JP2009033152A - Ceramic structure, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing efficiently a ceramic structure which is equipped with a conductor of linear configuration inside, preventing or avoiding disadvantage caused by the shrinkage of ceramics in sintering. <P>SOLUTION: The ceramic structure includes a ceramic material 24 which forms a ceramic matrix of the ceramic structure by sintering, and a conductor material 26 containing a conductor constituent, which is equipped with a hollow portion 30a capable of absorbing shrinkage stress applied to the relevant conductor material 26 in the inside thereof, wherein a conductive material containing ceramic formed body 22 containing the conductor material 26 in the ceramic material 24 in the linear configuration is prepared and this ceramic formed body 22 is sintered. By the deformation or the shrinkage of the hollow portion 30a, the conductor material 26 absorbs the shrinkage stress generated in sintering, making it possible to suppress the generation of tensile stress in the ceramics matrix. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a ceramic structure having a lead wire inside and a method for manufacturing the same.

Examples of the ceramic structure having a conductive wire inside include electronic components such as a ceramic inductor and a noise filter. Various manufacturing methods are known for such a ceramic structure. For example, a method is known in which a conductor layer is formed by printing each time a ceramic green sheet is laminated, and is made conductive through via holes formed in the sheet (Patent Documents 1 and 2). In addition, it is also described that a ceramic slurry cast so as to enclose a continuous conductive wire is molded by a gel cast method, and then cured and sintered (Patent Documents 3 and 4).
JP-A-6-163269 JP-A-6-275438 JP-A-11-126724 Japanese Patent Laid-Open No. 11-345731

  The method of obtaining a molded body containing continuous conductive wires and integrating them by sintering can avoid the complexity of the manufacturing process and can be efficiently manufactured as compared with the technique using lamination or printing. Promising in terms. In addition, since a metal coil wire can be used, it is useful as a manufacturing method of a large current inductor or a noise filter used for an electronic device or the like. Furthermore, the gel casting method has a merit in miniaturization because a highly accurate shape can be imparted.

  However, due to the difference in shrinkage between the ceramics and the lead wire during sintering, tensile stress, etc. is applied to the ceramics and the sintered body breaks, or the residual stress causes delayed fracture and mechanical strength decreases over time. there were. This was particularly noticeable in the case of enclosing conductive wires having a spiral form. In addition, there is a possibility that electrical characteristics are deteriorated by applying tensile stress to ceramics. Therefore, at present, it is not realistic to obtain this type of ceramic structure by a gel cast method or the like.

  Accordingly, an object of the present invention is to provide a method for efficiently producing a ceramic structure having a lead wire inside while suppressing or avoiding inconvenience due to ceramic shrinkage during sintering. Another object of the present invention is to provide a ceramic structure that includes a lead wire such as a coil therein, and that suppresses or avoids the influence of stress during sintering on the ceramic.

  The present inventors effectively absorb the shrinkage stress generated during the sintering of the ceramic by encapsulating the conductor material in a linear form by the stress absorbing ability provided inside the conductor material, thereby effectively reducing the tensile stress and the like in the ceramic. It has been found that a sintered body in which cracking is suppressed can be obtained by suppressing or avoiding generation. Based on these findings, the following means are provided.

  According to the present invention, there is provided a method for manufacturing a ceramic structure including a linear conductor inside, wherein the ceramic material is formed by sintering a ceramic matrix of the ceramic structure, and the conductive material includes a conductor component. A conductive material-encapsulating ceramic molded body including a conductive material having a stress-absorbing ability capable of absorbing shrinkage stress applied to the conductive material on the inner side, and encapsulating the conductive material in a linear form in the ceramic material. There is provided a manufacturing method including a formed body preparation step to be prepared and a firing step for sintering the conductor material-containing ceramic formed body.

  In this manufacturing method, the said compact body preparation process can be made into the process of preparing the said conductor material inclusion ceramic molded body included in the state which made the surface of the said conductor material closely_contact | adhere to the said ceramic material. Moreover, the shrinkage stress generated in the vicinity of the surface of the conductor material in the ceramic firing step can be relaxed.

  The conductor material may have a hollow portion that can be deformed or reduced by the shrinkage stress, and the hollow portion has a through-hole portion that penetrates the conductor material in a longitudinal direction and / or the conductor material. A plurality of pores dispersed in the substrate. Furthermore, the conductive material may include a volume reducing component that can be reduced by burning or sublimation in the baking step. Further, the linear form may include a spiral form.

  In this production method, the compact preparation step includes ceramic powder, an organic dispersion medium having a reactive functional group, and a gelling agent, which is solidified by a reaction between the organic dispersion medium and the gelling agent. It can be set as the process of producing the said ceramic molded object using.

  In this manufacturing method, the said conductor material can be made into the linear member which has the said linear form, It is preferable that this linear member is equipped with flexibility. In this aspect, the formed body preparation step is a step of supplying the ceramic material slurry to a forming cavity in which the linear form of the conductor material is arranged to produce the linear conductor material-containing ceramic formed body. be able to.

  The forming body preparing step may include a step of disposing the linear member in the forming cavity in a state where the linear member is wound around an unfired or already fired ceramic formed body having a predetermined outer shape. The ceramic molded body may include a guide for winding the linear member.

  In the present manufacturing method, the molded body preparation step is performed by preparing a linear cavity-containing ceramic molded body including the ceramic material and a linear cavity corresponding to the linear form in the ceramic material. It can also be set as the process of preparing the said conductor material inclusion ceramic molding by filling the fluid said conductor material in a cavity.

