JP2006237230A - Compound wiring board structure and its production process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compound wiring board structure which can enhance yield by lowering failure rate. <P>SOLUTION: The compound wiring board structure 11 comprises a first substrate 51, a second substrate 31, and a function module 91. A semiconductor circuit element 21 is connected to an element mounting portion 56 set on the first major surface 52 side of the first substrate 51. The function module 91 is bonded to the first major surface 52 side of the first substrate 51, and the second substrate 31 is bonded to the second major surface 53 side of the first substrate 51. The conductor portion 57 of the first substrate 51, the conductor portion 35 of the second substrate 31, and the conductor portion 96 of the function module 91 are interconnected electrically. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a composite wiring board structure and a manufacturing method thereof.

In recent years, in the field of electrical products such as personal computers and digital home appliances, and in the field of automobiles, the miniaturization, high functionality, and high added value of products have been increasing. Accordingly, miniaturization and high density of the motherboard, which is an important electrical component in this type of product, are desired, and miniaturization of various components mounted on the motherboard is also desired. An example of such a component is a substrate for mounting an electronic component such as an IC chip (see, for example, Patent Document 1). Here, Patent Document 1 is a so-called rigid / flexible substrate in which a flexible substrate is attached to a rigid substrate having high mechanical strength via an adhesive. An IC chip is mounted on the flexible substrate side of the rigid flexible substrate.
Japanese Unexamined Patent Publication No. 2004-187202 (FIG. 4 etc.)

  By the way, when manufacturing the rigid / flexible substrate of the above-mentioned Patent Document 1, via holes are formed through the stacked body in the stacking direction in a step after the flexible substrate is stacked on the rigid substrate. The conductor portion was formed by filling the via hole with copper plating or conductive metal paste. In this case, since it is not possible to perform an electrical inspection for finding a wiring failure unless the flexible substrate is laminated on the rigid substrate, even if at least one of the rigid substrate and the flexible substrate is a defective product, It cannot be removed in advance. As a result, there is a high probability that the completed rigid / flexible substrate will be a defective product, leading to a decrease in yield.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a composite wiring board structure and a method for manufacturing the same that reduce the probability of being a defective product and lead to an improvement in yield.

  And as a means (means 1) for solving the above-mentioned problem, an element mounting portion having a first main surface and a second main surface, to which a semiconductor circuit element can be connected, is set on the first main surface side. The first substrate, the second substrate bonded to the second main surface side of the first substrate, and bonded to at least one of the first main surface and the second main surface of the first substrate A composite wiring board structure comprising: a conductor portion of the first substrate; a conductor portion of the second substrate; and a conductor portion of the functional module that are electrically connected to each other. is there.

  Therefore, in the case of this composite wiring board structure, the conductor portion of the first substrate, the conductor portion of the second substrate, and the conductor portion of the functional module are electrically connected to each other. For this reason, for example, a first substrate, a second substrate, and a functional module having different functions are prepared in advance, and then the second substrate and the functional module are joined to the first substrate, whereby a composite wiring board structure is obtained. The body can have multiple functions.

  In addition, since the composite wiring board structure of the present invention has a functional module in addition to the first board and the second board, it is more multifunctional than the prior art described in Patent Document 1 consisting of two kinds of boards. Can be achieved. Therefore, it becomes easy to realize one systemized composite wiring board structure (so-called system in package: SIP), and the added value is also increased.

  Furthermore, since the second substrate is bonded to the first substrate and the functional module is bonded to the first substrate, before the second substrate is bonded to the first substrate or before the functional module is bonded to the first substrate, Electrical inspection of the first substrate, the second substrate, and the functional module can be performed individually. For this reason, since a defective product can be found and removed in advance before joining, only the first board, the second board and the functional module that have passed the electrical inspection are joined to form a composite wiring board structure. can do. Therefore, the probability that the composite wiring board structure becomes a defective product is reduced, leading to an improvement in yield.

  The semiconductor circuit element to be mounted on the composite wiring board structure according to the means 1 includes a semiconductor integrated circuit element, a MEMS (Micro Electro Mechanical Systems) element manufactured by a semiconductor manufacturing process, and the like. Examples of the semiconductor integrated circuit element include a semiconductor integrated circuit chip (IC chip) made of silicon having a thermal expansion coefficient of about 2.6 ppm / ° C. The MEMS element refers to a fine circuit element manufactured by a micromachining technique based on a semiconductor IC manufacturing process, and is usually composed mainly of silicon. Furthermore, MEMS is a general term for a micro system in which micro-sized sensors, actuators, and control circuits manufactured by a micromachining technology based on an IC manufacturing process are integrated. The size and shape of the semiconductor circuit element are not particularly limited.

  The first substrate may have the same function as at least one of the second substrate and the functional module, or may have a function different from that of the second substrate and the functional module. The main function of the first substrate is to support the semiconductor circuit element. Other functions of the first substrate include a function of connecting the semiconductor circuit element and the second substrate, a function of connecting the semiconductor circuit element and the function module, and a function of connecting the second substrate and the function module. Can be mentioned.

  In the first substrate, an element mounting portion to which a semiconductor circuit element can be connected is set on the first main surface side. It is preferable that the element mounting portion is set in a region on the opposite side of the second substrate. In this way, even if the first substrate has low rigidity, for example, if the second substrate bonded to the second main surface side of the first substrate is highly rigid, connection reliability can be easily maintained. In addition, since the wiring length connecting the second substrate and the semiconductor circuit element (that is, the element mounting portion) is shortened, it is possible to increase the speed of the signal between the second substrate and the semiconductor circuit element. Furthermore, when the second substrate has a capacitor, the power supply can be stabilized by reducing the inductance between the capacitor and the semiconductor circuit element. Note that only one such element mounting portion may be set on the first substrate, but a plurality of such element mounting portions may be set.

  In addition, examples of the material for forming the first substrate include inorganic materials such as ceramics, metals, and semiconductors, and organic materials such as resins. In consideration of cost, workability, insulation, mechanical strength, and the like. It can select suitably from them. Preferable examples of the ceramic material include low-temperature fired materials such as alumina, glass ceramic, and crystallized glass, aluminum nitride, silicon carbide, and silicon nitride. Suitable examples of the metal material include copper, a copper alloy, and an iron nickel alloy. A preferred example of the semiconductor material is silicon. Preferred examples of the resin material include PI resin (polyimide resin), EP resin (epoxy resin), BT resin (bismaleimide-triazine resin), PPE resin (polyphenylene ether resin), and the like. In addition, composite materials of these resins and glass fibers (glass woven fabric or glass nonwoven fabric) or organic fibers such as polyamide fibers may be used. Alternatively, a resin-resin composite material obtained by impregnating a thermosetting resin such as an epoxy resin with a three-dimensional network fluorine-based resin base material such as continuous porous PTFE may be used. In particular, from the viewpoint of cost reduction or the like, it is preferable to select an organic material such as a resin material as a material for forming the first substrate. With such a wiring board, a fine wiring layer can be formed relatively easily and accurately, and an element mounting portion capable of connecting a semiconductor circuit element having a very large number of terminals can be easily formed. it can. That is, such a wiring board is suitable as a board for mounting a semiconductor circuit element.

  In addition, the material for forming the first substrate is preferably an organic material such as a resin material. In particular, the first substrate is preferably a flexible wiring substrate. In this way, since it can be formed relatively thin, the composite wiring board structure can be downsized in the thickness direction (Z direction). Further, when the second substrate is a ceramic substrate, it can be formed larger than that, so that another structure can be mounted on the projecting portion by projecting from the ceramic substrate. In addition, since it can be used in a state where a predetermined portion of the first substrate is bent, the composite wiring board structure can be downsized by bending the first substrate. Therefore, even when the space in which the composite wiring board structure is accommodated is narrow, there is a high possibility that it can be accommodated well by bending the first substrate.

