TW201922070A - Printed wiring substrate and manufacturing method thereof - Google Patents

Abstract

A printed wiring substrate, includes: a first wiring substrate having a first insulating layer, a first conductive layer, a second conductive layer, and first substrate deformed portions in which at least one of the first conductive layer and the second conductive layer is bent and deformed, the first insulating layer having a first main surface, a second main face opposite to the first main surface, and a first hole, the first conductive layer being formed on the first main surface, the second conductive layer being formed on the second main surface, the first conductive layer and the second conductive layer being bonded to each other through the first hole; and a second wiring substrate having a second insulating layer, a third conductive layer, a fourth conductive layer, and second substrate deformed portions in which at least one of the third conductive layer and the fourth conductive layer is bent and deformed, the second insulating layer having a third main surface, a fourth main face opposite to the third main surface, and a second hole, the third conductive layer being formed on the third main surface and being bonded to the second conductive layer, the fourth conductive layer being formed on the fourth main surface, the third conductive layer and the fourth conductive layer being bonded to each other through the second hole, the second wiring substrate being laminated on the first conductive layer.

Description

Printed wiring board and manufacturing method thereof

FIELD OF THE INVENTION The present invention relates to a printed wiring board and a method for manufacturing the same. The present invention claims priority based on Japanese Patent Application No. 2017-162583, filed in Japan on August 25, 2017, and incorporates its contents into the present invention.

BACKGROUND OF THE INVENTION In the manufacture of flexible printed wiring boards, the production of wiring boards in a roll form has many advantages in terms of productivity, quality, etc. compared to the method of producing in the shape of paper. The wiring board is configured in a roll shape, which is an end portion to which a paper-shaped wiring board is connected. As a technology for connecting wiring boards, there is an ultrasonic bonding technology (for example, refer to Patent Document 1). Ultrasonic bonding is a technique that produces a metal-to-metal bond by applying ultrasonic vibration to a metal material. The ultrasonic bonding method is different from the connection method using a bonding tape or an adhesive, and there is no intervening substance on the bonding surface. Ultrasonic bonding is different from the case where a resin is used, and it is also preferable for the heat treatment and heating time for curing the resin. The printed wiring board described in Patent Document 1 is a laminated board in which a metal foil is laminated on a resin layer by ultrasonic bonding. Prior technical literature Patent literature

[Patent Document 1] Japanese Patent Publication No. 5151313

Summary of the Invention Problems to be Solved by the Invention

In ultrasonic bonding, sufficient vibration must be applied to the bonding interface. However, in the printed wiring board described in Patent Document 1, since a resin layer exists between the metal foil to be bonded and the metal foil, it is difficult to transmit sufficient vibration to the bonding interface, and high bonding cannot be obtained at the bonding interface. strength.

It is an object of the present invention to provide a printed wiring board to which a wiring substrate is bonded with high bonding strength, and a method for manufacturing the same. Means to solve the problem

A printed wiring board according to the present invention includes a first wiring substrate and a second wiring substrate. The first wiring substrate includes a first main surface and a second main surface and a first main surface opposite to the first main surface. A first insulating layer of a hole portion, a first conductive layer formed on the first main surface, a second conductive layer formed on the second main surface and bonded to the first conductive layer through the first hole portion, and A first substrate deformed portion that bends and deforms at least one of the first conductive layer and the second conductive layer; the second wiring substrate is laminated on the first wiring substrate, and has a third main surface and a first main surface. A 4th main surface opposite to the 3 main surface and a second insulating layer of the second hole portion, a 3rd conductive layer formed on the 3rd main surface and bonded to the 2nd conductive layer, formed on the 4th main surface and passing through A fourth conductive layer connected to the third conductive layer by the second hole portion, and a second substrate deformed portion that bends and deforms at least one of the third conductive layer and the fourth conductive layer.

The fourth conductive layer is formed in a flat shape, and the third conductive layer is bent and deformed in the second hole portion in a direction close to the fourth conductive layer, and at least a part of the third conductive layer is joined to the fourth conductive layer, and the second substrate is deformed. One of the parts is a third deformed part, the second conductive layer is bent and deformed along the third deformed part and at least a part is joined to the third conductive layer, and one of the first substrate deformed parts is also a second deformed part. The first conductive layer is bent and deformed along the second deformed portion, and at least a part of the first conductive layer is joined to the second conductive layer, and one of the first substrate deformed portions may be the first deformed portion.

The second conductive layer is formed in a flat shape, the first conductive layer is bent and deformed in the first hole portion in a direction close to the second conductive layer, and at least a part of the first conductive layer is bonded to the second conductive layer, and the first substrate is deformed One of the parts is the first deformed part. The third conductive layer is formed into a flat shape. The fourth conductive layer is bent and deformed in the second hole portion in a direction close to the third conductive layer, and at least a part of the third conductive layer is conductive with the third conductive layer. Layer bonding is also possible, and one of the second substrate deformed portions, that is, the fourth deformed portion may be provided.

