JP2007005041A - Sheet material with high dielectric constant, manufacturing method of the same, and wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet material with a high dielectric constant easily made to have large capacity. <P>SOLUTION: The sheet material with high dielectric constant 20 has a dielectric layer 21, and the dielectric layer has a plurality of dielectric particles 22. The plurality of dielectric particles 22 are arranged in a two-dimensional monolayer along a planar direction of the dielectric layer 21. The dielectric particles 22 are stuck to each other by a material 23. By the above, the dielectric particle 22 having a relatively high dielectric constant and the material 23 having a relatively low dielectric constant are prevented from being arrayed in series in a thickness direction of the dielectric layer 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a high dielectric constant material sheet including a dielectric layer, a method for manufacturing the same, and a wiring board in which the high dielectric constant material sheet is embedded.

  In recent years, there has been a high demand for high performance and miniaturization of electronic devices, and the demand for higher density and higher functionality of electronic components has been steadily increasing as such demands have increased. Therefore, in order to increase the mounting efficiency of the electronic components on the wiring board, for example, various electronic parts (capacitors, etc.) for embedding the wiring board have been proposed.

  Incidentally, a capacitor for embedding a wiring board generally has a structure in which a high dielectric constant sheet made of a ceramic sintered body is sandwiched between electrodes (see, for example, Patent Document 1). The high dielectric constant sheet is manufactured by firing a green sheet containing an unsintered dielectric ceramic. In this way, the dielectric constant of the high dielectric constant material sheet can be relatively easily increased, and a high-capacitance capacitor can be easily manufactured. However, in the above wiring board, after the green sheet is fired together with the electrode forming metal at a high temperature for a predetermined time to produce a high dielectric constant material sheet, the high dielectric constant material sheet on which the electrode is formed is placed in the insulating layer of the wiring board. It is manufactured by embedding. However, since the ratio of firing shrinkage and the coefficient of thermal expansion differ between metal and ceramic, warping or peeling is likely to occur during production. Therefore, a highly reliable wiring board with a built-in capacitor cannot be manufactured.

As a capacitor (capacitor layer) manufactured without firing at a high temperature, for example, a capacitor (capacitor layer) in which high dielectric particles are dispersed in an organic resin material has been conventionally proposed (for example, Patent Document 2). 3). For example, as shown in FIG. 31, the capacitor 121 includes a dielectric layer 122 and electrodes 123 formed on the upper and lower surfaces of the dielectric layer 122. The dielectric layer 122 is formed by mixing dielectric particles 124 made of barium titanate and an interlayer insulating material 125 made of an organic material. Note that the capacitor 121 is required to have as high a capacitance as possible. For this purpose, for example, it is considered preferable to use a dielectric particle 124 having a high relative dielectric constant.
Japanese Patent Publication No. 6-14580 JP 2003-292733 A Japanese Unexamined Patent Publication No. 2004-292848 (FIG. 3 etc.)

  However, in the conventional capacitor 121, not only the dielectric particles 124 having a high dielectric constant are interposed between both electrodes 123, but also the interlayer insulating material 125 having a dielectric constant relatively lower than that of the dielectric particles 124. Intervene. As a result, a portion having a low dielectric constant exists between both electrodes 123, so that even if dielectric particles 124 having a high dielectric constant are used, the dielectric constant of the entire capacitor 121 can be increased as expected. Can not. Therefore, it is difficult to increase the capacity of the entire capacitor 121.

  The present invention has been made in view of the above problems, and a first object of the present invention is to provide a high dielectric constant material sheet that can be easily increased in capacity. The second object is to provide a method for producing a high dielectric constant material sheet capable of easily and reliably obtaining the above excellent high dielectric constant material sheet. A third object is to provide a wiring board in which the above-described excellent high dielectric constant material sheet is embedded.

  A means (means 1) for solving the above-mentioned problem is a high dielectric constant material sheet including a dielectric layer having a first main surface and a second main surface, wherein the dielectric layer is the dielectric layer. A high dielectric constant material sheet comprising: a plurality of dielectric grains arranged two-dimensionally and in a single layer along a plane direction of the body layer; and a material for fixing the plurality of dielectric grains to each other There is.

  Therefore, according to the high dielectric constant material sheet of the above means 1, since the dielectric particles are arranged in a single layer along the plane direction of the dielectric layer, in the portion where the dielectric particles exist in the dielectric layer, Only the dielectric grains can be arranged along the thickness direction of the dielectric layer. For this reason, it becomes easy to raise the dielectric constant of the whole high dielectric constant material sheet, and it becomes easy to increase the capacity of the high dielectric constant material sheet.

  The dielectric particles according to the means 1 mean a granular material whose main component is an inorganic material (for example, ceramic) having a higher dielectric constant than a material for fixing a plurality of dielectric particles. Examples of the ceramic include zirconia, alumina, silicon nitride, boron nitride, silicon carbide, aluminum nitride, barium titanate, and strontium titanate. In particular, a high dielectric constant ceramic is preferable. Here, the high dielectric constant ceramic means a ceramic having a relative dielectric constant of 10 or more, and it is particularly preferable that the relative dielectric constant is 100 or more. In this way, since the dielectric constant of the entire high dielectric constant material sheet is further increased, it is easier to increase the capacity of the high dielectric constant material sheet. Examples of the high dielectric constant ceramic include barium titanate, strontium titanate, and perovskite oxide having a perovskite crystal structure. Specific examples of the perovskite oxide include compounds composed of one or more selected from barium titanate, lead titanate, and strontium titanate.

  Further, the dielectric particles may be composed of a single particle or a plurality of particles. In the case of dielectric particles composed of a plurality of particles, the dielectric particles include those formed by sintering (chemically bonding) the plurality of particles in a pressed state. Further, the plurality of dielectric particles may be substantially spherical (for example, true spherical, elliptical spherical, etc.), or non-spherical such as substantially columnar (for example, substantially cylindrical, substantially quadrangular, substantially triangular, etc.). Although the shape may be sufficient, it is particularly preferable that the shape is substantially spherical. In this way, when the high dielectric constant material sheet is manufactured, it is not necessary to consider the direction of the dielectric particles when holding the plurality of dielectric particles on the plurality of positioning portions of the jig. Therefore, a high dielectric constant material sheet can be manufactured efficiently. The plurality of dielectric grains preferably have a high sphericity and preferably have a uniform grain size. In this way, it becomes easy to hold the dielectric particles with respect to the positioning portion, and it becomes easy to manufacture a high dielectric constant material sheet.

  Further, the particle diameter of the plurality of dielectric grains is preferably larger than the maximum thickness of the material for fixing the plurality of dielectric grains, and specifically, it is preferably 10 μm or more and 50 μm or less. If the particle size of the dielectric particles is less than 10 μm, it is difficult to hold the dielectric particles with respect to the positioning portion. On the other hand, when the particle size of the dielectric particles is larger than 50 μm, the entire high dielectric constant material sheet becomes thick. In particular, when the dielectric grains are not spherical but elliptical, the length of the dielectric layer in the thickness direction (thickness diameter) is the maximum of the material that fixes the plurality of dielectric grains together. It is preferable that the thickness is larger than the thickness.