  In the forming body preparing step, two or more cavity forming ceramic bodies that form the linear cavity by integration are used, and the cavity forming ceramic bodies are joined and integrated to form the linear cavity. It is good also as a process including filling the said conductor material in. The two or more cavity-forming ceramic bodies include one or more first cavity-forming ceramic bodies having concave portions corresponding to the linear cavities on the surface, and opening portions of the concave portions. It is good also as what consists of a 1 or 2 or more 2nd cavity formation ceramic molded object which has the wall surface which shields. Furthermore, the two or more cavity-forming ceramic bodies may each have an outer shape that forms the outer shape of the conductive material-containing ceramic molded body by the integration.

  In this manufacturing method, the molded body preparing step includes the ceramic material and the non-linear conductor material-containing ceramics including the ceramic material and the non-linear form of the conductor material having a shape that can be processed into the linear form in the ceramic material. A formed body is prepared, and after removing a part of the non-linear conductor material to obtain the linear form, a slurry of the ceramic material is supplied to the removed portion of the conductor material, and the slurry is solidified. Thereby, it can be set as the process of preparing the said linear conductor material inclusion ceramic molded object. In this aspect, the non-linear conductor material-containing ceramic molded body is prepared, and the non-linear cavity-containing ceramic molded body having a cavity corresponding to the non-linear shape in the ceramic material is prepared. It can be produced by filling the fluid conductive material. In these aspects, the linear form may have a spiral form, and the non-linear form may be a columnar or tubular form having a spiral convex part on the outer periphery.

  In the manufacturing method of the present invention described above, the conductor material can contain one or more conductor components selected from the group consisting of Ag, Au, Pt, Cu, Ni, Pd, and Rh. Moreover, in these manufacturing methods, it is preferable that the shrinkage | contraction rate in the said baking process of the said ceramic molded object is 15% or more and 45% or less. Moreover, it is preferable that these manufacturing methods are the manufacturing methods of an electronic component.

  According to the present invention, there is provided a ceramic structure obtained by any of the above production methods.

  According to the present invention, there is provided a ceramic structure, which is a sintered ceramic matrix, and a linear conductor included in the sintered ceramic matrix. A structure is provided. In this aspect, the hollow portion or the trace thereof includes a portion in which the hollow portion existing in the conductor material before sintering is deformed, reduced or closed by the sintering.

  According to the present invention, an unsintered ceramic formed body is a non-sintered ceramic matrix and a conductor material containing a conductor component, and a stress absorption capable of absorbing the shrinkage stress related to the conductor material on the inside thereof. A conductive material having a function, and including the conductive material in a linear form in the ceramic material. The conductor material may include any one selected from a hollow portion that can be deformed or reduced and a volume-reducing component that can be reduced by burning or sublimation as the ceramic material is fired.

  In the method for producing a ceramic structure of the present invention, a ceramic material and a conductor material containing a conductor component, the conductor material having a stress absorbing ability capable of absorbing the shrinkage stress related to the conductor material inside the ceramic material, It is possible to prepare a conductive material-containing ceramic molded body that includes the conductive material in a linear form in the material and sinter this ceramic molded body.

  According to the manufacturing method of the present invention, when a shrinkage stress is generated as the ceramic material is sintered, the conductive material contained in the ceramic material itself has a stress absorbing ability provided on the inner side of the conductive material. The acting shrinkage stress can be absorbed. For this reason, the tensile stress etc. which arise in a ceramic matrix resulting from inclusion of the conductor material from which shrinkage | contraction rate differs can be suppressed effectively, and generation | occurrence | production of a crack etc. can be suppressed. Further, since the stress absorbing ability is provided inside the conductor material, the formation of voids near the interface between the conductor material and the ceramic matrix is suppressed due to the exertion of the stress absorbing ability. For this reason, it is possible to ensure a good adhesion state between the surface of the conductor material and the ceramic matrix and to ensure good electrical characteristics.

  In addition, according to the present manufacturing method, when a linear conductor material is encased in direct contact with the ceramic material, the conductor material continuously absorbs the shrinkage stress generated with the progress of sintering. In accordance with the shrinkage of the (ceramic matrix), the conductor material is also deformed and the ceramic material can be sintered while maintaining the contact state between the conductor material and the ceramic material. That is, it is possible to suppress a rapid and high shrinkage stress from acting on the conductor material, and it is possible to effectively suppress the tensile stress generated in the vicinity of the interface of the conductor material. On the other hand, when the burnt resin layer is provided on the outer surface of the conductor material, a gap is formed between the conductor material and the ceramic material after the resin layer disappears. When contacted with the conductor surface, a rapid and high shrinkage stress acts, resulting in a large tensile stress that is likely to cause cracks in the matrix. In the present specification, “shrinkage stress” means a shrinkage stress generated when a ceramic material is sintered to form a ceramic matrix.

  Further, the ceramic structure of the present invention is a sintered ceramic matrix, and a conductor having a linear shape enclosed in the sintered ceramic matrix, and a conductor having a hollow portion or a trace thereof inside thereof. Can be provided. In this structure, the hollow part or the trace provided in the linear conductor functions as a hollow part capable of absorbing shrinkage stress during sintering. For this reason, the ceramic structure including the conductor having the hollow portion or its trace is a ceramic structure excellent in mechanical strength because the generation of tensile stress is suppressed in the ceramic matrix. In addition, since the hollow portion or its trace is provided inside the conductor, the tensile stress generated in the ceramic matrix is surely suppressed, and the good contact state between the conductor surface and the ceramic matrix is also maintained.

  Hereinafter, a ceramic structure manufacturing method, a ceramic structure, an unsintered ceramic molded body, and the like according to embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 shows an example of the steps of the method for manufacturing a ceramic structure of the present invention, FIG. 2 shows an example of the ceramic structure, and FIG. 3 shows an example of a linear conductor material-containing ceramic molded body. 4 to 7 show various examples of the linear conductor material used for manufacturing the ceramic structure of the present invention.