A method for manufacturing a printed wiring board according to a second aspect of the present invention includes: a first step, a second step, and the aforementioned first step: preparing a first wiring substrate, preparing a second wiring substrate, and laminating the first wiring substrate. Unlike the second wiring substrate, the first wiring substrate includes a first insulating layer, a first conductive layer formed on one side of the first insulating layer, that is, a first main surface, and the first insulating layer formed on the first insulating layer. The second conductive layer on the second main surface opposite to the first main surface; the second wiring board includes a second insulating layer, a third conductive layer formed on one side of the second insulating layer, that is, a third main surface, and formed The fourth conductive layer on the fourth main surface opposite to the third main surface of the second insulating layer; the second step: applying ultrasonic waves to the first wiring substrate and the second wiring substrate to perform In the second step, the first conductive layer is bonded to the second conductive layer, the second conductive layer is bonded to the third conductive layer, and the third conductive layer is bonded to the fourth conductive layer. A first hole portion is formed in the first insulating layer, and the first hole is formed. At least one of the electric layer and the second conductive layer is bent and deformed in a direction closer to the other, and the first conductive layer and the second conductive layer are joined through the first hole portion, and a second is formed on the second insulating layer. A hole portion, and at least one of the third conductive layer and the fourth conductive layer is bent and deformed in a direction close to the other, and the third conductive layer and the fourth conductive layer are joined via the second hole portion.

In the second step, by applying the ultrasonic waves and pressure from the first conductive layer, the third conductive layer is formed by being bent and deformed in the second hole portion in a direction close to the fourth conductive layer to form at least a portion. A third deformed portion joined to the fourth conductive layer is formed on the second conductive layer. The second deformed portion is bent and deformed along the third deformed portion and at least a part of the second deformed portion is joined to the third conductive layer. Conductive layer formation: The first deformed portion may be bent and deformed along the second deformed portion and at least a part of the first deformed portion may be joined to the second conductive layer.

In the second step, the ultrasonic wave and pressure are applied from the first conductive layer and the pressure is applied from the fourth conductive layer to form the first conductive layer in the first hole portion toward the first conductive layer. The first deformed portion in which the direction of the 2 conductive layer is bent and deformed and at least a portion is joined to the second conductive layer is formed on the fourth conductive layer by applying pressure from the fourth conductive layer: toward the inside of the second hole portion. The third deformed portion is bent and deformed in the direction of the third conductive layer, and at least a part of the fourth deformed portion is joined to the third conductive layer. Invention effect

According to the aforementioned aspect of the present invention, when the first wiring substrate and the second wiring substrate are bonded, the external force does not act on the bonding interface of the conductive layer through the insulating layer. For this reason, the strength of the bonding conductive layer can be increased. Therefore, the wiring substrate can be firmly bonded.

Forms used to implement the invention

Hereinafter, the present invention will be described with reference to the drawings based on suitable embodiments. In addition, the embodiments described below are examples for better understanding of the purpose of the invention, and the invention is not limited thereto unless otherwise specified. In addition, the drawings used in the following description may be enlarged and enlarged to make it easier to understand the features of the present invention, and are not limited to the dimensional ratios and the like of each constituent element as they are in practice. In addition, in order to easily understand the features of the present invention, there are omitted portions for convenience.

[First Embodiment] (Printed Wiring Board) A printed wiring board according to this embodiment includes a first wiring board having a first main surface and a second main surface and a second main surface opposite to the first main surface. A first insulating layer in a hole portion, a first conductive layer formed on the first main surface, a second conductive layer formed on the second main surface, and bonded to the first conductive layer through the first hole portion, And a first substrate deforming portion that bends and deforms at least one of the first conductive layer and the second conductive layer; and a second wiring substrate having a third main surface and a third main surface opposite to the third main surface. The second insulating layer of the 4 main surface and the second hole portion is formed on the third main surface and a third conductive layer bonded to the second conductive layer is formed on the fourth main surface and passes through the second hole. And a second substrate deforming portion that bends and deforms at least one of the third conductive layer and the fourth conductive layer, and the second wiring substrate is connected to the first conductive layer The wiring substrates are laminated together. The configuration of the printed wiring board 10 according to the first embodiment of the present invention will be described using FIG. 1. FIG. 1 is a cross-sectional view schematically showing a printed wiring board 10 according to the first embodiment. The plan view is viewed from a direction parallel to the thickness direction of the first wiring substrate 1 and the second wiring substrate 2.

