Wiring structure and electronic module

Abstract

The wiring structure has a first wiring substrate, a second wiring substrate, and a first connection member that connects the first wiring substrate and the second wiring substrate. The first wiring substrate has a first member, a second member, and a first conductor portion. The second wiring substrate has a first insulating layer and a second conductor portion. The first insulating layer has a first surface and a second surface. The first member has a first top surface and a first side surface. The second member has a second top surface. The first conductor portion has a first conductor on the first top surface and a second conductor on the second top surface. The second conductor portion has a first connection conductor located on the second surface and a second connection conductor located on the first surface. At least a portion of the second surface faces the first top surface and is located at a position overlapping the first top surface in plan view. The first conductor and the first connection conductor are joined, and the first connection member electrically connects the second conductor and the second connection conductor.

Description

Technical Field

[0001] This disclosure relates to wiring structures and electronic modules. Background Technology

[0002] Conventional wiring structures are described, for example, in Patent Document 1.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-5636 Summary of the Invention

[0006] means for solving problems

[0007] In one embodiment, the wiring structure of this disclosure (1) includes a first wiring substrate, a second wiring substrate, and a first connecting member electrically connecting the first wiring substrate and the second wiring substrate. The first wiring substrate has a first member, a first conductor portion, and a second member connected to the first member. The second wiring substrate has a first insulating layer and a second conductor portion. The second wiring substrate extends from the second member. The first insulating layer has a first surface and a second surface opposite to the first surface. The first member has a first top surface and a first side surface intersecting the first top surface. The second member has a second top surface and is opposite to or disposed on a surface of the first member different from the first side surface. The first conductor portion has a first conductor located on the first top surface and a second conductor located on the second top surface. The second conductor portion has a first connecting conductor located on the second surface and a second connecting conductor located on the first surface. At least a portion of the second surface is opposite to the first top surface and is located at a position overlapping the first top surface when viewed from above. The first conductor and the first connecting conductor are joined. The first connecting member electrically connects the second conductor and the second connecting conductor.

[0008] (2) In the wiring structure described in (1) above, the first conductor and the first connecting conductor are grounding conductors.

[0009] (3) In the wiring structure described in (1) or (2) above, the second conductor and the second connecting conductor are signal conductors or grounding conductors.

[0010] (4) The wiring structure described in (1) or (2) above further includes a second connecting member that electrically connects the first wiring substrate and the second wiring substrate. The first conductor portion also includes a third conductor disposed on the second top surface at a distance from the second conductor. The second conductor portion also includes a third connecting conductor disposed on the first surface at a distance from the second connecting conductor. The second connecting member electrically connects the third conductor and the third connecting conductor. The first conductor and the first connecting conductor are grounding conductors. The second conductor and the second connecting conductor are grounding conductors. The third conductor and the third connecting conductor are signal conductors.

[0011] (5) In the wiring structure described in (1) to (4) above, the first connecting conductor and the second connecting conductor are electrically connected in the second wiring substrate.

[0012] (6) In the wiring structure described in (1) to (5) above, the second member has a second side surface that intersects with the first top surface and the second top surface. Furthermore, the first top surface is lower than the second top surface.

[0013] (7) In the wiring structure described in (6) above, in a cross-sectional view orthogonal to the first top surface, the distance L1 from the first top surface to the second top surface is greater than or equal to the distance L2 from the first top surface to the first surface.

[0014] (8) In the wiring structure described in (6) or (7) above, the second wiring substrate is connected to the second side surface.

[0015] (9) In the wiring structure described in (1) to (8) above, the second member has a second side surface that intersects with the first top surface and the second top surface. The second side surface has a first notch and a first conductor layer disposed in the first notch. The surface of the second wiring substrate opposite to the second side surface has a second notch and a second conductor layer disposed in the second notch. The first conductor layer and the second conductor layer are joined together using a bonding material.

[0016] (10) In the wiring structure described in (1) to (9) above, the second member has a second side surface that intersects with the first top surface and the second top surface. The first top surface is lower than the second top surface. The first conductor portion has a side conductor that connects the first conductor and the second conductor. The side conductor is located on the second side surface.

[0017] (11) In the wiring structure described in (1) to (10) above, the first connecting member is a lead wire.

[0018] (12) In the wiring structure described in (11) above, the first connecting member is covered with insulating material.

[0019] (13) In the wiring structure described in (1) to (12) above, the second wiring substrate is a flexible wiring substrate.

[0020] (14) The wiring structure described in (1) to (13) above also has a third wiring substrate that is electrically connected to the second wiring substrate.

[0021] (15) The wiring structure described in (1) to (14) above also has a housing for accommodating electronic components. The first wiring substrate is part of the housing. At least a portion of the first component and the second component is exposed outside the housing.

[0022] In one embodiment, (16) the electronic module has: the wiring structure described in (1) to (14) above; and electronic components electrically connected to the first conductor portion.

[0023] In one embodiment, (17) the electronic module has: the wiring structure described in (15) above; electronic components housed in a housing; and a cover disposed on the housing. Attached Figure Description

[0024] Figure 1 This is a perspective view of the wiring structure and electronic module involved in one embodiment.

[0025] Figure 2 This is a perspective view of a first wiring substrate representing a wiring structure according to one embodiment.

[0026] Figure 3 This is a perspective view of the wiring structure involved in one embodiment, viewed from below.

[0027] Figure 4 yes Figure 1 An enlarged view of the main part IV of the wiring structure shown.

[0028] Figure 5 It is Figure 4 The diagram shows the wiring structure after it has been cut along VV.

[0029] Figure 6 It is Figure 4 The diagram shows the wiring structure after it has been cut along VI-VI.

[0030] Figure 7 This is a cross-sectional view showing an example of a wiring structure having a fourth wiring substrate.

