CN117199034A - Circuit substrate and circuit module - Google Patents

Abstract

The present invention relates to a circuit board and a circuit module, which inhibit the connection between a first external electrode of a first electronic component and a first connection conductor penetrating a resin member from being disconnected or inhibit the connection between a second external electrode of a second electronic component and a second connection conductor penetrating the resin member from being disconnected. The first circuit substrate comprises a first mounting electrode and a second mounting electrode. The second lower main surface of the resin member is in contact with the first upper main surface of the first circuit board. A first through hole and a second through hole are provided to penetrate the cover member in the up-down direction. The third lower main surface of the cover member is in contact with the second upper main surface of the resin member. The first connection conductor and the second connection conductor penetrate the resin member in the up-down direction. The lower ends of the first connecting conductor and the second connecting conductor are respectively connected with the first mounting electrode and the second mounting electrode. A portion of the first connection conductor and a portion of the second connection conductor are located in the first through hole and the second through hole, respectively. The cover member has a linear expansion coefficient smaller than that of the resin member.

Description

Circuit substrate and circuit module

Technical Field

The present invention relates to a circuit board on which electronic components are mounted.

Background

As an invention related to a conventional circuit module, for example, a three-dimensional package structure described in patent document 1 is known. The package structure is provided with: semiconductor package, energy storage element, first electrode, second electrode, first conductivity element, second conductivity element, first copper pillar, second copper pillar.

The semiconductor package has an upper surface and a lower surface. The first conductive element and the second conductive element are provided on the lower surface of the semiconductor package. The first copper pillar penetrates the semiconductor package in the up-down direction. The lower end of the first copper pillar is connected to the first conductive element. The second copper pillar penetrates the semiconductor package in the up-down direction. The lower end of the second copper pillar is connected to the second conductive element.

The first electrode and the second electrode are disposed on a surface of the energy storage element. The first electrode is connected with the upper end of the first copper column. The second electrode is connected with the upper end of the second copper column. Thus, the first electrode is electrically connected to the first conductive element via the first copper pillar. The second electrode is electrically connected to the second conductive element via the second copper pillar.

Patent document 1: U.S. patent application publication No. 2013/0001756 (FIG. 3B)

However, when the three-dimensional package structure described in patent document 1 is used, for example, the energy storage element generates heat. In this case, the semiconductor package and the energy storage element expand due to heat generated by the energy storage element. However, the linear expansion coefficient of the semiconductor package is greater than the linear expansion coefficient of the energy storage element. Therefore, the distance between the first copper pillar and the second copper pillar is larger than the distance between the first electrode and the second electrode. As a result, the solder connecting the first copper pillar and the first electrode may be broken.

Disclosure of Invention

Accordingly, an object of the present invention is to provide a circuit board and a circuit module capable of suppressing disconnection between a first external electrode of a first electronic component and a first connection conductor penetrating a resin member or disconnection between a second external electrode of a second electronic component and a second connection conductor penetrating the resin member.

A circuit board according to an aspect of the present invention includes:

a first circuit board including a first circuit board main body having a first upper main surface and a first lower main surface arranged in a vertical direction, and first mounting electrodes and second mounting electrodes located on the first upper main surface;

a resin member having a second upper main surface and a second lower main surface arranged in the vertical direction, the second lower main surface being in contact with the first upper main surface;

a cover member having a third upper main surface and a third lower main surface arranged in the vertical direction, and provided with a first through hole and a second through hole penetrating the cover member in the vertical direction, wherein the third lower main surface is in contact with the second upper main surface;

a first connection conductor penetrating the resin member in a vertical direction, a lower end of the first connection conductor being connected to the first mounting electrode, a portion of the first connection conductor being located in the first through hole; and

a second connection conductor penetrating the resin member in the vertical direction, wherein a lower end of the second connection conductor is connected to the second mounting electrode, a part of the second connection conductor is positioned in the second through hole,

in the first through hole, at least a part of the periphery of the first connection conductor is present with the resin member when seen downward,

in the second through hole, at least a part of the periphery of the second connection conductor is present with the resin member when seen downward,

the cover member has a linear expansion coefficient smaller than that of the resin member.

According to the circuit board of the present invention, it is possible to suppress disconnection between the first external electrode of the first electronic component and the first connection conductor of the resin member or disconnection between the second external electrode of the second electronic component and the second connection conductor of the resin member.

Drawings

Fig. 1 is a perspective view of a circuit module 1.

Fig. 2 is a cross-sectional view at A-A of the circuit module 1.

Fig. 3 is a top view of the circuit module 1.