As shown in FIG. 1, the printed wiring board 10 includes a first wiring substrate 1 and a second wiring substrate 2. At least a part of the first wiring substrate 1 and the second wiring substrate 2 are laminated. In the printed wiring board 10, an end region 1A of the first wiring substrate 1 and an end region 2A of the second wiring substrate 2 are overlapped. The end region 1A is a region including the end portion 1 a of the first wiring substrate 1. The end portion region 2A is a region including the end portion 2 a of the second wiring substrate 2.

The first wiring substrate 1 includes a first insulating layer 11, a first conductive layer 12, and a second conductive layer 13. The first insulating layer 11 is made of an insulating material. Examples of the insulating material include polyimide resin, PET (polyethylene terephthalate), PEN (polyethylene naphthalate), LCP (liquid crystal polymer) resin, and glass epoxy. The first insulating layer 11 may be a flexible substrate (flexible substrate). Fight

A first hole portion 31 is formed in the first insulating layer 11. The first hole portion 31 is formed through the first insulating layer 11 in the thickness direction. The inner shape (size) of the first hole portion 31 is formed to gradually decrease from the first main surface 11 a toward the second main surface 11 b. The first hole portion 31 is, for example, circular in a plan view.

The first conductive layer 12 is formed on the first main surface 11 a of the first insulating layer 11. The first main surface 11 a is one surface (the upper surface and the first surface in FIG. 1) of the first insulating layer 11. The second conductive layer 13 is formed on the second main surface 11 b of the first insulating layer 11. The second main surface 11 b is the other surface (the lower surface and the second surface in FIG. 1) of the first insulating layer 11. The first conductive layer 12 and the second conductive layer 13 are made of a conductive material such as copper or solder. The first conductive layer 12 and the second conductive body 13 are formed using, for example, a metal foil such as a copper foil. The first conductive layer 12 and the second conductive body 13 may be formed using a conductive paste containing metal particles such as silver and copper.

The second wiring board 2 includes a second insulating layer 21, a third conductive layer 22, and a fourth conductive layer 23. The second insulating layer 21 is made of an insulating material (described above). The second insulating layer 21 may be a flexible substrate (flexible substrate).

A second hole portion 32 is formed in the second insulating layer 21. The second hole portion 32 is formed through the second insulating layer 21 in the thickness direction. The internal shape size (size) of the second hole portion 32 is formed to gradually decrease from the third main surface 21a toward the fourth main surface 21b. The second hole portion 32 is, for example, circular in a plan view.

The third conductive layer 22 is formed on the third main surface 21 a of the second insulating layer 21. The third main surface 21 a is one surface (the upper surface and the first surface in FIG. 1) of the second insulating layer 21. The fourth conductive layer 23 is formed on the fourth main surface 21 b of the second insulating layer 21. The fourth main surface 21 b is the other surface (the lower surface and the second surface in FIG. 1) of the second insulating layer 21. The fourth conductive layer 23 is formed in a flat shape over the entire area along the fourth main surface 21b. The third conductive layer 22 and the fourth conductive layer 23 are formed using a conductive material such as copper or solder, for example, a metal foil such as a copper foil. The third conductive layer 22 and the fourth conductive layer 23 may be formed using a conductive paste containing metal particles such as silver and copper.

The third conductive layer 22 includes a third deformed portion 24 that is bent and deformed in a direction close to the fourth conductive layer 23. The third deformed portion 24 is formed in the second hole portion 32 along the inner surface of the second hole portion 32. The third deformation portion 24 is formed, for example, in a conical shape or a truncated cone shape in which the diameter gradually decreases from the third main surface 21 a toward the fourth main surface 21 b. The third deformed portion 24 is joined to the upper surface (opposing surface 23a) of the fourth conductive layer 23 in the vertex portion 24a. By bonding the third deformed portion 24 and the fourth conductive layer 23, the third conductive layer 22 and the fourth conductive layer 23 are bonded to each other via the second hole portion 32.

The second conductive layer 13 includes a second deformed portion 15 that is bent and deformed in a direction close to the third conductive layer 22. The second deformed portion 15 is formed in the second hole portion 32 along the inner surface of the third deformed portion 24. The second deformation portion 15 is formed, for example, in a conical shape or a truncated cone shape in which the diameter gradually decreases from the third main surface 21 a toward the fourth main surface 21 b. A substantially entire outer area of the second deformed portion 15 is in contact with the inner surface of the third deformed portion 24, and at least a part of the second deformed portion 15 is joined to the third deformed portion 24. By joining the second deformed portion 15 and the third deformed portion 24, the second conductive layer 13 and the third conductive layer 22 are joined to each other.

