JP2007149757A - Composite electronic component, and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite electronic component structured of a composite porous thin material, comprising a porous material with a resin impregnated and excellent in flexibility used as a magnetic substrate. <P>SOLUTION: The composite electronic component 100 includes the composite porous material, and a conductive pattern 20 formed on the surface of the composite porous material. The conductive pattern 20 is formed, for example, by selectively removing a metallic foil formed entirely on the surface of the porous material by a method such as etching. The conductive pattern 20 is spiral for example, and has a terminal electrode formed at a terminal end. The composite porous material has a structure in which a porous material body 1 and the metallic foil 4 are laminated. The body 1 is constituted of a particulate structure 2 and a resin phase 3. The particulate structure 2 has a structure in which a plurality of particles P are bonded with one another. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a composite electronic component and a manufacturing method thereof, and more particularly to an antenna and other composite electronic components configured using a magnetic substrate and a manufacturing method thereof.

  In recent years, electronic devices using high frequencies such as digital electronic devices have been widely used. In particular, mobile communication devices using a quasi-microwave band have been widely used. For example, mobile phones and the like have become smaller and lighter. The demand for is strong. As a result, electronic components are being developed in the direction of high-density mounting. However, under such high-density mounting, electromagnetic coupling between components and wiring often prevents normal operation of the device. In a personal computer or the like, radiation noise is likely to be generated due to the increase in the clock, and such noise is likely to have an adverse effect on peripheral parts and peripheral devices and needs to be dealt with.

  In order to cope with these problems, for example, in Patent Document 1, in a reader / writer antenna in an RFID system, a soft magnetic material is interposed between an antenna coil and a metal surface of a conductive article such as a metal case in which the antenna coil is installed. There has been proposed a method of blocking the magnetic flux entering the conductive article and suppressing the influence by providing the material or the conductive material (see Patent Document 1).

  Further, in Patent Document 2, a coil body made of a conductor wound in a plane in a plane, and one end is located in the central portion surrounded by the coil body, and the other end crosses a part of the coil body. There has been proposed a tag antenna coil including a plate-like or sheet-like magnetic core member bonded to one surface of a coil body so as to be located outside the body (see Patent Document 2). According to the tag antenna coil, since the magnetic core member is bonded across a part of the coil body, the Q value of the antenna coil can be increased. Also, the magnetic flux generated by the current flowing in the coil body formed by the conductor draws a loop passing through the magnetic core member, and the direction of the magnetic flux is parallel to the surface of the article. Even if this tag antenna coil is attached, the eddy current generated in the metal on the surface of the article is suppressed, and the antenna coil can be operated reliably.

  Furthermore, a composite magnetic sheet in which magnetic powder is dispersed and mixed in rubber or resin has been put into practical use as a radio wave absorber. These composite magnetic sheets are known to have a high magnetic permeability in order to obtain high radio wave absorption performance.

  As a magnetic material used for these composite magnetic sheets, a flattened metal magnetic powder is often used. The reason for using the flattened magnetic filler is that by arranging the fillers in a certain direction, it is considered that the magnetic permeability can be increased because the demagnetizing field coefficient in that direction can be reduced, This is because such a result is actually shown. The reason for the metal magnetic powder is that it can be flattened by an attritor or a ball mill. With ceramic powders such as ferrite, the particles are shattered and cannot be flattened.

  Among the above-mentioned radio wave absorbers, there are those using a magnetic material and those using a dielectric compounded with carbon. In radio wave absorbers, the permittivity as well as the permeability affects the reflection coefficient of the electromagnetic interface and the wavelength inside the absorber, so it is necessary to lower the dielectric constant of ferrite for the purpose of obtaining desired characteristics There is. In such a situation, as a method of lowering the apparent dielectric constant without relatively lowering the magnetic permeability, a porous magnetic material is used, or a material impregnated with resin or glass is used to improve strength. It has been proposed (for example, Patent Document 3). Patent Document 3 forms a blended magnetic material for a magnetic sintered body in which a magnetic material, a binder, and a burned-out material having a spherical or granular form and having adhesion to the binder are formed. After firing the sinter to form a magnetic sintered body containing 10 to 80% by volume of pores, the pores of the magnetic sintered body are filled with resin or glass, thereby realizing a low dielectric constant and water absorption. Low and secures mechanical strength.

JP 2004-166175 A JP 2003-108966 A JP 2004-146801 A

  The composite magnetic material disclosed in Patent Document 3 is exclusively assumed to be a radio wave absorber, and is fired after laminating ceramic green sheets with a thickness of about 100 μm produced by the doctor blade method to a thickness of about 2 mm. ing. If it is such a thickness, it can be fired sufficiently, but there is a demand for a thin composite magnetic material of, for example, 100 μm or less, and further 50 μm or less. Not easy to get. Moreover, even if it can be fired, the flexibility is insufficient and handling is not easy.

  The present invention has been made on the basis of such a technical problem, and is configured using a composite porous body having a thin thickness and excellent in flexibility made of a porous body impregnated with a resin as a magnetic substrate. Another object of the present invention is to provide a composite electronic component and a method for manufacturing the same.

