JPS63173391A - Multilayer printed interconnection board and manufacture of the same - 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] [Industrial application field] The present invention relates to a multilayer printed wiring board and a method for manufacturing the same.

[Conventional technology]

In recent years, there has been an increasing demand for higher density and higher multilayer multilayer printed wiring boards (hereinafter referred to as wiring boards). Therefore, the deviation in dimensional accuracy between the inner layer circuit pattern formed in the inner layer portion of the wiring board and the through hole has become a serious problem in terms of electrical connection. Next, a conventional method for manufacturing a wiring board will be described using FIGS. 7 to 10.

First, as shown in Fig. 7 (a>, (b)) and Fig. 9,
Guide holes 7 are provided at the four corners of the periphery of the upper mold 11B and the lower mold 11A of the laminated mold, and at least a pair of opposing reference holes 9 are provided.

On the other hand, a laminate 10 in which an inner layer material consisting of a prepreg 3 and an inner layer substrate 4 is inserted inside an outer layer material 2 having an outer layer copper foil 1 adhered to its surface, is prepared in advance by forming a lower mold 11A and an upper mold 11B of the lamination mold. A stacking guide hole 7A and a stacking reference hole 9A are formed at positions that are mutually aligned with the guide hole 7 of FIG.

As shown in FIG. 8, the lamination order of the laminated plates 10 is as follows: First, metal lamination guide pins 6 and reference pins 8 are planted in the lower die 11A of the lamination mold. Next, the prepreg 3 and the inner layer substrate 4 are inserted and placed between the upper and lower outer layer materials 2, and the upper mold 1. Put IB on it. Subsequently, the laminate 1 is integrally formed by heating and pressurizing it on a Hola I press. After forming the OA, remove the laminated guide pin 6 and the reference pin 8,
The laminate 10A is put into a laminate mold 11. A. Remove from IIB.

Next, as shown in FIG. 10, the NC guide pin 13 to be used in the next through-hole forming process is inserted into the stack reference hole 9A of the stack 10A, and the NC guide pin 13 is inserted into the stack reference hole 9A of the stack 10A.
After forming a through hole at a desired position of 0A (not shown), electroless plating and electroplating are performed to form a through hole plating layer (not shown) in the through hole. Furthermore, a photosensitive resin is applied to the outer layer copper foil 1 on the surface of the outer layer material 2, and exposed to light through a photo mask aligned with the aforementioned through holes to form an etching resist film. Next, unnecessary portions of the outer layer copper foil 1 are removed using an etching solution to form an outer layer circuit pattern, thereby obtaining a desired wiring board. Furthermore, the inner layer positional deviation of each layer is inspected by measuring the dimensions using the lamination reference hole 9A as a reference.

In this manner, in the conventional wiring board, the positional relationship between the through-hole plating layer, the outer layer circuit pattern, and the inner layer circuit pattern was established based on the lamination reference hole 9A.

[Problem that the invention seeks to solve]

In the conventional wiring board manufacturing method described above, the reference pin 8 is directly inserted into the lamination reference hole 9A of the laminated board 10 as shown in FIG. 9, and therefore has the following drawbacks.

(a) Since the contact area between the reference pin 8 and the inner layer substrate 4 is small, it is vulnerable to horizontal pressure against the reference pin 8 during lamination pressurization, and the inner layer substrate 4 is likely to be misaligned. (b) When pulling out the reference pin 8 from the laminate 10A after lamination pressurization is completed, the hole edge of the laminate reference hole 9A of the laminate 10A may be deformed or damaged, resulting in a reference position for the subsequent process. Visual errors are likely to occur during confirmation work. (c) Therefore, dimensional deviations are likely to occur between the inner layer circuit pattern and the through hole.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide a multilayer printed wiring board with no dimensional deviation between inner layer circuit patterns and through holes, and a method for manufacturing the same.

[Means for solving problems]

A multilayer printed wiring board according to a first aspect of the invention includes a laminate, guide holes drilled at four corners of the laminate, and at least a pair of openings provided opposite to a peripheral edge of the laminate. , and a hollow cylindrical body fitted into the opening.

The method for manufacturing a multilayer printed wiring board according to the second aspect of the invention is to form lamination guide holes in the four corners of the inner layer material, which is the one-layer substrate and the prepreg, and to form at least one pair of openings facing the periphery of the inner layer material. a step of fitting a hollow cylindrical body into the opening of the inner layer material, inserting a reference pin into the center hole of the hollow cylindrical body and a guide pin into the guide hole; After heating and pressurizing the inner layer material inserted from above and below to form a laminate, and removing the reference pin and guide pin from the laminate, Koumei inserts a guide pin into the center hole of the hollow cylindrical body. and forming a through hole at a predetermined position in the laminate.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an enlarged sectional view of the vicinity of a metal ring, which is a hollow cylindrical body, of a first embodiment of the multilayer printed wiring board of the present invention. Hereinafter, it will be explained along with its manufacturing method.

FIGS. 2(a) and 2(b) are a plan view and a cross section taken along the line A-A' of a laminated mold sandwiching a laminated plate for explaining an embodiment of the method for manufacturing one sheet of multilayer printed wiring 6 of the present invention. 3 and 3 are cross-sectional views when guide pins are planted in the lower die, and FIGS. 4 and 5 are enlarged cross-sectional views of the vicinity of the metal ring shown in the order of manufacturing steps.

First, as shown in FIG. 3, the guide holes 7 provided at the four corners of the lower die 1 of the laminated mold and the reference holes provided opposite to the peripheral edge of the laminated mold are provided with laminated guide pins 6 and reference pins, respectively. 8
to be planted. A metal ring 5 made of brass or the like and having an inner diameter approximately equal to the outer diameter of the reference pin 8 is attached to the reference pin 8.
Fit together.

