JP6644743B2 - Circuit board and semiconductor module - Google Patents

Description

  The present invention relates to a circuit board having a flexible part and a rigid part, and a semiconductor module having a semiconductor element mounted on the circuit board.

  A module board of a mobile device having a camera function or the like is required to be further thinner in order to realize multifunctional and thinner parts. Among them, when using a flexible board or the like for connection between the main board and the module, a technique using a connector or a technique of bonding the module board and the flexible board are known. Has become an issue. Therefore, adoption of a composite circuit board (rigid-flexible board) having a rigid portion provided on a flexible board is progressing.

  For example, including a deformable flexible part, an insulating base and an electric circuit formed on the insulating base, a rigid part to which the flexible part is connected, and a peripheral part of the insulating base formed inside the insulating base. There is disclosed a circuit board provided with a stress and a reinforcing member formed of an insulating resin having higher rigidity than an insulating base material (for example, see Patent Document 1).

JP 2011-108929 A

  However, when a plurality of semiconductor elements such as solid-state imaging devices are mounted on the rigid portion, if the flatness of the region in which the devices are mounted is not sufficient, for example, optical adjustment of each of the plurality of solid-state imaging devices becomes difficult. In addition, handling of a circuit board having a plurality of solid-state imaging devices becomes complicated.

  In view of the circumstances as described above, an object of the present invention is to provide a circuit board and a semiconductor module in which the flatness of a region where an element is mounted is improved.

In order to achieve the above object, a circuit board according to one embodiment of the present invention includes a wiring substrate and a reinforcing portion. The reinforcing portion is a plate-shaped reinforcing member buried in a first portion of the wiring base material and having a first main surface and a second main surface opposite to the first main surface; The semiconductor device includes a wiring layer provided on the second main surface and an element mounting portion on which the plurality of semiconductor elements are mounted directly or indirectly on the first main surface.
With such a circuit board, an element mounting portion on which a plurality of semiconductor elements are directly or indirectly mounted is arranged on a plate-like reinforcing member embedded in a wiring base. Is improved. Thereby, the step of each of the plurality of semiconductor elements is reduced. As a result, handling of the semiconductor element mounted on the element mounting portion becomes easy. Furthermore, since the plate-shaped reinforcing member is integrally formed, the heat dissipation effect of the reinforcing member is improved.

In the above-mentioned circuit board, when each of the reinforcing member and the element mounting portion is projected in the thickness direction of the reinforcing portion, the element mounting portion may be included in a region of the reinforcing member.
With such a circuit board, when each of the reinforcing member and the element mounting portion is projected in the thickness direction of the reinforcing portion, the element mounting portion falls within the main surface of the reinforcing member, so that the flatness of the element mounting portion is improved. I do. Further, since the reinforcing member including the element mounting portion is integrally formed, the heat radiation effect of the reinforcing member is improved.

In the above-described circuit board, the reinforcing portion may further include a bonding pad electrically connected to each of the plurality of semiconductor elements, and the bonding pad may include the wiring on the first main surface. It may be arranged in layers.
In such a circuit board, since a plurality of bonding pads are arranged on the reinforcing member, the strength of the base of each bonding pad increases. This suppresses the displacement of the bonding pad when bonding the bonding wire to the bonding pad.

In the above circuit board, the wiring base may have a second portion extending from the first portion, and the second portion may have flexibility.
With such a circuit board, the circuit board has a flexible portion having flexibility in addition to the rigid portion.

In the above circuit board, the element mounting portion may be arranged on a surface of the wiring layer on the first main surface.
With such a circuit board, an element mounting portion on which a plurality of semiconductor elements are indirectly mounted is arranged on a plate-like reinforcing member embedded in a wiring base, so that the flatness of the element mounting portion is improved. Is improved.

In the above-described circuit board, the wiring layer may have a recess exposing the first main surface of the reinforcing member, and the plurality of semiconductor elements may be arranged in the recess.
With such a circuit board, an element mounting portion on which a plurality of semiconductor elements are directly mounted is arranged on a plate-like reinforcing member embedded in a wiring base, so that the flatness of the element mounting portion is improved. Is further improved. Further, the heat radiation effect of the plurality of semiconductor elements is improved.

In the above circuit board, the recess may be divided into a plurality of portions, and the plurality of semiconductor elements may be individually accommodated in the plurality of divided recesses.
With such a circuit board, the plurality of semiconductor elements are individually mounted in the plurality of divided recesses, so that bonding pads can be formed between the plurality of semiconductor elements.