  In order to achieve the above-mentioned object, the present inventors examined the formation of a porous body on a metal foil. This is because the metal foil becomes a support and it is easy to obtain a sound porous body. However, when sintering was performed in order to obtain a porous body on a metal foil, a crack occurred in the sintered body. This is considered to be due to the limited shrinkage that occurs during the sintering process due to the presence of the support. Accordingly, when the formation of the neck, which is the initial stage of so-called sintering, was limited, it was possible to obtain a sound particle structure and a composite porous body that exhibited the physical properties of the particles. .

  The present invention is based on the above knowledge, and the object of the present invention is to provide a composite porous body and at least a conductive pattern formed on the surface of the composite porous body. It is achieved by a composite electronic component comprising: a particle structure having pores connected by a neck and having pores communicating with the outside; and a resin phase filled in the pores of the particle structure .

  In the present invention, the particle structure preferably has a network structure in which the particles are continuous. Moreover, it is preferable that the porosity of the particle structure is 20 to 80%.

  In the present invention, the conductive pattern may be formed in a spiral shape or a helical shape. The conductive pattern thus configured can be used as an antenna coil.

  The composite electronic component of the present invention further includes a passive element electrically connected to the conductive pattern, and the passive element is preferably mounted on the front surface or the back surface of the composite porous body. Such a composite electronic component can be used as an antenna module.

  The composite electronic component of the present invention preferably further includes a semiconductor IC chip electrically connected to the conductive pattern. Here, the semiconductor IC chip may be mounted on the front surface or the back surface of the composite porous body, or may be mounted in a cavity formed in the composite porous body. It may be embedded. Such a composite electronic component can be used as a more sophisticated antenna module.

  Thus, the composite electronic component of the present invention is preferably an antenna device. This is because the magnetic permeability of the substrate made of the composite porous body is very high, and the influence of noise on the antenna can be sufficiently suppressed. In addition, the conductive pattern of the antenna can be formed on a very thin and flexible substrate, and various chip components can be mounted, which contributes to the reduction in size and thickness of the electronic device on which the antenna device is mounted. . In addition, since the handling property is good and the flexibility thereof is high, the antenna can be placed in close contact with the housing surface of the electronic device which is not flat, and the degree of freedom in design can be increased.

  The above object of the present invention also includes a step of applying a paint obtained by dissolving and dispersing at least magnetic particles and a binder in a solvent to a metal foil, and a debinding process of the paint applied to the metal foil. A step of forming a particle structure by performing a binding treatment of the particles of the magnetic material, a step of laminating a resin on the particle structure, and the particle structure by pressurizing the resin while heating It is also achieved by a method of manufacturing a composite electronic component, comprising: impregnating a body with the resin and curing; and forming a conductive pattern on a surface of the particle structure impregnated with the resin. The

  In the present invention, it is preferable that the step of forming the conductive pattern includes a step of selectively removing the conductive film formed on the surface of the particle structure.

  According to the present invention, since a magnetic particle structure impregnated with a resin is formed on a conductive metal substrate, a thin, flexible, and highly magnetic substrate can be provided. Similarly, antennas and other composite electronic components using such a substrate are also thin and sufficiently flexible, and the influence of radiation noise can be reduced.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic external perspective view showing the configuration of the composite electronic component according to the first embodiment of the present invention.

  As shown in FIG. 1, the composite electronic component 100 includes a composite porous body 10 and a conductive pattern 20 formed on the surface of the composite porous body 10. The conductive pattern 20 is formed, for example, by selectively removing the metal foil formed on the entire surface of the composite porous body 10 by a method such as etching. The conductive pattern 20 of this embodiment has a spiral shape, and a terminal electrode 20a is formed at the end portion. The conductive pattern 20 thus formed can be used as an antenna coil for RFID, for example.

  FIG. 2 is a side sectional view of the composite electronic component taken along the line AA in FIG.

  As shown in FIG. 2, the composite porous body 10 has a structure in which a porous body 1 and a metal foil 4 are laminated. The porous body 1 is composed of a particle structure 2 and a resin phase 3.

  The particle structure 2 has a structure in which a plurality of particles P are bonded to each other. That is, the particle structure 2 has a network structure in which the particles P are continuous. Although mentioned later in detail, the coupling | bonding of particle | grains P can be obtained by heating and hold | maintaining to predetermined temperature. This heating and holding is performed under mild conditions as compared with the firing conditions for obtaining a dense sintered body from the particles P. Minor conditions include the case where the heating temperature is low or the holding time is short. The particle structure 2 is a porous body having open pores that communicate with the outside. However, when viewed microscopically, there is no denying the existence of closed pores. The porosity of the particle structure 2 is preferably 20 to 80 vol% (volume%). If the porosity is less than 20 vol%, the amount of resin filled in the pores is insufficient, and it becomes difficult to impart sufficient flexibility to the composite porous body 10. On the other hand, if the porosity exceeds 80 vol%, the amount of particles P made of a magnetic material is insufficient, and it becomes difficult to obtain desired magnetic characteristics. A more preferable porosity is 25 to 70 vol%, and a further preferable porosity is 30 to 65 vol%. Moreover, even if the particle structure 2 of the present invention has a thickness of 100 μm or less, and even a thickness of 50 μm or less, the generation of cracks can be prevented.