(Manufacturing method of ceramic structure)
As shown in FIG. 1, the manufacturing method of the present invention includes a step of preparing a linear conductor material-containing ceramic molded body (hereinafter simply referred to as a ceramic molded body) 22 including a linear conductor material, and the ceramic molding. And a step of sintering the body 22. A ceramic structure 2 to be obtained by this manufacturing method includes a ceramic matrix 4 and a linear conductor 6 included therein.

(Molded body preparation process)
In this step, a ceramic molded body 22 that is a precursor of the ceramic structure 2 that is a sintered body is prepared using the following materials. A ceramic molded body 22 corresponding to the ceramic structure 2 of FIG. 2 is shown in FIG. The ceramic molded body 22 includes an unfired ceramic material 24 and a linear conductor material 26. In the form shown in FIG. 2, the conductor material 26 is a cylindrical body having a through-hole portion 30a.

(Ceramic materials)
The ceramic material 24 constituting the ceramic matrix 4 by sintering is not particularly limited, and various known ceramic powders or mixed powders of ceramic powder and glass powder and other materials can be used. In the ceramic structure 2 of the present invention, a conductor 6 is provided, and considering application to an electronic component such as an inductor or a noise filter, the ceramic matrix 4 is preferably an insulating ceramic. The insulating ceramic is not particularly limited, and known ones can be used. For example, in addition to magnetic materials such as Ni—Cu—Zn-based ferrite and Ni—Zn-based ferrite, alumina-based ceramics, zirconia-based ceramics, magnesia-based ceramics, silicon nitride-based ceramics, barium titanate-based ceramics, and the like can be given. Therefore, as the ceramic material 24, ceramic powder produced by sintering such insulating ceramics can be used.

(Conductor material)
The conductor material 26 is a material constituting the conductor 6 in the ceramic structure 2. The conductor material 26 contains a conductor component. The conductor component can be composed of a single metal selected from Ag, Pt, Au, Pd, Cu, Ni, Rh, or the like, or an alloy containing any of these as a main component.

  The conductor material 26 may be any material as long as it can form a conductor component matrix 28 that forms a continuous conduction path inside the ceramic structure 2 so that a predetermined conduction state can be formed.

  One preferable form of the conductive material 26 is the conductive material 26 having a linear shape in advance. Such a conductor material 26 is a conductor that continuously contacts after firing in an appropriate insulating matrix such as resin, glass, ceramics, etc. in addition to a linear body such as a metal wire having a metal phase as a continuous phase as a conductor component matrix 28. Examples include a linear body including a conductor component matrix 28 including conductor particles 29 capable of forming a passage. The conductor material 26 in a linear form may further include a metal wire in the conductor component matrix 28 that can form a conduction path by the conductor particles 29.

  The conductor material 26 having such a linear form may be a single filament, a bundle of filaments, a filament, or the like.

  Another preferred form of the conductive material 26 is a form of a flowable conductive material containing the conductive particles 29 in a suitable medium, such as a conductive paste. By forming or processing such a conductor material 26 into a linear form, the linear form of the conductor material 26 having the conductor component matrix 28 can be obtained. The conductor paste usually contains conductor particles 29 and a fluid dispersion medium for dispersing and holding the conductor particles 29. The conductor particles 29 can take various forms such as a spherical shape and a flake shape. Generally, a polymer material or a solvent is used as the dispersion medium. In the conductor paste, the conductor medium 29 can be formed by eliminating the dispersion medium and densifying the conductor particles 29 close to each other. Such a polymer material and a solvent correspond to the volume reducing component 32 described later.

  By including the linear conductive material 26 in the ceramic material 24 with the fluid conductive material 26, the shrinkage stress accompanying the sintering of the ceramic material 24 can be absorbed more effectively. That is, the conductor paste includes a volume reducing component and a conductor component, and as a result of the volume reducing component disappearing prior to sintering, a hollow portion (void) is generated between the conductor components, and thus the generated hollow portion is included. The conductor components move in the linear cavities and can be close to each other and densified with sintering. For this reason, the shrinkage stress can be absorbed more effectively than the conductor material 26 having a line shape in advance.

  The outer shape of the cross section orthogonal to the axial direction of the conductor material 26 having such a linear shape is not particularly limited. In addition to a circular shape, a square shape, or the like, an indefinite shape or a flat shape may be used. Moreover, the cross-sectional shape of the cross section orthogonal to the axial direction of the conductor material 26 in the linear form is not particularly limited, but FIG. 3, FIG. 4 (a) to (d), FIG. 5 (c), FIG. ) May have a hollow portion 30a, as shown in FIGS. 5 (a), 5 (b), 6 (a) and 7, and may be solid. It may be a body. Moreover, as shown in FIG.4 (e), you may have a some hollow part 30a. Furthermore, although not shown, a channel-like body may be used.

(Stress absorption capacity)
The conductive material 26 can have a stress absorption capability on the inside thereof. In this specification, the stress absorbing ability means an ability to absorb at least a part of the stress when a shrinkage stress is generated in the ceramic material 24 including the conductor material 26. The specific form of the stress absorption ability is not particularly limited. The “inside of the conductor material” means a position separated from the outside of the conductor material 26 (ceramic material 24 side) by the conductor component matrix 28 constituting the conductor material 26, and from the surface of the conductor material 26. It includes both the inside of the inner conductor component matrix 28 and the outer side of the conductor component matrix 28 that is partitioned by the thickness of the conductor component matrix 28.

