JP2009289789A - Printed wiring board with built-in component and its manufacturing method - Google Patents

Abstract

Provided is a printed wiring board with built-in components in which built-in electronic circuit components have high reliability.
A base substrate 1 having a component mounting surface 1a, one or more electronic circuit components 2 (2a to 2d) mounted on the component mounting surface 1a, and a component mounting surface 1a of the base substrate 1 are provided. And a sheet-like stress relaxation layer 3 that collectively covers the component mounting surface 1a and the electronic circuit components 2 (2a to 2d), and an insulating layer 4 provided on the stress relaxation layer 3. A printed wiring board 20 with a built-in component.
[Selection] Figure 1

Description

  The present invention relates to an improvement in a component built-in printed wiring board and a method for manufacturing a component built-in printed wiring board.

  In small electronic devices such as portable terminals, functions and miniaturization have progressed, functions to be integrated into semiconductor integrated circuit elements have expanded, and the number of input / output terminals for the semiconductor integrated circuit elements has increased. For this reason, the number of packages mounted on printed wiring boards has been increasing. On the other hand, in order to reduce the size of an electronic device, a small semiconductor package having a large number of pins is required. Conventionally, a semiconductor package such as a ball grid array (BGA) has been widely used. This BGA semiconductor package is configured by mounting a semiconductor integrated circuit element on a substrate such as a printed wiring board and sealing the mounted semiconductor integrated circuit element with a resin.

  By the way, in recent years, as a printed wiring board for forming a plurality of layers, a chip component such as a capacitor is soldered on a pad made of a conductive pattern formed on a pattern forming surface on the inner layer side, and an insulating material is laminated on the inner layer side. By covering the chip parts with an insulating material, the manufacturing technology of the printed wiring boards with built-in parts has been developed for practical use.

  However, in the printed wiring board with a built-in component as described above, the chip component is removed from the insulating material in the process of laminating the printed wiring board on the inner layer side on which the chip component is mounted and the insulating material by hot pressing in a vacuum state. There was a problem that it was destroyed by the transmitted stress. For this reason, a means for protecting the built-in chip component mounted on the inner layer side from external stress or stress due to thermal expansion is required.

Therefore, in Patent Document 1, in the above-described component built-in printed wiring board, a space for accommodating a built-in chip component mounted on the inner layer side is provided in a layer made of an insulating material. A configuration of a printed wiring board with a built-in component is disclosed in which the chip component is covered with a stress relaxation material to protect it from the stress, and a space between the chip component and the space provided in the insulating material is filled with the stress relaxation material. ing. That is, Patent Document 1 discloses a component built-in printed wiring board in which mounted chip components are individually covered with a stress relaxation material and laminated with an insulating material, and a manufacturing method.
JP 2007-273583 A

  However, in the component built-in printed wiring board disclosed in Patent Document 1, since only the chip component is covered with the stress relaxation material, a step is generated on the mounting surface and the mounting surface of the substrate on which the component is mounted and the insulating material are included. Since the height difference from the layer becomes large, there is a problem that the layer made of an insulating material cannot be embedded sufficiently. For this reason, there is a problem that the reliability of the built-in electronic circuit component is not sufficient. In addition, since the alignment between the chip component and the space provided in the layer made of the insulating material is shifted, when the built-in chip component mounted on the inner layer side is covered with the stress relaxation material, the chip component and the stress relaxation material There is a problem that alignment is difficult because high alignment accuracy is required. Further, when a plurality of chip parts are mounted, there is a problem that the number of processes increases because the stress relaxation material is individually coated on the chip parts, and the productivity deteriorates.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a component built-in printed wiring board with high reliability of a built-in electronic circuit component.
It is another object of the present invention to provide a method for manufacturing the component built-in printed wiring board with high productivity.

In order to achieve the above object, the present invention employs the following configuration.
That is, the component built-in printed wiring board according to the present invention is provided on a base substrate having a component mounting surface, one or more electronic circuit components mounted on the component mounting surface, and the component mounting surface of the base substrate. And a sheet-like stress relaxation layer that collectively covers the component mounting surface and the electronic circuit component, and an insulating layer provided on the stress relaxation layer.

