JPS60171790A - Mold for bonding laminated layer of multilayer 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 [Field of Application of the Invention] The present invention relates to a mold for laminating and bonding multilayer printed wiring boards, and in particular, to prevent "misalignment" between printed wiring boards constituting the multilayer printed wiring board. The aim was to manufacture multilayer printed wiring boards that were free of oxidation. This invention relates to a mold for laminating and bonding multilayer printed wiring boards.

[Background of the invention]

A conventional method for manufacturing a multilayer printed wiring board will be explained using one drawing.

Figures 1 and 2 are for explaining a conventional method for manufacturing a multilayer printed wiring board. Figure 1 is a perspective view showing the material and guide pins of the multilayer printed wiring, and Figure 2 is a laminate. FIG. 2 is a perspective view showing an example of a lamination adhesion mold for pressurizing this.

First, as shown in FIG. 1, a plurality of printed wiring boards 1 and synthetic resin foils 2 with guide holes 1a drilled at predetermined positions are alternately stacked, and guide pins 6 (made of steel) are inserted into the guide holes 1α. Position between each printed wiring board 1 by inserting the
A laminate 5 as shown in FIG. 2 is made. The upper and lower ends of the guide pin 5 remain in this state.

Upper mold 4. The guide holes 4α and 6α formed in the lower mold 6 (both made of steel) are made to have a low weight.

The upper mold 4 and the lower mold 6 are sandwiched, and this is loaded between the bolsters (heating plates) attached to the lower bed on the press (not shown), and the upper mold 4 ．． Lower mold 6
．． The laminate 5 is pressurized and heated by the bolster. Thereafter, the heat and pressure are removed, and the upper mold 4 for lamination bonding is removed from between the bolsters. When the lower mold 6 and the guide pins 5 are removed, the lamination adhesion of each printed wiring board 1 of the laminate 5 is completed and a multilayer printed wiring board is obtained.

In the multilayer printed wiring boards manufactured by the conventional method described above, "slipping" often occurs between each printed wiring board 1 after lamination and bonding, and when such misalignment occurs, the multilayer printed wiring boards When through-holes (not shown) 6 are formed in the board to connect each printed wiring board 1, wiring errors may occur, resulting in a defective product.

The causes of the deviation are thought to be the effects of dimensional changes of each printed wiring board 1 due to heating and pressure during wiring formation and lamination bonding, and dimensional changes of synthetic resin foil 2 during lamination bonding. ing.

Among these, in particular, by heating during the lamination bonding,
The difference in thermal strain between the lower mold 4.6 and the printed wiring board 1 is 0.1
This is largely due to the fact that thermal strain occurs to the extent shown in the figure (printed wiring board 1 has larger thermal strain than upper and lower molds 4.6). That is, due to the difference in thermal strain, the guide pin 5 inserted into the printed wiring board 1, which has a large elongation, moves upward.

Since it is restrained by the lower mold 4.6, a local external force acts on the printed wiring board 1 near the guide pin 5, causing local deformation, which causes misalignment between the printed wiring boards 1. be.

Conventionally, measures have been taken to relieve such restraint of the guide pin 5, and this measure will be explained using FIG. 5.4.

Figures 6 and 4 explain conventional measures to prevent misalignment between printed wiring boards, and Figure 6 shows a lamination adhesive mold with long radial guide holes. FIG. 4 is a perspective view showing a lamination adhesive mold in which a guide hole with a clearance is formed.

The lamination adhesive mold shown in FIG. 5 is an upper mold aA.

Guide holes 7 in the form of radial elongated holes are formed in the lower mold 6A, and guide pins 5 are formed by elongation of the printed wiring board 1 during heating.
This is so that the movement of the person is not restricted. However, since the thermal strain of the printed wiring board 1 does not necessarily occur radially, the direction of the thermal strain does not match the longitudinal direction of the guide hole 7, which is a radial elongated hole, and the movement of the guide pin 3 is not completely free. , will be restrained by the rA layer adhesive mold.

On the other hand, the laminated adhesive mold shown in FIG. However, if there is a difference in the magnitude of thermal strain of each printed wiring board 1 and the thickness direction of the multilayer printed wiring board is not uniform (this itself is also a cause of deviation). ), the guide pin 5 is tilted, and as a result, the guide pin 5 comes into contact with the edge of the guide hole 8, and the movement of the guide pin 5 is restrained, causing misalignment between each printed wiring board 1 after lamination and bonding. However, no matter what means was used, it was not possible to prevent the above-mentioned deviation.

[Purpose of the invention]

The present invention eliminates the above-mentioned drawbacks of the prior art and makes it possible to manufacture a multilayer printed wiring board with very little misalignment between printed wiring boards. The object of the present invention is to provide a mold for laminating and bonding multilayer printed wiring boards.