(Hollow part)
One form in which the conductive material 26 can exhibit the ability to absorb stress is a form having a hollow portion 30 that can be deformed or reduced by shrinkage stress inside the conductive material 26. By imparting the stress absorption capability by the hollow portion 30, when the conductor material 26 is subjected to shrinkage stress from the ceramic material 24 side, the stress concentrates on the hollow portion 30 or the vicinity thereof and the hollow portion 30 is deformed or reduced. By doing so, the contraction stress is absorbed. As a result, generation of tensile stress or the like in the ceramic matrix 4 can be suppressed or avoided.

  The hollow part 30 can take the form of the through-hole part 30a of the various forms shown to Fig.4 (a)-(e), for example. Various conductor materials 26 shown in FIGS. 4A to 4E are provided with through-holes 32 a penetrating in the axial direction as hollow portions 30. By providing the through-hole portion 30 a as the hollow portion 30, a large stress absorbing ability can be exhibited in the entire conductor material 26. When the hollow portion 30 is used as the through hole portion 30a, in order to facilitate the deformation and reduction of the through hole portion 30a, the thickness of the conductor material 26 surrounding the through hole portion 30a is set as shown in FIG. You may form the weak part 34 which stress concentrates on the conductor material 26 by changing partially. The shape and arrangement of the fragile portion 34 are not particularly limited. By providing the fragile portions 34 at regular intervals in the axial direction, the linear conductive material 26 is easily deformed or reduced in the axial direction.

  Further, as shown in FIGS. 4B and 4C, the conductive material 26 may be a concavo-convex cylindrical body that is easily subjected to shrinkage stress. If the conductor material 26 has such an uneven shape, the through hole 30a is easily deformed and reduced by the compressive stress acting on the ceramic material 24. The uneven shape is not particularly limited, and can be formed at regular intervals in the axial direction or the circumferential direction.

  Furthermore, as shown in FIG. 4D, the conductor material 26 may be a cylindrical body obtained by curling a flat strip that is flat and elongated in the axial direction into a cylindrical shape. In this case, it is preferable that the long end portion that is curled and opposed or overlapped is closed so as to suppress the inflow of ceramic slurry or the like into the through-hole portion 30a formed by curling. Preferably, the curled long ends are overlaid. Moreover, it is preferable that the diameter of the curled conductor material 26 can be changed so that the shrinkage stress can be absorbed. For example, in order to change the diameter of the curled conductor material 26, the end portions that are curled and faced or overlapped may be formed to be relatively movable in the circumferential direction without welding or the like.

  Furthermore, as shown in FIG. 4E, the conductor material 26 may include two or more through-hole portions 30a.

  The hollow portion 30 can also be in the form of a number of holes 30b dispersed in the conductor component matrix 28. For example, as shown in FIG. 5A, the conductor material 26 may be porous. When the hollow portion 30 is a large number of holes 30b dispersed in the conductor component matrix 28, the porosity and the hole diameter distribution in the conductor matrix 28 are not particularly limited. By having a large number of hole portions 30b as the hollow portions 30, uniform deformation or reduction of the entire conductor material 26 is facilitated.

  The hole 30b may be formed in a surface layer that can contact the ceramic material 24 in the conductor material 26. However, the hole diameter of the hole 30b that opens on the surface of the conductor material 26 is a slurry containing ceramic powder in the compact preparation step, etc. It is preferable that it is a grade which does not penetrate easily. The surface of the conductor material 26 is preferably smooth. For this purpose, as shown in FIG. 5 (b), the surface of the porous conductor portion 28 may be provided with a dense conductor material layer 29 in the form of an outer skin, and the conductor component matrix 28 may have an outer peripheral side. An inclined structure with a reduced porosity may be provided. Similar to the case where the through holes 32a and the like are provided, even when the dispersed holes 30b are provided, the conductor material 26 can be easily subjected to contraction stress by including the fragile portions 34 and the concavo-convex portions. .

  Further, as shown in FIG. 5C, the conductor material 26 may include a through hole portion 30 a and a plurality of hole portions 30 b dispersed in the conductor component matrix 28.

  As the conductor material 26 having the dispersed holes 30b, a conductor component matrix in which a porous metal linear body or a capsule 30 having a hollow portion corresponding to the hole 30b or the hole 30b is dispersed in an insulating matrix The linear body which has 28 is mentioned. The linear conductor material 26 including the conductor component matrix 28 having a porous insulating matrix can also be formed by filling a linear cavity with a conductor paste containing the capsule-like body. The capsule-like body is preferably formed of a component having a lower mechanical strength than the volume reducing component or conductor component matrix 28 described later.

(Volume reduction component)
Another form for imparting stress absorption capability to the conductor material 26 is a form having a volume reducing component 32 inside the conductor material 26 in the firing step. The volume-reducing component may be a component whose volume is reduced (the volume is reduced) by burning or sublimation at least partly in the firing step. When the conductor material 26 has the volume reducing component 32, the volume occupied by the volume reducing component 32 inside the conductor material 26 is reduced, so that the contraction stress can be absorbed according to the reduction degree. . As the volume reducing component 32, various resins, oil-based paints, organic materials such as wax, low melting point metals and the like can be used.

  As a form which arranges the volume reducing component 32 inside the conductor material 26, as shown to Fig.6 (a)-(b), the part enclosed by the said cylindrical body of the cylindrical body formed with the conductor material 26 And a columnar or cylindrical volume reducing component 32. In this case, as described above, the conductor material 26 may be the conductor material 26 having a linear shape as described above, or the linear material is filled by filling the linear cavity with a fluid conductive material 26 such as a conductor paste. It may have a form. In addition, when providing the volume reducing component 32 as a cylindrical body, as already mentioned, the effect equivalent to providing the through-hole part 30a can be acquired.

  As another form, as shown in FIG. 7A, a form having a conductor component matrix 28 in which conductor particles 29 are dispersed in the continuous phase of the volume reducing component 32 can be mentioned. Alternatively, as shown in FIG. 7B, a conductor component matrix 28 in which particulate volume reducing components 32 are dispersed in a continuous phase of conductor components may be used. When the volume reducing component 32 is dispersed in the form of particles, the volume reducing component 32 may be solid particles or capsule (hollow) particles. When the volume-reducing component 32 is a capsule-like particle, the volume-reducing component 32 disappears, thereby forming a hollow portion larger than the volume-reducing component amount, thereby effectively exhibiting the ability to absorb stress.

  The conductive material 26 including such a volume reducing component 32 includes a conductive particle 29 and a fluid conductive material 26 such as a conductive paste containing a polymer material or a solvent for dispersing the conductive particles 29 as the volume reducing component 32. It can be obtained by filling and solidifying.

  The conductor material 26 is provided with stress absorbing ability in various forms, and may be provided with stress absorbing ability in one of the various forms described above, or the hollow portion 30 and volume reducing component in various forms. The stress absorbing ability may be provided in a form in which two or more types selected from the above are combined.

  The conductor material 26 in a linear form may be provided with a volume-reducing component layer outside the conductor component matrix 28, that is, as a skin of the conductor component matrix 28. By providing such a skin, it is possible to delay the contraction stress acting on the conductor material 26. In this case, the ceramic material 24 that shrinks with sintering comes into contact with the surface of the conductor material 26. However, since the conductor material 26 has a stress absorbing capability inside thereof, it is resistant to such a sudden and strong shrinkage stress. Correspondingly, generation of cracks and the like can be effectively suppressed.

  The conductor material 26 having a linear form in advance is preferably flexible. The linear form of the conductive material 26 itself is bent, so that the shrinkage stress accompanying the sintering is effectively absorbed by the linear form of the conductive material 26. In order to give flexibility to the conductor material 26 such as a metal wire having a linear shape in advance, it can depend on the material of the conductor material 26, and the linear conductor material 26 can be bundled or stranded. The body is preferred. If it is a bundle-like body or a corrugated body, it can be formed more easily than a single metal wire having the same cross-sectional area. Moreover, when giving flexibility, you may form a weak part with thin thickness in the site | part which is giving a fixed space | interval or flexibility in the conductor material 26. FIG.

  The form of the conductor material 26 is not particularly limited. The linear form with which the conductor material 26 is provided may be linear, for example, it has a two-dimensional form having one or more bent portions or curved portions, such as a Z shape, a zigzag shape, and a wavy shape. Also good. Further, it may have a three-dimensional form such as a spiral structure that turns with a bent part or a curved part such as a coil shape. Moreover, the said form may combine these various forms 2 or more types. As shown in FIG. 4, a two-dimensional configuration having a plurality of bent portions and the like and a spiral structure can be provided, and linear portions can be provided at both ends. In the ceramic structure 2 of the present invention obtained by this manufacturing method, the conductor 6 itself can absorb the shrinkage stress and the like generated in the ceramic matrix 4, so that the tertiary structure such as a complicated two-dimensional form or a circular structure is obtained. Even if the original form is provided, cracks and cracks in the vicinity of the interface of the conductor 6 can be effectively suppressed.

  In the ceramic molded body 22 including the conductive material 26, a part of the conductive material 26 may extend to the outside of the ceramic molded body 22, or the whole may remain inside.

  The ceramic molded body 22 is not particularly limited and can be prepared by various known ceramic molding methods such as a powder compression molding method. According to the present invention, it is possible to suppress or avoid the occurrence of tensile stress or the like in the ceramic matrix in the firing process regardless of the forming method. The ceramic molded body 22 of the present invention is preferably formed by an in-situ solidification method such as a gel casting method among various molding methods. An in-situ solidification method such as a gel cast method is suitable for efficiently producing a minute part with high accuracy. Hereinafter, the process of manufacturing the precursor molded body 22 of the ceramic structure 2 by the gel cast method will be described.

  In the gel casting method, a ceramic slurry containing ceramic powder is used. The ceramic slurry used for the gel casting method contains a gelling agent (organic polymerizable component) and an organic dispersion medium in addition to the ceramic powder. The type of the gelling agent and the organic dispersion medium is not particularly limited, but the organic dispersion medium preferably has a reactive functional group that reacts with the gelling agent and solidifies.

  The dispersion medium that can react with the gelling agent preferably has a functional group such as a hydroxyl group, a carboxyl group, and an amino group. The reactive functional group possessed by the dispersion medium can be 1 or 2 or more and can be the same or different. Examples thereof include diols such as ethylene glycol, polyhydric alcohols such as triols such as glycerin, and polybasic acids such as dicarboxylic acid. Preferably, polybasic acid esters such as dimethyl glutarate and polyhydric alcohol esters such as triacetin can be preferably used. More preferred are esters having 20 or less carbon atoms.

  Specific examples of such dispersion media include ester-based nonions, alcohol ethylene oxides, amine condensates, nonionic special amide compounds, modified polyester compounds, carboxyl group-containing polymers, maleic polyanions, polycarboxylic acid esters, polysaccharide types. Examples thereof include polymer nonionic, phosphate ester, sorbitan fatty acid ester, sodium alkylbenzene sulfonate, and maleic acid compound.

  The gelling agent can be appropriately selected in consideration of the reactivity with the dispersion medium, but when an ester size solvent is used, it preferably has an isocyanate group or an isothiocyanate group. Examples of such gelling agents include MDI (4,4-diphenylmethane diisocyanate) isocyanate (resin), HDI (hexamethylene diisocyanate) isocyanate (resin), and TDI (tolylene diisocyanate) isocyanate. And IPDI (isophorone diisocyanate) -based isocyanate resin, isothiocyanate (resin), and the like.

  Ceramic slurries are obtained by uniformly mixing these components in addition to solidifying catalysts and initiators, antifoaming agents, surfactants, sintering aids, and other additives for improving characteristics. be able to. The slurry concentration (powder volume% with respect to the total volume of the slurry) of such a ceramic slurry is preferably 25 volume% or more and 75 volume% or less, more preferably 35 volume% or more and 75 volume% or less.

  Hereinafter, the process of producing the ceramic molded body 22 by the gel cast method will be described with reference to FIGS. FIG. 8 is a diagram showing an example of a molded body preparation step using a conductor material 26 having a linear shape in advance, and FIG. 9 shows another example of a molded body preparation step using a conductor material 26 having a linear shape in advance. FIG. 9B is a diagram illustrating an example of a ceramic molded body having a guide, and FIG. 10 is a diagram illustrating an example of a molded body preparation process using a conductive material 26 having fluidity. FIG. 11 is a diagram showing another example of a molded body preparation step using a conductive material having fluidity, FIG. 12 is a diagram showing another example of the molded body preparation step, and FIG. FIG. 14 is a diagram showing an example of a process for preparing a non-linear conductor material-containing ceramic molded body in FIG. 12, and FIG. 14 is a diagram showing another example of a process for preparing a non-linear conductor material-containing ceramic molded body in FIG. It is.

(Formed body preparation step 1)
In order to produce the ceramic molded body 22 by the gel casting method using the linear conductor material 26, first, a water-impermeable molding die 40 corresponding to the shape of the ceramic structure 2 is prepared. Then, the ceramic material slurry is supplied to a molding cavity in which a conductor material 26 having a linear shape is previously arranged, and the slurry is solidified to produce the linear conductor material-containing ceramic molded body. More specifically, as shown in FIG. 8, a linear conductor material 26 having a predetermined shape is arranged at a predetermined position in the molding cavity 42 of the mold 40 (step S1), and then ceramic slurry. 44 is solidified at a predetermined temperature and time (step S2), then released to obtain a gel wet molded body (step S3), and further dried under predetermined conditions (step S4). Can be obtained. In the obtained molded body 22, the linear conductors 26 are arranged in a predetermined form in the unfired ceramic material 24.

  In order to improve the positioning accuracy of the linear conductor material 26, the linear conductor material may be placed in a mold in a state in which the conductor material is wound around an unfired ceramic columnar body having a predetermined outer shape. Good. Such a ceramic molded body may be a sintered body. This is because the handling strength is high and the handling is excellent.

  Further, as shown in FIG. 9A, an unfired or fired ceramic molded body 60 including a guide 62 for winding the conductor material 26 can be used. FIG. 9A shows a manufacturing example of the conductor material-encapsulating ceramic molded body 22 using the ceramic molded body 60 for arranging the linear conductor material 26 in a winding shape in a sectional structure at each stage. Since the ceramic molded body 60 includes the guide 62, the conductor material 26 can be wound more accurately. The form of the guide 62 is not particularly limited as long as the winding state of the conductor material 26 around the ceramic molded body 60 can be regulated. For example, as shown in FIG. 9A, a concave portion that can accommodate a portion corresponding to a part of the cross section according to the outer shape of the conductor material 26 may be used. Further, for example, a convex portion that restricts both sides of the conductor material 26 so that the conductor material 26 shown in FIG. 9B (a) can pass, and the conductor material 26 shown in FIG. 9B (b) can be positioned by contacting the base. It is possible to adopt a form such as a convex part on one side and a concave part that accommodates or locks a part of the cross section of the conductor material 26 shown in FIG. Further, the conductor material 26 may be wound in one step in the outer circumferential direction, and the guide 62 may be formed so as to be wound in a plurality of steps.

  When the conductor material 26 is wound in a plurality of stages in the outer circumferential direction, if the accurate winding is achieved in the first stage, the winding accuracy in the second and subsequent stages can be secured to some extent. Further, as shown in FIG. 9A, when the conductor material 26 is wound in a plurality of stages, a concave portion that can also accommodate the conductor material 26 wound in the second and subsequent stages may be formed.

  The three-dimensional shape of the ceramic molded body 60 is not particularly limited as long as the target three-dimensional shape can be imparted to the conductor material 26. For example, it can be appropriately selected from arbitrary forms such as a columnar body, a plate-shaped body, and a cylindrical body having various cross-sectional shapes in addition to a circular shape.

  In addition, it is preferable to use the conductor material 26 that is insulation-coated with an inorganic material or the like so that the conductor materials 26 wound around the ceramic molded body 60 may contact each other. By doing so, it is possible to easily and precisely form a winding state.

  Such a ceramic molded body 60 can be manufactured by various ceramic molded body manufacturing methods such as a gel casting method, similarly to the ceramic structure 2 of the present invention. In particular, by using a molding die such as a gel cast method, the guide 62 can be formed with high accuracy, and as a result, the conductor material 26 can be arranged with high accuracy.

  Further, a temporary molded body having a concave portion 62 corresponding to the shape of the linear conductor material 26 is prepared in advance, and the linear conductor material 26 is disposed in the concave portion 62 and an additional ceramic slurry 44 is provided. May be molded by injecting into the concave part. By doing so, it is possible to easily hold a highly accurate conductor material in a winding state in the ceramic matrix.