In order to achieve the above object, a semiconductor module according to one embodiment of the present invention includes a wiring base, a circuit board, and a plurality of semiconductor elements. The circuit board has a reinforcing portion, and the reinforcing portion is a plate-like member buried in a first portion of the wiring substrate and having a first main surface and a second main surface opposite to the first main surface. , A wiring layer provided on the first main surface and the second main surface, and an element mounting portion on which a plurality of elements are mounted directly or indirectly on the first main surface. . The plurality of semiconductor elements are mounted on the element mounting part.
In such a semiconductor module, an element mounting portion on which a plurality of elements are directly or indirectly mounted is arranged on a plate-like reinforcing member embedded in a wiring base material. The flatness is improved. Furthermore, since the plate-shaped reinforcing member is integrally formed, the heat dissipation effect of the reinforcing member is improved.

In the above-described semiconductor module, each of the plurality of semiconductor elements may be a solid-state imaging device.
With such a semiconductor module, even when a plurality of solid-state imaging elements are mounted on the element mounting portion, optical adjustment of each of the plurality of solid-state imaging elements becomes easy.

  As described above, according to the present invention, there are provided a circuit board and a semiconductor module in which the flatness of a region in which elements are mounted is improved.

FIG. 2 is a schematic plan view illustrating a configuration of a circuit board according to the first embodiment. FIG. 1A is a sectional view taken along line AA in FIG. FIG. 2B is a sectional view taken along line BB in FIG. FIG. 9 is a schematic cross-sectional view of a main step for explaining the method for manufacturing a circuit board. FIG. 9 is a schematic cross-sectional view of a main step for explaining the method for manufacturing a circuit board. It is a schematic sectional view showing the composition of the circuit board concerning a 2nd embodiment. It is a schematic sectional view showing the composition of the circuit board concerning a 3rd embodiment. It is a schematic sectional view showing the composition of the circuit board concerning a 4th embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, XYZ axis coordinates may be introduced.

  (1st Embodiment)

FIG. 1 is a schematic plan view showing the configuration of the circuit board according to the first embodiment.
FIG. 2A is a sectional view taken along the line AA in FIG. FIG. 2B is a sectional view taken along line BB in FIG.
In each of the drawings, the X axis, the Y axis, and the Z axis indicate three orthogonal directions that are orthogonal to each other, and the Z axis direction corresponds to the thickness direction of the circuit board 1.

  [Circuit board]

  As shown in FIG. 1, the circuit board 1 of the present embodiment has a first board main body 10 and a second board main body 20. The circuit board 1 is typically configured integrally with the control board 30, but may be configured as a separate component from the control board 30.

  Two semiconductor elements 271 and 272 are mounted on the surface of the second board main body 20 of the circuit board 1. The semiconductor elements 271 and 272 are, for example, solid-state imaging devices (optical sensors) such as a charge coupled device (CCD) and a complementary MOS (CMOS). The semiconductor elements 271 and 272 are mounted on the second substrate main body 20 such that the imaging surfaces 271a and 272a of the semiconductor elements 271 and 272 are parallel to each other. The reinforcement member 23 is disposed below the two semiconductor elements 271, 272.

  (First substrate body)

  As shown in FIGS. 2A and 2B, the first substrate main body 10 connects between the second substrate main body 20 and the control substrate 30. The first substrate main body 10 includes a flexible wiring substrate 11 and forms a flexible portion of the circuit board 1. The flexible wiring substrate 11 typically has a longitudinal direction in the X-axis direction and a width direction in the Y-axis direction. In the flexible wiring base material 11, a first portion (first end 11a side) in the longitudinal direction is incorporated into the second substrate body 20, and a second portion (second end 11b) extending from the first portion is provided. Side) is connected to the control board 30.

  As shown in FIGS. 2A and 2B, the flexible wiring base 11 includes a resin core 110, wiring layers 111 and 112 provided on both surfaces of the resin core 110, and wiring layers 111 and 112. This is a laminate having insulating layers 113 and 114 to cover.

  The resin core 110 is made of, for example, a single-layer or multi-layer flexible plastic film such as polyimide or polyethylene terephthalate. The wiring layers 111 and 112 are typically made of a metal material such as copper or aluminum. Further, the insulating layers 113 and 114 are made of a flexible plastic film such as polyimide having an adhesive layer.