[Summary of the invention]

This invention. The structure of the lamination adhesive mold for a multilayer printed wiring board according to the above is such that guide holes are drilled in advance at predetermined positions. A laminate made by alternately stacking a plurality of printed wiring boards with metal foils attached to both sides of an insulating material and synthetic resin foils, and positioning each of the printed wiring boards by passing guide pins into the guide holes. of,
Up.

A mold for lamination bonding of a multilayer printed wiring board, which is loaded between the lower molds and applies pressure and heat to the laminated body from above and below to bond the printed wiring boards, thereby producing a multilayer printed wiring board. In type, above.

The material of the lower mold is made to be the same as the metal foil of the printed wiring board.

[Embodiments of the invention]

Before entering into the description of the embodiments, one basic matter related to the present invention will be explained.

FIG. 5 is a partially enlarged sectional view showing an example of a printed wiring board. In this FIG. 5, 12 in G6) relates to an insulator.

Made of 0.2fi thick glass cloth base epoxy resin.
One metal foil is applied to both sides of this glass cloth base epoxy resin 12. A copper foil 15 with a thickness of 0.055 m is attached.

Conventionally, a plurality of printed wiring boards 1 and synthetic resin foils 2 configured as described above are stacked alternately, and guide pins 3 are inserted into guide holes 1α.
Laminated body 5 (see Fig. 2) made of K1 steel upper mold 4. Lamination and adhesion was performed by applying pressure and heat using the lower mold 6 and the bolster, as described above.

Since the thermal strain of the printed wiring board 1 was larger than that of the upper and lower molds 4.6, "misalignment" occurred between the printed wiring boards 1.

According to the research conducted by the present inventors, the magnitude of the thermal strain of the printed wiring board 1 is determined by
The thermal expansion of the copper foil 15) is almost the same as that of the insulating material (glass cloth base epoxy resin 12 in the one in Figure 5) whose rigidity decreases when heated, and the thermal expansion of the printed wiring board is almost the same as that of the printed wiring board (15). It was found that it did not contribute.

The present invention was developed based on the above-mentioned findings, and the material of the upper and lower molds is made of the same material as the metal foil of the printed wiring board 1 instead of the conventional steel. In order to eliminate the difference in thermal strain between the mold and the printed wiring board 1, and to prevent the movement of the guide pins inserted into the printed wiring board 1 from being restricted by the upper and lower molds, each printing Between wiring boards 1”
This is to prevent "misalignment" from occurring.

Hereinafter, the present invention will be explained by examples.

FIG. 6 is a perspective view showing a mold for laminating and bonding a multilayer printed wiring board according to an embodiment of the present invention, and a laminate that is laminated and bonded using the mold.

In this FIG. 6, 1 indicates a guide hole 1 in a predetermined position.
α was drilled. A printed wiring board (see FIG. 5) comprising copper foil 15 as a metal foil attached to both sides of a glass cloth base epoxy resin 12 as an insulator.

2 is a synthetic resin foil.

Reference numeral 11 indicates an id pin made of the same material as the copper foil 15 of the printed wiring board 1, that is, copper. Reference numeral 9 has a guide hole 9α formed at a position into which the upper end of the guide pin 11 is fitted. A copper upper mold 10 made of the same material as the copper foil 15 of the printed wiring board 1 has a guide hole 10α formed at a position into which the lower end of the guide pin 11 is fitted. Like the upper mold 9, the lower mold is made of copper and is made of the same material as the copper foil 15 of the printed wiring board 1.

With the lamination adhesive mold configured in this way.

The operation of manufacturing a multilayer printed wiring board by pressurizing and heating a laminate of printed wiring boards will be described.

A plurality of printed wiring boards 1 and synthetic resin foils 2 are alternately stacked one on top of the other, and each printed wiring board 1 is positioned by passing guide pins 11 through guide holes 1α to form a laminate 5A. Then, in this state, the upper and lower end portions of the guide pin 11 are placed in the upper mold 9. Guide hole 9 (Z, 10
It is sandwiched between an upper mold 9 and a lower mold 10 so as to fit into α. This is placed on a press (not shown).
Load between the bolsters (heating plates) attached to the lower bed.

Here, when the press is turned on, electricity is applied to each of the bolsters to heat the laminate 5A, and when the temperature of the laminate 5A reaches a predetermined temperature, the ram of the press applies a predetermined pressure to the laminate 5A. loaded. The printed wiring board 1 is thermally strained by the heating, and the guide pins 11 inserted into the guide holes 1α of the printed wiring board 1 are moved.