  Moreover, the component built-in printed wiring board of the present invention includes at least a through hole penetrating the stress relaxation layer, and the stress relaxation layer has an opening larger than the through hole in a portion through which the through hole penetrates. The stress relaxation layer and the through hole are preferably not in contact with each other. Furthermore, it is preferable to provide a single layer or a plurality of wiring layers on the insulating layer.

  The method for manufacturing a component built-in printed wiring board according to the present invention includes a step of mounting one or more electronic circuit components on a component mounting surface of a base substrate, and a step of forming a sheet-like stress relaxation layer on the component mounting surface. And a step of forming an insulating layer on the stress relaxation layer.

  In the method of manufacturing a component built-in printed wiring board according to the present invention, an opening for penetrating a through hole is formed in the sheet-like stress relaxation layer, and the component mounting surface and the sheet-like stress relaxation layer are formed. It is preferable to provide a step of penetrating through holes in the openings after alignment and lamination. Furthermore, it is preferable to include a step of laminating a single layer or a plurality of wiring layers on the insulating layer.

According to the component built-in printed wiring board of the present invention, the sheet-like stress relaxation layer provided on the component mounting surface of the base substrate collectively covers the component mounting surface and one or more electronic circuit components. Yes. Thus, since the sheet-like stress relaxation layer is provided between the base substrate and the insulating layer, a large step does not occur on the component mounting surface. Thereby, it can adhere reliably, without a gap | interval producing between a stress relaxation layer and an insulating layer.
In addition, even when there is a deviation in the alignment between the electronic circuit component and the insulating layer, the sheet-like stress relaxation layer collectively covers the electronic circuit component. In this case, high alignment accuracy is not required. Accordingly, the electronic circuit component is reliably protected by the stress relaxation layer, and the layers of the base substrate, the stress relaxation layer, and the insulating layer are reliably stacked. Therefore, it is possible to provide a component built-in printed wiring board with high reliability of the built-in electronic circuit component.

  According to the component built-in printed wiring board of the present invention, when the component built-in printed wiring board is provided with a through-hole penetrating the sheet-like stress relaxation layer, the sheet-like stress relaxation layer has a through-hole. The through portion has an opening larger than the through hole, and the stress relaxation layer and the through hole are not in contact with each other. For this reason, the plating solution does not come into contact with the stress relaxation layer when the internal conductor is formed by plating inside the through hole. Thereby, even if it is a material which is excellent in stress relaxation performance and does not have plating solution tolerance, it can be used as a stress relaxation layer.

  Furthermore, according to the component built-in printed wiring board of the present invention, since the wiring layer of a single layer or a plurality of layers is provided on the insulating layer, the component built-in printed wiring board constituting the multilayer printed wiring board together with the base substrate is provided. Can be provided.

  According to the manufacturing method of the component built-in printed wiring board of the present invention, the method includes a step of forming a sheet-like stress relaxation layer on the component mounting surface. Thereby, one or more electronic circuit components mounted on the component mounting surface can be collectively covered without individually covering them. For this reason, even if it is a case where the number of the mounted electronic circuit components increases, the number of processes does not increase. Therefore, it is possible to provide a method for manufacturing a component built-in printed wiring board with high productivity.

  Further, according to the method for manufacturing a component built-in printed wiring board of the present invention, an opening for penetrating a through hole is formed in a sheet-like stress relaxation layer, and the component mounting surface and the sheet-like stress relaxation layer are formed. After the alignment and lamination, the structure includes a step of penetrating the through hole through the opening. Thereby, even when a through hole is formed in the component built-in printed wiring board, the contact between the plating solution and the stress relaxation layer can be easily avoided without requiring a high degree of alignment. Therefore, even a material having excellent stress relaxation performance and not having plating solution resistance can be used as a sheet-like stress relaxation layer.

  Furthermore, according to the manufacturing method of the component built-in printed wiring board of the present invention, since it includes a step of laminating a single layer or a plurality of wiring layers on the insulating layer, the multilayer printed wiring board is configured together with the base substrate. A method of manufacturing a component built-in printed wiring board can be provided.

