JPH09260840A - Multilayered printed wiring board manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method making it possible to easily produce a multilayered printed wiring board having electronic part housing holes with a conductor circuit exposed therein and through-holes at other than the housing holes, without damaging the exposed conductor circuit. SOLUTION: An adhesive and easily peelable resin layer 3 is formed on the surface of an intermediate board 2. Using this board, a multilayer board 11 is formed, which has electronic parts housing holes 10 with a conductor circuit exposed therein, through-holes are bored through this board 11, specified outer layer conductor circuit is formed on a metal foil 9, which is used to form a mask apart from the outer layer conductor circuit so that the periphery thereof locates at a position corresponding to a resin layer 3, and the mask is mechanically peeled from the board 11 to open the holes 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pin grid array (PG) for mounting electronic parts such as semiconductor chips.
A), a method of manufacturing a multilayer printed wiring board used for a device for mounting electronic components such as a ball grid array (BGA) and a chip carrier.

[0002]

2. Description of the Related Art In recent years, electronic parts such as semiconductor chips and chip parts have been reduced in size and weight. Along with this, the density of multilayer printed wiring boards for mounting electronic components has been increasing. In addition, as a substrate on which a semiconductor chip is mounted, a ceramic material with excellent thermal reliability has been conventionally used, but since it is possible to achieve high density and is superior in terms of signal speed, a resin material is used. Multilayer printed wiring boards using substrates have come into use.

A conventional method for manufacturing a multilayer printed wiring board for mounting a semiconductor chip is, for example, Japanese Patent Laid-Open No. 4 (1999) -264.
-369252 and Japanese Patent Publication No. 5-41039 are available. According to the method of Japanese Patent Laid-Open No. 4-369252, a plurality of substrates having wiring formed thereon are stacked while forming electronic component storage holes (recesses) to form a multi-layer board having stepped portions,
A method of manufacturing a multilayer printed wiring board by forming a through hole at any place other than the recess and plating the through hole, wherein after laminating the boards, a copper foil is adhered to the outermost side, and then the through hole is formed. Is formed, a plating film is formed on the surface and through holes, and then the plating film and the copper foil in the portion corresponding to the recess are removed by etching to form an open state. In the method disclosed in Japanese Patent Laid-Open No. 4-369252, when a conductor circuit is exposed in the electronic component housing hole, the conductor circuit in the electronic component housing hole is formed when the outermost conductor circuit is formed on the copper foil. There is a problem that it is damaged by the etching solution. In order to solve this problem, a method of protecting the conductor circuit in the electronic component housing hole with a material having resistance to an etching solution for etching the copper foil has been proposed, but in that case, the process is complicated. There was a new problem of becoming.

On the other hand, in the method disclosed in Japanese Patent Publication No. 5-41039, a board is arranged at the uppermost part, and a hole for an electronic component, which is covered with the board and has a conductor circuit exposed therein, is formed in a predetermined manner. After forming a multilayer board formed at the position, then forming a through hole, plating the through hole, then forming a conductor circuit on the surface of the substrate that is the outermost layer, and then the substrate that is located on the outermost layer Is a method of forming an opening for communicating the electronic component storage hole to the outside. In the method disclosed in Japanese Patent Publication No. 5-41039, since the conductor circuit protects the electronic component housing hole exposed inside by using the substrate, the electronic component housing hole is opened. However, since the substrate located in the outermost layer is cut using a router or the like, there is a problem that the conductive circuit in the electronic component storage hole is easily damaged by the cutting.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a predetermined electronic component housing hole in which a conductor circuit is exposed. A method for manufacturing a multilayer printed wiring board, wherein the conductor is exposed in the electronic component storage hole, which is formed in the position Without damaging the circuit
It is to provide a manufacturing method capable of easily manufacturing a multilayer printed wiring board.