  The wiring layer 111 is electrically connected to the wiring layer 112 via through holes or vias provided at appropriate positions on the resin core 110. The wiring layers of the flexible wiring substrate 11 are not limited to the two layers illustrated, but may be one layer or three or more layers.

  (2nd substrate body)

  The second substrate body 20 has a wiring layer 28, a reinforcing member 23, and a first end 11 a of the flexible wiring base 11. That is, the first end 11 a of the flexible wiring base 11 constitutes a core of the second substrate main body 20 together with the reinforcing member 23. In the circuit board 1, the reinforcing portion 12 is configured by the wiring layer 28 and the reinforcing member 23. The reinforcing part 12 is a rigid part in the circuit board 1. Further, in the present embodiment, the portion of the flexible wiring substrate 11 at the first end 11a incorporated in the second substrate main body 20 may be simply referred to as the wiring substrate 11.

  The wiring layer 28 includes insulating layers 211 and 212, wirings 221 and 222, and insulating layers 251 and 252. The wiring layer 28 includes a first main surface 11u (upper surface) and a second main surface 11d (lower surface) of the first end 11a, and a first main surface 23u (upper surface) and a second main surface 23d (lower surface) of the reinforcing member 23. ).

  When the insulating layer 211 is disposed on the first main surface 23u side of the reinforcing member 23, the insulating layer 212 is disposed on the second main surface 23d side of the reinforcing member 23. The insulating layers 211 and 212 form the outer shape of the second substrate main body 20, and the planar shape is typically formed in a rectangular shape elongated in the X-axis direction as shown in FIG. The size of the insulating layers 211 and 212 is not particularly limited. For example, the long side is 10 to 30 mm, the short side is 10 to 20 mm, and the thickness is 0.2 to 0.5 mm. As shown in FIG. 1, the first end 11a of the flexible wiring base 11 is formed in the same shape and size as the second substrate main body 20, but is not limited thereto. It may be formed larger or smaller than that.

  The insulating layers 211 and 212 are made of a synthetic resin material. As the synthetic resin material, for example, a general-purpose thermosetting resin material such as an epoxy resin, a phenol resin, and a BT resin is used. These synthetic resin materials may contain, for example, a filler (filler) such as glass fiber, glass cloth, or oxide particles in order to impart desired mechanical strength. The insulating layers 211 and 212 may be made of the same resin material, or may be made of mutually different resin materials.

  The wirings 221 and 222 are so-called conductor patterns. Further, the wiring 221 and the wiring 222 are electrically connected by an interlayer connection part 223. The wirings 221 and 222 are electrically connected to the flexible wiring base 11 forming the first substrate main body 10.

  The wirings 221 and 222 are formed on the surfaces of the insulating layers 211 and 212, and a part thereof is electrically connected to the reinforcing member 23 via vias formed at appropriate positions on the insulating layers 211 and 212. The reinforcing member 23 may be configured as a part of one of the wirings 221 and 222, and may be used as a part of a grounding wiring, for example. In particular, when the reinforcing member 23 is configured with the ground potential, the trouble of routing the grounding wiring in the circuit board 1 while avoiding the reinforcing member 23 can be omitted, and the reinforcing member 23 can be used outside the circuit board 1 or the semiconductor element 271, The electromagnetic wave from 272 is shielded. Further, the reinforcing member 23 may be used as a heat-radiating component of a semiconductor element mounted on the second substrate main body 20. The distance between the reinforcing member 23 and the semiconductor elements 271, 272 in the Z-axis direction is, for example, 15 μm to 100 μm, but is not limited to this value.

  The wirings 221 and 222 are typically made of a metal material such as copper or aluminum or a cured product of a metal paste. The wirings 221 and 222 are mainly electrically connected to the bonding pads 261 of the semiconductor elements 271 and 272 mounted on the surface of the second substrate main body 20 or electrically connected to the flexible wiring base 11. Insulating layers 251 and 252 are provided on the surfaces of the wirings 221 and 222 that constitute a rewiring layer and the like connected to the wiring. Each of the insulating layers 251 and 252 may have an opening at an appropriate position where a part of the surface of the wiring 221 or 222 is exposed.

  The wirings 221 and 222 are not limited to a single layer structure, and may have a multilayer structure. Further, the present invention is not limited to the case where both the wirings 221 and 222 are provided, and only one of them may be provided.

  The wirings 221 and 222 are covered with insulating layers 251 and 252. The bonding pad 261 is arranged on the wiring layer 28 on the first main surface 23u of the reinforcing member 23. For example, the bonding pad 261 is disposed on the insulating layer 251.

