JP2009206425A - Method of manufacturing multilayer substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method which suppresses dent caused by contamination during a process for the adhesion of a laminated multilayer substrate by of lamination press and prevents the breakage of a multilayer substrate caused by improper handling, in a method of manufacturing a multilayer substrate in which copper foil is laminated on each of both sides of an inner layer core through a prepreg by overlaying a plurality of pairs of a prepreg and copper foil and lamination-pressing the pairs. <P>SOLUTION: In a method of manufacturing a multilayer substrate in which a pair of a prepreg and copper foil is formed by overlaying the prepreg and the copper foil on each side of an inner layer, and a plurality of the pairs are lamination-pressed together, a method of manufacturing a multilayer substrate in which, instead of overlaying the lower copper foil, adhered, laminated bodies having copper foil up and a support sheet plate down which is wholly or partially adhered to the copper foil are overlaid, and after lamination press, the support sheet plate is separated, is provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a multilayer substrate by a laminating press.

Conventionally, in the production of multi-layer substrates, the multi-layer substrate lamination and bonding process consists of a set of copper foils laminated on both sides of the inner layer core via prepreg, with a stainless steel mirror plate in between. In general, a plurality of sets are stacked and laminated and pressed by heating and pressing for a certain period of time with upper and lower laminated press hot plates.
By the way, since the mirror plate is repeatedly used, foreign matters are more likely to adhere to the surface from the back surface. Therefore, when laminating and pressing, the copper foil surface on the side in contact with the surface of the mirror plate, that is, the lower side of the inner layer core is used. Scratches are likely to occur on the copper foil surface.
As a countermeasure for this, Patent Document 1 describes that a laminated body in which copper foil is bonded to both surfaces of a metal sheet plate via an adhesive is provided instead of the overlapping portion of copper foil / mirror plate / copper foil. Has been.
JP 2001-88244 A

  However, in patent document 1, since the laminated body which bonded copper foil on both surfaces of the metal sheet plate is used, the separation between the bonded copper foil and the metal sheet plate performed after the lamination press is not easy. That is, in patent document 1, since the laminated body which bonded the copper foil on both surfaces of the metal sheet board is used, after the lamination press, the several laminated | stacked whole group is integrated. For this reason, if it is going to separate for every group, it will be the work which peels off a multilayer substrate one by one, and will be in the state which flips up a multilayer substrate one by one, and the force which is going to bend acts on a multilayer substrate. For this reason, the multi-layer substrate is easily damaged, and particularly when the multi-layer substrate is a thin plate substrate, the multi-layer substrate is easily broken and becomes a problem.

The present invention solves the above-described problem, and suppresses dents due to the adhesion of foreign matters generated during the multi-layer bonding process of the multi-layer substrate by a multi-layer press, and prevents the multi-layer substrate from being broken by handling. It is a point to provide.

The present invention relates to the following.
(1) In the manufacturing method of a multilayer substrate in which a plurality of sets are stacked and pressed together, with a configuration in which a prepreg and a copper foil are stacked in that order on each of both surfaces of the inner layer core, the lower side of each set Instead of the copper foil, a multilayer substrate in which the copper foil is the upper side, and the adhesive laminate is laminated with the copper sheet and the support sheet plate bonded to the entire surface or a part of the lower side, and the support sheet plate is separated after the lamination press The manufacturing method of this is provided.
(2) In the above (1), a method for manufacturing a multilayer board in which a mirror plate is provided between the sets is provided.

According to the present invention, the cause of adhesion of foreign matters is eliminated, and the laminated body is easily separated, thereby suppressing dents due to the adhesion of foreign matters that occur in the multilayer bonding process of the multilayer substrate by the lamination press, and The manufacturing method which prevents the breakage of the multilayer substrate due to handling can be provided.

