JP4718890B2 - MULTILAYER WIRING BOARD AND METHOD FOR MANUFACTURING THE SAME, MULTILAYER WIRING BOARD STRUCTURE - Google Patents

Description

  The present invention relates to a multilayer wiring board having a laminated portion formed by laminating a flexible substrate and an adhesive sheet, a manufacturing method thereof, and a multilayer wiring board structure including a multilayer wiring board and a functional module.

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 mother board, 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. As what realizes miniaturization of various parts, for example, a so-called system-in-package (SIP) in which a plurality of LSIs are sealed and systemized can be cited. In such a package, an active element such as an IC chip is embedded in, for example, a circuit board (see, for example, Patent Document 1).
JP 2004-221525A (FIG. 4 etc.)

  By the way, the circuit board described in Patent Document 1 is formed by laminating a plurality of laminated members and thermocompressing them together. For this reason, it is preferable that each laminated member is a material which produces adhesiveness by being softened during heating. For example, it is preferable to mainly use a thermoplastic resin.

  However, a laminated member mainly composed of a thermoplastic resin is plastically deformed when heated. Further, since the IC chip embedded in the circuit board is relatively easy to generate heat, the laminated member is also plastically deformed by heat from the IC chip. For this reason, there is a high possibility that the dimensional stability of the circuit board is lowered. In addition, since the conductor pattern formed on the laminated member is likely to be displaced in the plane direction with plastic deformation of the laminated member, the connection reliability of the IC chip mounted on the conductor pattern is lowered. Therefore, it becomes difficult to achieve electrical connection between the laminated member and the IC chip. As a result, the probability that the completed circuit board becomes a defective product increases, leading to a decrease in yield.

  In order to solve this problem, it is conceivable to mount the IC chip on the main surface of the circuit board by flip chip. However, the flexible substrate constituting the circuit substrate is a substrate that is easily bent in the first place, and therefore has a low coplanarity on the main surface. For this reason, poor connection is likely to occur between the circuit board and the IC chip, and high connection reliability cannot be obtained.

  The present invention has been made in view of the above problems, and a first object thereof is to provide a multilayer wiring board and a multilayer wiring board structure having high dimensional stability and connection reliability. A second object is to provide a method for manufacturing a multilayer wiring board with a low probability of being a defective product and a high yield.

And as a means (means 1) for solving the above-mentioned problem, a flexible substrate having a first via conductor and a conductor pattern extending in the substrate plane direction and an adhesive sheet having a second via conductor are alternately laminated. becomes, a multilayer wiring board comprising a laminate portion having a first major surface and second major surface, wherein the rigid base is embedded in the laminated portion, region directly above the contact Keru the rigid substrate to the first main surface In addition, an element mounting area in which an IC chip as an active element is mounted is set, and a plurality of terminal connection portions are formed in the element mounting area, and the first via conductor, the second via conductor, and the conductor pattern At least one of them also serves as the plurality of terminal connection portions, and the rigid base body is a base body first main surface located on the first main surface side and a base body second located on the second main surface side. Has a main surface, The IC chip has a plurality of external terminals on both the first main surface of the substrate and the second main surface of the substrate, and has a structure in which ceramic dielectric layers and internal electrode layers are alternately stacked. The ceramic capacitor is a passive component involved in the improvement, the area of the first main surface of the substrate is set larger than the area of the element mounting region, the plurality of external terminals on the first main surface of the substrate, The plurality of external terminals that are electrically connected to the plurality of terminal connection portions via at least one of the first via conductor and the second via conductor, There is a multilayer wiring board characterized in that it is electrically connected to a plurality of terminals on the second main surface through at least one of one via conductor and the second via conductor .

Further, as another means (means 2) for solving the above-mentioned problem, a plurality of adhesive sheets having at least one of a via conductor and a conductor pattern extending in the sheet plane direction are laminated, and the first main surface and a multilayer wiring board having a multilayer portion having a second major surface, wherein the rigid base is embedded in the laminated portion in the region directly above the contact Keru the rigid substrate to the first main surface, is an active element An element mounting area on which the IC chip is mounted is set, and a plurality of terminal connection portions are formed in the element mounting area, and at least one of the via conductor and the conductor pattern includes the plurality of terminal connection sections. The rigid base includes a base first main surface located on the first main surface side and a base second main surface located on the second main surface side, and the base first main surface and the base Both base 2nd main surface A ceramic capacitor having a plurality of external terminals, having a structure in which ceramic dielectric layers and internal electrode layers are alternately laminated, and being a passive component involved in improving the operability of the IC chip, An area of one main surface is set larger than an area of the element mounting region, and the plurality of external terminals on the first main surface of the base are electrically connected to the plurality of terminal connection portions via the via conductors. And the plurality of external terminals on the second main surface of the base body are electrically connected to the plurality of terminals on the second main surface via the via conductors. There is a multilayer wiring board.

  Therefore, according to the multilayer wiring board of the above means 1 and 2, since the element mounting area is set on the outer surface of the laminated part, even when the element is mounted, the heat is easily dissipated outside the laminated part. . For this reason, plastic deformation of the laminated portion due to the influence of heat is prevented. Therefore, a multilayer wiring board with high dimensional stability can be obtained. In addition, since the rigid base having a high mechanical strength is embedded, the laminated portion is partially reinforced to make it difficult to bend, so that the coplanarity of the element mounting region is increased. Therefore, poor connection at the terminal connection portion is less likely to occur, and high connection reliability can be obtained.

  The flexible substrate according to the means 1 may be present in only one layer, but preferably present in two or more layers (multilayers). In this way, compared to the case where the flexible substrate is not multi-layered (only one layer), it is possible to configure more circuits inside, and the added value can be increased. In addition, it is preferable that the flexible substrate has a first substrate main surface and a second substrate main surface, and the conductor pattern is formed on both the first substrate main surface and the second substrate main surface. In this way, compared to the case where the conductor pattern is formed on either the first main surface of the substrate or the second main surface of the substrate, it becomes possible to configure more circuits inside, and the like. Value can be increased.

Moreover, when forming a laminated part by thermocompression bonding, it is preferable that flexible substrates are adhere | attached through the adhesive sheet which produces adhesiveness by heating. At this time, only one layer of the adhesive sheet may exist between the flexible substrates, or two or more layers (multilayers) may exist. In addition, when the flexible substrate is mainly composed of a non-thermoplastic resin and the adhesive sheet is mainly composed of a thermoplastic resin, it is preferable that only one layer of the adhesive sheet exists. In this way, compared to the case where there are two or more adhesive sheets, the adhesive sheet is less likely to be plastically deformed at the time of thermocompression bonding, so that the dimensional stability of the laminated portion is unlikely to be lowered. Therefore, the flexible substrate and the adhesive sheet are preferably laminated alternately. In addition, when the element which can be mounted in an element mounting area | region is thick, a lamination | stacking part is partially reinforced and dimensional stability becomes high. Therefore, the portion corresponding to the element mounting region in the stacking direction may have a structure in which only adhesive sheets are stacked. If it does in this way, adhesiveness will become high. Moreover, since many adhesive sheets which do not have a conductor pattern are used, a laminated part can be formed at low cost. A part of the flexible substrate may be bent and laminated on the adhesive sheet located on the upper layer side in the laminated portion.

  The resin material for forming the flexible substrate can be appropriately selected from non-thermoplastic resins in consideration of cost, workability, insulation, flexibility, mechanical strength, and the like. With such a resin substrate, a fine wiring layer can be formed relatively easily and accurately, and a terminal connection portion that can connect an element with a very large number of terminals can be easily formed. Can do. That is, such a substrate is suitable as a device mounting substrate.

  Moreover, it is preferable that the material which forms a flexible substrate has heat resistance. Specifically, the resin material preferably has a glass transition temperature (Tg) of 220 ° C. or higher. The resin material preferably has a heat resistance of, for example, 260 ° C. and a level of 10 minutes or more, and more preferably a heat resistance of 300 ° C. and a level of 10 minutes or more. Further, the resin material preferably has a solder heat resistance of 250 ° C. and a level of 20 seconds or more, and particularly preferably has a solder heat resistance of 260 ° C. and a level of 120 seconds or more. It is more preferable that the properties are 300 ° C. and 180 seconds or more. This is because even if the laminated portion is formed by thermocompression bonding, for example, deformation of the flexible substrate can be prevented.

  Preferable examples of the non-thermoplastic resin that forms the insulating portion of the flexible substrate include polyimide resin, polyamideimide resin, and polyamide resin. 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.

