JP2001230520A - Method of manufacturing wiring board and wiring board obtained thereby - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a printed board which can simplify the process for manufacturing a wiring board, and a wiring board obtained by the method. SOLUTION: A metal mold 11 for transfer in which protruding parts 13 are formed and drilling pins 12 are disposed upright, is installed in a metal mold 17 for injection molding, in such a manner that the protruding parts 13 face toward the inside. With this injection molding machine, a board material 14 is introduced and fused through heating. The board material in a fused state is injected in a metal mold cavity 17a of the metal mold 17 from a feed opening 16. In this case, the metal mold 17 is pressed from above with a prescribed pressure. By performing injection molding with the metal mold 17 using the board material 14, a molded article 18 having trenches 19 and molding holes 20 can be obtained.

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 wiring board on which electronic components and the like are mounted and a wiring board obtained by the method.

[0002]

2. Description of the Related Art Generally, in a process of manufacturing a wiring board such as a printed wiring board, when a through hole for interlayer connection is formed in the wiring board, a drilling step using a drill or a laser, a plating step, a filling material filling, and the like. A plurality of processes such as a process and a planarization process are required.

When a through-hole is formed in such a process, an interlayer connection failure occurs due to a drilling failure in the drilling process, a connection failure occurs due to entrapment of air bubbles in a plating process, or a filler material in a filler embedding process. In some cases, voids may occur due to defective filling, or defects may occur due to adhesion of polishing dust in the flattening step.

In the manufacturing process of a wiring board,
Having a plurality of steps may complicate the process, increase the manufacturing cost, further decrease the product yield, cause variations in product performance, and deteriorate reliability.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a method of manufacturing a wiring board which can simplify the steps of manufacturing the wiring board, and a wiring board obtained by the method. The purpose is to:

[0006]

Means for Solving the Problems In order to solve the above problems, the present invention has taken the following means. The present invention relates to a method of manufacturing a wiring board by supplying a substrate material to a mold having a cavity of a predetermined shape and molding the same, wherein a convex pattern to be transferred to the wiring board is formed on one main surface. A step of forming a cavity on the one main surface side by mounting a transfer mold in which pins corresponding to through holes of the wiring board are erected on a mold body.
Providing a substrate material to the cavity to form a wiring board.

According to this method, a groove for a wiring pattern is formed at the time of molding, and a through hole is formed. Therefore, it is not necessary to perform a through hole hole forming step in a separate step. For this reason, simplification of a processing step can be realized, and processing time and processing cost can be reduced.

According to the present invention, there is provided a transfer mold in which a convex pattern to be transferred to a wiring board is formed on one main surface and pins corresponding to through holes of the wiring board are provided upright. To provide a wiring board obtained by a step of forming a cavity on the one main surface side and a step of supplying a substrate material to the cavity to form a wiring board.

According to this structure, since the groove for the wiring pattern and the through hole are formed at once during molding, the positional accuracy between the wiring pattern and the through hole is extremely high. For this reason, through-hole lands conventionally provided can be eliminated, which is advantageous in designing a high-density wiring pattern.

[0010]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a diagram for explaining a method of manufacturing a wiring board according to an embodiment of the present invention, and FIG. 1A is a diagram illustrating a transfer mold for transferring a groove serving as a wiring pattern. (B) is a diagram showing a molding die on which a transfer die is mounted, and (c) is a diagram showing a completed wiring board obtained by molding.

In this method of manufacturing a wiring board, FIG.
A transfer mold as shown in FIG. The transfer mold 11 has a projection 13 formed on one main surface at a portion corresponding to the wiring pattern of the wiring board. That is,
The projections 13 correspond to the grooves of the wiring board when the wiring board is molded, and the wiring pattern is formed by filling the grooves with a conductive material.

Drilling pins 12 are provided upright on specific projections 13 on one main surface of the transfer mold 11, that is, on portions corresponding to the through-hole lands. That is, when the wiring board is formed, the drilling pins 12 correspond to through-hole portions of the wiring board. Due to the presence of the drilling pins 12, the substrate raw material is not filled, and the through-holes are formed as through-holes.

