JPH03155189A - Manufacture of multilayer interconnection board - Google Patents

Abstract

PURPOSE:To improve heat resistance by forming a photo-sensitive resin layer at an inner-layer material and forming an outer-layer material into one piece through a resin layer. CONSTITUTION:A photo-sensitive resin layer is provided on each circuit-forming surface of a required number of inner-layer materials. Then, a resin layer other than a circuit part is cured and is allowed to reside and a resin layer on the circuit is eliminated. Then, an outer-layer material is provided in one piece on the upper surface and/or lower surface through a resin layer. The inner-layer material consists of an electrical circuit which is formed on a single-surface or a double-surface metal-clad laminated plate consisting of a resin such as a phenol resin, a cresol resin, an epoxy resin, and a fluoric resin, an inorganic fiber such as glass and asbestos, an organic synthetic fiber such as polyester, a natural fiber such as cotton, and paper base. A photo-sensitive dry film and a UV curing type varnish is used alone or together as a photo-sensitive resin. Individuals such as copper, aluminum, iron, nickel, and zinc or a metal foil consisting of an alloy or a single-side metal clad laminated plate is used as the outer-layer material.

Description

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

[Conventional technology]

In conventional multilayer wiring boards, circuits are still formed on the surface of the inner layer material, so a considerable amount of the resin layer interposed between the inner layer materials or between the inner layer materials and the outer layer materials is free from unevenness caused by the circuit parts. It was consumed to fill the recesses, and the heat resistance decreased due to insufficient amount of resin between the eyebrows.

As a countermeasure to this problem, if the total amount of resin in the resin layer interposed between the layers is increased, there is a problem in that slipping occurs during lamination molding.

[Problems that the invention attempts to solve]

As described in the conventional technology, heat resistance of multilayer wiring boards tends to decrease due to insufficient amount of interlayer resin, and when the amount of resin in the resin layer interposed between layers is increased, there is a problem of sliving. This method was developed in view of the above-mentioned problems, and its purpose is to provide a method for manufacturing a multilayer wiring board that does not cause slipping and is more heat resistant.

[Means for solving problems]

In the present invention, a photosensitive resin layer is provided on each circuit forming surface of a required number of inner layer materials, and the resin layer other than the circuit portion is left cured, and the resin layer on the circuit is removed and the upper and/or lower surface is covered with resin. Since the manufacturing method for multilayer wiring boards is characterized by integrating the outer layer material through layers, the surface of the inner layer material is smooth even after circuit formation, so the amount of resin interposed between the layers is wasted. The present invention will now be described in detail.

Inner layer materials used in the present invention include resins such as phenolic resin cresol resin, epoxy resin, unsaturated polyester resin, polyimide resin, polybutadiene resin, polyphenylene sulfide resin, polybutylene terephthalate resin, polyethylene terephthalate resin, and fluorinated resin, Electric circuits are formed on single-sided or double-sided metal-clad laminates made of inorganic fibers such as glass and asbestos, organic synthetic fibers such as polyester, polyacrylic, polyamide, and polyvinyl alcohol, natural Mi fibers such as cotton, paper, and base materials. This is what I did. As the photosensitive resin layer, photosensitive dry film, Uv
The curable varnish can be used alone or in combination, and there are no particular limitations.The photosensitive resin layer disposed on the circuit forming surface of the inner layer material leaves the resin layer other than the circuit portion cured, and the resin layer on the circuit is left cured. By removing it in an uncured state, an inner layer material with a smooth surface can be obtained. The resin layer interposed between the inner layer materials or between the inner layer material and the outer layer material may be a resin coating layer such as that used for the inner layer material, a resin sheet layer, or a resin-impregnated base material layer consisting of a resin and a base material, and may be used alone. Alternatively, it can be used in combination as a layer, but it is preferable to use the required number of resin-impregnated base materials to ensure thickness uniformity.As the b0 outer layer material, copper, aluminum, iron, nickel, zinc, etc. A single metal foil, an alloy, or a composite metal foil or a single-sided metal-clad laminate can be used. Integration methods include multi-stage press method, vacuum multi-stage Fres method, multi-roll method, tuple belt method, drum method,
Lamination is carried out using a pressureless continuous heating method or the like.

The present invention will be explained below based on examples.

Example After forming electric circuits on both sides of a double-sided copper-clad glass base epoxy resin laminate (copper foil thickness: 0.03510 g each) with thickness Q of 45 m+11, a UV-cured resin face (manufactured by Matsushita Electric Works Co., Ltd.) was applied to the circuit-forming surface. , Product number Banasealer CV 700
After screen printing 0), the resin layer other than the circuit part is left cured using a pattern, and the resin layer on the circuit is removed in an uncured state to obtain an inner layer material with a smooth surface. A laminate with two epoxy resin-impregnated glass cloth substrates each having a thickness of Q and l Mlll placed on the upper and lower sides and a copper foil having a thickness of Q and 035 fl+ as an outer layer material was formed at a pressure of 30 kg/, -j, tss. Lamination molding was performed at ℃ for 120 minutes to obtain a four-layer circuit wiring board.

Comparative Example Same as the example except that a 0.6-thick double-sided steel-clad glass base epoxy resin laminate (copper foil thickness 0.035 mm each) with electric circuits formed on both sides was used as the inner layer material. A four-layer circuit wiring board was obtained by processing in the same manner.

Table 1 shows the performance of the four-layer circuit wiring boards of Examples and Comparative Examples.

Note ※ 2 The cracker test was conducted at atmospheric pressure and 133°C for 40, 60, and 90 minutes, and then immersed in molten solder at 260°C for 30 seconds. Those with no blistering were considered to pass, and those with blistering were considered to be failed.

〔Effect of the invention〕

The present invention is constructed as described above. The multilayer wiring board obtained by the method for manufacturing a multilayer wiring board described in the claims has the effect of improving heat resistance.

Claims (1)

[Claims] (1) A photosensitive resin layer is provided on each circuit forming surface of the required number of inner layer materials, and the resin layer other than the circuit part is left cured, and the resin layer on the circuit is removed and the upper and/or lower surface is covered with resin. A method for manufacturing a multilayer wiring board, characterized in that outer layer materials are arranged and integrated through layers.