JP2021158309A - Wiring board, wiring board module, and base material - Google Patents

Abstract

To suppress mutual thermal interference between an inner layer component and a built-in component.SOLUTION: A wiring board has a first main surface orthogonal to the thickness direction and a second main surface facing the first main surface. The wiring board includes a first wiring layer provided on the first main surface side, a second wiring layer provided on the second main surface side, a base material that is sandwiched between the first wiring layer and the second wiring layer, accommodate built-in component, and contains a metal, first wiring provided in the first wiring layer and connected to the base material, and second wiring provided in the second wiring layer, and connected to the base material.SELECTED DRAWING: Figure 1

Description

The present invention relates to a wiring board, a wiring board module, and a base material.

Wiring boards with electronic components such as ICs are required to be smaller and more integrated, and electronic components may be built into the wiring board or another electronic component may be laminated on the surface layer of the wiring board. There is a tendency to adopt a wiring board that is used. In such a board, since the built-in component or the surface layer component may generate heat, it is required to design the wiring board in consideration of the heat dissipation characteristics of the built-in component or the surface layer component.

Under such circumstances, there is a technique of arranging a surface layer component above the built-in component and laminating via electrodes between the surface layer component and the built-in component and under the built-in component. With such a structure, the heat generated by the built-in component and the surface layer component is diffused to the mounting substrate under the wiring board via the via electrodes directly below each (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-067819

However, in the above structure, the heat generated from the surface layer component may pass through the internal component located below the surface layer component, and the heat generated by the surface layer component may interfere with the internal component and adversely affect the internal component. .. For example, when the amount of heat generated by the surface layer component is larger than that of the built-in component, or when the high-density mounting of the wiring board progresses, the heat generated by the surface layer component interferes with the built-in component and adversely affects the built-in component. There is. Alternatively, conversely, the heat generated by the built-in component may interfere with the surface layer component and adversely affect the surface layer component.

In view of the above circumstances, an object of the present invention is a wiring board and wiring in which mutual thermal interference between the surface layer component and the built-in component is unlikely to occur even when the surface layer component is mounted on the surface layer of the wiring board. The purpose is to provide a substrate module and a substrate.

In order to achieve the above object, the wiring board according to one embodiment of the present invention has a first main surface orthogonal to the thickness direction and a second main surface facing the first main surface.
The wiring board includes a first wiring layer provided on the first main surface side, a second wiring layer provided on the second main surface side, and the first wiring layer and the second wiring layer. A base material containing a metal that is sandwiched and capable of accommodating internal parts, a first wiring provided in the first wiring layer and connected to the base material, and a second wiring layer provided in the second wiring layer. , A second wiring connected to the base material.

According to such a wiring board, when heat is generated on the second main surface, the heat passes through a region of the base material provided apart from the built-in component and is passed through the second main surface. Heat is dissipated from the above to the first main surface. Even when the surface layer component is mounted on the surface layer of the wiring board, mutual thermal interference between the surface layer component and the built-in component is less likely to occur.

In the wiring board, the wiring provided in the second wiring layer, the region of the base material provided apart from the built-in component, and the wiring provided in the first wiring layer A heat dissipation path may be formed in which the heat is dissipated from the second main surface to the first main surface.

According to such a wiring board, the formation of the heat dissipation path makes it difficult for mutual thermal interference between the surface layer component and the built-in component to occur.

In the wiring board, the base material has an opening capable of accommodating the built-in component, and when heat is generated in the opening, the heat in the opening is the first under the opening. Another heat dissipation path may be formed to dissipate heat to the first main surface via one wiring layer.

According to such a wiring board, another heat dissipation path is formed in which the heat of the opening accommodating the built-in component is dissipated to the first main surface via the first wiring layer under the opening, so that the surface layer is formed. Thermal interference between parts and built-in parts is less likely to occur.

In the wiring board, the base material includes a first region capable of accommodating the built-in component and a second region adjacent to the first region and separated from the first region. The second region may be connected to the first wiring and the second wiring.

According to such a wiring board, the heat on the second main surface is dissipated from the second main surface to the first main surface via the second region. Since the base material has a first region capable of accommodating the built-in component and a second region separated from the first region, mutual thermal interference between the surface layer component and the built-in component occurs. It becomes difficult.

In the wiring board, the built-in component may be located between the surface layer component mounted on the second main surface and the first main surface.