  The reinforcing member 23 is embedded in the first end 11 a of the flexible wiring base 11. The reinforcing member 23 is a plate-like reinforcing member having a first main surface 23u and a second main surface 23u. The reinforcing member 23 is for giving a desired strength to the second substrate main body 20.

  The reinforcing member 23 is made of, for example, metal or ceramic. However, from the viewpoint of the electrical characteristics and heat dissipation of the circuit board 1, the reinforcing member 23 is preferably made of metal. For example, the reinforcing member 23 is made of a good electrical or thermal conductor, typically made of copper (Cu), but may be made of another metal material such as a copper alloy, aluminum, or an aluminum alloy. May be done.

  The planar shape of the reinforcing member 23 is not particularly limited. For example, the reinforcing member 23 is formed in a rectangular shape large enough to be accommodated in the first end 11a of the flexible wiring base material 11. The size of the reinforcing member 23 is not particularly limited. For example, each side has a length of 5 mm to 20 mm and a thickness of 0.1 mm to 0.4 mm.

  Since the reinforcing member 23 is formed to have a size that can cover almost the entire area of the first end 11a of the flexible wiring base 11, the reinforcing member 23 has an effect as a core material of the second substrate body 20. Can be achieved. Further, since the entire reinforcing member 23 is housed inside the first end 11a, the reinforcing member 23 is prevented from being exposed from the peripheral edge of the first end 11a, and the peripheral edge of the second substrate body 20 is prevented from being exposed. Insulation can be ensured.

  The thickness of the reinforcing member 23 is not particularly limited, and is equal to the thickness of the flexible wiring substrate 11 in the present embodiment. Since both surfaces of the reinforcing member 23 are covered with the insulating layers 211 and 212, the exposure of the reinforcing member 23 from both surfaces of the second substrate body 20 is prevented.

  The reinforcing member 23 is housed in a housing 213 formed in the plane of the first end 11a of the flexible wiring base material 11. The accommodation portion 213 is formed of a bottomed or non-bottomed concave portion having a size capable of accommodating the reinforcing member 23, and in the present embodiment, is configured by a rectangular opening (unbottomed concave portion) penetrating the first end portion 11a. Is done.

  The reinforcing member 23 may be provided with a groove 231 penetrating the plane thereof. For example, the reinforcing member 23 includes a first insulating material 241 filled inside the groove 231 and a second insulating material 242 filled between the outer peripheral surface of the reinforcing member 23 and the inner peripheral surface of the housing portion 213. Via the first end 11a.

  Further, the reinforcing member 23 may be provided with one or more through holes 232 penetrating in the plane. For example, the through hole 232 is formed at an appropriate position in the plane of the reinforcing member 23, and is provided between the peripheral portion of the reinforcing member 23 and the region where the groove 231 is formed. The through hole 232 is formed as a round hole large enough to accommodate the interlayer connection part 223. The interlayer connection portion 223 is typically formed by copper plating formed on the inner peripheral surface of the through hole 232 with an insulating layer interposed therebetween. The insulating layer is made of, for example, a first insulating material 241.

  In the present embodiment, the first insulating material 241 is formed of a resin material having a smaller coefficient of thermal expansion and a higher elastic modulus than the resin material forming the insulating layers 211 and 212.

  Since the first insulating material 241 is made of a resin material having a smaller coefficient of thermal expansion than the insulating layers 211 and 212, the adhesion between the housing portion 213 and the reinforcing member 23 can be ensured. Warpage can be suppressed. Further, since the first insulating material 241 is made of a resin material having a higher elastic modulus than the insulating layers 211 and 212, the rigidity of the first insulating material 241 is increased, and the strength of the second substrate body 20 is improved. be able to.

  The material forming the first insulating material 241 is not particularly limited, and may be, for example, the same material as the resin material forming the insulating layers 211 and 212. In this case, the first insulating material 241 having a smaller thermal expansion coefficient and a higher elastic modulus than the insulating layers 211 and 212 can be formed by increasing the content of the filler more than the insulating layers 211 and 212.

  On the other hand, the second insulating material 242 is made of a material having a lower elastic modulus than the resin material forming the insulating layers 211 and 212. Thereby, the bending stress applied to the peripheral portion of the second substrate main body 20 is reduced by the second insulating material 242, so that the peeling of the reinforcing member 23 from the housing portion 213 can be suppressed. Further, the second insulating material 242 may be made of a material having a lower water absorption than the insulating layers 211 and 212. Thus, volume expansion or swelling of the second insulating material 242 due to water absorption is suppressed.