Fig. 4 is a plan view of the circuit board 10 a.

Fig. 5 is a plan view of the circuit board 10 b.

Description of the reference numerals

1 … circuit module; 10. 10a, 10b … circuit substrates; 12 … first circuit substrate; 14 … resin member; 14a … first external electrode; 14b … second external electrode; 16 … cover member; 18a … first connecting conductors; 18b … second connecting conductors; 20 … second electronic component; 30 … first electronic component; 32 … component body; 34a … first external electrode; 34b … second external electrode; 122 … first circuit substrate body; 124a … first mounting electrode; 124b … second mounting electrode; 126a, 126b … mount electrodes; ha … first through hole; hb … second via; hc … third via; s1 … first upper major face; s11 … second upper major face; s12 … second lower major face; s2 … first lower major face; s21 … third upper major face; s22 … third lower major surface.

Detailed Description

(embodiment)

[ Structure of Circuit Module ]

The structure of the circuit module 1 according to the embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a perspective view of a circuit module 1. Fig. 2 is a cross-sectional view at A-A of the circuit module 1. Fig. 3 is a top view of the circuit module 1.

In this specification, the direction is defined as follows. The direction in which the first upper main surface S1 and the first lower main surface S2 of the first circuit substrate main body 122 are aligned is defined as the up-down direction. The direction orthogonal to the up-down direction is defined as the left-right direction and the front-back direction. The left-right direction is orthogonal to the front-rear direction. In the present embodiment, the vertical direction, the front-rear direction, and the left-right direction may be different from the vertical direction, the front-rear direction, and the left-right direction when the circuit module 1 is used.

Hereinafter, X is a component or member of the circuit module 1. In the present specification, unless otherwise specified, each part of X is defined as follows. The front of X means the front half of X. The rear of X means the rear half of X. The left part of X means the left half of X. The right part of X means the right half of X. The upper part of X means the upper half of X. The lower part of X means the lower half of X. The front end of X means the front end of X. The rear end of X means the end of X rearward. The left end of X means the left end of X. The right end of X means the right end of X. The upper end of X means the upper end of X. The lower end of X means the lower end of X. The front end of X means the front end of X and its vicinity. The rear end of X means the rear end of X and its vicinity. The left end of X means the left end of X and its vicinity. The right end of X means the right end of X and its vicinity. The upper end of X means the upper end of X and its vicinity. The lower end of X means the lower end of X and its vicinity.

The circuit module 1 is used for electronic equipment such as a smart phone. As shown in fig. 1, the circuit module 1 includes a circuit board 10 and a first electronic component 30. The circuit board 10 includes: the first circuit board 12, the resin member 14, the cover member 16, the first connection conductor 18a, the second connection conductor 18b, and the second electronic component 20 (see fig. 2).

As shown in fig. 2, the first circuit substrate 12 includes: a first circuit substrate body 122, a first mounting electrode 124a, a second mounting electrode 124b, and mounting electrodes 126a, 126b. The first circuit board main body 122 has a first upper main surface S1 and a first lower main surface S2 arranged in the up-down direction. The material of the first circuit substrate main body 122 is, for example, glass epoxy resin. A circuit is provided on the surface and inside of the first circuit board main body 122 through a conductor layer, not shown. The first mounting electrode 124a, the second mounting electrode 124b, and the mounting electrodes 126a, 126b are located on the first upper main surface S1. In the present embodiment, the first mounting electrode 124a, the mounting electrodes 126a, 126b, and the second mounting electrode 124b are arranged in this order from left to right.

The second electronic component 20 is, for example, an IC (Integrated Circuit: integrated circuit). The second electronic component 20 generates heat during operation. The second electronic component 20 is mounted on the first upper main surface S1. More specifically, the second electronic component 20 is fixed to the mounting electrodes 126a and 126b by solder (not shown).

The resin member 14 has a second upper main surface S11 and a second lower main surface S12 arranged in the up-down direction. The resin member 14 is located on the first circuit substrate 12. The second lower main surface S12 is in contact with the first upper main surface S1. Thereby, the resin member 14 covers the first upper main surface S1 of the first circuit substrate 12. The resin member 14 covers the front, rear, left, and right surfaces of the second electronic component 20. The material of such a resin member 14 is, for example, epoxy resin.

The cover member 16 has a third upper main surface S21 and a third lower main surface S22 aligned in the up-down direction. The cover member 16 is located on the resin member 14 and the second electronic component 20. The third lower main surface S22 is in contact with the second upper main surface S11. Thereby, the cover member 16 covers the resin member 14.

The cover member 16 is provided with a first through hole Ha and a second through hole Hb penetrating the cover member 16 in the up-down direction. The first through hole Ha and the second through hole Hb have a circular shape when seen downward. The first through holes Ha and the second through holes Hb are arranged in this order from left to right.

The cover member 16 has a linear expansion coefficient smaller than that of the resin member 14. Thus, the absolute value of the difference between the linear expansion coefficient of the cover member 16 and the linear expansion coefficient of the component main body 32 (described later) is smaller than the absolute value of the difference between the linear expansion coefficient of the resin member 14 and the linear expansion coefficient of the component main body 32. In the present specification, the linear expansion coefficient means a ratio of a change in length according to an increase in temperature.

Further, the linear expansion coefficient in the solid state (glass transition temperature or lower) is different from that in the molten state. The linear expansion coefficient in this specification is a solid state linear expansion coefficient. However, the linear expansion coefficient of the cover member 16 may be higher than the linear expansion coefficient of the resin member 14 in the solid state and lower than the linear expansion coefficient of the resin member 14 in the molten state. In addition, the cover member 16 has conductivity. The material of the cover member 16 is carbon fiber reinforced plastic. In this case, the thermal conductivity of the cover member 16 is higher than that of the resin member 14.

The first connection conductor 18a has a cylindrical shape having a central axis extending in the up-down direction. The first connection conductor 18a penetrates the resin member 14 in the up-down direction. The lower end of the first connection conductor 18a is connected to the first mounting electrode 124a. The lower end of the first connection conductor 18a is fixed to the first mounting electrode 124a by, for example, solder (not shown). A portion of the first connection conductor 18a is located in the first through hole Ha. In the present embodiment, the upper portion of the first connection conductor 18a is located in the first through hole Ha. Also, in the first through hole Ha, there is a resin member 14 at least at a part of the periphery of the first connection conductor 18a when seen downward. In the present embodiment, the resin member 14 is present in the first through hole Ha so as to surround the circumference of the first connection conductor 18a by one circle when seen downward. Thereby, the first connection conductor 18a is not in contact with the cover member 16. Thus, the first connection conductor 18a is not electrically connected to the cover member 16. In addition, the upper end of the first connection conductor 18a is exposed from the circuit board 10.

The second connection conductor 18b has a cylindrical shape having a central axis extending in the up-down direction. The second connection conductor 18b penetrates the resin member 14 in the up-down direction. The lower end of the second connection conductor 18b is connected to the second mounting electrode 124b. The lower end of the second connection conductor 18b is fixed to the second mounting electrode 124b by, for example, solder (not shown). A portion of the second connection conductor 18b is located within the second through hole Hb. In the present embodiment, the upper portion of the second connection conductor 18b is located in the second through hole Hb. Also, in the second through hole Hb, there is a resin member 14 at least in a part of the periphery of the second connection conductor 18b when seen downward. In the present embodiment, the resin member 14 is present in the second through hole Hb so as to surround the circumference of the second connection conductor 18b by one turn when seen downward. Thereby, the second connection conductor 18b is not in contact with the cover member 16. Thus, the second connection conductor 18b is not electrically connected to the cover member 16. In addition, the upper end of the second connection conductor 18b is exposed from the circuit board 10. The material of the first connection conductor 18a and the material of the second connection conductor 18b described above are metals. The metal is copper, for example.

The first electronic component 30 is a component that generates heat during operation. The first electronic component 30 is, for example, an inductor. The first electronic component 30 includes: a component body 32, a first external electrode 34a, and a second external electrode 34b. The member main body 32 has a rectangular parallelepiped shape. The first external electrode 34a and the second external electrode 34b are provided on the surface of the component main body 32. In the present embodiment, the first external electrode 34a is provided on the lower surface and the left side of the component main body 32. The second external electrode 34b is provided on the lower surface and right of the component main body 32.

The first electronic component 30 as described above is mounted on the circuit board 10. In more detail, the first external electrode 34a is connected to the upper end of the first connection conductor 18 a. In the present embodiment, the first external electrode 34a is fixed to the upper end of the first connection conductor 18a by solder (not shown). At this time, as shown in fig. 3, the first external electrode 34a is received in the outer edge of the first through hole Ha when seen downward. Thus, the first external electrode 34a is not electrically connected to the cover member 16. The second external electrode 34b is connected to the upper end of the second connection conductor 18 b. In the present embodiment, the second external electrode 34b is fixed to the upper end of the second connection conductor 18b by solder (not shown). At this time, as shown in fig. 3, the second external electrode 34b is housed in the outer edge of the second through hole Hb when seen downward. Thereby, the second external electrode 34b is not electrically connected to the cover member 16.