[0006]

A method for manufacturing a multilayer printed wiring board according to the present invention comprises the following steps. (A) A bottom substrate having a conductor circuit, a metal foil, and an opening interposed between the metal foil and the metal foil, and having a frame-like adhesive property surrounding the opening. An easily peelable resin layer, an intermediate substrate formed on the surface on which the metal foil is laminated, and the resin layer is brought into contact with the metal foil,
A step of forming a multi-layer board which is pressure-bonded through an adhesive material and which is covered with a metal foil and has an electronic component housing hole in which a conductor circuit is exposed at a predetermined position; B) a step of forming a through hole in a portion other than the electronic component accommodating hole of the multilayer board and plating the through hole; (C) forming a predetermined outer layer conductor circuit on the metal foil;
A step of forming a mask which is separate from the outer conductor circuit and covers the electronic component housing hole made of a metal foil so that the outer periphery is located at a position corresponding to the resin layer; By peeling it off from the multilayer board,
The process of opening the electronic component storage hole.

According to a second aspect of the present invention, there is provided a method for manufacturing a multilayer printed wiring board, wherein in the step (A) of the method for manufacturing a multilayer printed wiring board according to the first aspect, the surface of the intermediate substrate where the resin layer is formed is formed. In addition, a copper foil layer having a shape corresponding to the resin layer and having a glossy surface is formed in advance, and the resin layer is formed on the copper foil layer.

A method for manufacturing a multilayer printed wiring board according to a third aspect of the present invention is the method for manufacturing a multilayer printed wiring board according to claim 1 or 2, wherein the resin has adhesiveness and is easily peelable. The layer is formed by using a solder resist.

A method for manufacturing a multilayer printed wiring board according to a fourth aspect of the present invention is the method for manufacturing a multilayer printed wiring board according to claim 1 or 2, wherein the resin has adhesiveness and is easily peelable. The layer is formed by using a peelable heat-resistant masking material containing a thermoplastic resin.

In the present invention, a frame-shaped resin layer having adhesiveness and easy peeling is formed on the surface of the intermediate substrate on the side on which the metal foil is laminated. Since the resin layer is brought into contact with the metal foil, a multilayer board is formed which is covered with the metal foil and has the electronic circuit housing hole in which the conductor circuit is exposed at a predetermined position. The adhesion strength between the frame-shaped resin layer and the metal foil is lower than the adhesion strength between the adhesive material and the metal foil. Therefore, in a later step, a mask covering the electronic component storage hole made of metal foil is formed so that the outer periphery of the outer conductor circuit is separated from the outer conductor circuit and the outer periphery is located at a position corresponding to the frame-shaped resin layer. The mask can be easily peeled off.

Further, in the invention of claim 2, in the step (A), the copper having a glossy surface, which has a shape corresponding to the resin layer in advance, is formed on the surface of the intermediate substrate where the resin layer is to be formed. When a foil layer is formed and a resin layer is formed on this copper foil layer, the adhesion strength between the resin layer and the glossy surface of the copper foil layer is
Since the adhesion strength is such that peeling can be easily performed, the mask that covers the electronic component storage hole made of metal foil can be easily peeled off.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings.

