JP2001077499A - Complex wiring board and manufacture, wiring board used for the same and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high reliability wiring board which is adaptable to mounting of extremely highly integrated semiconductor devices. SOLUTION: A first wiring board 1 which is formed by providing both sides of a rigid insulating layer 2 with wiring layers 3 and 4 and a second wiring board 6 which is formed by providing both sides of a rigid insulating layer 7 with conductor plated wiring layers 8 and 9 are layered and integrated via an insulating layer 11. The wiring layer 4 of the first wiring board 1 and the wiring layer 8 of the second wiring board 6, which are opposed to each other are interlayer connected through conductive bumps 12, which are arranged in such a way that they penetrate the insulating layer 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite wiring board and a method for manufacturing the same, and further to a wiring board used therefor.

[0002] The present invention also relates to a semiconductor device such as a semiconductor package having a semiconductor element mounted on a composite wiring board.

[0003]

2. Description of the Related Art In recent years, semiconductor elements have been highly integrated, and, for example, devices having several hundred to several thousand connection terminals in a 10 mm square shape have appeared. For this reason, there is a demand for the development of a printed wiring board on which a semiconductor element having a large number of connection terminals arranged at such a fine pitch can be mounted.

As a printed wiring board on which high-density wiring and mounting are possible, what is called a build-up wiring board is known. That is, this build-up wiring board is formed by laminating one or more thin resin layers and conductor wiring layers in order on both sides of a core layer made of a rigid printed wiring board or the like, thereby forming a build-up layer. Since fine interlayer connections are formed in the resin layer by a photolithography technique or the like, much higher-density wiring design is possible than in a conventional through-hole substrate.

However, at the current technical level, the wiring width of the build-up wiring board is at least about 40 μm, and it is difficult to cope with the semiconductor element having several hundred to several thousand connection terminals described above.

On the other hand, a flexible substrate in which a wiring layer is formed on the surface of an insulating film made of polyimide or the like is also known as a printed wiring board on which fine wiring can be formed. Semiconductor packages in which a plurality of layers are stacked and a semiconductor element is mounted thereon are also being developed.

[0007] In such a flexible substrate, the surface of the insulating film is flat with almost no irregularities due to the influence of the wiring layer on the surface unlike a build-up substrate, so that finer wiring can be formed. It is.

However, in a substrate in which a plurality of flexible substrates each having a wiring layer formed on the surface of an insulating film are laminated, the difference in the coefficient of linear expansion between the constituent material of the insulating film and the motherboard on which the wiring substrate is mounted is different. Large (for example, the coefficient of linear expansion of polyimide is about 8 ppm at room temperature, whereas the coefficient of linear expansion of epoxy resin-impregnated glass cloth generally used as an insulating layer material of a motherboard is about 14 to 17 ppm at room temperature. Therefore, there is a problem that connection reliability is lacking.

Therefore, for example, a composite wiring board in which a flexible board capable of high-density wiring is laminated on a normal rigid wiring board has been studied.

However, when such different kinds of substrates are integrated, the following problems occur.

That is, generally, when a plurality of substrates are integrated, a method is used in which the substrates are superimposed via an adhesive insulating layer such as a prepreg and then heated and pressed integrally, but the substrate materials are different. Then, there is a problem that a difference occurs in the adhesive strength and one of the substrates is easily peeled off.

[0012]

As described above, as semiconductor devices become more highly integrated, semiconductor devices with a very high degree of integration, such as 10 mm square and having hundreds to thousands of connection terminals, are mounted. There is a need for a wiring board that can do this.

However, in a build-up wiring board known as a printed wiring board capable of high-density wiring, the minimum wiring width is about 40 μm, and it is difficult to cope with it. In addition, a flexible board in which a wiring layer is formed on the surface of an insulating film and a plurality of layers are laminated, although a sufficient wiring density can be obtained, but the connection reliability when mounted on the motherboard is lacking. There's a problem. In order to solve this problem, a combination of a flexible substrate capable of high-density wiring and an ordinary rigid wiring substrate has been studied, but there is a problem that one of the substrates is easily peeled off.