The first conductive layer 12 includes a first deformed portion 14 that is bent and deformed in a direction close to the second conductive layer 13. The first deformed portion 14 is formed in the first hole portion 31 along the inner surface of the first hole portion 31. The first deformed portion 14 is formed, for example, in a conical shape or a truncated cone shape in which the diameter gradually decreases from the first main surface 11 a toward the second main surface 11 b. At least a part of the first deformed portion 14 is bonded to the upper surface (opposing surface 13 a) of the second conductive layer 13. By bonding the first deformed portion 14 and the second conductive layer 13, the first conductive layer 12 and the second conductive layer 13 are bonded to each other via the first hole portion 31. The shape of the deformed portions 14, 15, and 24 is not limited to a conical shape or a truncated cone shape. The deformed portions 14, 15, and 24 may be, for example, a quadrangular pyramid shape or a truncated quadrangular pyramid shape whose outer dimensions (size) gradually decrease downward. In this case, the deformed portions 14, 15, 24 are quadrangular (for example, rectangular) in a plan view. In this embodiment, the first deformed portion 14 and the second deformed portion 15 of the first wiring substrate 1 may be referred to as a first substrate deformed portion, and the third deformed portion 24 of the second wiring substrate 2 may be referred to as a first deformed portion. 2In the case of a deformed part of a substrate.

[First Embodiment] (Manufacturing Method of Printed Wiring Board) The manufacturing method of the printed wiring board according to this embodiment includes the first step of preparing a first insulating layer formed on one side of the first insulating layer. The first conductive layer on the first main surface and the first wiring substrate having the second conductive layer formed on the second main surface opposite to the first main surface of the first insulating layer are prepared to have a second insulating layer and be formed thereon. A third conductive layer on a third main surface of one side of the second insulating layer, and a second wiring substrate of a fourth conductive layer on a fourth main surface of the second insulating layer opposite to the third main surface And laminating the first wiring substrate and the second wiring substrate; in a second step, applying ultrasonic waves to the first wiring substrate and the second wiring substrate to perform the first conductive layer and the second conductive layer In the bonding, the bonding of the second conductive layer and the third conductive layer, and the bonding of the third conductive layer and the fourth conductive layer, in the second step, a first hole portion is formed in the first insulating layer. And at least one of the first conductive layer and the second conductive layer faces The first conductive layer and the second conductive layer are joined via the first hole portion, and the second hole portion is formed in the second insulating layer, and the third conductive layer and At least one of the fourth conductive members is bent and deformed in a direction close to the other one, and the third conductive layer and the fourth conductive layer are joined through the second hole portion. Next, the manufacturing method of the printed wiring board concerning 1st Embodiment is demonstrated with reference to FIG. 2A, FIG. 2B, and FIG. 3. FIG. FIG. 2A is a side view showing an outline of the ultrasonic bonding apparatus 200 for manufacturing the printed wiring board 10. FIG. 2B is a plan view showing an outline of the ultrasonic bonding apparatus 200. FIG. 3 is a diagram schematically showing the manufacturing steps of the printed wiring board 10 (see FIG. 1) of FIG. 1.

(First step) As shown in FIG. 2A, the first wiring substrate 1 and the second wiring substrate 2 are laminated. In FIG. 2A, an end region 1A of the first wiring substrate 1 and an end region 2A of the second wiring substrate 2 are overlapped. The first wiring substrate 1 and the second wiring substrate 2 in a laminated state are referred to as a laminated body 3.

(Second step) As shown in FIGS. 2A and 2B, the ultrasonic bonding apparatus 200 includes a welding head 201 and an anvil 202. The horn 201 is provided at a position facing the upper surface 202 a of the anvil 202. The horn 201 has a shape in which the diameter is reduced toward the anvil 202, for example, a conical shape, a quadrangular pyramid shape, or the like. The upper surface 202a of the anvil 202 is a surface on which the laminated body 3 is placed, and is formed in a flat shape.

One of the portions (end regions 1A, 2A) where the first wiring substrate 1 and the second wiring substrate 2 are laminated is disposed between the horn 201 and the anvil 202. The horn 201 is located opposite to the first conductive layer 12 of the first wiring substrate 1, and the anvil 202 is located opposite to the fourth conductive layer 23 of the second wiring substrate 2. The lower surface of the fourth conductive layer 23 is in contact with the upper surface 202 a of the anvil 202.

As shown in FIG. 3, using a horn 201, an ultrasonic wave is applied to the laminated body 3 from the first wiring substrate 1 side. The frequency of the ultrasonic wave is, for example, 10 KHz to 120 KHz. At this time, by applying pressure in the thickness direction to the laminated body 3 according to the horn 201, it is easy to transmit ultrasonic vibration to the laminated body 3.

