JP2005244107A - Method of manufacturing wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a wiring board which can prevent the overflowing of a back resin to the surface of a core substrate and thereby can form a laminate flat in manufacturing the wiring board, by a method wherein the core substrate is stored in the storage of a jig having the storage which is extended through from the surface to the backside of the jig, and has a size corresponding to the size of the core substrate, and then the back resin is attached to the backside to form the laminate on the surface. <P>SOLUTION: A first principal plane (surface) of the core substrate and a first principal plane (surface) of the jig are coated with an insulating material, and a heat curing material which constitutes a back insulation layer is attached to a second principal plane (backside) of the core substrate. The insulating material applied on the surfaces prevents the heat curing material attached between the second principal plane of the core substrate and the storage of the jig from overflowing from between the side faces of the jig and the core substrate to the surface. Thereafter, the laminate is formed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a wiring board.

  As a wiring board for fine arrangement, a build-up board has been developed in which a double-sided printed wiring board is used as a core layer, and thin insulating resin layers and conductor layers are alternately stacked thereon. This build-up method has become widespread for ease of design for fine patterning of conductor circuits and weight reduction.

  The printed wiring board is manufactured by forming a circuit on the surface of a metal foil-clad laminate. This laminated board is produced using a prepreg. A prepreg is generally obtained by impregnating a base material such as a glass cloth or an aramid fiber cloth with a synthetic resin such as an epoxy resin or a polyimide resin, followed by drying and semi-curing. The prepreg is a film body made of an organic resin and has a characteristic that when heated, the resin component becomes a viscous liquid and gradually cures with time. Therefore, this makes it possible to bond and integrate the substrate segments of the stacked layers.

  The multilayer wiring board is manufactured by laminating an outer layer metal foil such as a copper foil via a prepreg on an inner layer substrate on which an inner layer circuit is formed, and then heating and pressing the laminated body. It is often performed using.

  As a multilayer wiring board, the outer layer metal foil of the multilayer board is processed to form an outer layer circuit, a hole is formed in the insulating layer formed by curing the prepreg, and the via hole is plated. Some are manufactured by conducting the outer layer circuit and the inner layer circuit.

  A multilayer printed wiring board manufactured by the build-up method has a higher degree of freedom in wiring design than a conventional multilayer printed wiring board, but it is used as a high-performance printed wiring board taking advantage of this feature. Therefore, it is required to further reduce the thickness of the interlayer insulating layer and improve the flatness of the circuit pattern. The build-up multilayer wiring board is a double-sided multilayer board in which resin insulation layers are laminated on both sides of a ceramic or resin core board, or a single-area multilayer wiring board in which a resin insulation layer is laminated on one side of the core board. (Patent Document 1).

  In a method of manufacturing a wiring board that manufactures a plurality of wiring boards at once, there is a method of using a processing jig having a housing portion in which a plurality of core boards are arranged (Patent Document 2). In this method, a plurality of core substrates are prepared, and in order to prevent warping of the wiring substrate, the plurality of core substrates are accommodated in an accommodating portion of a processing jig to form a buildup layer. A housing portion for housing a plurality of core substrates is opened on the surface of the jig, and the depth of the housing portion is the same as the thickness of the core substrate. A plurality of core substrates are arranged in the processing jig housing portion so that the jig surface of the processing jig and the core surface of each core substrate are flush with each other. A first resin insulation layer is formed so as to cover each core surface.

JP 2001-36237 A JP 2003-133687 A

  Furthermore, there is a method of using two such jigs and bonding the back surfaces together with a back surface resin to efficiently form a build-up layer. However, there is a problem that the resin on the back surface protrudes from the space between the core substrate and the jig housing part and the build-up layer cannot be formed flatly, and also causes delamination. was there.