SUMMARY OF THE INVENTION The present invention has been made in order to address the problems of the prior art, and a composite wiring board on which a highly integrated semiconductor element can be mounted, a method of manufacturing the same, a wiring board used for the same, Still another object is to provide a highly reliable semiconductor device using such a composite wiring board.

[0015]

According to a first aspect of the present invention, there is provided a composite wiring board comprising a rigid insulating layer having wiring layers on both surfaces thereof.
Wiring board, a second wiring board comprising conductor plating wiring layers on both surfaces of a rigid insulating layer, and wiring of the first wiring board opposed to the first and second wiring boards sandwiched between the first and second wiring boards An insulating layer having an interlayer connecting portion for electrically connecting the layer and the wiring layer of the second wiring board is provided.

Here, the first wiring board may be a multilayer wiring board having a plurality of wiring layers and a plurality of insulating layers.

Further, the second wiring board may be a multilayer wiring board having a plurality of wiring layers and a plurality of insulating layers.

Further, the plurality of wiring layers of the first wiring board may be connected to each other by a conductive bump disposed so as to penetrate an insulating layer insulating the wiring layers.

Further, the plurality of wiring layers of the second wiring board may be connected to each other by conductive bumps provided on an insulating layer for insulating these wiring layers.

Further, the interlayer connection portion of the insulating layer sandwiched between the first and second wiring boards may be constituted by a conductive bump disposed so as to penetrate the insulating layer. .

The composite wiring board of the present invention is provided integrally with a wiring board having a wiring layer provided on both surfaces of a rigid insulating layer, and on one surface of the wiring layer via an insulating layer. A conductor plating wiring layer electrically connected to the one wiring layer is provided.

Here, the wiring board may be a multilayer wiring board having a plurality of wiring layers and a plurality of insulating layers.

The insulating layer interposed between the conductive plating wiring layer and the wiring board may be made of an anisotropic conductive material.

Further, the electrical connection between the wiring layer of the wiring board and the conductor plating wiring layer is made by a conductive bump disposed so as to penetrate the insulating layer for insulating these wiring layers. Is also good.

A semiconductor device according to the present invention includes the composite wiring board and at least one semiconductor element mounted on the composite wiring board.

Here, the semiconductor element may be mounted by flip-chip connection.

[0027] The wiring board of the present invention is characterized in that a conductor plating wiring layer is provided on both surfaces of a rigid insulating layer.

Here, the conductive plating wiring layers may be connected to each other by conductive bumps provided on the insulating layer for insulating these wiring layers.

According to the method of manufacturing a composite wiring board of the present invention, a conductive bump having a projecting shape is provided at a predetermined position on the one wiring layer of a first wiring board having a wiring layer on both surfaces of a rigid insulating layer. Forming, sequentially laminating a second wiring substrate comprising a conductive plating wiring layer on both surfaces of an insulating sheet and a rigid insulating layer on the conductive bump forming surface, and pressing the laminate. And bonding the conductive bumps to the opposing conductive plating wiring layer of the second wiring board by penetrating the tip of the conductive bump through the insulating sheet.

In the method for manufacturing a composite wiring board according to the present invention, a step of forming required first and second conductor plating patterns on the first and second supports, respectively, Forming a protruding conductive bump at a predetermined position; and forming the conductive bump on the second support having an insulating sheet and a conductive plating pattern formed on the conductive bump forming surface. A step of sequentially laminating the laminate toward a surface, and pressing and integrating the laminate, and joining a tip end of the conductive bump to the opposing conductor plating pattern of the second support by penetrating the insulating sheet. The method may further include the steps of: removing the first and second supports from the integrated laminate to produce the second wiring board.

[0031]

Embodiments of the present invention will be described below in detail.

FIG. 1 is a sectional view schematically showing one embodiment of the composite wiring board of the present invention.

In FIG. 1, reference numeral 1 denotes a rigid insulating layer 2
And wiring layers 3 and 4 formed by patterning a conductive metal foil such as a copper foil on both surfaces thereof, and a conductive layer that penetrates insulating layer 2 and electrically connects wiring layers 3 and 4 facing each other. 1 shows a first wiring board provided with bumps 5. 6 is
It has a rigid insulating layer 7, wiring layers 8 and 9 formed on both surfaces thereof by copper plating, and conductive bumps 10 penetrating the insulating layer 7 and electrically connecting the wiring layers 8 and 9 facing each other. 2 shows a second wiring board.

