JPH01194391A - Manufacture of wiring board - Google Patents

Abstract

PURPOSE:To remove resist deviation and to obtain a wiring board with high concentration and improved connection reliability by drilling an electrical signal passing penetration hole after forming a plating resistant solder resist on it. CONSTITUTION:A resist ask is provided to a base material 2 laminated by a copper foil 1 for performing etching. Packaging pad and electrical signal passing penetration hole other than penetration for inserting parts are covered by a plating resistant solder resist 6. A hole 8 is provided to give a catalyst to the inner wall except a copper-clad laminated with catalyst. Then, electroless copper plating is performed at least to the inner wall of hole. This configuration simplifies the production process and allows a wiring board with high concentration and improved connection reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a wiring board in which the inside of a hole made after a plating-resistant solder resist treatment is electrolessly plated with copper.

[Conventional technology]

The manufacturing methods for wiring boards can be roughly divided into subtractive method,
Full additive method, semi-additive method, part-time method
There is an additive method.

As shown in the step-by-step explanatory diagram in Figure 3, the part-additive method involves (1) copper-clad laminates, (2) drilling, and (3)
Catalyst application, (4) Etching resist, (5) Etching, (6) Peeling, (7) Plating resistant solder resist, (8
) It is generally performed by each step of electroless plating.

The method described in Japanese Patent Application Laid-Open No. 59-155994 is noteworthy because it simplifies the manufacturing process using the part-additive method, reduces manufacturing costs, and makes it possible to cope with mass production. The order of the manufacturing process is the same as before.

[Problem to be solved by the invention]

In this conventional method, in step (7) shown in FIG. 3, plating-resistant turder resist 1 is applied to other parts except the land portion and the through hole, but is not applied to prevent the resist from entering the through hole. It is necessary to widen the area, and as a result, there is a problem that the circuit density on the surface of the wiring board decreases. Further, when this plating-resistant solder resist enters the through hole, there is a problem that the plating does not adhere to that part, resulting in poor connection reliability between the wiring board and the wiring board and the mounted components.

[Means to solve the problem]

The present invention is a method that simplifies the manufacturing process of a wiring board and also provides high density and high connection reliability.

Embodiments of the present invention will be explained in the order of manufacturing steps with reference to the drawings.

In Figure 1, (1) a copper-clad laminate, (2) etching resist applied, (3) unnecessary parts removed by etching, and (4) etching resist removed if necessary, but it is not necessary to remove it. , (5) Applying a plating-resistant solder resist. solder resist.

It is necessary to apply it to the entire surface including the electrical signal via through hole portion, excluding at least the surface mount pad and component insertion through hole pad portion. (6) Drill holes. As the hole, a through hole or a non-through hole can be used. (7) Applying a catalyst to the inner wall of the hole is not performed when using a copper-clad laminate containing a catalyst. (8) Electroless copper plating is performed on at least the inner wall of the hole. FIG. 2 shows another example using a catalyst-containing copper-clad laminate.

[Effect]

In the manufacturing method according to the present invention, the holes are drilled after forming the plating-resistant solder resist on the electrical signal via through-hole portion, so there is no displacement of the plating-resistant solder resist, making it possible to manufacture a high-density wiring board. Also, for the same reason, there is no adhesion of anti-plating solder resist inside the holes, improving connection reliability.

〔Effect of the invention〕

With the present invention, the distance between the circumference of the through hole and the line, which conventionally required 0.5 m or more, can be made as close as 0.2 mm, reducing the surface circuit density of the wiring board by 1.
．． We were able to improve it by 5 times. Additionally, the manufacturing process has been simplified and connection reliability has increased.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views for explaining each manufacturing process according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view for explaining a conventional method. DESCRIPTION OF SYMBOLS 1... Copper foil, 2... Base material, 3... Penetrating through hole, 4... Catalyst, 5... Etching resist, 6...
... Plating-resistant solder resist, 7... Electroless copper plating, 8... Through-hole via electric signal, 9... Surface component connection pad, 10... Base material containing catalyst, 11... Inner layer circuit , 12...Non-penetrating through hole.

Claims (2)

[Claims] 1. When manufacturing wiring boards from copper-clad laminates using the part-additive method, a plating-proof solder resist is applied to the entire surface including the through-holes for electrical signals, excluding at least the surface-mounted component connection pads and component insertion through-hole pads. A method for producing a wiring board, which comprises performing electroless copper plating on the holes drilled after forming the wiring board. 2. 2. The method of manufacturing a wiring board according to claim 1, wherein the copper-clad laminate is made of a base material containing a plating catalyst.