JPS6122681A - Metal foil laminated board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a metal foil-clad laminate used in a multilayer printed wiring board.

[W Kyoto Technology] Generally, metal foil-clad laminates used for multilayer printed wiring boards are manufactured by integrally laminating metal foils 2 on the front and back surfaces of an insulating layer 1, as shown in FIG. In order to improve the adhesion of the metal foil 2 to the insulating layer 1, both surfaces of the metal foil 2 are roughened by an electrical method or the like. however,
The roughness of the conventional metal foil 1 surface is approximately 10μ or more,
Therefore, although the adhesion can be improved, there is a disadvantage that the /1ull board thickness accuracy of the multilayer printed wiring board is reduced, and the metal foil 2 remains during etching, resulting in defects, and it is difficult to form fine patterns. there were.

[Object of the Invention] The present invention has been made in view of the above points, and it is an object of the present invention to improve the interlayer thickness accuracy of a multilayer printed wiring board, reduce defects during etching, and improve etching accuracy. The object of the present invention is to provide a metal foil-clad laminate that can be easily formed into a fine pattern.

L Presentation of the Invention J That is, in the metal foil clad laminate of the present invention, the surface of the metal foil 2 is roughened to a roughness of 5μ or less, and the roughened surface 3 of the metal foil 2 is placed on the insulating layer 1 side. It is characterized by laminating M2 on an insulating layer 1, and achieves the above object by setting the roughness of the metal foil 2 to 5μ or less.

The present invention will be explained in detail below. Copper foil can be used as the metal foil 2. The roughness of both the front and back surfaces of this metal foil 2 (
That is, as shown in FIG. 2, the difference between the peaks and valleys of the unevenness formed on the surface of the metal foil 2 is set to be 5μ or less, and the diameter of the copper flute treated foot is also set to be 5μ or less. This surface roughening method is not limited, but for example, metal! 2 can be subjected to electrolytic treatment to roughen the surface, or chemical treatment such as etching can be employed. Also, any of electrolytic copper foil, rolled copper foil, etc. can be used. The thickness of the metal foil 2 is also not limited. The metal foil 2 thus formed is laminated and integrated on both the front and back surfaces of the insulating layer 1 so that the roughened surface 3 faces the insulating Wi1 side (to obtain a metal foil-clad laminate. As the insulating layer 1 The insulating layer 1 is formed by impregnating and drying a resin such as epoxy resin or polyimide into a base material such as glass cloth or paper, and various insulating layers 1 can be used depending on the combination of the base material and resin.

Therefore, by laminating the metal M2 on the insulating layer 1, the roughness of the roughened surface 3 formed on the surface of the metal foil 2 is 5μ or less,
It is possible to improve the glabellar thickness accuracy of a multilayer printed wiring board, and to make the dielectric characteristics of the multilayer printed wiring board constant. Moreover, the signal propagation speed is stabilized. Further, since the surface roughness is small, residual copper defects during etching can be reduced, etching accuracy is improved, and fine patterns can be easily formed. The roughened surfaces 3.3 are formed on both sides of the metal foil 2 as shown in FIG. 2 to improve adhesion with the insulating layer 1 on the front and back surfaces when manufacturing a multilayer printed wiring board. There is.

The present invention will be specifically described below based on examples.

The front and back surfaces of the first raw copper foil are treated to a roughness of 3μ, and this copper foil is coated with polyimide ljf on glass cloth (2116 cloth, 4 ply).
III? (Kelimide 601 Rhone-Poulenc) was impregnated and dried on the front and back surfaces of the insulating layer, and heated to 200°C.
- A copper-clad laminate was obtained by laminating and integrating under the molding conditions of 6 hours and 45 kg/0 m2.

11. An insulating layer formed by treating the front and back surfaces of copper foil with a roughness of 1-2μ, and drying the copper foil by impregnating glass cloth (2116 cloth, 4-bray) with polyimide resin (Kelimide 601 Rhone-Poulenc). Loaded on the front and back sides of the
A copper-clad laminate was obtained by laminating and integrating under the molding conditions of 6 hours and 45 K Fl/0 m2.

Next, Table 1 shows the plate thickness accuracy, dielectric constant, and etching defect rate of the copper-clad laminates obtained in the conventional example and the example. From the results in Table 1, it was confirmed that the thickness tolerance of the multilayer printed wiring board, that is, the thickness accuracy, was improved, and it was also confirmed that the buffing of the dielectric constant was reduced, and the etching defect rate was reduced. Effect] As described above, in the present invention, since metal foil with a surface roughness of 5μ or less is laminated on the insulating layer, the glabellar thickness accuracy of the multilayer printed wiring board is improved, there are fewer defects during etching, and fine etching is achieved. This makes it easy to form a pattern.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of the same main part, and FIG. 3 is an explanatory diagram of a conventional example. 1 is an insulating layer, 2 is a metal foil, and 3 is a roughened surface. Agent Patent attorney Ishi 1) Chief 7 Figure 1 Procedural amendment (method) % formula % 2. Name of the invention lk Metallic foil clad laminate 3. Relationship with the person making the amendment Patent applicant address Kadoma, Osaka Prefecture City Oaza Kadoma 1048 address name (
583) Matsushita Electric Works Co., Ltd. Representative Iku Kobayashi 4, Agent 5, Date of amendment order October 9, 1980 6, Specification subject to amendment 7, Contents of amendment Engraving of the specification originally attached to the application As shown in the attached sheet (no change in content)

Claims (1)

[Claims] (1) A metal foil clad laminate, characterized in that the surface of the metal foil is roughened to a roughness of 5μ or less, and the metal foil is laminated on the insulating layer with the roughened surface of the metal foil facing the insulating layer. .