JPH03285394A - Manufacture of multilayer wiring board - Google Patents

Abstract

PURPOSE:To reduce the generation of blisters in inner layer circuits and perform efficient production by applying laminate molding processing to a required number of laminates wherein unclad plates are arranged on the upper and/or lower surfaces of inner layer members with semihardened resin layers. CONSTITUTION:Hardenable resin layers are provided on the surfaces and rears of a required number of inner layer members. After the resin layers have been semihardened, unclad plates are arranged on the upper and lower surfaces of the inner layer members with semihardened resin layers. A required number of laminates wherein metallic foil sheets with resin for an outer layer are arranged on outermost layers are sandwiched in between metal mold plates and laminate molding processing is applied to the laminates. The inner layer member is composed of a required number of prepregs which have a dried base material, such as woven cloth composed of inorganic fibers such glass fibers, organic synthetic resin fibers such as acrylic resin fibers or natural fibers such as cotton or paper, impregnated with a resin, such as fluororesin alone, its modified resin or mixture, are arranged with metallic foil sheets on the upper and/or lower surfaces of the prepregs and are integrated together. As the hardenable resin layer, the applied layer of thermosetting resin, such as phenol resin, hardenable resin, such as UV-hardenable resin, or an adhesive resin sheet is used. The unclad plate is composed of the prepregs alone which are used in the manufacture of a laminated sheet for electric use and integrally laminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a multilayer wiring board used in electrical and electronic equipment, computers, communication equipment, and the like.

[Conventional technology]

Conventional multilayer wiring boards consist of a laminate in which a required number of inner layer materials are sandwiched between inner plates, with metal foil for the outer layer arranged on the upper and/or lower surfaces of the inner layer material, and then multiple sets are stacked and stacked. Laminate molding is performed with the outside sandwiched between mold plates, but since there is an inner plate between the mold plates, the number of laminates interposed between the mold plates has to be reduced, which reduces productivity. There was a low drawback. However, if the inner plate is removed and multiple sets of laminates are sandwiched between mold plates and laminated, the circuit part of the inner layer material will float on the surface of the outer layer metal foil, making it unusable as a multilayer wiring board. do not have. For this reason, attempts have been made to suppress the floating of the inner layer circuit by using copper foil with an aluminum carrier as the metal foil for the outer layer, but this is not sufficient and requires an extra step of removing the aluminum. Attempts have also been made to perform laminated molding at low pressures, but there has been a problem in that the incidence of molding defects is high. [Problem to be solved by the invention] As mentioned in the conventional technology, in order to improve the productivity of multilayer wiring boards, it is not possible to use copper foil with an aluminum carrier as the metal foil for the outer layer or to perform lamination molding at low pressure. There are many shortcomings.

The present invention has been made in view of the above-mentioned problems in the conventional technology, and its purpose is to reduce the number of incomplete orders for inner layer circuits and to efficiently produce a multilayer wiring board. Our goal is to provide the following.

[Means for solving problems]

In the present invention, a curable resin layer is provided on the front and back surfaces of the required number of inner layer materials, and after semi-curing, an uncrowned board is arranged on the upper and/or lower surface of the inner layer material with the semi-cured resin layer, and the outermost layer is a resin-coated metal layer for the outer layer. This method of manufacturing a multilayer wiring board is characterized by sandwiching the required number of laminates with foil between mold plates and laminating them to obtain the required number of multilayer wiring boards. The present invention can be prevented from floating, and since no inner plate is used, the number of stacked bodies between the mold plates can be increased.The present invention will be described in detail below.

Inner layer materials used in the present invention include woven fabrics, nonwoven fabrics, mats, and paper made of vA@ fibers such as glass and asbestos, organic synthetic fibers such as polyester, polyamide, polyvinyl alcohol, and acrylic, and natural fibers such as cotton. Base material: phenolic resin, cresol m jm, epoxy resin, unsaturated polyester resin, melamine resin, polyimide, polybutadiene, polyamide, polyamideimide, polysulfone, polyphenylene sulfide, polyphenylene oxide, polybutylene terephthalate, polyether ether ketone, fluororesin An electrical laminate with an electric circuit formed on the metal foil of an electrical laminate made by integrally fixing the required number of prepregs impregnated with a resin, modified or mixed, etc., and metal foil arranged and fixed on the upper and/or lower surfaces of the required number of prepregs. It is. The curable resin layer may be a thermosetting resin such as a phenol resin, a cresol resin, an epoxy resin, an unsaturated polyester resin, a polyimide resin, a thermosetting polyphenylene oxide resin, or a UV curable resin. It is a coating layer, an adhesive resin sheet layer, etc., and preferably has a thickness of 0.025 to 0.1 mm after curing.