By applying ultrasonic vibration to the first wiring substrate 1, a first hole portion 31 is formed in the first insulating layer 11, and a part of the first conductive layer 12 is deformed in a direction closer to the second conductive layer 13 to reach the first The first deformed portion 14 of the 2 conductive layer 13. The first deformed portion 14 is bonded to the second conductive layer 13 by ultrasonic vibration. For the bonding of conductive layers by ultrasonic vibration, for example, the oxide film and adhesion on the surface of the conductive layer are removed by vibration, and the new surface is tightly bonded to improve the bonding strength.

Since the first deformed portion 14 is in contact with the second conductive layer 13, the ultrasonic vibration from the welding head 201 is easily transmitted to the second wiring substrate 2. According to the ultrasonic vibration, a second hole portion 32 is formed in the second insulating layer 21, and a second deformed portion 15 and a third deformed portion 24 are formed in the second conductive layer 13 and the third conductive layer 22, respectively. The second deformed portion 15 is joined to the third deformed portion 24 by ultrasonic vibration, and the third deformed portion 24 is joined to the fourth conductive layer 23 by ultrasonic vibration. The fourth conductive layer 23 is hardly deformed and maintains a flat shape. Thereby, the printed wiring board 10 shown in FIG. 1 is obtained.

The first conductive layer 12 and the second conductive layer 13 of the printed wiring board 10 are bonded, and the third conductive layer 22 and the fourth conductive layer 23 are bonded. Therefore, when the first wiring substrate 1 and the second wiring substrate 2 are bonded, External forces do not act on the bonding interface of the conductive layer through the insulating layer. For this reason, the strength of the bonding conductive layer can be increased. Therefore, the first wiring substrate 1 and the second wiring substrate 2 can be firmly bonded.

In the printed wiring board 10, since the second conductive layer 13 includes the second deformed portion 15 along the third deformed portion 24, the second deformed portion 15 is inserted into the third deformed portion 24 and joined thereto. Therefore, the bonding strength between the second conductive layer 13 and the third conductive layer 22 can be increased. Furthermore, since the first conductive layer 12 includes the first deformed portion 14 along the second deformed portion 15, the first deformed portion 14 is inserted into the second deformed portion 15 and joined thereto. Therefore, the bonding strength between the first conductive layer 12 and the second conductive layer 13 can be increased.

[Second Embodiment] (Printed Wiring Board) The configuration of a printed wiring board 110 according to a second embodiment of the present invention will be described with reference to Fig. 4. FIG. 4 is a cross-sectional view schematically showing the printed wiring board 110.

As shown in FIG. 4, the printed wiring board 110 includes a first wiring substrate 101 and a second wiring substrate 102. At least a part of the first wiring substrate 101 and the second wiring substrate 102 are laminated. In the printed wiring board 110, an end region 101A of the first wiring substrate 101 and an end region 102A of the second wiring substrate 102 are overlapped. The end region 101A is a region including the end portion 101 a of the first wiring substrate 101. The end region 102A is a region including the end portion 102 a of the second wiring substrate 102.

The first wiring substrate 101 includes a first insulating layer 111, a first conductive layer 112, and a second conductive layer 113. The first insulating layer 111 is made of an insulating material (described above). The first insulating layer 111 may be a flexible substrate (flexible substrate).

A first hole portion 131 is formed in the first insulating layer 111. The first hole portion 131 is formed through the first insulating layer 111 in the thickness direction. The first hole portion 131 is formed so that the internal shape gradually decreases from the first main surface 111a toward the second main surface 111b. The first hole portion 131 is, for example, circular in a plan view.

The first conductive layer 112 is formed on the first main surface 111 a of the first insulating layer 111. The first main surface 111 a is one surface (the upper surface and the first surface in FIG. 4) of the first insulating layer 111. The second conductive layer 113 is formed on the second main surface 111b of the first insulating layer 111. The second main surface 111b is the other surface (the lower surface and the second surface in FIG. 4) of the first insulating layer 111. The second conductive layer 113 is formed in a flat shape over the entire area along the second main surface 111b. The first conductive layer 112 and the second conductive layer 113 are formed using a conductor such as copper or solder, such as a metal foil such as a copper foil.

The second wiring substrate 102 includes a second insulating layer 121, a third conductive layer 122, and a fourth conductive layer 123. The second insulating layer 121 is made of an insulating material (described above). The second insulating layer 121 may be a flexible substrate (flexible substrate).

A second hole portion 132 is formed in the second insulating layer 121. The second hole portion 132 is formed through the second insulating layer 121 in the thickness direction. The second hole portion 132 is formed such that the internal shape gradually increases from the third main surface 121a toward the fourth main surface 121b. The second hole portion 132 is, for example, circular in a plan view.