[ Effect ]

According to the circuit board 10, disconnection between the first external electrode 34a and the first connection conductor 18a or disconnection between the second external electrode 34b and the second connection conductor 18b can be suppressed. In more detail, when the circuit module 1 is in use, the first electronic component 30 generates heat. Thereby, the first electronic component 30 and the circuit board 10 thermally expand.

Therefore, the cover member 16 has a linear expansion coefficient smaller than that of the resin member 14. Thus, the absolute value of the difference between the linear expansion coefficient of the cover member 16 and the linear expansion coefficient of the component main body 32 (described later) is smaller than the absolute value of the difference between the linear expansion coefficient of the resin member 14 and the linear expansion coefficient of the component main body 32. Therefore, the cover member 16 is difficult to extend in the left-right direction. Accordingly, the first connection conductor 18a and the second connection conductor 18b are held by the cover member 16. As a result, the distance between the first connection conductor 18a and the second connection conductor 18b is suppressed from being excessively large compared with the distance between the first external electrode 34a and the second external electrode 34b. As described above, according to the circuit board 10, disconnection between the first external electrode 34a and the first connection conductor 18a or disconnection between the second external electrode 34b and the second connection conductor 18b can be suppressed.

In the circuit substrate 10, the resin member 14 exists in at least a part of the periphery of the first connection conductor 18a within the first through hole Ha when seen downward. Thereby, the resin member 14 is closely contacted with the upper portion of the first connection conductor 18 a. Thereby, the first connection conductor 18a is held by the resin member 14. Thus, the first connection conductor 18a is restrained from moving within the resin member 14, and the first connection conductor 18a is restrained from being detached from the resin member 14.

According to the circuit board 10, the first connection conductor 18a and the second connection conductor 18b are suppressed from tilting. More specifically, in manufacturing the circuit board 10, the molten resin is injected into a mold to form the resin member 14. Since the melted resin is in a high temperature state, the first circuit substrate 12 is heated. Thereby, the first circuit substrate 12 extends in the left-right direction. At this time, the first connection conductor 18a and the second connection conductor 18b may be inclined. Therefore, the cover member 16 has a linear expansion coefficient smaller than that of the resin member 14. Therefore, the cover member 16 is difficult to extend in the left-right direction. As a result, the inclination of the first connection conductor 18a and the second connection conductor 18b is suppressed in the circuit board 10.

In the circuit board 10, the cover member 16 has conductivity. Thereby, the cover member 16 functions as a shield.

In the circuit substrate 10, the thermal conductivity of the cover member 16 is higher than that of the resin member 14. Thus, the heat generated in the circuit board 10 is easily radiated to the outside of the circuit board 10 through the cover member 16.

(modification)

The circuit boards 10a and 10b according to the modification will be described below with reference to the drawings. Fig. 4 is a plan view of the circuit board 10 a. Fig. 5 is a plan view of the circuit board 10 b.

As shown in fig. 4, the circuit board 10a is provided with a plurality of third through holes Hc penetrating the cover member 16 in the vertical direction. The plurality of third through holes Hc have a circular shape when seen downward. The resin member 14 is present in the plurality of third through holes Hc. Further, as shown in fig. 5, the plurality of third through holes Hc may have a shape other than a circular shape when seen downward. In the circuit substrate 10b, the plurality of third through holes Hc have a quadrangular shape and a triangular shape when seen downward. According to the circuit boards 10a, 10b, the melted resin can flow between the first circuit board 12 and the cover member 16 via the plurality of third through holes Hc.

(other embodiments)

The circuit board according to the present invention is not limited to the circuit boards 10, 10a, and 10b, and may be modified within the scope of the gist thereof. The circuit boards 10, 10a, and 10b may be combined in any manner.

The material of the cover member 16 is not limited to carbon fiber reinforced plastic, and may be, for example, metal such as aluminum.

The cover member 16 may have insulation. In this case, the first external electrode 14a may not be housed in the outer edge of the first through hole Ha when seen downward. The second external electrode 14b may not be housed in the outer edge of the second through hole Hb when seen downward.

The thermal conductivity of the cover member 16 may be equal to or lower than the thermal conductivity of the resin member 14.

The circuit board 10 may not include the second electronic component 20.

The present invention has the following structure.

(1) A circuit substrate, comprising:

a first circuit board including a first circuit board main body having a first upper main surface and a first lower main surface arranged in a vertical direction, and first mounting electrodes and second mounting electrodes located on the first upper main surface;

a resin member having a second upper main surface and a second lower main surface arranged in the vertical direction, the second lower main surface being in contact with the first upper main surface;

a cover member having a third upper main surface and a third lower main surface arranged in the vertical direction, and provided with a first through hole and a second through hole penetrating the cover member in the vertical direction, wherein the third lower main surface is in contact with the second upper main surface;

a first connection conductor penetrating the resin member in a vertical direction, a lower end of the first connection conductor being connected to the first mounting electrode, a portion of the first connection conductor being located in the first through hole; and

a second connection conductor penetrating the resin member in the vertical direction, wherein a lower end of the second connection conductor is connected to the second mounting electrode, a part of the second connection conductor is positioned in the second through hole,

in the first through hole, at least a part of the periphery of the first connection conductor is present with the resin member when seen downward,

in the second through hole, at least a part of the periphery of the second connection conductor is present with the resin member when seen downward,

the cover member has a linear expansion coefficient smaller than that of the resin member.

(2) The circuit substrate according to (1), wherein,

the cover member has a higher thermal conductivity than the resin member.

(3) The circuit substrate according to (1) or (2), wherein,

the material of the cover member is carbon fiber reinforced plastic.

(4) The circuit board according to any one of (1) to (3), wherein,

the circuit board further includes a second electronic component mounted on the first upper main surface.

(5) The circuit board according to any one of (1) to (4), wherein,

a third through hole penetrating the cover member in the up-down direction,

the resin member is provided in the third through hole.

(6) A circuit module is provided with:

(1) The circuit board according to any one of (5); and

a first electronic component including a component main body, and a first external electrode and a second external electrode provided on a surface of the component main body,

the first external electrode is connected to the upper end of the first connection conductor,

the second external electrode is connected to an upper end of the second connection conductor.

(7) The circuit module according to (6), wherein,

the cover member has an electrical conductivity such that,

the resin member is present in the first through hole so as to surround the periphery of the first connection conductor when seen downward.

(8) The circuit module according to (7), wherein,

when seen downwards, the first external electrode is accommodated in the outer edge of the first through hole,

the second external electrode is received in an outer edge of the second through hole when seen downward.

Claims (8)

1. A circuit substrate, comprising:

a first circuit board including a first circuit board main body having a first upper main surface and a first lower main surface arranged in a vertical direction, and first mounting electrodes and second mounting electrodes located on the first upper main surface;

a resin member having a second upper main surface and a second lower main surface arranged in the vertical direction, the second lower main surface being in contact with the first upper main surface;

a cover member having a third upper main surface and a third lower main surface arranged in the vertical direction, and provided with a first through hole and a second through hole penetrating the cover member in the vertical direction, wherein the third lower main surface is in contact with the second upper main surface;

a first connection conductor penetrating the resin member in a vertical direction, a lower end of the first connection conductor being connected to the first mounting electrode, a portion of the first connection conductor being located in the first through hole; and

a second connection conductor penetrating the resin member in the vertical direction, wherein a lower end of the second connection conductor is connected to the second mounting electrode, a part of the second connection conductor is positioned in the second through hole,

in the first through hole, at least a part of the periphery of the first connection conductor is present with the resin member when seen downward,

in the second through hole, at least a part of the periphery of the second connection conductor is present with the resin member when seen downward,

the cover member has a linear expansion coefficient smaller than that of the resin member.

2. The circuit substrate of claim 1, wherein,

the cover member has a higher thermal conductivity than the resin member.

3. The circuit substrate according to claim 1 or 2, wherein,

the material of the cover member is carbon fiber reinforced plastic.

4. The circuit board according to any one of claim 1 to 3, wherein,

the circuit board further includes a second electronic component mounted on the first upper main surface.

5. The circuit substrate according to any one of claims 1 to 4, wherein,

a third through hole penetrating the cover member in the up-down direction,

the resin member is provided in the third through hole.

6. A circuit module is provided with:

the circuit substrate according to any one of claims 1 to 5; and

a first electronic component including a component main body, and a first external electrode and a second external electrode provided on a surface of the component main body,

the first external electrode is connected to the upper end of the first connection conductor,

the second external electrode is connected to an upper end of the second connection conductor.

7. The circuit module of claim 6, wherein,

the cover member has an electrical conductivity such that,

the resin member is present in the first through hole so as to surround the periphery of the first connection conductor when seen downward.

8. The circuit module of claim 7, wherein,

when seen downwards, the first external electrode is accommodated in the outer edge of the first through hole,

the second external electrode is received in an outer edge of the second through hole when seen downward.