  Furthermore, the first substrate has a plurality of conductor patterns fanning out around the element mounting portion as a center and a plurality of via conductors electrically connected to the plurality of conductor patterns as a conductor portion. A flexible wiring board is preferable. In this way, since the plurality of conductor patterns fan out around the element mounting portion as a center, the semiconductor circuit element and the second substrate (or functional module) are reliably electrically connected via the first substrate. Can be connected to. In addition, since the first substrate is a multilayer flexible wiring substrate, it can sufficiently cope with finer semiconductor circuit elements expected in the future. In addition, as compared with the case where the flexible wiring board is not multi-layered (only one layer is provided), it is possible to configure more circuits inside, and the added value can be increased.

  The second substrate may have the same function as at least one of the first substrate and the functional module, or may have a function different from that of the first substrate and the functional module. The second substrate may have a “function” that electrically assists the functions of the first substrate and the semiconductor circuit element. As a specific example in which the second substrate has a function of electrically assisting the function of the semiconductor circuit element, the second substrate is a “function as a passive component involved in improving the operability of the semiconductor circuit element. For example, having a “function” as a passive component for stabilizing a power supply to be supplied to the semiconductor circuit element. Specific examples thereof include that the second substrate itself is established as having such a passive component function (for example, a capacitor function).

  The second substrate is preferably provided with a passive component mounting portion capable of connecting passive components involved in improving the operability of the semiconductor circuit element. For example, a power supply to be supplied to the semiconductor circuit element is stabilized. It is preferable to have a passive component to make it. Specific examples of this type of passive component include a diode, a resistor, an inductor, a capacitor, and a coil. The passive component mounting part to which the passive components listed here can be connected may be set on the surface of the second substrate or may be set inside.

  The material for forming the second substrate is not particularly limited, and can be appropriately selected in consideration of cost, workability, insulation, mechanical strength, and the like. When the first substrate is the low-rigidity flexible wiring substrate, the second substrate is preferably a high-rigidity rigid substrate. In this way, the semiconductor circuit element is supported not only by the first substrate but also by the second substrate, so that the semiconductor circuit element is stably connected to the element mounting portion. Therefore, it becomes easy to maintain the connection reliability of the semiconductor circuit element. Examples of the rigid substrate include a ceramic substrate, a resin substrate, a metal substrate, and a Si substrate. In particular, the rigid substrate is preferably a ceramic substrate mainly composed of an inorganic material. This is because ceramic is excellent in rigidity, so that the mechanical strength of the composite wiring board structure can be increased. Moreover, since ceramic is excellent in heat dissipation, even when a heat generating component is mounted on the composite wiring board structure, the heat can be efficiently dissipated. Moreover, since ceramic materials generally have a lower coefficient of thermal expansion than metals and resins, they are suitable as materials for rigid substrates. Specific examples of the ceramic substrate include, but are not limited to, an alumina substrate, an aluminum nitride substrate, a beryllia substrate, a glass ceramic substrate, and a substrate made of a low-temperature fired material such as crystallized glass. The rigid substrate is preferably a ceramic wiring substrate provided with a wiring layer or the like. By doing so, it is possible to configure a circuit in the inside as compared with a simple substrate having no wiring layer, and the added value can be increased.

  The second substrate has a bonding surface bonded to the first substrate and a non-bonding surface positioned on the opposite side of the bonding surface, and a plurality of terminals included in the motherboard are provided on the non-bonding surface. It is preferable that a plurality of external connection terminals that can be connected are provided. The material for forming the mother board is not particularly limited, and can be appropriately selected in consideration of cost, workability, insulation, mechanical strength, and the like. Examples of the mother board include a resin one, a ceramic one, and a metal one. In particular, the mother board is preferably made of resin from the viewpoint of cost.

  The functional module may have the same function as at least one of the first substrate and the second substrate, or may have a function different from that of the first substrate and the second substrate. The functional module may be a module wiring board having a circuit configured to include a plurality of types of electronic components, and may include a functional member such as a MEMS. In this way, compared to a simple substrate having no wiring layer, it is possible to configure a circuit therein and increase the added value. Specific examples of the functional module include an RF module having a wireless communication function, a power supply module having a function of controlling a power supply voltage, and the like. Specific examples of the electronic components constituting the functional module include a chip transistor, a chip diode, a chip resistor, a chip capacitor, a chip coil, and a MEMS element. These electronic components may basically be active components or passive components, and are appropriately selected according to the contents of functions to be realized by the module.

  The second substrate and the functional module are preferably joined so as to avoid a bent portion (a planned bending portion) in the first substrate. If comprised in this way, even if it is a case where the 1st board | substrate is bent and used, the situation where a big deformation | transformation will arise in the joining location of a 2nd board | substrate and the joining location of a functional module can be avoided. It is possible to prevent a decrease in connection reliability at this point.

  Further, the second substrate is bonded to the second main surface side of the first substrate via a first adhesive layer, and the conductor portion of the first substrate is interposed via the conductor portion in the first adhesive layer. It is preferable that the conductor part of the said 2nd board | substrate is electrically connected. The reason is that if there is a conductor portion in the first adhesive layer, it becomes easy to reliably connect the conductor portion of the first substrate and the conductor portion of the second substrate through the conductor portion. Similarly, the functional module is bonded to at least one side of the first main surface and the second main surface of the first substrate via a second adhesive layer, and the conductor in the second adhesive layer It is preferable that the conductor part of the first substrate and the conductor part of the functional module are electrically connected via the part. The reason is that if there is a conductor portion in the second adhesive layer, the conductor portion of the first substrate and the conductor portion of the functional module can be reliably connected via the conductor portion.

  Suitable examples of the first adhesive layer and the second adhesive layer include an adhesive sheet formed using an insulating adhesive resin material. Moreover, as the insulating adhesive material in the adhesive sheet, for example, liquid crystal polymer, thermoplastic polyimide, polyetheretherketone, and the like are suitable. By using such a heat resistant material, it becomes easy to realize a composite wiring board structure excellent in connection reliability at a high temperature. In addition, it is preferable that a conductor part is what conducts the front and back of an adhesive sheet. The reason is that if there is a conductor portion in the adhesive sheet, the conductor portion of the first substrate and the conductor portion of the second substrate (or the conductor portion of the first substrate and the conductor portion of the functional module) are more reliably passed through the conductor portion. Because it becomes easy to connect to. Specifically, the adhesive sheet includes a sheet first main surface, a sheet second main surface, and a conductor provided in a via hole that communicates the sheet first main surface side and the sheet second main surface side. It is preferable to have a pillar.

  The conductor part of the first substrate, the conductor part of the second substrate, the conductor part of the functional module, the conductor part of the first adhesive layer, and the conductor part of the second adhesive layer are formed of a conductive metal, for example. Is done. Although it does not specifically limit as said conductive metal, For example, 1 type, or 2 or more types of metals selected from copper, gold | metal | money, silver, platinum, palladium, nickel, tin, lead, titanium, tungsten, molybdenum, tantalum, niobium etc. Can be mentioned. Examples of the conductive metal composed of two or more metals include solder that is an alloy of tin and lead. Lead-free solder (for example, Sn-Ag solder, Sn-Ag-Cu solder, Sn-Ag-Bi solder, Sn-Ag-Bi-Cu solder) as a conductive metal composed of two or more metals Of course, Sn—Zn solder, Sn—Zn—Bi solder, etc.) may be used.