[0031] Figure 8 This is a perspective view showing an example of a wiring structure having a fourth wiring substrate.

[0032] Figure 9 This is a cross-sectional view showing an example of a wiring structure having a fourth wiring substrate.

[0033] Figure 10 This is an enlarged view showing the first notch, the first conductor layer, the second notch, and the second conductor layer.

[0034] Figure 11 This is a graph showing the reflection characteristics of a wiring structure according to one embodiment and the reflection characteristics of a wiring structure according to a comparative example.

[0035] Figure 12 This is a graph showing the throughput characteristics of a wiring structure according to one embodiment and the throughput characteristics of a wiring structure according to a comparative example. Detailed Implementation

[0036] <Structure of the wiring structure>

[0037] Hereinafter, several exemplary embodiments will be described with reference to the accompanying drawings. It should be noted that the wiring structure can be set to either upward or downward, but for convenience, an orthogonal coordinate system xyz is defined, and the positive side of the z-direction is set to upward. Furthermore, in this disclosure, "top view" includes the concept of top perspective.

[0038] like Figures 1-6 As shown, the wiring structure has a first wiring substrate 1, a second wiring substrate 2, and a first connecting member 41 that electrically connects the first wiring substrate 1 and the second wiring substrate 2.

[0039] The first wiring board 1 has a first component 11, a first conductor portion 10, and a second component 12 connected to the first component 11.

[0040] The first component 11 has a first top surface 11u and a first side surface 11s intersecting the first top surface 11u. Alternatively, the first component 11 may also have a first bottom surface 11b opposite to the first top surface 11u. The material of the first component 11 is an insulating material, such as an alumina sintered body, a mullite sintered body, a silicon carbide sintered body, an aluminum nitride sintered body, a silicon nitride sintered body, or a glass-ceramic material.

[0041] The material of the first component 11 can also be a resin material. As a resin material, one selected from epoxy resin, phenolic resin, unsaturated polyester resin, polytetrafluoroethylene resin, urea-formaldehyde resin, melamine resin, thermosetting polyimide resin, etc., can be used. The material of the first component 11 can also be a metallic material. Examples of metallic materials include copper, iron, tungsten, molybdenum, nickel, or cobalt, or alloys containing these metallic materials.

[0042] The second member 12 has a second top surface 12u, and is opposite to or disposed on the surface of the first member 11, which is different from the first side surface 11s. Figure 2In the illustrated embodiment, the second member 12 is located in the x-direction on the side of the first member 11 opposite to the first side surface 11s. However, as a variation, the second member 12 may also be opposite to or disposed on the side surface of the first member 11 in the y-direction. Additionally, the second member 12 may also have a second bottom surface 12b opposite to the second top surface 12u. The material of the second member 12 may be the same as or different from that of the first member 11. When the materials of the first member 11 and the second member 12 are the same, the first member 11 may also be integrally formed with the second member 12. In particular, when the material of the second member 12 is ceramic, it is easy to locate wiring inside the second member 12.

[0043] When the materials of the first component 11 and the second component 12 are different, the first component 11 and the second component 12 can also be bonded by a conductive adhesive material (e.g., silver epoxy resin). In this case, the wiring formed on the second component 12 and the first conductor 111 (described later) formed on the first component 11 can also be electrically connected using a conductive adhesive. Furthermore, in this case, the first component 11 and the second component 12 do not need to be connected without gaps; a partial gap may exist between the first component 11 and the second component 12.

[0044] The wiring may be located in the inner layer of the first component 11 and / or the second component 12.

[0045] The first conductor portion 10 has a first conductor 111 located on a first top surface 11u of the first member 11 and a second conductor 122 located on a second top surface 12u of the second member 12. Examples of materials for the first conductor portion 10 include metallic materials such as gold, silver, copper, nickel, tungsten, molybdenum, and manganese. Alternatively, the first conductor portion 10 can be formed by sintering metal paste onto the first member 11 and / or the second member 12, or it can be formed using thin film formation techniques such as vapor deposition or sputtering. The first conductor portion 10 may also have a plating layer on its surface. Furthermore, if the first member 11 is made of a metallic material, the first conductor 111, described later, may be formed solely by plating.

[0046] like Figure 2 As shown, in one embodiment, the first conductor 111 is configured to cover the entire first top surface 11u, but this is not mandatory; for example, a portion may be interrupted, and there may be multiple first conductors 111. Additionally, in Figure 2 In this description, it is assumed that the first conductor 111 is a grounding conductor. However, there may also be a plurality of first conductors 111 on the first top surface 11u, and they may serve as signal conductors and / or grounding conductors, having the same shape as the second conductor 122 and / or the third conductor 123 located on the second top surface 12u.

[0047] The second wiring substrate 2 has a first insulating layer 21 and a second conductor portion 20. The second wiring substrate 2 extends from the second member 12. The second wiring substrate 2 can be flexible, for example, it can be a so-called flexible printed circuit board (FPC) or a printed circuit board (PCB) on which electronic circuits are formed. When the second wiring substrate 2 is a flexible wiring substrate, its processing becomes easier, and the design freedom is increased. When the second wiring substrate 2 is a flexible wiring substrate, the material of the first insulating layer 21 is a resin material.

[0048] Furthermore, the second wiring substrate 2 can be further bonded to the first side 11s using an insulating adhesive. This reduces the possibility of the second wiring substrate 2 shifting or detaching from the first wiring substrate 1.

[0049] Alternatively, the insulating film may be located on a portion of the second conductor portion 20 of the second wiring substrate 2. More specifically, the insulating film may also be located on the second conductor portion 20, except for the portion where the second wiring substrate 2 overlaps with the first wiring substrate 1 in plan view and / or the portion where the second wiring substrate 2 overlaps with the third wiring substrate 3 (described later) in plan view. This structure reduces the possibility of damage or corrosion to the second conductor portion 20. An example of an insulating film is a cover film.