According to such a wiring board, even if the built-in component is covered with the surface layer component, mutual thermal interference between the surface layer component and the built-in component is less likely to occur.

In the wiring board, at least a part of the second region may be located between the surface layer component and the first main surface.

According to such a wiring board, the second region is moved away from the built-in component, and mutual thermal interference between the surface layer component and the built-in component is less likely to occur.

In the wiring board, the second region may consist of at least two region portions.

According to such a wiring board, since the second region is composed of a plurality of regions, the heat generated by the surface layer component is more efficiently dissipated to the first main surface.

In the wiring board, the thermal conductivity of at least two regions may be different.

According to such a wiring board, even if the heat generation is uneven in the surface layer component, the thermal conductivity of the second region can be adjusted according to the respective heat distributions. As a result, mutual thermal interference between the surface layer component and the built-in component is less likely to occur.

The wiring board module according to one embodiment of the present invention includes the wiring board and surface layer components provided on the second main surface of the wiring board.

According to such a wiring board, the formation of the heat dissipation path makes it difficult for mutual thermal interference between the surface layer component and the built-in component to occur.

In the wiring board module, when the surface layer component and the wiring board are viewed from the thickness direction, the surface layer component may be contained in the wiring board.

According to such a wiring board module, the heat of the surface layer component is efficiently dissipated to the outside of the wiring board, and the heat accumulation in the surface layer component is suppressed.

The metal-containing base material according to one embodiment of the present invention is sandwiched between the wiring layers of the wiring board.
The base material has a first region capable of accommodating built-in components built in the wiring board and a second region adjacent to the first region and separated from the first region. Have.
When heat is conducted between the wiring layers, heat is conducted through the second region.

According to such a base material, the formation of the heat dissipation path makes it difficult for mutual thermal interference between the surface layer component and the built-in component to occur.

As described above, according to the present invention, even when the surface layer component is mounted on the surface layer of the wiring board, the wiring board and the wiring board module are less likely to cause mutual thermal interference between the surface layer component and the built-in component. , And a substrate is provided.

It is a schematic cross-sectional view which shows an example of the main part of the wiring board which concerns on 1st Embodiment. It is a schematic top view of the wiring board which concerns on 1st Embodiment. It is a schematic cross-sectional view which shows an example of the operation of the wiring board which concerns on 1st Embodiment. It is a schematic cross-sectional view which shows an example of the main part of the wiring board which concerns on 2nd Embodiment. It is a schematic cross-sectional view which shows an example of the main part of the wiring board which concerns on 3rd Embodiment. It is a schematic plan view which shows the layout of the core member of the 2nd region which concerns on 3rd Embodiment. It is a schematic cross-sectional view which shows an example of the main part of the wiring board which concerns on 4th Embodiment. It is a schematic cross-sectional view which shows the example of the wiring base material including a composite base material.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. XYZ axis coordinates may be introduced in each drawing. Further, the same member or a member having the same function may be designated by the same reference numeral, and the description may be omitted as appropriate after the description of the member.

(First Embodiment)

FIG. 1 is a schematic cross-sectional view showing an example of a main part of the wiring board according to the first embodiment.

The wiring board 1 includes a wiring layer 10 (first wiring layer), a wiring layer 20 (second wiring layer), and a wiring base material 30. The wiring board 1 has a main surface 1d (first main surface) orthogonal to the thickness direction and a main surface 1u (second main surface) facing the main surface 1d.

A surface layer component 50 such as an electronic component (for example, an IC chip or the like) is mounted on the wiring board 1. The surface layer component 50 is not limited to an electronic component, but may be an electrical component (for example, an inductor, a resistor, etc.). The wiring board 1 is mounted on the motherboard 60 (circuit board). The wiring board 1 may be used as an interposer, or may itself be used as a motherboard or a support board for various package components. Further, in the present embodiment, the wiring board 1 on which the surface layer component 50 is mounted is referred to as a wiring board module 1M, or is also referred to as a circuit module, an electronic device, or the like.

The wiring base material 30 is sandwiched between the wiring layer 10 and the wiring layer 20 in the thickness direction (Z-axis direction) of the wiring board 1. The wiring base material 30 extends in a direction (X-axis direction or Y-axis direction) orthogonal to the thickness direction. The wiring base material 30 includes core members 31 and 32 which are base materials containing metal, an insulating material 310, and a built-in component 40.