The first and second wiring boards 1 and 6 are laminated and integrated via an insulating layer 11 and are provided with conductive bumps provided so as to penetrate the insulating layer 11. The wiring layer 12 electrically connects the wiring layers 4 and 8 facing each other with the insulating layer 11 interposed therebetween.

The material for forming each of the insulating layers 2, 7, 11 may be a polycarbonate resin, a polysulfone resin, a thermoplastic polyimide resin,
Thermoplastic resin sheets such as fluorinated polyethylene resin, hexafluorinated polypropylene resin, and polyetheretherketone resin, and heat generated from semi-cured epoxy resin, bismaleimide triazine resin, polyimide resin, polyester resin, melamine resin, etc. Curable resin sheet,
Examples include sheets made of raw rubber such as butadiene rubber, butyl rubber, natural rubber, neoprene rubber, and silicone rubber. These sheets may contain an organic or inorganic insulating filler, or may be a composite sheet with glass cloth or glass mat, synthetic fiber cloth or synthetic fiber mat, or paper. Good. In the present invention, among others, a glass epoxy resin sheet or the like is placed on the insulating layer 2 of the first wiring board 1, a polyimide resin sheet is placed on the insulating layer 7 of the second wiring board 6, and further, they are interposed therebetween. It is preferable to use a polyimide resin sheet for the insulating layer 11 because the adhesive strength of each insulating layer is high.

The conductive bumps 5, 10, and 12 can be formed by selective metal plating or the like, but are easily formed by using a conductive composition such as a conductive paste. Examples of such a conductive composition include silver, gold, a body, platinum, nickel, tungsten, molybdenum, palladium, rhodium, a conductive powder such as solder powder, a polycarbonate resin, a polysulfone resin, a polyester resin, a phenoxy resin, and phenol. Examples thereof include those prepared by mixing a resin component such as a resin or a polyimide resin or a glass frit binder component. The conductive bumps 5, 1
The shapes of 0 and 12 are not limited to the inverted crown-shaped columnar shape as shown in the figure, but may be other shapes such as a conical shape or a spherical shape.

In the composite wiring board having the above structure, the first
The minimum diameter of the conductive bumps 5 of the wiring board 1 is about 200 μm, and the minimum wiring width / interval (Line / Space: L / S) is 1
The minimum diameter of the conductive bumps 10 of the second wiring board 6 is about 100 μm and the minimum L is about 100 μm / 100 μm.
/ S can be about 20 μm / 20 μm. Therefore, it is possible to sufficiently mount a semiconductor element having a very small arrangement pitch of the connection terminals.

In addition, since the rigid boards are joined to each other, sufficient joining strength between the insulating layers 4 and 11 of the first wiring board 1 and between the insulating layers 11 and the insulating layer 8 of the second wiring board 6 is obtained. Is obtained. Therefore, delamination unlike the case where the flexible substrate and the rigid substrate are combined does not occur.

In the composite wiring board of FIG. 1, the wiring board 1 in which the wiring layers 3 and 4 are formed on both surfaces of the rigid insulating layer 2 and the wiring layers 8 and 9 are formed on both surfaces of the rigid insulating layer 7. Wiring board 6 is separated from insulating layer 11 and conductive bump 12
However, the present invention is not limited thereto, and the wiring boards 1 and 6 to which the insulating layer 11 is connected may be configured to further include a multilayer wiring layer.

FIG. 2 schematically shows an example of a composite wiring board having such a multilayer wiring layer.

As shown in FIG. 2, this composite wiring board
The first wiring board 1 has four wiring layers 3, 4, 13, 14
And a multilayer wiring board having three insulating layers 2a, 2b and 2c.

The composite wiring board can be manufactured, for example, as follows.

That is, FIGS. 3 and 4 are views for explaining an example of a method of manufacturing the composite wiring board shown in FIG.

