WO2019030825A1

WO2019030825A1 - Method for manufacturing multiwire wiring board, and multiwire wiring board

Info

Publication number: WO2019030825A1
Application number: PCT/JP2017/028784
Authority: WO
Inventors: 洋志山口
Original assignee: 日立化成株式会社
Priority date: 2017-08-08
Filing date: 2017-08-08
Publication date: 2019-02-14
Also published as: KR20200033874A; JP6935817B2; KR102404116B1; JPWO2019030825A1

Abstract

Provided is a method for manufacturing a multiwire wiring board, the method enabling efficient disposition of a wire wiring layer in the plate thickness direction of a wiring board. This method for manufacturing a multiwire wiring board is provided with: a step for disposing a metal foil on a dummy substrate; a step for providing an adhesive layer on the metal foil; a step for laying an insulation coated wire on the adhesive layer so as to form a prescribed pattern; a step for forming an insulation layer on the adhesive layer after the insulation coated wire has been laid; a step for disposing a metal foil on the insulation layer; and a step for removing the dummy substrate from the metal foil.

Description

Multi-wire wiring board manufacturing method and multi-wire wiring board

The present invention relates to a method of manufacturing a multi-wire wiring board, and a multi-wire wiring board.

Patent Document 1 and Patent Document 2 disclose multi-wire wiring boards in which wires coated with a polyimide resin are wired on a substrate to increase the wiring density. In this multi-wire wiring board, from the viewpoint of efficiently manufacturing the wiring board and from the viewpoint of suppressing the warpage of the wiring board caused by the imbalance of internal stress, both surfaces of the central board for wiring are substantially equally A wiring board is formed such that a wiring board is formed into a single unit by forming a wire wiring and having two wired wiring layers (wire wiring layers). A plurality of wiring boards of one unit are combined to form a multilayer, or a wiring board of one unit is combined to another inner layer circuit forming substrate to form a multilayer.

JP, 2015-179833, A Unexamined-Japanese-Patent No. 2011-155045 Japanese Patent Publication No. 45-21434

In the multi-wire wiring boards described in Patent Documents 1 and 2, the wiring boards provided with the wire wiring layers on both sides of the central substrate constitute one unit, and are combined to form a multilayer. However, in this configuration, since two wire wiring layers are provided on the wiring board of one unit, for example, when manufacturing a multi-wire wiring board requiring three wire wiring layers, the wiring board of one unit is two. Although the one wire wiring layer is not used among them, as a whole, the multi-wire wiring board becomes unnecessarily thick. Similarly, even if one wire wiring layer is sufficient, one unit wiring board provided with two wire wiring layers is required as the minimum unit, and one wire wiring layer among them is not used. The multi-wire wiring board becomes unnecessarily thick. On the other hand, in order to avoid the above-mentioned point, a manufacturing method in which an unnecessary wire wiring layer is not provided on one side of the central substrate is also conceivable. However, in this case, since the wire wiring layer is provided only on one side of the central substrate, the force in the stacking direction of the manufactured multi-wire wiring board may become unbalanced and warpage may occur. Alternatively, since a configuration that does not generate warpage is separately provided, the manufacturing method may be complicated.

An object of the present invention is to provide a method of manufacturing a multi-wire wiring board capable of efficiently arranging a wire wiring layer in the thickness direction of the wiring board, and a multi-wire wiring board.

The present invention relates, as one aspect thereof, to a method of manufacturing a multi-wire wiring board. In the method of manufacturing the multi-wire wiring board, the step of disposing the first metal foil on the dummy substrate, the step of providing the adhesive layer on the first metal foil, and the step of providing the insulation coated wire on the adhesive layer The steps of wiring to form a pattern, forming an insulation layer on the adhesive layer after laying out the insulation coated wire, disposing a second metal foil on the insulation layer, and Removing the dummy substrate from the metal foil of

In the above method for manufacturing a multi-wire wiring board, a dummy substrate is used to produce a multi-wire wiring board having a single layer wire wiring layer (wiring pattern of insulation coated wire), and this dummy substrate is finally used. Is supposed to be removed. In this case, since the dummy substrate is finally removed, the multi-wire wiring board is unlikely to warp or the like even without adopting a configuration in which the wire wiring layers are provided on both sides of the central substrate, and has a single layer wire wiring layer. A multi-wire wiring board can be manufactured, and a multi-wire wiring board capable of efficiently arranging a wire wiring layer in the thickness direction of the wiring board can be easily manufactured. Further, in this manufacturing method, a predetermined strength is secured by the dummy substrate to be finally removed and the first metal foil disposed thereon, and the insulation coated wire is wired in a flat state on these bases. can do. For this reason, rattling and the like when laying the insulation coated wire in the adhesive layer is suppressed by these metal foils and the like, the layability is stabilized, the reliability of the layability of the insulation coated wire, the productivity improvement, and the high density Wiring becomes possible. Moreover, in this manufacturing method, since the formation of the inner layer circuit before wire wiring becomes unnecessary as in the prior art, the production lead time can also be shortened. Furthermore, since wiring is possible without being influenced by the copper foil thickness and circuit pattern of the inner layer circuit as in the prior art, a multi-wire wiring board with stable characteristic impedance can be obtained, and in particular, the wire diameter of the insulation coated wire is Even when the diameter is reduced, the characteristic impedance can be easily controlled. In addition, "wiring" (wiring) used here means making an insulation coating wire hang on the layers, such as a contact bonding layer, and making it adhere to the said layer.