The core members 31 and 32 are made of, for example, a plate-like base material containing a metal. The core members 31 and 32 are sandwiched between the wiring layer 10 and the wiring layer 20. By making the core members 31 and 32 a part of the wiring board 1, the rigidity of the wiring board 1 is increased and the heat dissipation of the wiring board 1 is improved.

The core members 31 and 32 have, for example, the power supply potential, the reference potential, and the like of the IC chip when the surface layer component 50 is an IC chip. The core member 31 accommodates the built-in component 40. For the purpose of reducing the thickness of the wiring board 1, for example, the thickness of the core members 31 and 32 is set to 200 to 400 μm. The number of core members is not limited to the number shown.

For example, a base material containing a metal that forms part of the wiring base material 30 has at least one opening (cavity) 302. The opening 302 may be formed of, for example, a bottomless hole or a bottomed hole. The built-in component 40 and the insulating material 310 are housed in the opening 302. For example, the insulating material 310 is also provided between the built-in component 40 and the core member 31. As a result, electrical insulation and thermal insulation between the built-in component 40 and the core members 31 and 32 are maintained. The insulating material 310 is made of, for example, a resin material.

The built-in component 40 is, for example, an electrical component such as a capacitor, an inductor, or a register, or an electronic component such as a filter chip or an IC. The built-in component 40 is electrically connected to the vias 122 and 123 of the wiring layer 10. Further, the core member 31 arranged in the built-in component 40 is electrically connected to the via 121 or the via 124 of the wiring layer 10, and is electrically connected to the via 221 or the via 224 of the wiring layer 20. At least a part of the built-in component 40 is located between the surface layer component 50 mounted on the main surface 1u of the wiring board 1 and the main surface 1d of the wiring board 1. For example, in the example of FIG. 1, the entire built-in component 40 is covered with the upper surface layer component 50.

The wiring layer 10 has a structure in which wiring layers are laminated in the thickness direction, and is provided on the main surface 1d side of the wiring board 1. The wiring layer 10 includes an interlayer insulating layer (insulating layer) 141, vias 121 to 124, wiring layers 101 to 104 located under the group of vias 121 to 124, and vias 131 located under the group of wiring layers 101 to 104. It has wiring layers 111-114 located below the group of ~ 134 and vias 131-134. The number of each of the wiring layer and the via in the wiring layer 10, or the number of layers thereof is not limited to the example of FIG.

The interlayer insulating layer 141 is in contact with the wiring base material 30 on the lower side of the wiring base material 30. Vias 121 to 124 and 131 to 134 extend in the interlayer insulating layer 141 in the thickness direction. The wiring layers 101 to 104 are provided in the interlayer insulating layer 141. Each of the wiring layers 101 to 104 extends in a direction orthogonal to the thickness direction.

The wiring layers 111 to 114 are provided on the surface of the interlayer insulating layer 141. Each of the wiring layers 111 to 114 extends in a direction orthogonal to the thickness direction. A protective layer may be coated on each part of the wiring layers 111 to 114. The wiring layers 111 to 114 function as, for example, external connection terminals.

The via 121, the wiring layer 101, the via 131, and the wiring layer 111 are each electrically connected. The via 122, the wiring layer 102, the via 132, and the wiring layer 112 are each electrically connected. The via 123, the wiring layer 103, the via 133, and the wiring layer 113 are each electrically connected. The via 124, the wiring layer 104, the via 134, and the wiring layer 114 are each electrically connected.

Further, the wiring layer 111 is electrically connected to the wiring layer 601 of the motherboard 60 via the solder material 610, and the wiring layer 112 is electrically connected to the wiring layer 602 of the motherboard 60 via the solder material 610. The wiring layer 113 is electrically connected to the wiring layer 603 of the motherboard 60 via the solder material 610, and the wiring layer 114 is electrically connected to the wiring layer 604 of the motherboard 60 via the solder material 610. Will be done.

In the present embodiment, the wiring that electrically connects the base material containing metal as a heat dissipation path and the motherboard 60 is defined as the first wiring. For example, in the example of FIG. 1, the core member 31 corresponds to the base material containing a metal serving as a heat dissipation path, and the first wiring is vias 121, 131, wiring layers 101, 111, or vias 124, 134, It includes at least one of the wiring layers 104 and 114.