  Here, a conventional manufacturing method will be described with reference to FIG. FIG. 7A shows a cross-sectional view of a processing jig used in the manufacturing process of the wiring board. A core accommodating portion 101 is formed in the processing jig 100. The thickness of the processing jig 100 is the same as that of the core substrate 70 accommodated in the core accommodating portion 101. The processing jig 100 is made of a metal or a polymer material. The core substrate 70 for forming the wiring substrate accommodated in the core accommodating portion 101 is made of ceramic. A processing jig 100 and a processing jig 200 (the processing jig 200 is the same as the processing jig 100) are prepared, and as shown in FIG. The core substrate 70 is accommodated in the core substrate accommodating portions 101 and 201 of 100 and 200.

  As shown in FIG. 7B, a cross-sectional view when the core substrate 70 is accommodated in the processing jigs 100 and 200 is shown. The core substrate 70 is accommodated in the accommodating portions 101 and 201 of the processing jigs 100 and 200, the first main surface CP1 of each core substrate 70, the first main surface JP1 of the processing jigs 100 and 200, the core substrate. The second main surface CP2 of 70 and the second main surface JP2 of the processing jigs 100 and 200 are flush with each other. Then, in order to form an insulating resin layer in a form covering the second main surface JP2 of the first processing jig 100 and the second main surface CP2 of the core substrate 70, a resin 12 is attached, and a release sheet 13 is further formed. Adhere. Similarly, in order to form an insulating resin layer in a form covering the second main surface JP2 of the second processing jig 200 and the second main surface CP2 of the core substrate 70, the resin 12 is adhered, and the release sheet 13 is further formed. Adhere.

  7C, the second main surface JP2 of the first processing jig 100 and the second main surface JP2 of the second processing jig 200 are opposed to each other, so that the release sheet 13 Adhere these together. Thereafter, build-up layers are formed on the first main surface JP1 side of the first processing jig 100 and the first main surface JP1 side of the second processing jig 200, respectively. However, a gap 60 is generated between the processing jigs 100 and 200 and the core substrate accommodated in the accommodating portions 101 and 201, and the back surface resin flows out from the gap to the first main surface side. If a build-up layer is formed here, the build-up layer cannot be formed flatly due to the flow-out of the resin 61, causing delamination. Therefore, in order to prevent this, a process for removing the resin 61 that has flowed out is required, and the number of processes increases, leading to an increase in cost.

  Accordingly, an object of the present invention is to accommodate the core substrate in the jig housing portion, attach the back resin to the back surface, and form a build-up layer on the front surface, so that the back resin protrudes from the core substrate surface. It is an object of the present invention to provide a method for manufacturing a wiring board capable of preventing the occurrence of the problem and thereby forming a laminate in a flat manner.

Means for Solving the Problems and Effects of the Invention

The manufacturing method of the wiring board of the present invention for solving the above problems is as follows.
On the first main surface of the core substrate, a method for manufacturing a wiring substrate for forming a laminate having an insulating layer and a wiring layer,
The core substrate is accommodated in a jig having an accommodating portion corresponding to the size of the core substrate, penetrating between the first jig main surface and the second jig main surface,
In order to prevent the thermosetting material adhering between the second main surface of the core substrate and the housing portion of the jig from protruding from the gap between the jig and the side surface of the core substrate, Cover the first jig main surface with an insulating material,
A thermosetting polymer material that forms a back insulating layer is attached to the second main surface of the core substrate,
Form a build-up layer.

  The core substrate is accommodated in a jig having an accommodating portion having the same depth as the thickness of the core substrate, and the first main surface of the core substrate and the jig is covered with an insulating material. When an insulating material is used, it is easy to work and convenient. Thereby, by attaching the thermosetting material to the second main surface, the thermosetting material can be prevented from protruding from the gap between the core substrate on the first main surface side and the housing portion of the jig. . And a 1st buildup layer can be formed flatly and the reliability of the close_contact | adherence with a core board | substrate and a 1st buildup layer can be improved.