  The resin phase 3 is composed of a resin material filled in the pores of the particle structure 2. The resin material can be filled in the pores of the particle structure 2 by impregnation. Since the pores of the particle structure 2 are open pores, the resin material filled therein forms a continuous path in the particle structure 2.

  By the way, as a composite material having flexibility, for example, a material in which high magnetic permeability oxide magnetic particles (filler) are dispersed in a resin is known. In this composite material, the magnetic oxide particles are dispersed in the resin, and the non-magnetic material resin is present between most of the oxide magnetic particles, so the magnetic permeability of the oxide magnetic particles cannot be utilized. Will have a low magnetic permeability. In order to reduce the demagnetizing factor, it is conceivable to use metal magnetic particles having a high magnetic permeability, but the insulation in the composite material is lowered, which makes it difficult to use practically. Further, it is conceivable to increase the permeability of the composite material by increasing the filling amount of the oxide magnetic particles. However, the material itself becomes fragile, causing defects during the process due to cracks and the like. Therefore, there is a limit to increasing the filling amount.

  On the other hand, the composite porous body 10 according to the present embodiment includes the particle structure 2 having the network-like structure in which the particles P are bonded. Therefore, when the particles P are made of a magnetic material, In addition, the magnetic permeability can be increased by reducing the demagnetizing factor.

  In addition, it is difficult to achieve flexibility with the particle structure 2 alone, but it is possible to give a predetermined flexibility by filling the pores with resin. Forming the porous body 1 on the metal foil 4 as the first conductive metal substrate also contributes to the flexibility, particularly the flexibility required during the manufacturing process. This point will be further described in the description of the method for manufacturing the composite porous body 10 described later.

(Particle P)
The particles P can be made of a magnetic material. Magnetic materials include Ni—Zn, Mg—Zn, Mn—Zn, Cu—Zn, Cu—Zn—Mg, Mn—Mg, Mn—Mg—Zn, and Ni—Cu—Zn. It can be composed of a known ferrite material such as ferrite and hexagonal ferrite suitable for high frequency use. As a magnetic body, not only the above oxide but a metal magnetic body can be used. As the metal magnetic body, Fe, Ni, Co, and alloys thereof can be widely used. For example, an Fe—Ni alloy, an Fe—Co alloy, an Fe—Ni—Co alloy, and an Fe—Si alloy.

  The above particles P preferably have a particle size in the range of 0.1 to 10 μm, and more preferably in the range of 0.3 to 3 μm. The content of the particles P is preferably in the range of 20 to 80 vol%, more preferably 30 to 75 vol%, when the total of the filling resin and the particles P described later is 100 vol%, and more preferably 30 to 75 vol%. More preferably, it is 70 vol%.

(Filling resin)
As the resin filled in the pores of the particle structure 2, both thermoplastic resin and thermosetting resin can be used. Specifically, epoxy resin, phenol resin, vinyl benzyl ether compound resin, bis There are maleimide triazine resins, cyanate ester resins, polyimides, polyolefin resins, polyesters, polyphenylene oxides, liquid crystal polymers, silicone resins, fluorine resins, and the like, and these can be used alone or in combination. Moreover, when the form of the composite porous body 10 constitutes a sheet or film, it goes without saying that the above materials can be used, but other than that, a rubber material such as acrylic rubber or ethylene acrylic rubber or a rubber component is used. It may be a resin material that partially contains. The resin to be filled does not necessarily need to be liquid, and any resin that melts by heating can be used. Resins that are difficult to dissolve in solvents, such as high heat resistance resins called super engineering plastics, can also be used. As described above, according to the present invention, since there are a wide range of choices of the resin to be filled, various characteristics such as improvement in heat resistance can be dealt with.

(Metal foil 4)
As the metal foil 4 as the first conductive metal substrate, a copper foil, a nickel foil, an aluminum foil, a gold foil, an alloy foil containing a plurality of these metal elements, and a clad foil of these and other metals can be used. . Here, the clad foil is a foil in which a dissimilar material metal is bonded together, for example, a copper foil in which nickel is bonded. The clad foil may be combined with any metal as long as it can be bonded. Although the present invention can use a foil made of a noble metal such as gold, it is preferable to use a base metal in terms of cost. The foil may be produced by electrolysis or produced by rolling. The thickness of the metal foil 4 is generally 500 μm or less, but is preferably 100 μm or less, particularly 50 μm or less in order to obtain a thin composite porous body 10. Metal foil 4 according to the present embodiment has an oxide film formed on the surface thereof. Due to the presence of the oxide film, it is possible to ensure the bonding force with the porous body body 1 made of an oxide. The metal foil 4 can function as a conductive path when the composite porous body 10 is used as an electronic component.