The wiring layer 20 has a structure in which wiring layers are laminated in the thickness direction, and is provided on the main surface 1u side of the wiring board 1. The wiring layer 20 includes wiring layers 201 and 204 located on the interlayer insulating layer (insulating layer) 241, vias 221 and 224, vias 221, and 224, vias 231 and 234 located on the wiring layers 201 and 204, and the like. It has wiring layers 211, 214 located above the vias 231 and 234. The number of each of the wiring layer and the via in the wiring layer 20, or the number of layers thereof is not limited to the example of FIG.

The interlayer insulating layer 241 is in contact with the wiring base material 30 on the upper side of the wiring base material 30. Vias 221, 224, 231 and 234 extend in the interlayer insulating layer 241 in the thickness direction. The wiring layers 201 and 204 are provided in the interlayer insulating layer 241. Each of the wiring layers 201 and 204 extends in a direction orthogonal to the thickness direction.

The wiring layers 211 and 214 are provided on the surface of the interlayer insulating layer 241. Each of the wiring layers 211 and 214 extends in a direction orthogonal to the thickness direction. A protective layer may be coated on a part of each of the wiring layers 211 and 214. The wiring layers 211 and 214 function as, for example, external connection terminals.

The via 221 and the wiring layer 201, the via 231 and the wiring layer 211 are each electrically connected. The via 224, the wiring layer 204, the via 234, and the wiring layer 214 are each electrically connected. Further, each of the wiring layers 211 and 214 is electrically connected to the bump electrode 501 of the surface layer component 50. When the surface layer component 50 is an electrical component having no bump electrode, each of the wiring layers 211 and 214 is electrically connected to the terminal of the electrical component.

In the present embodiment, the wiring that electrically connects the base material containing the metal as the heat dissipation path and the surface layer component 50 is referred to as the second wiring. For example, in the example of FIG. 1, the core member 31 corresponds to the base material containing a metal serving as a heat dissipation path, and the second wiring is vias 221 and 231, wiring layers 201 and 211, or vias 224 and 234. Includes at least one of wiring layers 204, 214.

In addition, the wiring board 1 may be provided with vias (not shown) that penetrate the core member 32 and electrically connect the wiring layers 10 and 20 to each other. Further, the surface layer component 50 is not limited to one, and a plurality of surface layer components 50 may be arranged on the main surface 1u. Alternatively, parts having different functions may be combined and arranged on the main surface 1u, such as a combination of electronic parts and electrical parts.

2 (a) to 2 (c) are schematic top views of the wiring board according to the first embodiment. 2 (a) to 2 (c) mainly show the outer shapes of the wiring board 1, the surface layer component 50, the core members 31, 32, the built-in component 40, and the like. The planar shapes of the core members 31 and 32 shown in FIGS. 2 (a) to 2 (c) are examples, and are not limited to these planar shapes. Each A1-A2 cross section of FIGS. 2 (a) to 2 (c) corresponds to FIG. Further, FIGS. 2A to 2C show a state in which a through hole 30t through which the via is penetrated is formed in, for example, the core member 32. The arrangement position and number of the through holes 30t are not limited to the illustrated examples, and may be changed as appropriate.

As shown in FIG. 2A, the wiring board 1 has a rectangular shape. When the wiring board 1 is viewed from the Z-axis direction, for example, the area of the surface layer component 50 is larger than the area of the built-in component 40. The surface layer component 50 is housed in the wiring board 1.

The built-in component 40 is surrounded by the core member 31 via an insulating material 310 in a plane (XY-axis plane) perpendicular to the thickness direction. Alternatively, as shown in FIG. 2 (b), the core member 31 may have a shape in which one side of the built-in component 40 is open in the plane, and as shown in FIG. 2 (c), the core member 31 is built in the plane. It may have a shape that sandwiches the component 40.

However, an insulating material 310 is provided between the built-in component 40 and the core member 31, so that the built-in component 40 and the core member 31 are electrically disconnected and thermally insulated.

The materials of the core members 31 and 32 may be, for example, copper or the composite base material illustrated in FIG. The material of each wiring layer and each via is, for example, copper, aluminum, or the like. The materials of the insulating material 310 and the interlayer insulating layers 141 and 241 are ceramics, thermosetting resins and the like.

The operation of the wiring board 1 will be described. FIG. 3 is a schematic cross-sectional view showing an example of the operation of the wiring board according to the first embodiment.