As shown in FIG. 1B, the transfer mold 11 having the projections 13 formed and the piercing pins 12 erected is injected into the injection molding metal with the projections 13 facing inward. Type 17
Attach to Thus, a mold cavity 17a is formed inside the injection mold 17 (on the side of the convex portion 13). A resin supply port 16 is provided on a side surface of the injection mold 17, and the supply port 16 communicates with the mold cavity 17 a. Further, an injection member 15 is connected to the injection molding machine provided with the injection molding die, and the resin as the substrate raw material 14 is injected.

When the substrate raw material 14 is charged by the injection molding machine having such a configuration, the substrate raw material 14 is heated and melted, and the molten substrate raw material is supplied from the supply port 16 to the injection molding die 17.
Is injected into the mold cavity 17a. At this time, the injection molding die 17 is pressurized at a predetermined pressure from above.

By performing the injection molding with the injection molding die 17 using the substrate raw material 14 in this manner, FIG.
Is obtained. In this molded product 18, a groove 19 transferred is formed corresponding to the convex portion 13 of the transfer mold 11, and a forming hole (through hole) 20 is formed corresponding to the piercing pin 12 of the transfer mold 11. Is formed. Since the groove 19 and the forming hole 20 are formed at one time, the positioning accuracy is very good. The trench 19 is filled with a conductive material such as a conductive paste to form a wiring.

As described above, in the method of manufacturing a wiring board according to the present embodiment, since a groove for a wiring pattern is formed and a through hole is formed during molding, it is necessary to form a through hole in a separate step. Disappears. For this reason, simplification of a processing step can be realized, and processing time and processing cost can be reduced.

In the wiring board obtained by this method, since the groove for the wiring pattern and the through hole are formed at the same time during molding, the positional accuracy between the wiring pattern and the through hole is extremely high. Become. For this reason, through-hole lands conventionally provided can be eliminated, which is advantageous in designing a high-density wiring pattern.

As described above, since the positional accuracy between the wiring pattern and the through-hole is extremely good, as shown in FIG. 2, the through-hole landless wiring board 23 having no through-hole land is formed by the method of the present invention. It is possible to realize. Thereby, the space between the through hole 21 and the pattern 22 can be narrowed, which is advantageous for designing a high-density wiring pattern.

The present invention is not limited to the above embodiment, but can be implemented with various modifications. In the above embodiment, the case where the molding is injection molding has been described, but the present invention can also be applied to a case where a wiring board is manufactured by press molding.

[0020]

As described above, in the method of manufacturing a wiring board according to the present invention, a groove for a wiring pattern is formed at the time of molding and a through hole is formed. Disappears. For this reason, simplification of a processing step can be realized, and processing time and processing cost can be reduced.

Further, in the wiring board of the present invention, since the groove for the wiring pattern and the through hole are formed at one time at the time of molding, the positional accuracy between the wiring pattern and the through hole becomes extremely high. For this reason, through-hole lands conventionally provided can be eliminated, which is advantageous in designing a high-density wiring pattern.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a method of manufacturing a wiring board according to one embodiment of the present invention, and FIG. 1 (a) is a diagram illustrating a transfer mold for transferring grooves for a wiring pattern; ,
(B) is a diagram showing a molding die on which a transfer die is mounted, and (c) is a diagram showing a completed wiring board obtained by molding.

FIG. 2 is a diagram illustrating an example of a through-hole landless wiring board.

[Explanation of symbols]

11: Transfer mold, 12: Drilling pin, 13: Convex part, 1
4 ... substrate raw material, 15 ... input member, 16 ... supply port, 17
... injection mold, 17a ... mold cavity, 18 ... molded product, 19 ... groove, 20 ... mold hole, 21 ... through hole,
22: pattern, 23: wiring board.

Claims (2)

[Claims] 1. A method of manufacturing a wiring board by supplying a substrate material to a mold having a cavity having a predetermined shape and forming the same, wherein a convex pattern to be transferred to the wiring board is formed on one main surface. A step of forming a cavity on the one main surface side by mounting a transfer mold, which is formed and provided with pins corresponding to through holes of the wiring board, upright on the mold body, Supplying a substrate material to form a wiring board. 2. A transfer mold in which a convex pattern to be transferred to a wiring board is formed on one main surface, and a transfer mold having pins corresponding to through holes of the wiring board is mounted on the mold body. A wiring substrate obtained by performing a step of forming a cavity on the one main surface side, and a step of supplying a substrate material to the cavity to form a wiring substrate.