First, a projecting (columnar or conical) conductive bump 5 is formed on one main surface of the copper foil 15 by a method such as screen printing of a conductive paste. For example, an insulating adhesive sheet or prepreg 16 having a thickness of, for example, 50 μm is aligned and laminated on the surface on which the conductive bumps 5 are formed. After obtaining the laminated body, the same copper foil 17 as described above is aligned and laminated on an insulating adhesive sheet or prepreg 16 from which the tips of the conductive bumps 5 protrude. Then, the copper foils 15 and 17 of the double-sided copper-clad laminate are patterned by a photo-etching process or the like to form predetermined wiring layers 3 and 4 to obtain the first wiring board 1. (FIG. 3A) Next, at a predetermined position on the wiring layer 4 of the first wiring substrate 1,
Similarly to the above case, the conductive bumps 12 having a projection shape (columnar or conical shape) are formed by a method such as screen printing of a conductive paste. (FIG. 3 (b)).

The shape of the conductive bump can be formed into a desired shape by adjusting the pit diameter and thickness of a mask to be used, various physical properties such as a conductive paste to be used, the number of times of printing, and the like.

After the conductive bumps 12 are formed, the surface on which the conductive bumps 12 are formed is, for example, 50 μm thick (or 30 μm thick).
μm) of an insulating adhesive sheet or prepreg 18 is aligned and stacked, and heated and pressed to form a conductive bump 1.
An insulating layer 11 having a protruding tip is formed. (FIG. 3
(C)).

Further, the obtained laminate is sandwiched between press plates, and plastically deformed so that the heads of the conductive bumps 12 protruding from the insulating layer 11 are crushed (FIG. 3D).

On the other hand, a second wiring substrate 6 is manufactured separately.

First, for example, a 100 μm-thick stainless steel (S
After a resist film 22 having a thickness of about 20 μm is formed on the entire surface of a support 20 made of a US) plate, a pattern forming portion is opened by, for example, a photolithography method using a metal mask. A copper thin film 21 to be the wiring layer 8 is formed by plating (FIG. 4A). It is desirable that the thickness of the copper thin film 21 be substantially equal to that of the resist film 22.

Next, the resist film 22 is removed, and in this state, the projecting conductive bumps 10 are formed in a required area on the wiring layer 8 by a screen printing method using a metal mask or the like.
Is formed (FIG. 4B). Note that the conductive bumps 10 may be formed as they are without removing the resist film 22. In this case, since there is almost no step between the resist film 22 and the wiring layer 8, the printing of the conductive bumps 10 becomes easy, and the conductive bumps 10 with high dimensional accuracy can be formed. The resist film 22 is removed after the conductive bumps 10 are formed or after the supports 20 and 25 are peeled off. If only the portion where the conductive bumps 10 are to be formed has a desired size (for example, about 100 μm), the wiring layer 8 can be miniaturized to an L / S of about 20 μm / 20 μm.

Further, an insulating sheet 23 such as a prepreg having a thickness of, for example, 30 μm is laminated on the surface on which the projecting conductive bumps 10 are formed, and heated and pressed so that the tips of the conductive bumps 10 pass through the insulating sheet 23. (FIG. 4C).

Subsequently, the wiring layer 9 is formed on the surface of the laminated body where the end of the conductive bump 10 protrudes in the same manner as described above.
A support 25 made of, for example, a stainless steel (SUS) plate having a thickness of 100 μm is formed on the wiring layer 9 side by a conductive bump 10.
The layers are laminated and heated and pressed toward the formation surface side (FIG. 4D).
By this heating and pressurizing, the wiring layer 9 is embedded in the insulating sheet 23 and integrated, and the end of the conductive bump 10 contacts the wiring layer 9 to electrically connect desired wirings.

Thereafter, the supports 20 and 25 are peeled off to obtain the second wiring board 6 (FIG. 4E). Wiring layer 8,
Since 9 is formed by plating, the supports 20, 2
5 can be easily peeled off. Also, the support 20,
Since the surface after the peeling is flat and the space between the footprints is formed in a dam shape with an insulating material, there is an advantage in mounting a fine pitch component such as preventing a solder bridge at the time of mounting the component. As described above, the support 2
When the resist film 22 is removed after the 0 and 25 peeling, the resist film 22 may be heated and pressurized again thereafter, whereby the surface can be finished flat.

The second wiring board 6 can be manufactured by a method as shown in FIG.