  The material forming the second insulating material 242 is not particularly limited, but a material having a high affinity with the flexible wiring base material 11 is preferable, and examples thereof include epoxy, polyimide, liquid crystal polymer, BT resin, and PPS. .

  The second insulating material 242 is filled between the outer peripheral surface of the reinforcing member 23 and the inner peripheral surface of the housing 213. The second insulating material 242 does not need to be provided over the entire outer peripheral surface of the reinforcing member 23, and may be provided at least on the second end 11b side of the flexible wiring base material 11. Thereby, for example, the tensile stress or the like from the first substrate body 10 can be absorbed or reduced by the second insulating material 242, and the breakage of the second substrate body 20 and the detachment of the reinforcing portion 12 from the first end 11a can be suppressed. It becomes possible.

  Further, the present invention is not limited to the case where the entire region of the one end portion between the reinforcing member 23 and the housing portion 213 is filled with the second insulating material 242, and as shown in FIGS. A laminated portion 243 of the insulating material 241 and the second insulating material 242 may be provided. In this case, since the region has appropriate rigidity and appropriate elasticity, the connection reliability between the flexible wiring base material 11 and the reinforcing portion 12 can be improved.

  Note that the second insulating material 242 may be omitted according to required characteristics and specifications, and the first insulating material 241 is used instead of the second insulating material 242 between the reinforcing member 23 and the housing portion 213. May be filled. Further, the stacked portion 243 may be omitted as necessary, and the entire region of the one end may be filled with the first insulating material 241 or the second insulating material 242.

  Further, the circuit board 1 according to the present embodiment has an element mounting section 40. The element mounting portion 40 is disposed on the surface of the wiring layer 28 on the first main surface 23u of the reinforcing member 23. That is, the element mounting portion 40 is located on the first main surface 23u of the reinforcing member 23. A plurality of semiconductor elements 271 and 272 are indirectly mounted on the reinforcing member 23 via a wiring layer 28. The semiconductor elements 271, 272 are, for example, solid-state imaging devices. Further, each of the plurality of semiconductor elements 271, 272 is electrically connected to a bonding pad 261 via a bonding wire 265. A semiconductor module including the circuit board 1 and the plurality of semiconductor elements 271 and 272 can be provided.

  The planar shape of the element mounting portion 40 is not particularly limited, and is set according to the planar shape of the reinforcing member 23. For example, when each of the reinforcing member 23 and the element mounting portion 40 is projected in the thickness direction (Z-axis direction) of the reinforcing portion 12, the element mounting portion 40 is included in the region of the reinforcing member 23. For example, the element mounting portion 40 is formed in a rectangular shape large enough to be accommodated inside the reinforcing member 23. The size of the element mounting portion 40 is not particularly limited, and for example, the length of each side is set to 5 mm to 20 mm or less.

  (Control board)

  The control board 30 corresponds to a main board on which an integrated circuit such as an IC and its peripheral components are mounted, and is electrically connected to the second board main body 20 via the first board main body 10. The control board 30 is typically composed of a double-sided board having a larger area than the second board body 20.

  The control board 30 is composed of a laminate of the second end 11b of the flexible wiring base 11 and the multilayer wiring sections 31 and 32 provided on both sides thereof. The multilayer wiring portions 31 and 32 are typically manufactured by a build-up method. The interlayer insulating films forming the multilayer wiring portions 31 and 32 may be made of a glass epoxy-based material having rigidity. In this case, the control board 30 is formed as a rigid board.

  [Circuit board manufacturing method]

  A method for manufacturing the circuit board 1 will be described.

  FIGS. 3A to 4D are schematic cross-sectional views of main steps for describing a method of manufacturing a circuit board.

  First, as shown in FIGS. 3A and 3B, the reinforcing member 23 is accommodated in a predetermined region on the first end 11 a side of the flexible wiring base 11 constituting the first substrate body 10. Is formed. The method for forming the housing portion 213 is not particularly limited, and an appropriate method such as mechanical processing such as punching or cutting, or laser processing can be employed.

  Subsequently, as shown in FIG. 3C, an insulating layer 212 that covers the housing portion 213 is formed on one surface (the lower surface in the figure) of the flexible wiring base material 11. The method for forming the insulating layer 212 is not particularly limited, and an appropriate method such as a coating method, a transfer method, and a lamination method can be employed.