  Further, as another means (means 2) for solving the above problems, there is an element mounting portion having a first main surface and a second main surface, and a semiconductor circuit element can be connected to the first main surface side. A first substrate set and a second substrate bonded to the second main surface side of the first substrate, and at least one of the first main surface and the second main surface of the first substrate There is a composite wiring board structure in which a functional module mounting portion is set on one side, and the conductor portion of the first substrate and the conductor portion of the second substrate are electrically connected to each other.

  Therefore, in the case of this composite wiring board structure, the conductor portion of the first substrate and the conductor portion of the second substrate are electrically connected to each other. For this reason, for example, a first substrate and a second substrate having different functions are prepared in advance, and then the second substrate is bonded to the first substrate, so that the composite wiring board structure has a plurality of functions. You can have it.

  Furthermore, since the second substrate is bonded to the first substrate, the electric inspection of the first substrate and the second substrate can be individually performed before the second substrate is bonded to the first substrate. For this reason, since a defective product can be found and removed in advance before bonding, it is possible to form a composite wiring board structure by bonding only the first substrate and the second substrate that have passed the electrical inspection. it can. Therefore, the probability that the composite wiring board structure becomes a defective product is reduced, leading to an improvement in yield.

  Further, in the composite wiring board structure according to the means 2, it is preferable that a functional module substrate main body that becomes a part of the functional module is bonded to the functional module mounting portion. In this way, since the composite wiring board structure has the functional module board main body in addition to the first board and the second board, it is possible to increase the number of functions as compared with the case where it is composed of two kinds of boards.

  As a preferable method (means 3) for relatively easily and reliably manufacturing the composite wiring board structure described in means 1, the first substrate, the second substrate, and the functional module are individually manufactured. The manufacturing process, the first substrate and the second substrate are joined, the first substrate and the functional module are joined, and at that time, the conductor portion of the first substrate and the conductor portion of the second substrate And a bonding step for electrically connecting the conductor portions of the functional module to each other.

  Therefore, according to this method of manufacturing a composite wiring board structure, the first substrate, the second substrate, and the functional module are joined before the first substrate and the second substrate are joined and before the first substrate and the functional module are joined. The electrical inspection can be performed individually. For this reason, since a defective product can be found and removed in advance before joining, only the first board, the second board and the functional module that have passed the electrical inspection are joined to form a composite wiring board structure. can do. Therefore, the probability that the composite wiring board structure becomes a defective product is reduced, leading to an improvement in yield.

  Hereinafter, a method for manufacturing the composite wiring board structure described in the means 3 will be described.

  First, an individual manufacturing process is performed to individually manufacture the first substrate, the second substrate, and the functional module.

  The production of the second substrate in the individual production process is performed according to a conventionally known technique. For example, when the second substrate is a ceramic substrate, a ceramic green sheet as a rigid substrate is prepared, and via holes penetrating both surfaces are formed at predetermined positions of the ceramic green sheet. Furthermore, each via hole is filled with a conductive paste containing metal to form a conductor portion, and if necessary, the conductive paste is also printed on the sheet surface. Then, by firing at a predetermined temperature, the ceramic and the metal are sintered to obtain a predetermined ceramic substrate. In the case of a ceramic multilayer substrate, for example, a plurality of ceramic green sheets filled and printed with a conductive paste are stacked and pressure-bonded, and then fired.

  The first substrate and the functional module in the individual manufacturing process are basically performed according to a conventionally known method. Specifically, for example, a copper-clad laminate having a copper foil on one side or both sides is used as a base material, and via holes penetrating both sides are formed. Further, after a conductor portion is formed in each via hole by a method such as filling with a conductive metal paste or copper plating, the copper foil on the surface is etched to pattern a wiring layer or the like.

  Preferably, the method further includes an individual inspection step of individually performing an electrical inspection of the first substrate, the second substrate, and the functional module before the bonding step. In this way, a defective product can be found before joining and removed in advance.

  Next, a joining process is performed. In this case, after the second substrate is bonded onto the first substrate, the functional module may be bonded onto the first substrate, or after the functional module is bonded onto the first substrate, the second substrate is bonded onto the first substrate. However, the second substrate and the functional module may be simultaneously bonded on the first substrate. If the bonding is performed at the same time, man-hours are reduced, and it becomes easier to improve production efficiency and reduce manufacturing costs.

  It is preferable to perform a predetermined positioning step in advance before the bonding step. That is, the conductor portion of the first substrate and the conductor portion of the second substrate are arranged in correspondence with each other, and the conductor portion of the first substrate and the conductor portion of the functional module are arranged in correspondence with each other.

  In the bonding step, a first adhesive layer is disposed and laminated as necessary at the interface between the first substrate and the second substrate. When the first adhesive layer is disposed, the conductor portion of the first substrate and the conductor portion of the second substrate are disposed via the conductor portion of the first adhesive layer. In this state, for example, a pressing force is applied in the stacking direction while heating. As a result, the first substrate and the second substrate are bonded. In the case where the first adhesive layer is not disposed, it is preferable that the conductor portion of the first substrate and the conductor portion of the second substrate are brought into pressure contact with each other by applying a pressing force in the stacking direction in the joining step. If it does in this way, reliable conduction | electrical_connection between the conductor part of a 1st board | substrate and the conductor part of a 2nd board | substrate can be aimed at. In addition, a second adhesive layer is disposed and laminated as necessary at the interface between the first substrate and the functional module. When the second adhesive layer is disposed, the conductor portion of the first substrate and the conductor portion of the functional module are disposed via the conductor portion of the second adhesive layer. In this state, for example, a pressing force is applied in the stacking direction while heating. As a result, the first substrate and the functional module are joined. In addition, when not arrange | positioning a 2nd contact bonding layer, it is preferable to press-contact the conductor part of the said 1st board | substrate and the conductor part of the said functional module by applying pressing force in the lamination direction in the said joining process. If it does in this way, reliable conduction | electrical_connection between the conductor part of a 1st board | substrate and the conductor part of a functional module can be aimed at. In addition, the heating temperature at this time depends on the types of materials of the first substrate, the second substrate, and the functional module, the types of the first adhesive layer and the second adhesive layer to be used, and the curing degrees of the first adhesive layer and the second adhesive layer. It is set appropriately according to the above.

  In addition, as another preferable method (means 4) for relatively easily and surely manufacturing the composite wiring board structure described in means 1, the first substrate, the second substrate, and the functional module may be used. An individual production step of individually producing a functional module substrate main body that is a part of the first and second substrates, bonding the first substrate and the functional module substrate main body, And a bonding step of electrically connecting the conductor portion of the first substrate, the conductor portion of the second substrate, and the conductor portion of the functional module substrate body to each other. There is a way.

  Therefore, according to the method for manufacturing the composite wiring board structure, the first board, the second board, and the second board are joined before the first board and the functional module board body are joined. The electrical inspection of the functional module substrate body can be performed individually. For this reason, since a defective product can be found and removed in advance before bonding, the composite wiring board structure is formed by bonding only the first board, the second board, and the functional module board body that have passed the electrical inspection. Can be configured. Therefore, the probability that the composite wiring board structure becomes a defective product is reduced, leading to an improvement in yield.

  Moreover, the method for manufacturing a composite wiring board structure according to the means 4 may further include an electronic component bonding step of bonding the electronic component to the functional module substrate body. In addition, although an electronic component joining process may be implemented before implementation of the said joining process, it is preferable to implement after implementation of the said joining process. If it does in this way, the pressing force applied when joining a 1st board | substrate and a functional module board | substrate body will not be added to an electronic component. Therefore, the occurrence of cracks in the electronic component can be reliably prevented.