That is, in the same manner as in the above case, the support 2 made of a stainless steel (SUS) plate having a thickness of, for example, 100 μm.
After the formation of the copper thin film 21 to be the wiring layer 8 on FIG.
(A)), a spherical conductive bump 26 is formed (FIG. 5).
(B)). The spherical conductive bumps 26 can be formed by a method such as printing or reflowing a conductive paste.

Next, a support 25 made of a stainless steel (SUS) plate on which a copper thin film 24 to be the wiring layer 9 is formed by electroplating on the surface on the side where the conductive bump 26 is formed The formation surface is laminated toward the conductive bump 26 formation surface side (FIG. 5C). Further, a frame mold 27 for injection molding is arranged between the laminated supports 20 and 25, and an insulating resin 28 used as a potting material is molded in the frame mold 27 (FIG. 5 ( d)).

Thereafter, the supports 20 and 25 are peeled off, and the frame 27 is opened, so that the structure shown in FIG.
A second wiring board 6 having a flat surface and electrically connecting desired wirings with the conductive bumps 26 is obtained. In the second wiring board 6 manufactured as described above, the wiring layers 8 and 9 have only a desired size (for example, 100 μm) where only the conductive bumps 10 are to be formed (joining portions).
), The L / S can be reduced to about 20 μm / 20 μm.

Then, the second wiring board 6 manufactured in this manner is aligned with the surface of the laminate of the first wiring board 1 and the insulating layer 11 on the insulating layer 11 side, and laminated and pressed. . Thus, a composite wiring board as shown in FIG. 1 is manufactured.

If necessary, after heating and pressurizing, solder resist processing, component masking processing, and surface finishing processing such as gold plating and solder coating may be performed.

The composite wiring board thus manufactured has a sufficient bonding strength of each layer, and has high reliability as a wiring board.

In the present invention, as shown in FIG. 6, an anisotropic conductive paste or an anisotropic conductive sheet is provided on the wiring layer 4 of the first wiring substrate 1 as described above. The wiring layer 29 formed by copper plating may be provided via the insulating layer 11 made of a conductive material.

In this case, the wiring layer 29 and the first wiring substrate 1
By making the distance between the wiring layers 4 substantially equal to the particle size of conductive particles such as metal powder contained in the anisotropic conductive material forming the insulating layer 11, desired electrical continuity between the wirings is obtained. be able to. FIG. 7 conceptually shows the electrical continuity between the wiring layers 29 and 4 made of such an anisotropic conductive material, and the symbol C is a conductive particle.

In order to manufacture the above wiring board, as shown in FIG. 8, on a support 30 made of, for example, a stainless steel (SUS) plate having a thickness of 100 μm, as in the case of the second wiring board 6, A pattern 31 of a copper thin film to be the wiring layer 29 is formed (FIG. 8A), and this is sandwiched on the first wiring board 1 manufactured by the method described above with an anisotropic conductive sheet 32 interposed therebetween. Is laminated with the pattern 31 forming surface side facing the first wiring substrate 1 and heated and pressed (FIG. 8B), or the wiring layer 4 is formed on the pattern 31 forming surface or the first wiring substrate 1.
An anisotropic conductive paste may be applied to the surface to be formed by a printing method or the like, and the layers may be similarly laminated and heated and pressed.

Although not shown, the wiring layer 4 of the first wiring board 1 is provided with an insulating layer 11 made of an anisotropic conductive material such as an anisotropic conductive paste or an anisotropic conductive sheet. Thus, the second wiring board 6 may be provided. First
The wiring layer 4 of the wiring board 1 and the wiring layer 8 of the second wiring board 6
Can be obtained by the conductive particles contained in the anisotropic conductive material.

In the present invention, the second wiring board 6
Alternatively, the copper plating wiring layer 29 does not need to be laminated on the entire surface of the first wiring substrate 1, but may be partially laminated only at a required position. The partially laminated structure is useful as a multi-chip module (MCM), a so-called multi-chip wiring board for a semiconductor package, or the like.

Hereinafter, the semiconductor device of the present invention will be described.

FIG. 9 is a diagram schematically showing a semiconductor package as an example of the semiconductor device of the present invention.

