JP2002329964A - Method of manufacturing multilayer printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of getting a highly accurate printed wiring board by suppressing misregistration simply, in a manufacturing method for a multilayer printed wiring board. SOLUTION: A reference hole in a layer lower than wiring formation layers 5 and 6 is filled with magnetic substances 4, and register with a lamination matter is performed by visualizing the reference hole on the wiring formation layers 5 and 6 by magnetic particles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a multilayer printed wiring board, and more particularly to a method for aligning a wiring forming layer and an exposure mask, aligning an inner layer substrate when laminating, and aligning a via hole and a through hole. And a method for performing various alignments with high accuracy.

[0002]

2. Description of the Related Art A multilayer printed wiring board is formed by laminating an inner layer substrate on which wiring is formed, a prepreg, and a substrate for an outer layer, and then forming a through hole or an outer layer wiring, or an insulating layer on the wiring forming layer of the inner layer substrate. After forming via holes, forming a copper layer by copper plating etc., then forming wiring using this copper layer, further applying an insulating layer and building up the upper wiring board It is manufactured by a method or the like.

When a multilayer printed wiring board is manufactured, it is important to accurately adjust the wiring position of each layer and the position of a through hole. As a positioning method, a method using a reference hole is generally used. The reference hole method is a method of performing alignment in all of the subsequent manufacturing steps based on the inner layer reference hole provided in the inner layer substrate, thereby suppressing the displacement of the wiring and the through hole.

For example, first, a reference hole is provided in an inner layer substrate,
The reference hole is aligned with the alignment mark on the exposure mask for manufacturing an inner layer wiring to form a wiring on the first inner layer substrate.
On this, a single-sided copper-clad laminate is stacked, and while confirming the reference hole of the inner layer substrate by X-rays or the like, formation of via holes and through holes, copper plating processing, wiring formation processing using a resist and an exposure mask are performed, Manufacture multilayer printed wiring boards.
In addition, a reference hole is provided in both the inner layer substrate and the outer layer substrate, and a guide pin is inserted and fixed in the reference hole and thermocompression-bonded,
Next, there is a method of forming a through hole or an outer layer wiring.
However, confirmation of the reference hole by X-ray has a disadvantage that it is difficult to manage the X-ray apparatus. In the method of providing the reference holes in both the inner layer substrate and the outer layer substrate, when laminating and thermocompression bonding, the difference in the heat shrinkage between the inner layer substrate and the outer layer substrate causes a shift in the position of the reference hole or the shape of the reference hole. There was a problem that would change. In addition, there has been a problem that as the wiring density and the number of layers of the multilayer printed wiring board increase, the displacement of the reference holes increases.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a multilayer printed wiring board, which suppresses misalignment and obtains a printed wiring board with high accuracy.

[0006]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that in a method for manufacturing a multilayer printed wiring board, a magnetic material is filled in advance in a reference hole below a wiring forming layer, and wiring is performed by magnetic particles. It has been found that the reference holes may be visualized on the formation layer and alignment with the laminate may be performed. According to the present invention, since the position of the reference hole of the inner layer substrate can always be confirmed on the outermost layer substrate which is the wiring forming layer, the position can be easily confirmed. Further, even if the position of the outer layer substrate and the inner layer substrate is shifted or the shape of the reference hole of the outer layer substrate is changed, the position of the reference hole can be accurately confirmed.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail. FIG. 1 is a schematic view of a printed wiring board, where 2 is a reference hole and 3 is a product area. In the present invention, as shown in FIG. 14, a magnetic material is filled in a reference hole provided in an inner layer substrate below a wiring forming layer of a multilayer printed wiring board. Thereafter, the number of layers is increased by a lamination method or a build-up method. When wiring is formed on each layer, the magnetic particles 11 are formed on the wiring forming layer.
Thus, the reference holes are visualized, and are used, for example, as a position reference for aligning an exposure mask or opening a via hole or a through hole with a laser. Finally, in the printed wiring board 1 of FIG.
Are discarded, so that the reference hole 4 filled with the magnetic material,
Magnetic particles 11 used to visualize the position of the reference hole
Does not adversely affect the product.

[0008]

Hereinafter, the present invention will be described in detail with reference to Examples.
The present invention is not limited to the following examples as long as the gist is not exceeded.

2 to 13 are sectional views showing one embodiment of the present invention in the order of steps. First, as shown in FIG. 2, a reference hole 2a is formed in the first double-sided copper-clad laminate for an inner substrate. Then, as shown in FIG. 3, by a known method,
Wiring is formed on the first inner substrate 8 using a resist material. When wiring is formed using this resist material,
Positioning is performed using the reference holes 2a and the positioning marks of the exposure mask for forming the inner layer wiring.