In the present embodiment, the core member 31 electrically connected to the surface layer component 50 is provided apart from the built-in component 40. As a result, when the surface layer component 50 generates heat on the main surface 1u of the wiring board 1, the heat passes through the region of the base material containing metal provided apart from the built-in component 40, that is, the core member 31. Then, heat is dissipated from the main surface 1u to the main surface 1d of the wiring board 1. The motherboard 60 functions as a heat dissipation substrate that receives this heat.

For example, in the wiring board 1, the vias 221 and 231 provided in the wiring layer 20, the metal wiring composed of the wiring layers 201 and 211, the core member 31, and the vias 121 and 131 provided in the wiring layer 10 The metal wiring composed of the wiring layers 101 and 111 forms a heat dissipation path in which the heat generated by the surface layer component 50 is dissipated from the main surface 1u to the main surface 1d.

Similarly, in the wiring board 1, the vias 224 and 234 provided in the wiring layer 20, the metal wiring composed of the wiring layers 204 and 214, the core member 31, and the vias 124 provided in the wiring layer 10 The metal wiring composed of 134, the wiring layers 104, and 114 forms a heat dissipation path in which the heat generated by the surface layer component 50 is dissipated from the main surface 1u to the main surface 1d.

As a result, the heat generated by the surface layer component 50 is efficiently dissipated to the motherboard 60 by the heat dissipation path via the core member 31. The heat flow through this heat dissipation path is indicated by the arrow T2. In particular, when the surface layer component 50 is an IC chip, the heat generated by the surface layer component 50 is efficiently dissipated to the motherboard 60 by connecting the wiring layers 211 and 214 to the power supply potential terminal, the reference potential terminal, and the like of the surface layer component 50. NS. Alternatively, when the surface layer component 50 is an inductor or the like, the lead wire of the surface layer component 50 is connected to the wiring layers 211 and 214, so that the heat generated by the surface layer component 50 is efficiently dissipated to the motherboard 60.

On the other hand, when heat is generated in the built-in component 40 provided in the opening 302, the heat passes through the wiring layer 10 under the opening 302 accommodating the built-in component 40, and the main surface 1d of the wiring board 1 Heat is dissipated to.

For example, in the wiring board 1, a metal wiring composed of vias 122 and 132 and wiring layers 102 and 112 provided in the wiring layer 20, or a metal wiring composed of vias 123 and 133 and wiring layers 103 and 113. As a result, a heat dissipation path is formed in which the heat generated by the built-in component 40 is dissipated from the built-in component 40 to the main surface 1d.

As a result, the heat generated by the built-in component 40 is efficiently dissipated to the motherboard 60 by the heat dissipation path via the via and the wiring layer under the built-in component 40. The heat flow through this heat dissipation path is indicated by the arrow T1.

As described above, in the present embodiment, by separating the heat dissipation path of heat generated from the surface layer component 50 and the heat dissipation path of heat generated from the built-in component 40, the surface layer component 50 causes thermal interference with the built-in component 40. Alternatively, thermal interference of the built-in component 40 with the surface layer component 50 is suppressed. As a result, a highly reliable wiring board 1 is realized.

For example, the core member 31 contains a metal and has excellent thermal conductivity. Further, the volume of the core member 31 is large. As a result, the heat generated by the surface layer component 50 is efficiently dissipated to the motherboard 60 via the core member 31 provided between the wiring layers 10 and 20.

For example, in the case of a configuration in which the temperature of the surface layer component 50 is higher than the temperature of the built-in component 40 when the wiring board module 1M is driven, the heat generated by the surface layer component 50 is a core member provided between the wiring layers 10 and 20. The heat is efficiently dissipated to the motherboard 60 via 31. As a result, heat interference with the built-in component 40 is suppressed.

Further, an insulating material 310 having low thermal conductivity is interposed between the built-in component 40 and the core member 31. As a result, heat conduction from the core member 31 to the built-in component 40 is suppressed.

Further, if the surface layer component 50 is configured to fit in the wiring board 1 without protruding from the wiring board 1, the heat generated by the surface layer component 50 is efficiently dissipated to the motherboard 60 via the core member 31. As a result, so-called heat accumulation in the surface layer component 50 is avoided.

Further, the heat dissipation path for radiating the heat of the surface layer component 50 and the heat dissipation path for radiating the heat of the built-in component 40 are not limited to the heat conduction path, but are used as an electric circuit for transmitting an electric signal or supplying electric power. You may. By using the heat conduction path and the electric circuit together, the size increase of the wiring board 1 can be suppressed.