  The adhesive sheets according to the means 1 and 2 are preferably formed mainly of an organic material made of a thermoplastic resin so that the flexible substrates can be thermocompression bonded at the time of forming the laminated portion. Moreover, it is preferable that an adhesive sheet is flexible like a flexible substrate. If it does in this way, the flexibility of a lamination part can be maintained about fields other than the field corresponding to the embedding part of the rigid base. As the thermoplastic resin forming the insulating portion of the adhesive sheet, for example, liquid crystal polymer, thermoplastic polyimide, polyether ether ketone, and the like are suitable. If such a material is used, it becomes easy to realize a multilayer wiring board excellent in connection reliability at a high temperature. Furthermore, it is preferable that the adhesive sheet also functions as a cover lay for the flexible substrate. Here, the coverlay generally refers to an insulating coating layer (protective film) that covers the surface of the flexible substrate except a part of the conductor pattern. In this way, it is not necessary to form a protective film for the flexible substrate separately from the adhesive sheet. As a result, the multilayer wiring board can be reduced in size in the thickness direction (Z direction). Further, the number of parts and man-hours constituting the multilayer wiring board are reduced, and it becomes easy to achieve improvement in production efficiency and reduction in manufacturing cost. Furthermore, the structure of the multilayer wiring board can be simplified. The adhesive sheet that also functions as a cover lay for the flexible substrate is preferably located in the outermost layer of the laminated portion. If it does in this way, the surface conductor part which is most easily damaged in the laminated part can be protected.

  The first via conductor and conductive pattern of the flexible substrate and the second via conductor of the adhesive sheet are formed of, for example, a conductive metal. 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.

  The rigid base is a member mainly composed of a material that does not have flexibility and has higher mechanical strength than the flexible substrate and the adhesive sheet. For this reason, the Young's modulus of the rigid substrate is preferably set to 0.1 GPa or more, for example, and more preferably set to 1 GPa or more and 500 GPa or less. The thermal expansion coefficient in the planar direction of the rigid base is preferably set lower than the thermal expansion coefficient in the planar direction of the laminated portion, and is preferably set to, for example, 5 ppm / ° C. or more and 13 ppm / ° C. or less. If the thermal expansion coefficient is 13 ppm / ° C. or less, the rigid base is less likely to be plastically deformed by heat, and the laminated portion is less likely to be bent, so that the coplanarity of the element mounting region can be maintained. Further, when the element that can be mounted in the element mounting area is formed of silicon (thermal expansion coefficient is around 3 ppm / ° C.), the difference between the thermal expansion coefficient in the plane direction of the rigid substrate and the thermal expansion coefficient in the plane direction of the element. Is preferably set to 3 ppm / ° C. or more and 8 ppm / ° C. or less, for example. An example of such a rigid substrate is a glass ceramic wiring board.

  The material for forming the rigid substrate can be appropriately selected in consideration of cost, workability, insulation, mechanical strength, and the like. Examples of the rigid base include substantially flat members mainly made of metal, resin, ceramic, and the like.

  The rigid base may be a passive component involved in improving the operability of an active element (for example, an element mounted in an element mounting area), for example, for stabilizing a power supply to be supplied to the element. It is preferably a passive component. Specific examples of this type of passive component include a diode, a resistor, an inductor, a capacitor, and a coil. Note that these passive components are preferably substantially flat and have higher mechanical strength than the flexible substrate and the adhesive sheet.

  Furthermore, the rigid substrate may be a wiring board provided with a passive component that is provided with a wiring layer and is involved in improving the operability of the active element. This is because, unlike the case where the rigid base does not have a wiring layer, it is possible to configure a circuit therein, and the added value of the multilayer wiring board can be increased. Examples of the wiring board include a ceramic wiring board, a resin wiring board, a metal wiring board, and a Si wiring board. In particular, the rigid substrate is preferably a ceramic wiring substrate mainly composed of an inorganic material. This is because ceramic is excellent in rigidity, so that the mechanical strength of the laminated portion can be increased. 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 wiring board include, but are not limited to, an alumina wiring board, an aluminum nitride wiring board, a beryllia wiring board, a glass ceramic wiring board, and a wiring board made of a low-temperature fired material such as crystallized glass. There is nothing.

  Further, as an aspect of embedding the rigid base in the laminated portion, for example, it is conceivable to embed (that is, incorporate) the entire rigid base. When comprised in this way, a rigid base | substrate can be reliably protected by a laminated part. As another method, it is conceivable to embed the rigid substrate with only a part of the rigid substrate exposed. When configured in this manner, it becomes easy to dissipate the heat generated from the rigid base to the outside of the laminated portion.

  In addition, it is preferable that the area of the first substrate main surface located on the first main surface side in the rigid substrate is the same as or slightly larger than the area of the element mounting region. If the area of the first main surface of the substrate is smaller than the area of the element mounting area, it is difficult to reliably reinforce the element mounting area in the stacked portion. On the other hand, if the area of the first main surface of the substrate is too large (for example, 10 times or more) compared to the area of the element mounting region, the volume ratio of the rigid substrate in the stacked portion becomes too large. It becomes difficult to compose. Further, since the entire laminated portion is reinforced by embedding the rigid base, the flexibility of the laminated portion is easily lost.

  The thickness of the rigid substrate is preferably set to 50 μm or more and 200 μm or less, although it depends on the thickness of the laminated portion. If it does in this way, while being able to ensure the high mechanical strength of a rigid base, the enlargement to the thickness direction (Z direction) of a lamination part can be prevented.

  The element mounting region can be freely set on at least one of the first main surface and the second main surface, but can be set to a region corresponding to the embedded portion of the rigid base. preferable. In this way, since the elements that can be mounted in the element mounting area are supported more directly by the rigid base, the elements are more reliably fixed and the connection reliability is higher. Note that only one element mounting region may be set in at least one of the first main surface and the second main surface, but a plurality of device mounting regions may be set.

  The rigid base includes a base first main surface located on the first main surface side and a base second main surface located on the second main surface side, and the base first main surface and the base first It is preferable to have a plurality of external terminals on at least one of the two main surfaces. In this way, it is possible to configure a complicated circuit inside the rigid base, so that added value can be increased. The rigid base includes a base first main surface located on the first main surface side and a base second main surface located on the second main surface side, and the base first main surface and the base first It is preferable to have a plurality of external terminals on each of the two main surfaces. In this way, the degree of freedom of wiring is increased as compared with the case where a plurality of external terminals are provided on either the first main surface of the base or the second main surface of the base.

  The plurality of external terminals on the first main surface of the base are electrically connected to the plurality of terminal connection portions via at least one of the first via conductor and the second via conductor. Preferably it is. In this way, the length of the wiring connecting the rigid base and the element mounting area is shortened, so that the signal speed between the rigid base and the element mounting area can be increased. Further, when the rigid base is a capacitor, the power supply can be stabilized by reducing the inductance between the capacitor and the element mounting region.

  Further, as another means (means 3) for solving the above problems, the multilayer wiring board of means 1 and 2 and a functional module bonded to a part of the multilayer wiring board are provided. There is a multilayer wiring board structure characterized.

  Therefore, according to the multilayer wiring board structure of the above means 3, since the element mounting region is set on the outer surface of the laminated part, even when the element is mounted, the heat is easily dissipated outside the laminated part. . For this reason, plastic deformation of the laminated portion due to the influence of heat is prevented. Therefore, a multilayer wiring board with high dimensional stability can be obtained. In addition, since the rigid base having a high mechanical strength is embedded, the laminated portion is partially reinforced to make it difficult to bend, so that the coplanarity of the element mounting region is increased. Therefore, poor connection at the terminal connection portion is less likely to occur, and high connection reliability can be obtained.

  In addition, since the multilayer wiring board structure of the present invention has a functional module in addition to the multilayer wiring board, it can be multi-functional as compared with a case where no functional module is provided. Therefore, it becomes easy to realize a single systemized multilayer wiring board structure (so-called system-in-package: SIP), and the added value is also increased.

  In addition, since the element mounted in the element mounting region is located outside the stacked portion, heat generated from the element is easily dissipated outside the stacked portion. Therefore, malfunction of the element due to the influence of heat can be prevented.

  Examples of elements to be mounted in the element mounting region include passive elements such as capacitors and active elements such as semiconductor circuit elements. Examples of the semiconductor circuit element include 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. 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 element are not particularly limited, but the area of the element mounting region is preferably set smaller than the areas of the first main surface and the second main surface of the rigid substrate. In this way, the element mounting region in the stacked portion is reliably reinforced by the rigid base, so that the element can be reliably supported.