  As a method of arranging a plurality of dielectric grains two-dimensionally and in a single layer along the plane direction of the dielectric layer, a plurality of dielectric grains are latticed along the plane direction of the dielectric layer. For example, it may be arranged in a zigzag pattern. When configured in this manner, the dielectric grains are uniformly arranged along the planar direction of the dielectric layer, so that the mechanical strength of the high dielectric constant material sheet can be increased uniformly. In addition, when manufacturing a so-called multi-piece high dielectric constant material sheet and dividing the multi-piece high dielectric constant material sheet to obtain a high dielectric constant material sheet, the volume of dielectric particles for each high dielectric constant material sheet The variation in the ratio is reduced. Therefore, it is possible to prevent variation in capacitance between the high dielectric constant material sheets.

  In addition, a part of the plurality of dielectric grains can be exposed on at least one of the first main surface and the second main surface. In this case, another layer (such as a metal layer serving as an electrode) can be bonded to the exposed portion of the dielectric grains. The term “exposed” refers to a state in which a part of the dielectric particles appears on at least one of the first main surface and the second main surface, and the exposed portion of the dielectric particles is the other layer. It may be covered with. In addition, it is preferable that a part of the plurality of dielectric grains is exposed on both the first main surface and the second main surface. If it does in this way, another layer can be joined to the exposed part of a dielectric grain also in the 1st principal surface and the 2nd principal surface.

  Furthermore, the plurality of dielectric grains protrude from the surface of the material that fixes the plurality of dielectric grains, thereby forming irregularities on at least one of the first main surface and the second main surface. It is preferable. In this way, the physical coupling force acting on the interface between the dielectric layer and the other layer is increased, and the adhesion of the other layer to the dielectric layer is improved. Therefore, it is possible to realize a high dielectric constant material sheet excellent in reliability. Specifically, in the first main surface and / or the second main surface on which the unevenness is formed, the height difference between the dielectric particles and the material that fixes the dielectric particles is 1 μm or more and 10 μm or less. It is preferable. The reason for this is that if the height difference between the dielectric particles and the material that fixes the dielectric particles becomes too large, the other layers will not enter the concave parts, so that sufficient physical adhesion cannot be obtained. is there. Further, since the thickness of the dielectric layer is substantially increased, for example, when a capacitor is formed of a high dielectric constant material sheet, the capacitance is reduced.

  In the high dielectric constant material sheet, the difference in height between the dielectric grains and the material fixing the dielectric grains on the first main surface and / or the second main surface on which the irregularities are formed is more than 1 μm. Set to be larger. The reason is that if the height difference between the dielectric particles and the material that fixes the dielectric particles is less than this value, the dielectric layer does not lead to improved adhesion, and sufficient physical adhesion can be obtained. Because there is no. Of course, the difference in height between the dielectric grains and the material that fixes the dielectric grains does not exceed the effective diameter of the dielectric grains.

  The thickness of the material for fixing the plurality of dielectric grains to each other is preferably set to 5 μm or more and 45 μm or less. By setting the thickness of the material to 5 μm or more, it is possible to ensure high mechanical strength of the high dielectric constant material sheet and increase the size of the high dielectric constant material sheet in the thickness direction (Z direction). Can be prevented. On the other hand, by setting the thickness of the material to 45 μm or less, a part of the dielectric particles can be easily exposed on at least one of the first main surface and the second main surface. In order to expose a part of the dielectric particles on both the first main surface and the second main surface, the thickness of the material for fixing the plurality of dielectric particles to each other is such that the plurality of dielectric particles It is preferable that it is smaller than the diameter.

  In addition, a material for fixing a plurality of dielectric particles can be appropriately selected in consideration of cost, bonding properties, insulating properties, mechanical strength, and the like. In addition, when dielectric particles are made of ceramic and a plating layer (metal layer) is directly formed on at least one of the first main surface and the second main surface, the plating adhesion strength is low on the dielectric particles. In this case, it is preferable to use an organic resin material having high plating adhesion strength as a material for fixing a plurality of dielectric particles. In addition, when manufacturing a high dielectric constant material sheet, an organic resin that is easy to grind is used in the case of performing a grain exposure process in which a material for fixing a plurality of dielectric grains is ground to expose a part of the dielectric grains. It is preferable to use a material. Note that the reason why the organic resin material has higher plating adhesion strength than the ceramic is considered to be the difference in the surface condition when roughened. When the ceramic is roughened, only a valley-shaped back portion is formed on the surface. However, when the organic resin material is roughened, an anchor portion having a shape entering the back is formed. As a result, since the plating enters the anchor portion of the organic resin material, a strong adhesion can be obtained. The organic resin material is preferably a material having a large force for fixing a plurality of dielectric particles, and suitable examples include an epoxy resin, a polyimide resin, a polyamideimide resin, and a 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.

  In addition, it is preferable that the relative dielectric constant of a material (low dielectric constant material) for fixing a plurality of dielectric grains is as high as possible. However, since the material is often an organic resin material in consideration of cost, the actual dielectric constant is considerably lower than the dielectric constant of the dielectric particles (high dielectric constant material) (for example, 5 or less). Therefore, it is preferable that the volume ratio of the high dielectric constant material in the dielectric layer be as large as possible than the volume ratio of the low dielectric constant material in the dielectric layer. For example, the volume ratio of the high dielectric constant material is preferably set to 60% or more, and the remaining portion is preferably made of the low dielectric constant material. In particular, the volume ratio of the high dielectric constant material is preferably set to 70% or more, and the remaining portion is preferably a low dielectric constant material. In this way, since the dielectric constant of the entire high dielectric constant material sheet is increased, it is easier to increase the capacity of the high dielectric constant material sheet.

  The high dielectric constant material sheet can be a material for forming a laminated electronic component formed by laminating a metal layer and a dielectric portion. Specific examples include capacitors. The total thickness of the high dielectric constant material sheet is not particularly limited, but may be, for example, 1 μm or more and 100 μm or less, and preferably 5 μm or more and 75 μm or less. If the overall thickness is too thin, it becomes difficult to handle as a single sheet. On the other hand, if the overall thickness is too thick, there is a risk of hindering the achievement of high density and miniaturization of the wiring board when the high dielectric constant material sheet is embedded in the wiring board. Moreover, since the level | step difference will arise easily if the whole thickness is too thick, there exists a possibility that it may become difficult to ensure the smoothness of the substrate surface. That is, the high dielectric constant material sheet may be a material for forming an electronic component for embedding a wiring board.

  Furthermore, it is preferable that the high dielectric constant material sheet further includes a carrier material that adheres to at least one of the first main surface and the second main surface to protect the dielectric layer. In this way, it is possible to prevent the dielectric layer from being damaged when the high dielectric constant material sheet is manufactured. Further, even if the dielectric layer is thin, the carrier layer becomes thick due to adhesion, so that the handleability of the dielectric layer is improved.