In the above method of manufacturing a multi-wire wiring board, in the step of arranging the first metal foil, in the step of arranging the first metal foil on the dummy substrate via the third metal foil and removing the dummy substrate , And the third metal foil may be peeled off from the first metal foil. In this case, the third metal foil can further improve the layability such as the draw speed of the insulation coated wire and the certainty of the lay wire, and the third metal foil is peeled off in the final stage. The thickness of the multi-wire wiring board can be reduced.

In the method for manufacturing a multi-wire wiring board described above, the wire diameter of the insulation coated wire may be 140 μm or less, and the thickness of the third metal foil may be 50 μm or more. In this case, when the insulation coated wire is laid on the adhesive layer, the metal foil disposed on the lower side has a predetermined strength or more, so the wire laying speed of the insulation coated wire is increased. It is also possible to carry out secure wiring. In particular, when the insulation coated wire is laid on the adhesive layer by ultrasonic bonding in the step of laying, if the foundation is not firmly stabilized, rattling occurs and reliable bonding can not be achieved, so the strength of the foundation In some cases, it is necessary to reduce the laying speed. However, by providing the metal foil of the above-described strength (thickness) on the lower side, the insulation coated wire can be more reliably wired to the adhesive layer even in ultrasonic bonding. In the above case, the thickness of the third metal foil may be thicker than that of the first metal foil, and also in this case, the same effect can be obtained.

In the method of manufacturing a multi-wire wiring board described above, in the step of arranging the first metal foil, the first metal foil and the third metal foil are integrated, and mutually removable metal foils are formed on the dummy substrate. It may be arranged. In this case, since the first and third metal foils are integrated and peelable metal foils are used, the process of disposing the first and third metal foils on the dummy substrate can be simplified. In addition, as peelable metal foil, although peelable copper foil can be mentioned, for example, it is not limited to this.

In the above method of manufacturing a multi-wire wiring board, the dummy substrate has a surface area larger than that of the first metal foil, and in the step of disposing the first metal foil, laminating the insulating prepreg so as to cover the first metal foil. Then, the insulating prepreg may be adhered to the edge of the dummy substrate, whereby the first metal foil may be temporarily fixed on the dummy substrate, and in the step of providing the adhesive layer, the first metal foil of An adhesive layer may be laminated on top. In this case, the first metal foil can be securely temporarily fixed to the dummy substrate by the insulating prepreg, and when removing the dummy substrate, the dummy substrate can be easily removed by cutting off part of the insulating prepreg or the like. It becomes.

In the method of manufacturing a multi-wire wiring board described above, the adhesive layer is formed of an adhesive sheet containing a thermosetting or photocurable adhesive material, and in the step of laying out the wire, wire bonding of the insulation coated wire is carried out. The sheet may be heat set or light set, and the insulation coated wire may be fixed to the adhesive sheet with at least a part of the insulation coated wire embedded in the adhesive sheet. In this case, the wire laying operation of the insulation coated wire and the fixing operation to the adhesive layer can be easily performed.

In addition, even if the multi-wire wiring board manufactured by any of the multi-wire wiring board manufacturing methods described above is used as one unit, even-numbered units or odd-numbered units are stacked to form a multilayer multi-wiring wiring board of multilayer units. Good. In this case, since the multi-wire wiring board consisting of a single layer wire wiring layer becomes one unit, it is a multi-layer multi-wiring wiring board consisting of even units or a multi-layer multi-wiring wiring board consisting of odd units It becomes easy to assemble (design). Moreover, since it can comprise in this way, it becomes possible to obtain the multilayer multi wire wiring board which arrange | positioned the wire wiring layer efficiently in the board thickness direction of a wiring board.