Step (A): As shown in FIG. 1A, a bottom substrate 1 having a conductor circuit 5, a metal foil 9 and an opening 6 interposed therebetween.
And an intermediate substrate having a frame-shaped resin layer 3 that surrounds the opening 6 and that has adhesiveness and is easily peelable on the surface on which the metal foil 9 is laminated. 2 and 2 are laminated with an adhesive material 7 in between so that the resin layer 3 is brought into contact with the metal foil 9. In the bottom substrate 1 in the embodiment shown in FIG. 1A, a conductor circuit 5 is formed on the inner layer side, and a metal foil 9 is attached on the outer surface side where the outer layer circuit is to be formed. . As the bottom substrate 1 and the intermediate substrate 2, those obtained by processing an epoxy resin glass cloth-based copper clad laminate, a polyimide resin glass cloth-based copper clad laminate, or the like can be used. Moreover, as the metal foil 9, a copper foil, an aluminum foil, a nickel foil, or the like can be used. As the adhesive material 7, for example, an epoxy resin film, a polyimide resin film, an epoxy resin glass cloth base material prepreg, a polyimide resin glass cloth base material prepreg, or the like is used. The intermediate substrate 2 has a frame-like resin layer 3 that surrounds the opening 6 and has adhesiveness and is easily peelable on the surface on which the single metal foil 9 is placed when laminated. Is formed.
The resin layer 3 in the present invention has a property of adhering the metal foil 9 when a multilayer board is formed, and the adhesive force with the metal foil 9 is greater than the adhesive force between the adhesive material 7 and the metal foil 9. A low-resin layer, specifically, a peeled heat-resistant masking material containing a solder resist printed and semi-cured or a thermoplastic resin (for example, # 503B manufactured by Asahi Chemical Laboratory Co., Ltd.).
-SH) can be formed by printing, heat treatment, or the like. The frame-shaped frame width referred to here is not particularly limited as long as it does not hinder the formation of the outer layer conductor circuit in the subsequent step. Further, the method of forming the resin layer 3 may be a printing method or the like and is not particularly limited.

As described above, after stacking, pressure bonding and as shown in FIG. 1 (b), the metal foil 9 is covered, and the conductor circuit 5 is exposed inside. Hole 10
The multi-layer board 11 in which is formed at a predetermined position is obtained. In the present invention, the adhesive material 7 can form the electronic component housing hole 10, and the position corresponding to the electronic component housing hole 10 and the portion where the resin layer 3 is arranged so that the resin layer 3 contacts the metal foil 9. Is open. In the embodiment shown in FIG. 1A, the conductor circuit 5 exposed inside the electronic component housing hole 10 is formed on the bottom substrate 1, but if necessary,
It may be formed on another substrate arranged between the bottom substrate 1 and the intermediate substrate 2.

Step (B) In this step, as shown in FIG. 2A, the through hole 4 is formed in a portion other than the electronic component accommodating hole 10 of the multilayer board 11 integrated by pressure bonding. . The method of forming the through hole 4 is not particularly limited, and the through hole 4 can be formed by drilling, for example. Then, the through hole 4 is plated to form a plated layer 12. The method of plating the through holes 4 is not particularly limited, and for example, a method of forming a plating layer 12 having a desired thickness by electroplating after performing thin plating by electroless plating, is used.
Can be formed in the through hole 4 and on the metal foils 9, 9 of the outer layer. In this way, as shown in FIG. 2B, a multi-layer plate 11 in which the plating layer 12 is formed in the through holes 4 and on the outer metal foils 9, 9 is obtained.

Step (C) In this step, the metal foils 9 and 9 are provided with a predetermined outer layer conductor circuit 13
And a mask 14 which is separated from the outer conductor circuit 13 and covers the electronic component housing hole 10 made of the metal foil 9 so that the outer periphery thereof is located at a position corresponding to the resin layer 3. To do. Here, the mask 14 made of the metal foil 9 means the mask 14 made of the metal foil 9 coated with the plating layer 12, as shown in FIG.
The method of forming the outer conductor circuit 13 and the mask 14 is not particularly limited, but it is preferable to perform the etching method from the viewpoint of mass productivity. When the etching method is used, it is necessary to protect the plated layer 12 in the through holes 4 by some method so that the plated layer 12 is not etched. For example, a dry film is used as an etching resist. A method such as covering the inside of the through hole 4 with a dry film for protection may be used. Further, the mask 14 is formed at a position where the outer periphery thereof corresponds to the resin layer 3. Therefore, when the outer layer conductor circuit 13 is formed, the etching liquid does not enter the electronic component housing hole 10, and the problem that the conductor circuit 5 in the electronic component housing hole 10 is damaged by the etching liquid does not occur.