  As the inner layer core of the present invention, those generally used as a general inner layer of a wiring board can be used. For example, a metal foil made of a simple substance such as copper, aluminum, brass, nickel, iron, etc., an alloy or a composite foil is laminated and integrated on the upper surface and / or the lower surface of the required number of resin-impregnated substrates obtained by impregnating a resin composition with a reinforcing substrate. Then, a circuit is formed by etching or the like of the metal foil.

The prepreg described in the present invention is an adhesive sheet in which a reinforcing base material is impregnated with a resin composition to form a semi-cured B-stage, and a prepreg used for a general wiring board can be used.
As said resin composition, the well-known and usual resin composition used as an insulating material of a printed wiring board can be used. Usually, a thermosetting resin having good heat resistance and chemical resistance is used as a base, and one kind of resin such as phenol resin, epoxy resin, polyimide resin, unsaturated polyester resin, polyphenylene oxide resin, fluorine resin or the like Two or more types are used in combination, and as required, inorganic powder fillers such as talc, clay, silica, alumina, calcium carbonate, aluminum hydroxide, antimony trioxide, antimony pentoxide, glass fiber, asbestos fiber, pulp fiber Further, a fiber filler such as synthetic fiber or ceramic fiber is added.
In addition, the resin composition may be blended with a thermoplastic resin in consideration of dielectric properties, impact resistance, film processability, and the like. Further, various additives and fillers such as an organic solvent, a flame retardant, a curing agent, a curing accelerator, thermoplastic particles, a colorant, an ultraviolet light impermeant, an antioxidant and a reducing agent are added as necessary.
Examples of the reinforcing substrate include inorganic fibers such as glass and asbestos, polyester, polyamide, polyacryl, polyvinyl alcohol, polyimide, organic fibers such as fluorine resin, natural fibers such as cotton, nonwoven fabric, paper, mats, etc. Is used.
Usually, after impregnating or coating the reinforcing base so that the amount of the resin composition attached to the reinforcing base is 20 to 90% by weight in terms of the resin content of the prepreg after drying, the temperature is usually 100 to 200 ° C. And dried for 1 to 30 minutes to obtain a prepreg in a semi-cured state (B stage state). Usually, 1 to 20 sheets of this prepreg are stacked and heated and pressed in a configuration in which metal foils are arranged on both surfaces. As a molding condition, a method of a normal laminated plate can be applied. For example, a multi-stage press, a multi-stage vacuum press, continuous molding, an autoclave molding machine or the like is used, and a temperature is typically 100 to 250 ° C., a pressure is ^{2 to} 100 kg / cm ² , and heating is performed. The molding may be performed in the range of 0.1 to 5 hours, or may be performed under reduced pressure or atmospheric pressure under a lamination condition of 50 to 150 ° C. and 0.1 to 5 MPa using a vacuum laminating apparatus or the like. Although the thickness of the prepreg layer used as an insulating layer changes with uses, the thickness of 0.01-5.0 mm can be used normally.

The copper foil of this invention can use the metal foil used for a general wiring board. As for the surface roughness of the metal foil used in the present invention, the 10-point average roughness (Rz) shown in JISB0601 is preferably 2.0 μm or less on both surfaces in terms of electrical characteristics. Although copper foil, nickel foil, aluminum foil, etc. can be used for metal foil, copper foil is usually used. The production conditions of the copper foil are, for example, in the case of a plated copper foil using a copper sulfate bath, sulfuric acid 50-100 g / L, copper 30-100 g / L, liquid temperature 20 ° C.-80 ° C., current density 0.5-100 A / The condition of dm ² is generally used. In the case of plated copper foil using a copper pyrophosphate bath, conditions of potassium pyrophosphate 100-700 g / L, copper 10-50 g / L, liquid temperature 30 ° C.-60 ° C., pH 8-12, current density 1-10 A / dm ² Is commonly used. Whichever plating bath is used, various additives may be added in consideration of the physical properties and smoothness of copper.

