer metal plate 60 from being bent and bent easily due to insufficient mechanical strength. Fulfill. In addition, by continuously protecting the surface of the metal layer for forming the wiring film from the initial process to the wiring film patterning process, the surface is not damaged, for example, during the pressing process. This serves to prevent defects in the wiring film formed. Furthermore, it plays the role which protects the metal layer surface for wiring film formation from a chemical | medical solution, and the adhesion of the dust to this surface.

In addition, the peeling layer 61 is formed in the thickness of 1-3 micrometers, for example using an organic type agent. Examples of the organic agent include one or more selected from a nitrogen-containing organic compound, a sulfur-containing organic compound, a carboxylic acid, or a polymer compound.
Among these, the nitrogen-containing organic compound includes a nitrogen-containing organic compound having a substituent. Specifically, as the nitrogen-containing organic compound, 1,2,3-benzotriazole, which is a triazole compound having a substituent, carboxy It is preferable to use benzotriazole or the like. Further, as the sulfur-containing organic compound, it is preferable to use mercaptobenzothiazole, thiocyanuric acid or the like. As the carboxylic acid, it is particularly preferable to use a monocarboxylic acid, and it is particularly preferable to use oleic acid, linoleic acid, linolenic acid, or the like. Further, it may be a silicone resin, a fluorine resin, or the like that has heat resistance and is peelable.

Moreover, the heat resistant film 62 uses a polymer and is formed to a thickness of, for example, 10 to 100 μm. As the polymer, for example, a polyphenylene sulfide resin film, a polyetherimide resin film, a polyphenylene oxide resin film, a liquid crystal polymer film, a polyimide resin film, or a polyether ether ketone resin film is suitable for this purpose.

(B) Next, as shown in FIG. 16B, the bump forming metal layer 21 is patterned by selective etching to form bumps 21a.
(C) Next, as shown in FIG. 16C, the insulating film 44 is bonded to the bump 21a formation surface of the multilayer metal plate 40 so as to be pierced by the bump 21a and to protrude its tip.
(D) After that, the wiring film forming metal thin plate 45 is connected to the bumps 21 a and laminated on the insulating film 44. FIG. 16D shows a state after bonding the thin metal film 28 for forming the wiring film. In this state, the mechanical strength of the multilayer metal plate 40 is stronger than in the state shown in FIG. 16 (B), and there is almost no possibility of bending and bending to cause a failure.

(E) Thereafter, as shown in FIG. 16E, the wiring film can be formed by patterning by selective etching on the wiring film forming metal layer 23 and the wiring film forming metal thin plate 45. Then, the reinforcing layer 63 is peeled off.

According to the fifth embodiment, the same effect as that of the fourth embodiment can be enjoyed, and in particular, the effect that the process is simplified can be enjoyed. That is, when the reinforcing layer 43 is made of a metal such as nickel or copper as in the fourth embodiment, it takes time to remove the etching, but as in the fifth embodiment, When the reinforcing layer 63 is composed of the release layer 61 and the heat resistant film 62, when entering the wiring film patterning process (when shifting from FIG. 16D to FIG. 16E), the heat resistant film is It is only necessary to peel off, and the process is simplified accordingly.

The present invention is widely applied to a multilayer wiring board manufacturing method for manufacturing a highly integrated and highly reliable wiring board having fine vias, and a highly integrated and highly reliable wiring board forming metal plate having minute vias. There is industrial applicability.

(A)-(D) are sectional drawings which show (A)-(D) in process (A)-(K) of the 1st Example of the manufacturing method of the multilayer wiring board of this invention in order of a process. (E)-(H) is sectional drawing which shows (E)-(H) of process (A)-(K) of the 1st Example of the manufacturing method of the multilayer wiring board of this invention in order of a process. (I)-(K) is sectional drawing which shows (I)-(K) of process (A)-(K) of the 1st Example of the manufacturing method of the multilayer wiring board of this invention in order of a process. (A)-(D) are sectional drawings which show the manufacturing method of an example of the basic wiring board used for 2nd Embodiment of the manufacturing method of the multilayer wiring board of this invention in order of a process. It is sectional drawing which shows another example of the basic wiring board used for 2nd Embodiment of the manufacturing method of the multilayer wiring board of this invention. It is sectional drawing which shows another example of the basic wiring board used for 2nd Embodiment of the manufacturing method of the multilayer wiring board of this invention. It is sectional drawing which shows another example of the basic wiring board used for 2nd Embodiment of the manufacturing method of the multilayer wiring board of this invention. FIGS. 8A and 8B are diagrams for explaining an example of a four-layer multilayer wiring board. FIG. 8A shows two basic wiring boards constituting the multilayer wiring board. Indicates a state in which the two basic wiring boards are laminated. FIGS. 8A and 8B are diagrams for explaining an example of a six-layer multilayer wiring board. FIG. 8A shows three basic wiring boards constituting the multilayer wiring board. Indicates a state in which the three basic wiring boards are laminated. FIGS. 8A and 8B are diagrams for explaining an example of an eight-layer multilayer wiring board. FIG. 8A shows four basic wiring boards constituting the multilayer wiring board, and FIG. Indicates a state in which the four basic wiring boards are laminated. FIGS. 8A and 8B are diagrams for explaining an example of a multilayer wiring board having 10 layers, and FIG. 8A shows five basic wiring boards constituting the multilayer wiring board, and FIG. Indicates a state in which the five basic wiring boards are laminated. (A)-(E) is sectional drawing which shows (A)-(E) of process (A)-(I) of the 3rd Example of the manufacturing method of this invention multilayer wiring board in order of a process. (F)-(I) is sectional drawing which shows (F)-(I) of process (A)-(I) of the 3rd Example of the manufacturing method of the multilayer wiring board of this invention in order of a process. (A), (B) is sectional drawing which shows process (A), (B) of the modification of the said 3rd Example in order. (A)-(E) is sectional drawing which shows process (A)-(E) of the 4th Example of the manufacturing method of this invention multilayer wiring board in order. (A)-(E) is sectional drawing which shows process (A)-(E) of the 5th Example of the manufacturing method of the multilayer wiring board of this invention in order.