The present invention relates, in another aspect, to a multi-wire wiring board. This multi-wire wiring board includes an insulation covering wire arranged in a predetermined pattern, an adhesion fixing layer in which at least a part of the insulation covering wire is embedded and the insulation covering wire is fixed by an adhesive, and an adhesion fixing layer An insulating layer covering the insulation coated wire together with the adhesive fixing layer, and first and second conductor layers provided on both sides of the laminate including the adhesive fixing layer and the insulating layer, Each of the two conductor layers is composed of an independent metal foil. In this case, as described above, a multi-wire wiring board having a single layer wire wiring layer can be manufactured, and a multi-wire wiring board capable of efficiently arranging the wire wiring layers can be obtained. In addition, since the wiring substrate is finally removed, it is possible to suppress warping of the multi-wire wiring board. The term "independent metal foil" as used herein means that metal foil attached to (or subordinate to) a substrate such as a central substrate with metal foil is excluded.

In the multi-wire wiring board described above, at least one of the first and second conductor layers may have a thickness of 10 μm or less. In this case, it is possible to obtain a thinner multi-wire wiring board than in the prior art.

Alternatively, any multi-wire wiring board described above may be used as one unit, and an even number of units or an odd number of units may be stacked to form a multilayer multi-wiring wiring board of a multilayer unit. In this case, since the multi-wire wiring board consisting of a single layer wire wiring layer becomes one unit, it is a multi-layer multi-wiring wiring board consisting of even units or a multi-layer multi-wiring wiring board consisting of odd units It becomes easy to assemble (design). In addition, since a single layer wire wiring layer can be configured as a basic unit, it is possible to obtain a multi-wire wiring board in which the wire wiring layers are efficiently arranged in the thickness direction of the wiring board.

According to the present invention, the thickness of the multi-wire wiring board can be reduced by efficiently arranging the wire wiring layers in the board thickness direction of the wiring board.

FIG. 1 is a cross-sectional view showing the configuration of a multi-wire wiring board according to an embodiment of the present invention. FIG. 2 is a sectional view sequentially showing a method for manufacturing the multi-wire wiring board shown in FIG. FIG. 3: is a figure which shows typically the operation | work which wires an insulation coating wire to an adhesive layer at the wiring process shown in FIG. FIG. 4 is a cross-sectional view showing a multilayer multi-wire wiring board in which three units of the multi-wire wiring board shown in FIG. 1 are stacked.

Hereinafter, a multi-wire wiring board and a method for manufacturing the multi-wire wiring board according to the present invention will be described with reference to the drawings. In the description, the same reference numeral may be used for the same element or an element having the same function, and the overlapping description will be omitted.

First, a multi-wire wiring board manufactured by the manufacturing method according to the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view showing the configuration of a multi-wire wiring board according to an embodiment of the present invention. As shown in FIG. 1, the multi-wire wiring board 1 includes an insulation coated wire 10, an adhesive fixing layer 11, an insulating layer 12, an underlay layer 13, a first conductor layer 14, and a second conductor layer 15. Is configured.

The insulation coated wire 10 is made of a conductive material such as copper and functions as a signal wire, the wire core wire 16 which functions as a signal wire, the insulating layer 17 for insulating the wire core wire 16 and the insulating layer 17 are easy to adhere to the adhesive fixing layer 11 And a wire bonding layer 18 for making the The insulation coated wire 10 is wired on the adhesive fixing layer 11 so as to have a predetermined pattern according to the design, and forms a single-layer wire wiring layer in the thickness direction of the wiring board. Since the insulation coating wire 10 is a wire whose insulation property is secured by the insulation layer 17 or the like, it is possible to adopt an arrangement in which the respective wires cross each other at the time of wiring so as to have a predetermined pattern. The wiring density can be increased by increasing the capacity of the Moreover, since the wire diameter of the insulation coating wire 10 is a small diameter of 140 micrometers or less, high-density-ization of wiring can be achieved also from this point. In addition, although the insulating layer 17 and the wire bonding layer 18 of the insulation coating wire 10 can be comprised, for example from a polyimide resin, a polyamide imide resin, or a fluorine resin, it is not limited to these and needs insulating property or adhesiveness. Other materials may be used as long as they perform the above functions.

The adhesive fixing layer 11 is a layer in which at least a portion of the lower part of the patterned insulation coated wire 10 is embedded therein to fix the insulation coated wire 10 with an adhesive. The adhesive fixing layer 11 is, for example, a thermosetting sheet of an adhesive sheet containing a thermosetting adhesive material, and the insulation coated wire 10 is laid on the adhesive sheet before curing, and the adhesive sheet is thermally cured after the laying. Then, the insulation coated wire 10 is fixed. For example, a thermosetting adhesive sheet containing a polyamideimide resin can be used as the thermal adhesive sheet for wiring. As the adhesive fixing layer 11, an adhesive sheet containing a photocurable adhesive material may be used instead of the thermosetting adhesive material or together with the thermosetting adhesive material. For example, the thickness of the adhesive fixing layer 11 is in the range of 70 μm to 150 μm.