[0050] The first insulating layer 21 of the second wiring substrate 2 has a first surface 21u and a second surface 21b opposite to the first surface 21u. At least a portion of the second surface 21b faces the first top surface 11u of the first wiring substrate 1 and is located at a position overlapping the first top surface 11u when viewed from above. In other words, the second wiring substrate 2 overlaps with the first wiring substrate 1 at least partially. The material of the first insulating layer 21 may be, for example, resin. In addition, the dielectric constant of the first insulating layer 21 may be lower than the dielectric constant of the first member 11 and / or the dielectric constant of the second member 12.

[0051] like Figure 1 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the second conductor portion 20 of the second wiring substrate 2 has a first connecting conductor 211 located on the second surface 21b and a second connecting conductor 212 located on the first surface 21u. For example, a metallic material can be used as the material for the second conductor portion 20. The second conductor portion 20 can be connected to or separated from the end face of the first insulating layer 21.

[0052] like Figure 5As shown, the first conductor 111 of the first wiring substrate 1 and the first connecting conductor 211 of the second wiring substrate 2 are joined together. The joining of the first conductor 111 and the first connecting conductor 211 can also be performed using a joining material 21J such as solder or conductive resin.

[0053] The first connecting member 41 electrically connects the second conductor 122 of the first wiring substrate 1 to the second connecting conductor 212 of the second wiring substrate 2. With this configuration, compared to electrically connecting the first wiring substrate 1 and the second wiring substrate 2 without using the first connecting member 41, the first conductor portion 10 and the second conductor portion 20 can be designed more precisely in the wiring structure. Therefore, the number of first conductor portions 10 and second conductor portions 20, which serve as electrodes, can be increased, enabling high-density and high-integration wiring. Furthermore, when the second conductor 122 and the second connecting conductor 212 are used as signal conductors, a wiring structure suitable for high-frequency signal transmission can be established.

[0054] like Figure 5 and Figure 6 As shown, in one embodiment, the first conductor 111 and the first connecting conductor 211 can be grounding conductors. According to this structure, the area of ​​the grounding conductor can be increased, thereby strengthening the grounding potential.

[0055] The second conductor 122 and the second connecting conductor 212 can also be signal conductors or grounding conductors. When the first conductor 111 and the first connecting conductor 211 are grounding conductors, the second conductor 122 and the second connecting conductor 212 can also be signal conductors. According to this structure, the first conductor portion 10 and the second conductor portion 20 can be made coplanar, which can stabilize the signal transmission in the second conductor 122 and the second connecting conductor 212. Figures 1-6 In the embodiment shown, the second conductor 122 and the second connecting conductor 212 are described as grounding conductors.

[0056] The first connecting conductor 211 of the second wiring substrate 2 can also cover more than 70% of the area of ​​the second surface 21b. With this structure, the area of ​​the first connecting conductor 211, which serves as a grounding conductor, can be increased, thereby strengthening the grounding potential in the second wiring substrate 2.

[0057] like Figure 4As shown, in one embodiment, the wiring structure may further include a second connecting member 42 that electrically connects the first wiring substrate 1 and the second wiring substrate 2. The first conductor portion 10 may also include a third conductor 123 disposed on the second top surface 12u of the second member 12, spaced apart from the second conductor 122. The second conductor portion 20 may also include a third connecting conductor 213 disposed on the first surface 21u, spaced apart from the second connecting conductor 212. The second connecting member 42 electrically connects the third conductor 123 and the third connecting conductor 213. Alternatively, the first conductor 111 and the first connecting conductor 211 may be grounding conductors, and the second conductor 122 and the second connecting conductor 212 may be grounding conductors, while the third conductor 123 and the third connecting conductor 213 may be signal conductors. As described above, since the first conductor portion 10 can be designed precisely, the dimensions of the third conductor 123 and the third connecting conductor 213 in the y-direction can be reduced in particular. Therefore, with the above structure, the impedance adjustment in the third conductor 123 and the third connecting conductor 213 can be easily performed. Therefore, a wiring structure suitable for high-frequency signal transmission can be designed. Furthermore, the number of third conductors 123 and third connecting conductors 213 can be increased, allowing for the formation of more signal channels within the wiring structure.

[0058] like Figure 2 and Figure 4 As shown, the dimension of the third conductor 123 in the y-direction can also be a shape that increases as it approaches the second side 12s. That is, the width of the third conductor 123 can also be a shape that widens as it approaches the second side 12s. According to this structure, the second connecting member 42 can be stably connected. In addition, a plurality of second connecting members 42 can be connected. Similarly, the dimension of the third conductor portion 30 in the y-direction can also be a shape that increases as it approaches the end face of the second wiring substrate 2 opposite to the second side 12s.

[0059] In order to adjust the impedance according to the frequency of the signal flowing through the conductor, the width of each conductor in the first conductor section 10 and the second conductor section 20 (the dimension in the y direction as shown in the figure) can be adjusted and designed to be larger or smaller.

[0060] Viewed from above, the second conductor 122 can be connected to or disconnected from the second side 12s. Similarly, the third conductor 123 can be connected to or disconnected from the second side 12s when viewed from above. If the third conductor 123 is connected to the second side 12s when viewed from above, the second connecting member 42 can be shortened, thereby reducing the possibility of impedance variation between the third conductor 123 (which serves as a signal conductor) and the third connecting conductor 213.

[0061] The second connecting conductor 212, when viewed from above, can be connected to or disconnected from the end face of the second wiring substrate 2 on the side of the second member 12. Similarly, the third connecting conductor 213, when viewed from above, can be connected to or disconnected from the end face of the second wiring substrate 2 on the side of the second member 12. If the third connecting conductor 213 is connected to the end face of the second wiring substrate 2 on the side of the second member 12 when viewed from above, the second connecting member 42 can be shortened, thereby reducing the possibility of impedance variation between the third conductor 123 (which serves as a signal conductor) and the third connecting conductor 213. Furthermore, if the third connecting conductor 213 is separated from the end face of the second wiring substrate 2 on the side of the second member 12 when viewed from above, even if the bonding material 21J that bonds the first conductor 111 and the first connecting conductor 211 rises from the second surface 21b side to the first surface 21u side, the possibility of a short circuit due to connection between the first connecting conductor 211 and the third connecting conductor 213 can be reduced.

[0062] When there are multiple third conductors 123, a pair of third conductors 123 can function as a differential signal line for transmitting differential signals. In this case, the pair of third conductors 123 can also be located between multiple second conductors 122 that serve as grounding conductors. When the pair of third conductors 123 is a differential signal line, there are also multiple third connecting conductors 213, and a pair of third connecting conductors 213 can also function as a differential signal line for transmitting differential signals.

[0063] And, as Figure 4 As shown, the first conductor portion 10 may also have a fourth conductor 124. The fourth conductor 124 may also be connected to the second conductor portion 20 without utilizing the first connecting member 41 and / or the second connecting member 42. Alternatively, the fourth conductor 124 may be located between a pair of third conductors 123 that serve as signal conductors. With this structure, the ground potential in the first conductor portion 10 can be strengthened. Therefore, the possibility of resonance in the pair of third conductors 123 can be reduced. The fourth conductor 124 may be connected to or separated from the second side surface 12s when viewed from above. When the first conductor portion 10 has a fourth conductor 124, the second wiring board 2 may also have a conductor electrically connected to the fourth conductor 124.

[0064] In addition, such as Figure 2 and Figure 6As shown, the first top surface 11u may also have a first conductor 111 serving as a grounding conductor and a first exposed area 110 exposed on the first top surface 11u. The first exposed area 110 only needs to be located at least in plan view at a position overlapping with the position where the first connecting member 41 and / or the second connecting member 42 is connected to the second conductor portion 20 of the second wiring substrate 2. According to this structure, the first conductor 111 can be moved away from below the connection position of the first connecting member 41 and / or the second connecting member 42 with the second conductor portion 20. Therefore, at the connection position of the first connecting member 41 and / or the second connecting member 42 with the second conductor portion 20, the possibility of an increase in capacitance can be reduced.

[0065] Furthermore, the first exposed area 110 can be connected to or separated from the second side 12s. Figure 2 In the illustrated embodiment, the first conductor 111 has a first exposed area 110 between the portion connected to the side conductor 114. However, as a variation, the shape of the first exposed area 110 may also be a strip extending in the y-direction. The position, size, and shape of the first exposed area 110 may be appropriately determined based on the connection position between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20.

[0066] like Figure 3 and Figure 6 As shown, the second surface 21b of the second wiring substrate 2 may have a first connecting conductor 211 serving as a grounding conductor and a second exposed area 210 exposed on the second surface 21b. The second exposed area 210 only needs to be located at least in plan view at a position overlapping with the connection point between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20 of the second wiring substrate 2. According to this structure, the first connecting conductor 211 can be positioned away from the connection point between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20. Therefore, at the connection point between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20, the possibility of increased capacitance can be reduced.

[0067] Furthermore, the second exposed area 210 can be connected to or separated from the end face of the second wiring substrate 2. Figure 3 In the illustrated embodiment, the first connecting conductor 211 has a partially interrupted second exposed region 210. However, as a variation, the shape of the second exposed region 210 may also be a strip extending in the y-direction along the end face of the first insulating layer 21. The position, size, and shape of the second exposed region 210 may be appropriately determined based on the connection position between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20.

[0068] Viewed from above, the first exposed area 110 and the second exposed area 210 may at least partially overlap. With this structure, compared to the case where the first exposed area 110 and the second exposed area 210 do not overlap, the first connecting conductor 211 can be positioned further below the connection point between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20. Therefore, at the connection point between the first connecting member 41 and / or the second connecting member 42 and the second conductor portion 20, the possibility of an increase in capacitance can be more effectively reduced.

[0069] like Figure 1 , Figure 2 and Figure 4 As shown, the second member 12 may also have a recess 120 located at least on the second top surface 12u. The recess 120 may, for example, be located between a plurality of third conductors 123 and / or between the second conductor 122 and the third conductor 123. The recess 120 is filled with at least one dielectric material such as air, resin, or glass, with a dielectric constant lower than that of the second member 12. Therefore, the capacitance component can be reduced between the second conductor 122 and the third conductor 123 and / or between a plurality of third conductors 123. Therefore, the characteristic impedance in the third conductor 123 can be adjusted to a desired value when transmitting high-frequency signals. Therefore, the signal power loss generated in the first conductor portion 10 can be reduced.

[0070] The first connecting conductor 211 and the second connecting conductor 212 can also be electrically connected within the second wiring substrate 2. More specifically, such as Figure 5 As shown, the first connecting conductor 211 and the second connecting conductor 212 can also be connected via the through-hole conductor 21V. For example, when the first connecting conductor 211 and the second connecting conductor 212 are grounding conductors, the ground potential can be strengthened. When the first connecting conductor 211 and the second connecting conductor 212 are signal conductors, the signals flowing through the first connecting conductor 211 and the second connecting conductor 212 can be combined, and the signal can be amplified. When the first connecting conductor 211 and the second connecting conductor 212 are power supply conductors, a larger drive current can flow through them.

[0071] Here, as Figure 5As shown, the via conductor 21V connecting the first connecting conductor 211 and the second connecting conductor 212 can also be a so-called blind via. That is, the via conductor 21V connecting the first connecting conductor 211 and the second connecting conductor 212 may not be a via. If this structure is used, the possibility of the bonding material 21J flowing out towards the first surface 21u and short-circuiting with the third connecting conductor 213 can be reduced. In addition, the first connecting member 41 is bonded to the surface of the second connecting conductor 212, but when the first connecting member 41 is bonded to the second connecting conductor 212, the possibility of the flatness of the surface of the second connecting conductor 212 being reduced due to the bonding material 21J can be reduced. Furthermore, in the second wiring substrate 2, it is not necessary for all via conductors 21V to be blind vias; for example, blind vias may only be present at the locations where the second wiring substrate 2 overlaps with the first wiring substrate 1.

[0072] The first top surface 11u and the second top surface 12u can also be coplanar. According to this structure, the height (dimension in the z-direction) of the first wiring substrate 1 can be reduced. When the heights of the first top surface 11u and the second top surface 12u are different, the first top surface 11u and the second top surface 12u may not be completely parallel. For example, the first top surface 11u may be inclined in the positive x-axis direction, or it may be inclined in the positive or negative x-axis direction, or in the positive or negative y-axis direction.

[0073] like Figure 2 and Figure 6 As shown, the second member 12 may also have a second side surface 12s that intersects the first top surface 11u and the second top surface 12u. Furthermore, the first top surface 11u may be lower than the second top surface 12u. According to this structure, when the second wiring substrate 2 is located on the first top surface 11u, since the heights of the first conductor portion 10 and the second conductor portion 20 can be made close, the lengths of the first connecting member 41 and / or the second connecting member 42 can be shortened as much as possible. Therefore, in the electrical connection portion between the first wiring substrate 1 and the second wiring substrate 2, the possibility of impedance value variation can be reduced. Additionally, when the second wiring substrate 2 is located on the first top surface 11u, the positioning of the second wiring substrate 2 can be easily performed.

[0074] The second wiring substrate 2 can also be connected to the second side surface 12s. This makes it easier to position the second wiring substrate 2 when it is positioned on the first top surface 11u. Furthermore, it reduces the possibility of the second wiring substrate 2 deviating from its intended position on the first top surface 11u. Alternatively, the second wiring substrate 2 may not be connected to the second side surface 12s. In this case, the possibility of the second wiring substrate 2 being damaged due to contact with the second side surface 12s is reduced.

[0075] like Figure 6 As shown, in a cross-sectional view orthogonal to the first top surface 11u, the distance L1 from the first top surface 11u to the second top surface 12u can also be greater than or equal to the distance L2 from the first top surface 11u of the first wiring substrate 1 to the first surface 21u of the second wiring substrate 2. When the distance L1 from the first top surface 11u to the second top surface 12u and the distance L2 from the first top surface 11u of the first wiring substrate 1 to the first surface 21u of the second wiring substrate 2 are equal, the length of the second connecting member 42 can be shortened as much as possible by adjusting the thickness of the third conductor 123 and the third connecting conductor 213. Therefore, the possibility of impedance variation in the electrical connection portion of the first wiring substrate 1 and the second wiring substrate 2 can be reduced.

[0076] When the second member 12 has a second side surface 12s that intersects with the first top surface 11u and the second top surface 12u, and the first top surface 11u is lower than the second top surface 12u, such as Figure 2 As shown, the first conductor portion 10 may also have a side conductor 114 connecting the first conductor 111 and the second conductor 122. The side conductor 114 is located on the second side 12s. According to this structure, when the first conductor 111 and the second conductor 122 are grounding conductors, the grounding potential can be strengthened.

[0077] In addition, such as Figure 2 As shown, the dimension of the side conductor 114 in the y direction can also be smaller than the dimension of the second conductor 122 in the y direction.

[0078] Furthermore, when the first component 11 and the second component 12 are integral, the first conductor 111 may also extend into the interior of the second conductor 122. In this case, the first conductor 111 and the second conductor 122 may also be electrically connected via a through-hole formed in the second component 12.

[0079] The first connecting member 41 can be a lead wire or a strip lead wire. The first connecting member 41 connecting the second conductor 122 and the second connecting conductor 212 is not limited to one type, such as... Figure 4 As shown, there can be two or more. The second connecting member 42 can be a lead wire or a strip lead wire, such as... Figure 4 As shown, there can be a plurality of second connecting members 42. The electrical connection state between the first wiring substrate 1 and the second wiring substrate 2 and the first connecting member 41 and / or the second connecting member 42 in one embodiment can be referred to as wire bonding or tape bonding.

[0080] like Figure 4As shown, the first connecting member 41, which connects the two second conductors 122 sandwiched between a pair of third conductors 123 and the two second connecting conductors 212 sandwiched between a pair of third connecting conductors 213, can be spaced wider toward the second wiring substrate 2 (i.e., the positive direction of the x-axis as shown in the figure).

[0081] When a pair of third conductors 123 and a pair of third connecting conductors 213 are respectively connected by second connecting members 42, the spacing of each second connecting member 42 can increase as it moves toward the second wiring substrate 2 (i.e., the positive direction of the x-axis as shown in the figures). When transmitting signals between the pair of third conductors 123 and the pair of third connecting conductors 213, the possibility of abrupt impedance changes can be reduced, and the possibility of unwanted electrical signals being reflected back to the pair of third conductors 123 and the pair of third connecting conductors 213 can be reduced.

[0082] The first connecting member 41 may also be covered with an insulating material. Additionally, the second connecting member 42 may also be covered with an insulating material. According to this configuration, since the first connecting member 41 and / or the second connecting member 42 can be protected from external impacts, the possibility of the electrical connection between the first wiring substrate 1 and the second wiring substrate 2 being interrupted due to the first connecting member 41 and / or the second connecting member 42 detaching can be reduced.

[0083] like Figure 1 As shown, the wiring structure may also have a third wiring substrate 3 electrically connected to the second wiring substrate 2. The third wiring substrate 3 may also be a printed circuit board on which electronic circuits are formed. More specifically, it is sufficient that the third conductor portion 30 located on the third wiring substrate 3 is electrically connected to the second conductor portion 20 of the second wiring substrate 2.

[0084] Additionally, at the location where the second wiring substrate 2 overlaps with the third wiring substrate 3, the second wiring substrate 2 may also have a fourth connecting conductor 214 located on the second surface 21b. The fourth connecting conductor 214 may be electrically connected to the third connecting conductor 213, or both the fourth and third connecting conductors 213 may be signal conductors.

[0085] The third connecting conductor 213 and the fourth connecting conductor 214 can also be electrically connected through a through-hole located in the second wiring substrate 2. In this case, the connection between the third connecting conductor 213 and the fourth connecting conductor 214 does not have to be a blind hole.

[0086] The electrical connection between the second wiring substrate 2 and the third wiring substrate 3 is not only the joining of the fourth connecting conductor 214 and the third conductor portion 30, but can also be the same as the electrical connection between the second wiring substrate 2 and the first wiring substrate 1, including lead-based connections. Furthermore, the connecting components such as leads connecting the second wiring substrate 2 and the third wiring substrate 3 can also be covered with insulating material.

[0087] like Figure 1 As shown, the wiring structure may also have a housing 5 for accommodating electronic components 6. In this case, the first wiring substrate 1 may also be part of the housing 5, and at least a portion of the first component 11 and the second component 12 may be exposed outside the housing 5.

[0088] The enclosure 5 may also have a plate 51 located at least on the second bottom surface 12b of the second member 12, and a frame 52 joined to the plate 51 and / or the first wiring substrate 1. The electronic component 6, which will be described later, can be accommodated within the space formed by the plate 51, the frame 52, and the first wiring substrate 1.

[0089] Examples of materials for the plate 51 include metals such as copper, iron, tungsten, molybdenum, nickel, or cobalt, or alloys containing these metals. In this case, the plate 51 can also be a single metal plate or a stack of multiple metal plates. Furthermore, when the metal material constituting the plate 51 is one of the aforementioned metals, to reduce oxidation corrosion, a plating layer of nickel or gold can be formed on the surface of the plate 51 using electroplating or electroless plating. Moreover, the plate 51 described here as being made of a metallic material is acceptable as long as it is substantially made of a metallic material; for example, the plate 51 may also contain non-metallic materials that are unavoidable in manufacturing. Additionally, a high-heat-dissipation component using carbon materials such as graphite can also be used as the material for the plate 51.

[0090] The frame 52 may be made of the same material as or different from the material of the plate 51 and / or the second member 12. The frame 52 may also have a light-transmitting portion 520 that extends through the inside and outside of the housing 5. The light-transmitting portion 520 functions as a window for transmitting and receiving light inside and outside the housing 5.

[0091] Furthermore, the first wiring substrate 1 may also have a third component 13 located on the second component 12. The second component 12 and the third component 13 may also be integral and made of an insulating material. In this case, the materials of the second component 12 and the third component 13 may be ceramic materials.

[0092] <Variation Example>

[0093] The first member 11 has a first bottom surface 11b on the side opposite to the first top surface 11u. The second member 12 has a second bottom surface 12b on the side opposite to the second top surface 12u. Furthermore, in... Figure 3In the illustrated embodiment, the first bottom surface 11b and the second bottom surface 12b are coplanar; however, for example, the second bottom surface 12b may protrude further in the negative z-axis direction than the first bottom surface 11b. The conductor may also be located on the first bottom surface 11b and the second bottom surface 12b in the same manner as the first conductor portion 10 formed on the first top surface 11u and the second top surface 12u. In this case, a fourth wiring substrate 70, different from the second wiring substrate 2 described above, may be mounted on the conductor formed on the first bottom surface 11b and the second bottom surface 12b. In this case, the electrical connection between the first wiring substrate 1 and the fourth wiring substrate 70 may also include a connection based on a third connecting member 72. The third connecting member may be, for example, a lead wire.

[0094] The fourth wiring substrate 70 may be flexible, for example, it may be a so-called flexible wiring substrate (FPC) or a printed circuit board (PCB) on which electronic circuits are formed.

[0095] like Figure 7 As shown, a fourth wiring substrate 70 can also be added and connected to the first bottom surface 11b of the first member 11. According to this structure, the wiring structure can exchange more electrical signals. In this case, the electrical connection between the first wiring substrate 1 and the fourth wiring substrate 70 can also include a connection based on the third connecting member 72.

[0096] like Figure 8 and Figure 9 As shown, the first wiring substrate 1 may also have a protrusion 16 that protrudes from the first side 11s in the positive direction of the x-axis. A fourth wiring substrate 70 may also be attached to this protrusion 16.

[0097] like Figure 9 As shown, the protrusion 16 can also be stepped. Additionally, as... Figure 9 As shown, when the fourth wiring substrate 70 is located on the protrusion 16, the fourth wiring substrate 70 can also be electrically connected to the conductor located on the protrusion 16 via the third connecting member 72.

[0098] like Figures 7-9 As shown, the second wiring substrate 2 and the fourth wiring substrate 70 can also be bonded to each other via the first side 11s using an insulating adhesive 71 such as resin. This improves the bonding strength between the first wiring substrate 1, the second wiring substrate 2, and the fourth wiring substrate 70. Figure 9 As shown, adhesive 71 can also cover the third joint member.

[0099] Furthermore, when the first top surface 11u is located lower than the second top surface 12u, the first wiring substrate 1 can also have a plurality of structures that serve as the first top surface 11u and the second top surface 12u. That is, as... Figure 2As shown, in the first wiring substrate 1, a step is formed from the first top surface 11u to the second top surface 12u, but there may be multiple steps.

[0100] In addition, the second wiring substrate 2, such as Figure 7 As shown, it can also be bonded to the first side surface 11s of the first wiring substrate 1, or it can be bonded to the first bottom surface 11b of the first wiring substrate 1 by allowing the adhesive to reach from the first side surface 11s to the first bottom surface 11b. In this case, the second wiring substrate 2 can also be bonded to the first bottom surface 11b using an insulating adhesive 71 such as resin.

[0101] like Figure 10 As shown, notches can also be provided on the second side 12s of the second member 12 in the first wiring substrate 1 and on the surface of the second wiring substrate 2 opposite to the second side 12s. Conductor layers are provided on the sides of the notches, and the conductor layers are joined together using a bonding material such as solder. That is, when the second side 12s has a first notch 14 and a first conductor layer 15 provided in the first notch 14, and the surface of the second wiring substrate 2 opposite to the second side 12s has a second notch 24 and a second conductor layer 25 provided in the second notch 24, the first conductor layer 15 and the second conductor layer 25 can also be joined together using a bonding material.

[0102] The first notch 14 and the first conductor layer 15 can, for example, form a castellation structure, and the second notch 24 and the second conductor layer 25 can also, for example, form a castellation structure.

[0103] At this time, if the first conductor layer 15 provided in the first notch 14 is connected to the conductor of the first conductor portion 10 of the first wiring substrate 1 (at least one of the first conductor 111 and the second conductor 122), and the second conductor layer 25 provided in the second notch 24 is connected to the connecting conductor of the second conductor portion 20 of the second wiring substrate 2 (at least one of the first connecting conductor 211 and the second connecting conductor 212), then the conductor of the first conductor portion 10 and the connecting conductor of the second conductor portion 20 can be securely electrically connected. For example, if both the conductor of the first conductor portion 10 connected to the first conductor layer 15 and the connecting conductor of the second conductor portion 20 connected to the second conductor layer 25 are grounded conductors, then by connecting them via the first conductor layer 15 and the second conductor layer 25, the grounding potential can be made secure.

[0104] Furthermore, the number of first notches 14 on the second side 12s and the number of second notches 24 on the side of the second wiring substrate 2 opposite to the second side 12s can be the same or any number greater than 1.

[0105] Figure 10 The diagram shows an example where the first conductor layer 15 is connected to the second conductor 122, and the second conductor layer 25 is connected to the second connecting conductor 212; the first connecting member 41 is omitted. The connection between the conductor of the first conductor portion 10 of the first wiring substrate 1 and the first conductor layer 15, and the connection between the connecting conductor of the second conductor portion 20 of the second wiring substrate 2 and the second conductor layer 25, are not limited to... Figure 10 The example shown. As described above, the first conductor layer 15 can be connected to the first conductor 111, and the second conductor layer 25 can be connected to the first connecting conductor 211.

[0106] <Simulation Results>

[0107] Figure 11 It means Figures 1-6 The graph showing the reflection characteristics of the wiring structure has the horizontal axis representing the frequency of the input signal (GHz) and the vertical axis representing the reflection characteristic (dB). Furthermore, in the graph representing reflection characteristics, a smaller reflection characteristic (dB) value means less signal reflection. Solid lines represent the characteristics of a wiring structure according to one embodiment of this disclosure. On the other hand, dashed lines represent the characteristics of a wiring structure according to a comparative example. In the wiring structure of the comparative example, the first member 11 and the first connecting member 41 are removed from the wiring structure of this disclosure, and the second wiring substrate 2 is bonded to the second conductor 122 and the third conductor 123. (Refer to...) Figure 11 It can be seen that the wiring structure disclosed herein has better reflection characteristics compared with the comparative example.

[0108] Figure 12 It means Figures 1-6 The graph showing the throughput characteristics of the wiring structure uses the horizontal axis to represent the frequency of the input signal (GHz) and the vertical axis to represent the throughput characteristic (dB). Furthermore, in the graph representing throughput characteristics, a higher throughput characteristic (dB) value indicates less signal loss. Solid lines represent the characteristics of a wiring structure according to one embodiment of this disclosure. On the other hand, dashed lines represent the characteristics of a wiring structure according to a comparative example. (See also...) Figure 12 It can be seen that the wiring structure disclosed herein has better throughput characteristics compared with the comparative example.

[0109] <Structure of Electronic Module>

[0110] In one embodiment, the electronic module may also have a wiring structure and an electronic component 6 electrically connected to the first conductor portion 10. The electronic component 6 may not necessarily be covered by the cover described later.

[0111] In one embodiment, the electronic module may also have a wiring structure, an electronic component 6 housed in the housing 5, and a cover disposed on the housing 5.

[0112] The cover is configured to cover the inside of the housing 5 and, together with the housing 5, protect the electronic components 6.

[0113] Examples of electronic components 6 include optical semiconductor elements such as laser diodes (LDs) or photodiodes (PDs), semiconductor integrated circuit elements such as field-effect transistors (FETs), and sensor elements such as optical sensors. Electronic component 6 can be formed from semiconductor materials such as gallium arsenide or gallium nitride. The electronic module may have multiple electronic components 6, not just one, and of multiple types. In this case, electronic component 6 may also be, for example, an amplifier or a capacitor.

[0114] The electronic module may also have a sealing ring located between the cover and the frame 52. The sealing ring has the function of engaging the cover and the frame 52.

[0115] In one embodiment, the electronic module can be used as a transceiver for optical communication.

[0116] Furthermore, the various combinations of embodiments and modifications are not limited to the examples of the embodiments described above. In addition, combinations of embodiments and / or modifications with each other are also possible.

