JP5122846B2 - Wiring board with built-in capacitor - Google Patents

Description

  The present invention relates to a wiring board with a built-in capacitor having a structure in which a wiring laminated portion is formed on the surface of a core substrate, in which a capacitor is accommodated.

  In recent years, semiconductor integrated circuit elements (IC chips) used as computer microprocessors (CPUs) and the like have become increasingly faster and more functional, with the accompanying increase in the number of terminals and the narrower pitch between terminals. There is a tendency. In general, a large number of terminals are densely arranged on the bottom surface of an IC chip, and such a terminal group is connected to a terminal group on the motherboard side in the form of a flip chip. However, it is difficult to connect the IC chip directly on the mother board because there is a large difference in the pitch between the terminals on the IC chip side terminal group and the mother board side terminal group. For this reason, a method is usually employed in which a package is formed by mounting an IC chip on a wiring board, and the package is mounted on a motherboard.

  Recently, there has been a strong demand for a system capable of realizing higher performance than a package having a structure with only one microprocessor chip. For example, a multi-chip module (MCM) suitable for a server computer or the like is used. ) Has been proposed. The MCM is an electronic component formed by mounting a plurality of microprocessor chips on a relay substrate. As one form of the MCM, a plurality of microprocessor chips (arithmetic processing circuit units) arranged on the outer peripheral part and a memory chip (shared circuit unit) arranged in the central part and commonly used by the microprocessor chips Has been proposed on the relay board.

Further, it has been proposed that a wiring board constituting this type of package incorporates a capacitor (also referred to as a “capacitor”) in order to reduce switching noise such as an IC chip. As an example, a wiring board in which a capacitor is housed in a housing hole of a core substrate made of a polymer material and a buildup layer is formed on the front surface and the back surface of the core substrate has been conventionally proposed (for example, see Patent Document 1). ). As the capacitor, a via array type ceramic capacitor or the like is used.
Japanese Patent Laying-Open No. 2005-39243 (FIG. 4 etc.)

  By the way, since the memory chip described above consumes a large amount of power, when an MCM is to be mounted on the wiring board described in Patent Document 1, it is necessary to provide a supply path for supplying a large current in the wiring board. There is. However, the ceramic capacitor is disposed as close to the MCM as possible (specifically, directly below the MCM) in order to effectively reduce the switching noise. Further, the ceramic capacitor is formed as large as possible in order to reduce switching noise, and the capacity is increased.

  Therefore, in order to supply a large current to the memory chip in the central portion of the MCM, for example, a configuration as shown in FIGS. 20 and 21 can be considered. That is, a ceramic capacitor 201 is provided for each microprocessor chip 203 of the MCM 202, the ceramic capacitors 201 are spaced apart, and a current supply conductor 205 is disposed below the memory chip 204 of the MCM 202. However, since the mounting area of the ceramic capacitor 201 is reduced by the amount of the current supply conductor 205, the ceramic capacitor 201 cannot be formed large and it is difficult to increase the capacity. Further, since the MCM 202 cannot be reliably supported by the ceramic capacitor 201 having high rigidity and a low coefficient of thermal expansion, mechanical stress such as thermal stress is applied to the MCM 202, and cracks and poor connection are likely to occur in the MCM 202.

  In order to solve the above problem, it is conceivable to supply a large current to the memory chip 204 by bypassing the outside of the mounting area of each ceramic capacitor 201 without arranging the ceramic capacitors 201 apart from each other. However, since the supply path of a large current becomes long, the resistance becomes large.

  Accordingly, it is conceivable to supply a large current to the memory chip 204 via the via conductor 206 in the ceramic capacitor 201 without arranging the ceramic capacitors 201 apart from each other. However, since the via conductor 206 in the capacitor in the ceramic capacitor 201 is usually formed of a metal material (such as nickel) that is not very conductive, there is a demand to avoid using it as a supply path for a large current. is there.

  The present invention has been made in view of the above problems, and its object is to supply a large current to an electronic component, increase the capacity of a capacitor, and reduce mechanical stress on the electronic component. Accordingly, it is an object of the present invention to provide a capacitor built-in wiring board capable of improving reliability.

And as a means for solving the above-mentioned problem, it has a core substrate having a core main surface and a core back surface, and at least a housing hole opened on the core main surface side, and a capacitor main surface and a capacitor back surface And a capacitor plate housed in the housing hole in a state in which the core main surface and the capacitor main surface are directed to the same side, having a modified plate shape having a through-hole penetrating the capacitor main surface and the capacitor back surface, A conductor forming portion is formed in which a current supply conductor for conducting the core back surface side and the core main surface side is formed, and is disposed so as to be surrounded by the capacitor in the through hole of the capacitor; an interlayer insulating layer; and a conductor layer Are stacked on the main surface of the core, and a component mounting area on which an electronic component can be mounted is set on the surface, and the current supply conductor is electrically connected to the component mounting area. The first connection terminal portion is arranged which is continued, and a a first connection terminal portion is disposed a plurality of second connecting terminal portions across the wiring layered part, the capacitor, forms a generally rectangular plan view shape A via array type ceramic capacitor having a plurality of via conductors in the capacitor, wherein the conductor forming portion is configured separately from the core substrate, and the through hole and the conductor forming portion are viewed in plan view. There is a wiring board with a built-in capacitor, characterized by having a shape without corners .

  Therefore, according to the capacitor built-in wiring board described in the above means, since the through hole exists in the capacitor, the conductor forming portion can be arranged without difficulty in the through hole without dividing or reducing the capacitor. Therefore, a large current can be supplied to the electronic component mounted in the component mounting region where the first connection terminal portion is disposed via the current supply conductor formed in the conductor formation portion and the first connection terminal portion. it can. In addition, regardless of the presence of the conductor forming portion, it is possible to form a capacitor with a large area on the main surface of the capacitor, which increases the capacity of the capacitor and ensures that the electronic component mounted in the component mounting area is secured by the capacitor. Supported by Therefore, in the component mounting region, the wiring laminated portion is not easily deformed, so that mechanical stress applied to the electronic component can be reduced, and the reliability of the wiring board with a built-in capacitor can be improved.

  The core substrate constituting the capacitor built-in wiring substrate is formed in a plate shape having, for example, a core main surface and a core back surface located on the opposite side, and has a plurality of receiving holes for receiving capacitors. . These accommodation holes may be non-through holes that open only on the core main surface side, or may be through holes that open on both the core main surface side and the core back surface side. In addition, the capacitor may be accommodated in the accommodation hole in a completely embedded state, or may be accommodated in the accommodation hole in a state in which a part protrudes from the opening of the accommodation hole.

  A material for forming the core substrate is not particularly limited, but a preferable core substrate is mainly formed of a polymer material. Specific examples of the polymer material for forming the core substrate include, for example, EP resin (epoxy resin), PI resin (polyimide resin), BT resin (bismaleimide / triazine resin), PPE resin (polyphenylene ether resin), etc. There is. 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 capacitor constituting the capacitor-embedded wiring board has an odd-shaped plate shape having a capacitor main surface and a capacitor side surface and a through-hole penetrating the capacitor main surface and the capacitor back surface. Note that the shape of the capacitor in a plan view is preferably a substantially polygonal shape in a plan view having a plurality of sides and a through hole. Examples of the substantially polygonal shape in plan view include a substantially rectangular shape in plan view, a substantially triangular shape in plan view, and a substantially hexagonal shape in plan view. Preferably there is. Here, “substantially rectangular shape in plan view” does not mean a complete rectangular shape in plan view, but has a shape with chamfered corners and a part of a side having a through hole. It includes the shape that is.

  Examples of the cross-sectional shape of the through-hole include a circular cross-section, a substantially rectangular cross-section, a substantially triangular cross-section, and a substantially hexagonal cross-section, and a cross-sectional circular shape is preferable. In this case, since there is no corner portion in the through hole, stress concentration on a part (corner portion) of the through hole due to a temperature change can be alleviated, so that generation of cracks in the through hole can be prevented. Further, since the opening area of the through hole can be easily reduced, the area of the capacitor main surface can be easily increased, and the capacity of the capacitor can be increased. Note that the through hole may or may not be connected to the region outside the capacitor side surface through the notch. In the latter case, the mechanical strength of the capacitor is higher than that in the former, and the capacitor is less likely to warp.

  The position of the through hole is not particularly limited, but it is preferably arranged at the center of the capacitor rather than at the outer periphery of the capacitor. Further, only one through hole may be provided, or two or more through holes may be provided. When two or more through holes are provided, the diameter of the through hole is preferably smaller than when only one through hole is provided.

  The diameter of the through hole is preferably slightly larger than the diameter of the conductor forming portion. The diameter of the through hole is preferably set to 20% or more and 50% or less of the length of the shortest side among the sides constituting the capacitor main surface. If the diameter of the through hole is less than 20% of the length of the shortest side constituting the capacitor main surface, the diameter of the current supply conductor formed in the conductor forming portion becomes too small. It becomes difficult to flow a large current through the current supply conductor. On the other hand, if the diameter of the through hole is larger than 50% of the length of the shortest side constituting the capacitor main surface, the mechanical strength of the capacitor is lowered and the capacitor is likely to warp. Further, when the capacitor has a plurality of via conductors in the capacitor, the diameter of the through hole is preferably larger than the diameter of the via conductor in the capacitor, for example, set to 5 times or more the diameter of the via conductor in the capacitor. Is good.

  Examples of suitable capacitors include a chip capacitor and a structure in which a plurality of internal electrode layers are stacked via a dielectric layer, and a plurality of vias in the capacitor connected to the plurality of internal electrode layers. Examples thereof include a capacitor having a conductor and a plurality of surface layer electrodes connected to at least an end portion on the capacitor main surface side of the plurality of via conductors in the capacitor. It is preferable that the capacitor is a via array type capacitor having a plurality of via conductors in a capacitor, and the plurality of via conductors in the capacitor are arranged in an array as a whole. With such a structure, the inductance of the capacitor can be reduced, and noise absorption and voltage stabilization can be achieved. In addition, it is easy to reduce the size of the entire capacitor, and it is also easy to reduce the size of the entire wiring board with a built-in capacitor. Moreover, a high electrostatic capacity is easily achieved for a small amount, and a more stable power supply can be achieved.

  Examples of the dielectric layer constituting the capacitor include a ceramic dielectric layer, a resin dielectric layer, and a dielectric layer made of a ceramic-resin composite material. As the ceramic dielectric layer, a sintered body of a high-temperature fired ceramic such as alumina, aluminum nitride, boron nitride, silicon carbide, silicon nitride, or the like is preferably used, and for borosilicate glass or lead borosilicate glass. A sintered body of low-temperature fired ceramic such as glass ceramic to which an inorganic ceramic filler such as alumina is added is preferably used. In this case, it is also preferable to use a sintered body of a dielectric ceramic such as barium titanate, lead titanate, or strontium titanate depending on the application. When a dielectric ceramic sintered body is used, a capacitor having a large capacitance can be easily realized. Further, as the resin dielectric layer, an epoxy resin, a resin such as tetrafluoroethylene resin (PTFE) containing an adhesive is preferably used. Furthermore, as the dielectric layer made of the ceramic-resin composite material, barium titanate, lead titanate, strontium titanate or the like is preferably used as the ceramic, and as the resin material, epoxy resin, phenol resin, urethane resin, Thermosetting resins such as silicone resin, polyimide resin, unsaturated polyester, thermoplastic resin such as polycarbonate resin, acrylic resin, polyacetal resin, polypropylene resin, and latex such as nitrile butadiene rubber, styrene butadiene rubber, and fluoro rubber are suitable. Used for.

  The internal electrode layer, the capacitor via conductor, and the surface electrode are not particularly limited. For example, when the dielectric layer is a ceramic dielectric layer, it is preferably a metallized conductor. The metallized conductor is formed by applying a conductive paste containing metal powder by a conventionally well-known method, for example, a metallized printing method, followed by baking. When the metallized conductor and the ceramic dielectric layer are formed by the co-firing method, the metal powder in the metallized conductor needs to have a melting point higher than the firing temperature of the ceramic dielectric layer. For example, when the ceramic dielectric layer is made of a so-called high-temperature fired ceramic (for example, alumina or the like), nickel (Ni), tungsten (W), molybdenum (Mo), manganese (Mn), or the like is used as the metal powder in the metallized conductor. And their alloys can be selected. When the ceramic dielectric layer is made of a so-called low-temperature fired ceramic (for example, glass ceramic), copper (Cu) or silver (Ag) or an alloy thereof can be selected as the metal powder in the metallized conductor.

  The conductor forming portion constituting the wiring board with a built-in capacitor is arranged so that a current supply conductor for conducting the core back surface side and the core main surface side is formed and is surrounded by the capacitor in the through hole of the capacitor Has been. The conductor forming portion may be completely surrounded by the capacitor in the through hole of the capacitor, or may not be completely surrounded. Although the material which forms a conductor formation part is not specifically limited, A preferable conductor formation part is mainly formed of a polymeric material. Specific examples of the polymer material for forming the conductor forming portion include, for example, an epoxy resin, a polyimide resin, a bismaleimide / triazine resin, a polyphenylene ether resin, and the like. In addition, composite materials of these resins and glass fibers (glass woven fabric or glass nonwoven fabric) or organic fibers such as polyamide fibers may be used. In addition, it is preferable that a conductor formation part is formed with the same material as a core board | substrate. According to this configuration, it is not necessary to prepare a material different from the material for forming the core substrate when forming the conductor forming portion, so that the capacitor built-in wiring substrate can be manufactured at low cost. Further, it becomes easy to form the conductor forming portion as a part of the core substrate.

  The conductor forming portion may be a part of the core substrate, or may be configured separately from the core substrate. If the conductor forming portion is a part of the core substrate, it is not necessary to prepare a material different from the material forming the core substrate in forming the conductor forming portion. It can be manufactured at low cost. On the other hand, if the conductor forming portion is configured separately from the core substrate, the configuration of the conductor forming portion can be made completely different from that of the core substrate. Becomes higher.

  The material for forming the current supply conductor is not particularly limited. For example, copper, copper alloy, nickel, nickel alloy, tin, tin alloy, conductive resin paste, and the like are suitable. As a method for forming a current supply conductor, a plating method is preferable because it is simple and low in cost. However, in addition to the plating method, it is also possible to employ a technique such as sputtering, CVD, or vacuum deposition. In addition, when a conductive resin paste is used as the material for forming the current supply conductor, a method such as filling in holes that are open on both the core main surface side and the core back surface side is suitable. Used.

  The current supply conductor is preferably formed using a metal material having higher conductivity than the plurality of via conductors in the capacitor. If the current supply conductor is made of a metal material having the same conductivity as the via conductor in the capacitor, or a metal material having a lower conductivity than the via conductor in the capacitor, instead of the via conductor in the capacitor The significance (improvement of conductivity) of using the current supply conductor as a large current supply path is lost. When the via conductor in the capacitor is formed using, for example, nickel, it is preferable to use copper, silver, or the like, which is a metal material having a higher conductor than nickel, as the metal material forming the current supply conductor. In particular, it is more preferable to use copper which is a low-cost metal material.

  The current supply conductor preferably does not constitute a signal wiring for sending a signal to the electronic component. In this way, since only wiring for flowing current can be formed in the conductor forming portion, a large number of conductors for supplying current (or a large diameter) are provided in the conductor forming portion while avoiding an increase in size of the conductor forming portion. Can be formed. If the current supply conductor constitutes the signal wiring, the current supply conductor (signal wiring) and the capacitor are arranged close to each other. In this case, the electromagnetic wave generated from the signal wiring is taken as noise into the conductor of the capacitor, and noise disturbance may occur. As a result, there is a concern that proper power supply may be hindered. In addition, noise disturbance may occur when electromagnetic waves generated from the conductor of the capacitor are taken into the signal wiring as noise.

  The wiring laminated portion constituting the capacitor built-in wiring board is formed by laminating an interlayer insulating layer and a conductor layer mainly composed of a polymer material, and a component mounting area on which an electronic component can be mounted is set on the surface. A first connection terminal portion electrically connected to the current supply conductor is disposed in the mounting region, and a plurality of second connection terminal portions are disposed with the first connection terminal portion interposed therebetween. In addition, although there is a large difference in the pitch between terminals between the terminal group on the electronic component side and the terminal group on the capacitor side, the electronic component and the capacitor can be connected via a plurality of second connection terminal portions by providing a wiring laminated portion. Easy to connect. Moreover, although the wiring laminated part is formed only on the core main surface, a laminated part having the same structure as the wiring laminated part may be formed on the core back surface. With this configuration, an electric circuit can be formed not only in the wiring laminated portion formed on the core main surface but also in the laminated portion formed on the back surface of the core. Can be achieved.

  It is preferable that a current supply connection pad having a diameter larger than that of the current supply conductor is provided at an end of the current supply conductor. By doing so, it is possible to achieve a reliable connection between the current supply conductor and the first connection terminal portion as compared with the case where the current supply conductor and the first connection terminal portion are directly connected. Further, since the diameter of the current supply connection pad is larger than the diameter of the current supply conductor, the resistance of the current supply path including the current supply conductor and the first connection terminal portion can be reduced. Furthermore, since the diameter of the current supply connection pad is larger than the diameter of the current supply conductor, when forming a via conductor on the current supply connection pad, even if there is a slight error in the formation position of the via conductor, The current supply connection pad and the via conductor can be reliably connected.

  The interlayer insulating layer can be appropriately selected in consideration of insulation, heat resistance, moisture resistance, and the like. Preferred examples of the polymer material for forming the interlayer insulating layer include thermosetting resins such as epoxy resin, phenol resin, urethane resin, silicone resin, polyimide resin, polycarbonate resin, acrylic resin, polyacetal resin, polypropylene resin, etc. And other thermoplastic resins. In addition, composite materials of these resins and organic fibers such as glass fibers (glass woven fabrics and glass nonwoven fabrics) and polyamide fibers, or three-dimensional network fluorine-based resin base materials such as continuous porous PTFE, epoxy resins, etc. A resin-resin composite material impregnated with a thermosetting resin may be used.

  Although it does not specifically limit as a material which forms the said conductor layer, For example, use of copper, a copper alloy, nickel, a nickel alloy, tin, a tin alloy, the resin paste which has electroconductivity, etc. is suitable. Further, the material for forming the first connection terminal portion, the second connection terminal portion, and the current supply connection pad is not particularly limited, but it is preferable to use the same material as that for forming the conductor layer. . In this way, the first connection terminal portion, the second connection terminal portion, and the current supply connection pad can be formed simultaneously with the formation of the wiring laminated portion. In particular, it is preferable to use low-resistance copper as a material for forming the conductor layer, the first connection terminal portion, the second connection terminal portion, and the current supply connection pad.

  The first connection terminal portion (and the current supply connection pad) is formed using a metal material having the same conductivity as the current supply conductor or a metal material having higher conductivity than the current supply conductor. It is preferable. If the first connection terminal portion (and the current supply connection pad) is formed using a metal material having lower conductivity than the current supply conductor, the current supply conductor (and the current supply connection pad). ) Or the current supply path formed by the first connection terminal portion becomes high, and a large current cannot be efficiently supplied to the electronic component.

  Examples of the electronic component include a semiconductor integrated circuit element (IC chip) used as a microprocessor of a computer, a multi-chip module (MCM) in which a plurality of microprocessor chips are mounted on a relay substrate, and a semiconductor manufacturing process. MEMS (Micro Electro Mechanical Systems) element manufactured by 1). As one mode of the MCM, a plurality of microprocessor chips (arithmetic processing circuit units) and a memory chip (shared circuit unit) that require a larger current supply than the plurality of microprocessor chips and are commonly used by the microprocessor chips. ) On the relay board.

  Note that the above-described electronic component is flip-chip mounted on the component mounting area, for example. The “component mounting area” refers to an area where terminal pad groups are arranged on the surface of the wiring laminated portion.

  Further, the plurality of second connection terminal portions are electrically connected to a plurality of arithmetic processing circuit portions included in the electronic component, respectively, and the first connection terminal portion is shared by the plurality of arithmetic processing circuit portions. It is preferable to be electrically connected to a shared circuit section that is used in the above and requires a larger current supply than the plurality of arithmetic processing circuit sections. If it does in this way, an arithmetic processing circuit part can be reliably connected with respect to a capacitor via the 2nd connecting terminal part. In addition, the shared circuit portion can be reliably connected to the current supply conductor via the first connection terminal portion.

  Hereinafter, an embodiment embodying a wiring board with a built-in capacitor according to the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, a capacitor built-in wiring board (hereinafter referred to as “wiring board”) 10 of this embodiment is a wiring board for mounting electronic components. The wiring substrate 10 includes a substantially rectangular plate-shaped core substrate 11, a first buildup layer 31 (wiring laminated portion) formed on the core main surface 12 (upper surface in FIG. 1) of the core substrate 11, and the core substrate 11. The second buildup layer 32 is formed on the core back surface 13 (the lower surface in FIG. 1).

  The first buildup layer 31 formed on the core main surface 12 of the core substrate 11 is composed of two resin insulating layers 33 and 35 (so-called interlayer insulating layer) made of thermosetting resin (epoxy resin) and copper. The conductive layers 42 are alternately laminated. Via conductors 43 are formed at a plurality of locations in the second resin insulating layer 35. A portion serving as the lower end of each via conductor 43 is connected to the conductor layer 42 formed on the surface of the resin insulating layer 33, and a portion serving as the upper end of each via conductor 43 is disposed on the surface of the resin insulating layer 35. It is connected to the formed conductor layer 42. In addition, terminal pads 44 are formed in an array at a plurality of locations on the surface of the second resin insulating layer 35. Further, the surface of the resin insulating layer 35 is almost entirely covered with a solder resist 37. An opening 46 for exposing the terminal pad 44 is formed at a predetermined position of the solder resist 37. A plurality of solder bumps 45 are provided on the surface of the terminal pad 44. Each solder bump 45 is electrically connected to a surface connection terminal 22 of a multi-chip module (hereinafter referred to as “MCM”) 21 which is an electronic component. Note that an area including the terminal pads 44 and the solder bumps 45 is a component mounting area 23 in which the MCM 21 can be mounted. The component mounting area 23 is set on the surface 39 of the first buildup layer 31.

  As shown in FIGS. 1 to 3 and the like, the MCM 21 of the present embodiment has a substantially rectangular plate shape in plan view of 25 mm length × 28 mm width. The MCM 21 has a structure in which two microprocessor chips 24 and 25 (arithmetic processing circuit unit) and one memory chip 26 (shared circuit unit) are mounted on a relay board 27 having a rectangular flat plate shape. . The relay substrate 27 includes a plurality of surface connection terminals 22 on the lower surface, a first conductor portion (not shown) that connects the surface connection terminals 22 and the memory chip 26, the surface connection terminals 22, and the microprocessor chips 24 and 25. And a second conductor portion (not shown) for connecting the two. Each of the microprocessor chips 24 and 25 has a rectangular flat plate shape, and is arranged so as to sandwich the memory chip 26 at the outer peripheral portion of the relay substrate 27. Each of the microprocessor chips 24 and 25 is a circuit unit for performing various arithmetic processes. On the other hand, the memory chip 26 has a rectangular flat plate shape and is arranged at the center of the relay substrate 27. The memory chip 26 is a circuit unit that is used jointly by the microprocessor chips 24 and 25 in order to store the calculation processing results in the microprocessor chips 24 and 25. The memory chip 26 needs to be supplied with a larger current than the microprocessor chips 24 and 25.

  As shown in FIG. 1, the second buildup layer 32 formed on the core back surface 13 of the core substrate 11 has substantially the same structure as the first buildup layer 31 described above. That is, the second buildup layer 32 has a structure in which two resin insulating layers 34 and 36 made of thermosetting resin (epoxy resin) and conductor layers 42 are alternately stacked. Via conductors 47 are formed at a plurality of locations in the first resin insulating layer 34. The lower end of each via conductor 47 is connected to a conductor layer 42 formed on the surface of the resin insulating layer 34. Via conductors 43 are formed at a plurality of locations in the second resin insulation layer 36, and conductors are provided via via conductors 43 at locations that are lower ends of the via conductors 43 on the lower surface of the resin insulation layer 36. PGA pads 48 electrically connected to the layer 42 are formed in a lattice shape. The lower surface of the resin insulating layer 36 is almost entirely covered with a solder resist 38. An opening 40 for exposing the PGA pad 48 is formed at a predetermined portion of the solder resist 38. On the surface of the PGA pad 48, a plurality of pins 49 for electrical connection with a mother board (not shown) are connected by soldering. Then, the wiring board 10 shown in FIG. 1 is mounted on a mother board (not shown) by each pin 49.

  As shown in FIGS. 1 and 4, the core substrate 11 of the present embodiment has a substantially rectangular plate shape in plan view of 50.0 mm in length × 50.0 mm in width × 1.0 mm in thickness. The core substrate 11 includes a base material 161 made of glass epoxy, a sub-base material 164 formed on an upper surface and a lower surface of the base material 161 and made of an epoxy resin to which an inorganic filler such as silica filler is added, and an upper surface of the base material 161. And a conductor layer 163 made of copper and formed on the lower surface. The core substrate 11 is formed with a plurality of through-hole conductors 16 made of copper so as to penetrate the core main surface 12, the core back surface 13, and the conductor layer 163. The through-hole conductor 16 connects and conducts the core main surface 12 side and the core back surface 13 side of the core substrate 11 and is electrically connected to the conductor layer 163. The inside of the through-hole conductor 16 is filled with a closing body 17 such as an epoxy resin. Further, a conductor layer 41 made of copper is patterned on the core main surface 12 and the core back surface 13 of the core substrate 11, and each conductor layer 41 is electrically connected to the through-hole conductor 16.

  As shown in FIGS. 1 and 4, a conductor forming portion 14 is disposed at the center of the core substrate 11. The conductor forming portion 14 of the present embodiment has a shape with no corners in plan view, and specifically has a circular shape in plan view. In addition, it is preferable that the diameter of the conductor formation part 14 is 5.0 mm or more and 15 mm or less, and is set to 11.0 mm in this embodiment. Moreover, the thickness of the conductor formation part 14 is set to 1.0 mm. The conductor forming portion 14 is configured separately from the core substrate 11, and includes a first base material 165 made of the same material (glass epoxy) as the base material 161 and the same material (silica filler or the like) as the sub base material 164. And a second base material 166 made of an epoxy resin to which an inorganic filler is added. In addition, a plurality of (four in this embodiment) current supply conductors 15 made of copper are formed in the conductor forming portion 14 so as to penetrate the core main surface 12 and the core back surface 13. The current supply conductor 15 is a through-hole conductor that connects and connects the core main surface 12 side and the core back surface 13 side of the core substrate 11. Note that the inside of the current supply conductor 15 is filled with a closing body 18 such as an epoxy resin.

  As shown in FIG. 1 and FIG. 4, current supply connection pads 19 made of copper project from the main surface 167 and the back surface 168 of the conductor forming portion 14. The current supply connection pad 19 provided on the main surface 167 of the conductor forming portion 14 is directly connected to the end portion on the main surface 167 side of the current supply conductor 15, and is connected to the back surface 168 of the conductor forming portion 14. The provided current supply connection pad 19 is directly connected to the end of the current supply conductor 15 on the back surface 168 side. The current supply connection pad 19 has a disk shape, and the center axis of the current supply connection pad 19 coincides with the center of the current supply conductor 15. The diameter of the current supply connection pad 19 is set larger than the diameter of the current supply conductor 15 (about 100 μm), and is set to about 500 μm in this embodiment. The thickness of the current supply connection pad 19 is set to 50 μm, for example, and is equal to the thickness of the conductor layer 41. The current supply connection pad 19 provided on the main surface 167 side of the conductor forming portion 14 is connected to the via conductor 47 formed in the resin insulating layer 33 and provided on the back surface 168 side of the conductor forming portion 14. The current supply connection pad 19 is connected to a via conductor 47 formed in the resin insulation layer 34.

  As shown in FIGS. 1 and 4, the core substrate 11 is formed with an accommodation hole 90 that opens at the center portion of the core main surface 12 and the center portion of the core back surface 13. That is, each accommodation hole 90 is a through hole having a substantially rectangular shape in plan view. And in the accommodation hole 90, the ceramic capacitor 101 shown in FIGS. 5-8 etc. is accommodated in the embedded state. The ceramic capacitor 101 is accommodated with the capacitor main surface 102 facing the same side as the core main surface 12 of the core substrate 11. The ceramic capacitor 101 of this embodiment has a flat plate shape of 25.0 mm long × 25.0 mm wide × 0.8 mm thick. The ceramic capacitor 101 is arranged in a region immediately below the component mounting region 23 in the core substrate 11. The area of the component mounting region 23 (the area of the surface on which the surface connection terminals 22 are formed in the MCM 21) is set to be substantially equal to the area of the capacitor main surface 102 of the ceramic capacitor 101. Accordingly, when viewed from the thickness direction of the ceramic capacitor 101, the component mounting region 23 is located in the capacitor main surface 102 of the ceramic capacitor 101. More specifically, as shown in FIG. 4, the microprocessor chips 24 and 25 of the MCM 21 are located in the capacitor main surface 102 of the ceramic capacitor 101. The memory chip 26 of the MCM 21 is disposed above the main surface 167 of the conductor forming portion 14 and is disposed so as to straddle the main surface 167 of the conductor forming portion 14 and the capacitor main surface 102 of the ceramic capacitor 101. ing.

  As shown in FIGS. 1 and 4, the gap between the inner surface of the accommodation hole 90 and the capacitor side surface 106 of the ceramic capacitor 101, and the gap between the inner wall surface of the through hole 107 of the ceramic capacitor 101 and the side surface of the conductor forming portion 14. Is filled with a filler 33 a which is a part of the lowermost resin insulating layer 33 in contact with the core main surface 12. The filler 33 a has a function of fixing the ceramic capacitor 101 and the conductor forming portion 14 to the core substrate 11. The ceramic capacitor 101 has chamfered portions with chamfering dimensions of 0.55 mm or more (in this embodiment, chamfering dimensions of 0.6 mm) at the four corners. Thereby, when the filler 33a is deformed due to a temperature change, stress concentration on the corners of the ceramic capacitor 101 can be alleviated, so that the occurrence of cracks in the filler 33a can be prevented.

  As shown in FIGS. 5 to 8 and the like, the ceramic capacitor 101 has an odd-shaped plate shape having a through-hole 107 having a circular cross section penetrating the capacitor main surface 102 and the capacitor back surface 103. The through hole 107 is arranged at the center of the ceramic capacitor 101. In the present embodiment, the diameter of the through hole 107 is set to 15.0 mm. That is, the diameter of the through hole 107 is slightly larger than the diameter of the conductor forming portion 14. The diameter of the through-hole 107 is set to about 60% of the length of the shortest side (the horizontal length of the ceramic capacitor 101) among the sides constituting the capacitor main surface 102. Further, the diameter of the through hole 107 is set to 150 times the diameter (100 μm) of the via conductors 131 and 132 in the capacitor. A conductor forming portion 14 is accommodated in the through hole 107 of the ceramic capacitor 101. Accordingly, the conductor forming portion 14 is disposed so as to be completely surrounded by the ceramic capacitor 101 in the through hole 107.

  The ceramic capacitor 101 of this embodiment is a so-called via array type ceramic capacitor. The ceramic sintered body 104 constituting the ceramic capacitor 101 includes one capacitor main surface 102 (upper surface in FIG. 1), one capacitor back surface 103 (lower surface in FIG. 1), and four capacitor side surfaces 106 (left surface in FIG. 1). , Right side).

  As shown in FIG. 5, the ceramic sintered body 104 has a structure in which power supply internal electrode layers 141 and ground internal electrode layers 142 are alternately stacked via a ceramic dielectric layer 105. The ceramic dielectric layer 105 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 power internal electrode layer 141 and the ground internal electrode layer 142. To do. Each of the power supply internal electrode layer 141 and the ground internal electrode layer 142 is a layer formed mainly of nickel, and is disposed in every other layer in the ceramic sintered body 104.

  As shown in FIGS. 5 to 8, a large number of via holes 130 are formed in the ceramic sintered body 104 of the ceramic capacitor 101. These via holes 130 penetrate the ceramic sintered body 104 in the thickness direction and are arranged in a lattice shape (array shape) over the entire surface. In each via hole 130, a plurality of in-capacitor via conductors 131 and 132 that communicate between the capacitor main surface 102 and the capacitor back surface 103 of the ceramic sintered body 104 are formed using nickel as a main material. That is, the current supply conductor 15 (see FIG. 1 and the like) is formed using a metal material (copper) having higher conductivity than the via conductors 131 and 132 in the capacitor. Each power supply capacitor internal via conductor 131 passes through each power supply internal electrode layer 141 and electrically connects them to each other. Each ground capacitor via conductor 132 passes through each ground internal electrode layer 142 and electrically connects them to each other. Each power source capacitor via conductor 131 and each ground capacitor inner via conductor 132 are arranged in an array as a whole. In the present embodiment, for convenience of explanation, the via conductors 131 and 132 in the capacitor are illustrated in 5 columns × 8 columns (or 6 columns), but there are actually more columns.

  As shown in FIGS. 5 and 6, a plurality of main surface side power supply electrodes 111 and a plurality of main surface side ground electrodes 112 are formed on the capacitor main surface 102 of the ceramic sintered body 104 in the ceramic capacitor 101. And project. Each main surface side ground electrode 112 is individually formed on the capacitor main surface 102, but may be formed integrally. The main surface side power supply electrode 111 is directly connected to the end surface of the plurality of power supply capacitor internal via conductors 131 on the capacitor main surface 102 side, and the main surface side ground electrode 112 is connected to the plurality of ground capacitor internal electrodes. The via conductor 132 is directly connected to the end surface on the capacitor main surface 102 side.

  Further, on the capacitor back surface 103 of the ceramic sintered body 104 in the ceramic capacitor 101, a plurality of back surface side power supply electrodes 121 and a plurality of back surface side ground electrodes 122 project. Each back surface side ground electrode 122 is individually formed on the capacitor back surface 103, but may be formed integrally. The back surface side power supply electrode 121 is directly connected to the end surface of the plurality of power supply capacitor internal via conductors 131 on the capacitor back surface 103 side, and the back surface side ground electrode 122 is connected to the plurality of ground internal capacitor capacitor via conductors 132. Is directly connected to the end surface on the capacitor back surface 103 side. Therefore, the power supply electrodes 111 and 121 are electrically connected to the power supply capacitor internal via conductor 131 and the power supply internal electrode layer 141, and the ground electrodes 112 and 122 are connected to the ground capacitor internal via conductor 132 and the ground internal electrode layer 142. Is conducting.

  As shown in FIGS. 4 to 6 and the like, the electrodes 111, 112, 121, and 122 are made of nickel as a main material, and the surface is entirely covered with a copper plating layer (not shown). In this embodiment, the electrodes 111, 112, 121, and 122 have a circular shape in a plan view with a diameter of about 500 μm, and the minimum pitch length is set to about 580 μm.

  As shown in FIG. 1, the electrodes 111 and 112 on the capacitor main surface 102 side are connected via the via conductor 47, the conductor layer 42, the via conductor 43, the terminal pad 44, the solder bump 45, and the surface connection terminal 22 of the MCM 21. And is electrically connected to the MCM 21. On the other hand, the electrodes 121 and 122 on the capacitor back surface 103 side are connected to electrodes (contactors) of a mother board (not shown) via via conductors 47, conductor layers 42, via conductors 43, PGA pads 48 and pins 49. Electrically connected.

  For example, when energization is performed from the motherboard side via the electrodes 121 and 122 and a voltage is applied between the power supply internal electrode layer 141 and the ground internal electrode layer 142, for example, positive charges are accumulated in the power supply internal electrode layer 141. For example, negative charges accumulate in the ground internal electrode layer 142. As a result, the ceramic capacitor 101 functions as a capacitor. In the ceramic capacitor 101, the via-conductor 131 for power supply capacitor and the via-conductor 132 for ground capacitor are alternately arranged adjacent to each other, and the via-conductor 131 for power-supply capacitor and the via-conductor 132 for ground capacitor are connected to each other. The directions of the flowing currents are set to be opposite to each other. Thereby, the inductance component is reduced.

  As shown in FIG. 1, each current supply conductor 15 formed in the conductor forming portion 14 is disposed in the component mounting region 23 of the current supply connection pad 19 and the first buildup layer 31. The first connection terminal 151 and the surface connection terminal 22 of the MCM 21 are electrically connected to the memory chip 26 of the MCM 21. Each of the current supply conductors 15 and the first connection terminal portion 151 constitutes a wiring for supplying a current to the memory chip 26 instead of a signal wiring for sending a signal. The first connection terminal portion 151 includes a via conductor 47, a conductor layer 42, a via conductor 43, a terminal pad 44 and a solder bump 45.

  In addition, a part of each power-source capacitor via conductor 131 and a part of each ground-capacitor via conductor 132 are connected to the main-surface-side power supply electrode 111 (or main-surface-side ground electrode 112) and the first. It is electrically connected to the microprocessor chip 24 included in the MCM 21 via the second connection terminal portion 152 included in the buildup layer 31 and the surface connection terminal 22. The second connection terminal portion 152 constitutes a wiring for electrically connecting the ceramic capacitor 101 and the microprocessor chip 24, and includes a via conductor 47, a conductor layer 42, a via conductor 43, a terminal pad 44 and a solder bump 45. It has become.

  Further, a part of each power-capacitor via conductor 131 and a part of each ground-capacitor via conductor 132 are connected to the main-surface-side power supply electrode 111 (or main-surface-side ground electrode 112) and the first. The buildup layer 31 is electrically connected to the microprocessor chip 25 included in the MCM 21 via the second connection terminal portion 153 included in the buildup layer 31 and the surface connection terminal 22. The second connection terminal portion 153 constitutes a wiring that electrically connects the ceramic capacitor 101 and the microprocessor chip 25, and includes a via conductor 47, a conductor layer 42, a via conductor 43, a terminal pad 44, and a solder bump 45. It has become. The second connection terminal portion 153 is electrically independent from the second connection terminal portion 152, and the second connection terminal portions 152 and 153 are arranged with the first connection terminal portion 151 interposed therebetween.

  Next, a method for manufacturing the wiring board 10 of this embodiment will be described.

  In the core substrate preparation step, an intermediate product of the core substrate 11 is prepared by a conventionally known technique and prepared in advance.

  The intermediate product of the core substrate 11 is manufactured as follows. First, a copper clad laminate (see FIG. 9) in which a copper foil 162 is bonded to both surfaces of a base material 161 having a length of 400 mm, a width of 400 mm, and a thickness of 0.6 mm is prepared. Next, the copper foil 162 on both sides of the copper-clad laminate is etched to pattern the conductor layer 163 by, for example, a subtractive method (see FIG. 10). 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 162 are removed by etching. Thereafter, the dry film is peeled off. Next, after roughening the upper and lower surfaces of the base material 161 and the conductor layer 163, an epoxy resin film (thickness of 80 μm) to which an inorganic filler has been added is attached to the upper and lower surfaces of the base material 161 by thermocompression bonding. Then, the sub-base material 164 is formed (see FIG. 11).

  Next, the conductor layer 41 is patterned on the upper surface of the upper sub-base material 164 and the lower surface of the lower sub-base material 164, respectively. Specifically, after performing electroless copper plating on the upper surface of the upper sub-base material 164 and the lower surface of the lower sub-base material 164, an etching resist is formed, and then electrolytic copper plating is performed. Further, the etching resist is removed and soft etching is performed. Next, the laminated body composed of the base material 161 and the sub base material 164 is drilled using a router to form a through hole serving as the accommodation hole 90 at a predetermined position (see FIG. 12).

  Further, drilling is performed using a YAG laser or a carbon dioxide gas laser, and through holes that penetrate the core substrate 11 are formed in advance at a plurality of locations. And after performing electroless copper plating with respect to the inner surface of each through-hole, an etching resist is formed and then electrolytic copper plating is performed. Further, the etching resist is removed and soft etching is performed. Thereby, the through-hole conductor 16 is formed in each through-hole. Then, the closing body 17 is filled in the through-hole conductor 16 to obtain an intermediate product of the core substrate 11 (see FIG. 13). The intermediate product of the core substrate 11 is a multi-piece core substrate having a structure in which a plurality of regions to be the core substrate 11 are arranged vertically and horizontally along the plane direction.

  In the conductor forming portion preparation step, an intermediate product of the conductor forming portion 14 is prepared by a method similar to the method for manufacturing the core substrate 11 and prepared in advance. First, the 1st base material 165 which consists of the same material as said base material 161 is prepared. Next, after the upper surface and the lower surface of the first base material 165 are roughened, the second base material 166 made of the same material as the sub-base material 164 is formed on the upper surface and the lower surface of the first base material 165.

  Next, the current supply connection pads 19 are pattern-formed on the upper surface of the upper second base material 166 and the lower surface of the lower second base material 166, respectively. Specifically, after performing electroless copper plating on the upper surface of the upper second base material 166 and the lower surface of the lower second base material 166, an etching resist is formed, and then electrolytic copper plating is performed. Then, the etching resist is removed and soft etching is performed.

  Further, drilling is performed using a YAG laser or a carbon dioxide laser, and through holes penetrating the conductor forming portion 14 are formed in advance at a plurality of locations. And after performing electroless copper plating with respect to the inner surface of each through-hole, an etching resist is formed and then electrolytic copper plating is performed. Further, the etching resist is removed and soft etching is performed. Thereby, the current supply conductor 15 is formed in each through hole. Then, the closing member 18 is filled in the current supply conductor 15 to obtain an intermediate product of the conductor forming portion 14. The intermediate product of the conductor forming portion 14 is a multi-cavity conductor forming portion having a structure in which a plurality of regions (conductor forming portion regions) to be the conductor forming portion 14 are arranged vertically and horizontally along the plane direction.

  Further, the multi-cavity conductor forming portion is divided. At this time, the conductor forming portion 14 is cut into a circular shape in each conductor forming portion region. As a result, a large number of conductor forming portions 14 which are individual products can be obtained simultaneously.

  In the capacitor preparation step, the ceramic capacitor 101 having the through hole 107 is prepared by a conventionally known technique and prepared in advance.

  The ceramic capacitor 101 is manufactured as follows. That is, a ceramic green sheet is formed, and nickel paste for internal electrode layers is screen printed on the green sheet and dried. As a result, a power internal electrode portion that will later become the power internal electrode layer 141 and a ground internal electrode portion that will be the ground internal electrode layer 142 are formed. Next, the green sheets with the power supply internal electrode portions and the green sheets with the ground internal electrode portions are alternately stacked, and each green sheet is integrated by applying a pressing force in the sheet stacking direction. To form a green sheet laminate.

  Further, a number of via holes 130 are formed through the green sheet laminate using a laser processing machine, and a via conductor nickel paste is filled into each via hole 130 using a paste press-fitting and filling device (not shown). Next, a paste is printed on the upper surface of the green sheet laminate, and the main surface side power supply electrode 111 and the main surface side ground electrode 112 so as to cover the upper end surface of each conductor portion on the upper surface side of the green sheet laminate. Form. Further, a paste is printed on the lower surface of the green sheet laminate, and the back-side power supply electrode 121 and the back-side ground electrode 122 are formed so as to cover the lower end surface of each conductor portion on the lower surface side of the green sheet laminate. .

  Thereafter, the green sheet laminate is dried to solidify the electrodes 111, 112, 121, and 122 to some extent. Next, the green sheet laminate is degreased and 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 104.

  Next, electroless copper plating (thickness of about 10 μm) is performed on each electrode 111, 112, 121, 122 included in the obtained ceramic sintered body 104. As a result, a copper plating layer is formed on each of the electrodes 111, 112, 121, 122, and the ceramic capacitor 101 is completed.

  In the subsequent housing step, the ceramic capacitor 101 is housed in the housing hole 90 using a mounting device (manufactured by Yamaha Motor Co., Ltd.) with the core main surface 12 and the capacitor main surface 102 facing the same side ( (See FIG. 14). The opening on the core back surface 13 side of the accommodation hole 90 is sealed with a peelable adhesive tape 171. The adhesive tape 171 is supported by a support base (not shown). The ceramic capacitor 101 is affixed and temporarily fixed to the adhesive surface of the adhesive tape 171 (see FIG. 15).

  Further, in the housing process, using the mounting device (manufactured by Yamaha Motor Co., Ltd.), with the core main surface 12 (and the capacitor main surface 102) and the main surface 167 facing the same side, the through hole of the ceramic capacitor 101 The conductor formation part 14 is accommodated in 107 (refer FIG. 15). As a result, the conductor forming portion 14 is disposed so as to be surrounded by the ceramic capacitor 101 in the through hole 107, and is affixed and temporarily fixed to the adhesive surface of the adhesive tape 171.

  Thereafter, a buildup layer forming step is performed. In the buildup layer forming step, the first buildup layer 31 is formed on the core main surface 12 and the second buildup layer 32 is formed on the core back surface 13 based on a conventionally known technique. More specifically, the lowermost resin insulation layer 33 is formed by depositing a photosensitive epoxy resin on the core main surface 12 and the capacitor main surface 102 and performing exposure and development. In place of depositing the photosensitive epoxy resin, an insulating resin or a liquid crystal polymer (LCP) may be deposited. In addition, the gap between the inner surface of the accommodation hole 90 and the capacitor side surface 106 is filled with the filler 33 a which is a part of the resin insulating layer 33. Thereafter, when heat treatment is performed, the resin insulating layer 33 (filler 33a) is cured, the ceramic capacitor 101 and the conductor forming portion 14 are fixed to the core substrate 11, and an intermediate product of the wiring substrate 10 is obtained. At this point, the adhesive tape 171 is peeled off.