The insulating layer 12 is a layer which is laminated on the adhesive fixing layer 11 and covers the insulating coated wire 10 together with the adhesive fixing layer 11. As the insulating layer 12, for example, an insulating prepreg used in a general printed wiring board can be used. For example, the thickness of the insulating layer 12 is in the range of 110 μm to 170 μm.

The underlay layer 13 is a layer laminated on the side opposite to the insulating layer 12 of the adhesive fixing layer 11. The underlay layer 3 can be made of an insulating prepreg in the same manner as the insulating layer 12. The underlay layer 13 has, for example, a thickness in the range of 45 μm to 85 μm. Note that, in the multi-wire wiring board 1, a configuration in which the underlay layer 13 is removed may be employed. In this case, the first conductor layer 14 is formed on the surface of the adhesive fixing layer 11 opposite to the insulating layer 12. May be provided directly.

The first conductor layer 14 is disposed on one side (the lower side in the drawing) of the adhesive fixing layer 11 via an underlay layer 13 which is an insulating prepreg. The second conductor layer 15 is disposed on the other side (upper side in the drawing) of the insulating layer 12. The first and second conductor layers 14 and 15 are layers obtained by processing a metal foil such as copper foil into a predetermined pattern by etching or the like, and can be used as a shield layer, for example. The first and second conductor layers 14 and 15 may be used as a power source, a ground layer, or a signal layer. The thickness of the first and second conductor layers 14 and 15 can be, for example, in the range of 5 to 15 μm, more preferably 9 to 12 μm, and the thickness can be further reduced by setting the thickness to 10 μm or less. It is possible to Each of the first and second conductor layers 14 and 15 is not made of copper foil attached to a conventional copper-clad laminate, but is made of an independent metal foil.

Since the multi-wire wiring board 1 having such a configuration has a single-layer wire wiring layer, the multi-wire wiring board 1 is a single unit, and it is a multi-layer multi-layered multi-layer consisting of either an even number unit or an odd number unit. Even the wire wiring board 30 (see FIG. 4; details will be described later) can be easily configured.

Next, a method of manufacturing the multi-wire wiring board 1 having the above-described configuration will be described with reference to FIG. FIG. 2 is a cross-sectional view showing a method for manufacturing the multi-wire wiring board shown in FIG.

First, as shown in FIG. 2A, the dummy substrate 26 is prepared, and the metal foil 27 (third metal foil) and the metal foil 24 (first metal foil) to be a conductor layer above the dummy substrate 26 are prepared. And in order. The dummy substrate 26 can be, for example, a laminated board having copper foils attached to both sides. Further, although the metal foil 27 and the metal foil 24 may be formed of separate members, the metal foils 24 and 27 are integrated, and the metal foil 27 and the metal foil 24 are configured of metal foils that can be separated from each other by a separation layer provided therebetween. It may be done. As such an integral-type metal foil, a peelable copper foil can be mentioned, for example. The dummy substrate 26 is configured such that its surface area is larger than that of each of the metal foils 24 and 27, and a workpiece having a size of about 500 mm × 600 mm can be used.

When the metal foils 24 and 27 are disposed on the dummy substrate 26, next, a prepreg to be the underlay layer 23 is laminated so as to cover the metal foil 24. Then, the prepreg is adhered to the edge of the dummy substrate 26 by heating and pressurizing the prepreg, whereby the metal foils 24 and 27 are temporarily fixed to the dummy substrate 26. The prepreg used here is a sheet-like one in which the reinforcing material is impregnated with the insulating resin to be in a semi-cured state, or a sheet-like one in this semi-cured state, by lamination integration by heating and pressure, etc. It refers to a hardened insulating layer. The prepreg used in the present embodiment is formed of a general-purpose base material. As the reinforcing material of the general-purpose base material, paper or woven fabric or non-woven fabric using glass fiber or aramid fiber can be used. Further, as the insulating resin, a thermosetting resin such as an epoxy resin, a polyimide resin, or a phenol resin can be used. As such a general-purpose substrate, for example, as epoxy type, FR-4 material (Flame Retardant Type 4) or FR-5 material (Flame Retardant Type 5) is mentioned, and as polyimide type, GPY material is mentioned Be