The curable resin layer is thermally cured (semi-cured (so-called B stage) by JV curing or a combination thereof to obtain an inner layer material with a semi-cured resin layer.As an unclad plate, electrical laminates are used. It is made by laminating and fixing only the prepreg used for manufacturing, and it may be the same as the prepreg used for the inner layer material, or it may be of a different type.As the resin-coated metal foil for the outer layer, copper, aluminum, etc. A resin layer containing the resin used for the above-mentioned curable resin layer as the main component is provided on one side of a single, alloy, or composite metal foil made of iron, nickel, zinc, etc., and the thickness of the resin layer is the same after drying. at 0.0 O5~O,I
Preferably, it is mm. Note that the thickness of the metal foil is 0.
018-0.07M is desirable. The mold plate may be made of iron, aluminum, copper, nickel, zinc, or the like alone, alloy, or composite mold plate, and the thickness is not particularly limited, but it is preferably 6 to 15 m+++. As for the lamination and integration means, a press, a multistage press, etc. are preferable, but are not particularly limited.

The present invention will be explained below based on examples.

(Example) Electric circuits are formed on both sides of a glass cloth base epoxy resin double-sided 70 micron thick copper clad laminate with a thickness of 0.5 mm.The inner layer material is formed with electric circuits on both sides so that the thickness will be 0.05 mm after curing. Epoxy resin (manufactured by Shell Chemical Co., Ltd., product number Epicoat 1)
001) After applying an epoxy resin face consisting of 100 parts by weight (hereinafter simply referred to as parts), 4 parts of dicyandiamide, 0.2 parts of hensyl dimethylamine, and 50 parts of methyloxytol, the mixture was heated at 150°C for 10 minutes. An inner layer material with a semi-hardened layer was obtained. Next, the resin layer side of the copper foil with a 0.018 mm thick epoxy resin layer was applied to the upper and lower surfaces of the inner layer material with a semi-hardened layer through one glass cloth base epoxy resin unclad laminate with a thickness of 0°2IIIll. Laminated body 30 arranged inside
The set was sandwiched between stainless steel mold plates having a thickness of 10 mm and laminated and molded at a molding pressure of 30 kg/cffl and 165'C for 120 minutes to obtain 30 multilayer wiring boards.

[Comparative Example I] The same inner layer material as in the example was coated with a 0.1 ++ thick epoxy resin-impregnated glass cloth prepreg on the upper and lower surfaces through two sheets of epoxy resin-impregnated glass cloth prepreg.
．． One set consisted of a laminate with 018mg of the same number placed between 2mm thick stainless steel inner plates, and 10 sets were sandwiched between 10ag thick stainless steel mold plates at a molding pressure of 30kg/C1a165. 120 at °C
Lamination molding was performed for minutes to obtain 10 multilayer wiring boards.

[Comparative Example 2] Thirty multilayer wiring boards were obtained in the same manner as in Comparative Example 1, except that 30 sets of the same laminates as in Comparative Example 1 were laminated as they were without using an inner plate.

[Comparative Example 3] The same laminate 30&II as in Comparative Example was laminated without using an inner plate, and the molding pressure was 10 kg/
Thirty multilayer wiring boards were obtained in the same manner as in Comparative Example 1 except that cIIi was used.

Table 1 shows the performance of the multilayer wiring boards of Examples and Comparative Examples 1 to 3.

The following is a blank table. [Effects of the Invention] The present invention is constructed as described above. In the method for manufacturing a multilayer wiring board described in the claims, there is less occurrence of floating of inner layer circuits, and there is an effect that productivity can be improved.

Claims (1)

[Claims] (1) A curable resin layer is provided on the front and back surfaces of the required number of inner layer materials, and after semi-curing, an unclad plate is placed on the upper and/or lower surface of the inner layer material with the semi-cured resin layer, and the outermost layer is the resin-coated metal for the outer layer. 1. A method for manufacturing a multilayer wiring board, comprising: sandwiching a required number of laminates on which foil is disposed between mold plates and laminating them to form a required number of multilayer wiring boards.