  Subsequently, as shown in FIG. 3D, a material forming the second insulating material 242 is applied to the inner peripheral surface of the housing portion 213 and the boundary with the insulating layer 212. Thereafter, as shown in FIG. 4A, the reinforcing member 23 is disposed on the insulating layer 212 in the housing 213, and the reinforcing member 23 is disposed between the outer peripheral surface of the reinforcing member 23 and the inner peripheral surface of the housing 213. Two insulating materials 242 are filled to a predetermined height. In this case, a part of the second insulating material 242 may be interposed between the reinforcing member 23 and the insulating layer 212.

  Next, as shown in FIG. 4B, the material forming the first insulating material 241 is filled in the groove 231 and the through hole 232 of the reinforcing member 23. At this time, the first insulating material 241 is also provided in the gap between the outer circumferential surface of the reinforcing member 23, the inner circumferential surface of the housing portion 213, and the second insulating material 242, so that the first and second insulating materials 241 and 241 are provided. A laminated portion 243 having a laminated structure of 242 is formed.

  After that, an insulating layer 211 covering the reinforcing member 23 is formed on the other surface (the upper surface in the figure) of the flexible wiring base material 11. The method for forming the insulating layer 211 is not particularly limited, and a method similar to the method for forming the insulating layer 212 can be employed.

  Subsequently, as shown in FIG. 4C, wirings 221 and 222 and an interlayer connection 223 are formed on the surfaces of the insulating layers 211 and 212. For the wirings 221 and 222, an appropriate pattern forming method such as a plating method and an etching method can be adopted, and a part thereof is connected to the reinforcing member 23 via vias formed in the insulating layers 211 and 212. The interlayer connection part 223 is formed by forming a through-hole in the first insulating material 241 filled in the through-hole 232 of the reinforcing member 23 and plating or growing a conductor layer on the inner wall surface or filling a conductor paste. It is formed.

  Subsequently, as shown in FIG. 4D, insulating layers 251 and 252 partially covering the insulating layers 211 and 212 are formed, respectively, and further, the insulating layer 211 in the formation region of the first substrate body 10 is formed. 212 is partially removed. Thus, the circuit board 1 including the first substrate body 10, the second substrate body 20, and the control substrate 30 is manufactured.

  Thereafter, a bonding pad 261 is formed on the element mounting portion 40 on the wiring layer 28, and the semiconductor elements 271 and 271 are mounted on the element mounting portion 40 via an adhesive, a double-sided tape, or the like (not shown) ( (FIGS. 2A and 2B). Further, the semiconductor elements 271 and 271 and the bonding pads 261 are electrically connected via the bonding wires 265 by wire bonding.

  In the circuit board 1 of the present embodiment configured as described above, the second board main body 20 has the plate-shaped reinforcing member 23 embedded in the first end 11a of the flexible wiring base material 11. Therefore, the strength of the second substrate body 20 is improved.

  Further, according to the circuit board 1, since the element mounting portion 40 is disposed on the reinforcing member 23 having an integral structure, the flatness of the element mounting portion 40 is improved.

  For example, when the reinforcing member is divided and the solid-state imaging devices are individually mounted on each of the divided reinforcing members, the height of each of the plurality of solid-state imaging devices may be shifted. In this case, optical adjustment of each of the plurality of solid-state imaging devices becomes difficult, and handling of a circuit board including the plurality of solid-state imaging devices becomes complicated.

  On the other hand, according to the circuit board 1, the element mounting portion 40 is provided on the plate-shaped reinforcing member 23 having an integral structure, and a plurality of solid-state imaging devices are arranged on the element mounting portion 40. This makes it difficult for the heights of the plurality of solid-state imaging devices to shift, and the imaging surfaces of the plurality of solid-state imaging devices are arranged in parallel to the first main surface 23u of the reinforcing member 23. This facilitates optical adjustment of the plurality of solid-state imaging devices. Further, if the reinforcing member 23 having an integral structure is disposed below the element mounting portion 40, the heat dissipation effect of the reinforcing member 23 is also improved, and a rise in the temperature of the plurality of solid-state imaging devices is suppressed.

  Further, in the circuit board 1, since the plurality of bonding pads 261 are arranged on the element mounting portion 40, the strength of the base of the bonding pads 261 is also increased. Thus, when bonding the bonding wire 265 to the bonding pad 261, the bonding pad 261 in contact with the bonding wire 265 is less likely to be displaced. Here, the displacement of the bonding pad 261 is, for example, sinking or lateral displacement of the bonding pad 261.

