JPH02215191A - Manufacture of multilayer wiring board - Google Patents

Abstract

PURPOSE:To improve an inner copper foil in adhesive strength by a method wherein copper bumps of specified size are provided to the inner copper foil through plating, a pattern is formed on the film, which is subjected to a black treatment, and an outer member is laminated on the inner copper foil through the intermediary of a resin impregnated base material in an integral structure. CONSTITUTION:A bump-like copper plating whose bumps are 1-4mum in size is provided to an inner copper foil through electroplating or the like, and a pattern is formed thereon, which is subjected to a black treatment and then formed into an integral structure with an outer member through the intermediary of a resin impregnated base material. If the copper bumps are smaller than 1mum in size, the inner copper foil is not improved in adhesive strength, and if larger than 4mum, the copper plating is easy to separate. A base material formed of woven fabric, non-woven fabric, paper, or the like of organic synthetic fiber or natural fiber is impregnated with phenol resin or the like and dried up to be used as a resin integrated base material. A metal foil or a one-side metal plated laminated board is used as an outer member. By this setup, an inner copper foil is improved in adhesive strength.

Description

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

[Conventional technology]

Conventionally, multilayer wiring boards used for electrical equipment, etc. are obtained by roughening the surface of inner layer copper foil by soft etching, blackening treatment, and then laminating and integrating it with outer layer material via a resin-impregnated base material. However, in the soft etching process, liquid management is not very important, and a reduction in the processing effect due to insufficient management is unavoidable.

[Problem that the invention seeks to solve]

As described in the prior art section, when the inner layer copper foil is subjected to soft etching treatment, processing variations are unavoidable. The present invention has been made in view of the above-mentioned problems in the conventional technology, and an object thereof is to provide a method for manufacturing a multilayer wiring board in which the adhesiveness of the inner layer copper foil is improved.

[Means for solving problems]

The present invention is a multilayer wiring characterized in that the inner layer copper foil is coated with cup-shaped copper plating of 1 to 4 microns, then patterned, and after blackening treatment, it is laminated and integrated with the outer layer material via a resin-impregnated base material. Due to the manufacturing method of the substrate, the cup-shaped copper plating has a set value effect and can improve the adhesive strength of the inner layer copper foil.The present invention will be described in detail below.

The thickness of the inner layer steel foil A used in the present invention is not particularly limited, but it is preferable to use a copper foil with a thickness of 18 to 105 microns. It is necessary to apply micron nob-shaped steel plating, form a pattern, and perform blackening treatment before use. That is, if the cup-shaped copper plating is less than 1 micron, the adhesive strength will not improve, and if it exceeds 4 microns, the plating will easily fall off. In addition, depending on the required number, degreasing treatment, pickling treatment, water washing treatment,
A drying process is applied to each. As the resin for the resin-impregnated base material, synthetic resins such as phenol resin, cresol resin, epoxy resin, unsaturated polyester resin, melamine resin, polyimide resin, polyphenylene oxide resin, and fluorinated resin are used, and the resin is mixed with glass, asbestos, etc. The amount of resin after drying is applied to base materials such as inorganic fibers, organic synthetic fibers such as polyester, polyamide, polyvinyl alcohol, polyurethane, and polyimide, and natural fibers such as cotton, woven fabrics, nonwoven fabrics, mats, nets, cheesecloth, and paper. A required number of resin-impregnated base materials having a thickness of 0.01 to Iff are interposed by impregnation and drying to a weight of 40 to 60 mm (hereinafter simply referred to as weight). As the outer layer material, a metal foil such as copper foil, aluminum foil, nickel foil, etc. or a single-sided metal-clad laminate is used. The lamination and integration means may be any lamination means such as a press, a ronol, a double belt, etc., and is not particularly limited.

The present invention will be explained below based on examples.

Example A double-sided steel-clad glass cloth base epoxy resin inner layer material with a thickness Q of 0.35g and a copper foil of 0.35g was electrolytically copper plated to form a cup-shaped copper plating of 2 microns and then patterned. After degreasing, pickling, and blackening, two epoxy resin-impregnated glass cloth substrates each having a resin content of 45 mm and a thickness of 0.1 fi are placed on the upper and lower sides of the treated inner layer material. 0,
A laminate with 031Sfi copper foil was molded under a molding pressure of 40
Kq/d, laminated for 90 minutes at 160°C and 4
A single circuit wiring board was obtained.

Comparative Example A four-layer circuit wiring board was obtained in the same manner as in the example except that the knob-like plating process in the example was replaced with a soft evetching process.

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

〔Effect of the invention〕

The present invention is constructed as described above. The method for manufacturing a multilayer wiring board having the structure described in the claims has the effect of improving the adhesive strength of the inner layer steel foil.

Claims (1)

[Claims] (1) Multilayer wiring characterized in that the inner layer copper foil is coated with cup-shaped copper plating of 1 to 4 microns, then patterned, and after blackening treatment, it is laminated and integrated with the outer layer material via a resin-impregnated base material. Substrate manufacturing method.