  In the composite porous body 10, the second conductive metal substrate can be laminated on the surface of the particle structure 2 on which the metal foil 4 is not laminated. The second conductive metal substrate may be affixed with a metal foil 4 or may be a metal film formed by a thin film formation process such as plating, sputtering, or vapor deposition. As the metal film, the same film as the metal foil 4 can be used. As the metal film, a metal film formed by plating, sputtering, vapor deposition, or CVD is used. Examples of the metal film formed by plating include copper, nickel, gold, silver, tin, and alloys containing them. Examples of the metal film formed by sputtering include copper, nickel, gold, silver, aluminum, tungsten, molybdenum, chromium, titanium, tin, and alloys containing them. Examples of the metal film formed by vapor deposition include copper, nickel, gold, silver, aluminum, tungsten, molybdenum, chromium, titanium, and tin. Examples of the metal film formed by CVD include copper, nickel, gold, and the like and alloys containing them. In addition, a metal film can be formed using metal nanopaste.

  As described above, according to the present embodiment, the composite porous body 10 excellent in flexibility including the porous main body 1 having a small thickness and impregnated with a resin is used as a substrate for an electronic component. Since it is used, the influence of radiation noise can be sufficiently suppressed, and a composite electronic component that is very thin and easy to handle can be realized.

  Next, a method for manufacturing the composite electronic component 100 configured as described above will be described. In the manufacture of the composite electronic component 100, the composite porous body 10 is first manufactured.

FIG. 3 is a diagram illustrating a manufacturing process of the composite porous body 10.
(Paint preparation)
In the production of the composite porous body 10, first, the particles P, the binder resin and the resin powder are dissolved and dispersed in a solvent to prepare a paint. Here, the resin powder is for forming pores in the particle structure 2 as will be described later, and the addition amount and particle size are appropriately determined depending on the porosity to be obtained. However, the resin powder is not an essential element in the present invention, and it is possible to form pores in the particle structure 2 without the resin powder by appropriately controlling the heating conditions. A dispersant, a plasticizer, etc. may be added to the paint.

  Here, the resin powder only needs to be decomposable at the time of binder removal described later, and is made of, for example, crosslinked polystyrene, crosslinked acryl, crosslinked methyl methacrylate, nylon, or the like. Moreover, the resin powder should just have solvent resistance of the grade which does not melt | dissolve in the solvent used in the coating-material raw material containing particle | grains P and binder resin. Such resin powder may be hollow.

  The method for producing the paint is the same as that for producing a paint for producing a green sheet used for producing a general ceramic substrate. The paint is produced using a paint producing apparatus. As the coating material preparation device, a general device such as a ball mill or a bead mill can be used.

(Coating)
Next, using a known method such as a doctor blade method, a gravure printing method, a screen printing method or the like, the prepared paint is applied and dried on the metal foil 4 to form a coating film 5 on the metal foil 4. .

(Binder removal)
Subsequently, a binder removal process is performed on the sheet on which the coating film 5 is formed on the metal foil 4. The binder removal is performed to remove the binder resin and resin powder contained in the coating film 5. The binder removal may be maintained at a temperature of about 300 to 600 ° C. for a predetermined time. In addition, it is preferable to implement a binder removal in the temperature rising process of the particle | grain bonding process of the following process. Moreover, voids (open holes) are formed between the particles P by removing the binder resin and the resin powder.

  The atmosphere in which the binder is removed should be selected depending on the material of the particles P. That is, when the particles P are oxides, it is recommended that the binder removal treatment be performed in an oxidizing atmosphere to oxidize the metal foil 4. Generally, an oxide and a metal do not react by heating. Therefore, by oxidizing the surface of the metal foil 4, the bonding between the particle structure 2 made of an oxide and the metal foil 4 is promoted in the next particle bonding process. However, the treatment in the oxidizing atmosphere is preferably performed so that the surface layer portion of the metal foil 4 is oxidized. This is because the metal foil 4 functions as a conductive layer. Examples of the oxidizing atmosphere include air, an inert gas containing oxygen having a predetermined partial pressure, and the like. When the particles P are made of a metal instead of an oxide, it is recommended that the binder be removed in an inert gas atmosphere because the bonding with the metal foil 4 is promoted by heating. This is for preventing oxidation of the metal foil 4.

(Particle binding treatment)
After the binder removal, processing for binding the particles P (particle binding processing) is performed. The temperature and atmosphere of the particle bonding treatment are performed under conditions suitable for the material constituting the particles P to be bonded. A general processing temperature is 600 to 1200 ° C. The atmosphere for the particle binding treatment is preferably an atmosphere in which the metal foil 4 is not oxidized. For example, an inert gas atmosphere such as a nitrogen gas atmosphere or an argon gas atmosphere may be used.

  In the particle bonding process, the particle structures 2 are formed on the metal foil 4 by the particles P reacting with each other in the contact region. In the particle structure 2, vacancies formed between the particles P by the binder removal remain.