Upper and lower molds 9.10 also. Since the thermal strain is almost the same as that of the printed wiring board 1, there is no difference in thermal strain between the printed wiring board 1 and the upper and lower molds 9 and 10, and the guide pin 1
1 is not restricted by the upper and lower molds 9° and 10.

Then, after a predetermined period of time has elapsed, the pressure and heat are removed, the lamination adhesion is completed, and the ram is raised. The head of the guide pin 11 is struck, causing the guide pin 11 to fall downward, resulting in a desired multilayer printed wiring board.

According to the embodiment described above, the upper mold 9. The lower mold 10 is made of the same material as the copper foil 15 that is the metal foil of the printed wiring board 1, and the upper mold 9. Since the difference in thermal strain between the lower mold 10 and the printed wiring board 1 is eliminated, the guide pin 1 inserted into the laminate 5A is removed when the laminate 5A is bonded.
1 movement is the upper mold 9. Since it is not constrained by the lower mold 10, it has the effect that defects in multilayer printed wiring boards that occur due to "misalignment" between printed wiring boards in conventional products can be significantly reduced.

A specific example will be explained.

In the printed wiring board 1, copper foil 15 (thickness 0.055+m) was attached to both sides of a glass cloth base epoxy resin 12 (thickness 0.2 tone). The laminate 5A includes a synthetic resin foil 2 having a thickness of 0.1 m and a size of 500 m square between the five printed wiring boards 1. It is made by laminating two sheets each. Guide pin 11
has an outer diameter of 15 knots, a length of 25 knots, and is made of copper. Upper mold9. The lower mold 10 has a plate thickness of 20 sections.

The size is 750w+m square, and the material is copper.

This laminate 5A is molded into the upper mold 9 described above. When laminated and bonded using the lower mold 10, the "misalignment" between each printed wiring board 1 was 0.02 mm (0.02 mm when using the conventional steel upper mold 4 and lower mold 5). .1 mn).

Note that in this embodiment, a case where copper foil 16 is attached as the metal foil of printed wiring board 1 has been described, but copper foil 1
When laminating and adhering a printed wiring board with other metal foil attached instead of 5, the upper and lower molds should be made of the same material as the metal, or one with a coefficient of thermal expansion similar to that of the metal. Just do it. For example, if the metal foil is aluminum foil, the material of the upper and lower molds may be aluminum.

Furthermore, the material of the guide pin 11 used in the lamination adhesive mold of this embodiment was copper, which is the same as the metal foil of the printed wiring board 1, but the outer diameter of the guide pin is small, and the guide pin and guide hole during heating are Since the difference in thermal strain between
However, if the material of the guide pin and the material of the metal foil are made the same, there will be no difference in thermal strain between the guide pin and the guide hole during heating, and the guide pin will not tilt.
The "deviation" can be further reduced.

〔Effect of the invention〕

As described above in detail, according to the present invention, it is possible to manufacture a multilayer printed wiring board with significantly less misalignment between printed wiring boards. A mold for laminating and bonding a multilayer printed wiring board can be provided.

[Brief explanation of the drawing]

1.2 is for explaining a conventional method of manufacturing a multilayer printed wiring board, and FIG. Perspective view showing the material and guide pins of the multilayer printed wiring board, 2nd
The figure is a perspective view showing an example of a laminate and a lamination bonding mold for pressurizing the laminate, and FIG. This has been done for a long time. FIG. 5 explains measures to prevent misalignment between printed wiring boards. FIG. 4 is a perspective view showing a lamination adhesive mold in which a radially long guide hole is bored, FIG. 4 is a perspective view showing a lamination adhesive mold in which a guide hole with a clearance is bored, and FIG.
FIG. 6 is a partially enlarged cross-sectional view showing an example of a printed wiring board, and FIG. 6 is a perspective view showing a mold for laminating and bonding a multilayer printed wiring board according to an embodiment of the present invention, and a laminate that is laminated and bonded using the mold. It is a diagram. DESCRIPTION OF SYMBOLS 1... Printed wiring board, 1α... Guide hole, 2... Synthetic resin foil, 5A... Laminated body, 9... Upper mold, 10
...Lower mold. 11...Guide pin, 12...Glass cloth base epoxy resin, 15...Copper foil. Figure l Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. A guide hole was drilled at a predetermined position in advance. A laminate made by alternately stacking a plurality of printed wiring boards with metal foils attached to both sides of an insulating material and synthetic resin foils, and positioning each of the printed wiring boards by passing guide pins into the guide holes. is loaded between upper and lower molds, and pressure and heat are applied to this laminate from above and below to bond the printed wiring boards together to produce a multilayer printed wiring board. A mold for laminating a multilayer printed wiring board, characterized in that the upper and lower molds are made of the same material as the metal foil of the printed wiring board.