  In the lamination press described in the present invention, a wiring board is manufactured by curing a resin in a prepreg by pressurizing and heating, with a structure in which a prepreg and a copper foil are stacked in that order on both surfaces of an inner core. Refers to the general process. The pressurizing and heating conditions are 150 to 220 ° C. and about 1 to 10 MPa.

The bonded laminate described in the present invention has a support sheet plate that is bonded entirely or partially on one side of a copper foil. It is assumed that foreign matter or the like is not mixed between the copper foil and the support sheet plate adhered thereto, and that the copper foil and the support sheet plate are easily peeled off from the end portions and are not left on the copper foil surface.
As the copper foil of the adhesive laminate, a general one similar to the above copper foil can be used.
The support sheet plate is a sheet plate that is bonded entirely or partially on one side of the copper foil. In addition to reinforcing the copper foil, the bending strength is preferably low. Specifically, it is a metal sheet plate of aluminum, tin, zinc, copper or the like, and the thickness is selected from 10 μm to 80 μm, preferably from 20 μm to 50 μm, depending on the purpose. When laminating without providing a mirror plate, the thicker one is preferable. The adhesive for bonding the copper foil and the support sheet plate is preferably easily peeled off from the interface of the adhesive after lamination without leaving the adhesive on the copper foil side, and the adhesive is provided on the entire surface, the edge, or in a spot shape. As the material, for example, an epoxy type, polyester type, polyimide type adhesive or the like is used.

The mirror plate described in the present invention is a generally used stainless steel plate having a thickness of about 1 mm to 3 mm and having a mirror surface. The mirror plate is used many times, and if the surface becomes rough, it is polished.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 shows a method for producing a multilayer substrate in the lamination press of the present invention. Fig.1 (a) has shown 1 set of press laminated bodies, and FIG.1 (b) has shown the press state of the several press laminated body.

  FIG. 1A shows a support sheet in which a copper foil 3 is laminated on both sides of an inner core 1 via a prepreg 2 and a copper foil 3 is laminated on the lower surface side, and the copper foil 3 is adhered to the entire surface or a part thereof. A set of press laminates in which the plate 4 is an adhesive laminate 5 is shown.

  FIG. 1B shows a state in which a plurality of sets of the press laminates 6 shown in FIG. 1A are stacked and the upper and lower ends are sandwiched between the press hot plates 7, and then the lamination press is performed. A cushioning material 8 is provided on the inside of the press hot plate 7 and a mirror plate 9 is provided on the inside thereof.

  Next, after the lamination press is finished, the stacked individual groups are separated, and as shown in FIG. 1 (c), (one set of pressed laminates 6 is shown upside down from FIG. 1 (a). .) The copper foil 3 side of a set of press laminates 6 is fixed to the fixing plate 10 while being sucked, and the support sheet plate 4 is separated from the end portion while being deformed upward.

As shown in FIG. 1, in a method for manufacturing a multilayer board in which a plurality of sets are stacked and pressed, each set of a prepreg and a copper foil stacked on each side of the inner layer core 1 in that order. When the laminated body 5 with the copper foil 3 as the upper side and the support sheet plate 4 bonded to the entire surface or a part of the copper foil 3 as the lower side is laminated and pressed instead of the lower copper foil 3, repeated use Therefore, there is no mirror surface plate on which the foreign matter is likely to adhere, and the lower copper foil 3 and the support sheet plate 4 are sealed with an adhesive, so that no foreign matter adheres between them. When pressed, no dent is generated in the lower copper foil 3. Further, the separation between the bonded lower copper foil 3 and the support sheet plate 4 has only the copper foil 3 on one side of the support sheet plate 4 and can be separated while folding the support sheet plate 4. There is no worry that will break.

FIG. 2 shows another method for manufacturing a multilayer substrate in the lamination press according to the present invention. The press laminated body 6 of FIG. 1A is made into one set, a plurality of sets are stacked, the upper and lower sides are sandwiched between press hot plates 7, and a mirror plate 9 is provided between the sets to perform the lamination press.