  The size of the rigid base is not particularly limited as long as it is smaller than the housing space for housing the rigid base, but is preferably substantially the same size as the housing space. In this way, since the rigid base is supported in contact with the inner surface of the housing space, the position of the rigid base is fixed and the connection reliability is easily maintained. Moreover, it is preferable that the said rigid base | substrate has a base | substrate 1st main surface located in the said 1st main surface side, and a base | substrate 1st main surface is surface-contacted to the said adhesive sheet. In the case where a plurality of external terminals are provided on the first main surface of the base, it is preferable that the plurality of terminal connection portions are formed in a portion of the adhesive sheet that faces the first main surface of the base. Similarly, it is preferable that the rigid substrate has a second substrate main surface located on the second main surface side, and the second substrate main surface is in surface contact with the adhesive sheet. In the case where a plurality of external terminals are provided on the second main surface of the base, it is preferable that the plurality of terminal connection portions are formed on a portion of the adhesive sheet that faces the second main surface of the base. According to this configuration, since the base first main surface and the base second main surface of the rigid base are fixed by the adhesive sheet, the rigid base is stably connected to the terminal connection portion. Therefore, it becomes easy to maintain the connection reliability of the rigid base. Furthermore, it is preferable that the adhesive sheet on which a plurality of terminal connection portions are formed simultaneously perform connection with the rigid base and bonding with the flexible substrate. In this way, the number of steps for configuring the multilayer wiring board is reduced, and it becomes easy to achieve improvement in production efficiency and reduction in manufacturing cost. The rigid substrate has side surfaces orthogonal to the first substrate main surface and the second substrate main surface, and the side surfaces are in surface contact with a flexible substrate and an adhesive sheet constituting a part of the inner surface of the housing space. Is more preferable. According to this configuration, the side surface of the rigid base is fixed by the flexible substrate and the adhesive sheet, so that the rigid base is more stably connected to the terminal connection portion. Therefore, it becomes easier to maintain the connection reliability of the rigid base. Note that only one rigid base may be accommodated in the accommodating space, or two or more rigid bases may be accommodated in the accommodating space.

  In addition, as a joining location of the said functional module, on the said flexible substrate or the said adhesive sheet etc. are mentioned. The functional module may be a module wiring board having a circuit including 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.

  As a preferable method (means 4) for producing the multilayer wiring board according to means 1 relatively easily and surely, an individual production step of individually producing the flexible substrate, the adhesive sheet, and the rigid substrate, And forming the laminated portion by laminating and bonding the flexible substrate and the adhesive sheet, and at that time, the second via conductor is formed on at least one of the first via conductor and the conductor pattern. There is a manufacturing method of a multilayer wiring board characterized by including a joining step of electrically connecting and embedding the rigid base in the laminated portion.

  Therefore, according to the means 4, the flexible substrate, the adhesive sheet, and the rigid base are individually manufactured in the individual manufacturing process before the stacked portion is formed, so that these electrical inspections can be performed individually. Therefore, since a defective product can be found and removed in advance before bonding, only the flexible substrate, the adhesive sheet, and the rigid substrate that have passed the electrical inspection can be bonded to form a laminated portion. Therefore, the probability that the multilayer wiring board becomes a defective product is reduced, leading to an improvement in yield.

  Further, since the element mounting area is set on the outer surface of the laminated portion, even when the element is mounted, the heat is easily dissipated to the outside of the laminated portion. For this reason, plastic deformation of the laminated portion due to the influence of heat is prevented. Therefore, a multilayer wiring board with high dimensional stability can be obtained. In addition, since the rigid base having a high mechanical strength is embedded, the laminated portion is partially reinforced to make it difficult to bend, so that the coplanarity in the element mounting region is increased. Therefore, poor connection at the terminal connection portion is less likely to occur, and high connection reliability can be obtained.

  Further, when performing the joining step, the flexible substrate and the adhesive sheet are joined, and at the same time, the rigid base is embedded, so that the multilayer wiring board can be efficiently manufactured.

  Further, as a preferable method (means 5) for producing the multilayer wiring board described in the means 2 relatively easily and surely, an individual production process for individually producing the plurality of adhesive sheets and the rigid substrate, A bonding step of forming a laminated portion by laminating and bonding the plurality of adhesive sheets, electrically connecting the via conductors at that time, and embedding the rigid base in the laminated portion; There is a manufacturing method of a multilayer wiring board characterized by including:

  Therefore, according to the above means 5, since the adhesive sheet and the rigid base are individually manufactured in the individual manufacturing process before the stacked portion is formed, both electrical inspections can be performed individually. Therefore, since a defective product can be found and removed in advance before joining, only the adhesive sheet and the rigid substrate that have passed the electrical inspection can be joined to form a laminated portion. Therefore, the probability that the multilayer wiring board structure becomes a defective product is reduced, leading to an improvement in yield.

  Further, since the element mounting area is set on the outer surface of the laminated portion, even when the element is mounted, the heat is easily dissipated to the outside of the laminated portion. For this reason, plastic deformation of the laminated portion due to the influence of heat is prevented. Therefore, a multilayer wiring board with high dimensional stability can be obtained. In addition, since the rigid base having a high mechanical strength is embedded, the laminated portion is partially reinforced to make it difficult to bend, so that the coplanarity in the element mounting region is increased. Therefore, poor connection at the terminal connection portion is less likely to occur, and high connection reliability can be obtained.

  Further, when the bonding step is performed, a plurality of adhesive sheets are bonded, and at the same time, the rigid base is embedded, so that a multilayer wiring board can be manufactured efficiently.

  Hereinafter, a method for manufacturing the multilayer wiring board described in Means 4 will be described.

  First, an individual production process is performed to individually produce a flexible substrate, an adhesive sheet, and a rigid base.

  Fabrication of the flexible substrate in the individual fabrication process is 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 forming a first via conductor by filling the via hole with a conductive metal paste or copper plating, the surface copper foil is etched to pattern the conductor pattern.

  The production of the adhesive sheet in the individual production process is performed as follows. For example, a via hole communicating with the adhesive sheet base material is formed at a predetermined position on the adhesive sheet base material to be an adhesive sheet (via hole forming step). Furthermore, a second via conductor is formed by filling each via hole with a paste made of a conductive metal (second via conductor forming step). And an adhesive sheet is completed by heating a paste, evaporating a solvent etc. and solidifying. Note that the second via conductor may be formed by plating, for example, instead of filling the paste made of a conductive metal. In addition, a conductive metal column may be embedded in the via hole.

  Further, when the rigid base is, for example, a ceramic capacitor having a dielectric layer and an electrode layer, the manufacture of the rigid base in the individual manufacturing process is basically performed according to a conventionally known method. For example, a dielectric green sheet is sintered to form a ceramic dielectric layer, and a metal material is deposited on the dielectric layer to form an electrode. In addition, a metal paste is applied to the dielectric green sheet or a metal sheet is laminated and sintered simultaneously.

  Next, a joining process is performed. In the joining step, a flexible substrate and an adhesive sheet are laminated and a rigid substrate is placed, and in this state, for example, a pressing force is applied in the lamination direction while heating. As a result, the flexible substrate and the adhesive sheet are joined, and at this time, the second via conductor of the adhesive sheet is electrically connected to at least one of the first via conductor and the conductor pattern of the flexible substrate. The In addition, the heating temperature at this time is suitably set according to the kind of material of the flexible substrate, the kind of the adhesive sheet to be used, the degree of curing of the adhesive sheet, and the like. Further, the heating temperature is preferably set higher than the melting point of the solder used after the joining step. Furthermore, the solder heat resistance of the flexible substrate and the adhesive sheet is preferably set to a temperature higher than the melting point of the solder. If it does in this way, when using solder after a joining process, deformation of a flexible substrate or an adhesive sheet can be prevented.

  As a result, a laminated portion composed of the flexible substrate and the adhesive sheet is formed, and at the same time, a rigid base is embedded in the laminated portion. The operation of connecting the plurality of terminals of the element to the plurality of terminal connection portions formed in the element mounting region may be performed simultaneously with the bonding process or after the bonding process. It is preferable to perform the bonding process at the same time. In this way, since the number of steps is reduced, the manufacturing cost can be reduced.

  DESCRIPTION OF EMBODIMENTS 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 multilayer wiring board structure 10 of the present embodiment including a multilayer wiring board 11 having a laminated portion 12 and the like. FIG. 2 is an exploded cross-sectional view showing the configuration of the multilayer wiring board 11. FIG. 3 is an enlarged cross-sectional view showing the vicinity of the ceramic capacitor 131 (rigid substrate, passive component) of the multilayer portion 12. 4 and 5 are schematic explanatory views for explaining connections in the inner layer of the ceramic capacitor 131. FIG. FIG. 6 is an exploded cross-sectional view illustrating a configuration of a structure including a flexible wiring board (flexible board) 51a, a board body 95, and the like. FIG. 7 is a schematic cross-sectional view showing the adhesive organic material sheet 60. 8 and 9 are schematic cross-sectional views showing a state when the adhesive sheet 61b is produced. 10 and 11 are schematic cross-sectional views showing a state when the adhesive sheet 61c is produced. FIG. 12 is a schematic cross-sectional view showing a state where the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d are joined to form the laminated portion 12. FIG. 13 is a schematic cross-sectional view showing a state when the flexible wiring boards 51a and 51b and the board body 95 are joined to each other.