  Next, a photosensitive epoxy resin is applied to the core back surface 13 and the capacitor back surface 103, and the resin insulating layer 34 is formed by performing exposure and development. Instead of depositing the photosensitive epoxy resin, an insulating resin or a liquid crystal polymer may be deposited. Further, laser drilling is performed using a YAG laser or a carbon dioxide laser to form via holes (not shown) at positions where via conductors 47 are to be formed. Specifically, a via hole penetrating the resin insulating layer 33 is formed to expose the main surface side power supply electrode 111 and the main surface side ground electrode 112. Further, a via hole penetrating the resin insulating layer 34 is formed to expose the back side power supply electrode 121 and the back side ground electrode 122. Next, electrolytic copper plating is performed according to a conventionally known method (for example, a semi-additive method) to form a via conductor 47 in the via hole, and a conductor layer 42 is formed on the first resin insulating layers 33 and 34. Form.

  Next, a photosensitive epoxy resin is deposited on the resin insulation layers 33 and 34, and exposure and development are performed to form resin insulation layers 35 and 36 having via holes at positions where the via conductors 43 are to be formed. To do. Instead of depositing the photosensitive epoxy resin, an insulating resin or a liquid crystal polymer may be deposited. In this case, a via hole is formed at a position where the via conductor 43 is to be formed by a laser processing machine or the like. Next, electrolytic copper plating is performed according to a conventionally known method to form a via conductor 43 in the via hole, a terminal pad 44 on the resin insulating layer 35, and a PGA pad on the resin insulating layer 36. 48 is formed.

  Next, solder resists 37 and 38 are formed by applying and curing a photosensitive epoxy resin on the resin insulating layers 35 and 36. Next, exposure and development are performed with a predetermined mask placed, and the openings 40 and 46 are patterned in the solder resists 37 and 38. Further, solder bumps 45 are formed on the terminal pads 44 and pins 49 are formed on the PGA pads 48. It can be understood that the product in this state is a multi-cavity wiring board in which a plurality of product regions to be the wiring board 10 are arranged vertically and horizontally along the plane direction. Furthermore, when the multi-cavity wiring board is divided, a large number of wiring boards 10 which are individual products can be obtained simultaneously.

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

  (1) According to the wiring substrate 10 of the present embodiment, since the through hole 107 exists in the ceramic capacitor 101, the conductor forming portion 14 is formed in the through hole 107 without dividing or reducing the ceramic capacitor 101. Can be placed without difficulty. Therefore, a large current is applied to the MCM 21 mounted in the component mounting region 23 where the first connection terminal portion 151 is disposed via the current supply conductor 15 formed in the conductor formation portion 14 and the first connection terminal portion 151. Can be supplied. In addition, regardless of the presence of the conductor forming portion 14, the ceramic capacitor 101 having a large area of the capacitor main surface 102 can be formed, so that the capacity of the ceramic capacitor 101 is increased and the ceramic capacitor 101 is mounted in the component mounting region 23. The MCM 21 is securely supported by the ceramic capacitor 101. Therefore, since the first buildup layer 31 is not easily deformed in the component mounting region 23, the mechanical stress applied to the MCM 21 can be reduced, and the reliability of the wiring board 10 can be improved.

  (2) In the present embodiment, the through hole 107 of the ceramic capacitor 101 has a circular cross section, and the through hole 107 has no corners. Therefore, stress concentration on a part (corner portion) of the through hole 107 due to a temperature change can be alleviated, so that generation of cracks in the through hole 107 can be prevented. In addition, since the opening area of the through hole 107 is easily reduced, the area of the capacitor main surface 102 is easily increased. As a result, the area of the internal electrode layers 141 and 142 of each layer can be increased, so that the capacitance of the ceramic capacitor 101 can be increased. Furthermore, the ceramic capacitor 101 of the present embodiment has a hollow structure provided with a through hole 107 opened at the capacitor main surface 102 and the capacitor back surface 103. Therefore, the mechanical strength of the ceramic capacitor 101 is increased and the warpage is less likely to occur compared to a structure having a through hole that opens at a part of the capacitor side surface 106 in addition to the capacitor main surface 102 and the capacitor back surface 103.

  (3) In the present embodiment, the current supply conductor 15 is electrically connected to the memory chip 26 and the ceramic capacitor 101 is electrically connected to the microprocessor chips 24 and 25. As a result, even if the memory chip 26 needs to supply a larger current than the microprocessor chips 24 and 25, the power supply system of the memory chip 26 and the microprocessor chips 24 and 25 cannot be shared. The memory chip 26 and the microprocessor chips 24 and 25 can be sufficiently operated. Therefore, when the structure in which the MCM 21 is mounted on the wiring board 10 as in the present embodiment is adopted, the merit can be maximized.

  (4) In the present embodiment, since the ceramic capacitor 101 is disposed immediately below the microprocessor chips 24 and 25, the wiring connecting the ceramic capacitor 101 and the microprocessor chips 24 and 25 is shortened, and the inductance component of the wiring is increased. Is prevented. Therefore, the switching noise of the microprocessor chips 24 and 25 due to the ceramic capacitor 101 can be reliably reduced, and the power supply voltage can be reliably stabilized. In addition, since noise entering between the MCM 21 and the ceramic capacitor 101 can be suppressed to a very low level, high reliability can be obtained without causing malfunction such as malfunction.

  (5) In the present embodiment, the filler that fills the gap between the inner surface of the accommodation hole 90 and the capacitor side surface 106 is the filler 33a that forms a part of the resin insulating layer 33. It is not necessary to prepare a material different from that for the layer 33. Therefore, since the material necessary for manufacturing the wiring board 10 is reduced, the cost of the wiring board 10 can be reduced.

  In addition, you may change this embodiment as follows.

  In the wiring substrate 10 of the above embodiment, the ceramic capacitor 101 having the through-hole 107 having a circular cross section, that is, a curved shape in plan view, is used. However, as shown in FIG. 16, a ceramic capacitor 182 having a linearly shaped through hole 181 may be used. It should be noted that the straight shape is easier to process the through hole than the curved shape, and the processing cost of the through hole can be reduced. The circular through hole 107 is preferable.

  -Although the conductor formation part 14 of the said embodiment was comprised separately from the core board | substrate 11, the conductor formation part 14 is a part of core substrate 11, and a part of base material 161 and sub A part of the base material 164 may be included. In this case, the conductor forming portion 14 is connected to the core substrate 11 via a connecting portion 169 including a part of the base material 161 and a part of the sub base material 164 (see FIG. 16). In addition, the conductor formation part 14 may be connected to the core board | substrate 11 only through the sub base material 164, for example.

  With the above configuration, at the time of manufacturing the wiring substrate 10, the center of the core substrate 11 is formed at the time when the through hole that becomes the accommodation hole 90 is formed in the laminated body including the base material 161 and the sub base material 164. The conductor formation part 14 is formed in the part. Therefore, in the housing step, it is only necessary to house only the ceramic capacitor 101 instead of housing both the ceramic capacitor 101 and the conductor forming portion 14 in the housing hole 90 (see FIGS. 17 and 18).

  In the above embodiment, the four current supply conductors 15 are formed in the conductor forming portion 14. However, the number of current supply conductors 15 may be five or more, or may be three or less. When the number of current supply conductors 15 is three or less, the diameter of the current supply conductor is preferably larger than the diameter of the current supply conductor 15 of the above embodiment.

  -In above-mentioned embodiment, although MCM21 was used as an electronic component, you may change into another electronic component. For example, a multi-core microprocessor in which a plurality of processor cores are integrated on one chip may be used as the electronic component. In this way, parallel processing of a plurality of threads (tasks) that could not be achieved by a single-core microprocessor having only one processor core per chip is possible, and the processing capacity of the entire system is improved. . In addition, fault tolerance is improved as compared to a single-core microprocessor.

  Further, as shown in FIG. 19, the relay substrate 27 of the above embodiment may be omitted, and the microprocessor chips 24 and 25 and the memory chip 26 may be used as electronic components, respectively. That is, the surface connection terminals 22 may be provided on the lower surfaces of the microprocessor chips 24 and 25 and the memory chip 26, respectively, and the microprocessor chips 24 and 25 and the memory chip 26 may be directly mounted on the component mounting area 23.