Further, since the core member 31 for accommodating the built-in component 40 and the core member 31 for dissipating heat from the surface layer component 50 are shared, an increase in the size of the wiring board 1 can be suppressed.

(Second Embodiment)

The heat generated by the surface layer component 50 is not limited to the embodiment in which heat is dissipated via the core member arranged directly under the surface layer component 50, and the heat generated by the surface layer component 50 is passed through the core member arranged partially offset from the surface layer component 50 to pass through the motherboard 60. You may dissipate heat to. FIG. 4 is a schematic cross-sectional view showing an example of a main part of the wiring board according to the second embodiment.

In the wiring board 2 shown in FIG. 4, the built-in component 40 is located between the surface layer component 50 mounted on the main surface 1u of the wiring board 2 and the main surface 1d of the wiring board 2. The core member of the wiring board 2 includes a region 30a (first region) capable of accommodating the built-in component 40 and a region 30b (second region) adjacent to the region 30a and separated from the region 30a. have. For example, in FIG. 4, the region 30a corresponds to the core member 31, and the region 30b corresponds to the core member 32.

In the wiring board 2, at least a part of the region 30b is located between the surface layer component 50 and the main surface 1d. That is, the core member 32 projects so as to keep the built-in component 40 away from between the surface layer component 50 and the main surface 1d. Further, an insulating material 310 is provided between the core member 31 and the core member 32.

In the second embodiment, the first wiring includes, for example, at least one of vias 125, 135 and wiring layers 105, 115, and the second wiring includes, for example, at least one of vias 223, 235 and wiring layers 205, 215. Including. Further, the core member 32 corresponds to the base material containing a metal serving as a heat dissipation path.

With such a configuration, the heat generated by the surface layer component 50 on the main surface 1u of the wiring board 2 is dissipated from the main surface 1u to the main surface 1d via the core member 32 (region 30b). The heat flow through this heat dissipation path is indicated by the arrow T3.

For example, in the wiring board 2, the vias 225 and 235 provided in the wiring layer 20, the metal wiring composed of the wiring layers 205 and 215, the core member 32, and the vias 125 and 135 provided in the wiring layer 10 The metal wiring made of the wiring layers 105 and 115 forms a heat dissipation path in which the heat generated by the surface layer component 50 is dissipated from the main surface 1u to the main surface 1d.

In this way, in the wiring board 2, by separating the heat dissipation path of heat generated from the surface layer component 50 and the heat dissipation path of heat generated from the built-in component 40, the surface layer component 50 causes thermal interference with the built-in component 40. Alternatively, thermal interference of the built-in component 40 with the surface layer component 50 is suppressed.

In particular, in the wiring board 2, a part of the core member 32 through which the heat generated from the surface layer component 50 passes protrudes from between the surface layer component 50 and the main surface 1d so as to move the built-in component 40 away from the surface layer component 50. The heat dissipation path of heat generated from 50 and the heat dissipation path of heat generated from the built-in component 40 are further separated. As a result, the thermal interference of the surface layer component 50 with the built-in component 40 or the thermal interference of the built-in component 40 with the surface layer component 50 is further suppressed.

Not limited to the embodiment in which the built-in component 40 is positioned between the surface layer component 50 and the main surface 1d of the wiring board 2, the internal component 40 is located between the surface layer component 50 and the main surface 1d of the wiring board 2 in the wiring board 2. An example in which the built-in component 40 is not provided is also included in the present embodiment.

With such a configuration, since the surface layer component 50 is not located above the built-in component 40, the built-in component 40 is less susceptible to the heat generated by the surface layer component 50.

(Third Embodiment)

The region of the core member through which the heat generated by the surface layer component 50 passes is not limited to one, and may be a plurality of regions. FIG. 5 is a schematic cross-sectional view showing an example of a main part of the wiring board according to the third embodiment.

In the wiring board 3 shown in FIG. 5, the region 30b is composed of at least two region portions. For example, the region 30b has a region 30b-1 and a region 30b-2.

For example, in the region 30b-1 of the wiring board 3, the vias 226 and 236 provided in the wiring layer 20, the metal wiring composed of the wiring layers 206 and 216, the core member 32, and the wiring layer 10 are provided. The metal wiring composed of the vias 126, 136 and the wiring layers 106, 116 forms a heat dissipation path in which the heat generated by the surface layer component 50 is dissipated from the main surface 1u to the main surface 1d.