Subsequently, as shown in FIG. 2B, the adhesive layer 21 is laminated on the metal foil 24 through the prepreg that has been heated and pressurized. As the adhesive layer 21, for example, an adhesive sheet containing a thermosetting adhesive material can be used, and this adhesive sheet is laminated. As the adhesive layer 21, an adhesive sheet containing a photocurable adhesive material may be used. After that, the insulation coated wire 10 is wired on the adhesive layer 21 by ultrasonic bonding with a wire control device of numerical control to form a predetermined wiring pattern (see FIG. 3). The bonding conditions by ultrasonic bonding may be, for example, an ultrasonic output of 25 kHz and a wire-drawing speed of between 20 mm / sec and 30 mm / sec. In addition, as shown in FIG. 3, during this wiring, a portion (lower portion) of the insulation coated wire 10 is pushed so as to be embedded in the adhesive layer 21, but the base portion of the adhesive layer 21 is not firm. In addition, looseness or the like occurs during the laying operation, and it is necessary to lay the wire while lowering the laying speed by the laying machine head H of the laying device. However, in the present embodiment, since the metal foil 27 thicker than the metal foil 24 to be the conductor layer 14 is provided below the adhesive layer 21, the metal foil 27 can suppress rattling during wiring. It has become. The thickness of the metal foil 27 is preferably 50 μm or more (for example, 70 μm or 80 μm) as described later, from the viewpoint of the workability and the reliability of wire laying, but even if it is less than 50 μm laying It is possible to ensure wire laying, such as by making the speed slower depending on the form of the laying.

Subsequently, when the wire arrangement of the insulation coated wire 10 is finished, the adhesive layer 21 made of an adhesive sheet is cured to form an adhesive fixing layer. Thereby, the insulation coating wire 10 is fixed to the adhesive layer 21 (adhesive fixing layer 11) by the adhesive material. In the example described above, the adhesive layer 21 is provided through the prepreg, but the prepreg may be omitted if the metal foils 24, 27 etc. are temporarily fixed to the dummy substrate 26 by the adhesive layer 21 or the like. In this case, the adhesive layer 21 made of an adhesive sheet or the like is directly laminated on the metal foil 24.

Subsequently, after the insulation coated wire 10 is wired to the adhesive layer 21, as shown in FIG. 2C, the insulating layer 22 is laminated on the adhesive layer 21. As the insulating layer 22, a prepreg similar to that of the underlay layer 23 may be used. Then, a metal foil 25 (second metal foil) made of copper foil or the like is laminated on the insulating layer 22 and heated and pressurized to reliably bond the insulating layer 22 to the adhesive layer 21 and the metal foil 25. .

Subsequently, as shown in FIG. 2D, the workpiece for the wiring board is cut at positions L1 and L1 that are inside the both ends of the metal foils 24 and 27. By this cutting, the dummy substrate 26 is removed from the metal foils 24 and 27 temporarily fixed by the prepreg. In addition, the metal foil 27 which plays the function of mainly supporting the laying operation from below is peeled off from the metal foil 24.

Subsequently, the metal foils 24 and 25 are processed by etching or the like to form first and second conductor layers 14 and 15, as shown in FIG. 2 (e). In addition, since the first and second conductor layers 14 and 15 are subjected to etching treatment and the like, their surfaces are roughened, and other members used in multilayering (prepreg used for connection Etc.) or resin materials etc. Thus, the multi-wire wiring board 1 having a single layer wire wiring layer can be obtained.

As described above, in the method for manufacturing a multi-wire wiring board according to the present embodiment, the multi-wire wiring board 1 having a single layer wire wiring layer (wiring pattern of the insulation coated wire 10) is manufactured using the dummy substrate 26; Moreover, the dummy substrate 26 is finally removed. As described above, since the dummy substrate 26 is finally removed, the multi-wire wiring board 1 is unlikely to be warped or the like without adopting the conventional configuration in which the wire wiring layers are provided on both sides of the central substrate. The multi-wire wiring board 1 having the wiring layer can be manufactured, and the multi-wire wiring board capable of efficiently arranging the wire wiring layer in the thickness direction of the wiring board can be easily manufactured. Further, in this manufacturing method, a predetermined strength is secured by the dummy substrate 26 to be finally removed and the metal foils 24 and 27 disposed thereon, and the insulation coated wire 10 is flatly formed on these bases. It can be laid out. Therefore, rattling and the like when laying the insulation coated wire 10 on the adhesive layer 21 is suppressed by the metal foil 27 etc., and the layability is stabilized, and the reliability of the layability of the insulation coated wire 10 and the productivity are improved. And high density wiring becomes possible. Moreover, in this manufacturing method, since the formation of the inner layer circuit before wire wiring becomes unnecessary as in the prior art, the production lead time can also be shortened. Furthermore, since wiring can be performed without being affected by the copper foil thickness or circuit pattern of the inner layer circuit as in the prior art, a multi-wire wiring board with stable characteristic impedance can be obtained. In particular, the wire diameter of the insulation coated wire 10 The characteristic impedance can be easily controlled even when the diameter is reduced.