  As shown in FIGS. 1 and 2, the multilayer wiring board structure 10 of the present embodiment has a multilayer wiring board 11 including a laminated portion 12. The stacked portion 12 has an upper surface 13 (first main surface) and a lower surface 14 (second main surface). The laminated portion 12 has flexibility, and has a structure in which two flexible wiring boards 51a and 51b and four adhesive sheets 61a, 61b, 61c, and 61d are laminated. Specifically, the adhesive sheet 61a, the flexible wiring board 51a, the adhesive sheet 61b, the flexible wiring board 51b, and the adhesive sheet 61c are laminated in order. The right side portions of the flexible wiring boards 51a and 51b and the adhesive sheets 61b and 61c are bent upward by 180 °, and the right side portions thereof are stacked on the adhesive sheet 61c. Further, an adhesive sheet 61d is laminated on the right side portion bent upward in the flexible wiring board 51a.

  The flexible wiring boards 51a and 51b are mainly formed of an insulating base material made of a heat-resistant non-thermoplastic resin (non-thermoplastic polyimide in this embodiment). In addition, the glass transition temperature (Tg) of flexible wiring board 51a, 51b is 270 degreeC, Comprising: It is higher than the heating temperature at the time of forming the laminated part 12. FIG. The heat resistance (long-term heat resistance) is 300 ° C. for 30 minutes, and the solder heat resistance is 300 ° C. for 180 seconds.

  Further, the flexible wiring boards 51 a and 51 b have a substrate first main surface 52 and a substrate second main surface 53. A first main surface side wiring layer 54 (conductor pattern) extending in the substrate plane direction is formed on the substrate first main surface 52, and a second main surface side that also extends in the substrate plane direction is formed on the substrate second main surface 53. A wiring layer 55 (conductor pattern) is formed. The flexible wiring boards 51 a and 51 b are provided with a plurality of first via conductors 57 that penetrate the substrate first main surface 52 and the substrate second main surface 53. The first end surface of each first via conductor 57 is electrically connected to the first main surface side wiring layer 54, and the second end surface of each first via conductor 57 is electrically connected to the second main surface side wiring layer 55. Has been. Accordingly, the first main surface side wiring layer 54 and the second main surface side wiring layer 55 are electrically connected to the first via conductor 57. Note that the flexible wiring board 51 b located on the inner layer side of the stacked portion 12 constitutes the upper surface of the accommodation space 130 and constitutes part of the side surface of the accommodation space 130. The flexible wiring board 51 a located on the outer layer side of the stacked unit 12 constitutes the lower surface of the accommodation space 130.

  As shown in FIGS. 1 and 2, the adhesive sheet 61 d located in the uppermost layer of the laminated portion 12 covers the substrate first main surface 52 side of the flexible wiring board 51 a located in the uppermost layer of the laminated portion 12. Yes. Further, the adhesive sheet 61 a located in the lowermost layer of the laminated portion 12 covers the substrate first main surface 52 side of the flexible wiring substrate 51 a located in the lowermost layer of the laminated portion 12. Therefore, the adhesive sheets 61a and 61d located in the uppermost layer and the lowermost layer protect the first main surface side wiring layer 54 from dust and moisture. For this reason, the adhesive sheets 61a and 61d located in the uppermost layer and the lowermost layer of the laminated portion 12 also function as a cover lay for the flexible wiring board 51a. Further, the adhesive sheets 61 a to 61 d have via holes 66 for exposing a part of the first main surface side wiring layer 54. Note that the adhesive sheet 61 c located in the inner layer of the stacked portion 12 constitutes a part of the side surface of the accommodation space 130. The adhesive sheet 61b has a function of bonding the flexible wiring boards 51a and 51b, and the adhesive sheet 61c has a function of bonding the flexible wiring boards 51b.

  As shown in FIGS. 1 and 2, the adhesive sheets 61 a to 61 d are mainly formed of an insulating base material made of a heat-resistant thermoplastic resin. In this embodiment, the insulating base material is formed of thermoplastic polyimide (AURUM, manufactured by Mitsui Chemicals, Inc.). The adhesive sheets 61a to 61d are formed thicker than the first main surface side wiring layer 54 and the second main surface side wiring layer 55, and are set to a thickness of about 10 to 30 μm. In addition, the glass transition temperature (Tg) of adhesive sheet 61a-61d is 250 degreeC, and is lower than the glass transition temperature of flexible wiring board 51a, 51b. The adhesive sheet main body 63 constituting the adhesive sheets 61 a to 61 d has a sheet first main surface 64 and a sheet second main surface 65. The adhesive sheets 61a to 61d are formed with a plurality of via holes 66 (see FIG. 8) communicating with the sheet first main surface 64 and the sheet second main surface 65 in a lattice shape. The via hole 66 is provided with a second via conductor 62 (via conductor) formed by filling a conductive paste containing copper powder whose surface is coated with silver. In addition, the adhesive sheets 61a to 61d of the present embodiment do not have a conductor pattern extending in the sheet plane direction.

  As shown in FIGS. 1 and 2, in the adhesive sheet 61 d, the base end surface of each second via conductor 62 is connected to the first main surface side wiring layer 54 of the flexible wiring substrate 51 a located in the uppermost layer of the laminated portion 12. Electrically connected. In the adhesive sheet 61c located in the inner layer of the laminated portion 12, the distal end surface and the proximal end surface of each second via conductor 62 are electrically connected to the second main surface side wiring layer 55 of the flexible wiring substrate 51b. In the adhesive sheet 61b located in the inner layer of the laminated portion 12, the front end surface of each second via conductor 62 is electrically connected to the second main surface side wiring layer 55 of the flexible wiring substrate 51a. Further, in the adhesive sheet 61 b, the base end surface of each second via conductor 62 is electrically connected to the first main surface side wiring layer 54 of the flexible wiring substrate 51 b located in the inner layer of the laminated portion 12. In the adhesive sheet 61a located in the lowermost layer of the laminated portion 12, the front end surface of each second via conductor 62 is electrically connected to the first main surface side wiring layer 54 of the flexible wiring substrate 51a. Further, in the adhesive sheet 61a, a plurality of solder bumps 49 for electrical connection with the plurality of terminals 82 of the mother board 81 are arranged in a lattice pattern on the lower end surface of each second via conductor 62. . The solder bump 49 is made of tin-lead solder having a composition of 90 Pb / 10 Sn.

  The multilayer wiring board structure 10 shown in FIG. 1 is mounted on the mother board 81 by the solder bumps 49. The multilayer wiring board structure 10 is a BGA (ball grid array) composed of the laminated portion 12 and the module wiring board 91 (functional module). The form of the multilayer wiring board structure 10 is not limited to only BGA, but may be LGA (land grid array), PGA (pin grid array), or the like.

  As shown in FIGS. 1 and 3, a ceramic capacitor 131 is embedded in the multilayer portion 12. The ceramic capacitor 131 is disposed in the accommodating space 130 having a substantially rectangular shape in plan view. The ceramic capacitor 131 of the present embodiment is a so-called via array type multilayer ceramic capacitor having a rectangular flat plate shape of 6.0 mm long × 6.0 mm wide × 0.5 mm thick. The ceramic capacitor 131 has a capacitor upper surface 23 (base first main surface) located on the upper surface 13 side of the multilayer portion 12 and a capacitor lower surface 24 (base second main surface) located on the lower surface 14 side of the multilayer portion 12. It is a plate. The capacitor upper surface 23 is in surface contact with the flexible wiring board 51b that forms the upper surface of the accommodation space 130. On the other hand, the capacitor lower surface 24 is in surface contact with the adhesive sheet 61 b constituting the bottom surface of the accommodation space 130. The ceramic capacitor 131 has a structure in which a large number of ceramic dielectric layers 136 and a large number of internal electrode layers 141 and 142 are alternately stacked. The ceramic dielectric layer 136 is made of a sintered body of barium titanate, which is a kind of high dielectric constant ceramic, and functions as a dielectric (insulator) between the internal electrode layers 141 and 142. The thickness of the ceramic dielectric layer 136 is set to about 5 μm. The thermal expansion coefficient in the plane direction of the ceramic dielectric layer 136 is 8.3 to 11.6 ppm / ° C. For example, the thermal expansion coefficient at 30 to 300 ° C. is 10.2 ppm / ° C. The Young's modulus of the ceramic dielectric layer 136 is 107.5 GPa. Therefore, the ceramic capacitor 131 of this embodiment has relatively high rigidity. Each of the internal electrode layers 141 and 142 is a layer formed of nickel as a main component and having a thickness of about 1.5 μm to 1.8 μm, and is disposed every other layer inside the ceramic capacitor 131. In the present embodiment, ceramic capacitors 131 having different dimensions, Young's modulus, and thermal expansion coefficients may be used. For example, the dimensions are 1.0 cm length × 1.0 cm width × 0.5 mm thickness, the thermal expansion coefficient in the plane direction of the ceramic dielectric layer 136 is 9.2 to 11.6 ppm / ° C., and the Young's modulus is 107.0 GPa. A ceramic capacitor 131 may be used.