Similarly, after manufacturing the second inner substrate 9 having a different wiring pattern, a magnetic material is filled into the reference holes of the second inner substrate (4b). As shown in FIG.
The insulating layer (prepreg) 10 is superimposed on the inner substrate, and the positions of the reference holes visualized by the magnetic particles 11 on the prepreg are aligned with the reference holes 2a of the first inner substrate.
Laminate. As shown in FIG. 5, after the laminate is bonded by vacuum pressure, a magnetic material is filled into the reference hole of the first inner layer substrate 8 (4a).

Next, as shown in FIG. 6, a via hole 12 is formed. At this time, the reference holes 4a and 4b are used for positioning. Subsequently, as shown in FIGS. 7 and 8, the entire surface is subjected to panel plating, and a wiring is formed on the surface of the stacked body 13 using a resist material. When wiring is formed using this resist material, as shown in FIG. 7, the positions of the reference holes 4a and 4b are aligned with the magnetic particles 1 on the copper layer.
It is visualized by 1 and used for alignment with the alignment mark of the exposure mask.

Further, as shown in FIG. 9, after the laminate 13 and the single-sided copper-clad laminates 14a and 14b are laminated under vacuum and pressure,
The position of the reference hole 4a is visualized on the copper layer with the magnetic particles 11, and as shown in FIG. 10, a through hole 16 is formed based on the reference hole 4a. Next, as shown in FIG. 11, after the entire surface is plated, the positions of the reference holes 4a and 4b are visualized on the copper layer with the magnetic particles 11. As shown in FIG. 12, a wiring pattern of the outermost layer is formed using the resist material while aligning the magnetic particles 11 with the exposure mask. Finally, as shown in FIG. 13, the area where the reference holes 4a and 4b exist is discarded to obtain a final product.

In the method of manufacturing a multilayer printed wiring board according to this embodiment, the positioning can be performed without using an X-ray apparatus or the like. In addition, the deviation between the inner layer substrate 8 and the outermost layer substrate was 10 μm on average in the method using the guide pins, but was 3 μm on average in the method of the present invention, so that a more accurate printed wiring board could be obtained. It was confirmed.

[0014]

As described above, in the method for manufacturing a printed wiring board of the present invention, the position of the reference hole of the inner layer substrate can be easily and accurately grasped in all the steps, so that a high-precision printed wiring board can be obtained. Has an excellent effect that can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of a reference hole setting position in a method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 2 is a cross-sectional view showing one step in a method for manufacturing a multilayer printed wiring board in one embodiment of the present invention.

FIG. 3 is a sectional view showing a step following the step shown in FIG. 2 in the method for manufacturing a multilayer printed wiring board in one embodiment of the present invention.

FIG. 4 is a sectional view showing a step following the step shown in FIG. 3 in the method for manufacturing a multilayer printed wiring board in one embodiment of the present invention.

FIG. 5 is a sectional view showing a step following the step shown in FIG. 4 in the method for manufacturing a multilayer printed wiring board in one embodiment of the present invention.

FIG. 6 is a sectional view showing a step following the step shown in FIG. 5 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 7 is a sectional view showing a step following FIG. 6 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 8 is a sectional view showing a step following the step shown in FIG. 7 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 9 is a sectional view showing a step following the step shown in FIG. 8 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 10 is a sectional view showing a step following the step shown in FIG. 9 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 11 is a sectional view showing a step following the step in FIG. 10 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 12 is a cross-sectional view showing a step following the step shown in FIG. 11 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 13 is a sectional view showing a step following the step shown in FIG. 12 in the method of manufacturing the multilayer printed wiring board in one embodiment of the present invention.

FIG. 14 is a schematic cross-sectional view showing a method of visualizing a reference hole position of an inner layer substrate in a wiring forming layer in a method of manufacturing a multilayer printed wiring board of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2, 2a, 2b Reference hole 3 Product area 4, 4a, 4b Reference hole filled with magnetic material 5 Copper layer 6 Insulating layer 7 Inner substrate through hole 8 First inner substrate 9 Second inner substrate 10 Insulation Layer (prepreg) 11 Magnetic particles 12 Via hole 13 Laminated body 14a, 14b Single-sided copper-clad laminate 15 Laminated body 16 Through hole

Claims (1)

[Claims] In a method for manufacturing a multilayer printed wiring board, a reference material below a wiring formation layer is filled with a magnetic substance in advance, and the reference holes are visualized on the wiring formation layer by magnetic particles to form a laminate. A method for manufacturing a multilayer printed wiring board, comprising: