Electronic module, method for manufacturing an electronic module, and electronic device.

Abstract

To reduce a noise in an intermediate connection member.SOLUTION: An electronic module comprises: a first wiring board; a second wiring board that is arranged so as to be separated from the first wiring board in a first direction; and an intermediate connection member that is arranged between the first wiring board and the second wiring board. The intermediate connection member includes: an insulation body; a plurality of first wirings that are supported by the insulation body, and are arranged in a second direction crossing to the first direction with an interval; a plurality of second wirings that are supported by the insulation body, and are arranged in the second direction with an interval; and a metal layer that is supported by the insulation body, and is arranged between the plurality of first wirings and the plurality of second wirings so as to be opposite to the plurality of first wirings and the plurality of second wirings in a third direction crossing the first direction and the second direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a technique for laminating a first wiring board and a second wiring board.

Background Art

[0002] An electronic device including an electronic module having a plurality of wiring boards is known. Due to the demand for miniaturization of electronic devices, high-density mounting has been required in electronic modules. As one of the structures for realizing high-density mounting, a three-dimensional mounting structure configured by stacking a plurality of wiring boards in multiple stages is known. In the three-dimensional mounting structure, there are methods of connecting two opposing wiring boards to each other using solder balls, and methods of connecting two opposing wiring boards to each other using an intermediate connecting member having wirings. Patent Document 1 discloses a three-dimensional mounting structure configured by connecting two mounting substrates with an intermediate connecting member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, due to the demand for further miniaturization of electronic devices, further miniaturization has been required in electronic modules, that is, intermediate connecting members. Due to the miniaturization of the intermediate connecting member, the distance between wirings in the intermediate connecting member becomes narrow, so it is required to reduce the noise generated by the wirings in the intermediate connecting member.

[0005] Therefore, an object of the present invention is to reduce noise in an intermediate connecting member.

Means for Solving the Problems

[0006] According to a first aspect of the present invention, an electronic module comprises a first wiring board, a second wiring board spaced apart from the first wiring board in a first direction, and an intermediate connecting member disposed between the first wiring board and the second wiring board, wherein the intermediate connecting member comprises an insulator, a plurality of first wirings supported by the insulator and spaced apart from each other in a second direction intersecting the first direction, a plurality of second wirings supported by the insulator and spaced apart from each other in the second direction, and the insulator Caught in between It has a metal layer that is supported and positioned between the plurality of first wirings and the plurality of second wirings so as to face the plurality of first wirings and the plurality of second wirings in a third direction intersecting the first direction and the second direction, The plurality of first wirings include a first ground wiring and a first signal wiring, the first ground wiring being joined to a first ground pad of the first wiring board by a conductive first bonding member, and the first signal wiring being joined to a first signal pad of the first wiring board by a conductive second bonding member, sandwiched between the insulators. The aforementioned metal Layers , extending from one end to the other end of the insulator in the first direction, The first ground pad to The aforementioned Joined by the first joining member Ori , The first joining member is a continuous solder, including a portion joined to the first ground wiring and a portion of the metal layer sandwiched between the insulators that is joined to the first ground pad. It is characterized by the following: According to a second aspect of the present invention, the electronic module comprises a first wiring board, a second wiring board spaced apart from the first wiring board in a first direction, and an intermediate connecting member disposed between the first wiring board and the second wiring board, wherein the intermediate connecting member has an insulator, a plurality of first wirings supported by the insulator and spaced apart from each other in a second direction intersecting the first direction, a plurality of second wirings supported by the insulator and spaced apart from each other in a second direction, and a metal layer supported by the insulator and disposed between the plurality of first wirings and the plurality of second wirings so as to face the plurality of first wirings and the plurality of second wirings in a third direction intersecting the first and second directions, wherein the plurality of first wirings and the plurality of second wirings include signal wiring used for signal transmission. The plurality of first wirings and the plurality of second wirings are spaced apart from both ends of the insulator in the second direction. The distance between the signal wiring and the metal layer is characterized in that it is less than or equal to the distance between the two closest wirings among the plurality of first wirings and the plurality of second wirings. [Effects of the Invention]

[0008] According to the present invention, noise can be reduced in the intermediate connecting member. [Brief explanation of the drawing]

[0009] [Figure 1] This is an explanatory diagram of a digital camera, which is an imaging device as an example of an electronic device according to the first embodiment. [Figure 2] (a) is a plan view of an imaging module, which is an example of an electronic module according to the first embodiment. (b) is a cross-sectional view of the imaging module according to the first embodiment. [Figure 3] (a) is a perspective view of the intermediate connecting member according to the first embodiment. (b) is a cross-sectional view of the intermediate connecting member according to the first embodiment. [Figure 4] (a) to (c) are enlarged cross-sectional views of the connection structure between the wiring board and the intermediate connecting member according to the first embodiment. [Figure 5] (a) to (c) are enlarged cross-sectional views of the connection structure between the wiring board and the intermediate connecting member according to the first embodiment. [Figure 6] (a) to (d) are explanatory diagrams of the manufacturing method of the imaging module according to the first embodiment. [Figure 7] (a) to (c) are explanatory diagrams illustrating the manufacturing method of the imaging module according to the first embodiment. [Figure 8] (a) is a perspective view of the intermediate connecting member according to the second embodiment. (b) is an enlarged perspective view of a part of the intermediate connecting member according to the second embodiment. [Figure 9] (a) and (b) are enlarged cross-sectional views of the connection structure between the wiring board and the intermediate connecting member according to the third embodiment. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

[0011] [First Embodiment] FIG. 1 is an explanatory diagram of a digital camera 600 which is an example of an electronic device according to the first embodiment. The digital camera 600 is an interchangeable-lens digital camera and includes a camera body 601. A lens unit 602 including a lens is detachable from the camera body 601. The lens unit 602 is an interchangeable lens, that is, a lens barrel.

[0012] The camera body 601 includes a housing 611, and an imaging module 200 and an image processing module 400 disposed inside the housing 611. The imaging module 200 and the image processing module 400 are electrically connected to each other communicably via a flexible printed wiring board 950. A signal indicating image data generated in the imaging module 200 is transmitted to the image processing module 400 via the flexible printed wiring board 950. The signal indicating image data is a digital signal.

[0013] The imaging module 200 is an example of an electronic module and has a three-dimensional mounting structure. The imaging module 200 includes circuit units 201 and 202, and a plurality of intermediate connection members 300 which are an example of at least one intermediate connection member. The circuit unit 201 is an example of a first circuit unit, and the circuit unit 202 is an example of a second circuit unit.

[0014] The image processing module 400 includes a printed wiring board 401 and an image processing device 402 which is a semiconductor element mounted on the printed wiring board 401. The image processing device 402 is, for example, a digital signal processor. The image processing device 402 is configured to perform image processing on the image data acquired from the imaging module 200.

[0015] FIG. 2(a) is a plan view of the imaging module 200, and FIG. 2(b) is a cross-sectional view of the imaging module 200. In FIG. 2(a), for the sake of explanation, illustration of the circuit unit 202 is omitted. FIG. 2(b) is a cross-sectional view of the imaging module 200 along the line IIB-IIB shown in FIG. 2(a).

[0016] The circuit unit 201 is a printed wiring board, a printed circuit board, or a semiconductor package, and in the first embodiment, it is, for example, a printed circuit board. The circuit unit 202 is a printed wiring board, a printed circuit board, or a semiconductor package, and in the first embodiment, it is, for example, a semiconductor package.

[0017] The circuit unit 201 and the circuit unit 202 are arranged at intervals so as to face each other in the Z direction, which is the stacking direction. Between the circuit unit 201 and the circuit unit 202, a plurality of intermediate connection members 300 are arranged as an example of at least one intermediate connection member.

[0018] Each intermediate connection member 300 is arranged between the circuit unit 201 and the circuit unit 202 and is used to electrically and mechanically connect the circuit unit 201 and the circuit unit 202.

[0019] The circuit unit 202 includes a wiring board 221 including two main surfaces 2211 and 2212, and an image sensor 222 arranged on the main surface 2211 of the wiring board 221. The main surface 2212 is the main surface facing the wiring board 211. The main surface 2211 is the main surface on the back side with respect to the main surface 2212. The wiring board 221 is an example of a second wiring board and is a package substrate. Also, the wiring board 221 is a rigid printed wiring board. The image sensor 222 is an example of a second semiconductor element and is, for example, a semiconductor chip. Further, the circuit unit 202 has a frame 223 arranged on the main surface 2211 of the wiring board 221 so as to surround the image sensor 222, and a LID 224 arranged on the frame 223 so as to face the image sensor 222 at an interval. For the LID 224, a substrate made of, for example, glass is used.

[0020] The wiring board 221 has a flat insulating substrate 220. The material of the insulating substrate 220 is preferably a resin with a low coefficient of thermal expansion. The main surfaces 2211 and 2212 of the wiring board 221 are also the main surfaces of the insulating substrate 220.

[0021] The image sensor 222 is, for example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor. The image sensor 222 has the function of converting light incident via the lens unit 602 into an electrical signal and generating image data based on the electrical signal. The image sensor 222 is preferably sized to accommodate larger formats such as APSC size or full-frame, as image resolution increases.

[0022] The circuit unit 201 includes a wiring board 211 with two main surfaces 2111 and 2112, a memory 212 disposed on the main surface 2111 of the wiring board 211, and an electronic component 213 disposed on the main surface 2111 of the wiring board 211. The memory 212 is an example of a first semiconductor element. The main surface 2111 is the main surface facing the wiring board 221. The main surface 2112 is the main surface on the back side of the main surface 2111. The wiring board 211 is an example of a first wiring board and is a rigid printed circuit board. The memory 212 is, for example, a semiconductor chip and, in the first embodiment, can store image data. The electronic component 213 is a chip component smaller in size than the memory 212 and is, for example, a passive element such as a resistor, capacitor, or inductor, or an active element such as a semiconductor component. Thus, at least one electronic component 213 and a relatively large memory 212 are mounted on the main surface 2111 of the wiring board 211 as mounted components.

[0023] The wiring board 211 has a flat insulating substrate 210. The insulating substrate 210 is preferably made of a resin such as an epoxy resin containing glass fibers. The main surfaces 2111 and 2112 of the wiring board 211 are also the main surfaces of the insulating substrate 210.

[0024] In the first embodiment, the main surface 2111 of the wiring board 211 is positioned opposite the main surface 2212 of the wiring board 221 in the Z direction. Therefore, the memory 212 and the electronic component 213 are positioned between the wiring board 211 and the wiring board 221 in the Z direction. The multiple intermediate connecting members 300 are positioned between the wiring board 211 and the wiring board 221 to maintain the distance between them so that the memory 212 and the electronic component 213 do not interfere with the wiring board 221. In other words, the multiple intermediate connecting members 300 also serve as spacers.

[0025] Multiple intermediate connecting members 300 are arranged to surround the memory 212 and the electronic component 213. In the first embodiment, there are four intermediate connecting members 300. Each intermediate connecting member 300 is configured to electrically connect the signal lines, power lines, and ground lines of the wiring board 211 to the signal lines, power lines, and ground lines of the wiring board 221.

[0026] The wiring board 221 has a plurality of pads 225 positioned in a location corresponding to the intermediate connecting member 300. The plurality of pads 225 are provided on the main surface 2212. Each pad 225 is made of a conductive material, such as a metal such as copper. Each pad 225 is, for example, a signal pad, a power pad, a ground pad, or a dummy pad. Each intermediate connecting member 300 is joined to the corresponding pad 225 among the plurality of pads 225 by a conductive joining member 352 such as solder. If the joining member 352 that joins the intermediate connecting member 300 and the wiring board 221 is solder, then the intermediate connecting member 300 can be said to be soldered to the wiring board 221.

[0027] A solder resist film (not shown) may be provided on the main surface 2212. In this case, it is preferable that openings are formed in the solder resist film at positions corresponding to each pad 225. The shape of each pad 225 is not particularly limited and may be circular or polygonal in plan view, for example. Furthermore, the relationship between the solder resist film and the pads may be either SMD (Solder Mask Defined) or NSMD (Non-Solder Mask Defined).

[0028] The wiring board 211 has a plurality of pads 215 positioned corresponding to the intermediate connecting member 300, a plurality of pads 216 positioned corresponding to the memory 212, and a plurality of pads 217 positioned corresponding to the electronic component 213. These pads 215, 216, and 217 are provided on the main surface 2111. Each pad 215, 216, and 217 is made of a conductive material, such as a metal such as copper. Each pad 215, 216, and 217 is, for example, a signal pad, a power pad, a ground pad, or a dummy pad. Each intermediate connecting member 300 is joined to the corresponding pad 215 among the plurality of pads 215 with a conductive joining member 351 such as solder. When the joining member 351 that joins the intermediate connecting member 300 and the wiring board 211 is solder, the intermediate connecting member 300 is connected to the wiring board 2 1 It can be said that it is soldered to 1. The memory 212 is joined to multiple pads 216 with a conductive bonding material such as solder. Each electronic component 213 is joined to the corresponding pad 217 among multiple pads 217 with a conductive bonding material such as solder.

[0029] A solder resist film (not shown) may be provided on the main surface 2111. In this case, it is preferable that openings are formed in the solder resist film at positions corresponding to each pad 215, 216, and 217. The shape of each pad 215, 216, and 217 is not particularly limited and may be circular or polygonal in plan view, for example. Furthermore, the relationship between the solder resist film and the pads may be either SMD or NSMD.

[0030] Multiple intermediate connecting members 300 have similar configurations. The following description will focus on one intermediate connecting member 300. Figure 3(a) is a perspective view of the intermediate connecting member 300 according to the first embodiment. Figure 3(b) is a cross-sectional view of the intermediate connecting member 300.

[0031] The intermediate connecting member 300 is, for example, a rectangular parallelepiped rigid wiring board. Here, the longitudinal direction of the intermediate connecting member 300 is the X direction, and the width direction, i.e., the thickness direction, is the Y direction. The height direction, i.e., the short direction, of the intermediate connecting member 300 is the Z direction. The Z direction is an example of a first direction, the Y direction is an example of a third direction, and the X direction is an example of a second direction. The X, Y, and Z directions intersect each other. In this embodiment, the X, Y, and Z directions are orthogonal to each other. The intermediate connecting member 300 maintains the distance in the Z direction between two opposing main surfaces 2111, 2212, while connecting two circuit units 201, 202, i.e., two wiring boards 211, 2 21 To connect them electrically and mechanically, it is preferable that they be in the shape of a rectangular parallelepiped that is long in the X direction.

[0032] The intermediate connecting member 300 has end faces 300L and 300U spaced apart in the Z direction. End face 300L faces the main surface 2111 of the wiring board 211 in the Z direction. End face 300U faces the main surface 2212 of the wiring board 221 in the Z direction.

[0033] The intermediate connecting member 300 includes a flat insulating substrate 310, which is an example of an insulator; a metal layer 309 disposed inside the insulating substrate 310; and a plurality of wirings 330, for example 16, arranged on the insulating substrate 310 and each extending in the Z direction. Each wiring 330 is supported by the insulating substrate 310. In this way, a large number of wirings 330 are densely arranged on the insulating substrate 310.

[0034] The insulating substrate 310 is preferably made of a resin such as a glass fiber-containing epoxy resin. Considering the need to increase the density of mounted components in the imaging module 200 and to secure mounting area, the thickness of the intermediate connecting member 300 in the Y direction is preferably 5 mm or less, and therefore, the thickness of the insulating substrate 310 in the Y direction is preferably 2 mm or less. The thickness of the metal layer 309 in the Y direction is preferably 0.5 mm or less, taking into account the thickness of the intermediate connecting member 300 in the Y direction, the thickness of the insulating substrate 310 in the Y direction, the thickness of the wiring 330 in the Y direction, and the pitch of the wiring 330 in the X direction.

[0035] Each wire 330 is electrically connected to the respective signal lines, power lines, ground lines, or dummy lines of the wiring boards 211 and 221. Each wire 330 extends from one end to the other of the insulating substrate 310 in the Z direction. The dimension H11 of each wire 330 in the Z direction is greater than the dimension L11 of each wire 330 in the X direction. Of the two end faces 330L and 330U of each wire 330 in the Z direction, end face 330L is included in the end face 300L of the intermediate connecting member 300. End face 330L is joined to the corresponding pad 215 of the multiple pads 215 in Figure 2(b) by the joining member 351. Of the two end faces 330L and 330U of each wire 330 in the Z direction, end face 330U is included in the end face 300U of the intermediate connecting member 300. The end face 330U is joined to the corresponding pad 225 among the multiple pads 225 in Figure 2(b) by the joining member 352. In summary, the pads 215 of the wiring board 211 and the wiring 330 of the intermediate connecting member 300 are electrically and mechanically connected by the joining member 351, and the pads 225 of the wiring board 221 and the wiring 330 of the intermediate connecting member 300 are electrically and mechanically connected by the joining member 352.

[0036] Each joining member 351, 352 is composed of a conductive material, such as solder. The material of joining member 352 is the same as the material of joining member 351. The solder included in joining members 351, 352 is preferably Sn-Ag-Cu or Sn-Bi solder. Although each joining member 351, 352 preferably contains solder, it is not limited to this, and may also contain inorganic materials such as copper, silver, or aluminum, or organic materials such as conductive rubber. Furthermore, each joining member 351, 352 may be, for example, a cured product of an organic conductive adhesive.

[0037] The insulating substrate 310 includes two insulating substrates 311 and 312. Insulating substrate 311 is an example of a first insulating substrate, and insulating substrate 312 is an example of a second insulating substrate. Each insulating substrate 311 and 312 is a flat insulating member. Insulating substrate 312 is spaced apart from insulating substrate 311 in the Y direction. Of the 16 wirings 330, a plurality of wirings, eight wirings 3301 in this embodiment, are arranged on the insulating substrate 311 of the insulating substrate 310. Of the plurality of wirings 330, a plurality of wirings other than wirings 3301, eight wirings 3302 in this embodiment, are arranged on the insulating substrate 312 of the insulating substrate 310. Each wiring 3301 is an example of a first wiring. Each wiring 3302 is an example of a second wiring. The plurality of wirings 3301 are spaced apart from each other in the X direction. The plurality of wirings 3302 are spaced apart from each other in the X direction.

[0038] Each wiring 330 and metal layer 309 is composed of a conductive material, such as an inorganic material like copper, silver, or aluminum, or an organic material like conductive rubber. Each wiring 330 may be formed by pressing metal foil together, or by applying a conductive paste with a dispenser and firing it.

[0039] Multiple wirings 3301 are arranged on one of the two outer surfaces of the insulating substrate 310 that are spaced apart in the Y direction, and multiple wirings 3302 are arranged on the other outer surface of the two outer surfaces. That is, the insulating base material 311 of the insulating substrate 310 is arranged between the multiple wirings 3301 and the metal layer 309, and the insulating base material 312 of the insulating substrate 310 is arranged between the multiple wirings 3302 and the metal layer 309.

[0040] The insulating substrate 311 of the insulating substrate 310 has a surface 3111 facing the insulating substrate 312, and a surface 3112 on the back side of surface 3111. The insulating substrate 312 of the insulating substrate 310 has a surface 3121 facing the insulating substrate 311, and a surface 3122 on the back side of surface 3121. Surfaces 3111 and 3121 face each other. Surfaces 3112 and 3122 are also the outer surfaces of the insulating substrate 310. That is, multiple wirings 3301 are arranged on surface 3112, and multiple wirings 3302 are arranged on surface 3122. The metal layer 309 is arranged between surface 3111 and surface 3121.

[0041] Thus, the metal layer 309 is located between the insulating substrate 311 and the insulating substrate 312, and is positioned between the multiple wirings 3301 and 3302 so as to be sandwiched between them. As a result, the metal layer 309 faces the multiple wirings 3301 and 3302 in the Y direction.

[0042] The metal layer 309 extends from one end to the other of the insulating substrates 311 and 312 in the Z direction. Two end faces 309L and 309U of the metal layer 309 in the Z direction are exposed to the outside. End face 309L is included in end face 300L of the intermediate connecting member 300. End face 309U is included in end face 300U of the intermediate connecting member 300.

[0043] Figures 4(a) to 4(c) are enlarged cross-sectional views of the connection structure between the wiring board 211 and the intermediate connecting member 300 according to the first embodiment. Figures 5(a) to 5(c) are enlarged cross-sectional views of the connection structure between the wiring board 221 and the intermediate connecting member 300 according to the first embodiment. Figures 4(a) to 5(c) show cross-sections of the connection structure at different positions in the X direction.

[0044] The wiring board 211 includes a ground wire 211G, several signal lines 211S1, 211S2, 211S3, and power lines (not shown). The ground wire 211G is an example of a first ground. Each of the signal lines 211S1, 211S2, 211S3 is used for transmitting digital signals. The ground wire 211G includes several ground pads 215G1, 215G2. . Round Pad 215G 1 is the This is an example of a ground pad. Groundpad 215G2 is an example of a second groundpad. Signal line 211S1 includes signal pad 215S1. Signal line 211S2 includes signal pad 215S2. Signal line 211S3 includes signal pad 215S3. Signal pad 215S2 is an example of a first signal pad. Signal pad 215S1 is an example of a second signal pad. Signal pad 215S3 is an example of a third signal pad.

[0045] The wiring board 221 includes a ground wire 221G, several signal lines 221S1, 221S2, 221S3, and power lines (not shown). The ground wire 221G is an example of a second ground. Each of the signal lines 221S1, 221S2, 221S3 is used for the transmission of digital signals. The ground wire 221G includes several ground pads 225G1, 225G2. . Round Pad 225G 1 is the third This is an example of a ground pad. Ground pad 225G2 is an example of a fourth ground pad. Signal line 221S1 includes signal pad 225S1. Signal line 221S2 includes signal pad 225S2. Signal line 221S3 includes signal pad 225S3. Signal pad 225S2 is an example of the fourth signal pad. Signal pad 225S1 is an example of the fifth signal pad. Signal pad 225S3 is an example of the sixth signal pad.

[0046] Each of the multiple wirings 330, namely multiple wirings 3301 and multiple wirings 3302, includes at least one signal wiring, at least one ground wiring, and at least one power wiring. In the examples in Figures 4(a) to 5(c), multiple wiring 3301 includes multiple ground wirings 330G11, 330G21, 330G31, 330G41 and multiple signal wirings 330S11, 330S21. Multiple wiring 3302 includes multiple ground wirings 330G12, 330G22 and multiple signal wirings 330S12, 330S22, 330S32, 330S42. Each signal wiring 330S11, 330S21, 330S12, 330S22, 330S32, 330S42 is used for the transmission of digital signals. . Round wiring 330G11 is the This is an example of ground wiring. Ground wiring 330G2 1 This is an example of a second ground wiring. Ground wiring 330G12 is the third This is an example of ground wiring. . Round wiring 330G31 is the 4th This is an example of ground wiring. Ground wiring 330G4 1 This is an example of wiring to the fifth ground. Ground wiring 330G22 is the 6th This is an example of ground wiring. Signal wiring 330S1 1 This is an example of the first signal wiring. Signal wiring 330S1 2 This is an example of a second signal wiring. Signal wiring 330S2 2 This is an example of a third signal wiring. Signal wiring 330S2 1 This is an example of a fourth signal wiring. Signal wiring 330S3 2 This is an example of a fifth signal wiring. Signal wiring 330S4 2 This is an example of a sixth signal wiring.

[0047] Interference noise such as mutual interference, radiated noise, or conducted noise occurs in the signals transmitted through each signal wiring 330S11 to 330S42. The metal layer 309 has a wider width in the X direction than each signal wiring 330S11 to 330S42. According to the first embodiment, these noises are reduced by the metal layer 309 placed near each signal wiring 330S11 to 330S42, and the quality of the transmitted signal is improved.

[0048] Specifically, since the metal layer 309 is placed between signal wiring 330S11 and signal wiring 330S22, interference noise between signal wiring 330S11 and signal wiring 330S22 can be reduced. Similarly, since the metal layer 309 is placed between signal wiring 330S21 and signal wiring 330S42, interference noise between signal wiring 330S21 and signal wiring 330S42 can be reduced. In addition, interference noise between each signal wiring 330S11 to 330S42 and other adjacent signal wiring or power wiring in the X direction can also be reduced. Furthermore, since the metal layer 309 is placed near each signal wiring 330S11 to 330S42, radiated noise and conducted noise in each signal wiring 330S11 to 330S42 can be reduced.

[0049] If the joining members 351 and 352 contain solder, the metal layer 309 is preferably soldered to at least one of the wiring boards 211 and 221, and in the first embodiment, it is soldered to both wiring boards 211 and 221. In the first embodiment, the metal layer 309 is joined to each ground pad 215G1 and 215G2 with their respective joining members 351G1 and 351G2 so as to be electrically connected to the ground wire 211G. In the first embodiment, the end face 309L of the metal layer 309 is exposed to the outside, so the end face 309L is joined to each ground pad 215G1 and 215G2 with their respective joining members 351G1 and 351G2. As a result, the metal layer 309 is at the same potential as the ground wire 211G. Each ground pad 215G1 and 215G2 faces the end face 309L of the metal layer 309 in the Z direction.

[0050] The ground wiring 330G11 is connected to the ground pad 215G1 by a connecting member 351G1, thereby electrically connecting it to the metal layer 309 and the ground wire 211G, and becoming at the same potential as the metal layer 309 and the ground wire 211G. The ground pad 215G1 faces the end face 330L of the ground wiring 330G11 in the Z direction.

[0051] In the first embodiment, the ground pad 215G1 faces the end face 309L of the metal layer 309 and the end face 330L of the ground wiring 330G11 in the Z direction.

[0052] The ground wiring 330G21 is connected to the ground pad 215G2 by a connecting member 351G2, thereby electrically connecting it to the metal layer 309 and the ground wire 211G, and becoming at the same potential as the metal layer 309 and the ground wire 211G. The ground pad 215G2 faces the end face 330L of the ground wiring 330G21 in the Z direction.

[0053] The ground wiring 330G12 is electrically connected to the metal layer 309, the ground wire 211G, and the ground wiring 330G21 by being joined to the ground pad 215G2 with a connecting member 351G2. Therefore, the ground wiring 330G12 is at the same potential as the metal layer 309, the ground wire 211G, and the ground wiring 330G21. The ground pad 215G2 faces the end face 330L of the ground wiring 330G12 in the Z direction.

[0054] In the first embodiment, the ground pad 215G2 has a larger area than the ground pad 215G1 when viewed in the Z direction. The ground pad 215G2 is facing the end face 300L of the metal layer 309, the end face 330L of the ground wiring 330G21, and the end face 330L of the ground wiring 330G12 in the Z direction.

[0055] Signal wiring 330S12 is electrically connected to signal line 211S1 by being joined to signal pad 215S1 with connecting member 351S1. Similarly, signal wiring 330S11 is electrically connected to signal line 211S2 by being joined to signal pad 215S2 with connecting member 351S2. Furthermore, signal wiring 330S22 is electrically connected to signal line 211S3 by being joined to signal pad 215S3 with connecting member 351S3. Joining member 351G1 is an example of a first joining member. Joining member 351S2 is an example of a second joining member. Joining member 351G2 is an example of a third joining member. Joining member 351S1 is an example of a fourth joining member. Joining member 351S3 is an example of a fifth joining member.

[0056] In the first embodiment, the metal layer 309 is joined to each ground pad 225G1, 225G2 by their respective joining members 352G1, 352G2 so as to be electrically connected to the ground wire 221G. In the first embodiment, the end face 309U of the metal layer 309 is exposed to the outside, so the end face 309U is joined to each ground pad 225G1, 225G2 by their respective joining members 352G1, 352G2. As a result, the metal layer 309 is at the same potential as the ground wire 221G. Each ground pad 225G1, 225G2 faces the end face 309U of the metal layer 309 in the Z direction.

[0057] The ground wiring 330G31 is connected to the ground pad 225G1 by a connecting member 352G1, thereby electrically connecting it to the metal layer 309 and the ground wire 221G, and becoming at the same potential as the metal layer 309 and the ground wire 221G. The ground pad 225G1 faces the end face 330U of the ground wiring 330G31 in the Z direction.

[0058] In the first embodiment, the ground pad 225G1 faces the end face 309U of the metal layer 309 and the end face 330U of the ground wiring 330G31 in the Z direction.

[0059] The ground wiring 330G41 is connected to the ground pad 225G2 by a connecting member 352G2, thereby electrically connecting it to the metal layer 309 and the ground wire 221G, and becoming at the same potential as the metal layer 309 and the ground wire 221G. The ground pad 225G2 faces the end face 330U of the ground wiring 330G41 in the Z direction.

[0060] The ground wiring 330G22 is electrically connected to the metal layer 309, the ground wire 221G, and the ground wiring 330G41 by being joined to the ground pad 225G2 with a connecting member 352G2. Therefore, the ground wiring 330G22 is at the same potential as the metal layer 309, the ground wire 221G, and the ground wiring 330G41. The ground pad 225G2 faces the end face 330U of the ground wiring 330G22 in the Z direction.

[0061] In the first embodiment, the ground pad 225G2 has a larger area than the ground pad 225G1 when viewed in the Z direction. The ground pad 225G2 is located on the end face 30 of the metal layer 309. 9 U, the end face 330U of ground wiring 330G41, and the end face 330U of ground wiring 330G22 are facing each other in the Z direction.

[0062] Signal wiring 330S32 is electrically connected to signal line 221S1 by being joined to signal pad 225S1 with connecting member 352S1. Similarly, signal wiring 330S21 is electrically connected to signal line 221S2 by being joined to signal pad 225S2 with connecting member 352S2. Furthermore, signal wiring 330S42 is electrically connected to signal line 221S3 by being joined to signal pad 225S3 with connecting member 352S3. Joining member 352G1 is an example of the sixth joining member. Joining member 352S2 is an example of the seventh joining member. Joining member 352G2 is an example of the eighth joining member. Joining member 352S1 is an example of the ninth joining member. Joining member 352S3 is an example of the tenth joining member.

[0063] As described above, the metal layer 309 is at ground potential, so noise to the signals transmitted through each signal wiring can be effectively reduced.

[0064] Furthermore, the ground wiring 330G11 shown in Figure 4(a) may be joined to a ground pad (not shown) of the ground wire 221G of the wiring board 221 together with the metal layer 309 using a connecting member, similar to Figure 5(a). Also, the signal wiring 330S12 shown in Figure 4(a) may be joined to a signal pad (not shown) of a signal wire (not shown) of the wiring board 221 using a connecting member, similar to Figure 5(a).

[0065] Furthermore, the ground wires 330G21 and 330G12 shown in Figure 4(b) may be joined together with the metal layer 309 to a ground pad (not shown) of the ground wire 221G of the wiring board 221 using a connecting member, similar to Figure 5(b).

[0066] Furthermore, the signal wiring 330S11 shown in Figure 4(c) may be joined to an unshown signal pad of an unshown signal line on the wiring board 221 using a connecting member, similar to Figure 5(c). Similarly, the signal wiring 330S22 shown in Figure 4(c) may be joined to an unshown signal pad of an unshown signal line on the wiring board 221 using a connecting member, similar to Figure 5(c).

[0067] Furthermore, the ground wiring 330G31 shown in Figure 5(a) may be joined to a ground pad (not shown) of the ground wire 211G of the wiring board 211 together with the metal layer 309 using a connecting member, similar to Figure 4(a). Also, the signal wiring 330S32 shown in Figure 5(a) may be joined to a signal pad (not shown) of a signal line (not shown) of the wiring board 211 using a connecting member, similar to Figure 4(a).

[0068] Furthermore, the ground wires 330G41 and 330G22 shown in Figure 5(b) may be joined together with the metal layer 309 to a ground pad (not shown) of the ground wire 211G of the wiring board 211 using a joining member, similar to Figure 4(b).

[0069] Furthermore, the signal wiring 330S21 shown in Figure 5(c) may be joined to an unshown signal pad of an unshown signal line on the wiring board 211 using a connecting member, similar to Figure 4(c). Similarly, the signal wiring 330S42 shown in Figure 5(c) may be joined to an unshown signal pad of an unshown signal line on the wiring board 211 using a connecting member, similar to Figure 4(c).

[0070] Also, in Figures 4(a) to 5(c), the signal wiring 330S11, 330S21, 330S12, 330S22, 330 S 32,330 SAlternatively, a power supply wire may be used instead of wire 42, and the corresponding pad may be designated as the power supply pad. Alternatively, one of these wires may be connected to a dummy pad.

[0071] The ground wires 330G11, 330G21, 330G31, 330G41, 330G12, and 330G22 included in the intermediate connecting member 300 carry a larger current than the signal wires. Therefore, each ground wire 330G11 to 330G22 is required to have lower resistance. Accordingly, each ground wire 330G11 to 330G22 may be constructed from a conductive material with lower resistance or from a wire with a larger diameter.

[0072] The width in the X direction and thickness in the Y direction of each wiring 330 should be considered according to the application of the wiring and the application of the connected electronic component 320, but it is preferable that they be 0.01 mm or more and 2 mm or less. When considering high density of multiple wirings 330, it is more preferable that the width in the X direction and thickness in the Y direction of each wiring 330 be 0.5 mm or less. The width (thickness) in the Y direction of the metal layer 309 is preferably wider than the distance D2 in the X direction between two adjacent wirings 3301 among the multiple wirings 3301.

[0073] The length of the intermediate connecting member 300 in the X direction is preferably shorter than the length of one side of each wiring board 211, 221. The width of the intermediate connecting member 300 in the Y direction is preferably as thin as possible, as this increases the mounting area on the wiring board 211 where components can be mounted. The height of the intermediate connecting member 300 in the Z direction is preferably greater than the tallest mounted component, such as the memory 212. For example, if a mounted component with a height of 1.6 mm is mounted on the wiring board 211, the height of the intermediate connecting member 300 in the Z direction is preferably 1.6 mm or more. The number and pitch of the wiring 330 of the intermediate connecting member 300 depend on the number of pads on the wiring boards 211, 221 and the pitch between the pads. The pitch of multiple wirings 3301 and the pitch of multiple wirings 3302 may be set to be the same or to be set to be different.

[0074] In the first embodiment, the distance D0 in the Y direction between one of the multiple signal wires 330S11 to 330S42, for example, signal wire 330S12, and the metal layer 309 is preferably less than or equal to the distance D1 between the two closest wires among the multiple wires 3301 and 3302. In the first embodiment, the two closest wires among the multiple wires 3301 and 3302 are one wire 3301 and one wire 3302 that are adjacent to each other in the Y direction, with the metal layer 309 in between. In the first embodiment, the distance D0 is also preferably less than or equal to the distance D2 between two adjacent wires 3301 in the X direction. By arranging each signal wire 330S11 to 330S42 close to the metal layer 309 in this way, noise to the signal can be reduced more effectively.

[0075] The metal layer 309 is preferably a solid metal member, but is not limited thereto. For example, the metal layer 309 may be a mesh-like metal member, or a metal member in which multiple metal plates spaced apart in the X direction are connected by wiring. The metal layer 309 is preferably a continuous metal member.

[0076] Next, the manufacturing method of the imaging module 200 will be described. Figures 6(a) to 7(c) are explanatory diagrams of each step in the manufacturing method of the imaging module 200.

[0077] In the process shown in Figure 6(a), a wiring board 211 is prepared. The wiring board 211 has a plurality of pads 215, a plurality of pads 216, and a plurality of pads 217.

[0078] Next, in the process shown in Figure 6(b), conductive paste PA is placed on each pad 215-217. The conductive paste PA is preferably a conductive adhesive such as solder paste or silver paste. Alternatively, the conductive paste PA may be a sheet-type conductive adhesive. The conductive paste PA is preferably a solder paste containing solder powder and flux. The conductive paste PA can be supplied, for example, by screen printing or a dispenser. The conductive paste PA may be supplied so as to cover the entire exposed portion of each pad 215-217, or it may be supplied so as to cover only a portion of the exposed portion of each pad 215-217, as in offset printing.

[0079] In the process shown in Figure 6(c), the wiring board 211 is positioned in a predetermined location with each pad 215-217 on the wiring board 211 facing vertically upward. Then, the memory 212, electronic components 213, and intermediate connecting members 300 are placed on the main surface 2111 of the wiring board 211. Specifically, the memory 212 is placed on pad 216 in contact with the conductive paste PA, and the electronic components 213 are placed on pad 217 in contact with the conductive paste PA. The intermediate connecting members 300 are placed on pad 215 by bringing each wiring 330 into contact with the corresponding conductive paste PA. These memory 212, electronic components 213, and intermediate connecting members 300 are then mounted onto the wiring board 211 using a mounter (not shown).

[0080] Next, the conductive paste PA is heated to a temperature above the melting point of the metal powder contained in the conductive paste PA, such as solder powder. This causes the solder powder to melt and the molten solder to agglomerate. Subsequently, the molten solder is cooled and solidified. As a result, the memory 212, electronic component 213, and intermediate connecting member 300 are joined to the wiring board 211, as shown in Figure 6(d). Note that the heating step of heating and melting the conductive paste PA, and the cooling step of cooling and solidifying the molten metal, as shown in Figure 6(d), can be performed, for example, in a reflow oven. The intermediate connecting member 300 is joined to the corresponding pad 215 with the corresponding joining member 351.

[0081] Next, in the process shown in Figure 7(a), conductive paste PB is placed on each pad 225 of the wiring board 221. The conductive paste PB is preferably a conductive adhesive such as solder paste or silver paste. Alternatively, the conductive paste PB may be a sheet-type conductive adhesive. The conductive paste PB is preferably a solder paste containing solder powder and flux, and is preferably made of the same material as the conductive paste PA described above. The conductive paste PB can be supplied, for example, by screen printing or a dispenser. The conductive paste PB may be supplied so as to cover the entire exposed portion of each pad 225, or it may be supplied so as to cover only a portion of the exposed portion of each pad 225, as in offset printing.

[0082] Then, with each pad 225 on the wiring board 221 facing downward in the vertical direction, the wiring board 221 is placed on the end face 300U of the intermediate connecting member 300. That is, the conductive paste PB on the pads 225 is brought into contact with the end face 330U (Figure 3(a)) of the corresponding wiring 330. The circuit unit 202 is placed on the intermediate connecting member 300 using a mounter (not shown).

[0083] Next, the conductive paste PB is heated to a temperature above the melting point of the metal powder contained in it, such as solder powder. This causes the solder powder to melt and the molten solder to agglomerate. Subsequently, the molten solder is cooled, causing it to solidify. As a result, the intermediate connecting member 300 and the wiring board 221 are joined by the corresponding joining member 352, as shown in Figure 7(b). The heating and cooling steps of the conductive paste PB can be performed, for example, in a reflow oven.

[0084] Next, in the process shown in Figure 7(c), the image sensor 222, frame 223, and LID 224 are mounted on the wiring board 221 to fabricate the circuit unit 202. This completes the fabrication of the imaging module 200. Note that pads (not shown) are pre-formed on the wiring board 221 for bonding the image sensor 222 with a wire such as gold.

[0085] The imaging module 200 can be manufactured through the process described above. This enables high-density mounting of the imaging module 200. Furthermore, it becomes possible to manufacture a miniaturized imaging module 200 with high precision.

[0086] [Second Embodiment] Next, an intermediate connecting member according to the second embodiment will be described. Figure 8(a) is a perspective view of the intermediate connecting member 300A according to the second embodiment. Figure 8(b) is an enlarged perspective view of a part of the intermediate connecting member 300A. The electronic module of the second embodiment is the imaging module 200 of the first embodiment, in which the intermediate connecting member 300 shown in Figure 2(a), etc., is replaced with the intermediate connecting member 300A. In the second embodiment, the same reference numerals are used for components similar to those in the first embodiment, and their description is omitted.

[0087] The intermediate connecting member 300A is, for example, a rectangular parallelepiped rigid wiring board. The longitudinal direction of the intermediate connecting member 300A is the X direction, and the width direction, i.e., the thickness direction, is the Y direction. The height direction, i.e., the short direction, of the intermediate connecting member 300A is the Z direction. The Z direction is an example of a first direction, the Y direction is an example of a third direction, and the X direction is an example of a second direction. The X, Y, and Z directions intersect each other. In this embodiment, the X, Y, and Z directions are orthogonal to each other.

[0088] The intermediate connecting member 300A includes an insulating substrate 310A, which is an example of an insulator, a metal layer 309A, and a plurality of wirings 330A, each extending in the Z direction. Each wiring 330A is supported by the insulating substrate 310A. The insulating substrate 310A includes an insulating substrate 311A, which is an example of a first insulating substrate, an insulating substrate 312A, which is an example of a second insulating substrate, and an insulating layer 313A disposed between the insulating substrate 311A ​​and the insulating substrate 312A. The metal layer 309A is disposed inside the insulating substrate 310A, and in the second embodiment, between the insulating substrate 311A ​​and the insulating substrate 312A. The plurality of wirings 330A are disposed between the insulating substrate 311A ​​and the insulating substrate 312A. The plurality of wirings 330A are arranged in a staggered pattern with the metal layer 309A in between. The multiple wirings 330A include multiple wirings 330A1 arranged on an insulating substrate 311A ​​and multiple wirings 330A2 arranged on an insulating substrate 312A. Each wiring 330A1 is an example of a first wiring. Each wiring 330A2 is an example of a second wiring. The material of each insulating substrate 311A, 312A is preferably a resin such as a glass fiber-containing epoxy resin.

[0089] Each wiring 330A is electrically connected to the respective signal line, power line, or ground line of the wiring boards 211 and 221 in Figure 2(b). Each insulating substrate 311A ​​and 312A is a flat insulating member. The insulating substrate 312A is spaced apart from the insulating substrate 311A ​​in the Y direction. Multiple wirings 330A1 are spaced apart from each other in the X direction. Multiple wirings 330A2 are spaced apart from each other in the X direction.

[0090] Each wiring 330A and metal layer 309A is composed of a conductive material, such as an inorganic material like copper, silver, or aluminum, or an organic material like conductive rubber. Each wiring 330A may be formed by pressing metal foil together, or by applying a conductive paste with a dispenser and firing it.

[0091] Multiple wirings 330A1 are arranged between the insulating substrate 311A ​​and the metal layer 309A, and multiple wirings 330A2 are arranged between the insulating substrate 312A and the metal layer 309A. The insulating substrate 311A ​​has a surface 3111A facing the insulating substrate 312A. The insulating substrate 312A has a surface 3121A facing the insulating substrate 311A. That is, surfaces 3111A and 3121A face each other. Multiple grooves are formed on surface 3111A for which multiple wirings 330A1 are arranged. Multiple grooves are formed on surface 3121A for which multiple wirings 330A2 are arranged. The metal layer 309A is arranged between surface 3111A and surface 3121A via the insulating layer 313A. The insulating layer 313A is a cured product such as an adhesive and is made of a different material from the insulating substrates 311A ​​and 312A.

[0092] Thus, the metal layer 309A is located between the insulating substrate 311A ​​and the insulating substrate 312A, and is positioned between the multiple wirings 330A1 and 330A2 so as to be sandwiched between them. As a result, the metal layer 309A faces the multiple wirings 330A1 and 330A2 in the Y direction.

[0093] The metal layer 309A extends from one end to the other of the insulating substrates 311A ​​and 312A in the Z direction. The two end faces 309LA and 309UA of the metal layer 309A in the Z direction are exposed to the outside.

[0094] Multiple wirings 330A1 and multiple wirings 330A2 include at least one signal wiring 330SA. In the example in Figure 8(a), the signal wiring 330SA is included in multiple wirings 330A2. Because the signal wiring 330SA is located near the metal layer 309A, noise is reduced in the signal transmitted through the signal wiring 330SA, improving the quality of the transmitted signal.

[0095] In the second embodiment, each wire 330A is, for example, a wire with a diameter of 0.2 mm. The pitch of the multiple wires 330A is, for example, 0.4 mm. The thickness of the metal layer 309A is, for example, 0.02 mm. The thickness of the insulating layer 313A is, for example, 0.02 mm.

[0096] The distance D10 in the Y direction between the signal wiring 330SA and the metal layer 309A is preferably less than or equal to the distance D11 between the two closest wirings among the multiple wirings 330A1 and multiple wirings 330A2. In the second embodiment, the two closest wirings among the multiple wirings 330A1 and multiple wirings 330A2 are one wiring 330A1 and one wiring 330A2 that are adjacent to each other across the metal layer 309A. This wiring 330A2 is, for example, the signal wiring 330SA. In the second embodiment, the distance D10 is also preferably less than or equal to the distance D12 between two adjacent wirings 330A1 in the X direction. By arranging the signal wiring 330SA close to the metal layer 309A in this way, noise to the signal can be reduced more effectively.

[0097] The metal layer 309A is preferably a solid metal member, but is not limited thereto. For example, the metal layer 309A may be a mesh-like metal member, or a metal member in which multiple metal plates spaced apart in the X direction are connected by wiring. The metal layer 309A is preferably a continuous metal member.

[0098] The imaging module, including the intermediate connecting member 300A, is free from solder joint defects and can fully guarantee the optical performance of the image sensor 222. Furthermore, in the intermediate connecting member 300A, the metal layer 309A, which is positioned between multiple wires 330A, reduces noise in the transmitted signal and improves the quality of the transmitted signal.

[0099] [Third Embodiment] Next, an intermediate connecting member according to the third embodiment will be described. Figures 9(a) and 9(b) are enlarged cross-sectional views of the connection structure between the wiring board 221 and the intermediate connecting member 300B according to the third embodiment. Figures 9(a) and 9(b) show cross-sections of the connection structure at different positions in the X direction. In the third embodiment, components similar to those in the first embodiment are described by using the same reference numerals.

[0100] In the first embodiment described above, the case in which the metal layer 309 is joined to the ground pad together with the ground wiring was explained, but the embodiment is not limited to this. In the third embodiment, the connection structure shown in Figures 5(a) and 5(b) described in the first embodiment is changed to the connection structure shown in Figures 9(a) and 9(b). The intermediate connecting member 300B of the third embodiment has an insulating substrate 310 including insulating substrates 311 and 312, a metal layer 309, and signal wiring 330S32, similar to the first embodiment. Although not shown in the figures, the intermediate connecting member 300B has a plurality of first wirings arranged on the insulating substrate 311 and a plurality of second wirings arranged on the insulating substrate 312. The plurality of first wirings are arranged at intervals from each other in the X direction, and the plurality of second wirings are arranged at intervals from each other in the X direction. The plurality of first wirings are arranged on the main surface 3112 of the insulating substrate 311, similar to the first embodiment. Multiple second wirings are arranged on the main surface 3122 of the insulating substrate 312, similar to the first embodiment. The signal wiring 330S32 shown in Figure 9(a) is, for example, one of the multiple second wirings.

[0101] As shown in Figure 9(a), the signal wiring 330S32 is joined to the signal pad 225S1 by a connecting member 352S1. The end face 309U of the metal layer 309 is joined to the ground pad 225G1 of the wiring board 221 by a connecting member 352GB1. None of the multiple first wirings or multiple second wirings of the intermediate connecting member 300B are joined to the ground pad 225G1.

[0102] Furthermore, as shown in Figure 9(b), the end face 309U of the metal layer 309 is joined to the ground pad 225G2 of the wiring board 221 by a joining member 352GB2. None of the multiple first wires or multiple second wires of the intermediate connecting member 300B are joined to the ground pad 225G2.

[0103] Even with the above configuration, noise in the transmitted signal is reduced, and the quality of the transmitted signal is improved. Furthermore, the connection structure between the intermediate connecting member 300B and the wiring board 211 shown in Figure 2(b) may be the same as that shown in Figures 9(a) and 9(b).

[0104] (Example 1) A specific example of the manufacturing method of the imaging module 200 described in the first embodiment will now be explained. The thickness of the metal layer 309 in the Y direction was 0.2 mm. The intermediate connecting member 300 was in the shape of a strip with a length of 41.0 mm in the X direction, a width (thickness) of 1.0 mm in the Y direction, and a height of 1.8 mm in the Z direction. The pitch of the multiple wirings 3301 in the X direction and the pitch of the multiple wirings 3302 in the X direction was 0.4 mm. The total number of multiple wirings 330 was 140. A substrate with a low coefficient of thermal expansion was used for the insulating substrate 310. The external dimensions of the insulating substrate 310 were a length of 41.0 mm in the X direction, a height of 1.8 mm in the Z direction, and a thickness of 0.4 mm in the Y direction. Each wiring 330 was made of copper, with a thickness of 0.015 mm and a width of 0.2 mm. The number of multiple wirings 3301 was 70, and the number of multiple wirings 3302 was 70. The pitch of the wiring 330 in the X direction was set to 0.4 mm. A copper plate with a length of 41.0 mm in the X direction, a height of 1.8 mm in the Z direction, and a thickness of 0.2 mm in the Y direction was used as the metal layer 309. This metal layer 309 was sandwiched and bonded between insulating substrates 311 and 312, and the thickness of the intermediate connecting member 300 was set to 1.0 mm. An intermediate connecting member 300 with the above configuration was prepared.

[0105] A wiring board 211, as shown in Figure 6(a), was prepared. Solder resist (not shown) is formed on the main surface 2111 of the wiring board 211, partially covering each pad 215 to 217. Openings are formed in the solder resist at positions corresponding to each pad 215 to 217, exposing a portion of each pad 215 to 217.

[0106] FR-4 was used for the insulating substrate 210 of the wiring board 211. The external dimensions of the wiring board 211 in plan view were 50.0 mm × 50.0 mm. Electronic components such as capacitors and resistors (not shown) were pre-mounted on the main surface 2112 of the wiring board 211. The material of each pad 215 to 217 of the wiring board 211 was copper. Pads 215, excluding ground pads 215G1 and 215G2 to which the intermediate connecting member 300 is connected, had a width of 0.2 mm and a length of 0.3 mm. Pads 215 were arranged at a pitch of 0.4 mm. Pads 216 and 217 had a width of 0.2 mm and a length of 0.2 mm. Ground pad 215G1 had a width of 0.2 mm. m It was m, and the length was 0.6 mm. The ground pad 215G2 was 0.2 m It was m long and 1.2 mm in length.

[0107] As shown in Figure 6(b), each conductive paste PA was screen printed onto each pad 215-217 of the wiring board 211. A printing plate with a thickness of 0.02 mm was used for screen printing. The conductive paste PA was a solder paste containing Sn-Ag-Cu solder powder and flux. The alloy composition of the solder powder contained in the solder paste was tin-silver-3-copper-3, and the melting point of the solder powder was 220°C. The average particle size of the solder powder was 40 μm.

[0108] A memory module 212 with pre-attached solder balls on its back was prepared. Each pad 216 on the wiring board 211 was positioned to correspond to the solder balls on the memory module 212. The external dimensions of the memory module 212 were 16.0 mm in length, 16.0 mm in width, and 1.6 mm in height. Four intermediate connecting members 300 were also prepared.

[0109] As shown in Figure 6(c), conductive paste PA The memory 212, electronic components 213, and intermediate connecting members 300 were placed on the supplied wiring board 211 using a mounter. The four intermediate connecting members 300 were placed on the wiring board 211 so as to surround the memory 212 and electronic components 213.

[0110] For each of the four intermediate connecting members 300, the end face 330L of each wiring 330 was aligned with each pad 215 of the wiring board 211, and each intermediate connecting member 300 was placed on the wiring board 211. In addition, the solder balls (not shown) of the memory 212 were aligned with the pads 216 of the wiring board 211, and the memory 212 was placed on the wiring board 211. The width of the insulating substrate 310 of the intermediate connecting member 300 was 1.0 mm, and the intermediate connecting member 300 was self-supporting on the wiring board 211.

[0111] Next, the wiring board 211 on which these components were placed was placed in a reflow oven, and the conductive paste PA was heated to a temperature above the melting point of the solder powder. After the solder powder melted and the molten solder agglomerated, the molten solder was cooled to a temperature below the melting point of the solder and solidified. As a result, the memory 212, electronic components 213, and intermediate connecting member 300 were bonded to the wiring board 211, as shown in Figure 6(d).

[0112] Next, as shown in Figure 7(a), conductive paste PB was screen printed onto each pad 225 of the wiring board 221. The conductive paste PB was a solder paste containing Sn-Ag-Cu solder powder and flux. The alloy composition of the solder powder contained in the solder paste was tin-silver-3-copper-3, and the melting point of the solder powder was 220°C. The average particle size of the solder powder was 40 μm.

[0113] Next, the pads 225 of the wiring board 221, to which conductive paste PB was supplied, were aligned with the end faces 330U of each wiring 330 of each intermediate connecting member 300, and the wiring board 221 was placed on the four intermediate connecting members 300. Solder resist (not shown) is formed on the main surface 2212 of the wiring board 221, partially covering each pad 225. Openings are formed in the solder resist at positions corresponding to each pad 225, exposing a portion of each pad 225.

[0114] The insulating substrate 220 of the wiring board 221 was made of an insulating substrate with a low coefficient of thermal expansion. The external dimensions of the wiring board 221 in plan view were 52.0 mm × 52.0 mm. The material of each pad 225 of the wiring board 221 was copper. The pads 225 to which the intermediate connecting member 300 was connected were 0.2 mm wide and 0.3 mm long, and were arranged at a pitch of 0.4 mm.

[0115] Next, as shown in Figure 7(b), the mounted product with the wiring board 221 mounted on the intermediate connecting member 300 was placed in a reflow oven, and the conductive paste PB was heated to a temperature above the melting point of the solder powder. After the solder powder melted and the molten solder agglomerated, the molten solder was cooled to a temperature below the melting point of the solder and solidified. This joined the wiring board 221 to the intermediate connecting member 300.

[0116] Next, as shown in Figure 7(c), the image sensor 222, frame 223, and LID 224 were mounted on the wiring board 221 to fabricate a circuit unit 202 and obtain an imaging module 200. The imaging module 200 fabricated through the above process had no solder joint defects and fully guaranteed the optical performance of the image sensor 222. In addition, the metal layer 309 of the intermediate connecting member 300 reduced noise in the transmitted signal and improved the quality of the transmitted signal.

[0117] The present invention is not limited to the embodiments described above, and many modifications are possible within the technical concept of the present invention. Furthermore, the effects described in the embodiments are merely a list of the most preferred effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments.

[0118] In the embodiments described above, the example of an electronic device being a digital camera was used, but the invention is not limited to this. For example, the electronic device may be a mobile communication device. For example, the electronic device may be an information device such as a smartphone or a personal computer, or a communication device such as a modem or a router. Alternatively, the electronic device may be office equipment such as a printer or a copier, medical equipment such as a radiographer, magnetograph, ultrasound machine, or endoscope, industrial equipment such as a robot or semiconductor manufacturing equipment, or transportation equipment such as a vehicle, airplane, or ship. When wiring is provided in the limited space within the housing of an electronic device, using the intermediate connecting member 300 makes it possible to miniaturize and increase the density of the electronic device. The electronic module of the present invention is applicable to all electronic devices. [Explanation of Symbols]

[0119] 211... Wiring board (first wiring board), 221... Wiring board (second wiring board), 300... Intermediate connecting member, 309... Metal layer, 310... Insulating substrate (insulator), 3301... Wiring (first wiring), 3302... Wiring (second wiring)

Claims

1. First wiring board and The first wiring board and the second wiring board, which is spaced apart in the first direction, The device comprises an intermediate connecting member disposed between the first wiring board and the second wiring board, The aforementioned intermediate connecting member is Insulator and, Supported by the insulator, a plurality of first wirings are arranged at intervals from each other in a second direction intersecting the first direction, A plurality of second wirings supported by the insulator and arranged at intervals from each other in the second direction, The device includes a metal layer that is sandwiched and supported by the insulator and positioned between the plurality of first wirings and the plurality of second wirings so as to face the plurality of first wirings and the plurality of second wirings in a third direction intersecting the first direction and the second direction, The plurality of first wirings include a first ground wiring and a first signal wiring, The first ground wiring is joined to the first ground pad of the first wiring board by a conductive first bonding member. The first signal wiring is joined to the first signal pad of the first wiring board by a conductive second bonding member. The metal layer sandwiched between the insulators extends from one end to the other end of the insulators in the first direction and is joined to the first ground pad by the first joining member. The first joining member is a continuous solder, including a portion joined to the first ground wiring and a portion of the metal layer sandwiched between the insulators that is joined to the first ground pad. An electronic module characterized by the following features.

2. The second joining member includes a portion that overlaps the metal layer in the third direction, The electronic module according to feature 1.

3. The distance between the first signal wiring and the metal layer is less than or equal to the distance between the two closest wirings among the plurality of first wirings and the plurality of second wirings. The electronic module according to feature 1.

4. The distance between the first signal wiring and the metal layer is less than or equal to the distance between two adjacent first wirings among the plurality of first wirings. The electronic module according to claim 2 or 3, characterized by the above.

5. The plurality of first wirings include a second ground wiring, The plurality of second wirings include a third ground wiring that overlaps the second ground wiring in the third direction. The second ground wiring and the third ground wiring are joined to the second ground pad of the first wiring board by a conductive third bonding member. The metal layer sandwiched between the insulators is joined to the second ground pad by the third joining member. The third joining member is a continuous solder, including a portion joined to the second ground wiring, a portion joined to the third ground wiring, and a portion of the metal layer sandwiched between the insulators that is joined to the second ground pad. The electronic module according to any one of claims 1 to 4.

6. The plurality of second wirings include a second signal wiring that overlaps the first ground wiring in the third direction, The second signal wiring is joined to the second signal pad of the first wiring board by a conductive fourth bonding member. The electronic module according to any one of claims 1 to 5.

7. The plurality of second wirings include a third signal wiring that overlaps the first signal wiring in the third direction, The third signal wiring is joined to the third signal pad of the first wiring board by a conductive fifth bonding member. The electronic module according to any one of claims 1 to 6.

8. The plurality of first wirings include a fourth ground wiring and a fourth signal wiring, The fourth ground wiring is joined to the third ground pad of the second wiring board by a conductive sixth connecting member. The fourth signal wiring is joined to the fourth signal pad of the second wiring board by a conductive seventh bonding member. The metal layer sandwiched between the insulators is joined to the third ground pad by the sixth joining member. The sixth joining member is a continuous solder, including a portion joined to the fourth ground wiring and a portion of the metal layer sandwiched between the insulators that is joined to the third ground pad. The electronic module according to any one of claims 1 to 7.

9. The plurality of first wirings include a fifth ground wiring, The plurality of second wirings include a sixth ground wiring that overlaps the fifth ground wiring in the third direction. The fifth ground wiring and the sixth ground wiring are joined to the fourth ground pad of the second wiring board by a conductive eighth bonding member. The metal layer sandwiched between the insulators is joined to the fourth ground pad by the eighth joining member. The eighth joining member is a continuous solder, including a portion joined to the fifth ground wiring, a portion joined to the sixth ground wiring, and a portion of the metal layer sandwiched between the insulators that is joined to the fourth ground pad. The electronic module according to any one of claims 1 to 8.

10. The plurality of second wirings include a fifth signal wiring that overlaps the fourth ground wiring in the third direction, and a sixth signal wiring that overlaps the fourth signal wiring in the third direction, The fifth signal wiring is joined to the fifth signal pad of the second wiring board by a conductive ninth bonding member, and the sixth signal wiring is joined to the sixth signal pad of the second wiring board by a conductive tenth bonding member. The electronic module according to feature 8.

11. The insulator includes a first insulating substrate and a second insulating substrate. The metal layer is arranged between the first insulating substrate and the second insulating substrate in the third direction. The first insulating substrate is placed between the first wiring and the metal layer. The second insulating substrate is placed between the second wiring and the metal layer. The electronic module according to any one of claims 1 to 10.

12. The insulator includes a first insulating substrate and a second insulating substrate, The metal layer is arranged between the first insulating substrate and the second insulating substrate in the third direction. The plurality of first wirings are arranged between the first insulating substrate and the metal layer. The plurality of second wirings are arranged between the second insulating substrate and the metal layer. The electronic module according to any one of claims 1 to 10.

13. A first semiconductor element mounted on the first wiring board, The invention further comprises a second semiconductor element mounted on the second wiring board, The electronic module according to any one of claims 1 to 12.

14. The first semiconductor element is mounted on the surface of the first wiring board facing the second wiring board. The electronic module according to feature 13.

15. The second semiconductor element is mounted on the back side of the second wiring board with respect to the side facing the first wiring board. The electronic module according to feature 13 or 14.

16. The second semiconductor element is an image sensor. The electronic module according to any one of claims 13 to 15, characterized in that it is the same as described in the previous claim.

17. The first semiconductor device is a memory. The electronic module according to any one of claims 13 to 16.

18. First wiring board and The first wiring board and the second wiring board, which is spaced apart in the first direction, The device comprises an intermediate connecting member disposed between the first wiring board and the second wiring board, The aforementioned intermediate connecting member is Insulator and, Supported by the insulator, a plurality of first wirings are arranged at intervals from each other in a second direction intersecting the first direction, A plurality of second wirings supported by the insulator and arranged at intervals from each other in the second direction, The device comprises a metal layer supported by the insulator and positioned between the plurality of first wirings and the plurality of second wirings so as to face the plurality of first wirings and the plurality of second wirings in a third direction intersecting the first direction and the second direction, The plurality of first wirings and the plurality of second wirings include signal wiring used for signal transmission. The plurality of first wirings and the plurality of second wirings are spaced apart from both ends of the insulator in the second direction. The distance between the signal wiring and the metal layer is less than or equal to the distance between the two closest wirings among the plurality of first wirings and the plurality of second wirings. An electronic module characterized by the following features.

19. A method for manufacturing an electronic module according to any one of claims 1 to 17, The steps include preparing the first wiring board, the second wiring board, and the intermediate connecting member, The process includes joining the portion of the intermediate connecting member's metal layer sandwiched between the insulators to one of the first wiring board and the second wiring board using a first joining member. The metal layer of the intermediate connecting member prepared in the above preparation step has an end face exposed from the insulator on the surface of the intermediate connecting member that faces one of the first wiring board and the second wiring board. A method for manufacturing an electronic module, characterized by the following:

20. The casing and The enclosure comprises an electronic module according to any one of claims 1 to 18, disposed inside the enclosure, An electronic device characterized by the following features.

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