  In the above embodiment, the filler 33a that is a part of the resin insulating layer 33 is used to form a gap between the inner surface of the accommodation hole 90 and the capacitor side surface 106, and the inner wall surface of the through hole 107 of the ceramic capacitor 101 and conductor formation. The gap with the side surface of the portion 14 was filled. However, the gap may be filled using a filler different from the filler 33a. In this way, the function of the filler 33a can be specialized to the function of fixing the ceramic capacitor 101 and the conductor forming portion 14, and thus the reliability of the wiring board 10 can be improved.

  Next, in addition to the technical ideas described in the claims, the technical ideas grasped by the embodiment described above are listed below.

  (1) A core substrate having a core main surface and a core back surface and having an accommodation hole opened at least on the core main surface side; a capacitor main surface and a capacitor back surface; and the capacitor main surface and the capacitor back surface A capacitor having a through hole penetrating through the capacitor, and the core main surface and the capacitor main surface facing the same side, the capacitor housed in the housing hole, the core back surface side and the core main surface A conductor for current supply that conducts the side is formed, and a conductor forming portion disposed so as to be surrounded by the capacitor in the through hole of the capacitor, an interlayer insulating layer and a conductor layer are laminated on the core main surface A component mounting area on which an electronic component can be mounted is set on the surface, and a first connection terminal portion electrically connected to the current supply conductor is disposed in the component mounting area; A wiring laminated portion in which a plurality of second connection terminal portions are disposed across the first connection terminal portion, and the through hole and the conductor forming portion are disposed in a central portion of the core substrate, A wiring board with a built-in capacitor, characterized by having a shape with no corners.

  (2) A core substrate having a core main surface and a core back surface and having an accommodation hole opened at least on the core main surface side; a capacitor main surface and a capacitor back surface; and the capacitor main surface and the capacitor back surface A capacitor having a through hole penetrating through the capacitor, and the core main surface and the capacitor main surface facing the same side, the capacitor housed in the housing hole, the core back surface side and the core main surface A conductor for current supply that conducts the side is formed, and a conductor forming portion disposed so as to be surrounded by the capacitor in the through hole of the capacitor, an interlayer insulating layer and a conductor layer are laminated on the core main surface A component mounting area on which an electronic component can be mounted is set on the surface, and a first connection terminal portion electrically connected to the current supply conductor is disposed in the component mounting area; First connection across the terminal portions and a plurality of second connection terminal portions arranged wiring laminated portion, the capacitor built-in wiring board, characterized in that the conductor containing portion is not present the signal wiring.

  (3) A core substrate having a core main surface and a core back surface and having an accommodation hole opened at least on the core main surface side; a capacitor main surface and a capacitor back surface; and the capacitor main surface and the capacitor back surface A capacitor having a through hole penetrating through the capacitor, and the core main surface and the capacitor main surface facing the same side, the capacitor housed in the housing hole, the core back surface side and the core main surface A conductor for current supply that conducts the side is formed, and a conductor forming portion disposed so as to be surrounded by the capacitor in the through hole of the capacitor, an interlayer insulating layer and a conductor layer are laminated on the core main surface A component mounting area on which an electronic component can be mounted is set on the surface, and a first connection terminal portion electrically connected to the current supply conductor is disposed in the component mounting area; And a wiring laminated portion in which a plurality of second connecting terminal portions are arranged with the first connecting terminal portion interposed therebetween, and the capacitor has a structure in which a plurality of internal electrode layers are laminated and disposed via a dielectric layer. A plurality of in-capacitor via conductors connected to the plurality of internal electrode layers, and a plurality of surface layer electrodes connected to at least the capacitor main surface side end of the plurality of in-capacitor via conductors, A wiring board with a built-in capacitor, which is a via array type capacitor in which a plurality of via conductors in a capacitor are arranged in an array as a whole.

1 is a schematic cross-sectional view showing a wiring board according to an embodiment of the present invention. The schematic side view of MCM. The schematic plan view of MCM. Explanatory drawing which shows positional relationships, such as a core board | substrate, a conductor formation part, a ceramic capacitor, and MCM. The schematic sectional drawing which shows a ceramic capacitor. The schematic plan view which shows the capacitor | condenser main surface side of a ceramic capacitor. 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. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing of the manufacturing method of a wiring board. Explanatory drawing which shows the positional relationship of the core board | substrate, conductor formation part, ceramic capacitor, MCM, etc. in other embodiment. Similarly, explanatory drawing of the manufacturing method of a wiring board. Similarly, explanatory drawing of the manufacturing method of a wiring board. The schematic sectional drawing which shows the wiring board in other embodiment. The schematic sectional drawing which shows the wiring board in a prior art. Similarly, the explanatory view showing the positional relationship of the core substrate, ceramic capacitor, MCM and the like.

Explanation of symbols

10 ... Wiring board with built-in capacitor (wiring board)
DESCRIPTION OF SYMBOLS 11 ... Core board | substrate 12 ... Core main surface 13 ... Core back surface 14 ... Conductor formation part 15 ... Current supply conductor 19 ... Current supply connection pad 21 ... Multi-chip module (MCM) as an electronic component
23... Component mounting areas 24 and 25... Microprocessor chip 26 as an arithmetic processing circuit unit... Memory chip 31 as a shared circuit unit... First buildup layers 33 and 35 as wiring layered units. Layer 39 ... Surface 42 of wiring laminated portion ... Conductor layer 90 ... Housing holes 101 and 182 ... Ceramic capacitor 102 as capacitor ... Capacitor main surface 103 ... Capacitor back face 107 and 181 ... Through hole 131 ... For power supply as via conductor in capacitor Capacitor via conductor 132... Ground capacitor inner via conductor 151 as a capacitor via conductor 151... First connection terminal portions 152, 153.

Claims (5)

A core substrate having a core main surface and a core back surface, in which an accommodation hole opened at least on the core main surface side;
The housing has a capacitor main surface and a capacitor back surface, and has a deformed plate shape having a through-hole penetrating the capacitor main surface and the capacitor back surface, with the core main surface and the capacitor main surface facing the same side. A capacitor housed in the hole;
A conductor forming portion that is formed so as to be electrically connected to the core back surface side and the core main surface side, and is disposed so as to be surrounded by the capacitor in the through hole of the capacitor; and
An interlayer insulating layer and a conductor layer are laminated on the core main surface, and a component mounting area on which electronic components can be mounted is set on the surface, and the current supply conductor is electrically connected to the component mounting area. The connected first connection terminal portion is disposed, and a wiring laminated portion in which a plurality of second connection terminal portions are disposed across the first connection terminal portion , and
The capacitor is a via array type ceramic capacitor having a substantially rectangular shape in plan view and having a plurality of via conductors in the capacitor,
The conductor forming portion is configured separately from the core substrate,
The wiring board with a built-in capacitor, wherein the through hole and the conductor forming portion have a shape with no corners in plan view .   The plurality of second connection terminal portions are electrically connected to a plurality of arithmetic processing circuit portions included in the electronic component, respectively, and the first connection terminal portions are used jointly by the plurality of arithmetic processing circuit portions. The wiring board with a built-in capacitor according to claim 1, wherein the wiring board is electrically connected to a shared circuit unit that requires a larger current than the plurality of arithmetic processing circuit units. 3. The capacitor built-in wiring board according to claim 1, wherein the current supply conductor is formed using a metal material having higher conductivity than the plurality of capacitor via conductors. The end of the current supply conductors, the capacitor according to any one of claims 1 to 3, characterized in that the current supply current supplying connection pad also has larger diameter than the conductor is provided Built-in wiring board. The through hole, the capacitor built-in wiring board according to any one of claims 1 to 4, characterized in that a circular cross-section.

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