The second manufacturing method of the wiring board of the present invention is a manufacturing method of a wiring board that forms a laminate having an insulator layer and a wiring layer on the first main surface of the core substrate,
The core substrate is accommodated in a jig having an accommodating portion corresponding to the size of the core substrate, penetrating between the first jig main surface and the second jig main surface,
In order to prevent the thermosetting material adhering between the second main surface of the core substrate and the housing portion of the jig from protruding from the gap between the jig and the side surface of the core substrate, Cover the first jig main surface with an insulating material,
A thermosetting material that forms a back surface insulating layer is attached to the second main surface of the core substrate, and further a release sheet is attached,
The second jig main surfaces of the two jigs containing the core substrate are opposed to each other and bonded together.
A laminate is formed.

The core substrate is accommodated in the accommodating portions of the two jigs, and the second main surface sides are
By bonding, the subsequent steps can be performed efficiently. When the second jig main surface is opposed and bonded together, it is bonded with the back surface insulating layer and the release sheet interposed therebetween. In the same manner as described above, an insulating material is attached to the first main surface side (it is preferable to use a film-like material), and the thermosetting material protrudes from the jig and the first main surface side of the core substrate. Can be prevented. By sticking the insulating material to the first main surface to form the first buildup layer, the adhesion between the core substrate and the first buildup layer can be improved.

  A thermosetting resin is used as the insulating material. A first buildup layer can be formed by attaching a thermosetting resin to the first main surface and applying heat treatment. The insulating material is made of, for example, an epoxy resin and a silica filler. A film-like insulating material can be used. The film-like insulating material is easy to attach to the core substrate and forms a build-up layer by heat treatment, and is convenient from the viewpoint of adhesion to the core substrate.

  In the manufacturing process of the present invention, the thermosetting material for forming the back surface insulating layer attached to the second main surface of the core substrate and the insulating material attached to the first main surface of the core substrate are simultaneously thermoset. Can be processed. As a result, the process can be simplified and the manufacturing cost can be reduced.

  FIG. 1A is a cross-sectional view of a wiring board 1 manufactured according to the present invention, and FIG. The wiring substrate 1 is substantially plate-shaped, and the core substrate body 2 is composed of four ceramic layers. On the first main surface CP1 side of the core substrate 70, a first buildup layer 15 made of an epoxy resin or the like is formed, and a solder resist layer 29 made of an epoxy resin or the like is further formed. On the other hand, a back insulating layer 12 made of an epoxy resin or the like is formed on the second main surface CP2 side of the core substrate 70.

  A large number of substantially cylindrical through holes 5 penetrating the core substrate 70 are formed at predetermined positions, and through hole conductors 3 are formed therein. A buildup wiring layer 21 is formed between the buildup insulating layer 15 made of a polymer material and the solder resist layer 29 to form a laminate (buildup layer). In order to connect the core wiring layer 10 and the buildup wiring layer 21, a copper plated via conductor 16 is formed in the buildup insulating layer 15.

  Solder connection portions (solder bumps) for mounting electronic components on the wiring board 1 are formed at predetermined positions on the build-up wiring layer 21 so as to penetrate the solder resist layer 29 and protrude the first main surface 30 of the wiring board. ) 31 is formed. The solder bump 31 is made of a low melting point alloy such as Sn—Ag.

  Further, at a predetermined position of the core wiring layer 11 on the back surface side of the core substrate 70, that is, on the second main surface CP2 side, a back surface insulating layer (back surface resin layer) is formed by a composite material of inorganic fibers and a thermosetting polymer material. 12 is formed. Examples of the composite material include resins containing glass fiber or carbon fiber. That is, a prepreg can be used. For example, an epoxy resin can be used. At a predetermined position of the back surface insulating layer 12, an opening 14 that opens to the second main surface 32 is formed, and a part of the core wiring layer 11 is exposed. The core wiring layer 11 is coated with Ni and Au plating on its surface, and serves as a connection terminal to a printed board such as a mother board.