  (2nd Embodiment)

  FIG. 5 is a schematic sectional view illustrating the configuration of the circuit board according to the second embodiment. FIG. 5 corresponds to a sectional view taken along line BB in FIG.

  The circuit board 2 of the present embodiment is common to the first embodiment in having a first substrate main body 10 and a second substrate main body 20. However, the circuit board 2 is different from the first embodiment in that each of the semiconductor elements 271 and 272 is embedded in the wiring layer 28.

  In the present embodiment, the wiring layer 28 has a concave portion 281 from which the first main surface 23u of the reinforcing member 23 is exposed. The element mounting section 40 includes a recess 281. In the present embodiment, the bottom of the concave portion 281 becomes the element mounting surface.

  Each of the plurality of semiconductor elements 271 and 272 is collectively accommodated in the recess 281. The semiconductor element 271 may be housed in the recess 281 at least partially from the bottom surface, or may be housed so as to be completely buried in the recess 281. Similarly, semiconductor element 272 may be housed in recess 281 at least partially from the bottom surface, or may be housed so as to be completely buried in recess 281.

  That is, in the circuit board 2, the plurality of semiconductor elements 271, 272 are directly mounted on the first main surface 23u of the reinforcing member 23. A bonding material 275 such as an adhesive, a solder layer, or a metal paste may be provided between the plurality of semiconductor elements 271, 272 and the reinforcing member 23. In particular, when a direct electrical connection is made between the semiconductor substrate constituting the semiconductor element and the reinforcing member 23, it is desirable to use a solder layer and a metal paste as the bonding material 275. The first main surface 23u of the reinforcing member 23 may be plated with a Ni layer / Au layer, an Ag layer / Pd layer / Au layer, or the like from below.

  In such a circuit board 2, since the plurality of solid-state imaging devices are directly mounted on the first main surface 23u of the plate-like reinforcing member 23, the height of each of the plurality of solid-state imaging devices is reduced. The image pickup surfaces of the plurality of solid-state image pickup devices are less likely to shift, and are arranged more parallel to the first main surface 23u of the reinforcing member 23. Further, since the plurality of solid-state imaging devices are provided directly on the reinforcing member 23, the heat radiation effect of the reinforcing member 23 is further improved, and the temperature rise of the plurality of solid-state imaging devices is more reliably suppressed.

  Further, when the circuit board 2 is used, at least a part of each of the plurality of semiconductor elements 271 and 272 is housed in the recess 281 and the height of the bonding wire 265 is further reduced, so that the semiconductor module is made thinner. be able to.

  Further, in the circuit board 2, since the highly rigid reinforcing member 23 exists below the semiconductor elements 272 and 272, the semiconductor elements 271 and 272 are deformed due to an external force acting on the second substrate body 20 and a deformation caused by a temperature change. It can be protected reliably.

  (Third embodiment)

  FIG. 6 is a schematic sectional view illustrating the configuration of the circuit board according to the third embodiment. FIG. 6 corresponds to a sectional view taken along line BB in FIG.

  The circuit board 3 of the present embodiment is common to the first and second embodiments in having a first substrate main body 10 and a second substrate main body 20, and has a recess 281 for accommodating a plurality of semiconductor elements 271 and 272. This point is common to the second embodiment. However, the circuit board 3 differs from the first and second embodiments in that the concave portion 281 is divided into a plurality.

  In the circuit board 3, the concave portion 281 has a concave portion 281a and a concave portion 281b. In the circuit board 3, the plurality of semiconductor elements 271 and 272 are individually mounted in the plurality of recesses 281a and 281b, respectively.

  With such a circuit board, since the concave portion 281 is divided into a plurality of portions, the wiring layer 28 remains between the concave portions 281a and 281b, and the bonding pads 261 can be formed on the wiring layer 28. That is, the bonding pad 261 can be arranged between the plurality of semiconductor elements 271, 272. Thereby, the degree of freedom of arrangement of the bonding pads 261 is improved.

  (Fourth embodiment)

  FIG. 7 is a schematic sectional view illustrating the configuration of the circuit board according to the fourth embodiment. FIG. 7 corresponds to a cross-sectional view taken along line BB in FIG.