Step (D) In this step, the mask 14 is mechanically peeled off from the multi-layer board 11 to open the electronic component storage hole 10 and then the step shown in FIG.
A multilayer board 11 in the state shown in is obtained. The method for peeling off the mask 14 is not particularly limited, and may be carried out manually or by using a device, but it is preferable to heat the resin layer 3 to which the mask 14 is adhered because peeling off becomes easier and easier. Further, as a method of using the apparatus, it is preferable to peel off the mask 14 while adsorbing the mask 14 under reduced pressure by an adsorbing apparatus because the peeling work can be efficiently performed.

In the present invention, the step (D) is completed as shown in FIG.
The multilayer board 11 in the state shown in (b) can be used as a final multilayer printed wiring board, and further, the conductor circuit 5, the outer layer conductor circuit 13 and the plated layer 12 in the through hole 4 are plated with nickel or gold. It can also be applied to obtain the final multilayer wiring board.

Next, another embodiment of the present invention will be described. In the step (A), as shown in FIG.
The bottom substrate 1 having the opening 6 and the conductor circuit 5, the two metal foils 9, the intermediate substrate 2 having the opening 6, and the adhesive material 7.
Prepare Then, a frame-shaped copper foil layer 8 having a glossy surface surrounding the opening 6 is formed on the surfaces of the bottom substrate 1 and the intermediate substrate 2 which are the outer layers when laminated. The formation of this copper foil layer 8 is planned to be formed on it in a later step.
It is formed in a shape corresponding to the resin layer 3 which has adhesiveness and is easily peelable. Then, the opening 6 is formed on the copper foil layer 8.
Forming a frame-shaped resin layer 3 having an adhesive property and being easily peeled off. Then, the materials thus produced are laminated as shown in FIG. 4 (a), and then pressure-bonded, and as shown in FIG. A multilayer board 11 is obtained in which the circuit 5 has an electronic component housing hole 10 exposed therein at a predetermined position. As described above, according to the present invention, the opening 6 is formed in the bottom substrate 1.
Can also be applied to the case where The following steps will be described by omitting the drawings.

Next, in the step (B), through holes are formed in the multi-layer board 11 which is pressure-bonded and integrated with each other except the electronic component housing holes 10, and the through holes are plated to form a plating layer. Form. Next, in the step (C), the metal foils 9, 9 on both surfaces are etched to form an outer layer conductor circuit, and the outer layer conductor circuit is separated from and independent of the outer layer conductor circuit, and the outer periphery thereof is formed at a position corresponding to the resin layer 3. Masks are formed on both sides of the multilayer board 11 to cover the electronic component storage holes 10 made of the metal foil 9 so that the parts are positioned. In addition, the metal foil 9,
A plated layer is present on the surface of the metal plate 9. When the etching method is used, it is necessary to protect the plated layer in the through holes by some method so as not to be etched, as in the case of the above-described embodiment. Next, in the step (D), the mask is mechanically peeled off from both surfaces of the multilayer board 11 to open the electronic component storage holes 10 from both surfaces. In the case of this embodiment, since the resin layer 3 is formed on the glossy surface of the copper foil layer 8, the resin layer 3 can be peeled off very easily. In this way, the multilayer board 11 in which the electronic component housing holes 10 are opened from both sides can be used as a final multilayer printed wiring board, and further, the conductor circuit 5, the outer layer conductor circuit and the through hole can be formed. It is also possible to apply nickel plating or gold plating to the inner plating layer to obtain the final multilayer printed wiring board. In this embodiment, since the bottom surface side of the electronic component housing hole 10 is also opened, another substrate such as a copper core to be a semiconductor mounting portion is attached to the obtained multilayer printed wiring board to improve thermal conductivity. It becomes possible to manufacture a semiconductor mounted device with improved performance.

[0021]

According to the method of manufacturing a multilayer printed wiring board of the present invention according to claims 1 to 4, a frame-like structure surrounding the opening is provided on the intermediate substrate, which has adhesiveness and is easily peelable. An electronic device in which a resin layer is formed on the surface where the metal foil is laminated, and the resin layer is brought into contact with the metal foil so that it is covered with the metal foil and the conductor circuit is exposed inside. Since the multilayer board having the component storage holes formed at predetermined positions is formed, the adhesion strength between the resin layer and the metal foil is lower than the adhesion strength between the adhesive material and the metal foil. Therefore, in a later step, a mask covering the electronic component storage hole made of metal foil is formed so that the outer periphery of the outer conductor circuit is separated from the outer conductor circuit and the outer periphery is located at a position corresponding to the frame-shaped resin layer. The mask can be easily peeled off. Therefore, according to the inventions according to claims 1 to 4, the conductor circuit has the electronic component housing hole exposed therein at a predetermined position,
It is possible to easily manufacture a multilayer printed wiring board in which plated through holes are formed in places other than the electronic component storage hole without damaging the exposed conductor circuit in the electronic component storage hole. become able to.

In the method for manufacturing a multilayer printed wiring board according to the second aspect of the present invention, a copper foil having a shape corresponding to the resin layer and having a glossy surface is formed on the surface of the intermediate substrate where the resin layer is to be formed. Since the layer is formed and the resin layer is formed on the copper foil layer, the adhesive strength between the resin layer and the glossy surface of the copper foil layer is such that the adhesive strength can be easily peeled off. Therefore, according to the invention of claim 2, the mask covering the electronic component housing hole made of the metal foil can be more easily peeled off, and in addition to the above effects, the manufacturing efficiency of the multilayer printed wiring board can be improved. Also plays.

[Brief description of drawings]

FIG. 1 is a cross-sectional view for explaining an embodiment of the present invention as a model.

FIG. 2 is a cross-sectional view for explaining, as a model, a step following that of FIG. 1 in one embodiment of the present invention.

FIG. 3 is a cross-sectional view for explaining, as a model, a step subsequent to FIG. 2 in one embodiment of the present invention.

FIG. 4 is a cross-sectional view for explaining another embodiment of the present invention as a model.

[Explanation of symbols]

 1 Bottom Substrate 2 Intermediate Substrate 3 Resin Layer 4 Through Hole 5 Conductor Circuit 6 Opening 7 Adhesive Material 8 Copper Foil Layer 9 Metal Foil 10 Electronic Component Storage Hole 11 Multilayer Plate 12 Plating Layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kaneko Daiji 1048, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd.

Claims (4)

[Claims] 1. A method of manufacturing a multilayer printed wiring board, comprising the following steps. (A) A bottom substrate having a conductor circuit, a metal foil, and an opening interposed between the metal foil and the metal foil, and having a frame-like adhesive property surrounding the opening. An easily peelable resin layer, an intermediate substrate formed on the surface on which the metal foil is laminated, and the resin layer is brought into contact with the metal foil,
A step of forming a multi-layer board which is pressure-bonded through an adhesive material and which is covered with a metal foil and has an electronic component housing hole in which a conductor circuit is exposed at a predetermined position; B) a step of forming a through hole in a portion other than the electronic component accommodating hole of the multilayer board and plating the through hole; (C) forming a predetermined outer layer conductor circuit on the metal foil;
A step of forming a mask which is separate from the outer conductor circuit and covers the electronic component housing hole made of a metal foil so that the outer periphery is located at a position corresponding to the resin layer; By peeling it off from the multilayer board,
The process of opening the electronic component storage hole. 2. In the step (A), a copper foil layer having a shape corresponding to the resin layer and having a glossy surface is previously formed on the surface of the intermediate substrate where the resin layer is to be formed, The method for producing a multilayer printed wiring board according to claim 1, wherein a resin layer is formed on the copper foil layer. 3. The production of a multilayer printed wiring board according to claim 1, wherein the resin layer having adhesiveness and easy peeling property is formed by using a solder resist. Method. 4. The peelable heat-resistant masking material containing a thermoplastic resin is used to form a resin layer which has adhesiveness and is easily peelable. 2. The method for manufacturing a multilayer printed wiring board according to 2.