In the method of manufacturing a multi-wire wiring board according to the present embodiment, the metal foil 24 is disposed on the dummy substrate via the metal foil 27 and the metal foil 27 is peeled off from the metal foil 24 in the final stage. For this reason, the metal foil 27 can further improve the laying property such as the laying speed of the insulation coated wire 10 or the certainty of the laying line, and at the same time the multi-layer manufactured from peeling the metal foil 27 at the final stage. The thickness of the wire wiring board 1 can be reduced.

In the method for manufacturing a multi-wire wiring board according to the present embodiment, the wire diameter of the insulation coated wire 10 may be 140 μm or less, and the thickness of the metal foil 27 may be 50 μm or more. In this case, when the insulation coated wire 10 is laid on the adhesive layer 21, the metal foil 27 disposed on the lower side has a predetermined strength. It is possible to execute secure wiring at the earliest. In particular, when the insulation coated wire 10 is laid on the adhesive layer 21 by ultrasonic bonding in the step of laying the wire, if the foundation is not firmly stabilized, rattling occurs and reliable bonding can not be achieved. The speed of wire laying can not but be reduced depending on the strength of the However, by providing the metal foil 27 having the above-described strength (thickness) on the lower side, the insulation coated wire 10 can be more reliably wired to the adhesive layer 21 even in ultrasonic bonding. In the above case, the thickness of the metal foil 27 may be thicker than that of the metal foil 24. Also in this case, the same effect can be obtained.

In the method for manufacturing a multi-wire wiring board according to the present embodiment, in the step of arranging the metal foils 24, metal foils 24 and 27 may be integrated and metal foils which can be separated from each other may be arranged on the dummy substrate 26. . In this case, since the metal foils 24 and 27 are integrated and peelable metal foils are used, the process of arranging the metal foils 24 and 27 can be simplified.

In the method of manufacturing a multi-wire wiring board according to the present embodiment, the surface area of the dummy substrate 26 is larger than that of each of the metal foils 24 and 27, and the step of arranging the metal foil 24 insulates the metal foils 24 and 27. The prepregs may be stacked to bond the insulating prepreg to the edge of the dummy substrate 26, whereby the metal foils 24 and 27 may be temporarily fixed on the dummy substrate 26. Further, in the step of arranging the adhesive layer 21, the adhesive layer 21 may be laminated on the metal foil 24 through the insulating prepreg. In this case, the metal foils 24 and 27 can be securely temporarily fixed to the dummy substrate 26 by the insulating prepreg, and when removing the dummy substrate 26, the dummy substrate 26 can be easily removed by cutting off part of the insulating prepreg or the like. It becomes possible.

In the method for manufacturing a multi-wire wiring board according to the present embodiment, the adhesive layer 21 is formed of an adhesive sheet containing a thermosetting or photocurable adhesive material, and in the step of laying out the wire, the insulation coated wire 10 is clothed. After the wire bonding, the adhesive sheet may be heat-cured or light-cured, and the insulation-coated wire 10 may be fixed to the adhesive sheet in a state where a part of the insulation-coated wire 10 is embedded in the adhesive sheet. In this case, the wire laying operation of the insulation coated wire 10 and the fixing operation to the adhesive layer 21 can be easily performed.

Further, in the multi-wire wiring board 1 according to the present embodiment, a multi-wire wiring board having a single layer wire wiring layer can be manufactured, and a multi-wire wiring layer can be efficiently arranged in the thickness direction of the wiring board. It becomes possible to obtain a wire wiring board. In addition, since the wiring substrate is finally removed, it is possible to suppress warping of the multi-wire wiring board.

Here, regarding an example in which a multi-wire wiring board manufactured by the above-described method for manufacturing a multi-wire wiring board is taken as one unit, and an odd number (three in the present embodiment) of units are stacked to form a wiring board of a multilayer unit. This will be described with reference to FIG. FIG. 4 is a cross-sectional view of a multilayer multi-wire wiring board 30 in which three units of the multi-wire wiring board shown in FIG. 1 are stacked.

As shown in FIG. 4, a multilayer multi-wire wiring board 30 having a plurality of units includes three multi-wire wiring boards 1 (units U1, U2, U3) and an insulating layer 31 stacked above the unit U1. Two insulating layers 32 and a copper-clad laminate 33 disposed between unit U1 and unit U2 and connecting both units, and two insulating layers 34 disposed between unit U2 and unit U3 and connecting both units And a copper-clad laminate 35, and an insulating layer 36 stacked below the unit U3. In the multilayer multi-wire wiring board 30, each insulating

layer

31, 32, 34 and 36 is made of, for example, an insulating prepreg, and the copper foil of the copper-clad

laminates

33 and 35 functions as an inner layer circuit. Can. In addition, two types of through

holes

37 and 38 are provided in the multilayer multi-wire wiring board 30, and the through holes 37 are used to connect the insulation coated wire 10 and the surface circuit 39 by metal plating. The holes 38 connect the ground layer and the surface circuit 39 by metal plating.