As described above, according to the component built-in printed wiring board of the present invention, the built-in components can be reliably protected.
Moreover, according to the component built-in printed wiring board of the present invention, the productivity of the component built-in printed wiring board can be improved.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic sectional view showing a component built-in printed wiring board according to an embodiment of the present invention. 2-8 is process sectional drawing which shows the manufacturing method of the component built-in printed wiring board which is one Embodiment of this invention. 1-8 is for demonstrating the structure of the component built-in printed wiring board wiring and its manufacturing method which is one Embodiment of this invention, The magnitude | size of each part shown, thickness, a dimension, etc. The actual dimensional relationship of the component built-in printed wiring board may be different.

First, a component built-in printed wiring board according to an embodiment of the present invention will be described.
As shown in FIG. 1, a component built-in printed wiring board 20 according to the present embodiment includes a base substrate 1 having a component mounting surface 1a and electronic circuit components 2 (2a, 2b, 2c, 2) mounted on the component mounting surface 1a. 2d), a sheet-like stress relaxation layer 3 provided on the component mounting surface 1a and collectively covering the component mounting surface 1a and the electronic circuit component 2, and an insulating layer 4 provided on the stress relaxation layer 3 And. More specifically, a single wiring layer 5 is provided on the insulating layer 4, and a through hole 6 and a via hole 7 that penetrate the component built-in printed wiring board 20 are formed. Yes.

  As shown in FIG. 1, the base substrate 1 is a double-sided printed wiring board formed by laminating a sheet-like member made of an insulating material and wiring layers 8 and 9. Further, an electronic circuit component 2 is mounted on the inner layer side surface of the base substrate 1 to form a component mounting surface 1a. On the other hand, the surface on the outer layer side of the base substrate 1 is a pattern forming surface 1b.

  The material having insulating properties is not particularly limited, and can be appropriately selected according to the function given to the base substrate 1. For example, when the base substrate 1 is given flexibility, an insulating resin such as polyimide can be applied. When flexibility is not given, a prepreg in which a glass cloth is impregnated with resin Can be applied. Furthermore, a plurality of insulating materials may be used in combination.

  A wiring layer 8 is provided on the component mounting surface 1a of the base substrate 1, and a plurality of conductor patterns 8a to 8f including electrode pads for mounting the mounting surface of the electronic circuit component 2 to be mounted are formed. ing.

On the other hand, a wiring layer 9 is provided on the pattern forming surface 1b on the outer layer side of the base substrate 1, and a plurality of conductor patterns 9a, 9d, 9e, 9f as shown in FIG. 1 are formed.
Further, the base substrate 1 has a via hole 10 formed through the conductor patterns 8e and 9e. The via hole 10 is provided with the inside filled with a conductive material such as silver paste, whereby the wiring layers 8 and 9 are connected to each other in the base substrate 1.

  The electronic circuit component 2 is an active element having two or more terminals having a specific operation function. As shown in FIG. 1, the electronic circuit component 2 is chip components 2a, 2b, 2c, and 2d in which a rectangular parallelepiped component body is provided with a pair of terminals, and examples of chip components such as capacitors and resistance elements are shown. Can do.

  As shown in FIG. 1, the terminals of the electronic circuit components 2 (2a to 2d) are soldered to the conductor patterns 8 (8a to 8d) constituting the electrode pads formed on the component mounting surface 1a. Is mounted on the component mounting surface 1a. Note that a sealing resin (underfill) may be filled between the electronic circuit component 2 and the conductor pattern 8.

  As shown in FIG. 1, the stress relaxation layer 3 is a continuous sheet-like layer for relaxing the stress on the electronic circuit component 2 and suppressing the destruction of the electronic circuit component 2, and on the component mounting surface 1a. Laminated and provided. Thereby, the stress relaxation layer 3 can coat | cover the component mounting surface 1a and the one or more electronic circuit components 2a-2d collectively.

  Thus, the component mounting surface 1a and the one or more electronic circuit components 2a to 2d are collectively covered with the sheet-like stress relaxation layer 3, so that the component mounting surface 1a of the base substrate 1 and the insulating layer 4 are covered. It is possible to improve the adhesion between the respective layers without causing a step between them. Furthermore, damage due to stress on the component mounting surface 1a in the stacking process can be suppressed, and thermal stress due to a difference in thermal expansion coefficient between the base substrate 1 and the insulating layer 4 can be reduced.

  The material of the stress relaxation layer 3 is not particularly limited as long as it can be protected from external stress on the electronic circuit component 2. For the stress relaxation layer 3, for example, a resin material such as rubber, elastomer, or polyurethane, and a fiber material woven while incorporating an air layer therein can be used. In addition, when the adhesiveness with the component mounting surface 1a and the insulating layer 4 is hard to be acquired, you may provide the contact bonding layer which consists of an adhesive agent on the surface of the stress relaxation layer 3. FIG. The stress relaxation layer 3 of the present invention may be formed on the component mounting surface 1a, but is preferably a sheet member made of a material that relieves stress.

  The insulating layer 4 is provided by being laminated on the stress relaxation layer 3. The material of the insulating layer 4 is not particularly limited, and can be appropriately selected according to the function given to the component built-in printed wiring board 20. For example, in the case where flexibility is given to the component built-in printed wiring board 20, an insulating resin such as polyimide can be applied, and in the case where flexibility is not given, a glass cloth is impregnated with resin. Prepreg can be applied. The thickness of the insulating layer 4 is not particularly limited, but is configured to be at least larger than the height after mounting the electronic circuit components 2a to 2d. Thus, in order to adjust the insulating layer 4 to a predetermined layer thickness, a single member having a predetermined thickness may be used, or a plurality of insulating members having different thicknesses may be used in combination. Also good.

  The component mounting surface 1a, the electronic circuit component 2, and the stress relaxation layer 3 are stacked so that no gap is generated at the interface. Further, the stress relaxation layer 3 and the insulating layer 4 are laminated so that no gap is generated at the interface.

  The wiring layer 5 is a wiring layer made of a conductive material such as copper, and is provided by being laminated on the insulating layer 4. In the wiring layer 5, a plurality of conductor patterns 5a to 5e are formed. Although the wiring layer 5 is composed of a single wiring layer in this embodiment, the wiring layer 5 is not limited to this and may be a plurality of wiring layers. For example, a double-sided printed wiring board or a multilayer printed wiring board may be used as the wiring layer 5.

  As shown in FIG. 1, the component built-in printed wiring board 20 has through holes 6 formed so as to penetrate through the conductor patterns 8 f and 9 f of the base substrate 1 and the conductor pattern 5 c of the wiring layer 5. Inside the through hole 6, an internal conductor 6a formed by a plating method is provided. Further, the component built-in printed wiring board 20 is provided with a via hole 7 for conducting the wiring layer 9 on the outer layer side and the wiring layer 8 on the inner layer side. In this way, the component built-in printed wiring board 20 is configured so that conduction can be freely established between the wiring layers of the wiring layers 5 and 8 on the outer layer side and the wiring layer 9 on the inner layer side.

Thus, the component built-in printed wiring board 20 of the present embodiment includes the through hole 6 that penetrates the stress relaxation layer 3. Further, as described above, a plating method is generally used to form the inner conductor 6a of the through hole 6.
By the way, when the stress relaxation layer 3 is a material inferior in chemical resistance or a material into which the plating solution penetrates, the stress relaxation layer 3 cannot perform its original function, or the electronic component circuit Such a problem occurs that 2 corrodes.

  Therefore, as described above, when the stress relaxation layer 3 is a material having poor chemical resistance or a material into which the plating solution penetrates, the stress relaxation layer 3 has a portion through which the through hole 6 penetrates. It is preferable that an opening 3 a larger than the through hole 6 is formed so that the stress relaxation layer 3 and the inner conductor 6 a of the through hole 6 do not contact each other. Thereby, in the plating process for forming the inner conductor 6a of the through hole 6, since it does not come into contact with the plating solution, problems such as deterioration and corrosion do not occur. Even a material that permeates can be applied to the stress relaxation layer 3.

  Further, as shown in FIG. 1, the opening 3a of the stress relaxation layer 3 is provided so as to be on the conductor pattern 8f constituting the through-hole land, but is not particularly limited thereto. For example, the opening 3a may be formed larger than the conductor pattern 8f so that the stress relaxation layer 3 does not contact the conductor pattern 8f at all. That is, it is possible to design relatively freely within the range of the design rule such as the distance between the electronic circuit component 2 and the through hole 6.

  Furthermore, the opening 3a of the stress relaxation layer 3 is not limited to the location where the through hole 6 as described above is provided, and is between the component mounting surface 1a and the insulating layer 4 and is provided between the stress relaxation layer 3 and the stress relaxation layer 3. It is also possible to arbitrarily provide a portion in which it is not desired to provide.

Next, an example of a manufacturing method of the component built-in printed wiring board 20 shown in FIG. 1 will be described.
The manufacturing method of the component built-in printed wiring board 20 of the present embodiment includes a step of mounting one or more electronic circuit components 2 on the component mounting surface 1a of the base substrate 1, and a sheet-like stress relaxation on the component mounting surface 1a. The process generally includes a step of forming the layer 3, a step of forming the insulating layer 4 on the stress relaxation layer 3, and a step of laminating the wiring layer 5 on the insulating layer 4. Hereinafter, each step will be described in detail.

<Electronic circuit component mounting process>
First, a process of mounting the electronic circuit component 2 on the component mounting surface 1a surface of the base substrate 1 (hereinafter referred to as an electronic circuit component mounting process) will be described.
As shown in FIG. 2, the electronic circuit component mounting step is performed by first masking the pattern forming surface 1b on the outer layer side of the base substrate 1 and patterning the wiring layer 8 on the component mounting surface 1a to form a conductor pattern 8a. ~ 8f are formed.

Next, as shown in FIG. 3, the terminals of the electronic circuit components 2a to 2d are joined to the conductor patterns 8a, 8b, 8c, and 8d constituting the electrode pads provided on the base substrate 1 by soldering, respectively. One or more electronic circuit components 2 (2a to 2d) are mounted on the component mounting surface 1a. Note that sealing resin (underfill) may be injected between the component mounting surface 1a and the electronic circuit component 2 as necessary.
Next, a via hole 10 for establishing electrical connection between the wiring layer 8 on the component mounting surface 1a and the wiring layer 9 on the pattern forming surface 1b is formed by a laser or a drill, and the inside is filled with a conductive substance. Alternatively, a through hole may be provided when the base substrate 1 is first manufactured. In that case, it becomes BVH (Blind Via Hole) or IVH (Interstitial Via Hole) by the heat press process mentioned later.

<Lamination process>
Next, a step of forming the sheet-like stress relaxation layer 3 on the component mounting surface 1a, a step of forming the insulating layer 4 on the stress relaxation layer 3, and a step of laminating the wiring layer 5 on the insulating layer 4 (hereinafter, Will be described.
In the laminating step, first, as shown in FIG. 4, a sheet-like stress relaxation layer 3, an insulating layer 4, and a wiring layer 5 are prepared. In the stress relaxation layer 3, for example, an opening 3 a for penetrating the through hole is formed by using a conventional method such as laser, drill, punch, or die cutting. On the other hand, the insulating layer 4 prepares sheet-like insulating layer constituent members 4A to 4E made of prepreg or polyimide resin. These thickness and material are different insulating layers constituting member 4A - 4D, the position corresponding to the electronic circuit component 2 a to 2 d, the opening _{4a 1 ~4a 4, 4b 1 ~4b} 3, 4c 1 ~4c 3, 4d _{1 to} 4d ₃ are formed. Moreover, the prepreg in which the opening part is not provided is prepared for the insulating layer structural member 4E. Furthermore, for the wiring layer 5, a conductive sheet such as a copper foil, which becomes a single wiring layer, is prepared.

Next, as shown in FIG. 5, the sheet-like stress relaxation layer 3 is laminated on the component mounting surface 1a. At this time, the stress relaxation layer 3 is aligned on the component mounting surface 1a so that the opening 3a is on the conductor pattern 8f constituting the through-hole land. If the opening 3a is sufficiently larger than the through hole 6, the alignment can be easily performed.
Here, by using the sheet-like stress relaxation layer 3, it is possible to collectively cover the plurality of electronic circuit components 2 (2a to 2d) without individually aligning them. Thereby, even when the number of electronic circuit components 2 increases, productivity does not fall.

  Next, as shown in FIG. 5, the insulating layer 4 is formed on the stress relaxation layer 3 by laminating the insulating layer constituting members 4A, 4B, 4C, 4D, and 4E in this order. At this time, the electronic circuit components 2a, 2b, 2c and 2d covered with the stress relaxation layer 3 are aligned so that they are accommodated in the openings 4a, 4b, 4c and 4d formed in the insulating layer 4.

Next, as shown in FIG. 5, a wiring layer 5 made of a conductive sheet is laminated on the insulating layer 4.
In addition, although the stress relaxation layer 3, the insulating layer 4, and the wiring layer 5 may be laminated | stacked in order, when all are sheet-like members, it is preferable to laminate | stack collectively. Thereby, productivity can be improved significantly.

  Finally, a heat press process is performed in a vacuum state using a vacuum press apparatus or the like. In the present invention, since the sheet-like stress relaxation layer 3 is provided between the component mounting surface 1a and the electronic circuit component 2 and the insulating layer 4, the electronic circuit component 2 when performing the heat press in a vacuum state. The stress of can be relieved. Thereby, the electronic circuit component 2 is not destroyed. Further, since the sheet-like stress relaxation layer 3 is used, a large step does not occur at the component mounting surface 1a, the interface between the electronic circuit component 2 and the stress relaxation layer 3, and the interface between the stress relaxation layer 3 and the insulating layer 4. Further, it is possible to reliably stack without causing a gap between the layers.

<Pattern formation process>
Finally, a process for forming the through hole 6 and the via hole 7 and a process for forming the patterns 5 and 9 on the outer layer side (hereinafter referred to as a pattern forming process) will be described.
In the pattern forming step, as shown in FIG. 6, first, a hole for forming the through hole 6 and the via hole 7 and the like by laser processing or drilling is formed on the component built-in printed wiring board in which the respective base materials are integrated. Process.

Next, as shown in FIG. 7, the inner conductors 6a and 7a are formed by plating the inner walls of the holes for forming the through holes 6 and the via holes 7 and the wiring layers 5 and 9 on the outer layer side. To do. In this manner, the through hole 6 and the via hole 7 that electrically connect the conductor patterns between the respective layers are formed.
In addition, since the opening part 3a is provided in the sheet-like stress relaxation layer 3, a stress relaxation layer and a plating solution do not contact.

Finally, as shown in FIG. 8, conductor patterns 5a to 5e and conductor patterns 9a, 9d, 9e, and 9f are formed on the wiring layers 5 and 9 on the outer layer side using a known method.
Thus, the component built-in printed wiring board 20 of this embodiment as shown in FIG. 1 can be manufactured.

  As described above, according to the component built-in printed wiring board 20 of the present embodiment, the sheet-like stress relaxation layer 3 provided on the component mounting surface 1a of the base substrate 1 has one or more component mounting surfaces 1a. The electronic circuit component 2 (2a to 2d) is collectively covered. Thus, since the sheet-like stress relaxation layer 3 is provided between the base substrate 1 and the insulating layer 4, a large step does not occur on the component mounting surface 1a. As a result, the stress relaxation layer 3 and the insulating layer 4 can be reliably adhered without a gap.

  Further, even when there is a deviation in alignment between the electronic circuit component 2 and the insulating layer 4, the sheet-like stress relaxation layer 3 collectively covers the electronic circuit components 2 (2a to 2d). Therefore, high alignment accuracy is not required between the electronic circuit component 2 and the stress relaxation layer 3. Thereby, the electronic circuit component 2 is reliably protected by the stress relaxation layer 3 and the layers of the base substrate 1, the stress relaxation layer 3, and the insulating layer 4 are reliably laminated. Therefore, the built-in component printed wiring board 20 with high reliability of the built-in electronic circuit component 2 can be provided.

  In addition, according to the component built-in printed wiring board 20 of the present embodiment, when the through hole 6 penetrating the sheet-like stress relaxation layer 3 is provided in the component built-in printed wiring board 20, the sheet-like stress relaxation. The layer 3 has an opening 3a larger than the through hole 6 at a portion through which the through hole 6 passes, and the stress relaxation layer 3 and the through hole 6 are not in contact with each other. For this reason, the plating solution does not come into contact with the stress relaxation layer 3 when forming the inner conductor 6 a by plating inside the through hole 6. Thereby, even a material having excellent stress relaxation performance and not having resistance to plating solution can be used as the stress relaxation layer 3.

  Furthermore, according to the component built-in printed wiring board 20 of the present embodiment, since the single-layer wiring layer 5 is provided on the insulating layer 3, the component built-in printed wiring constituting the multilayer printed wiring board together with the base substrate 1. A plate 20 can be provided.