As a condition for the particle binding treatment, it should be avoided that the particles P are completely diffused and reacted with each other, and it is sufficient that the reaction is such that the particles P can form a continuum. That is, the conditions may be such that neck formation occurs between the particles P. Needless to say, a glass component may be added to accelerate the particle bonding treatment. By using the glass component, the temperature of the particle bonding process can be lowered or the processing time can be shortened. As the glass component, either a crystallized glass or an amorphous glass can be used as long as it is a general glass. Examples thereof include those containing SiO ₂ , Al ₂ O ₃ , RO (R is Mg, Ca, Sr, Ba), specifically, SiO ₂ —BaO series, SiO ₂ —Al ₂ O ₃ —BaO. , SiO ₂ —Al ₂ O ₃ —BaO—B ₂ O ₃ system, SiO ₂ —Al ₂ O ₃ —BaO—ZnO—B ₂ O ₃ system glass, Bi glass, and glass containing them as a main component Etc. are available.

  By the way, in this Embodiment, particle | grain coupling | bonding processing is performed on the metal foil 4. FIG. The behavior of the particles P during the particle binding process will be described with reference to FIG.

  FIG. 4 schematically shows the state in the vicinity of the metal foil 4 before (upper stage) and after (lower stage) of the particle bonding process. A large number of particles P exist on the metal foil 4. In this state, when the particle bonding process, that is, heating and holding at a predetermined temperature, the particles P react with each other, and the occupied volume decreases. This is so-called contraction. In normal firing, this shrinkage is isotropic. However, in the case of the present embodiment, the shrinkage in the direction parallel to the metal foil 4 (arrow X in the figure) is smaller than the shrinkage in the direction perpendicular to the metal foil 4 (arrow Z in the figure). This is because the particles P that are in contact with the metal foil 4 are bonded to the metal foil 4 on the surface by heating and holding at a predetermined temperature, and contraction in a direction parallel to the metal foil 4 is limited. . If the temperature for heating and holding is increased, shrinkage proceeds in a direction parallel to the metal foil 4, so that the particle structure 2 is cracked. In order to prevent this crack, as described above, the heating conditions in the particle bonding process are slight. Although it varies depending on the holding time of heating, as one criterion, assuming that the holding temperature for obtaining a dense sintered body is 1 (° C.) and the holding temperature in the particle bonding process is T 2 (° C.), T 2 = (0 .7 to 0.9) T1 is preferable. The holding temperature T2 in the more preferable particle bonding process is T2 = (0.75 to 0.85) T1.

  In addition, when an oxide is used as the particle P and the binder is removed in an oxidizing atmosphere, the oxide film OL formed by the binder removal process exists on the upper surface (surface) of the metal foil 4, and the lowermost layer The particles P are in contact with the metal foil 4 through the oxide film OL. Even in this case, similarly to the above, the contraction in the direction parallel to the metal foil 4 (arrow X in the figure) is limited during the particle bonding process.

In the present embodiment, as described above, the particle structure 2 is bonded to the surface of the metal foil 4 through the particle bonding process. Therefore, the flexibility of the particle structure 2 in the subsequent manufacturing process can be improved and its handling property can be ensured. In general, since cracks often occur during the firing process, it is difficult to produce a thin porous body by firing. However, in this embodiment, in order to form the particle structure 2 using the metal foil 4 as a support and to bond the particles P under conditions lighter than normal firing, the thickness is 100 μm or less, particularly 50 μm or less. The particle structure 2 can be manufactured. Since such a thin particle structure 2 can be manufactured, the thickness of the composite porous body 10 including the metal foil 4 can be 0.2 mm or less, and further 0.1 mm or less.

(Resin film lamination)
Next, “resin film bonding metal foil 7” is laminated on the particle structure 2. This resin film bonded metal foil 7 is obtained by bonding a resin film 71 to a metal foil 72. The metal foil 72 is finally used to form the conductive pattern 20, and is preferably made of the same material as the metal foil 4, and includes a copper foil, a nickel foil, an aluminum foil, a gold foil, and a plurality of these metal elements. Alloy foils and clad foils of these and other metals can be used. Moreover, the resin film 6 should just be comprised from resin which can be impregnated to the void | hole of the particle structure 2, for example, the thermosetting resin of a B stage state (semi-cured state), or heat which can be heated and melted A plastic resin is used. The resin film 6 may be a resin in which a small amount of thermoplastic resin is mixed with a thermosetting resin, and these resins are blended with various dispersants, plasticizers, flame retardants, additives and the like. There may be.

(Resin impregnation)
In a state where the resin film bonding metal foil 7 is laminated on the particle structure 2, the resin film bonding metal foil 7 is pressurized while being heated. By this treatment, the resin film 71 is melted and the melted resin is impregnated in the pores of the particle structure 2. This treatment can be performed by, for example, a heat press or a heat lamination. This treatment can be performed in the air, but is preferably performed in a vacuum in order to easily impregnate the particle structure 2 with a resin. As heating conditions, it is performed at a temperature at which the resin film 71 is cured or melted. As a temperature at which the resin film 71 is cured or melted, a condition of about 100 to 400 ° C. can be considered.