As shown in FIG. 2, in the method of manufacturing a multilayer board in which the prepreg and the copper foil are stacked in that order on each of both surfaces of the inner layer core 1 as a set, and the plurality of sets are stacked and pressed, In place of the lower copper foil 3, the adhesive laminate 5 with the copper foil 3 as the upper side and the support sheet plate 4 bonded to the entire surface or a part of the copper foil as the lower side is stacked, When the mirror plate is provided and laminated and pressed, it is the support sheet plate 4 that is in contact with the upper surface of the mirror plate 9 to which foreign substances are likely to adhere, so that the surface of the copper foil 3 on the support sheet plate 4 side of the multilayer substrate body In addition to the occurrence of dents on the edge of the foreign machine, the mirror plate 9 is provided for each group, so that the copper foils 3 on both sides are laminated with the inner core 1 sandwiched uniformly inside thereof, Even if the sets are stacked and stacked and pressed, the copper foils 3 on both sides of each set are similarly uniformly distributed. It is layered on the inner core layer 1 sandwiched therein.

Hereinafter, the present invention will be described based on examples.
First, a copper clad laminate having a copper foil on both sides (manufactured by Hitachi Chemical Co., Ltd., MCL-E-67, thickness 0.2 mm, copper foil thickness 12 μm) is used to form a circuit by etching the copper foil, An inner layer core having a length of 500 mm and a width of 500 mm was produced. Via a prepreg with a thickness of 40 μm on both sides of the inner core (manufactured by Hitachi Chemical Co., Ltd., GEA-67N), a copper foil with a thickness of 5 μm is supported on the upper surface and a copper foil with a thickness of 5 μm is supported on the lower surface side. As a sheet plate, a set of 50 μm thick aluminum plates bonded with a weak adhesive type two-component epoxy adhesive, and a set of 10 layers, 2 mm thick mirror plates on both upper and lower sides A cushioning material having a thickness of 200 μm was provided and pressed at a pressure of 3 MPa and a temperature of 180 ° C.
At this time, the average number of dent defects on the surface of the copper foil was 0.8 places / panel on the upper surface side and 0.1 places / panel on the lower surface side.

  Next, in the same manner as in Example 1, a pair of stacked sheets was provided with a mirror plate having a thickness of 2 mm, and the rest was pressed in the same manner as in Example 1. At this time, the average number of dent defects on the surface of the copper foil was 0.7 on the upper surface side / panel and 0.1 on the lower surface side / panel.

(Conventional example 1)
Prepare the same inner layer core as in Example 1, with 40 μm thick prepreg on both sides, 5 μm thick copper foil on the top and bottom, 1 pair, 2 mm thick mirror plate between, Pressing was performed in the same manner as in Example 1. At this time, the average number of dent defects on the surface of the copper foil was 0.8 places / panel on the upper surface side and 10.2 places / panel on the lower surface side.

The manufacturing method of the multilayer substrate in the lamination press of the present invention is shown. The manufacturing method of another multilayer substrate in the lamination press of the present invention is shown.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Inner layer core, 2 ... Prepreg, 3 ... Copper foil, 4 ... Support sheet board, 5 ... Adhesive laminated body, 6 ... Press laminated body, 7 ... Press hot plate, 8 ... Cushion material, 9 ... Mirror surface board, 10 ... Fixed plate.

Claims (2)

  In the method of manufacturing a multilayer board, in which a prepreg and a copper foil are laminated on each of both surfaces of the inner layer core in that order as one set, and the plurality of sets are stacked and pressed, the lower copper foil of each set A method for producing a multilayer substrate in which a copper foil is placed on the upper side, an adhesive laminate is laminated on the lower side of the copper foil and a support sheet plate that is entirely or partially bonded, and the support sheet plate is separated after laminating press .   2. The method for manufacturing a multilayer substrate according to claim 1, wherein a mirror plate is provided between the set.

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