JP2000077826A - Manufacture of circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the formation of damage and the like on the wiring pattern even in the case of the minute wiring pattern by removing the unwanted part of a seed layer by electrolytic separating means after the required wiring pattern is formed on insulating base material. SOLUTION: A bonding metal layer 6 such as chromium is uniformly formed on one surface of a required insulating base material 7. Furthermore, a seed layer 5 of copper and the like is formed on the surface of the bonding metal layer 6. Thereafter, the unncessary part of the seed layer 5 is masked by using photoresist and the like. Then, the signal layer or the different metal of the conductor of copper and the like is laminated and attached to the required part by an electrolytic plating means. Thus, required wiring pattern 4 is formed. Such a circuit board is arranged in an electrolytic bath 1, and the circuit board and a counter electrode 8 are connected to a DC power supply 9 and applied to the electrolytic separation process of the sheed layer 5, and the unwanted part is adequately removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a circuit board. The present invention relates to a method of manufacturing a circuit board capable of suitably removing an unnecessary portion of a shield layer without giving.

[0002]

2. Description of the Related Art As a means for manufacturing a circuit board by a semi-additive method, a required insulating base material 1 as shown in FIG.
0, an adhesive metal layer 12 of chromium or the like is uniformly formed on one surface thereof.
After the formation of the doped layer 11, the substrate is sealed using a photoresist or the like.
A required wiring pattern 13 is formed by masking an unnecessary portion of the doped layer 11 and then depositing a single layer or a dissimilar metal on the required portion by electrolytic plating.

In some cases, a corrosion-resistant metal layer 14 such as gold is deposited on the surface of the wiring pattern 13 formed by such a method.

[0004]

After the wiring pattern 13 is formed by the above-described method, an unnecessary region in the shield layer 11 is removed by etching means. In the step of etching the negative layer, side etching also proceeds on the wiring pattern 13 side as shown in FIG. 3, and the vicinity of the base of the wiring pattern 13 is excessively removed to form a side etching portion 15, Depending on the degree, the problem that the wiring pattern 13 is peeled off occurs.

Such a problem is a serious problem to be solved since it has a particularly significant effect when the wiring pattern 13 needs to be finely formed.

Accordingly, the present invention provides a method of forming a desired wiring pattern by electrolytic plating, and preferably removing unnecessary portions of a shield layer without damaging the wiring pattern. A possible method of manufacturing a circuit board is provided.

[0007]

Therefore, in the method of manufacturing a circuit board according to the present invention, a circuit for forming a required wiring pattern on an insulating base material by electrolytic plating means using a shield layer. In the method of manufacturing a substrate, unnecessary portions of the shield layer are removed by electrolytic stripping means after the formation of the wiring pattern.

Here, a corrosion-resistant metal layer may be formed on the surface of the wiring pattern.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be further described below with reference to the illustrated embodiments. As shown in FIG. 1, in order to manufacture a required circuit board, first, an adhesive metal layer 6 such as chromium is uniformly formed on one surface of a required insulating base material 7, and the adhesive After forming a seed layer 5 of copper or the like on the surface of the metal layer 6, an unnecessary portion of the seed layer 5 is masked by using a photoresist or the like. The required wiring pattern 4 is formed by laminating a single layer or a dissimilar metal.

Here, a corrosion-resistant metal layer 3 such as gold is formed on the surface of the formed wiring pattern 4.

The circuit board manufactured up to this stage is then placed in an electrolytic cell 1 filled with a required electrolytic solution 2,
The circuit board and the counter electrode 8 are connected to a DC power supply 9 to subject the seed layer 5 to electrolytic stripping.

By this electrolytic stripping process, the seed layer 5 is formed.
Unnecessary portions of the wiring pattern are appropriately removed,
In the case where the corrosion-resistant metal layer 3 such as gold is formed on the surface of the wiring pattern 4, it is possible to prevent the wiring pattern 4 from being undesirably damaged.

After the unnecessary portion of the shield layer 5 is removed by the above-described method, the unnecessary portion of the adhesive metal layer 6 is removed to obtain a required circuit board.

[0014]

According to the method of manufacturing a circuit board according to the present invention, when a required wiring pattern is formed on an insulating base material by an electrolytic plating means using a shield layer, the wiring pattern is formed.
Since unnecessary portions of the shield layer are removed by electrolytic stripping means after the formation of the pattern, even if the wiring pattern is fine, the shield layer is not damaged without damaging the wiring pattern. Unnecessary portions can be suitably removed.

Therefore, a high quality circuit board can be stably manufactured.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a step of removing a seed layer of a circuit board by electrolytic stripping means according to the present invention.

FIG. 2 is an explanatory view for forming a wiring pattern of a circuit board by an electrolytic plating method.

FIG. 3 is a diagram for explaining a problem that occurs when a seed layer is removed by etching means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrolyzer 2 Electrolyte 3 Corrosion-resistant metal layer 4 Wiring pattern 5 Shield layer 6 Adhesive metal layer 7 Insulation base material 8 Counter electrode 9 DC power supply

Claims (2)

[Claims] In a method of manufacturing a circuit board, wherein a required wiring pattern is formed on an insulating base material by electrolytic plating means using a seed layer, an electrolytic plating is performed after the formation of the wiring pattern. A method of manufacturing a circuit board, comprising: removing unnecessary portions of the seed layer by a peeling means. 2. The method according to claim 1, wherein a corrosion-resistant metal layer is formed on a surface of said wiring pattern.