Explanation of symbols

1a to 1e ... multilayer metal plate, 2 ... metal layer for bump formation,
2a: bumps for connection between upper and lower wirings, 3 ... etching stop layer,
4 ... Metal layer for wiring film formation, 4a ... Wiring film, 5 ... Insulating film,
8 ... Metal thin plate for wiring film formation, 8a ... Wiring film, 20a ... Multi-layer metal plate,
21 ... Bump forming metal layer, 21a ... Bump, 22 ... Etching stop layer, 23a ... Wiring film, 26 ... Bump forming metal layer, 26a ... Bump,
27 ... Insulating film, 28 ... Metal thin plate for wiring film formation, 28a ... Wiring film,
30 ... Insulating film, 31 ... Metal thin plate for wiring film formation, 31a ... Wiring film,
50α to 50δ ... basic wiring board, 51a to d ... multilayer wiring board,
60 ... multi-layer metal plate, 61 ... release layer, 62 ... heat resistant film,
63: Reinforcing layer.

Claims (8)

Prepare at least two multilayer metal plates comprising a bump forming metal layer, an etching stop layer, and a wiring film forming metal layer in this order,
(I) In one multilayer metal plate of the multilayer metal plates, the bump forming metal layer and the etching stop layer are patterned by selective etching to form upper and lower wiring connection bumps; A step of obtaining a first basic wiring substrate by laminating an insulating film made of a resin on the formation surface of the bump for connecting between the upper and lower wirings so that the top of the bump for connecting between the upper and lower wirings is exposed;
(Ii) obtaining a second basic wiring substrate on which a wiring film is formed by patterning a metal layer for forming a wiring film of another multilayer metal plate among the multilayer metal plates by selective etching;
(Iii) a step of laminating the side of the first basic wiring board on which the tops of the upper and lower wiring connection bumps are exposed and the side of the second basic wiring board on which the wiring film is formed;
(Iv) The bump forming metal layer and the etching stop layer of the second basic wiring substrate are patterned by selective etching to form upper and lower wiring connection bumps, and the upper and lower wiring connection bumps And a step of obtaining a third basic wiring board by laminating an insulating film made of resin on the forming surface so that the tops of the bumps for connecting the upper and lower wirings are exposed. Further, the step of laminating the wiring film of the second basic wiring board prepared separately on the exposed top of the bump for connecting the upper and lower wirings of the third basic wiring board and performing the step (iv) at least once The method for producing a multilayer wiring board according to claim 1, which is repeated . A step of obtaining a first multilayer wiring board by laminating a metal thin film for forming a wiring film on the exposed top of the bump for connecting the upper and lower wirings;
3. The manufacturing of a multilayer wiring board according to claim 2, further comprising a step of patterning the wiring film forming metal layer and / or the wiring film forming metal thin plate of the first multilayer wiring board by selective etching. Method. Further, a step of obtaining a fourth basic wiring board by laminating a thin metal sheet for forming a wiring film on the exposed top of the bump for connecting the upper and lower wirings of the first basic wiring board prepared separately;
Obtaining a wiring film by patterning the metal layer for forming a wiring film and / or the metal thin film for forming a wiring film of the fourth basic wiring board by selective etching;
Including a step of laminating a wiring film formed on at least one surface of the fourth basic wiring board so that the top of the upper and lower wiring connection bumps of the third basic wiring board is exposed. The method for manufacturing a multilayer wiring board according to claim 1 . The method for manufacturing a multilayer wiring board according to claim 3 or 4, wherein the wiring film forming metal layer and the wiring film forming metal thin plate of the first multilayer wiring board or the fourth basic wiring board are etched simultaneously. Obtaining a fifth basic wiring board by patterning the metal layer for forming a wiring film of the third basic wiring board by selective etching;
Laminating a metal thin film for forming a wiring film on the exposed top of the bump for connecting the upper and lower wirings of the first basic wiring board prepared separately to obtain a fourth basic wiring board;
Laminating the top of the upper and lower wiring connection bumps of the fifth basic wiring board opposite to the wiring film formed on the fourth basic wiring board ; and
To claim 1, characterized in that it comprises a step of laminating to face the third wiring layer that the apexes of the upper and lower wiring between contact bumps basic wiring board is formed in the fifth basic wiring substrate prepared separately The manufacturing method of the multilayer wiring board as described. 6. The multilayer metal plate according to claim 3 , wherein the etching stop layer contains nickel, and the bump forming metal layer, the wiring film forming metal layer, and the wiring film forming metal thin plate contain copper. A method for producing a multilayer wiring board according to claim 1.   The method of manufacturing a multilayer wiring board according to any one of claims 1 to 7, wherein a diameter of an area necessary for connecting the bumps for connecting the upper and lower wirings is 0.1 mm or less.

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