On the other hand, in the region 30b-2 of the wiring board 3, the vias 225 and 235 provided in the wiring layer 20, the metal wiring composed of the wiring layers 205 and 215, the core member 32, and the wiring layer 10 are provided. The metal wiring composed of the vias 125 and 135 and the wiring layers 105 and 115 forms a heat dissipation path in which the heat generated by the surface layer component 50 is dissipated from the main surface 1u to the main surface 1d.

In the third embodiment, the first wiring includes, for example, at least one of vias 125, 135, wiring layers 105, 115, or vias 126, 136, wiring layers 106, 116, and the second wiring is, for example, Includes at least one of vias 223, 235, wiring layers 205, 215, or vias 226, 236, wiring layers 206, 216.

With such a configuration, since a plurality of core members 32 through which heat generated from the surface layer component 50 passes are arranged, the heat dissipation effect is further increased. As a result, the thermal interference of the surface layer component 50 with the built-in component 40 or the thermal interference of the built-in component 40 with the surface layer component 50 is further suppressed.

Further, the thermal conductivity of the core member 32 arranged in the region 30b-1 and the core member 32 arranged in the region 30b-2 may be different.

For example, in the surface layer component 50, when the amount of heat generated varies and the amount of heat conduction of the core member 32 arranged in the area 30b-2 is larger than that of the core member 32 arranged in the area 30b-1, the area 30b- The thermal conductivity of the core member 32 arranged in the region 30b-2 is set higher than the thermal conductivity of the core member 32 arranged in 1. For example, when the core member 32 of the region 30b-1 is made of copper, the core member 32 of the region 30b-2 is made of a carbon material such as silver, graphite, or carbon nanotube. In this way, the material may be changed according to each region.

With such a configuration, even if there is a difference in the amount of heat generated in the surface layer component 50, by adjusting the thermal conductivity of each core member 32, the heat generated by the surface layer component 50 is more evenly generated in the motherboard 60. Is dissipated to. Alternatively, when surface layer components having different functions are combined, the core member 32 having a higher thermal conductivity may be electrically connected to the surface layer component having a larger calorific value.

6 (a) to 6 (c) are schematic plan views showing the layout of the core member of the second region according to the third embodiment.

The layout of the core member 32 is not particularly limited, and may be, for example, a layout in which two core members 32 are arranged in parallel as shown in FIG. 6 (a), and as shown in FIG. 6 (b), L The character-shaped core member 32 may be arranged, or as shown in FIG. 6C, the layout may be arranged at the four corners of the wiring board 3.

Further, the volumes of the plurality of core members 32 do not have to be the same, and when there is a difference in the amount of heat generated in the surface layer component 50, or when surface layer components having different functions are combined, the amount of heat generated in each surface layer component is increased. If they are different, the core member 32 having a larger volume may be arranged in the region where the amount of heat generated is large.

(Fourth Embodiment)

FIG. 7 is a schematic cross-sectional view showing an example of a main part of the wiring board according to the fourth embodiment.

In the wiring board 4 shown in FIG. 7, the core member 32 of the region 30b is arranged not between the surface layer component 50 and the main surface 1d of the wiring board 4, but apart from between the surface layer component 50 and the main surface 1d. There is.

With such a configuration, the heat dissipation path (arrow T4) through which the heat generated by the surface layer component 50 is dissipated is further separated from the built-in component 40, and the surface layer component 50 interferes with the built-in component 40 or the built-in component 40. Thermal interference with the surface layer component 50 is further suppressed.

(Core member)

The core members 31 and 32 according to the first to fourth embodiments are base materials containing a metal. The material of the core members 31 and 32 may be composed of a simple substance of copper, silver, or a carbon material. It may be the composite base material shown in FIGS. 8A and 8B. 8 (a) and 8 (b) show an example of a wiring base material including a composite base material.

For example, as shown in FIG. 8A, the core member 31 may have a structure in which the metal material 312 as an intermediate layer is sandwiched between metal materials 311 which are different from the metal material 312 in the thickness direction. .. Similarly, the core member 32 may have a structure in which the metal material 322, which is an intermediate layer, is sandwiched between metal materials 321 which are different from the metal material 322 in the thickness direction.