This semiconductor package is a BGA package in which a semiconductor element 41 is mounted on the composite wiring board 40 of the present invention shown in FIG. 1 by flip-chip connection. The semiconductor element 41 is a bare chip, and has a connection pad 42 provided on the semiconductor element 41 so as to be connected to an integrated circuit built in the semiconductor element.

The wiring layer 9 provided on the second wiring board 6 of the composite wiring board 40 is connected to the connection pads 42 of the semiconductor element 41.
And connection vias or via lands at positions opposed to. The semiconductor element 41 is flip-chip connected to the connection pad 42 by, for example, a conductive bump 43 formed of Pb / Sn solder or the like.
On the other hand, on the wiring layer 3 provided on the first wiring board 1 of the composite wiring board 40, solder balls 44 are provided so as to be arranged in a grid array.
Thereby, the semiconductor package is connected to an external circuit such as a motherboard. Incidentally, 45 is a solder resist.

In such a semiconductor package,
For example, connection pad diameter 150 μm, L / S is 5 μm / 5 μm
Semiconductor element, connection pad diameter 200μm, L / S is 20μm
/ 20μm fine rule wiring layer, connection pad diameter 500μ
m, L / S is 50μm / 50μm wiring layer, connection pad diameter 7
Like the mounting surface of 00 μm and L / S of 200 μm / 200 μm,
A semiconductor device in which wiring rules gradually become loose can be obtained.

FIG. 10A is a top view schematically showing another example of the semiconductor device of the present invention, and FIG.
FIG.

As shown in these figures, this device provides an insulating layer 11 on the entire surface of a first wiring board 1 of, for example, 300 mm to 500 mm square, and has fine design rules only in a region where a semiconductor element 41 is to be mounted. And a second wiring board 6 capable of being mounted on the second wiring board 6.
The semiconductor device 41 of mm □ is mounted by flip chip connection.

In such an apparatus, since the second wiring substrate 6 capable of fine design rules is selectively provided only in the area where the semiconductor element 41 is to be mounted, the semiconductor package shown in FIG. Can be manufactured.

FIG. 11A is a top view schematically showing still another example of the semiconductor device of the present invention.

This example is an example in which the semiconductor device of the present invention is applied to an MCM. For example, an insulating layer 11 is provided on the entire surface of a first wiring substrate 1 of 300 mm to 500 mm square, and a semiconductor in each MCM forming region is provided. The second wiring board 6 capable of fine design rules is provided only in the area where the element 41 is to be mounted. The semiconductor element 41 is mounted on the second wiring board 6 by flip-chip connection, and another chip component 4 such as a resistor or a capacitor is mounted on another required area.
6 is mounted. FIG. 11 (b) shows one MCM
FIG. 4 is an enlarged cross-sectional view of a formation region, and reference numeral 47 denotes a sealing resin.

In such an apparatus as well, the second wiring board 6, which allows fine design rules, is connected to the required semiconductor element 41.
Since it is selectively provided only in the mounting area, it is possible to manufacture at low cost an MCM on which a semiconductor element on which a large number of connection terminals are arranged at a fine pitch is mounted.

In each of the above examples, the semiconductor element 41 is mounted by flip chip connection, but other methods such as wire bonding may be used. In addition, a configuration in which the semiconductor element 41 is mounted on the wiring board as described in FIG. 6, that is, an anisotropic conductive paste such as an anisotropic conductive paste or an anisotropic conductive sheet is formed on the first wiring board 1. A configuration in which an insulating layer made of a material is provided, and a wiring layer formed by copper plating is formed thereon, and the semiconductor element 41 may be mounted. Further, in the examples shown in FIGS. 10 and 11, although there is a problem of bonding, a flexible substrate having a wiring layer formed on the surface of an insulating film may be used instead of the second wiring substrate 6. .

As described above, in the composite wiring board of the present invention, the conductive bumps 5 can cope with an interlayer connection with a fine pattern. Therefore, in the semiconductor package of the present invention, it is possible to mount a semiconductor element having a higher degree of integration and a higher density of arrangement of the connection pads 42.

[0079]

EXAMPLES Hereinafter, specific examples of the present invention will be described. However, it goes without saying that the present invention is not limited to such examples.