  As shown in FIGS. 1 and 3, the ceramic capacitor 131 is formed with a large number of via holes 143 having an inner diameter of about 100 μm. In each via hole 143, 196 via conductors 134 and 137 penetrating between the capacitor upper surface 23 and the capacitor lower surface 24 are formed using nickel as a main material. These via conductors 134 and 137 are arranged in a lattice shape (array shape) over the entire upper surface 23 and lower surface 24 of the capacitor. The distance (pitch) between the centers of the adjacent via conductors 134 and 137 is set to about 300 μm. In this embodiment, the pitch between the via conductors 134 and 137 is equal both in the vertical direction (the thickness direction in FIG. 1) of the ceramic capacitor 131 and in the horizontal direction (the horizontal direction in FIG. 1). Each via conductor 134 passes through each internal electrode layer 141 and electrically connects them to each other. On the other hand, as shown in FIG. 5 and the like, each via conductor 134 is electrically insulated from each internal electrode layer 142 by passing through a clearance hole 144 provided in each internal electrode layer 142. Each via conductor 137 penetrates each internal electrode layer 142 and electrically connects them to each other. On the other hand, as shown in FIG. 4 and the like, each via conductor 137 is electrically insulated from the internal electrode layer 141 by passing through a clearance hole 145 provided in the internal electrode layer 141.

  Then, energization is performed from the mother board 81 side through the second main surface side wiring layer 55 of the flexible wiring board 51a, the second via conductor 62 of the adhesive sheet 61b, and the like. In the present embodiment, the lower end portions of the via conductors 134 and 137 serve as external terminals of the ceramic capacitor 131. When a voltage is applied between the internal electrode layer 141 and the internal electrode layer 142, for example, positive charges are accumulated in the internal electrode layer 141, and negative charges are accumulated in the internal electrode layer 142. As a result, the ceramic capacitor 131 functions as a capacitor. In the present embodiment, the ceramic capacitor 131 has a function of removing noise and stabilizing the power to be supplied to the IC chip 21, and is involved in improving the operability of the IC chip 21.

  As shown in FIGS. 1 and 2, a predetermined region (specifically, a region directly above the ceramic capacitor 131) on the upper surface 13 of the multilayer portion 12 is a part of the first main surface side wiring layer 54. An element mounting region 50 in which a plurality of flip chip connection pads are arranged is set. In the element mounting region 50, a plurality of terminal connection portions 56 are set. A part of the first main surface side wiring layer 54 included in the flexible wiring substrate 51 a and the second via conductor 62 included in the adhesive sheet 61 d also serve as a plurality of terminal connection portions 56. Each terminal connection portion 56 is electrically connected to the surface connection terminal 22 of the IC chip 21 (active element) having a function as an MPU. The IC chip 21 of the present embodiment is a rectangular flat plate of 4.0 mm long × 4.0 mm wide × 0.7 mm thick, and is made of silicon. That is, the area of the IC chip 21 (element mounting region 50) is slightly smaller than the area of the capacitor upper surface 23 of the ceramic capacitor 131. Circuit elements (not shown) are formed on the lower surface layer of the IC chip 21. A plurality of surface connection terminals 22 are provided in a lattice pattern on the lower surface side of the IC chip 21.

  As shown in FIGS. 1 and 6, the flexible wiring board 51 a located at the uppermost layer of the stacked unit 12 has a portion (projected portion 58) that projects in the planar direction of the stacked unit 12. The module wiring board 91 is bonded to the upper surface side of the projecting portion 58. In the present embodiment, the module wiring board 91 is established as a power supply 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 having 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 made of copper plating are provided in the via holes. . 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.

  Further, the module wiring board 91 is joined to the substrate first main surface 52 side of the flexible wiring board 51a through the adhesive sheet 61d. The module wiring board 91 may be joined to the substrate second main surface 53 side of the flexible wiring board 51a via the adhesive sheet 61b. As shown in FIG. 1, the distal end surface of each second via conductor 62 is electrically connected to the lower surface side pad 99 of the substrate body 95, and the proximal end surface of each second via conductor 62 is the above-described second wiring conductor 51 a. The first main surface side wiring layer 54 is electrically connected.

  As a result, a current flows through a path (or a path opposite thereto) of the upper surface side pad 97 to the conductor pillar 96 to the lower surface side pad 99 to the second via conductor 62. Therefore, in the multilayer wiring board structure 10 having such a structure, the flexible wiring board 51 a side and the electronic component 92 side are electrically connected via the conductor pillar 96 of the board body 95. Therefore, signal input / output is performed between the flexible wiring board 51 a and the electronic component 92 via the module wiring board 91.

  Therefore, in the multilayer wiring board structure 10 having such a structure, when the IC chip 21 is mounted in the element mounting region 50, the surface connection terminals 22 of the IC chip 21 are connected to the first main surface side wiring layer 54 (flip chip). It is electrically connected to the first via conductor 57 of the flexible wiring board 51a via the connection pad). Therefore, signals are input / output between the stacked unit 12 and the IC chip 21 and power for operating the IC chip 21 as an MPU is supplied.

  Next, a procedure for manufacturing the multilayer wiring board structure 10 will be described.

  First, an individual manufacturing process is performed, and the flexible wiring boards 51a and 51b, the adhesive sheets 61a to 61d, and the ceramic capacitor 131 are individually manufactured. The flexible wiring boards 51a and 51b in the individual manufacturing process are basically manufactured 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. Further, a through hole 132 (see FIG. 2) that will later become the accommodation space 130 is formed in advance at a predetermined position of the copper clad laminate. Then, the first via conductor 57 is formed in the via hole by performing electroless copper plating and electrolytic copper plating according to a conventionally known method. Further, the first main surface side wiring layer 54 and the second main surface side wiring layer 55 are formed by etching both surfaces of the copper clad laminate. As a result, flexible wiring boards 51a and 51b are obtained.

Moreover, the adhesive sheets 61a-61d are produced in an individual production process. Specifically, the adhesive organic material sheet 60 (see FIG. 7) to be the adhesive sheets 61a to 61d is punched using a mechanical drill, YAG laser, CO ₂ laser, punching device, etc. A via hole 66 (see FIGS. 8 and 10) penetrating the organic material sheet 60 is formed in advance at a predetermined position (via hole forming step). Further, as shown in FIG. 10, a through-hole 133 that will later become the accommodation space 130 is formed in advance at a predetermined position of the adhesive organic material sheet 60. The via hole 66 has an upper opening having a diameter of approximately 117 μm and a lower opening having a diameter of approximately 113 μm.

Next, the second via conductor 62 is formed by filling the via hole 66 with a conductive paste by a conventionally known printing method. Specifically, the adhesive organic material sheet 60 is placed on a support base (not shown). Next, using a printing mask having an opening at a position corresponding to the via hole 66, the printing pressure is set to 2 kgf / cm ² , the printing speed is set to 50 mm / sec, and the surface contains copper powder coated with silver on the surface. The paste 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 about 100 ° C. for about 30 minutes. As a result, the second via conductor 62 made of the conductive paste is slightly cured, and the adhesive sheets 61a to 61d are completed. As a result, the second via conductor 62 is formed in the via hole 66 (second via conductor forming step). At this time, the tip portion of the second via conductor 62 protrudes from the upper surface of the adhesive organic material sheet 60 (see FIGS. 9 and 11). With such a structure, when the adhesive sheet 61a and the flexible wiring board 51a are joined, the distal end portion of the second via conductor 62 and the first main surface side wiring layer 54 of the flexible wiring board 51a are in pressure contact with each other and bonded. When the sheets 61b and 61c and the flexible wiring boards 51a and 51b are joined, the tip portion of the second via conductor 62 and the second main surface side wiring layer 55 of the flexible wiring boards 51a and 51b are pressed into contact with each other. Further, when the substrate main body 95 is joined to the flexible wiring substrate 51a, the tip end portion of the second via conductor 62 and the lower surface side pad 99 of the substrate main body 95 are in pressure contact. 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.

In addition, the ceramic capacitor 131 in the individual manufacturing process is basically manufactured by a conventionally known method. Specifically, a multilayer body forming step is performed to stack a plurality of dielectric green sheets on which internal electrodes are printed. Then, using a conventionally known laminating apparatus, a pressing force is applied in the sheet stacking direction under a predetermined temperature condition, whereby the respective dielectric green sheets are pressed and integrated. As a result, a green sheet laminate having a thickness of about 1 mm is obtained. In the present embodiment, to set the temperature at the time of stacking crimped 60 ° C. to 80 ° C., has decided to set the pressing force to ^{300kg / cm 2 ~1000kg / cm 2} . Further, the number of stacked layers is set to about 100 to 120 layers. About the number of lamination | stacking, it can change arbitrarily according to the specification etc. which are requested | required.

  Next, by irradiating a laser beam using a laser processing machine, a large number of via holes 143 having a diameter of about 120 μm are formed through the green sheet laminate. Further, using a paste press-fitting and filling device, the via hole 143 is filled with a nickel paste for via conductor to form a via conductor 134.

  Then, the green sheet laminate is degreased and further fired at a predetermined temperature for a predetermined time. As a result, barium titanate and nickel in the paste are simultaneously sintered to form a ceramic sintered body. If the ceramic sintered body is broken, the ceramic capacitor 131 can be obtained.

  Further, the module wiring substrate 91 (substrate body 95) 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.

  Next, an electrical inspection process (individual inspection process) is performed, and electrical inspection is individually performed on the completed flexible wiring boards 51a and 51b, the adhesive sheets 61a to 61d, and the ceramic capacitor 131. At the same time, an electrical inspection is performed on the completed module wiring board 91. The electrical inspection in the present embodiment refers to a general in-circuit test performed using an in-circuit tester, for example. Further, the completed flexible wiring boards 51a and 51b, the adhesive sheets 61a to 61d, the ceramic capacitor 131, and the module wiring board 91 may be individually inspected at this time. At this time, if a defective product is found, the defective product is removed in advance. And after the positioning step (first positioning step, second positioning step) using only the flexible wiring boards 51a and 51b, the adhesive sheets 61a to 61d, the ceramic capacitor 131, and the module wiring board 91 that have passed the electrical inspection and the appearance inspection. Perform the process. Therefore, the probability that the multilayer wiring board structure 10 becomes a defective product is reduced, leading to an improvement in yield.

  In the first positioning step, first, the adhesive sheet 61a, the flexible wiring board 51a, the adhesive sheet 61b, the flexible wiring board 51b, and the adhesive sheet 61c are sequentially stacked on the flat lower jig 101. In addition, the ceramic capacitor 131 is disposed in a portion (in the through holes 132 and 133) that becomes the accommodation space 130 in the stacked portion 12. Next, the flexible wiring boards 51a and 51b and the right side portions of the adhesive sheets 61b and 61c are bent 180 ° upward. Then, the right side portion is brought into contact with the sheet first main surface 64 of the adhesive sheet 61 c and the capacitor upper surface 23 of the ceramic capacitor 131. Furthermore, the adhesive sheet 61d is overlaid on the right side portion bent upward in the flexible wiring board 51a. As a result, the flexible wiring board 51a is positioned between the adhesive sheets 61a and 61b and between the adhesive sheets 61b and 61d. Further, the flexible wiring board 51b is positioned between the adhesive sheets 61b and 61c. Then, the spacer 102 is placed on the lower jig 101. The maximum value of the thickness of the spacer 102 is substantially equal to the height of the laminate composed of the two flexible wiring boards 51a and 51b and the four adhesive sheets 61a to 61d. A plurality of positioning pins 105 protruding from the lower jig 101 are inserted into the spacer 102. For this reason, the position shift to the plane direction of the spacer 102 and a laminated body is prevented. Thereafter, the flat upper jig 104 is placed on the adhesive sheet 61d and the spacer 102 (see FIG. 12). 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. Therefore, the second via conductor 62 protruding from the adhesive sheet 61d comes into contact with the cushion material 103 which is an elastic body. At this time, the cushion material 103 is elastically deformed to follow the uneven shape on the adhesive sheet 61d side. Thereby, a pressing force can be equally applied to the adhesive sheet 61d. 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 (joining 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 flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d are pressed along the stacking direction, and the plasticity of the adhesive sheets 61a to 61d is increased by heat. And flexible wiring board 51a, 51b and the adhesive sheets 61a-61d are joined (thermocompression bonding). At this time, the first main surface side wiring layer 54 of the flexible wiring substrate 51a is in pressure contact with the second via conductor 62 of the adhesive sheet 61a, and the second main surface side wiring layer 55 of the flexible wiring substrate 51a is in contact with the second via conductor 62 of the adhesive sheet 61b. The two via conductors 62 are in pressure contact. Further, the second main surface side wiring layer 55 of the flexible wiring board 51b is in pressure contact with the second via conductor 62 of the adhesive sheet 61c. Therefore, the second via conductor 62, the first via conductor 57, the first main surface side wiring layer 54, and the second main surface side wiring layer 55 are electrically connected to each other, and the stacked portion 12 is formed. That is, since the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d are joined in a vacuum atmosphere, generation of voids due to air entrainment can be effectively suppressed. A ceramic capacitor 131 is embedded in the laminated portion 12.

  Next, a 2nd positioning process and a 2nd joining process are implemented in the following way. 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 51a and the adhesive sheet 61d positioned on the uppermost layer of the laminated portion 12 are placed on the flat lower jig 151. At this time, the adhesive sheet 61d is placed on the upper side. 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 51a. Thereby, the position shift to the plane direction of the flexible wiring board 51a is prevented. Next, the substrate body 95 is mounted on the flexible wiring substrate 51a. At this time, the adhesive sheet 61 d is positioned between the first main surface side wiring layer 54 of the flexible wiring substrate 51 a facing each other and the lower surface side pad 99 of the substrate body 95. Then, the spacer 152 is placed on the lower jig 151. Note that the thickness of the spacer 152 is substantially equal to the height of the substrate body 95. A plurality of positioning pins 155 are inserted through the spacer 152. For this reason, displacement of 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. 13).

  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). Accordingly, the substrate body 95 is pressed toward the flexible wiring substrate 51a, and the plasticity of the adhesive sheet 61d is increased by heat. And the board | substrate body 95 is joined (thermocompression bonding) with respect to the board | substrate 1st main surface 52 side of the flexible wiring board 51a through the adhesive sheet 61d of such a state. At this time, the second via conductor 62 of the adhesive sheet 61d and the lower surface side pad 99 of the substrate body 95 are in pressure contact with each other, and the second via conductor 62 and the first main surface side wiring layer 54 of the flexible wiring substrate 51a are in pressure contact with each other. . Therefore, the conductor pillar 96 of the board body 95 and the first main surface side wiring layer 54 of the flexible wiring board 51a are electrically connected to each other via the second via conductor 62 of the adhesive sheet 61d. That is, since the bonding of the substrate main body 95 to the flexible wiring substrate 51a 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 14 side of the laminated portion 12 to form solder bumps 49. In this way, the solder bumps 49 do not need to get in the way when the first joining step is performed. In addition, when solder bump formation is performed after the first bonding step, the solder bump 49 is unlikely to encounter a high temperature of 260 ° C. or higher, unlike when solder bump formation is performed before the first bonding step. 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.

  However, the solder bumps 49 may be formed at the same time when the adhesive sheet 61a is manufactured, and then the first joining step may be performed. In this way, when the adhesive sheet 61a is inspected in the electrical inspection step, the inspection including the solder bumps 49 can be performed, so that the multilayer wiring board structure 10 is manufactured in a state where the solder bumps 49 are defective. Can be prevented.

  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.

  Thereafter, the IC chip 21 is placed on the terminal connection portion 56 of the stacked portion 12. At this time, the surface connection terminals 22 on the IC chip 21 side and the first main surface side wiring layer 54 on the flexible wiring board 51a side are aligned. Then, a pressing force is applied in the stacking direction (bonding direction) while heating. Accordingly, the IC chip 21 and the adhesive sheet 61d are pressed along the stacking direction, and the plasticity of the adhesive sheet 61d is increased by heat. Then, the lower surface of the IC chip 21 is bonded (thermocompression bonding) onto the sheet first main surface 64 of the adhesive sheet 61d. At this time, the surface connection terminal 22 and the first main surface side wiring layer 54 are electrically connected via the second via conductor 62 of the adhesive sheet 61d. At this stage, a multilayer wiring board structure 10 (so-called system in package: SIP) in which a plurality of functions are integrated and systematized is completed.

  Furthermore, the solder bumps 49 of the laminated portion 12 and the terminals 82 on the mother board 81 side are aligned, and the multilayer wiring board structure 10 is placed on the mother board 81. Then, the solder bumps 49 and the terminals 82 are joined by heating and reflowing the solder bumps 49. As a result, the multilayer wiring board structure 10 is mounted on the mother board 81.

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

  (1) In the multilayer wiring board structure 10 of the present embodiment, since the element mounting area 50 is set on the upper surface 13 of the stacked portion 12, the IC chip 21 mounted in the element mounting area 50 is outside the stacked section 12. Is located. For this reason, the heat generated from the IC chip 21 is easily dissipated to the outside of the laminated portion 12. Therefore, since the plastic deformation of the laminated portion 12 due to the influence of heat is prevented, the multilayer wiring board 11 having high dimensional stability can be obtained. Further, malfunction of the IC chip 21 due to the influence of heat can be prevented.

  In addition, since the laminated portion 12 is partially reinforced by the embedding of the ceramic capacitor 131 having high mechanical strength, the coplanarity of the element mounting region 50 is increased. Therefore, poor connection between the surface connection terminals 22 and the terminal connection portions 56 of the IC chip 21 is less likely to occur, and high connection reliability can be obtained.

  (2) Since the multilayer wiring board structure 10 of the present embodiment includes the module wiring board 91 in addition to the multilayer wiring board 11, the multi-layered wiring board structure 10 can be multifunctional compared to the case where the module wiring board 91 is not provided. . Therefore, it becomes easy to realize one systemized multilayer wiring board structure 10 (so-called system-in-package: SIP), and the added value is also increased.

  (3) The flexible wiring boards 51a and 51b of the present embodiment have conductor patterns (first main surface side wiring layer 54, second main surface side wiring layer) on both the substrate first main surface 52 and the substrate second main surface 53. 55) is formed. For this reason, even if the adhesive sheets 61a to 61d on which no conductor pattern is formed are used, it is possible to configure many circuits inside, and the added value can be increased.

  (4) The adhesive sheets 61a to 61d of the present embodiment are mainly formed of an insulating base material made of a thermoplastic resin (thermoplastic polyimide). Therefore, for example, even if the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d are joined in a state of being displaced from each other, if the adhesive sheets 61a to 61d are heated again, the adhesive sheets 61a from the flexible wiring boards 51a and 51b. ~ 61d can be peeled off. For this reason, the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d can be easily joined again. Similarly, even if the substrate main body 95 is bonded to the flexible wiring substrate 51a in a state of being displaced, the substrate main body 95 can be peeled from the adhesive sheet 61d by heating the adhesive sheet 61d again. For this reason, the board body 95 can be easily joined to the flexible wiring board 51a.

  (5) In the manufacturing method of this embodiment, before forming the laminated portion 12, the flexible wiring boards 51a and 51b, the adhesive sheets 61a to 61d, and the ceramic capacitor 131 are individually manufactured in the individual manufacturing process. The electrical inspection can be performed individually. Therefore, since a defective product can be found and removed in advance before joining, only the flexible wiring boards 51a and 51b, the adhesive sheets 61a to 61d and the ceramic capacitor 131 that have passed the electrical inspection are joined to form the laminated portion 12. can do. Therefore, the probability that the multilayer wiring board 11 becomes a defective product is reduced, leading to an improvement in yield.

  Further, when the bonding process is performed, the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d are bonded, and at the same time, the ceramic capacitor 131 is embedded, so that the multilayer wiring board 11 can be manufactured efficiently.

  (6) In the manufacturing method of the present embodiment, the first bonding step is performed before the IC chip 21 is mounted on the terminal connection portion 56 of the flexible wiring board 51a. 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.

  The ceramic capacitor 131 of the above embodiment has the external terminal (the lower end portion of the via conductor 134) on the capacitor lower surface 24. However, as shown in FIG. 14, the ceramic capacitor 131 may have an external terminal also on the capacitor upper surface 23. In this case, the external terminal (the upper end portion of the via conductor 134) on the capacitor upper surface 23 is connected to the terminal connecting portion via the first via conductor 57 of the flexible wiring boards 51a and 51b and the second via conductor 62 of the adhesive sheets 61b and 61d. 56 is electrically connected. By doing so, the length of the wiring connecting the ceramic capacitor 131 and the element mounting region 50 is shortened, so that the signal speed between the ceramic capacitor 131 and the element mounting region 50 can be increased.

  In the above embodiment, the lower end portion of the via conductor 134 is an external terminal of the ceramic capacitor 131. However, for example, an external terminal electrode that is electrically connected to the via conductor 134 may be formed on the capacitor upper surface 23 and the capacitor lower surface 24, and this external terminal electrode may be used as the external terminal of the ceramic capacitor 131.

  In the above-described embodiment, the ceramic capacitor 131 (rigid base) is embedded in the multilayer portion 12, but as shown in FIG. 15, the glass ceramic wiring substrate 31 (rigid base, wiring substrate) is disposed in the multilayer portion 12. May be buried. In this way, compared to the case where the rigid base does not have a wiring layer, it is possible to configure a circuit therein, and the added value can be increased. Further, since the glass ceramic wiring substrate 31 has extremely high rigidity, the IC chip 21 can be supported more reliably. The glass ceramic wiring board 31 has an upper surface 32 and a lower surface 33 located on the opposite side of the upper surface 32. The glass ceramic wiring board 31 has a structure in which a plurality of ceramic layers 30 and a plurality of wiring layers 37 are alternately stacked. The ceramic layer 30 is formed by firing a green sheet mainly composed of glass and alumina, and the wiring layer 37 is formed mainly of silver or copper. Further, a plurality of via holes 34 penetrating the upper surface 32 and the lower surface 33 are formed in the glass ceramic wiring substrate 31 in a lattice shape. In the via hole 34, a via conductor 35 whose main material is silver or copper is provided. An upper terminal electrode 36 made of silver or copper is provided on the upper end surface of each via conductor 35. On the other hand, the lower end surface of each via conductor 35 is electrically connected to the second via conductor 62 of the adhesive sheet 61b. The glass ceramic wiring board 31 may include passive components such as a ceramic capacitor 131.

  In the above embodiment, the passive component (ceramic capacitor 131) involved in improving the operability of the IC chip 21 is embedded in the stacked unit 12, but the passive component may not be embedded. For example, as shown in FIG. 16, a metal plate 135 (rigid substrate) may be embedded in the stacked portion 12.

  -In the lamination | stacking part 12 of the said embodiment, the adhesive sheets 61a and 61d located in the uppermost layer and the lowest layer may not be. In this case, the connection between the first main surface side wiring layer 54 of the flexible wiring substrate 51 a located in the uppermost layer of the laminated portion 12 and the lower surface side pad 99 of the substrate body 95 is performed by, for example, solder bumps on the lower surface side pad 99. It is performed by providing and reflowing the solder bump. For mounting the multilayer wiring board structure 10 on the mother board 81, solder bumps 49 are provided on the first main surface side wiring layer 54 of the flexible wiring board 51a located at the lowermost layer of the laminated portion 12, and the solder bumps 49 are provided. This is done by reflowing.

  In the above embodiment, the laminated portion 12 is formed by bending the right side portions of the flexible wiring boards 51a and 51b and the adhesive sheets 61b and 61c upward by 180 °. However, for example, as shown in FIG. 17, the laminated portion 12 may be formed without bending the flexible wiring boards 51a and 51b and the adhesive sheets 61b and 61c.

  As shown in FIG. 17, the stacked portion 12 may have a protruding portion 59 that protrudes from the side surface of the stacked portion 12 in the planar direction. And the 1st main surface side wiring layer 54 formed in this overhang | projection part 59 may have the connector connection terminal 71 in the front-end | tip part. With such a structure, it is possible to easily connect to another substrate via the connector connection terminal 71. Further, another structure can be mounted on the first main surface side wiring layer 54 formed on the overhang portion 59. In addition, the multilayer wiring board 11 can be miniaturized because it can be bent and used in the middle of the overhang portion 59. Therefore, even when the space in which the multilayer wiring board 11 is accommodated is narrow, there is a high possibility that the flexible wiring board 51b can be accommodated well by bending it.

  In the above embodiment, the flexible wiring boards 51a and 51b are joined (thermocompression bonding) via one adhesive sheet 61b, and the right and left portions of the flexible wiring board 51b are joined via one adhesive sheet 61c. Were joined (thermocompression bonding). However, the flexible substrates may be joined to each other via two or more adhesive sheets. For example, as shown in FIG. 18, the flexible wiring board 51a located on the lower layer side of the laminated portion 12 and the flexible wiring board 51a located on the upper layer side may be joined via five adhesive sheets 61b.

  In the above embodiment, the laminated portion 12 is formed by joining the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d in a laminated state. That is, the laminated part 12 was formed only by performing the joining process once. However, the laminated portion 12 may be formed by repeating the process of laminating and bonding the flexible wiring boards 51a and 51b and the adhesive sheets 61a to 61d one by one.

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

  (1) A laminate having a first main surface and a second main surface, which is formed by laminating a flexible substrate having a first via conductor and a conductor pattern extending in the substrate plane direction, and a flexible adhesive sheet having a second via conductor. A substantially flat plate-like rigid base is embedded in the laminated portion, and at least one of the first main surface and the second main surface is a region corresponding to the embedded portion of the rigid base. An element mounting area in which a semiconductor circuit element can be mounted is set, and in the element mounting area, a plurality of terminal connection portions to which a plurality of terminals of the semiconductor circuit element can be connected are formed, and the first via conductor, The multilayer wiring board, wherein at least one of the second via conductor and the conductor pattern also serves as the plurality of terminal connection portions.