As described above, since the multi-wire wiring board 1 according to the present embodiment is formed of a single-layer wire wiring layer, when forming the multilayer multi-wire wiring board, the number of even units and odd units is not It is possible to cope with any one, and it is possible to provide a multi-wire wiring board capable of efficiently arranging the wire wiring layer according to the design.

As mentioned above, although the embodiment of the present invention has been described in detail, the present invention is not limited to the above embodiment and can be applied to various embodiments. For example, in the above embodiment, an example of a multi-wire wiring board in which an odd number (3 units) of multi-wire wiring boards formed of single-layer wire wiring layers is stacked is shown. The wiring board may be configured.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited to these examples. In the following examples, the relationship between the thickness of the metal foil and the change in the wire speed when the metal foil was disposed on the dummy substrate to wire the insulation coated wire was examined.

Example 1
First, as shown in FIG. 2A, a copper-clad laminate (manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-I-671) is prepared as the dummy substrate 26, and metal foils 24 and 27 are formed on the surface. A corresponding peelable copper foil (manufactured by Furukawa Electric Co., Ltd., trade name "F-DP foil (very thin foil)") was disposed. Among the peelable copper foils, the thickness of the metal foil 27 peeled off in the later step was 70 μm, and the thickness of the metal foil 24 remaining after peeling was 9 μm. Moreover, the surface area of this peelable copper foil was smaller than that of the copper clad laminate. The copper-clad laminate as the dummy substrate 26 had a work size of 500 mm × 600 mm. Next, a prepreg (Hitachi Chemical Co., Ltd., trade name: GIA-671N) which is the underlay layer 23 was laminated thereon so as to cover the peelable copper foil. Thereafter, the prepreg was heated and pressurized to adhere the prepreg to the edge of the copper-clad laminate and to temporarily fix the pilled copper foil to the copper-clad laminate.

Next, as shown in FIG. 2 (b), a wire bonding sheet (product name: HPAI, manufactured by Hitachi Chemical Co., Ltd.) corresponding to the adhesive layer 21 was laminated on the prepreg. The wire bonding sheet was made of a thermosetting adhesive material. And the insulation coating wire 10 was wired so that it might become a predetermined pattern on the adhesive sheet for wiring. The wire laying speed at this time could be 20 mm / sec. Thereafter, when the wire arrangement of the insulation coated wire 10 was completed, a heat treatment was performed at 200 ° C. for 90 minutes to cure the wire bonding sheet.

Next, as shown in FIG. 2 (c), a prepreg (Hitachi Chemical Co., Ltd., trade name: GIA-671N) corresponding to the insulating layer 22 and a metal foil 25 are formed on the cured adhesive sheet for wiring. A copper foil (Mitsui Metal Mining Co., Ltd., trade name: MW-G, thickness 18 μm) corresponding to the above was laminated, heated and pressed. Thereby, the copper foil and the adhesive sheet for wiring were adhered by the prepreg.

Next, as shown in FIG. 2D, the positions L1 and L1 slightly inside the end of the peelable copper foil are cut, the dummy substrate 26 is removed, and the portion corresponding to the metal foil 27 is made of the peelable copper foil. It peeled off. Thereafter, the metal foils 24 and 25 are etched away to form a predetermined conductor pattern, whereby a multi-wire wiring board 1 shown in FIG. 2 (e) is obtained. The wiring speed at the time of wiring the insulation coated wire 10 in this multi-wire wiring board 1 is 30 mm / sec as described above, and even if wiring is performed at this set speed, the insulation coated wire 10 is used for wiring. It was possible to securely lay out the adhesive sheet.

(Example 2)
Next, a multi-wire wiring layer is prepared in the same manner as in Example 1, except that among the peelable copper foils corresponding to the metal foils 24 and 27, a copper foil having a thickness of 35 μm is used. Was produced. When laying the insulation coating wire 10 in the multi-wire wiring board 1, the base has a slight rattling speed, and the laying speed is 21 mm / sec. The wire 10 could be reliably laid on the adhesive sheet for laying wire.

(Example 3)
Next, a multi-wire wiring layer is prepared in the same manner as in Example 1, except that among the peelable copper foils corresponding to the metal foils 24 and 27, a copper foil having a thickness of 18 μm is used. Was produced. When laying the insulation coating wire 10 in this multi-wire wiring board 1, the laying speed is 8 mm / sec because the base is rattling, and even if the setting speed is performed at this setting speed, the insulation coating wire 10 was able to be reliably laid out on the adhesive sheet for laying wire.