  The high dielectric constant material sheet may further include a metal layer formed directly on at least one of the first main surface and the second main surface. According to this configuration, the metal layer as the other layer can be a high dielectric constant material sheet in close contact with the dielectric layer without using other materials such as an adhesive. Therefore, since the dielectric grains and other materials do not exist in series along the thickness direction of the dielectric layer, it is easy to achieve a high dielectric constant.

  Such a metal layer may be directly formed on one surface (one of the first main surface and the second main surface) of the dielectric layer, or both surfaces (the first main surface and the second main surface). (Both) may be formed directly. When the metal layer directly formed on both the first main surface and the second main surface is provided, the high dielectric constant material sheet is, for example, a capacitor.

  When the high dielectric constant material sheet includes a metal layer, the metal layer is preferably formed using a material having excellent conductivity. Specifically, silver, gold, platinum, copper, titanium, aluminum, It may be formed using one or more alloys selected from palladium, nickel, tungsten and the like. In particular, it is preferable to use, for example, copper or silver as the material for forming the metal layer. This is because copper and silver have high conductivity and are suitable as electrode materials.

  The thickness of the metal layer is preferably, for example, from 0.1 μm to 50 μm. This is because if the metal layer is too thin, it may be difficult to ensure electrical reliability. On the other hand, if the metal layer becomes too thick, the thickness of the high dielectric constant material sheet may increase. In that respect, if the thickness is set within a range of 0.1 μm or more and 50 μm or less, it is possible to prevent an increase in the thickness of the entire high dielectric constant material sheet while ensuring electrical reliability.

  Examples of the metal layer include a plating layer, a metal paste layer, a metal foil sticking layer, a sputtering layer, a vapor deposition layer, and an ion plating layer. Among these, a plating layer is preferable. This is because the plating layer can be formed in a short time and is advantageous in reducing the cost of the high dielectric constant material sheet.

  The high dielectric constant material sheet may be a material for forming an active component such as a semiconductor integrated circuit chip, a transistor, or a diode, or may be an active component itself. The high dielectric constant material sheet may be a material for forming a passive component such as a resistor, a capacitor, an inductor, or a coil, or may be a passive component itself. Note that the high dielectric constant material sheet referred to here does not only refer to the finished product of the high dielectric constant material sheet, but only after a metal layer is formed later (for example, after being embedded in a wiring board). The completed high dielectric constant material sheet is also included.

  Further, as another means (means 2) for solving the above problem, there is a wiring board characterized in that the high dielectric constant material sheet of the means 1 is embedded.

  Therefore, according to the wiring board of the above means 2, since the high-permittivity material sheet having a high capacity is embedded, when the high-permittivity material sheet is a capacitor, noise can be removed efficiently and the IC chip. It is possible to stabilize the power to be supplied to the IC chip and to supply power to the IC chip and the like. Further, as a result of the high dielectric constant material sheet being embedded in the wiring board, the component mountable area on the surface of the wiring board is increased, so that other electronic components can be mounted there.

  In addition, since the dielectric grains are arranged in a single layer along the plane direction of the dielectric layer, the dielectric layer is formed along the thickness direction of the dielectric layer in the portion where the dielectric grains exist in the dielectric layer. Only grains can be placed. For this reason, it becomes easy to raise the dielectric constant of the whole high dielectric constant material sheet, and it becomes easy to increase the capacity of the high dielectric constant material sheet.

  The wiring substrate has a configuration in which, for example, an insulating layer and a conductor layer are formed on a core substrate. In this case, the high dielectric constant material sheet may be embedded in the core substrate, may be embedded between the core substrate and the insulating layer, or may be embedded in the insulating layer. In addition, other components such as resistance elements and inductors may be embedded in the wiring board.

  The material for forming the core substrate is not particularly limited, and can be appropriately selected in consideration of cost, workability, insulation, mechanical strength, and the like. Examples of the core substrate include a resin substrate, a ceramic substrate, and a metal substrate. Specific examples of the resin substrate include an EP resin (epoxy resin) substrate, a PI resin (polyimide resin) substrate, a BT resin (bismaleimide-triazine resin) substrate, and a PPE resin (polyphenylene ether resin) substrate. In addition, a substrate made of a composite material of these resins and organic fibers such as glass fibers (glass woven fabric or glass nonwoven fabric) or polyamide fibers may be used. Alternatively, a substrate made of a resin-resin composite material obtained by impregnating a thermosetting resin such as an epoxy resin with a three-dimensional network fluorine-based resin base material such as continuous porous PTFE may be used. Specific examples of the ceramic substrate include an alumina substrate, a beryllia substrate, a glass ceramic substrate, and a substrate made of a low-temperature fired material such as crystallized glass. Specific examples of the metal substrate include a copper substrate, a copper alloy substrate, a substrate made of a single metal other than copper, and a substrate made of an alloy of a metal other than copper.

  An example of a suitable insulating layer formed on the core substrate is a resin insulating layer. The reason is that the resin insulating layer is preferable as a support for the high dielectric constant material sheet, and therefore, for example, a structure in which the high dielectric constant material sheet is embedded can be easily realized. Therefore, the mass productivity and the ability to cope with costs are increased. Further, it is advantageous for increasing the size of the wiring board. The resin insulating layer is formed using, for example, a thermosetting resin such as an EP resin (epoxy resin), a PI resin (polyimide resin), a BT resin (bismaleidotriazine resin), a phenol resin, a xylene resin, or a polyester resin. The

  The conductor layer is patterned on the core substrate or the insulating layer by a known method such as a subtractive method, a semi-additive method, or a full additive method. Examples of the metal material used for forming the conductor layer include copper, a copper alloy, nickel, a nickel alloy, tin, and a tin alloy. A built-up layer in which conductor layers and insulating layers are alternately laminated may be formed on one or both surfaces of the core substrate.

  As a preferable method (means 3) for relatively easily and reliably manufacturing the high dielectric constant material sheet described in means 1, a structure in which a plurality of positioning portions are two-dimensionally arranged along the jig main surface And positioning the plurality of dielectric grains two-dimensionally and in a single layer along the jig main surface by holding the plurality of dielectric grains in the plurality of positioning portions. Preparing a carrier material having an adhesion layer and transferring the plurality of dielectric particles positioned on the jig onto the adhesion layer; and transferring the plurality of dielectric particles to each other There is a method of manufacturing a high dielectric constant material sheet, which includes a fixing step of fixing the substrate with an organic resin material to form a dielectric layer.

  Therefore, according to the means 3, since the plurality of dielectric particles are held by the plurality of positioning portions of the jig in the positioning step, the plurality of dielectric particles can be reliably arranged. When the transfer process is performed, the plurality of dielectric grains are temporarily fixed to the carrier material, so that the positional relationship between the plurality of dielectric grains can be maintained. Thereafter, if a fixing step is performed, a plurality of dielectric grains can be fixed to each other while maintaining the positional relationship, so that the high dielectric constant material sheet of the means 1 can be obtained relatively easily.

  In addition, since the dielectric grains are arranged in a single layer along the plane direction of the dielectric layer, the dielectric layer is formed along the thickness direction of the dielectric layer in the portion where the dielectric grains exist in the dielectric layer. Only grains can be placed. For this reason, it becomes easy to raise the dielectric constant of the whole high dielectric constant material sheet, and it becomes easy to increase the capacity of the high dielectric constant material sheet.

  Hereinafter, the manufacturing method of the high dielectric constant material sheet described in the means 3 will be described.

  First, a jig having a structure in which a plurality of positioning portions are two-dimensionally arranged along the jig main surface is prepared, and a positioning step is performed. As the jig used in the positioning step, a jig having a recess for supporting a plurality of dielectric grains, or a jig (mesh member) having a mesh smaller than the grain diameter of the plurality of dielectric grains. The mesh member is preferable. This is because the mesh member has a small mesh and can be used as a suitable positioning portion for holding the dielectric grains. Moreover, it is because the printing screen of a commercially available screen printing machine can also be used as a jig.

  The mesh member is more preferably made of metal. Since the mesh member made of metal has high strength, it is possible to prevent deformation of the mesh member even when evacuation is performed through the plurality of positioning portions when holding the plurality of dielectric grains in each positioning portion, for example. It is. In addition, since the metal mesh member is not easily affected by static electricity, movement of a plurality of dielectric particles due to static electricity can be prevented.

  In the positioning step, a plurality of dielectric grains are held in a plurality of positioning portions of the jig. As the dielectric grains, compounds composed of one or more selected from the above-mentioned barium titanate, lead titanate and strontium titanate are suitable.

  Next, a carrier material having an adhesion layer is prepared and a transfer process is performed. Here, the carrier material used in the transfer step is preferably a resin film having an adhesion layer. If it does in this way, a commercially available resin film can be used as a carrier material. The resin film is preferably transparent. If it does in this way, the fixed situation of a plurality of dielectric particles can be checked via a resin film. The adhesion layer may be an adhesive layer or an adhesive layer, but is preferably an adhesive layer. If it is an adhesive layer, it is easier to peel off the carrier material than if it is an adhesive layer. Also, the carrier material can be reused. The carrier material used in the transfer step may be a conductive metal foil that has an adhesive layer and should be used later as an electrode. In this way, it is not necessary to perform the metal layer forming step of directly forming the metal layer on the dielectric layer, so that a high dielectric constant material sheet can be manufactured efficiently. Examples of the conductive metal foil include copper foil, nickel foil, silver foil, and gold foil.

  In the transfer step, the adhesion layer side of the carrier material is disposed above the jig, and the adhesion layer is brought into contact with a plurality of dielectric grains held on the jig. In this state, a pressing force is applied in the vertical direction. As a result, the plurality of dielectric particles positioned on the jig are transferred onto the adhesion layer. In the transfer step, it is preferable that a part of the plurality of dielectric particles is embedded in the adhesion layer when the plurality of dielectric particles are transferred onto the adhesion layer. In this way, the contact area between the dielectric particles and the adhesion layer is increased, so that a plurality of dielectric particles can be reliably temporarily fixed at desired positions. In addition, when the carrier material is peeled off, part of the plurality of dielectric grains can be exposed from the organic resin material.

  Next, an adhering step of adhering the transferred plurality of dielectric particles with an organic resin material to form a dielectric layer is performed. More specifically, for example, a sheet-like organic resin material is disposed on an adhesion layer of a carrier material onto which a plurality of dielectric particles are transferred, and a pressing force is applied in the same direction as the vertical direction while heating in this state. As a result, a part of the organic resin material enters between the dielectric grains, and the plurality of dielectric grains are fixed to each other. In addition, you may make it adhere | attach several dielectric particle | grains by pouring between the dielectric particle | grains and cooling the organic resin material heat-dissolved.

  Note that, after the fixing step, a grain exposing step for exposing a part of the plurality of dielectric grains may be performed. The grain exposure process is preferably an unevenness forming process in which unevenness is formed on the surface of the dielectric layer by causing some of the plurality of dielectric grains to protrude from the organic resin material. As a technique for exposing or projecting a part of the dielectric grains, for example, by removing the surface layer of the organic resin material by surface grinding, a part of the plurality of dielectric grains is exposed or projected from the organic resin material. A physical method is used. Further, as another method of exposing or projecting a part of the dielectric grains, for example, by removing the surface layer of the organic resin material by plasma ashing or etching process, a part of the plurality of dielectric grains is A chemical method that exposes or protrudes from the organic resin material is used. According to the plasma ashing or the etching process, when the surface layer of the organic resin material is removed, no physical stress is applied to the dielectric particles, so that a suitable shape of the dielectric particles can be maintained even after the removal. This is considered preferable for improving the adhesion.

  In the grain exposure step (the concavo-convex forming step), it is preferable that a part of the plurality of dielectric grains protrude from the organic resin material by peeling off the carrier material. In this way, a part of the plurality of dielectric particles can be easily exposed (protruded) from the organic resin material, so that a high dielectric constant material sheet can be produced efficiently.

  In addition, after the fixing step, the grain exposing step, and the unevenness forming step, a metal layer forming step of directly forming a metal layer on the dielectric layer may be performed. Examples of the method for directly forming the metal layer include plating, printing and baking of metal paste, sticking of metal foil, sputtering, vapor deposition, ion plating, and the like. When it is desired to form a very thin metal layer of 0.1 μm or more and 10 μm or less, it is particularly preferable to select a method such as plating, sputtering, CVD, PVD, or ion plating. In particular, the plating method enables a large amount of processing, which is advantageous for reducing the cost of the high dielectric constant material sheet.

[First Embodiment]

  Hereinafter, a ceramic capacitor built-in wiring board and a manufacturing method thereof according to a first embodiment embodying the present invention will be described with reference to FIGS.

  As shown in FIG. 1, this ceramic capacitor built-in wiring board 71 (wiring board) is formed by forming a buildup layer 73 on one side of a core board 72 made of glass epoxy. The build-up layer 73 includes four resin insulating layers 81, 82, 83, and 84 (so-called interlayer insulating layers) that are also made of an epoxy resin. On the interface between the core substrate 72 and the resin insulating layer 81, a conductor layer 90 made of copper is patterned. Conductor layers 91, 92, 93 made of copper are patterned at the interfaces between the resin insulating layers 81, 82, 83, 84. In addition, terminal pads 94 in which copper is coated with nickel-gold plating are formed at a plurality of locations on the surface of the outermost resin insulation layer 84. Each terminal pad 94 can be electrically connected to an IC chip 97 having a function as an MPU. Further, via conductors 96 are provided in the core substrate 72 and the resin insulating layers 81, 82, 83, 84, respectively. Most of these via conductors 96 are arranged on the same axis, and the conductor layers 91, 92, 93 and the terminal pads 94 are electrically connected to each other through them.

  As shown in FIG. 1, BGA pads 55 electrically connected to the via conductors 96 are formed in a lattice shape at a plurality of locations on the lower surface of the core substrate 72. Further, the lower surface of the core substrate 72 is almost entirely covered with the solder resist 52. An opening 53 for exposing the BGA pad 55 is formed at a predetermined position of the solder resist 52. On the surface of the BGA pad 55, a plurality of solder bumps 49 are provided for electrical connection with a mother board (not shown). The solder bump 49 is made of tin-lead solder having a composition of 90 Pb / 10 Sn.

  The ceramic capacitor built-in wiring board 71 shown in FIG. 1 is mounted on the mother board by the solder bumps 49. The ceramic capacitor built-in wiring board 71 of this embodiment is a BGA (ball grid array). The form of the wiring board 71 with a built-in ceramic capacitor is not limited to BGA alone, and may be, for example, LGA (land grid array), PGA (pin grid array), or the like.

  Inside the build-up layer 73 (specifically, the interface between the first resin insulating layer 81 and the second resin insulating layer 82) is the ceramic capacitor 10 (capacitor) shown in FIGS. It is implemented in an embedded state. The ceramic capacitor 10 is formed by a high dielectric constant material sheet 20 including a dielectric layer 21. A first metal electrode layer 11 (metal layer) made of copper plating is formed on the first main surface 117 of the dielectric layer 21, and a second metal made of copper plating is formed on the second main surface 118 of the dielectric layer 21. A metal electrode layer 31 (metal layer) is formed.

  The dielectric layer 21 includes a plurality of dielectric grains 22 and an interlayer insulating material 23. The dielectric grains 22 are made of a sintered body of barium titanate, which is a kind of high dielectric constant ceramic, and function as a dielectric between the first metal electrode layer 11 and the second metal electrode layer 31. On the other hand, the interlayer insulating material 23 is made of an epoxy resin which is a kind of organic resin material, and has a function of fixing the plurality of dielectric particles 22 to each other and insulating the plurality of dielectric particles 22 from each other. The interlayer insulating material 23 also functions as a dielectric between the first metal electrode layer 11 and the second metal electrode layer 31.

  As shown in FIGS. 1 to 3, the dielectric grains 22 are two-dimensionally arranged in a single layer along the planar direction of the dielectric layer 21. Specifically, the dielectric grains 22 are arranged in a lattice shape (array shape) along the planar direction of the dielectric layer 21. And the dielectric material part 24 is formed by arrange | positioning the interlayer insulation material 23 around each dielectric material grain 22. As shown in FIG. Thereby, in the dielectric part 24, the dielectric grains 22 and the interlayer insulating material 23 are alternately and regularly arranged along the planar direction of the dielectric layer 21. The dielectric portion 24 is a region where the dielectric particles 22 are densely packed, and is a region (see FIG. 3) having a rectangular shape when viewed from the thickness direction of the dielectric layer 21. Each dielectric particle 22 has a substantially spherical shape in which the degree of contour is equal to or less than the thickness of the first metal electrode layer 11 and the second metal electrode layer 31 (about 0.5 μm to 1.5 μm), and the particle size thereof is 30 μm. Is set to The distance (pitch) between the centers of the adjacent dielectric grains 22 is also set to 30 μm, which is the same as the grain diameter of the dielectric grains 22. For this reason, the dielectric grains 22 are in contact with each other. As shown in FIG. 3, the pitch between the dielectric grains 22 is equal both in the vertical direction (vertical direction in FIG. 3) and in the horizontal direction (horizontal direction in FIG. 3) of the ceramic capacitor 10.

In this embodiment, the volume ratio of the dielectric grains 22 in the dielectric portion 24 is 70%, which is larger than the volume ratio (30%) of the interlayer insulating material 23 in the dielectric portion 24. Moreover, the dielectric constant of the dielectric particles 22 is 3000, and the relative dielectric constant of the interlayer insulating material 23 is 3. Therefore, the relative dielectric constant of the interlayer insulating material 23 is relatively lower than the relative dielectric constant of the dielectric grains 22. The maximum thickness of the dielectric portion 24 is 30 μm, which is the same as the particle size of the dielectric particles 22. Therefore, the capacitance density of the dielectric part 24 in this embodiment is 0.056 μF / cm ² , and the capacitance coefficient of the dielectric part 24 in this embodiment is 168 pF / cm. The “capacitance coefficient” is the product of the capacitance density and the thickness of the dielectric portion 24.

  As shown in FIGS. 1 and 2, the particle size of each dielectric particle 22 is larger than the maximum thickness (about 20 μm) of the interlayer insulating material 23. For this reason, the upper end portion of each dielectric particle 22 protrudes from the first main surface 117, and the lower end portion of each dielectric particle 22 protrudes from the second main surface 118. As a result, irregularities are formed on both the first main surface 117 and the second main surface 118. Thereby, in the 1st main surface 117 and the 2nd main surface 118, the height difference of the protrusion part of the dielectric material grain 22 and the interlayer insulation material 23 is set to about 3 micrometers-7 micrometers. The thickness of the first metal electrode layer 11 and the second metal electrode layer 31 is set to about 30 μm. For this reason, the thickness of the entire ceramic capacitor 10 is about 90 μm, which is extremely thin.

  As shown in FIG. 1, since the first metal electrode layer 11 is in an upward state when mounted on the wiring board, the first metal electrode layer 11 is electrically connected to the via conductor 96 in the second resin insulating layer 82. On the other hand, since the second metal electrode layer 31 is in a downward state when mounted on the wiring board, the second metal electrode layer 31 is electrically connected to the via conductor 96 in the first resin insulating layer 81.

  Then, when the ceramic capacitor 10 having such a configuration is energized and a predetermined voltage is applied between the first metal electrode layer 11 and the second metal electrode layer 31, a positive charge is accumulated on one electrode, Negative charges accumulate on the electrodes. As a result, the ceramic capacitor 10 functions as a capacitor. In the present embodiment, the ceramic capacitor 10 has a function of removing noise and stabilizing the power to be supplied to the IC chip 97, and is involved in improving the operability of the IC chip 97.

  Next, a method for manufacturing the ceramic capacitor 10 will be described with reference to FIGS.

  First, a mesh member 100 (jig) as shown in FIGS. 4 and 5 is prepared, and a positioning step is performed. The mesh member 100 is configured by orthogonally crossing a plurality of metal wires arranged in parallel with each other along the vertical direction and a plurality of metal wires arranged in parallel with each other along the horizontal direction. The mesh member 100 has a plurality of positioning portions 101 arranged in a lattice shape along the plane direction (the jig main surface direction) of the mesh member 100. Each positioning portion 101 is a space (mesh) formed in a square shape by four metal wires, and the mesh width is smaller (about 25 μm) than the particle size (30 μm) of the dielectric particles 22. . For this reason, the dielectric particles 22 are reliably supported by the metal wire. In the present embodiment, a commercially available printing screen is used as the mesh member 100.

  In the positioning step, vacuuming is performed from one side of the mesh member 100 through the plurality of positioning portions 101, so that the plurality of dielectric particles 22 are fitted into the positioning portions 101. As a result, the plurality of dielectric particles 22 are held by the plurality of positioning portions 101, and each dielectric particle 22 is arranged in a lattice shape along the planar direction of the mesh member 100. In this embodiment, since the vacuuming is performed, the plurality of dielectric grains 22 can be quickly held by the plurality of positioning portions 101. In addition, it is possible to prevent displacement and dropout of each dielectric particle 22 due to vibration or the like.