The third conductive layer 122 is formed on the third main surface 121 a of the second insulating layer 121. The third main surface 121 a is one surface (the upper surface and the first surface in FIG. 1) of the second insulating layer 121. The third conductive layer 122 is formed in a flat shape over the entire area along the third main surface 121a. The fourth conductive layer 123 is formed on the fourth main surface 121 b of the second insulating layer 121. The fourth main surface 121 b is the other surface (the lower surface and the second surface in FIG. 1) of the second insulating layer 121. The third conductive layer 122 and the fourth conductive layer 123 are formed using a conductor such as copper or solder, such as a metal foil such as a copper foil.

The first conductive layer 112 includes a first deformed portion 114 that is bent and deformed in a direction close to the second conductive layer 113. The first deformed portion 114 is formed in the first hole portion 131 along the inner surface of the first hole portion 131. The first deformed portion 114 is formed, for example, in a conical shape or a truncated cone shape in which the diameter gradually decreases from the first main surface 111 a toward the second main surface 111 b. The first deformed portion 114 is joined to the upper surface (opposing surface 113a) of the second conductive layer 113 at the vertex portion 114a. By bonding the first deformed portion 114 and the second conductive layer 113, the first conductive layer 112 and the second conductive layer 113 are bonded to each other via the first hole portion 131. In addition, at least a part of the first deformed portion 114 may be bonded to the second conductive layer 113.

The fourth conductive layer 123 includes a fourth deformed portion 125 bent and deformed in a direction close to the third conductive layer 122. The fourth deformed portion 125 is formed in the second hole portion 132 along the inner surface of the second hole portion 132. The fourth deformed portion 125 is formed, for example, in a conical shape or a truncated cone shape in which the diameter gradually decreases from the fourth main surface 121b toward the third main surface 121a. The fourth deformed portion 125 is joined to the lower surface (opposing surface 122a) of the third conductive layer 122 at the vertex portion 125a. By bonding the fourth deformed portion 125 and the third conductive layer 122, the third conductive layer 122 and the fourth conductive layer 123 are bonded to each other via the second hole portion 132. In addition, at least a part of the fourth deformed portion 125 may be bonded to the third conductive layer 122. The shape of the deformed portions 114 and 125 is not limited to a conical shape or a truncated cone shape, and a quadrangular pyramid shape or a truncated quadrangular pyramid shape may be used. In this embodiment, the first deformed portion 114 of the first wiring substrate 101 is referred to as a first substrate deformed portion, and the fourth deformed portion 125 of the second wiring substrate 102 is referred to as a second substrate deformed portion.

[Second Embodiment] (Method for Manufacturing Printed Wiring Board) Next, a method for manufacturing a printed wiring board according to the second embodiment will be described with reference to FIG. 5. FIG. 5 is a diagram schematically showing the manufacturing steps of the printed wiring board 110. FIG.

(First Step) As shown in FIG. 5, a first wiring substrate 101 and a second wiring substrate 102 are laminated. The first wiring substrate 101 and the second wiring substrate 102 in a laminated state are referred to as a laminated body.

(Second step) The ultrasonic bonding apparatus 300 includes a welding head 301 and an anvil 302. The welding head 301 is provided at a position opposed to the anvil 302. The welding head 301 has a shape that reduces the diameter (outer dimension) toward the anvil 302, for example, a shape such as a cone shape, a quadrangular pyramid shape, or the like. The anvil 302 has a shape (for example, a cone shape, a quadrangular pyramid shape, etc.) in which a diameter (outer dimension) becomes smaller toward the welding head 301.

Using the horn 301, an ultrasonic wave was applied to the laminated body from the first wiring substrate 101 side. At this time, a pressure in the thickness direction is applied to the laminated body by the welding head 301. By applying ultrasonic vibration to the first wiring substrate 101, a first hole portion 131 is formed in the first insulating layer 111, and a part of the first conductive layer 112 is deformed in a direction closer to the second conductive layer 113 to reach the first The first deformed portion 114 of the two conductive layers 113. The first deformed portion 114 is bonded to the second conductive layer 113 by ultrasonic vibration.

Since the first deformed portion 114 is in contact with the second conductive layer 113, the ultrasonic vibration from the welding head 301 is easily transmitted to the second wiring substrate 102. Ultrasonic vibration is transmitted to the second wiring substrate 102, and pressure in the thickness direction is applied to the second wiring substrate 102 from the lower surface side (the fourth conductive layer 123 side) according to the anvil 302. The second hole portion 132 has a fourth deformed portion 125 formed in the fourth conductive layer 123. The fourth deformed portion 125 is bonded to the third conductive layer 122 by ultrasonic vibration. The second conductive layer 113 and the third conductive layer 122 are hardly deformed and maintain a flat shape. Thereby, the printed wiring board 110 shown in FIG. 4 is obtained.