Example A metal screen having a hole having a diameter of 0.3 mm was aligned and placed on a copper foil having a thickness of 35 μm, and a conductive paste composed of silver powder and a phenol resin was printed and dried. This step was further repeated as necessary to form a conical conductive bump having a bottom surface diameter of 0.3 mm and a height of 0.3 mm.

Next, a glass epoxy prepreg having a thickness of 0.1 mm was aligned and laminated on the conductive bump forming surface of the copper foil, and heated and pressed so that the tip of the conductive bump penetrated the glass epoxy prepreg. Thus, a protruding laminate was obtained.

Further, a copper foil having a thickness of 35 μm was positioned and laminated on a glass epoxy prepreg from which the tips of the conductive bumps protruded, and heated and pressed to obtain a double-sided copper-clad laminate.

The copper foil on both sides of this double-sided copper-clad laminate was subjected to photoetching treatment and patterning to obtain a wiring board having a wiring layer (S / H = 50 μm / 50 μm) on both sides.

Subsequently, a conductive paste composed of silver powder and a phenol resin was screen-printed on the wiring board in the same manner as described above, so that the bottom surface was 0.2 mm in diameter and 0.2 mm in height.
After forming a conical conductive bump, a 0.1 mm thick glass epoxy prepreg is laminated and placed on the conductive bump formation surface, and heated and pressed to make the tip of the conductive bump glass A laminate protruding through the epoxy prepreg was obtained.

Separately from this, a wiring pattern was formed by forming a plating resist pattern on a support made of a stainless steel (SUS) plate having a thickness of 100 μm, and then applying a copper plating having a thickness of about 30 μm.

Next, on this copper plating pattern forming surface,
A conductive paste consisting of silver powder and a phenolic resin was screen-printed in the same manner as above, and the bottom diameter was 0.2 m
A conical conductive bump having a height of 0.2 mm and a height of 0.2 mm was formed.

Further, the thickness of the conductive bump formation surface is
A 0.1 mm glass epoxy prepreg was aligned and laminated, and heated and pressed to obtain a laminate in which the tips of the conductive bumps protruded through the glass epoxy prepreg.

A support made of a 100 μm-thick stainless steel (SUS) plate having a copper plating pattern having a thickness of about 20 μm formed on After forming and laminating with the forming surface facing the prepreg side, heating and pressurizing, the support is peeled off, and the wiring layers (S / H = 20
μm / 20 μm).

Thereafter, the wiring substrate was aligned and laminated on the glass epoxy prepreg surface from which the tips of the conductive bumps of the laminate protruded, and heated and pressed to produce a composite wiring substrate.

In the obtained composite wiring board, a semiconductor element having 900 full-grid connection pads at a pitch of about 0.35 mm could be mounted by flip-chip connection without delamination.

[0091]

As described above, according to the composite wiring board of the present invention, a semiconductor element having a high degree of integration and a high density of connection terminals can be mounted, and a small and thin semiconductor device can be provided. Obtainable.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing an example of a composite wiring board according to the present invention.

FIG. 2 is a sectional view schematically showing another example of the composite wiring board of the present invention.

FIG. 3 is a diagram for explaining an example of a method of manufacturing the composite wiring board shown in FIG.

FIG. 4 is a view for explaining a method of manufacturing an example of a wiring board used for the composite wiring board of the present invention.

FIG. 5 is a diagram illustrating a method of manufacturing another example of a wiring board used for the composite wiring board of the present invention.

FIG. 6 is a sectional view schematically showing still another example of the composite wiring board of the present invention.

FIG. 7 is a cross-sectional view conceptually showing electrical conduction between wiring layers made of an anisotropic conductive material.

FIG. 8 is a view for explaining an example of a method of manufacturing the composite wiring board shown in FIG. 6;

FIG. 9 is a view schematically showing an example of a semiconductor package of the present invention.

10A and 10B are diagrams schematically showing another example of the semiconductor device of the present invention, wherein FIG. 10A is a top view, and FIG. 10B is a cross-sectional view taken along the line BB.

FIGS. 11A and 11B are diagrams schematically showing still another example of the semiconductor device of the present invention, wherein FIG. 11A is a top view and FIG.