  According to the manufacturing method of the component built-in printed wiring board 20 of the present embodiment, it is configured to include a step of forming the sheet-like stress relaxation layer 3 on the component mounting surface 1a. Thereby, one or more electronic circuit components 2 (2a to 2d) mounted on the component mounting surface 1a can be collectively covered without individually covering them. For this reason, even if it is a case where the number of the mounted electronic circuit components 2 increases, the number of processes does not increase. Therefore, the manufacturing method of the component built-in printed wiring board 20 with high productivity can be provided.

  Moreover, according to the manufacturing method of the component built-in printed wiring board 20 of this embodiment, the opening 3a for penetrating the through hole 6 is formed in the sheet-like stress relaxation layer 3, and the component mounting surface 1a and the sheet-like surface are formed. After the stress relaxation layer 3 is aligned and laminated, the step of passing the through hole 6 through the opening 3a is provided. Thereby, the contact between the plating solution and the stress relaxation layer 3 can be easily avoided without requiring a high degree of alignment. Therefore, even a material having excellent stress relaxation performance and not having resistance to plating solution can be used as the sheet-like stress relaxation layer 3.

  Furthermore, according to the manufacturing method of the component built-in printed wiring board 20 of the present embodiment, since the process includes the step of laminating the single-layer wiring layer 5 on the insulating layer 4, The manufacturing method of the component built-in printed wiring board 20 to comprise can be provided.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the method of manufacturing the component built-in printed wiring board 20 according to the above-described embodiment, the step of forming the sheet-like stress relaxation layer 3 on the component mounting surface 1a includes a sheet-like member made of a material that relieves stress. The step of laminating on the mounting surface 1a may be a step of forming a sheet-like stress relaxation layer 3 by applying a member made of a material that relieves stress on the component mounting surface 1a and the electronic circuit component 2. . In the case of such a process, since the filling property between the component mounting surface 1a and the electronic circuit component 2 is improved, it is possible to relax the conditions for heating and pressing in a vacuum state. Such a process can also suppress destruction of built-in components.

FIG. 1 is a schematic sectional view showing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 2 is a process cross-sectional view illustrating a method of manufacturing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 3 is a process cross-sectional view illustrating a method of manufacturing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 4 is a process cross-sectional view illustrating a method of manufacturing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 5 is a process cross-sectional view illustrating a method of manufacturing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 6 is a process cross-sectional view illustrating a method of manufacturing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 7 is a process cross-sectional view illustrating a method of manufacturing a component built-in printed wiring board according to an embodiment of the present invention. FIG. 8 is a process cross-sectional view illustrating a method for manufacturing a component built-in printed wiring board according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Base substrate, 1a ... Component mounting surface, 2 (2a-2d) ... Electronic circuit component, 3 ... Stress relaxation layer, 3a ... Opening, 4 ... Insulating layer, 5 ... Wiring layer, 6 ... Through hole, 7 , 10: Via hole, 8, 9 ... Wiring layer, 20 ... Printed wiring board with built-in components

Claims (6)

A base substrate having a component mounting surface;
One or more electronic circuit components mounted on the component mounting surface;
A sheet-like stress relaxation layer that is provided on the component mounting surface of the base substrate and collectively covers the component mounting surface and the electronic circuit component;
A printed wiring board with a built-in component, comprising: an insulating layer provided on the stress relaxation layer. Comprising a through hole penetrating at least the stress relaxation layer,
The stress relaxation layer has an opening larger than the through hole in a portion through which the through hole penetrates,
The component built-in printed wiring board according to claim 1, wherein the stress relaxation layer does not contact the through hole.   The component built-in printed wiring board according to claim 1, further comprising a single layer or a plurality of wiring layers on the insulating layer. Mounting one or more electronic circuit components on the component mounting surface of the base substrate;
Forming a sheet-like stress relaxation layer on the component mounting surface;
And a step of forming an insulating layer on the stress relieving layer.   An opening for penetrating a through hole is formed in the sheet-like stress relaxation layer, and the component mounting surface and the sheet-like stress relaxation layer are aligned and laminated, and then a through-hole is formed in the opening. The manufacturing method of the component built-in printed wiring board according to claim 4, further comprising a step of penetrating.   6. The method of manufacturing a component built-in printed wiring board according to claim 4, further comprising a step of laminating a single layer or a plurality of wiring layers on the insulating layer.

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