For example, if the metal materials 311 and 321 are made of copper, the metal materials 312 and 322 are made of, for example, silver.

Further, as shown in FIG. 8B, the core member 31 may have a structure in which the carbon material 313 is sandwiched between the metal materials 311 in the thickness direction. Similarly, the core member 32 may have a structure in which the carbon material 323 is sandwiched between the metal materials 321 in the thickness direction.

Examples of the carbon material 313 and 323 include carbon materials such as carbon nanotubes and graphite. In particular, when carbon nanotubes are selected as the carbon materials 313 and 323, the thermal conductivity of the carbon nanotubes is about 10 times that of copper, so that the heat dissipation effect is higher than that of a metal substrate containing only copper. To increase.

Further, when graphite is selected as the carbon material 313 or 323, the anisotropy of the thermal conductivity of graphite can be utilized. For example, if graphite is arranged so that the direction of higher thermal conductivity and the thickness direction are parallel, the heat dissipation effect in the thickness direction is promoted, and the direction of higher thermal conductivity and the main surfaces 1d and 1u are parallel. If the graphite is arranged so as to be, the heat dissipation effect in the direction orthogonal to the thickness direction is promoted. In this way, the direction of heat dissipation can be guided in a specific direction.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made. Each embodiment is not limited to an independent form and can be combined as technically possible as possible.

1, 2, 3, 4 ... Wiring board 1M ... Wiring board module 10, 20 ... Wiring layer 30 ... Wiring base material 30a, 30b, 30b-1, 30b-2 ... Region 30t ... Through hole 31, 32 ... Core member 40 ... Built-in parts 50 ... Surface parts 60 ... Mothers 101, 102, 103, 104, 111, 112, 113, 114 ... Wiring layers 121, 122, 123, 124, 131, 132, 133, 134 ... Via 141 ... Interlayer insulation layer 201, 204, 211, 214 ... Wiring layer 221 ... 224, 231, 234 ... Via 241 ... Interlayer insulation layer 302 ... Opening 310 ... Insulation material 311, 312 ... Metal material 313 ... Carbon material 501 ... Bump electrode 601, 602, 603, 604 ... Wiring layer 610 ... Solder material

Claims (11)

A wiring board having a first main surface orthogonal to the thickness direction and a second main surface facing the first main surface.
The first wiring layer provided on the first main surface side and
The second wiring layer provided on the second main surface side and
A base material containing a metal sandwiched between the first wiring layer and the second wiring layer and capable of accommodating internal parts, and
The first wiring provided in the first wiring layer and connected to the base material, and
A second wiring provided in the second wiring layer and connected to the base material, and
Wiring board. The wiring board according to claim 1.
The heat is generated by the second main component due to the wiring provided in the second wiring layer, the area of the base material provided apart from the built-in component, and the wiring provided in the first wiring layer. A wiring board in which a heat dissipation path is formed to dissipate heat from a surface to the first main surface. The wiring board according to claim 1 or 2.
The substrate has an opening capable of accommodating the built-in component.
A wiring board formed with another heat dissipation path in which when heat is generated in the opening, the heat in the opening is dissipated to the first main surface via the first wiring layer under the opening. The wiring board according to any one of claims 1 to 3.
The base material has a first region capable of accommodating the built-in component and a second region adjacent to the first region and provided apart from the first region.
A wiring board in which the second region is connected to the first wiring and the second wiring. The wiring board according to any one of claims 1 to 4.
A wiring board in which the built-in component is located between a surface layer component mounted on the second main surface and the first main surface. The wiring board according to claim 4 or 5.
A wiring board in which at least a part of the second region is located between the surface layer component and the first main surface. The wiring board according to any one of claims 4 to 6.
The second region is a wiring board composed of at least two region portions. The wiring board according to claim 7.
Wiring boards having different thermal conductivity in at least two regions. The wiring board according to any one of claims 1 to 8.
A wiring board module including a surface layer component provided on the second main surface of the wiring board. The wiring board module according to claim 9.
When the surface layer component and the wiring board are viewed from the thickness direction,
A wiring board module in which the surface layer component is housed in the wiring board. A base material containing metal sandwiched between wiring layers of a wiring board.
It has a first region capable of accommodating built-in components built in the wiring board, and a second region adjacent to the first region and provided apart from the first region.
A base material that conducts heat through the second region when heat is conducted between the wiring layers.

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