Table 1 below shows the test results of the thickness of the metal foil 27 and the wire laying speed of the insulation coated wire 10 in Examples 1 to 3. As shown in Table 1, when the thickness of the metal foil 27 was 50 μm or more, the laying speed could be as fast as 30 mm / sec. On the other hand, if the thickness of the metal foil 27 is less than 50 μm, it is difficult to reliably perform the wire laying operation unless the wire laying speed to be set is slightly reduced, but the wire laying operation for the insulation coated wire is surely performed. Was possible.

As mentioned above, according to the manufacturing method shown in FIG. 2, it has confirmed that the multi-wire wiring board which has a wire-wiring layer of a single layer was easily producible.

The present invention can be applied to a multi-wire wiring board where it is desired to efficiently arrange a wire wiring layer in the thickness direction of the wiring board.

DESCRIPTION OF SYMBOLS 1 ... Multi-wire wiring board, 10 ... insulation coating wire, 11 ... adhesion fixing layer, 12 ... insulation layer, 13 ... underlay layer, 14 ... 1st conductor layer, 15 ... 2nd conductor layer, 16 ... wire core wire , 17: insulating layer, 18: wire adhesive layer, 21: adhesive layer, 22: insulating layer, 23: underlay layer, 24, 25, 27: metal foil, 26: dummy substrate, 30: multilayer multi-wire wiring board, 31, 32, 34, 36: Insulating layer, 33, 35: Copper-clad laminate, 39: Surface circuit, H: Wire machine head.

Claims

Placing a first metal foil on the dummy substrate;
Providing an adhesive layer on the first metal foil;
Laying an insulation coated wire on the adhesive layer in a predetermined pattern;
Forming an insulating layer on the adhesive layer after laying out the insulating coated wire;
Placing a second metal foil on the insulating layer;
Removing the dummy substrate from the first metal foil;
A method of manufacturing a multi-wire wiring board comprising:
In the step of arranging the first metal foil, the first metal foil is arranged on the dummy substrate via a third metal foil,
Removing the third metal foil from the first metal foil in the step of removing the dummy substrate;
A method of manufacturing a multi-wire wiring board according to claim 1.
The wire diameter of the insulation coated wire is 140 μm or less, and the thickness of the third metal foil is 50 μm or more.
The manufacturing method of the multi-wire wiring board of Claim 2.
The thickness of the third metal foil is thicker than the first metal foil,
The manufacturing method of the multi-wire wiring board of Claim 2 or 3.
In the step of arranging the first metal foil, the first metal foil and the third metal foil are integrated and metal foils which can be peeled off from each other are arranged on the dummy substrate.
A method of manufacturing a multi-wire wiring board according to any one of claims 2 to 4.
The dummy substrate has a surface area larger than that of the first metal foil,
In the step of arranging the first metal foil, an insulating prepreg is laminated so as to cover the first metal foil, and the insulating prepreg is adhered to the edge of the dummy substrate, whereby the first metal foil is made Temporarily fixed on the dummy substrate,
In the step of providing the adhesive layer, the adhesive layer is laminated on the first metal foil via the insulating prepreg.
A method of manufacturing a multi-wire wiring board according to any one of claims 1 to 5.
In the laying step, the insulation coated wire is laid on the adhesive layer by ultrasonic bonding.
A method of manufacturing a multi-wire wiring board according to any one of claims 1 to 6.
The adhesive layer is formed of an adhesive sheet containing a thermosetting or photocurable adhesive material,
In the laying step, after laying the insulation coated wire, the adhesive sheet is thermally cured or photocured, and at least a part of the insulation coated wire is embedded in the adhesive sheet. Fixed to the adhesive sheet,
A method of manufacturing a multi-wire wiring board according to any one of claims 1 to 7.
A wiring board of a multilayer unit is formed by stacking even units or odd units by using the multi-wire wiring board manufactured by the method for manufacturing a multi-wire wiring board according to any one of claims 1 to 8 as one unit. A method of manufacturing a multilayer multi-wire wiring board.
Insulation coated wire which is wired in a predetermined pattern;
An adhesive fixing layer in which at least a part of the insulation coated wire is embedded and the insulation coated wire is fixed by an adhesive;
An insulating layer laminated on the adhesive fixing layer and covering the insulating coated wire together with the adhesive fixing layer;
And first and second conductor layers provided on both sides of a laminate including the adhesive fixing layer and the insulating layer,
Each of the first and second conductor layers is composed of an independent metal foil,
Multi-wire wiring board.
At least one of the first and second conductor layers has a thickness of 10 μm or less.
The multi-wire wiring board according to claim 10.
A multilayer multi-wire wiring board comprising a multi-wire wiring board according to claim 10 or 11 as one unit, and an even number unit or an odd number of units stacked to form a wiring board of a multi-layer unit.