  FIG. 2A shows a cross-sectional view of the processing jig 100 used in the process of manufacturing the wiring board of the present invention, and FIG. The processing jig has a core housing portion 101 formed therein. In the present embodiment, four core housing parts 101 are formed, but the present invention is not limited to this. The thickness of the processing jig 100 is the same as that of the core substrate 70 accommodated in the core accommodating portion 101. The processing jig 100 is made of a metal or a polymer material, but it is desirable that the processing jig 100 be made of a polymer material particularly from the viewpoint of cost.

  In the present invention, the core substrate 70 for forming the wiring substrate accommodated in the core accommodating portion 101 is made of ceramic. When the core substrate 70 is manufactured, the ceramic is fired while forming a wiring using copper having a low electric resistance inside. However, if the treatment is performed at a high temperature, the wiring is melted.

  Next, the manufacturing process of the present invention will be described. As shown in FIG. 3A, the core substrate 70 is accommodated in the core substrate accommodating portion 101 of the processing jig 100. FIG. 3B shows a cross-sectional view when the core substrate 70 is accommodated in the processing jig 100. FIG. 3C is a plan view when four core substrates are accommodated in the four accommodating portions of the processing jig. The core substrate 70 is accommodated in the accommodating portion 101 of the processing jig 100, the first main surface CP1 of each core substrate 70, the first main surface JP1 of the processing jig 100, and the second main surface of the core substrate 70. CP2 and second main surface JP2 of processing jig 100 are flush with each other.

  As described above, the core substrate is accommodated in the accommodating portion of the processing jig, and two such processing jigs are prepared. As shown in FIG. 4A, first, a film-type thermosetting resin containing an inorganic filler in a form covering the first main surface JP1 of the first processing jig 100 and the first main surface CP1 of the core substrate 70. 15 (for example, made of epoxy and silica filler) is temporarily bonded. Similarly, the thermosetting resin film 15 is temporarily bonded so as to cover the first main surface CP1 of the second processing jig 200 and the first main surface CP1 of the core substrate 70.

  As shown in FIG. 4B, a resin is then used to form an insulating resin layer in a form covering the second main surface CP2 of the first processing jig 100 and the second main surface CP2 of the core substrate 70. 12 is adhered, and a release sheet 13 is further adhered. Similarly, in order to form an insulating resin layer in a form covering the second main surface JP2 of the second processing jig 200 and the second main surface CP2 of the core substrate 70, a resin 12 is attached, and a release sheet is further formed. 13 is attached.

  And as shown in FIG.4 (c), the 2nd main surface JP2 of the 1st processing jig | tool 100 and the 2nd main surface JP2 of the 2nd processing jig | tool 200 are made to oppose, and the release sheet 13 is provided. Adhere these together. Subsequently, the back insulating layer 13 and the thermosetting resin film to be the first buildup layer 15 are simultaneously heat-treated by vacuum hot pressing.

  FIG. 5 shows an enlarged view of the bonding process (FIG. 4) of the two processing jigs 100 and 200 accommodating the core substrate 70. As shown in FIG. 5A, the thermosetting resin film 15 for forming the first buildup layer is attached to the first main surfaces JP1 and CP1 of the first processing jig 100 and the core substrate 70. It is attached. A thermosetting resin 12 for forming a back surface insulating layer is attached to the second main surfaces JP2 and CP2 of the first processing jig 100 and the core substrate 70, and a release sheet 13 is further attached. . The thermosetting resin for forming the back surface insulating layer also flows into the gap 60 between the processing jig and the core substrate.

  The same applies to the second processing jig 200. The first main surface side JP2 of the first processing jig 100 and the second processing jig 200 are opposed to each other, and the release sheet 13 is sandwiched between them as shown in FIG. Thereafter, heat curing treatment is performed by vacuum hot pressing. A thermosetting resin film 15 for forming the first buildup layer is attached to the first main surface JP1 side of each of the first processing jig 100 and the second processing jig 200. Therefore, it is possible to prevent the thermosetting resin forming the back surface insulating layer from flowing out from the gap 60 between the processing jigs 100 and 200 and the core substrate 70 on the first main surface JP1 side.