(Formed body preparation step 2)
In addition, as shown in FIG. 10, the molded body preparation step prepares a linear cavity-containing ceramic molded body 48 including a ceramic material 24 and a linear cavity 46 corresponding to the linear shape in the ceramic material 24. The ceramic molded body 22 can be manufactured by filling the linear cavity 46 with a fluid conductive material (step S11). According to such a molded body preparation step, a linear conductor material 26 can be easily formed in a ceramic molded body even with a fluid conductor material 26 such as a conductor paste without using a linear material as the conductor material 26. it can. Moreover, since the fluid conductive material 26 is used, a linear structure having an arbitrary shape can be provided, and a high stress absorption ability can be provided. In this molded body preparation step, release from the mold 40, drying of the wet molded body, and the like may be performed in a timely manner.

  In order to prepare the linear cavity inclusion ceramic molded body 48, a method as shown in FIG. 10 can be adopted. That is, after a flexible linear material 49 such as a resin wire material or a resin tube material provided with a linear shape such as a coil shape corresponding to the linear cavity 46 is arranged in the cavity 42 for the ceramic molded body After the ceramic slurry 44 is filled in the mold 40 and solidified, the linear material 49 may be pulled out from the solidified body. By doing so, a linear cavity 46 such as a coil shape is formed in the removed portion of the linear material 49. The linear material 49 for forming the linear cavity 46 is not limited to resin, but it is preferable to use a material with low surface energy such as polytetrafluoroethylene, silicone resin, or silicone rubber. The linear material 49 may be pulled out after the solidified body is released from the mold 40 or before that.

  Furthermore, the linear cavity inclusion ceramic molded body 48 can be prepared, for example, by the method shown in FIG. FIG. 11 is a cross-sectional view of a manufacturing example of a linear cavity-containing ceramic molded body 48 including a linear cavity 46 for filling a fluid conductive material 26 in a winding shape and a conductive material-containing ceramic molded body 22 at each stage. It shows with. In this method, a set 80 of two or more cavity-forming ceramic bodies 82 (in FIG. 11, two sets of 82a and 82b are illustrated) that form the linear cavity 46 by integration is prepared. it can. A set 80 of these ceramic bodies 82 for forming a cavity is configured so that the linear cavity 46 can be formed when a predetermined surface is attached and integrated by bonding or the like. As described above, the set 80 including the plurality of cavity-forming ceramic bodies 82 forms the linear cavity 46, so that the linear cavity 46 having a complicated shape can be accurately formed. The ceramic body 82 may be an unfired body or an already fired body.

  In particular, when at least one of the ceramic bodies 82 constituting the set 80 is obtained as a ceramic molded body by a molding die by a gel cast method or the like, similar to the ceramic structure 2 of the present invention, the shape of the linear cavity 46 is changed to the molding mold. Therefore, the position and shape of the linear cavity 46 can be realized with high dimensional accuracy. In FIG. 11, the ceramic body 82a constituting the concave portion 84 that substantially constitutes the linear cavity 46 is produced by a gel casting method using a mold having a cavity corresponding to the ceramic body 82a. For this reason, a position and a shape can be reliably realized with high dimensional accuracy.

  The integration of the plurality of cavity-forming ceramic bodies 82 is not particularly limited as long as it is integrated so that the conductive material 26 having fluidity can be filled. Absent. Therefore, mechanical integration by pressing in a mold or the like may be performed, or integration by a joining technique applicable to ceramics such as a binder and firing may be performed.

  The set 80 of the ceramic bodies 82 for forming the cavity is not particularly limited in terms of the combination mode and the number of components as long as the set 80 is formed in a plurality so as to be integrated to form the linear cavity 46. For example, as shown in FIG. 11, the linear cavity 46 may be configured by arranging ceramic bodies 82 a and 82 b to face each other along the length direction of the linear cavity 46, or the length of the linear cavity 46. The linear cavity 46 may be formed by disposing the ceramic bodies 82 so as to face each other along a direction intersecting the direction (for example, a direction intersecting substantially at right angles).

  Further, for example, the linear cavity 46 may be formed by attaching the openings of the concave portions formed on the opposing surfaces of two or more cavity-forming ceramic bodies 82 arranged in an opposing manner. Further, for example, one or two or more first cavity-forming ceramic bodies 82 having concave portions 84 corresponding to the linear cavities 46 on the surface, and wall surfaces 86 that shield the opening portions of the concave portions 84 are provided. One or two or more second cavity forming ceramic bodies 82 can be used. These cavity-forming ceramic bodies 82 preferably constitute the entire linear cavity 46, but may constitute a part thereof.

  An integrated body (integrated body) 90 of these cavity-forming ceramic bodies 82 constituting the set 80 can constitute a part or the whole of the linear cavity-containing ceramic molded body 48. As shown in FIG. 11, when the integrated body 90 constitutes the entire linear cavity-containing ceramic molded body 48, the integrated body 90 is itself a linear cavity-containing ceramic molded body 48, and the ceramic molded body The outer shape of the body 48 is provided. That is, each ceramic body 82 has an outer shape that forms the outer shape of the conductor material-containing ceramic molded body 48 by integration. When the integrated body 90 forms the entire outer shape of the linear cavity-containing ceramic molded body 48, the conductor material-containing ceramic molded body 22 is obtained by filling the linear cavity 46 of the integrated body 90 with the conductive material. be able to.

  On the other hand, when the integrated body 90 constitutes only a part of the linear cavity inclusion ceramic molded body 48, the ceramic slurry 44 is further supplied to the integrated body 90 and the final linear cavity embedded molded body 48 or A conductive material-containing ceramic molded body 22 can be obtained. For example, as shown in FIG. 11, the linear cavity 46 of the integrated body 90 is filled with a fluid conductive material 26, and this integrated body 90 is formed into a molding die for forming a conductive material-containing ceramic molded body 22. The ceramic slurry 44 is placed in the cavity 40 and injected into the cavity 42 to obtain a linear cavity-containing ceramic molded body 48. The integrated body 90 is placed in a mold for obtaining the conductor material-encapsulating ceramic molded body 22 and filled with ceramic slurry to obtain the linear cavity-encapsulating ceramic molded body 48, and then the conductor material 26. The conductive material-encapsulating ceramic formed body 22 may be obtained by filling

  Further, at least two of the linear cavity forming ceramic bodies 82 constituting the set 80 can be made of ceramic materials exhibiting different compositions or characteristics by subsequent firing. By doing this, it may be possible to improve the inductor characteristics.