[Explanation of symbols]

1. First wiring board 2, 2a, 2b, 2c,
7, 11 insulating layer 1 insulating layer 3, 4, 13, 14 wiring layer 5, 10, 12, 26 conductive bump 8, 9, 29 copper plating wiring Layers 15, 17 ...
... Copper foil 16, 18, 23 ... Insulating sheet 20, 25,
30 Supports 21, 24, 31 Copper plating pattern 32
... conductive sheet 40 ... composite wiring board 41 ... semiconductor element

Continued on the front page (72) Inventor Noriaki Sekine 1 Toshiba-cho, Fuchu-shi, Tokyo Inside the Toshiba Fuchu Plant Co., Ltd. (72) Inventor Yoshitaka Fukuoka 1-Toshiba-cho, Fuchu-shi Tokyo Prefecture F-term in the Toshiba Fuchu Plant (reference) ) 5E317 AA24 BB01 BB02 BB03 BB12 BB13 BB14 BB15 BB16 BB17 BB18 BB24 BB25 CC22 CC25 CC31 CD11 CD15 CD18 CD21 CD25 CD32 CD34 GG03 GG14 5E346 AA02 AA06 AA12 AA43 CC02 CC03 CC38 CC38 CC32 CC38 CC38 EE31 FF01 FF18 FF22 GG02 GG06 GG09 GG15 GG17 GG19 GG28 HH25 HH26

Claims (10)

[Claims] A first wiring board having wiring layers on both surfaces of a rigid insulating layer; a second wiring board having conductor plating wiring layers on both surfaces of the rigid insulating layer; And the first wiring board sandwiched and opposed to the second wiring board.
A composite wiring board comprising: an insulating layer provided with an interlayer connecting portion for electrically connecting the wiring layer of the wiring board to the wiring layer of the second wiring board. 2. The method according to claim 1, wherein the plurality of wiring layers of the second wiring board include:
2. The composite wiring board according to claim 1, wherein the wiring layers are connected to each other by conductive bumps provided on an insulating layer insulating the wiring layers. 3. An interlayer connecting portion of the insulating layer sandwiched between the first and second wiring boards is made of a conductive bump disposed so as to penetrate the insulating layer. Item 3. The composite wiring board according to item 1 or 2. 4. The wiring width of the wiring layer of the first wiring board /
The distance between lines (line / space) is 50 μm / 50 μm or more, and the wiring width / interval (Line / Spa) of the wiring layer of the second wiring board is used.
4. The composite wiring board according to claim 1, wherein ce) is 30 μm / 30 μm or less. 5. A wiring board having a wiring layer provided on both surfaces of a rigid insulating layer, and one of the wiring layers is provided integrally on one surface of the wiring layer with an insulating layer interposed therebetween. A composite wiring board comprising a conductor plating wiring layer electrically connected. 6. The composite wiring board according to claim 5, wherein the insulating layer interposed between the conductive plating wiring layer and the wiring board is made of an anisotropic conductive material. 7. An electrical connection between the wiring layer of the wiring board and the conductive plating wiring layer is provided by a conductive bump disposed so as to penetrate the insulating layer that insulates the wiring layers. The composite wiring board according to claim 5, wherein 8. A semiconductor device, comprising: the composite wiring board according to claim 1; and at least one semiconductor element mounted on the composite wiring board. 9. A step of forming a protruding conductive bump at a predetermined position on said one wiring layer of a first wiring substrate having wiring layers on both surfaces of a rigid insulating layer; A step of sequentially laminating a second wiring board comprising a conductive plating wiring layer on both sides of an insulating sheet and a rigid insulating layer on a forming surface; And bonding the leading end of the second wiring board to the opposing conductor plating wiring layer of the second wiring board by penetrating the insulating sheet. 10. A step of forming required first and second conductor plating patterns on the first and second supports, respectively, and forming projecting conductive bumps at predetermined positions on the first pattern. Forming, and a step of sequentially laminating the second support having an insulating sheet and a conductive plating pattern formed on the conductive bump forming surface with the conductive plating pattern side facing the conductive bump forming surface, Pressurizing and integrating the laminate, joining the tip of the conductive bump through the insulating sheet to join the opposing conductor plating pattern of the second support, 10. The method for manufacturing a composite wiring board according to claim 9, further comprising the step of: peeling the first and second supports from the body to produce the second wiring board.