Next, as shown in FIGS. 2(a), (b) and 4,
Lamination guide holes 7A are formed at the four corners of a laminated board 10, which is constructed by stacking outer layer materials 2 having outer layer copper foils 1 on the outer surfaces of a plurality of inner layer materials consisting of prepregs 3 and inner layer substrates 4.
A pair of openings having a diameter approximately equal to the outer diameter of the metal ring 5 are formed around the opening. Next, the outer layer base material 2 and the inner layer substrate 4 are sequentially stacked and arranged with the prepreg 3 interposed on the lower mold 11A of the laminated mold set in a hot press (not shown), and the upper mold 1'IB is placed on top. Heat and pressure are applied to form a laminate 10A.

Next, the laminated guide pin 6 and reference pin 8 are pulled out from above using known mechanical means. During this heating and pressurization, the resin 3A flowing out from the prepreg 3 on the upper and lower sides of the metal ring 5 hardens and fixes the mold ring 5 to the laminate 10A.

In the process of forming a through hole using an NC drilling machine, as shown in FIG. . Thereafter, a through-hole plating layer (not shown) and an outer layer circuit pattern are formed in the same manner as in the prior art to obtain the desired multilayer printed wiring board shown in FIG.

Furthermore, in the inspection of the inner layer pattern dimensions in the OA (laminate), the resin 3A on the top surface of the metal ring 5 is scraped off, and the dimensions are measured using the center hole 9B of the ring as a reference position, and the inner layer position of each layer is measured with high precision. It becomes possible to do so.

As described above, in the multilayer printed wiring board of the present invention, an opening is provided opposite to the peripheral edge of the laminate 10A, and the metal ring 5 into which the reference pin is inserted is fitted into the opening to make contact with the inner layer substrate. By increasing the area, misalignment between the inner layer substrates becomes less likely to occur, and furthermore, the holes in the laminate do not cause errors in the reference positions used in the process. Therefore,
The dimensional deviation between the inner layer circuit pattern and the through hole is extremely small.

FIG. 6 is an enlarged sectional view of the vicinity of the metal ring of the second embodiment of the multilayer printed wiring board of the present invention. This second example is
The upper part of the metal ring 5 is formed in direct contact with the laminated mold 11b, and the manufacturing method is almost the same as the above-mentioned method.

In this second embodiment, the center hole 9B can be used as a reference hole without removing the resin 3A on the upper surface of the metal ring 5 in the embodiment shown in FIG. 1, so there is no need to remove the resin 3A. There is an advantage that there is no need to worry about damaging the surface of the metal ring 5 while removing the resin 3A, making the shape of the center hole 9B unclear, and deteriorating the positioning accuracy.

As explained above, the present invention provides at least a pair of openings facing the peripheral edge of the laminate, and a hollow cylindrical body into which the reference pin is inserted, thereby increasing the contact area with the inner layer substrate. By increasing , it is possible to prevent dimensional deviation between the inner layer circuit pattern and the through hole.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a first embodiment of the multilayer printed wiring board of the present invention, and FIGS. 2(a) and (b) are for explaining an embodiment of the method for manufacturing the multilayer printed wiring board of the present invention. A plan view and a cross-sectional view taken along the line A-A' of the laminated mold sandwiching the laminated body, FIG. 3 is a cross-sectional view when the guide pin is installed in the lower mold, and FIGS. 4 and 5 show the manufacturing process. FIG. 6 is a cross-sectional view of the second embodiment of the multilayer printed wiring board of the present invention, and FIGS. 7(a) and (b) are enlarged sectional views of the vicinity of the metal ring shown in order. A plan view and a cross-sectional view taken along the line B-B'' of a laminated mold sandwiching a laminated plate for explaining the manufacturing method, FIG. 8 is a cross-sectional view when a guide pin is installed in the lower mold, Fig. 10 is an enlarged cross-sectional view of the vicinity of the reference hole shown in the order of steps to explain the conventional method for manufacturing a multilayer printed wiring board. 1... Outer layer copper foil, 2... Outer layer material, 3...・Prepreg, 3A... Resin, 4... Inner layer substrate, 5... Metal ring, 6... Laminated guide pin, 7... Guide hole, 7A... Laminated guide hole, 8... Reference pin, 9...
・Reference hole, 9A... Lamination reference hole, 9B... Center hole,
10... Laminate, IOA... Laminate, IIA...
Lower type, IIB...upper type. A 1st section 4th figure 3rd section 5th figure 6th figure 7th figure 711A 9th figure 8th figure 10th figure

Claims (2)

[Claims] (1) A laminate, guide holes drilled at the four corners of the laminate, at least a pair of openings provided facing the periphery of the laminate, and a pair of holes fitted into the openings. A multilayer printed wiring board comprising a hollow cylindrical body. (2) A step of forming lamination guide holes in the four corners of the inner layer material, which is the inner layer substrate and the prepreg, and at least a pair of openings facing the peripheral edge of the inner layer material, and forming a hollow hole in the opening of the inner layer material. After fitting the cylindrical bodies, a step of inserting a reference pin into the center hole of the hollow cylindrical body and a guide pin into the guide hole, and heating and applying the inner layer material into which the reference pin and the guide pin are inserted from above and below. Pressing to form a laminate;
After removing the reference pin and guide pin from the laminate,
A method for manufacturing a multilayer printed wiring board, comprising the step of inserting a hole-making guide pin into the center hole of the hollow cylindrical body to form a through hole at a predetermined position of the laminate.