  (2) A laminated portion having a first main surface and a second main surface, wherein a flexible substrate having a first via conductor and a conductor pattern extending in a plane direction of the substrate and an adhesive sheet having a second via conductor are laminated. A multilayer wiring board comprising: a rigid substrate embedded in the laminated portion; and the adhesive sheet is disposed between the flexible boards to bond the flexible boards to each other, and the flexible board has the first Electrically connecting one via conductor and an external terminal included in the rigid base via the second via conductor, and an element mounting region is set on at least one of the first main surface and the second main surface; A plurality of terminal connection portions are formed in the element mounting region, and at least one of the first via conductor, the second via conductor, and the conductor pattern is Multi-layer wiring board, characterized in that also serves as a plurality of terminal connections.

  (3) A laminated portion having a first main surface and a second main surface, which is formed by laminating a flexible substrate having a first via conductor and a conductor pattern extending in the plane direction of the substrate, and an adhesive sheet having a second via conductor. In the multilayer wiring board, a rigid substrate having a substrate first main surface located on the first main surface side and a substrate second main surface located on the second main surface side is embedded in the stacked portion, The area of the first main surface of the base is set to be not less than 1 and not more than 5 times the area of the element mounting region, and an element mounting region is set on at least one of the first main surface and the second main surface. A plurality of terminal connection portions are formed in the element mounting region, and at least one of the first via conductor, the second via conductor, and the conductor pattern also serves as the plurality of terminal connection portions. Multilayer wiring board characterized by

  (4) A laminated portion having a first main surface and a second main surface, which is formed by laminating a flexible substrate having a first via conductor and a conductor pattern extending in the substrate plane direction, and an adhesive sheet having a second via conductor. In the multilayer wiring board, a rigid substrate made of ceramic whose Young's modulus is set to 0.1 GPa or more and 500 GPa or less is embedded in the laminated portion, and at least one of the first main surface and the second main surface An element mounting area is set, a plurality of terminal connection portions are formed in the element mounting area, and at least one of the first via conductor, the second via conductor, and the conductor pattern is connected to the plurality of terminal connections. A multilayer wiring board characterized by also serving as a part.

  (5) A laminated portion having a first main surface and a second main surface, wherein a flexible substrate having a first via conductor and a conductor pattern extending in the substrate plane direction and an adhesive sheet having a second via conductor are laminated. A rigid substrate made of a ceramic having a thermal expansion coefficient in the plane direction set to 5 ppm / ° C. or more and 13 ppm / ° C. or less is embedded in the laminated portion, and the first main surface and the second An element mounting area is set on at least one of the main surfaces, a plurality of terminal connection portions are formed in the element mounting area, and at least one of the first via conductor, the second via conductor, and the conductor pattern is A multilayer wiring board characterized by also serving as the plurality of terminal connection portions.

1 is a schematic cross-sectional view showing a multilayer wiring board structure including a multilayer wiring board in the present embodiment. The exploded sectional view showing the composition of a multilayer wiring board structure. The expanded sectional view which shows the ceramic capacitor vicinity of a laminated part. Schematic explanatory drawing for demonstrating the connection in the inner layer of a ceramic capacitor. Schematic explanatory drawing for demonstrating the connection in the inner layer of a ceramic capacitor. The exploded sectional view showing the composition of the structure which consists of a flexible wiring board and a substrate main part. 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 2nd via conductor in a via hole in the preparation process of an adhesive sheet. The schematic sectional drawing which shows the process of forming a via hole and a through-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 2nd via conductor 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 an adhesive sheet are joined and a laminated part is formed in the manufacture process of a multilayer wiring board structure. The schematic sectional drawing which shows a mode when a flexible wiring board and a board | substrate main body are mutually joined in the manufacture process of a multilayer wiring board structure. The schematic sectional drawing which shows the multilayer wiring board structure in other embodiment. The schematic sectional drawing which shows the multilayer wiring board structure in other embodiment. The schematic sectional drawing which shows the multilayer wiring board structure in other embodiment. The schematic sectional drawing which shows the multilayer wiring board structure in other embodiment. The schematic sectional drawing which shows the multilayer wiring board structure in other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Multilayer wiring board structure 11 ... Multilayer wiring board 12 ... Laminated | stacking part 13 ... Upper surface 14 as 1st main surface ... Lower surface 21 as 2nd main surface ... IC chip 23 as an active element ... As base | substrate 1st main surface Capacitor upper surface 24... Capacitor lower surface 31 as a substrate second main surface... Rigid substrate and glass ceramic wiring substrate 50 as a wiring substrate... Device mounting regions 51 a and 51 b. Flexible wiring substrate 54 as a flexible substrate. 1 main surface side wiring layer 55 ... 2nd main surface side conductor layer 56 as a conductor pattern ... terminal connection part 57 ... 1st via conductor 61a, 61b, 61c, 61d ... adhesive sheet 62 ... 2nd via conductor as a via conductor 91 ... Module wiring board 131 as a functional module ... Rigid base and ceramic capacitor 135 as a passive component ... Metal plate as Gide base

Claims (7)

A flexible substrate having a first via conductor and a conductor pattern extending in a plane direction of the substrate and an adhesive sheet having a second via conductor are alternately laminated, and includes a laminated portion having a first main surface and a second main surface. A multilayer wiring board,
A rigid base is embedded in the laminated portion,
In the region directly above the contact Keru the rigid substrate to the first main surface, the element mounting region on which the IC chip is an active element is mounted is set,
A plurality of terminal connection portions are formed in the element mounting region,
At least one of the first via conductor, the second via conductor, and the conductor pattern also serves as the plurality of terminal connection portions ,
The rigid base includes a base first main surface located on the first main surface side and a base second main surface located on the second main surface side, and the base first main surface and the base second main surface. A ceramic capacitor which has a plurality of external terminals on both sides and has a structure in which ceramic dielectric layers and internal electrode layers are alternately stacked, and is a passive component involved in improving the operability of the IC chip. ,
The area of the base first main surface is set larger than the area of the element mounting region,
The plurality of external terminals on the first main surface of the base are electrically connected to the plurality of terminal connection portions via at least one of the first via conductor and the second via conductor,
The plurality of external terminals on the second main surface of the base is electrically connected to the plurality of terminals on the second main surface via at least one of the first via conductor and the second via conductor. A multilayer wiring board characterized by being connected . 2. The multilayer wiring board according to claim 1, wherein a part of the flexible substrate is bent and laminated on the adhesive sheet positioned on an upper layer side in the laminated portion. The flexible substrate is mainly constituted by a non-thermoplastic resin, the adhesive sheet, a multilayer wiring board according to claim 1 or 2, characterized by being composed of a thermoplastic resin as a main component. A multilayer wiring board comprising a plurality of adhesive sheets having at least one of via conductors and a conductor pattern extending in a sheet plane direction, and comprising a laminated portion having a first main surface and a second main surface,
A rigid base is embedded in the laminated portion,
In the region directly above the contact Keru the rigid substrate to the first main surface, the element mounting region on which the IC chip is an active element is mounted is set,
A plurality of terminal connection portions are formed in the element mounting region,
At least one of the via conductor and the conductor pattern also serves as the plurality of terminal connection portions ,
The rigid base includes a base first main surface located on the first main surface side and a base second main surface located on the second main surface side, and the base first main surface and the base second main surface. A ceramic capacitor which has a plurality of external terminals on both sides and has a structure in which ceramic dielectric layers and internal electrode layers are alternately stacked, and is a passive component involved in improving the operability of the IC chip. ,
The area of the base first main surface is set larger than the area of the element mounting region,
The plurality of external terminals on the first main surface of the base are electrically connected to the plurality of terminal connection portions via the via conductors,
The plurality of external terminals on the second main surface of the base body are electrically connected to the plurality of terminals on the second main surface via the via conductors. Multilayer wiring board. Multilayer wiring board and a multilayer wiring board structure is characterized in that a functional module which is bonded to a portion of the multilayer wiring board according to any one of claims 1 to 4. A method for manufacturing a multilayer wiring board according to any one of claims 1 to 3 ,
An individual production step of individually producing the flexible substrate, the adhesive sheet, and the rigid base;
The flexible substrate and the adhesive sheet are laminated and bonded to form a laminated portion, and at that time, the second via conductor is electrically connected to at least one of the first via conductor and the conductor pattern. And a bonding step of burying the rigid base in the laminated portion. A method for manufacturing a multilayer wiring board, comprising: It is a manufacturing method of the multilayer wiring board according to claim 4 ,
An individual production step of individually producing the plurality of adhesive sheets and the rigid substrate;
A lamination step of laminating and bonding the plurality of adhesive sheets to form a laminated portion, electrically connecting the via conductors at that time, and embedding the rigid base in the laminated portion. A method for producing a multilayer wiring board, comprising:

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