  The circuit board 4 is common to the circuit board 1 in that the reinforcing member 23 is housed in the housing portion 213. However, in the circuit board 4, the wirings 225 and 226 are provided on the main surfaces 23u and 23d of the reinforcing member 23. For example, the insulating layer 215 is provided on the first main surface 23u of the reinforcing member 23 in the housing portion 213, and the insulating layer 216 is provided on the second main surface 23d. Further, a wiring 225 is provided in the insulating layer 215, and a wiring 226 is provided in the insulating layer 216. The wiring 225 is electrically connected to the wiring 221 via, for example, a via, and the wiring 226 is electrically connected to the wiring 222 via, for example, a via.

  The configuration in which the wirings 225 and 226 are disposed on both the main surfaces 23u and 23d of the reinforcing member 23 may be combined with the circuit board 2 of the second embodiment and the circuit board 3 of the third embodiment.

  As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and it is needless to say that various modifications can be made. Each embodiment is not limited to an independent form, and can be combined as technically as possible.

  For example, in the above embodiment, the planar shape of each of the second substrate body 20 and the reinforcing member 23 is formed in a rectangular shape. However, the present invention is not limited to this. It may be formed.

  Further, although the control board 30 is provided on the second end 11b of the flexible wiring base 11, a contact component such as a connector may be provided instead of the control board 30.

1, 2, 3, 4 ... circuit board 10 ... first substrate body 11 ... flexible wiring base material (wiring base material)
110 resin core 111, 112 wiring layer 113 insulating layer 11a first end 11b second end 11u first main surface 11d second main surface 12 reinforcing part 20 second substrate body 211 212, 215, 216 ... Insulating layer 213 ... Housing part 221, 222, 225, 226 ... Wiring 223 ... Interlayer connection part 23 ... Reinforcement member 23u ... First main surface 23d ... Second main surface 231 ... Groove 232 ... Through hole 241 ... First insulating material 242... Second insulating material 243... Stacked parts 251, 252... Insulating layer 261. Reference numeral 30: control board 31: multilayer wiring section 40: element mounting section

Claims (9)

A wiring substrate,
The have a second main surface on the opposite side is buried in the opening formed in the wiring substrate is a first major surface and the first major surface, between the first main surface and the second main surface A plate-like reinforcing member having a groove formed therethrough, a wiring layer provided on the first main surface and the second main surface, the wiring layer including an insulating layer, and a plurality of semiconductor elements on the first main surface. circuit board having a directly or indirectly possess the mountable element mounting portion, the reinforcement portion in which the high thermal expansion coefficient smaller elastic modulus than that of the insulating layer the first insulating material to said grooved . The circuit board according to claim 1,
When projecting each of the reinforcing member and the element mounting portion in the thickness direction of the reinforcing portion,
The circuit board, wherein the element mounting portion is included in a region of the reinforcing member. The circuit board according to claim 1, wherein:
The reinforcing portion further includes a bonding pad electrically connected to each of the plurality of semiconductor elements,
The circuit board, wherein the bonding pad is arranged on the wiring layer on the first main surface. It is a circuit board according to any one of claims 1 to 3,
The wiring base has a portion extending from the opening,
The part is a flexible circuit board. A circuit board according to any one of claims 1 to 4,
The wiring layer has a concave portion exposing the first main surface of the reinforcing member,
A circuit board on which the plurality of semiconductor elements may be arranged in the recess. The circuit board according to claim 5, wherein
The circuit board may be divided into a plurality of recesses, and the plurality of semiconductor elements may be individually accommodated in the plurality of divided recesses. A circuit board according to any one of claims 1 to 6,
A circuit board having a lower elastic modulus than an insulating layer included in the wiring layer, and further comprising a second insulating material provided between the opening and the reinforcing member. A wiring substrate, the wiring is buried in the opening formed in the substrate have a second major surface opposite the first major surface and the first major surface, wherein said first major surface a second A plate-like reinforcing member having a groove formed therethrough between the main surface, a wiring layer provided on the first main surface and the second main surface, the wiring layer including an insulating layer ; a plurality of elements have a directly or indirectly mountable element mounting portion, the circuit having a reinforcement portion in which the thermal expansion coefficient than the insulating layer is smaller elastic modulus is high insulating material into the groove is provided Board and
A semiconductor module comprising: a plurality of semiconductor elements mounted on the element mounting portion. The semiconductor module according to claim 8, wherein:
The semiconductor module, wherein each of the plurality of semiconductor elements is a solid-state imaging device.

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