  Hereinafter, an embodiment embodying the present invention will be described in detail with reference to FIGS. FIG. 1 is a schematic cross-sectional view showing a composite wiring board structure 11 according to the present embodiment including a flexible wiring board (first board) 51, a ceramic wiring board (second board, ceramic board) 31, a module wiring board 91, and the like. is there. FIG. 2 is an exploded cross-sectional view illustrating a configuration of a structure including the flexible wiring board 51 and the ceramic wiring board 31. FIG. 3 is an exploded cross-sectional view showing a configuration of a structure including the flexible wiring board 51 and the board body 95 (functional module board body). 4 to 6 are schematic cross-sectional views showing a state when the adhesive sheets 61 and 71 are produced. FIG. 7 is a schematic cross-sectional view showing a state when the flexible wiring board 51 and the ceramic wiring board 31 are joined to each other. FIG. 8 is a schematic cross-sectional view showing a state when the flexible wiring board 51 and the board body 95 are joined to each other.

  As shown in FIG. 1, the composite wiring board structure 11 of the present embodiment can be mounted on a mother board 81, and is a BGA (ball ball) composed of a flexible wiring board 51, a ceramic wiring board 31, and a module wiring board 91. Grid array). The form of the composite wiring board structure 11 is not limited to BGA alone, and may be, for example, LGA (land grid array), PGA (pin grid array), or the like. The motherboard 81 in the present embodiment is a so-called glass epoxy substrate made of epoxy resin and glass fiber, and has a thermal expansion coefficient of about 16 ppm / ° C. in the plane direction. Here, “thermal expansion coefficient” generally refers to a value measured by TMA (thermomechanical analyzer) between room temperature and glass transition temperature (Tg). “TMA” refers to thermomechanical analysis, such as that defined in JPCA-BU01.

  The ceramic wiring substrate 31 shown in FIGS. 1 and 2 has an upper surface 32 (joint surface) and a lower surface 33 (non-joint surface) located on the opposite side of the upper surface 32. The ceramic wiring board 31 has a structure in which a plurality of ceramic layers 30 and a plurality of wiring layers (not shown) are alternately stacked. In addition, a plurality of via holes 34 penetrating the upper surface 32 and the lower surface 33 are formed in the ceramic wiring substrate 31 in a lattice shape. In the via hole 34, a via conductor 35 (conductor portion) mainly made of tungsten is provided. An upper terminal electrode 36 made of tungsten is provided on the upper end surface of each via conductor 35. On the other hand, a plurality of board-side solder bumps 49 (external connection terminals) for electrical connection with the plurality of terminals 82 of the mother board 81 are provided in a grid pattern on the lower end surface of each via conductor 35. . The board-side solder bumps 49 are made of tin-lead solder having a composition of 90Pb / 10Sn. In the present embodiment, the ceramic wiring substrate 31 is a substrate formed of an alumina sintered body obtained by sintering alumina (inorganic material). The thermal expansion coefficient in the plane direction of the ceramic wiring substrate 31 is about 7.6 ppm / ° C., and the Young's modulus is about 310 GPa. Therefore, the ceramic wiring board 31 of this embodiment has extremely high rigidity.

  The ceramic wiring substrate 31 of the present embodiment is formed with a substantially rectangular recess 130 (passive component mounting portion) that opens at the lower surface 33. A plate-like capacitor 131 (passive component) is disposed on the back side in the recess 130. The capacitor 131 is fixed in the recess 130 with an adhesive 133. The via conductor 134 of the capacitor 131 is electrically connected to the power supply via conductor 135 in the ceramic wiring substrate 31. The capacitor 131 has a function of stabilizing the power to be supplied to the IC chip 21 by removing noise. A plate-shaped memory IC 132 is fixed by an adhesive 133 near the opening of the recess 130. A connection terminal (not shown) of the memory IC 132 is electrically connected to a via conductor in the ceramic wiring substrate 31. In this way, the wiring length connecting the memory IC 132 and the IC chip 21 mounted on the upper surface of the composite wiring board structure 11 is shortened, which is suitable for high-speed data transmission.

  As shown in FIGS. 1 and 2, the flexible wiring substrate 51 is a multilayer flexible wiring substrate made of a resin substrate formed mainly of heat-resistant polyimide (organic material) having a thickness of about 20 μm. In this embodiment, the thermal expansion coefficient in the plane direction of the resin substrate is about 17 ppm / ° C., and the Young's modulus is about 6.5 GPa.

  The flexible wiring board 51 has an upper surface 52 (first main surface) and a lower surface 53 (second main surface). The flexible wiring substrate 51 is provided with a plurality of via conductors 57 (conductor portions) that penetrate the upper surface 52 and the lower surface 53. The upper surface side wiring layer 54 is electrically connected to the upper end surface of each via conductor 57, and the lower surface side wiring layer 55 is electrically connected to the lower end surface of each via conductor 57. Although not shown for convenience, the upper surface 52 side and the lower surface 53 side of the flexible wiring substrate 51 are covered with a coverlay. The flexible wiring board 51 is bonded to the upper surface 32 side of the ceramic wiring board 31 via an adhesive sheet 61 (first adhesive layer).

  The adhesive sheet 61 is formed using a heat-resistant thermoplastic resin (PEEK: polyetheretherketone in this embodiment) as an insulating base material. The sheet main body 63 constituting the adhesive sheet 61 has an upper surface 64 (sheet first main surface) and a lower surface 65 (sheet second main surface). The adhesive sheet 61 has a plurality of via holes 66 (see FIG. 5) communicating with the upper surface 64 and the lower surface 65 in a lattice shape. And in this via hole 66, the conductor pillar 62 (conductor part) formed by the filling of the electrically conductive paste containing the copper powder which coat | covered silver on the surface is provided. As shown in FIG. 1, the upper end surface of each conductor column 62 is electrically connected to the lower surface side wiring layer 55 of the flexible wiring substrate 51, and the lower end surface of each conductor column 62 is the upper terminal electrode of the ceramic wiring substrate 31. 36 is electrically connected. As a result, each via conductor 57 is electrically connected to the via conductor 35 of the ceramic wiring substrate 31.

  Further, a plurality of flip chip connection pads which are a part of the upper surface side wiring layer 54 are arranged in a predetermined region on the upper surface 52 side of the flexible wiring substrate 51 (specifically, a region opposite to the ceramic wiring substrate 31). The element mounting portion 56 is set. An IC chip 21 (semiconductor circuit element) having a function as an MPU is flip-chip mounted on such an element mounting portion 56. The IC chip 21 of the present embodiment is a rectangular flat plate having a length of 12.0 mm, a width of 10.0 mm, and a thickness of 0.7 mm, and is made of silicon having a thermal expansion coefficient of about 2.6 ppm / ° C. Circuit elements (not shown) are formed on the lower surface layer of the IC chip 21. A plurality of bump-shaped surface connection terminals 22 are provided in a lattice pattern on the lower surface side of the IC chip 21. Each surface connection terminal 22 is electrically connected to the upper surface side wiring layer 54 (that is, flip chip connection pad) of the flexible wiring substrate 51. Accordingly, each surface connection terminal 22 is connected to the upper terminal electrode 36 on the ceramic wiring substrate 31 side via the adhesive sheet 61. In the flexible wiring board 51, a plurality of fine upper surface side wiring layers 54 (conductor patterns) fanned out around the element mounting portion 56 are formed in a pattern. In addition, an electronic component such as a memory may be further mounted on the element mounting portion 56.

  As shown in FIGS. 1 and 3, the flexible wiring board 51 has a portion (a protruding portion 58) that protrudes in the planar direction of the ceramic wiring substrate 31. A functional module mounting portion 59 in which a part of the upper surface side wiring layer 54 is arranged is set in a predetermined region on the upper surface 52 side of the overhang portion 58, and a module wiring board 91 is set in the functional module mounting portion 59. Are joined. In the present embodiment, the module wiring board 91 is established as a power supply module (functional module) having a function of controlling the power supply voltage. This power supply module is composed of a circuit including a plurality of types of electronic components 92. More specifically, the module wiring board 91 has a board body 95 that becomes a part of the module wiring board 91, and the board body 95 has an upper surface 93 and a lower surface 94. In the present embodiment, the substrate body 95 is a resin substrate made of an epoxy resin. A plurality of via holes (through holes) extending in the thickness direction of the module wiring substrate 91 are formed in the substrate body 95 in a lattice shape, and conductor columns 96 (conductor portions) made of copper plating are formed in the via holes. Is provided. An upper surface side pad 97 is disposed at a position where the upper end surface of each conductor pillar 96 exists on the upper surface 93. Each upper surface side pad 97 is connected to a bump-shaped surface connection terminal 98 provided on the electronic component 92 side. The electronic component 92 is a component such as a chip transistor or a chip resistor. On the other hand, a lower surface side pad 99 is disposed at a position where the lower end surface of each conductor pillar 96 is present on the lower surface 94.

  The module wiring board 91 is bonded to the upper surface 52 side of the flexible wiring board 51 through an adhesive sheet 71 (second adhesive layer). The adhesive sheet 71 is formed of the same material as the adhesive sheet 61. The sheet main body 73 constituting the adhesive sheet 71 has an upper surface 74 (sheet first main surface) and a lower surface 75 (sheet second main surface). The adhesive sheet 71 has a plurality of via holes 76 (see FIG. 5) communicating with the upper surface 74 and the lower surface 75 in a lattice shape. A conductor column 72 (conductor portion) made of the same material as that of the conductor column 62 is provided in the via hole 76. As shown in FIG. 1, the lower end surface of each conductor column 72 is electrically connected to the upper surface side wiring layer 54 of the flexible wiring substrate 51.

  As a result, current flows through a path (or a path opposite to this) of the upper surface side pad 97 to the conductor column 96 to the lower surface side pad 99 to the conductor column 72. Therefore, in the composite wiring board structure 11 having such a structure, the flexible wiring board 51 side and the electronic component 92 side are electrically connected via the conductor pillar 96 of the module wiring board 91. Therefore, signal input / output is performed between the flexible wiring board 51 and the electronic component 92 via the module wiring board 91.

  Therefore, in the composite wiring board structure 11 having such a structure, the via conductor 57 of the flexible wiring board 51 is connected to the ceramic wiring board via the lower surface side wiring layer 55, the conductor pillar 62 of the adhesive sheet 61 and the upper terminal electrode 36. 31 via conductors 35 are electrically connected. When the IC chip 21 is mounted on the element mounting portion 56, the surface connection terminal 22 of the IC chip 21 is connected to the via conductor 57 of the flexible wiring board 51 via the upper surface side wiring layer 54 (flip chip connection pad). Is electrically connected. Therefore, input / output of signals is performed between the ceramic wiring substrate 31 and the IC chip 21 and power for operating the IC chip 21 as an MPU is supplied.

  Next, a procedure for manufacturing the composite wiring board structure 11 will be described.

  First, an individual manufacturing process is performed to individually manufacture the flexible wiring board 51, the ceramic wiring board 31, and the module wiring board 91 (board body 95). Fabrication of the flexible wiring board 51 in the individual fabrication process is performed by a conventionally known method. That is, a drilling process is performed on the copper-clad laminate using a mechanical drill, a YAG laser, or a carbon dioxide gas laser, and via holes (not shown) penetrating the copper-clad laminate are formed in advance at predetermined positions. And the via conductor 57 is formed in a via hole by performing electroless copper plating and electrolytic copper plating according to a conventionally known method. Further, the upper surface side wiring layer 54 and the lower surface side wiring layer 55 are formed by etching both surfaces of the copper clad laminate. As a result, the flexible wiring board 51 is obtained.

  In addition, the ceramic wiring substrate 31 in the individual manufacturing process is basically manufactured by a conventionally known method. For example, a plurality of alumina green sheets are produced by a known ceramic green sheet forming technique. And the via hole which penetrates both front and back surfaces is formed by punching etc. in the predetermined position of each green sheet. Further, a through-hole that will later become a recess 130 is formed at a predetermined position of each green sheet by punching or the like. That is, the formation of the through hole is not performed on the sintered ceramic layer 30 but on the soft green sheet before sintering, so that the recess 130 can be easily formed. Furthermore, a tungsten paste is filled into the via hole of each green sheet to form a paste filling layer that will later become the via conductor 35. Then, after laminating and pressure-bonding these green sheets, firing (simultaneous firing) is performed at a predetermined temperature in a reducing atmosphere to sinter alumina and tungsten paste. As a result, a laminate of a plurality of ceramic layers 30 having via conductors 35 and recesses 130 is produced. Next, after mounting the capacitor 131 on the back side in the recess 130, the memory IC 132 is mounted in the vicinity of the opening of the recess 130. Further, the capacitor 133 is fixed by filling the gap 133 between the recess 130 and the capacitor 131, and the memory 133 is filled by filling the gap 133 between the recess 130 and the memory IC 132. The memory IC 132 may be attached after the composite wiring board structure 11 is completed. As a result, the ceramic wiring board 31 shown in FIG. 2 is completed.

  Furthermore, the module wiring substrate 91 (substrate body 95) in the individual manufacturing process is basically manufactured by a conventionally known method. That is, drilling is performed on the copper clad laminate using a mechanical drill, and via holes (not shown) penetrating the copper clad laminate are formed in advance at predetermined positions. In addition, you may form a via hole by performing a laser drilling process with respect to a copper clad laminated board using a YAG laser or a carbon dioxide gas laser. Then, electroless copper plating and electrolytic copper plating are performed according to a conventionally known method to form the conductive pillar 96 in the via hole. Further, the copper foil on both sides of the copper clad laminate is etched to form the upper surface side pad 97 and the lower surface side pad 99 by, for example, a subtractive method. Specifically, after the electroless copper plating, electrolytic copper plating is performed using the electroless copper plating layer as a common electrode. Further, the dry film is laminated, and the dry film is exposed and developed to form a dry film in a predetermined pattern. In this state, unnecessary electrolytic copper plating layer, electroless copper plating layer and copper foil are removed by etching. Thereafter, the substrate main body 95 is obtained by peeling the dry film. The upper surface side pad 97 and the lower surface side pad 99 may be formed by a semi-additive method. Specifically, after electroless copper plating, exposure and development are performed to form a predetermined pattern of plating resist. In this state, after electrolytic copper plating is performed using the electroless copper plating layer as a common electrode, the resist is first dissolved and removed, and unnecessary electroless copper plating layer and copper foil are removed by etching. As a result, a substrate body 95 is obtained.

Moreover, the adhesive sheet 61 (or adhesive sheet 71) is produced in the following manner (adhesive sheet production process). Specifically, the adhesive organic material sheet 60 (see FIG. 4) cut to a predetermined size is punched using a mechanical drill, YAG laser, CO ₂ laser, punching device, etc. A via hole 66 (or via hole 76) penetrating the conductive organic material sheet 60 is previously formed at a predetermined position (see FIG. 5). In addition, the punch pin of the punching apparatus of this embodiment has a diameter of 120 μm. The via hole 66 (or the via hole 76) has an upper opening with a diameter of about 117 μm and a lower opening with a diameter of about 113 μm. Next, the conductive paste is filled into the via hole 66 (or via hole 76) by a conventionally known printing method to form the conductor column 62 (or conductor column 72). Specifically, the adhesive organic material sheet 60 is placed on a support base (not shown). Next, a printing mask having an opening at a position corresponding to the via hole 66 (or via hole 76) is used, the printing pressure is set to 2 kgf / cm ² , the printing speed is set to 50 mm / sec, and the surface is coated with silver. The conductive paste containing the copper powder is printed to form a paste filling layer. And after removing from a printing apparatus, a conductive paste is heated and a solvent etc. are evaporated and it solidifies. Next, temporary curing is performed by heating at a temperature of about 100 ° C. for about 30 minutes. Thereby, the conductor column 62 (or the conductor column 72) made of the conductive paste is slightly cured, and the adhesive sheet 61 (adhesive sheet 71) is completed. As a result, the conductor pillar 62 (or conductor pillar 72) is formed in the via hole 66 (or via hole 76). At this time, the tip end portion of the conductor column 62 (conductor column 72) protrudes from the upper surface of the adhesive organic material sheet 60 by about 20 μm (see FIG. 6). With such a structure, when the ceramic wiring board 31 is joined to the flexible wiring board 51, the tip end portion of the conductor pillar 62 and the lower surface side wiring layer 55 of the flexible wiring board 51 are pressed into contact with the flexible wiring board 51. When the substrate body 95 is joined, the tip end portion of the conductor column 72 and the lower surface side pad 99 of the substrate body 95 are pressed against each other. Therefore, for example, compared with the case where the tip portion is flat, the bonding strength with the conductor portion of the other substrate is increased, and the connection reliability is easily improved.

  Next, an electrical inspection process (individual inspection process) is performed, and electrical inspections of the completed flexible wiring board 51, ceramic wiring board 31, and module wiring board 91 are individually performed. As an electrical test in this embodiment, a general in-circuit test is performed using an in-circuit tester. Further, the visual inspection of the completed flexible wiring board 51, ceramic wiring board 31, and module wiring board 91 may be individually performed at this time. At this time, if a defective product is found, the defective product is removed in advance. And the process after a positioning process (a 1st positioning process or a 2nd positioning process) is performed only using the flexible wiring board 51, the ceramic wiring board 31, and the module wiring board 91 which passed the electrical inspection and the external appearance inspection. Therefore, the probability that the composite wiring board structure 11 becomes a defective product is reduced, leading to an improvement in yield.

  In the first positioning step, first, the flexible wiring board 51 is placed on the flat lower jig 101. In this case, a plurality of positioning pins 105 projecting from the lower jig 101 are inserted into the outer peripheral portion of the flexible wiring board 51. Thereby, the position shift to the plane direction of the flexible wiring board 51 is prevented. Next, the adhesive sheet 61 and the ceramic wiring board 31 are placed in order on the flexible wiring board 51. Then, the spacer 102 is placed on the lower jig 101. The plate thickness of the spacer 102 is substantially equal to the height of the laminated portion composed of the adhesive sheet 61 and the ceramic wiring substrate 31. A plurality of positioning pins 105 are inserted through the spacer 102. For this reason, the position shift to the plane direction of the adhesive sheet 61 and the ceramic wiring board 31 is prevented. Thereafter, a flat upper jig 104 is placed on the ceramic wiring substrate 31 and the spacer 102 (see FIG. 7). The upper jig 104 has a structure in which a cushion material 103 is attached to the lower surface side of the upper jig 104. In addition, it is also possible to perform positioning using what is called a die mounter apparatus which has an image recognition apparatus which detects the position of a board | substrate etc. instead of performing positioning using the above jig | tools.

  Next, the first joining step (joining step) is performed in the following manner. Specifically, in this embodiment, a pressing force (4 MPa) is applied in the laminating direction while heating to a temperature of 260 ° C. or higher under a vacuum of 20 Torr (≈2666 Pa) or less (vacuum hot press). Accordingly, the ceramic wiring board 31 is pressed toward the flexible wiring board 51 and the plasticity of the adhesive sheet 61 is increased by heat. And the ceramic wiring board 31 is joined to the lower surface 53 side of the flexible wiring board 51 through the adhesive sheet 61 in such a state. At this time, the via conductor 57 of the flexible wiring board 51 and the via conductor 35 of the ceramic wiring board 31 are electrically connected to each other via the conductor column 62 of the adhesive sheet 61. That is, since the bonding of the ceramic wiring substrate 31 to the flexible wiring substrate 51 is performed in a vacuum atmosphere, generation of voids due to air entrainment can be effectively suppressed.

  Next, a 2nd positioning process and a 2nd joining process (joining process) are implemented in the following ways. In addition, you may perform a 2nd positioning process and a 2nd joining process before a 1st positioning process and a 1st joining process. Moreover, if it is performed simultaneously with the first positioning step and the first joining step, the number of steps can be reduced and the cost can be reliably reduced.

  In the second positioning step, first, the flexible wiring board 51 is placed on the flat lower jig 151. In this case, a plurality of positioning pins 155 protruding from the lower jig 151 are inserted into the outer peripheral portion of the flexible wiring board 51. Thereby, the position shift to the plane direction of the flexible wiring board 51 is prevented. Next, the adhesive sheet 71 and the substrate body 95 are placed in order on the flexible wiring board 51. Then, the spacer 152 is placed on the lower jig 151. Note that the plate thickness of the spacer 152 is substantially equal to the height of the laminated portion including the adhesive sheet 71 and the substrate body 95. A plurality of positioning pins 155 are inserted through the spacer 152. For this reason, displacement of the adhesive sheet 71 and the substrate body 95 in the planar direction is prevented. Thereafter, a flat upper jig 154 is placed on the substrate body 95 and the spacer 152 (see FIG. 8).

  Next, a second joining step is performed. Specifically, in this embodiment, a pressing force (4 MPa) is applied in the laminating direction while heating to a temperature of 260 ° C. or higher under a vacuum of 20 Torr (≈2666 Pa) or less (vacuum hot press). As a result, the substrate body 95 is pressed toward the flexible wiring substrate 51 and the plasticity of the adhesive sheet 71 is increased by heat. Then, the substrate body 95 is bonded to the upper surface 52 side of the flexible wiring substrate 51 through the adhesive sheet 71 in such a state. At this time, the conductor column 96 of the substrate body 95 and the via conductor 35 of the ceramic wiring substrate 31 are electrically connected to each other via the conductor column 72 of the adhesive sheet 71. That is, since the bonding of the substrate body 95 to the flexible wiring substrate 51 is performed in a vacuum atmosphere, generation of voids due to air entrainment can be effectively suppressed.

  The upper jig 154 has a structure in which a cushion material 153 is attached to the lower surface side of the same jig 154. Therefore, the upper surface side pad 97 protruding from the upper surface 93 of the substrate body 95 comes into contact with the cushion material 153 which is an elastic body. At this time, the cushion material 153 is elastically deformed to follow the uneven shape on the substrate body 95 side. Thereby, a pressing force can be applied evenly to the substrate body 95.

  Next, solder paste printing is performed on the lower surface 33 of the ceramic wiring substrate 31 to form substrate-side solder bumps 49. In this way, the board-side solder bumps 49 do not have to be in the way when the first bonding step is performed. Also, when the substrate-side solder bump formation is performed after the first bonding step, the substrate-side solder bump 49 encounters a high temperature of 260 ° C. or higher, unlike the case where the substrate-side solder bump formation is performed before the first bonding step. It becomes difficult. Therefore, it is not always necessary to select a high melting point solder, and the degree of freedom in selecting a solder material is increased.

  Of course, the substrate-side solder bumps 49 may be formed at the same time when the step of manufacturing the ceramic wiring substrate 31 is performed, and then the first bonding step may be performed. In this way, when the ceramic wiring board 31 is inspected in the electrical inspection process, the board-side solder bumps 49 can be inspected, so that the composite wiring board structure is in a state where the board-side solder bumps 49 are defective. 11 can be prevented from being manufactured.

