JPS58110094A - Method of producing printed circuit 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 (1) Technical Field of the Invention The present invention relates to a method for manufacturing a printed wiring board, and in particular, the invention relates to a method for manufacturing a printed wiring board.
Printed wiring that enables high-density mounting In recent years, there have been remarkable developments in integrated circuit technology, and the mounting density of printed wiring boards on which these integrated circuits are mounted is also becoming higher and higher.

Under these circumstances, there is a demand for a printed wiring board with a high patterning rate and a dramatic increase in the number of connections between collector circuits on the printed wiring board.

(8) Prior Art and Problems FIGS. 1(a) to 1(2) are a plan view and a side sectional view for explaining the steps of a conventional printed wiring board manufacturing method.

In Fig. 1), 1 is a double-sided copper-clad laminate with copper foil 12 pasted on both sides of an insulating bit made of glass epoxy resin, etc., and Fig. The figure shows a view of A where a micrometer pilot hole 2 is drilled at the first position.
In Figure (Q), a conductive layer 8 is formed on the inner wall of the drilled through-hole .mu. hole 2 by electroless steel plating to form a null hole 4. The conductive layer 8 serves as a current-carrying layer in the next plating process, and the thickness of the plating is approximately 2 μm to 5 μm. Figure 1 (d
2), the land 6 corresponding to the through-hole μ4 of the double-sided rope laminated spring board l completed the above process, the pull-out signal pattern 18 of the scissor fundo and the predetermined wiring pattern 6 are removed by partial pressure screen printing or photo printing. Metsukire cyst 7 was applied using the I cyst method.

In FIG. 1(e), a fundo, an extraction signal pattern 18 for the fundo, and a wiring pattern 6 are formed on the double-sided steel clad laminate l on which the plating resist 7 has been applied by electroplating to a specified thickness. After removing an etching resist (not shown) on this land 6, the signal extraction signal pattern 18 and the wiring pattern 6 of the fundo, the through-holes 4/4. In the conventional printed wiring board manufacturing method, the conductive layer 8 and the copper foil 12 except for the lead-out signal pattern 1B and the wiring pattern 6 of the land 6 are removed, and then the etching resist made of the above-mentioned rock material is removed. be. However, the printed circuit board's sul m ho μ can only process l signals (
Figure example pull-out signal pattern 18) Due to the low number of patterns accommodated, the number of patterns is low and the pattern cannot be patterned and becomes a jumper line, resulting in a signal delay due to the longer pattern length, and a decrease in reliability due to the jumper connection line. This has the drawback of increasing costs and preventing high-density dormitories.

(4) Purpose of the Invention The present invention has been made in view of the drawbacks of the prior art.
The purpose of this is to divide the inner wall of the circuit into a plurality of parts to provide a new type of printed wiring that makes it possible to process multiple signal lines using one through hole.

(6) Structure of the Invention In order to achieve the above-mentioned object, the present invention provides a through-hole for a mesh laminate KIE number for 111111,
In the method of manufacturing a printed wiring board, a pilot hole for a through hole is formed in the double-sided steel clad laminate, and a conductive layer is formed on the inner wall of the pilot hole by chemical plating. This is achieved by dividing the inner wall of the hole along the hole direction into a plurality of parts so as to be insulated from each other, and forming a land corresponding to the inner wall of the divided through hole.

(6) Examples of the invention Manufacturing a printed wiring board according to the present invention with reference to the drawings below.
Examples of the method will be described in detail.

Figures 2-4 to (b) are plan views and gI for explaining one embodiment of the manufacturing process of the printed wiring board manufacturing method according to the present invention.
ll sectional view. In FIG. 2, the manufacturing method of the printed wiring board of the present invention is similar to that in FIG. The feature is that it is divided into multiple parts. Therefore, steps other than the second turn are given the same reference numerals as in FIG. 1 except for the pull-out pattern, and detailed explanations of these steps are omitted here. Form a through hole /I/8 divided by the notch 9
After removing the conductive layer 8 in the 0 part to expose the insulating layer 11, as shown in FIG. 2(e), a divided fund corresponding to the inner wall of the through hole lv8 which was divided into the previous TD and a signal extracted from the divided land. A mesh resist 7 is applied to a portion excluding patterns 14 to 17 and a predetermined wiring pattern 6 by a screen printing method or a photoresin method.

Fig. 2 (0 shows the land 5, the signal patterns 14 to 17 for drawing out the RiJ marked subdivided lands, and the wiring pattern 6 formed by the electroplating method; The process of removing the conductive layer 8 and the steel foil 12 by removing and etching is similar to the conventional process.

In addition, in this embodiment, the number of through holes/L/8 1111 is 4, but depending on the purpose, 2 or 8 holes may be used. It can also be applied to each layer.

(7) Effects of the Invention As is clear from the above explanation, according to the method of manufacturing a printed wiring board according to the present invention, by applying a through hole divided into a plurality of parts compared to the conventional through hole /I/, the conventional through hole Although a single pattern is rarely used, multiple signals can be connected by aJ and Il, and jumper wires and the like are not required, so reliability can be expected to be improved and a printed wiring board with high density packaging can be provided.

[Brief explanation of the drawing]

Figures 1 (a) to (2) are a plan view and side sectional view for explaining the steps of a conventional printed wiring board manufacturing method, and Figure 2 (a)
) to (5) are a plan view and a side sectional view for explaining one embodiment of the manufacturing process of the printed wiring board manufacturing method according to the present invention. In the figure, l is a double-sided steel clad laminate, 2 is a through-hole prepared hole, 8 is a conductive layer, 4 is a through hole, 5 is a land, 6 is a wiring pattern, 7 is a mesh resist, 8 is a divided through hole, and 9 is a notch. , 11 is an insulating layer, 12 is a copper foil, 18-
17 shows a land extraction signal pattern. 1st WJ 11th! I

Claims (1)

[Claims] In a method for manufacturing a double-sided copper-clad laminate in which a plurality of through-holes and lands corresponding to the holes are formed, pilot holes for through-holes are drilled in the double-sided steel-clad laminate, and A conductive layer is formed in the pilot hole by chemical plating, and the inner wall along the hole direction of the through hole is divided into a plurality of parts so as to be mutually insulated, and a land corresponding to the inner wall of the nine divided holes is formed. A method for manufacturing a printed wiring board, characterized in that a printed wiring board is formed.