  The composite porous body 10 is completed through the above steps. The composite porous body 10 produced in this way can have a high magnetic permeability because the particles P are continuous and there is no resin having a low magnetic permeability between the continuous particles P.

  Thereafter, the conductive foil 20 is formed on the surface of the composite porous body 10 as shown in FIG. 2 by selectively removing the metal foil 72 formed on the surface of the prepared composite porous body 10 by a method such as etching. The formed composite electronic component 100 is completed.

As described above, according to the present embodiment, when the particles P of the composite porous body 10 are made of magnetic ferrite, the pores of the particle structure 2 are filled with resin, so that the dielectric constant is lowered. be able to. Further, it is possible to increase the dielectric constant by dispersing particles made of a high dielectric material in the resin, and the dielectric characteristics can be controlled by the design of the filling resin. The dielectric filler added to the filling resin may be any particle size that is not more than the shape of the pores, and is selected according to the desired dielectric properties. For example, when the dielectric constant is increased, TiO ₂ , BaTiO ₃ , BaxSr _1-x TiO ₃ , SrTiO ₃ , and CaTiO ₃ that have a high dielectric constant and a dielectric constant of 100 or more are used alone or as a main component. A composite oxide can be used. Further, the dielectric constant can be controlled by impregnating a carbon dispersion.

  The manufacturing method of the composite porous body 10 is not limited to the above embodiment, and various methods can be applied.

  For example, in the above embodiment, the particles P, the binder resin, and the resin powder are dissolved and dispersed in a solvent to prepare a paint, but the resin powder may not be added.

  Moreover, in the said embodiment, the resin impregnation process which laminates | stacks the resin film joining metal foil 7 with which the resin film 71 was joined to the metal foil 72 on the particle structure 2, and heats and pressurizes similarly to the above. By doing so, the composite porous body 10 in which the metal foil 4 as the first conductive metal substrate and the metal foil 72 as the second conductive metal substrate are respectively formed on the front and back surfaces of the particle structure 2 is produced. However, the present invention is not limited to this, and can be manufactured by other methods.

  For example, as shown in FIG. 5, two sheets prepared with the particle structure 2 are prepared on the metal foil 4 shown in FIG. 2 and arranged so that the particle structure 2 faces each other. The resin film 6 before being completely cured is placed in the B stage state or impregnated, and pressed while being heated. In this case, as shown in FIG. 5, a composite porous body 30 in which the particle structure 2 having a thickness of two layers is arranged can be produced.

  6 is a schematic external perspective view showing the configuration of the composite electronic component according to the second embodiment of the present invention, and FIG. 7 is a side cross-sectional view of the composite electronic component along the line BB in FIG. is there.

  As shown in FIGS. 6 and 7, the composite electronic component 200 of this embodiment is characterized in that the conductive pattern 20 is formed in a helical shape. Therefore, the composite porous body 10 has a multilayer structure, and the three-dimensional helical pattern is realized by connecting the end portions of the incomplete loop pattern formed in each layer by the via-hole electrode 21. The independent terminal electrode 20 a on the surface is connected to the end of the lowermost loop pattern via the via-hole electrode 21. Since the other points are the same as those of the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted. The conductive pattern 20 thus formed can also be used as an RFID antenna coil, for example.

  Next, the composite electronic component 200 configured as described above is obtained by laminating the particle structure 2 impregnated with resin on the surface of the composite porous body 10 produced by the manufacturing process shown in FIG. It can be produced by forming the conductive pattern 20 on the surface and repeating the lamination process of forming the via-hole electrode 21 as necessary several times. Here, the method of laminating the particle structure 2 impregnated with the resin is not limited. For example, the resin-cured particle structures 2 can be bonded and laminated with an adhesive. Moreover, it can also join using the impregnation resin of the particle structure 2 without using an adhesive agent. For example, when a thermoplastic resin is used, it can be joined by heating and cooling in a state where the resin-cured particle structures 2 are bonded together. Moreover, the particle structure 2 can be laminated | stacked in the state which resin has not hardened, and it can also affix using the adhesive force of impregnation resin. In this case, the particle structures 2 may be bonded together in a state where the particle structures 2 are bonded to the metal foil 4, and the metal foil 4 may be removed after bonding by impregnation resin curing. The laminated layers (composite porous body) may be a combination of materials having different material compositions and various characteristics, or the same material may be laminated.

  At this time, a normal printed circuit board processing process can be used as the processing process. For example, in the formation of the conductive pattern 20, methods such as a subtractive method, a semi-additive method, a vapor deposition method, sputtering, and ion plating can be used. In forming the via hole electrode 21, for example, laser processing, etching, or the like can be used. Therefore, it can be manufactured at a low cost and in a relatively short period of time.

  FIG. 8 is a schematic external perspective view showing the configuration of the composite electronic component according to the third embodiment of the present invention.

  As shown in FIG. 8, the composite electronic component 300 is characterized in that an electronic component such as a semiconductor IC chip 22 and a passive element 23 such as a capacitor is mounted on the surface of the composite porous body 10. Since the other points are the same as those of the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted. The composite electronic component 300 configured as described above can function as an RFID antenna module, for example.

  9 to 11 are schematic cross-sectional views showing how chip components are mounted on the composite porous body 10.

  In the embodiment of FIG. 9A, the semiconductor IC chip 22 and the passive element 23 are mounted on the surface of the composite porous body 10. The composite porous body 10 has a multilayer structure, and the semiconductor IC chip 22 and the passive element 23 are formed in a spiral conductive pattern 20 formed on the surface of the composite porous body 10 via an inner layer (or surface layer) wiring layer 25. And electrically connected.

  In the embodiment of FIG. 9B, the semiconductor IC chip 22 and the passive element 23 are mounted on the back surface of the composite porous body 10. Therefore, the metal foil 4 at the center of the back surface of the composite porous body is selectively removed by a technique such as etching, and the semiconductor IC chip 22 and the passive element 23 are mounted in the region where the porous body 1 is exposed. The composite porous body 10 has a multilayer structure, and the semiconductor IC chip 22 and the passive element 23 are formed in a spiral conductive pattern 20 formed on the surface of the composite porous body 10 via an inner layer (or surface layer) wiring layer 25. And electrically connected.

  In the embodiment of FIG. 10A, a cavity 10C is formed in advance at the center of the surface of the composite porous body 10, and the semiconductor IC chip 22 and the passive element 23 are mounted in the cavity 10C. The cavity can be formed by etching the porous body, for example. The cavity 10C in which the semiconductor IC chip 22 and the passive element 23 are mounted is filled with a resin 24, and these electronic components are built in the substrate. As the resin 24 at this time, it is preferable to use the same material as the impregnating resin of the particle structure 2, but other resins can also be used. The semiconductor IC chip 22 and the passive element 23 are electrically connected to the spiral conductive pattern 20 formed on the surface of the composite porous body 10 via the inner wiring layer 25.

  In the embodiment of FIG. 10B, a cavity 10C is formed in advance in the center of the back surface of the composite porous body 10, and the semiconductor IC chip 22 and the passive element 23 are mounted in the cavity 10C. Therefore, the metal foil 4 at the center of the back surface of the composite porous body can be selectively removed by a technique such as etching, and can be formed by etching the region where the porous body 1 is exposed. The cavity 10C in which the semiconductor IC chip 22 and the passive element 23 are mounted is filled with a resin 24, and these electronic components are built in the substrate. As the resin 24 at this time, it is preferable to use the same material as the impregnating resin of the particle structure 2, but other resins can also be used. The semiconductor IC chip 22 and the passive element 23 are electrically connected to the spiral conductive pattern 20 formed on the surface of the composite porous body 10 via the inner wiring layer 25.

  In the embodiment of FIG. 11A, the semiconductor IC chip 22 is embedded in the composite porous body 10 in advance, and the passive element 23 is mounted on the surface of the composite porous body 10. Therefore, the composite porous body 10 has a multilayer structure, and the semiconductor IC chip 22 and the passive element 23 are spirally formed on the surface of the composite porous body 10 via the wiring layer 25 of the inner layer (or the surface layer). The conductive pattern 20 is electrically connected.

  In the embodiment of FIG. 11B, the semiconductor IC chip 22 is embedded in the composite porous body 10 in advance, and the passive element 23 is mounted on the back surface of the composite porous body 10. Therefore, the metal foil 4 at the center of the back surface of the composite porous body is selectively removed by a technique such as etching, and the passive element 23 is mounted in the region where the porous body 1 is exposed. The composite porous body 10 has a multilayer structure, and the semiconductor IC chip 22 and the passive element 23 are formed in a spiral shape formed on the surface of the composite porous body 10 via the inner (or surface) wiring layer 25. It is electrically connected to the conductive pattern.

  In addition, the composite electronic component shown to Fig.11 (a) can be manufactured by the process shown, for example in FIG. In this step, first, a semiconductor IC chip 22 is mounted face-up on the surface of the composite porous body 10, and a resin sheet 8 such as a prepreg is laminated thereon (FIG. 12A). Next, the via hole electrode 26 is formed on the resin sheet 8, the conductive pattern 20 is formed on the surface of the resin sheet 8, and a new composite porous body made of the particle structure 2 impregnated with the resin is laminated thereon. (FIG. 12B). Thus, the semiconductor IC chip 22 is embedded in the composite porous body 10, and the wiring layer 25 is formed in the inner layer of the composite porous body having a multilayer structure. Thereafter, the via-hole electrode 26 is formed in the composite porous body 10, the spiral conductive pattern 20 is formed on the surface of the composite porous body 10, and the passive element 23 is further mounted thereon, whereby FIG. The composite electronic component shown in FIG. 12 is completed (FIG. 12C).

  The composite electronic component shown in FIG. 11B can also be manufactured by a process similar to the process shown in FIG. At that time, the semiconductor IC 22 is embedded in the composite porous body 10 in a face-up state, and passes through the wiring layer 25 formed on the inner layer of the composite porous body having a multilayer structure. It is electrically connected to the element 23.