[0117] Industrial availability

[0118] This disclosure can be used in wiring structures and electronic modules.

[0119] Explanation of reference numerals in the attached figures

[0120] 1 First wiring substrate

[0121] 10 First Conductor Section

[0122] 11 First Component

[0123] 11u First Top Surface

[0124] 11b First base

[0125] 11s First side view

[0126] 110 First exposed area

[0127] 111 First Conductor

[0128] 114 Side Conductor

[0129] 12 Second component

[0130] 12u Second Top Surface

[0131] 12b Second bottom surface

[0132] 12s Second side

[0133] 120 recess

[0134] 122 Second Conductor

[0135] 123 Third Conductor

[0136] 124 Fourth Conductor

[0137] 13 Third component

[0138] 14 First Gap

[0139] 15 First Conductor Layer

[0140] 16. Protrusions

[0141] 2 Second wiring substrate

[0142] 20 Second conductor section

[0143] 21 First Insulation Layer

[0144] 21u First Page

[0145] 21b Second page

[0146] 210 Second exposed area

[0147] 211 First connecting conductor

[0148] 212 Second connecting conductor

[0149] 213 Third connecting conductor

[0150] 214 Fourth connecting conductor

[0151] 21V through-hole conductor

[0152] 21J bonding material

[0153] 24 Second notch

[0154] 25 Second conductor layer

[0155] 3 Third wiring board

[0156] 30 Third Conductor Section

[0157] 41 First connecting member

[0158] 42 Second connecting member

[0159] 5 enclosures

[0160] 51 plate body

[0161] 52 Frame

[0162] 520 Light-transmitting section

[0163] 6 Electronic components

[0164] 70 Fourth Wiring Board

[0165] 71 Adhesive

[0166] 72 Third connecting member.

Claims

1. A wiring structure, wherein, have: A first wiring board has a first component, a first conductor portion, and a second component connected to the first component; The second wiring substrate has a first insulating layer and a second conductor portion; as well as The first connecting member electrically connects the first wiring substrate and the second wiring substrate. The second wiring substrate extends from the second component. The first insulating layer has a first surface and a second surface opposite to the first surface. The first component has a first top surface and a first side surface intersecting the first top surface. The second component has a second top surface, and is opposite to or disposed on a surface of the first component that is different from the first side surface. The first conductor portion has a first conductor located on the first top surface and a second conductor located on the second top surface. The second conductor portion has a first connecting conductor located on the second surface and a second connecting conductor located on the first surface. At least a portion of the second surface faces the first top surface and, when viewed from above, is located at a position overlapping the first top surface. The first conductor and the first connecting conductor are joined together. The first connecting member electrically connects the second conductor to the second connecting conductor.

2. The wiring structure according to claim 1, wherein, The first conductor and the first connecting conductor are grounding conductors.

3. The wiring structure according to claim 1 or 2, wherein, The second conductor and the second connecting conductor are signal conductors or grounding conductors.

4. The wiring structure according to any one of claims 1 to 3, wherein, The wiring structure also has a second connecting member that electrically connects the first wiring substrate and the second wiring substrate. The first conductor portion further includes a third conductor disposed on the second top surface at a distance from the second conductor. The second conductor portion further includes a third connecting conductor disposed on the first surface at a distance from the second connecting conductor. The second connecting member electrically connects the third conductor to the third connecting conductor. The first conductor and the first connecting conductor are grounding conductors. The second conductor and the second connecting conductor are grounding conductors. The third conductor and the third connecting conductor are signal conductors.

5. The wiring structure according to any one of claims 1 to 4, wherein, The first connecting conductor and the second connecting conductor are electrically connected within the second wiring substrate.

6. The wiring structure according to any one of claims 1 to 5, wherein, The second component has a second side surface that intersects the first top surface and the second top surface. The first top surface is lower than the second top surface.

7. The wiring structure according to claim 6, wherein, In a cross-sectional view orthogonal to the first top surface, the distance L1 from the first top surface to the second top surface is greater than or equal to the distance L2 from the first top surface to the first surface.

8. The wiring structure according to claim 6 or 7, wherein, The second wiring substrate is connected to the second side surface.

9. The wiring structure according to any one of claims 1 to 8, wherein, The second component has a second side surface that intersects the first top surface and the second top surface. The second side has a first notch and a first conductor layer disposed in the first notch. The second wiring substrate has a second notch on the side opposite to the second side and a second conductor layer disposed in the second notch. The first conductor layer and the second conductor layer are joined using a bonding material.

10. The wiring structure according to any one of claims 1 to 9, wherein, The second component has a second side surface that intersects the first top surface and the second top surface. The first top surface is lower than the second top surface. The first conductor portion has a side conductor that electrically connects the first conductor and the second conductor. The side conductor is located on the second side.

11. The wiring structure according to any one of claims 1 to 10, wherein, The first connecting component is a lead wire.

12. The wiring structure according to claim 11, wherein, The first connecting member is covered with insulating material.

13. The wiring structure according to any one of claims 1 to 12, wherein, The second wiring substrate is a flexible wiring substrate.

14. The wiring structure according to any one of claims 1 to 13, wherein, The wiring structure also has a third wiring substrate that is electrically connected to the second wiring substrate.

15. The wiring structure according to any one of claims 1 to 14, wherein, The wiring structure also has a housing to accommodate electronic components. The first wiring board is part of the housing. At least a portion of the first component and the second component are exposed outside the housing.

16. An electronic module, wherein, have: The wiring structure according to any one of claims 1 to 14; and An electronic component is electrically connected to the first conductor portion.

17. An electronic module, wherein, have: The wiring structure as described in claim 15; Electronic components, housed within the enclosure; and A cover is provided on the box body.

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