  In addition, a plurality of electronic components 92 are placed on the upper surface 93 side of the substrate body 95. At this time, the surface connection terminal 98 on the electronic component 92 side and the upper surface side pad 97 on the substrate body 95 side are aligned. And by heating and reflowing each surface connection terminal 98, the surface connection terminal 98 and the upper surface side pad 97 are joined (electronic component joining process). As a result, the composite wiring board structure 11 shown in FIG. 1 is completed.

  Thereafter, the IC chip 21 is mounted on the element mounting portion 56 of the flexible wiring board 51. At this time, the surface connection terminals 22 on the IC chip 21 side and the upper surface side wiring layer 54 on the flexible wiring board 51 side are aligned. And by heating and reflowing each surface connection terminal 22, the surface connection terminal 22 and the upper surface side wiring layer 54 are joined. At this stage, a composite wiring board structure 11 (so-called system in package: SIP) in which a plurality of functions are integrated and systematized is completed.

  Further, the board-side solder bumps 49 on the ceramic wiring board 31 side and the terminals 82 on the mother board 81 side are aligned, and the composite wiring board structure 11 is placed on the mother board 81. The substrate-side solder bumps 49 and the terminals 82 are joined by heating and reflowing the substrate-side solder bumps 49. Thereby, the composite wiring board structure 11 is mounted on the mother board 81. The IC chip 21 may be mounted after the composite wiring board structure 11 is mounted on the mother board 81.

  Therefore, according to the present embodiment, the following effects can be obtained.

  (1) According to the method for manufacturing the composite wiring board structure 11 of the present embodiment, before the ceramic wiring board 31 is joined to the flexible wiring board 51 or before the board body 95 is joined to the flexible wiring board 51, Electrical inspection of the wiring board 51, the ceramic wiring board 31, and the board body 95 can be performed individually. Therefore, since a defective product can be found and removed in advance before bonding, only the flexible wiring board 51, the ceramic wiring board 31 and the board main body 95 that have passed the electrical inspection are joined to form a composite wiring board structure. 11 can be configured.

  It is also conceivable that the module wiring board 91 is configured by mounting the electronic component 92 on the upper surface side pad 97 of the board body 95 and then the module wiring board 91 is bonded to the flexible wiring board 51. In this case, before the ceramic wiring board 31 is joined to the flexible wiring board 51 or before the module wiring board 91 is joined to the flexible wiring board 51, the electrical inspection of the flexible wiring board 51, the ceramic wiring board 31 and the module wiring board 91 is performed. Can be done individually. Therefore, since a defective product can be found and removed in advance before bonding, only the flexible wiring board 51, the ceramic wiring board 31 and the module wiring board 91 that have passed the electrical inspection are joined to form a composite wiring board structure. The body 11 can be configured.

  Therefore, the probability that the composite wiring board structure 11 becomes a defective product is reduced, and it is easy to achieve an improvement in yield. As a result, the manufacturing cost of the composite wiring board structure 11 can be reduced.

  (2) In the composite wiring board structure 11 of this embodiment, the via conductor 57 of the flexible wiring board 51, the via conductor 35 of the ceramic wiring board 31, and the conductor pillar 96 of the module wiring board 91 are electrically connected to each other. . For this reason, for example, the flexible wiring board 51, the ceramic wiring board 31, and the module wiring board 91 having different functions are prepared in advance, and then the ceramic wiring board 31 and the module wiring board 91 are joined to the flexible wiring board 51. By doing so, the composite wiring board structure 11 having a plurality of functions can be realized.

  Moreover, since the composite wiring board structure 11 includes the module wiring board 91 in addition to the flexible wiring board 51 and the ceramic wiring board 31, compared to the rigid / flexible board described in Patent Document 1 including two types of boards, Multiple functions can be achieved. Therefore, one systemized composite wiring board structure 11 (so-called system in package: SIP) can be easily realized, and the added value is also increased.

  (3) In the manufacturing method of the present embodiment, since the first bonding step is performed before the IC chip 21 is mounted on the element mounting portion 56 of the flexible wiring board 51, the load of the upper jig 104 is IC It does not join the chip 21. Therefore, the occurrence of cracks in the IC chip 21 can be reliably prevented. In the present embodiment, since the second bonding step is performed before the electronic component 92 is mounted on the upper surface side pad 97 of the substrate body 95, the load of the upper jig 154 is applied to the electronic component 92. There is no. Therefore, the occurrence of cracks in the electronic component 92 can be reliably prevented.

  In addition, you may change embodiment of this invention as follows.

  In the above embodiment, the module wiring board 91 is bonded to the upper surface 52 side of the flexible wiring board 51, but may be bonded to the lower surface 53 side of the flexible wiring board 51.

  In the above embodiment, the flexible wiring board 51 may be used in a state where a predetermined portion (the protruding portion 58) is bent upward or downward. Further, as shown in FIG. 9, the ceramic wiring board 31 and the module wiring board 91 may be joined so as to avoid a bent portion of the flexible wiring board 51. In this way, it is possible to avoid a situation in which a large deformation occurs at the joint location of the ceramic wiring board 31 or the joint location of the module wiring board 91, and it is possible to prevent a decrease in connection reliability at these locations.

  Further, as shown in FIG. 9, the flexible wiring board 51 is bent downward, and the joint portion of the module wiring board 91 in the flexible wiring board 51 is brought to the lower surface 33 side of the ceramic wiring board 31 through the adhesive layer 141. It may be glued. In this way, the flexible wiring board 51 can be held in a bent state. Instead of the adhesive layer 141, an adhesive sheet having the same configuration as that of the adhesive sheet 61 may be arranged so that the flexible wiring board 51 and the ceramic wiring board 31 are electrically connected via the adhesive sheet. In this way, a more complicated circuit can be formed in the composite wiring board structure 11.

  In the above embodiment, the flexible wiring board 51 may be a multilayer type multilayer flexible wiring board. That is, the flexible wiring substrate 51 may be configured by laminating a plurality of resin substrates via an adhesive layer.

  In the above embodiment, a structure different from the module wiring board 91 may be joined to the overhanging portion 58 of the flexible wiring board 51. For example, an electronic component such as a chip capacitor may be mounted on the upper surface side wiring layer 54 formed on the upper surface 52 of the flexible wiring substrate 51.

  In the above embodiment, the flexible wiring board 51 and the ceramic wiring board 31 are joined via the adhesive sheet 61, and the flexible wiring board 51 and the module wiring board 91 (board body 95) are joined via the adhesive sheet 71. It was. However, by using an anisotropic conductive adhesive instead of the adhesive sheets 61 and 71, the flexible wiring board 51 and the ceramic wiring board 31 may be joined, and the flexible wiring board 51 and the board body 95 may be joined. .

  Next, the technical ideas grasped by the embodiment described above are listed below.

  (1) A first substrate having a first main surface and a second main surface, wherein an element mounting portion to which a semiconductor circuit element can be connected is set on the first main surface side, and the second of the first substrate A second substrate bonded to the main surface side; and a functional module bonded to at least one of the first main surface and the second main surface of the first substrate, the conductor of the first substrate The conductive portion of the second substrate and the conductive portion of the functional module are electrically connected to each other, and the element mounting portion is set in a region opposite to the second substrate. Composite wiring board structure.

  (2) a first substrate having a first main surface and a second main surface, wherein an element mounting portion to which a semiconductor circuit element can be connected is set on the first main surface side, and the second of the first substrate A second substrate bonded to the main surface side via a first adhesive layer, and a second substrate bonded to at least one of the first main surface and the second main surface of the first substrate A conductive part of the first substrate, a conductive part of the second substrate, and a conductive part of the functional module are connected to each other, and the first adhesive layer and the second adhesive layer are A composite wiring board structure characterized in that both are adhesive sheets having a heat-resistant resin as an insulating base material.