Since the first conductive layer 112 and the second conductive layer 113 of the printed wiring board 110 are bonded, and the third conductive layer 122 and the fourth conductive layer 123 are bonded, when the first wiring substrate 101 is bonded to the second wiring substrate 102, External forces do not act on the bonding interface of the conductive layer through the insulating layer. For this reason, the strength of the bonding conductive layer can be increased. Therefore, the first wiring substrate 101 and the second wiring substrate 102 can be firmly bonded.

In the printed wiring board 110, since the second conductive layer 113 and the third conductive layer 122 are not deformed, and the deformation of the first conductive layer 112 and the fourth conductive layer 123 can be made small, it is difficult to cause damage to the conductive layer.

The printed wiring board of the said embodiment is not limited to the said illustration, It can change suitably in the range which does not deviate from the meaning of invention. For example, although the printed wiring board 10 shown in FIG. 1 has the first wiring substrate 1 and the second wiring substrate 2 laminated on the end region, the entire area of the first wiring substrate 1 and the second wiring substrate 2 may be laminated. Although the printed wiring board 10 shown in FIG. 1 has only the apex portion 24 a of the third deformed portion 24 joined to the fourth conductive layer 23, at least a part of the third deformed portion 24 may be joined to the fourth conductive layer 23. In the aforementioned second step, when the first conductive layer and the second conductive layer are bonded, at least one of the first conductive layer and the second conductive layer is bent and deformed in a direction closer to the other. At this time, there is no particular limitation on which of the first conductive layer and the second conductive layer is deformed. Further, both the first conductive layer and the second conductive layer may be bent and deformed in a direction approaching each other. Since the printed wiring board 10 shown in FIG. 1 has a structure in which a plurality of wiring substrates are laminated, it is a composite wiring substrate. Although the printed wiring board 10 includes two wiring substrates, the printed wiring board according to the present embodiment may have a structure in which any number of wiring substrates of three or more layers are laminated. As shown in the first embodiment, the first deformed portion 14 and the second deformed portion 15 of the first wiring substrate 1 are referred to as a first substrate deformed portion, and the third deformed portion 24 of the second wiring substrate 2 This is called a second substrate deformed portion. As shown in the second embodiment, the first deformed portion 114 of the first wiring substrate 101 is referred to as a first substrate deformed portion, and the fourth deformed portion 125 of the second wiring substrate 102 is referred to as a second substrate deformed portion. . In other words, the deformed portion of the first wiring substrate may be referred to as a first substrate deformed portion, and the deformed portion of the second wiring substrate may be referred to as a second substrate deformed portion. That is, in the aforementioned embodiment, the first wiring substrate has a first substrate deforming portion that bends and deforms at least one of the first conductive layer and the second conductive layer. Moreover, in the said embodiment, the 2nd wiring board has a 2nd board | substrate deformation | transformation part which bend-deforms at least any one of a 3rd conductive layer and a 4th conductive layer.

1,101‧‧‧1st wiring board

2,102‧‧‧Second wiring board

10,110‧‧‧Printed wiring board

11,111‧‧‧1st insulation layer

11a, 111a‧‧‧ 1st main face

11b, 111b‧‧‧ 2nd main face

12,112‧‧‧The first conductive layer

13,113‧‧‧Second conductive layer

13a‧‧‧ opposite

21,121‧‧‧Second insulation layer

21a, 121a ‧ ‧ 3rd main face

21b, 121b ‧‧‧ 4th main face

22,122‧‧‧The third conductive layer

23,123‧‧‧4th conductive layer

23a‧‧‧ opposite

31,131‧‧‧The first hole

32,132‧‧‧ 2nd hole

14,114‧‧‧The first deformed part (one of the first substrate deformed parts)

15‧‧‧ the second deformed part (one of the first substrate deformed parts)

24‧‧‧ The third deformed part (one of the second substrate deformed parts)

125‧‧‧ 4th deformed part (one of the second substrate deformed parts)

200,300‧‧‧ultrasonic bonding device

201,301‧‧‧welding head

202,302‧‧‧Anvil

202a‧‧‧ above

FIG. 1 is a cross-sectional view schematically showing a printed wiring board according to the first embodiment. FIG. 2A is a side view showing an outline of an ultrasonic bonding apparatus for manufacturing the printed wiring board of FIG. 1. FIG. FIG. 2B is a plan view showing the outline of the ultrasonic bonding apparatus shown in FIG. 2A. FIG. 3 is a diagram schematically showing the manufacturing steps of the printed wiring board of FIG. 1. FIG. Fig. 4 is a sectional view schematically showing a printed wiring board according to a second embodiment. FIG. 5 is a diagram schematically showing the manufacturing steps of the printed wiring board of FIG. 4.

Claims (6)

A printed wiring board includes a first wiring substrate and a second wiring substrate. The first wiring substrate includes: a first insulating layer having a first main surface; and a second main surface and a first main surface opposite to the first main surface. A hole portion; a first conductive layer formed on the first main surface; a second conductive layer formed on the second main surface and bonded to the first conductive layer through the first hole portion; and a first substrate deformed portion At least one of the first conductive layer and the second conductive layer is bent and deformed, the second wiring substrate is laminated on the first wiring substrate, and has: a second insulating layer having a third main surface; 4 main surface opposite to the 3 main surface and second hole portion; a third conductive layer formed on the third main surface and bonded to the second conductive layer; a fourth conductive layer formed on the fourth main surface through The second hole portion is connected to the third conductive layer; and the second substrate deforming portion bends and deforms at least one of the third conductive layer and the fourth conductive layer. The printed wiring board according to claim 1, wherein the fourth conductive layer is formed in a flat shape, and the third conductive layer is bent and deformed in the second hole portion in a direction close to the fourth conductive layer, and at least a part of the third conductive layer is in contact with the fourth conductive layer. Layer-bonded, and has one of the second substrate deformed portions, that is, a third deformed portion, the second conductive layer is bent and deformed along the third deformed portion and at least part of the second conductive layer is joined to the third conductive layer, and has the first One of the substrate deformed portions is a second deformed portion. The first conductive layer is bent and deformed along the second deformed portion and at least a part of the first conductive layer is joined to the second conductive layer, and one of the first substrate deformed portions is also a first deformed portion. 1 deformed part. The printed wiring board according to claim 1, wherein the second conductive layer is formed in a flat shape, and the first conductive layer is bent and deformed in the first hole portion in a direction close to the second conductive layer, and at least a part of the second conductive layer is in contact with the second conductive layer. Layer bonding, and has one of the first substrate deformed portions, that is, the first deformed portion, the third conductive layer is formed in a flat shape, and the fourth conductive layer faces the third conductive layer in the second hole portion. It is bent and deformed, and at least a part of the second conductive layer is bonded to the third conductive layer. The fourth conductive portion also has a fourth deformed portion, which is one of the second substrate deformed portions. A method for manufacturing a printed wiring board, comprising a first step and a second step, wherein the first step: preparing a first wiring substrate, preparing a second wiring substrate, and laminating the first wiring substrate and the second wiring substrate; The first wiring substrate includes: a first insulating layer; a first conductive layer formed on one side of the first insulating layer, that is, a first main surface; and a second conductive layer formed on the first insulating layer and the first first layer. On the second main surface opposite to the main surface, the second wiring substrate includes: a second insulating layer; a third conductive layer formed on one side of the second insulating layer, that is, a third main surface; and a fourth conductive layer formed on A fourth main surface of the second insulating layer opposite to the third main surface; the second step: applying an ultrasonic wave to the first wiring substrate and the second wiring substrate to perform the first conductive layer and the second conductive layer; In the second step, the bonding of the second conductive layer, the bonding of the second conductive layer and the third conductive layer, and the bonding of the third conductive layer and the fourth conductive layer are in the first insulating layer in the second step. A first hole is formed, and the first conductive layer and At least one of the second conductive layers is bent and deformed in a direction closer to the other to join the first conductive layer and the second conductive layer through the first hole portion, and a second hole portion is formed in the second insulating layer. And at least one of the third conductive layer and the fourth conductive layer is bent and deformed in a direction close to the other, and the third conductive layer and the fourth conductive layer are joined via the second hole portion. The method of manufacturing a printed wiring board according to claim 4, wherein in the second step, a third deformed portion is formed on the third conductive layer by applying the ultrasonic waves and pressure from the first conductive layer, and the third The deformed portion is bent and deformed in a direction close to the fourth conductive layer in the second hole portion, and at least a portion is joined to the fourth conductive layer. A second deformed portion is formed in the second conductive layer, and the second deformed portion is along the aforementioned The third deformed portion is bent and deformed to join at least a portion with the third conductive layer. A first deformed portion is formed in the first conductive layer. The first deformed portion is bent and deformed along the second deformed portion, and at least a portion of the first deformed portion is bent to the second The conductive layers are bonded. The method for manufacturing a printed wiring board according to claim 4, wherein in the aforementioned second step, the ultrasonic waves and pressure are applied from the first conductive layer, and the pressure is applied from the fourth conductive layer, and the first conductive layer is applied to the first conductive layer. The layer forms a first deformed portion, and the first deformed portion is bent and deformed in the first hole portion in a direction close to the second conductive layer, and at least a part of the first deformed portion is joined to the second conductive layer, and pressure is applied from the fourth conductive layer. A fourth deformed portion is formed in the fourth conductive layer, and the fourth deformed portion is bent and deformed in a direction close to the third conductive layer in the second hole portion, and at least a part of the fourth deformed portion is bonded to the third conductive layer.