  Next, a metal foil 111 (carrier material) as shown in FIG. 6 is prepared and a transfer process is performed. In addition, the metal foil 111 of this embodiment has the adhesion layer 112 on one side. The adhesion layer 112 is formed of an epoxy resin adhesive.

  In the transfer process, the adhesion layer 112 side of the metal foil 111 is disposed above the mesh member 100, and the adhesion layer 112 is brought into contact with the plurality of dielectric particles 22 positioned on the mesh member 100 (see FIG. 7). . In this state, a pressing force is applied in the vertical direction (downward in FIG. 7). As a result, each dielectric particle 22 is transferred onto the adhesion layer 112. At this time, since a part of the plurality of dielectric particles 22 is embedded in the adhesion layer 112, the contact area between each dielectric particle 22 and the adhesion layer 112 is increased, so that each dielectric particle 22 is more reliably secured. Can be positioned. Thereafter, a first curing step of heating at a predetermined temperature and for a predetermined time is performed, and the adhesion layer 112 is slightly cured by heat. As a result, each dielectric particle 22 is temporarily fixed to the metal foil 111 via the adhesion layer 112.

  Next, a fixing step is performed, and the plurality of dielectric particles 22 are fixed to each other with an interlayer insulating material 23 made of an epoxy resin. More specifically, a sheet-like interlayer insulating material 23 is disposed on the adhesion layer 112 side of the metal foil 111 onto which the plurality of dielectric grains 22 have been transferred (see FIG. 8), and in this state, the same direction as the vertical direction (see FIG. Apply a pressing force in the downward direction (8). Specifically, in this embodiment, a pressing force (0.7 MPa) is applied in the same direction as the vertical direction while heating to a temperature of 100 ° C. or higher under a vacuum of 20 Torr (≈2666 Pa) or less (vacuum heat press). Accordingly, the metal foil 111, the adhesion layer 112, each dielectric particle 22 and the interlayer insulating material 23 are pressed along the stacking direction, and the metal foil 111 and the interlayer insulation material 23 are joined (thermocompression bonding) via the adhesion layer 112. ) At this time, a part of the interlayer insulating material 23 enters between the dielectric grains 22 (see FIG. 9).

  Further, a second curing step of heating at a predetermined temperature and a predetermined time is performed to thermally cure the adhesion layer 112. As a result, the plurality of dielectric grains 22 are fixed to each other, and the respective dielectric grains 22 cannot be moved. Since the adhesion layer 112 is made of the same epoxy resin as the interlayer insulating material 23, it is integrated with the interlayer insulating material 23 by heat. As a result, the dielectric layer 21 is obtained (see FIG. 10).

After the fixing step, a first unevenness forming step (grain exposure step) is performed. Specifically, a part of the plurality of dielectric grains 22 is protruded from the interlayer insulating material 23 to form irregularities on the surface of the dielectric layer 21, and the surface is defined as a second main surface 118 (see FIG. 11). ). In this embodiment, the surface layer of the interlayer insulating material 23 is removed by performing surface grinding using a conventionally known buffing apparatus, lapping apparatus, polishing apparatus, blast apparatus, O ₂ plasma, etc. A part of the dielectric particles 22 is protruded from the interlayer insulating material 23. In addition, the protrusion amount of each dielectric particle 22 can be adjusted by changing the grinding time or changing the hardness of the abrasive.

  After the first unevenness forming step, a first metal layer forming step (metal layer forming step) is performed. Specifically, the electroless copper plating is performed on the second main surface 118 of the dielectric layer 21 based on a conventionally known technique, and then the electrolytic copper plating is further performed to form a second metal electrode having a thickness of about 30 μm. Layer 31 is formed directly (see FIG. 12). If the second metal electrode layer 31 is formed by electroless copper plating and electrolytic copper plating, a large amount of processing can be performed, so that the ceramic capacitor 10 can be manufactured at low cost.

  Next, a core substrate 72 on which a conductor layer 90 and a first resin insulation layer 81 are formed is prepared, and a dielectric with the second metal electrode layer 31 facing downward on the first resin insulation layer 81 is prepared. The body layer 21 is mounted (see FIG. 13). At the time of mounting, the ceramic capacitor 10 of the present embodiment is an intermediate product before completion.

  More specifically, an uncured film material for forming the first resin insulation layer 81 is prepared, and is pasted on the surface of the core substrate 72 with a laminator or the like. As said film material, what consists of uncured thermosetting resin is suitable, for example. Next, the dielectric layer 21 in the state of FIG. 13 is mounted on the film material and pressed with a predetermined pressure. At this time, since the film material is still uncured, a part of the dielectric layer 21 can be easily embedded in the film material. Next, heating is performed to cure the film material, and the intermediate product of the ceramic capacitor 10 is supported and fixed to the first resin insulating layer 81.

  Next, the metal foil 111 is removed by etching or the like (see FIG. 14), and a second unevenness forming step (grain exposure step) is performed. Specifically, the same process as the first unevenness forming process (surface grinding in this embodiment) is performed. That is, a part of the plurality of dielectric grains 22 is protruded from the interlayer insulating material 23 to form irregularities on the surface of the dielectric layer 21, and the surface is used as the first main surface 117 (see FIG. 15).

  Next, a second metal layer forming step (metal layer forming step) is performed. Specifically, electroless copper plating is performed on the first main surface 117 of the dielectric layer 21 based on a conventionally known method, and then electrolytic copper plating is further performed to form a first metal electrode having a thickness of about 30 μm. Layer 11 is formed directly (see FIG. 16). The ceramic capacitor 10 of this embodiment is completed at this point.

  Thereafter, the conductor layer 91 in the first resin insulation layer 81 is formed in accordance with a conventionally known method. Next, the above-mentioned uncured film material is pasted on the first resin insulating layer 81 with a laminator or the like, and then thermally cured to form the second resin insulating layer 82. At this point, the ceramic capacitor 10 is completely embedded.

  Next, after drilling a via hole in the second resin insulating layer 82, further filling with copper plating or copper paste and printing to form a via conductor 96 and a second conductor layer 92 are formed. To do.

  Thereafter, the resin insulation layers 83 and 84 of the third layer and the fourth layer (the outermost layer) are formed by the same method, and the BGA pad 55 is formed on the lower surface side of the core substrate 72 according to a conventionally known method. A solder resist 52 and solder bumps 49 are formed. As a result, the ceramic capacitor built-in wiring board 71 of FIG. 1 is completed.

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

  (1) In general, in a conventional ceramic capacitor, dielectric grains 22 having a relatively high relative dielectric constant and interlayer insulating material 23 having a relatively low relative dielectric constant are formed in the thickness direction of the dielectric layer 21. (See, for example, the relationship between the dielectric particles 124 and the interlayer insulating material 125 shown in FIG. 31).

  In this case, the relative dielectric constant ε1 of the entire ceramic capacitor can be obtained from the equation 1 / ε1 = V1 × 1 / ε2 + V2 × 1 / ε3. Here, ε2 is the relative dielectric constant of the dielectric particles 22, ε3 is the relative dielectric constant of the interlayer insulating material 23, V1 is the volume ratio (%) of the dielectric particles 22 in the dielectric portion 24, and V2 is This is the volume ratio (%) of the interlayer insulating material 23 in the dielectric portion 24.

  However, for example, even when the relative dielectric constant ε1 is calculated by setting the relative dielectric constant ε2 to 3000, the relative dielectric constant ε3 to 3, the volume ratio V1 to 70%, and the volume ratio V2 to 30%, ε1 = 10.0 is obtained. The rate ε1 is not so high.

  On the other hand, in the ceramic capacitor 10 of the present embodiment, the dielectric grains 22 and the interlayer insulating material 23 exist in parallel along the thickness direction of the dielectric layer 21. Therefore, the dielectric grains 22 and the interlayer insulating material 23 do not exist in series along the thickness direction of the dielectric layer 21.

  In this case, the relative dielectric constant ε1 of the entire ceramic capacitor 10 is obtained from the equation ε1 = V1 × ε2 + V2 × ε3 (from Nielsen's compound law). Here, if the relative permittivity ε1 is calculated under the same conditions as in the prior art, ε1 = 70 (%) × 3000 + 30 (%) × 3 = 2100.9, so the relative permittivity ε1 is considerably higher than in the prior art. Become. Therefore, it is easy to increase the capacity of the ceramic capacitor 10 of this embodiment.

  (2) The dielectric particles 22 of the present embodiment are substantially spherical. Therefore, since the plurality of dielectric grains 22 can be easily aligned, the ceramic capacitor 10 can be easily manufactured. Further, when the ceramic capacitor 10 is manufactured, it is not necessary to consider the orientation of the dielectric particles 22 when the dielectric particles 22 are held on the positioning portion 101 of the mesh member 100. Therefore, the ceramic capacitor 10 can be manufactured efficiently.

  (3) In the present embodiment, the ceramic capacitor 10 is embedded in the ceramic capacitor built-in wiring board 71, and the IC chip 97 is mounted on the upper surface of the ceramic capacitor built-in wiring board 71. The ceramic capacitor 10 and the IC chip 97 are electrically connected to each other. Connected. As a result, the length of the wiring connecting the ceramic capacitor 10 and the IC chip 97 is shortened, so that the signal speed between the ceramic capacitor 10 and the IC chip 97 can be increased.

(4) In the manufacturing method of the ceramic capacitor 10 (high-dielectric-constant material sheet 20) of the present embodiment, a process that has been essential in the past (for example, a process of firing a green sheet containing an unsintered dielectric material for a predetermined time) It is not necessary to carry out. Therefore, the ceramic capacitor 10 can be manufactured efficiently.
[Second Embodiment]

  Next, the manufacturing method of the ceramic capacitor 10 of 2nd Embodiment is demonstrated based on FIGS. Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

  The manufacturing method of this embodiment is different from the manufacturing method of 1st Embodiment by the point which uses the resin film 113 (carrier material) shown, for example in FIG. In the present embodiment, the resin film 113 is a commercially available adhesive tape having an adhesive layer 114 (adhesion layer) on one side.

  First, in the transfer step, the plurality of dielectric particles 22 are transferred onto the adhesive layer 114 of the resin film 113. (See FIG. 18). At this time, some of the plurality of dielectric particles 22 are embedded in the adhesive layer 114. Next, a fixing process is performed, and the plurality of dielectric grains 22 are fixed to each other with the interlayer insulating material 23. More specifically, a sheet-like interlayer insulating material 23 is disposed on the adhesive layer 114 side of the resin film 113 to which a plurality of dielectric grains 22 are transferred (see FIG. 19), and a bonding force is applied while heating in this state. . Thereby, the resin film 113 and the interlayer insulating material 23 are bonded (thermocompression bonding) via the adhesive layer 114. At this time, a part of the interlayer insulating material 23 enters between the dielectric grains 22 (see FIG. 20). Furthermore, when a curing step of heating at a predetermined temperature and for a predetermined time is performed to thermally cure the interlayer insulating material 23, the plurality of dielectric particles 22 are fixed to each other, and the dielectric layer 21 is obtained.

  After the fixing step, a first unevenness forming step (grain exposure step) is performed, and a part of the plurality of dielectric grains 22 is protruded from the interlayer insulating material 23 (see FIG. 21). Further, after the first unevenness forming step, the first metal layer forming step (metal layer forming step) is performed to directly form the second metal electrode layer 31 on the second main surface 118 of the dielectric layer 21 (FIG. 22). reference).

  Next, a core substrate 72 on which a conductor layer 90 and a first resin insulation layer 81 are formed is prepared, and a dielectric with the second metal electrode layer 31 facing downward on the first resin insulation layer 81 is prepared. The body layer 21 is mounted (see FIG. 23). Next, a 2nd uneven | corrugated formation process (grain exposure process) is implemented. Specifically, a step different from the first unevenness forming step is performed. That is, by peeling the resin film 113, a part of the plurality of dielectric particles 22 is protruded from the interlayer insulating material 23 (see FIG. 24). In addition, since the adhesive layer 114 of this embodiment is made of a material whose adhesive strength is reduced by heat (Intellimer manufactured by Nitta Corporation) and the adhesive strength is reduced when the curing process is performed, the resin film 113 is used. Can be easily peeled off.

  Next, a second metal layer forming step (metal layer forming step) is performed to directly form the first metal electrode layer 11 on the first main surface 117 of the dielectric layer 21 (see FIG. 25). As a result, the ceramic capacitor 10 is completed. Thereafter, the second to fourth (outermost) resin insulation layers 82, 83, 84, etc. are formed in accordance with a conventionally known technique, thereby completing the ceramic capacitor built-in wiring board 71 of FIG.

  Therefore, according to the manufacturing method of the present embodiment, each dielectric particle 22 can be more reliably prevented from moving because the adhesive layer 114 continues to hold each dielectric particle 22 even when the curing process is performed. Therefore, since the plurality of dielectric grains 22 can be fixed at a desired position, the ceramic capacitor 10 having excellent reliability can be manufactured. Further, in the second unevenness forming step, a part of each dielectric particle 22 can be protruded from the interlayer insulating material 23 simply by peeling off the resin film 113, so that the ceramic capacitor 10 can be manufactured efficiently. Furthermore, it is not necessary to perform etching or the like when removing the resin film 113. Therefore, since the number of steps is reduced, the manufacturing cost of the ceramic capacitor 10 can be reduced.

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

  In the above embodiment, a part of the plurality of dielectric grains 22 protrudes from both the first main surface 117 and the second main surface 118. However, a part of each dielectric grain 22 may protrude from one of the first main surface 117 and the second main surface 118, or may protrude from the first main surface 117 and the second main surface 118. It does not have to be.