  Subsequently, a buildup layer, a wiring layer, and a solder resist layer are formed on the first main surface to manufacture a wiring board. The process following FIG. 4 is shown in FIG. FIG. 6A is an enlarged view of FIG. 4C. In the substrate 70 of FIG. 4C, the through hole 5 and the core wiring layer 10 are already formed, and the first buildup is formed thereon. Layer 15 is formed. That is, as shown in FIG. 6A, the core substrate 70 is accommodated in the processing jigs 100 and 200, and the first buildup layer 15 is formed. Then, as shown in FIG. 6B, a copper-plated via conductor 16 is formed on the first buildup layer 15 on the first main surface of the core substrate, and a solder resist layer 29 is further formed. Subsequently, solder bumps 31 are formed so as to penetrate the solder resist layer 29 and protrude the first main surface 30.

  Thereafter, the first processing jig 100 and the second processing jig 200 are peeled off from the release sheet 13 to form an opening 14 at a predetermined position of the back surface insulating layer 12, whereby FIG. The wiring board 1 is completed.

  As described above, by temporarily adhering the first buildup layer to the jig surface in advance, there is no flow of the back resin to the first main surface. Further, since the pair of adhesion and the formation of the first buildup layer are performed at the same time, the process can be simplified. Cost can be reduced by simplifying the process. In addition, the reliability of adhesion between the core substrate and the buildup material can be improved.

Sectional drawing of the wiring board by the manufacturing process of this invention. Sectional drawing and top view of the jig | tool for a process used in the manufacturing process of this invention. The figure explaining the manufacturing process of this invention. The figure explaining the manufacturing process of this invention following FIG. The enlarged view of the manufacturing process in FIG. The figure explaining the manufacturing process of this invention following FIG. The figure explaining the conventional manufacturing process.

Explanation of symbols

1 Wiring board 13 Release sheet 15 Thermosetting resin film (first buildup layer)
70 Core substrate 100, 200 Processing jig 101, 201 Housing

Claims (4)

On the first main surface of the core substrate, a method for manufacturing a wiring substrate for forming a laminate having an insulating layer and a wiring layer,
The core substrate is accommodated in a jig having an accommodating portion corresponding to the size of the core substrate, penetrating between the first jig main surface and the second jig main surface,
In order to prevent the thermosetting material adhering between the second main surface of the core substrate and the housing portion of the jig from protruding from the gap between the jig and the side surface of the core substrate, One main surface and the first jig main surface are coated with an insulating material,
Adhering a thermosetting material forming a back insulating layer on the second main surface of the core substrate,
A method of manufacturing a wiring board, comprising forming a laminate. On the first main surface of the core substrate, a method for manufacturing a wiring substrate for forming a laminate having an insulating layer and a wiring layer,
The core substrate is accommodated in a jig having an accommodating portion corresponding to the size of the core substrate, penetrating between the first jig main surface and the second jig main surface,
In order to prevent the thermosetting material adhering between the second main surface of the core substrate and the housing portion of the jig from protruding from the gap between the jig and the side surface of the core substrate, One main surface and the first jig main surface are coated with an insulating material,
Adhering a thermosetting material for forming a back surface insulating layer on the second main surface of the core substrate, further attaching a release sheet,
The second jig main surfaces of the two jigs containing the core substrate are opposed to each other and bonded together,
A method of manufacturing a wiring board, comprising forming a laminate.   The method for manufacturing a wiring board according to claim 1, wherein the insulating material includes an epoxy resin and a silica filler.   The thermosetting material for forming a back surface insulating layer attached to the second main surface of the core substrate and the insulating material attached to the first main surface of the core substrate are simultaneously thermoset processed. Item 4. The method for manufacturing a wiring board according to any one of Items 1 to 3.

Images