  As described above, various forms of mounting the chip component on the composite porous body 10 are conceivable. In any case, since the magnetic permeability of the substrate is very high, the influence of noise can be sufficiently suppressed. it can. In addition, since a desired conductive pattern is formed on a very thin and flexible substrate and various chip components are mounted, it is possible to contribute to a reduction in size and thickness of an electronic device on which the composite electronic component is mounted. Moreover, in the manufacture, the same processing method as a general printed circuit board can be used, and it can be manufactured at a low cost and in a relatively short time. In addition, since it is easy to handle and highly flexible, it can be placed in close contact with the casing surface of a non-planar electronic device, and the degree of design freedom can be increased.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention, and these are also included in the present invention. Needless to say.

  For example, in the above-described embodiment, an antenna device such as an RFID antenna coil or an RFID antenna module is given as an example of a composite electronic component. However, the present invention is not limited to this and is applicable to all electronic components. can do.

FIG. 1 is a schematic external perspective view showing the configuration of the composite electronic component according to the first embodiment of the present invention. FIG. 2 is a side sectional view of the composite electronic component taken along the line AA in FIG. FIG. 3 is a diagram illustrating a manufacturing process of the composite porous body 10. FIG. 4 schematically shows the state in the vicinity of the metal foil 4 before (upper stage) and after (lower stage) of the particle bonding process. FIG. 5 is a diagram illustrating a manufacturing process of the composite porous body 30. FIG. 6 is a schematic external perspective view showing the configuration of the composite electronic component according to the second embodiment of the present invention. FIG. 7 is a side cross-sectional view of the composite electronic component taken along line B-B in FIG. 6. FIG. 8 is a schematic external perspective view showing the configuration of the composite electronic component according to the third embodiment of the present invention. FIG. 9 is a schematic cross-sectional view showing a chip component mounted on the composite porous body 10, wherein (a) shows a front surface mount type and (b) shows a back surface mount type. FIG. 10 is a schematic cross-sectional view showing a chip component mounted on the composite porous body 10, wherein (a) shows a front cavity mounting type and (b) shows a back cavity mounting type. FIGS. 11A and 11B are schematic cross-sectional views showing a chip component mounting form on the composite porous body 10, wherein FIG. 11A shows an IC embedded surface mounting type, and FIG. 11B shows an IC embedded back surface mounting type. FIG. 12 is a diagram showing a manufacturing process of the IC-embedded surface mount type composite electronic component shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Porous body 2 Particle structure 3 Resin phase 4 Metal foil 5 Coating film 6 Resin film 7 Resin film joining metal foil 8 Resin sheet 10 Composite porous body 10C Cavity 20 Conductive pattern 20a Terminal electrode 21 Via hole electrode 22 Semiconductor IC chip 23 Passive Element 24 Resin 25 Wiring layer 26 Via-hole electrode 30 Composite porous body 71 Resin film 72 Metal foil 100 Composite electronic component 200 Composite electronic component 300 Composite electronic component OL Oxide film P Particle

Claims (12)

A composite porous body, and at least a conductive pattern formed on the surface of the composite porous body,
The composite porous body includes a particle structure in which particles made of a magnetic material are bonded by a neck and have pores communicating with the outside, and a resin phase filled in the pores of the particle structure. Composite electronic parts.   The composite electronic component according to claim 1, wherein the particle structure has a network-like structure in which the particles are continuous.   The composite electronic component according to claim 1, wherein the particle structure has a porosity of 20 to 80%.   4. The composite electronic component according to claim 1, wherein the conductive pattern is formed in a spiral shape.   The composite electronic component according to any one of claims 1 to 3, wherein the conductive pattern is formed in a helical shape.   The passive element electrically connected with the said conductive pattern is further provided, The said passive element is mounted in the surface or the back surface of the said composite porous body, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. The composite electronic component described.   The composite electronic component according to claim 1, further comprising a semiconductor IC chip electrically connected to the conductive pattern.   The composite electronic component according to claim 7, wherein the semiconductor IC chip is mounted on a front surface or a back surface of the composite porous body.   8. The composite electronic component according to claim 7, wherein the semiconductor IC chip is mounted in a cavity formed in the composite porous body.   The composite electronic component according to claim 7, wherein the semiconductor IC chip is embedded in the composite porous body. Applying a paint obtained by dissolving and dispersing at least magnetic particles and a binder in a solvent to a metal foil;
Performing a binder removal treatment of the paint applied to the metal foil;
Producing a particle structure by performing a binding treatment of the magnetic particles;
Laminating a resin on the particle structure;
Impregnating and curing the resin to the particle structure by pressurizing the resin while heating;
And a step of forming a conductive pattern on the surface of the particle structure impregnated with the resin. 12. The method of manufacturing a composite electronic component according to claim 11, wherein the step of forming the conductive pattern includes a step of selectively removing the conductive film formed on the surface of the particle structure.

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