  -Although the dielectric particle 22 of the said embodiment was substantially spherical shape, you may make the dielectric particle 22 non-spherical shape (For example, substantially columnar shape as shown in FIG. 26, for example). In this case, a part of the plurality of dielectric grains 22 may protrude from either the first main surface 117 or the second main surface 118, or the first main surface 117 and the second main surface 118 You may make it protrude in both (FIG. 27).

  -The mesh member 100 of the said embodiment has the some positioning part 101 arranged in the grid | lattice form along the plane direction of the mesh member 100, and the some dielectric particle 22 follows the plane direction of the mesh member 100. It was arranged in a grid. However, as shown in FIG. 28, the plurality of positioning portions 101 are arranged in a zigzag pattern along the plane direction of the mesh member 100, and the plurality of dielectric particles 22 are arranged in a zigzag pattern along the plane direction. You may do it. By doing so, the gap between the plurality of dielectric particles 22 becomes smaller, so that the volume ratio of the dielectric particles 22 becomes even larger than the volume ratio of the interlayer insulating material 23. Therefore, the capacitance of the ceramic capacitor 10 can be further increased.

  In the above embodiment, the mesh member 100 having a mesh smaller than the particle diameter of the plurality of dielectric particles 22 is used as a jig used in the positioning step. However, a vacuum chuck 102 as shown in FIGS. 29 and 30 may be used as a jig. The vacuum chuck 102 includes a plurality of dielectric particle holding recesses 103 (positioning portions) that support the plurality of dielectric particles 22. The dielectric particle holding recesses 103 are arranged in a lattice pattern along the support surface 104 (jig main surface). A vacuum pulling path 105 communicates with the dielectric particle holding recess 103, and the dielectric particles 22 are attracted and held in the dielectric particle holding recess 103 by performing vacuuming through the vacuum pulling path 105. The vacuum chuck 102 can be manufactured by a conventionally known semiconductor manufacturing process.

  The shape of the dielectric particle holding recess 103 is preferably set as appropriate in accordance with the shape of the dielectric particle 22. For example, when the dielectric particle 22 is substantially spherical, the dielectric particle holding recess 103 is preferably formed in a mortar shape (see FIG. 29). When the dielectric particles 22 are substantially columnar, the dielectric particle holding recesses 103 are preferably formed in a substantially U-shaped cross section (see FIG. 30).

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

  (1) A high dielectric constant material sheet comprising a dielectric layer having a first main surface and a second main surface, wherein the dielectric layer is two-dimensionally and single along the planar direction of the dielectric layer. A high dielectric constant material sheet comprising a plurality of dielectric grains arranged in layers and an organic resin material that fixes the plurality of dielectric grains together.

  (2) The dielectric layer comprising: a dielectric layer having a first main surface and a second main surface; and an electrode formed on one of the first main surface and the second main surface. Has a plurality of dielectric grains arranged two-dimensionally and in a single layer along the planar direction of the dielectric layer, and an organic resin material that fixes the plurality of dielectric grains together. Wiring board embedded capacitor.

The schematic sectional drawing which shows the ceramic capacitor built-in wiring board of this invention. The schematic sectional drawing which shows the ceramic capacitor of this invention. The top view which shows the ceramic capacitor of this invention. Sectional drawing which shows a part of mesh member and dielectric material grain. The top view which shows a mesh member. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 1st Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing for demonstrating the manufacturing method of 2nd Embodiment. The schematic sectional drawing which shows the ceramic capacitor of other embodiment. The schematic sectional drawing which shows the ceramic capacitor of other embodiment. The top view which shows the mesh member of other embodiment. The schematic sectional drawing which shows the vacuum chuck of other embodiment. The schematic sectional drawing which shows the vacuum chuck of other embodiment. The schematic sectional drawing which shows the capacitor of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Ceramic capacitor as a capacitor 11 ... 1st metal electrode layer 20 as a metal layer ... High dielectric material sheet 21 ... Dielectric layer 22 ... Dielectric grain 23 ... Interlayer insulating material 31 as material and organic resin material ... Metal Second metal electrode layer 71 as a layer ... Ceramic capacitor built-in wiring substrate 100 as a wiring substrate ... Mesh member 101 as a jig ... Positioning portion 102 ... Vacuum chuck 103 as a jig ... Dielectric grain holding concave portion as a positioning portion DESCRIPTION OF SYMBOLS 104 ... Support surface 111 as a jig | tool main surface ... Metal foil 112 as a carrier material ... Adhesion layer 114 ... Adhesive layer 113 as an adhesion layer ... Resin film 117 as a carrier material ... 1st main surface 118 ... 2nd main surface

Claims (14)

  A high dielectric constant material sheet comprising a dielectric layer having a first main surface and a second main surface, wherein the dielectric layer is arranged two-dimensionally and in a single layer along the planar direction of the dielectric layer A high dielectric constant material sheet comprising a plurality of dielectric particles and a material for fixing the plurality of dielectric particles together.   2. The high dielectric constant material according to claim 1, wherein a part of the plurality of dielectric grains is exposed on at least one of the first main surface and the second main surface. Sheet.   2. The high dielectric constant material sheet according to claim 1, wherein a part of the plurality of dielectric grains is exposed on both the first main surface and the second main surface.   The high dielectric constant material sheet according to any one of claims 1 to 3, wherein the plurality of dielectric grains are substantially spherical.   5. The high dielectric constant material sheet according to claim 1, wherein a particle diameter of the plurality of dielectric particles is 10 μm or more and 50 μm or less.   The high dielectric constant material sheet according to any one of claims 1 to 5, wherein the plurality of dielectric grains are made of a perovskite oxide.   The high dielectric constant according to claim 1, further comprising a metal layer directly formed on at least one of the first main surface and the second main surface. Material sheet.   8. The carrier material according to claim 1, further comprising a carrier material attached to at least one of the first main surface and the second main surface to protect the dielectric layer. High dielectric constant material sheet.   The high dielectric constant material sheet according to any one of claims 1 to 8, wherein the high dielectric constant material sheet is a material for forming a capacitor.   A wiring board comprising the high dielectric constant material sheet according to claim 1 embedded therein. A jig having a structure in which a plurality of positioning portions are two-dimensionally arranged along the jig main surface is prepared, and the plurality of dielectric particles are held by holding the plurality of dielectric particles in the plurality of positioning portions. A positioning step to arrange two-dimensionally and in a single layer along the jig main surface;
Preparing a carrier material having an adhesion layer, and transferring the plurality of dielectric particles positioned on the jig onto the adhesion layer;
A method of manufacturing a high dielectric constant material sheet, comprising: a fixing step of fixing the transferred plurality of dielectric particles with an organic resin material to form a dielectric layer.   The method for manufacturing a high dielectric constant material sheet according to claim 11, wherein the jig used in the positioning step is a mesh member having a mesh smaller than a particle size of the plurality of dielectric particles.   The method for producing a high dielectric constant material sheet according to claim 11, further comprising a metal layer forming step of directly forming a metal layer on the dielectric layer after the fixing step.   14. The method of manufacturing a high dielectric constant material sheet according to claim 13, further comprising a grain exposing step of exposing a part of the plurality of dielectric grains after the fixing step and before the metal layer forming step. .

Images