  (3) The adhesive sheet includes a sheet first main surface, a sheet second main surface, and a conductor column provided in a via hole that communicates the sheet first main surface side and the sheet second main surface side. The composite wiring board structure according to (2) above, characterized by comprising:

  (4) A first substrate having a first main surface and a second main surface, wherein an element mounting portion to which a semiconductor circuit element can be connected is set on the first main surface side, and the second main surface of the first substrate An individual manufacturing step of individually manufacturing a functional module bonded to at least one of the second main surface and the second main surface of the first substrate bonded to the surface side; 1 substrate and the 2nd substrate are joined, and the 1st substrate and the functional module are joined, and at that time, the conductor part of the 1st substrate, the conductor part of the 2nd substrate, and the conductor of the functional module A bonding step of electrically connecting parts to each other, and prior to performing the bonding step, the conductor portion of the first substrate and the conductor portion of the second substrate are arranged in correspondence with each other, and the conductor of the first substrate Position in which the portion and the conductor portion of the functional module are arranged corresponding to each other Method for manufacturing a composite wiring board structure, characterized in that it comprises a fit process.

  (5) In the joining step, by applying a pressing force in the joining direction, the conductor portion of the first substrate and the conductor portion of the second substrate are brought into pressure contact, and the conductor portion of the first substrate and the functional module The method for producing a composite wiring board structure according to (4), wherein the conductor part is pressed into contact with the conductor part.

1 is a schematic cross-sectional view showing a composite wiring board structure including a flexible wiring board (first board), a ceramic wiring board (second board), a module wiring board (functional module), and the like in the present embodiment. The exploded sectional view showing the composition of the structure which consists of a flexible wiring board and a ceramic wiring board. The exploded sectional view showing composition of a structure which consists of a flexible wiring board and a module wiring board. The schematic sectional drawing which shows an adhesive organic material sheet in the preparation process of an adhesive sheet. The schematic sectional drawing which shows the process of forming a via hole in an adhesive organic material sheet in the preparation process of an adhesive sheet. The schematic sectional drawing which shows the process of forming a conductor pillar in a via hole in the preparation process of an adhesive sheet. The schematic sectional drawing which shows a mode when a flexible wiring board and a ceramic wiring board are mutually joined in the manufacture process of a composite wiring board structure. The schematic sectional drawing which shows a mode when a flexible wiring board and a module wiring board are joined together in the manufacture process of a composite wiring board structure. The schematic sectional drawing which shows the composite wiring board structure in other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Composite wiring board structure 21 ... IC chip 31 as a semiconductor circuit element ... Ceramic wiring board 32 as a second substrate and a ceramic substrate ... Upper surface 33 as a bonding surface ... Lower surface 35 as a non-bonding surface ... Via conductor 49 as a conductor portion ... Substrate-side solder bump 51 as an external connection terminal ... Flexible wiring substrate 52 as a first substrate ... Upper surface 53 as a first main surface ... Lower surface 54 as a second main surface ... As a conductor pattern Upper surface side wiring layer 56... Element mounting portion 57 .. via conductor 59 as a conductor portion of the first substrate... Functional module mounting portion 61... Adhesive sheet 62 as the first adhesive layer. Conductor column 71 ... Adhesive sheet 72 as the second adhesive layer ... Conductor column 81 as the conductor part in the second adhesive layer ... Motherboard 82 ... Terminal 91 ... As a functional module Module wiring board 92 ... capacitor constituted by recesses 131 ... passive components as conductor posts 130 ... passive component mounting portion of the conductor portion of the substrate main body 96 ... function modules as an electronic component 95 ... functional module substrate body

Claims (17)

A first substrate having a first main surface and a second main surface, wherein an element mounting portion to which a semiconductor circuit element can be connected is set on the first main surface side;
A second substrate bonded to the second main surface side of the first substrate;
A functional module bonded to at least one of the first main surface and the second main surface of the first substrate, the conductor portion of the first substrate, the conductor portion of the second substrate, and the function A composite wiring board structure characterized in that conductor portions of modules are electrically connected to each other.   The composite wiring board structure according to claim 1, wherein the first board is a flexible wiring board mainly composed of an organic material.   3. The composite wiring board structure according to claim 1, wherein the second substrate is a ceramic substrate mainly composed of an inorganic material.   The passive component mounting part which can connect the passive component which concerns on the operativity improvement of the said semiconductor circuit element is set to the said 2nd board | substrate, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Composite wiring board structure.   4. The composite wiring board structure according to claim 1, wherein the second substrate has a function related to improvement in operability of the semiconductor circuit element. 5.   6. The composite wiring board structure according to claim 1, wherein the functional module is a module wiring board having a circuit including a plurality of types of electronic components.   The second substrate is bonded to the second main surface side of the first substrate via a first adhesive layer, and the conductor portion of the first substrate and the conductor via the conductor portion in the first adhesive layer The composite wiring board structure according to any one of claims 1 to 6, wherein a conductor portion of the second substrate is electrically connected.   The functional module is bonded to at least one of the first main surface and the second main surface of the first substrate via a second adhesive layer, and via a conductor portion in the second adhesive layer. The composite wiring board structure according to claim 1, wherein the conductor portion of the first substrate and the conductor portion of the functional module are electrically connected.   The first substrate has a plurality of conductor patterns fanned out around the element mounting portion as a center, and a plurality of via conductors electrically connected to the plurality of conductor patterns as a multilayer flexible wiring. The composite wiring board structure according to claim 1, wherein the composite wiring board structure is a board.   10. The first substrate according to claim 1, wherein the first substrate is used in a state where a predetermined portion is bent, and the second substrate and the functional module are bonded so as to avoid the bent portion. The composite wiring board structure according to any one of the preceding claims.   11. The composite wiring board structure according to claim 1, wherein the second substrate has a capacitor function for stabilizing a power supply to be supplied to the semiconductor circuit element.   The second substrate has a bonding surface bonded to the first substrate and a non-bonding surface positioned on the opposite side of the bonding surface, and a plurality of terminals included in the motherboard are provided on the non-bonding surface. The composite wiring board structure according to any one of claims 1 to 11, wherein a plurality of external connection terminals connectable to each other are provided. A method for manufacturing a composite wiring board structure according to any one of claims 1 to 12,
An individual manufacturing step of individually manufacturing the first substrate, the second substrate, and the functional module;
The first substrate and the second substrate are joined, and the first substrate and the functional module are joined. At that time, the conductor portion of the first substrate, the conductor portion of the second substrate, and the functional module And a bonding step of electrically connecting the conductor portions to each other.   14. The composite wiring board structure according to claim 13, further comprising an individual inspection step of individually performing an electrical inspection on the first substrate, the second substrate, and the functional module before the bonding step. Manufacturing method. A method for manufacturing a composite wiring board structure according to any one of claims 1 to 12,
An individual manufacturing step of individually manufacturing the first substrate, the second substrate, and a functional module substrate main body to be a part of the functional module;
The first substrate and the second substrate are joined, and the first substrate and the functional module substrate main body are joined. At that time, the conductor portion of the first substrate, the conductor portion of the second substrate, and the A method of manufacturing a composite wiring board structure, comprising: a joining step of electrically connecting conductor portions of the functional module board main body to each other. A first substrate having a first main surface and a second main surface, wherein an element mounting portion to which a semiconductor circuit element can be connected is set on the first main surface side;
A second substrate bonded to the second main surface side of the first substrate,
A functional module mounting portion is set on at least one of the first main surface and the second main surface of the first substrate;
A composite wiring board structure, wherein the conductor portion of the first substrate and the conductor portion of the second substrate are electrically connected to each other.   The composite wiring board structure according to claim 16, wherein a functional module substrate main body that is a part of the functional module is joined to the functional module mounting portion.

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