  In the simplest case, the set 80 of the ceramic molded bodies 82 for forming the linear cavities has a concave shape substantially corresponding to the hollow shape of the linear cavities 46 along the length direction of the linear cavities 46 as illustrated in FIG. The first cavity-forming ceramic body 82a having the portion 84 on the outer peripheral surface, and the cylindrical wall surface 86 having the inner peripheral surface that forms the linear cavity 46 by shielding the opening of the concave portion. The linear cavity-containing ceramic molded body 48 can be constituted from the two cavity-forming ceramic bodies 82b. In addition, in FIG. 11, the recessed part corresponding to the linear cavity 46 is formed in the internal peripheral surface of the cylindrical body located in the outer peripheral side, and it is set as the 1st cavity formation ceramic body, and the outer peripheral surface of an inner peripheral side is used. It is good also as a 2nd ceramic body for cavity formation which has a wall surface which shields the opening part of a concave part.

  In FIG. 11, the spiral or coiled linear cavity 46 is constituted by two linear cavity forming ceramic bodies 82a and 82b, but the present invention is not limited to this. The linear cavity 46 may have another linear form, or three or four or more linear cavity forming ceramic bodies 82 may be appropriately combined. Further, it is not always necessary to arrange and integrate linear cavity forming ceramic bodies on the inner side and the outer side as shown in FIG. It can be changed as appropriate.

(Formed body preparation step 3)
As shown in FIG. 12, the molded body preparation step includes a non-linear conductor material-containing ceramic molded body 50 including a ceramic material 24 and a non-linear conductor material 26 having a shape that can be processed into a desired linear form. Is prepared (step S20), and a part of the non-linear conductor material 26 in the molded body 50 is removed by cutting or the like to obtain a desired linear form (step S21). By supplying a slurry of the ceramic material to the removed portion and solidifying the slurry (step S22), a process for preparing the ceramic molded body 22 can be performed.

  According to such a molded body preparation step, it is not necessary to give the final linear form to the linear member such as the linear conductor material 26 or the linear cavity forming member 52 from the beginning. It is possible to omit the provision of a linear form to the non-linear form and to dispose the non-linear form of the conductor material 26 in the molding cavity 42. Difficulties such as positioning and fixing can be avoided or reduced. Furthermore, since the final linear form is provided from the non-linear form by secondary processing such as cutting or extrusion, the degree of freedom of the linear form can be increased. In this molded body preparation step, release from the mold 40, drying of the wet molded body, and the like may be performed in a timely manner.

  Examples of the non-linear conductor material 26 include a conductor material 26 having a male screw threaded portion (screw shaft) as shown in FIG. Such a male screw-like body has a spiral thread on the outer periphery, and the conductor material 26 in a linear form consisting only of the spiral thread is obtained by removing the inner part of the shaft body so as to leave this thread. Can be obtained. The male screw-like body only needs to have a male screw portion, and the inside of the shaft body does not need to be solid and may be a cavity.

  Such a non-linear conductor material 26 can be obtained by molding a fluid conductor material 26 such as a conductive paste. A non-linear conductor material-containing ceramic molded body 50 containing such a conductor material 26 is prepared. For example, the method shown in FIGS. 13 and 14 can be employed.

  In the method shown in FIG. 13, a conductor material 26 having such a non-linear shape is formed in advance with a fluid conductor material 26 such as a conductor paste, and this conductor material compact is placed in a molding cavity 42 to be ceramic slurry 44. Is a method of filling and solidifying. Further, the method shown in FIG. 14 is obtained by placing the cavity forming member 52 corresponding to the non-linear form in the molding cavity 42 and filling and hardening the ceramic slurry 44, and then removing the cavity forming member 52. The conductive material 26 having a non-linear shape may be formed in situ in the molded body 50 by filling the cavity 54 with a conductive paste or the like. The cavity forming member 52 for forming the non-linear cavity 54 can be easily removed from the molded body by using a male screw-like body.

  To process the non-linear form of the conductor material 26 into a linear form, as shown in FIG. 12, mechanical cutting of a portion unnecessary for the linear form (for example, the inner part of the male screw-like body) is performed. Or by cutting, so that only the spiral thread portion remains in the ceramic molded body. For removing the unnecessary portion, for example, the inside of the conductor material 26 may be cut with a drill having an outer diameter smaller than that of the male screw-like body.

(Unsintered ceramic compact)
The unsintered ceramic molded body of the present invention is a ceramic molded body 22 obtained in such a ceramic molded body preparation step. The ceramic molded body 22 is a conductor material 26 including a matrix 24 of an unsintered ceramic material and a conductor component, and a conductor material 26 having a stress absorbing ability capable of absorbing contraction stress related to the conductor material. The conductor material 26 can be included in the ceramic material 24 in a linear form. As already described, the ceramic molded body 22 can be provided with various stress absorption capabilities.

(Baking process)
Next, the ceramic molded body 22 is sintered. Conditions for sintering can be set as appropriate depending on the type of ceramic powder and the like. In the firing step, the molded body 22 contracts as the ceramic material is sintered, and the shrinkage stress acts on the molded body. In the vicinity of the interface with the conductor material 26 in the linear form, the stress absorption capability of the conductor material 26 absorbs the shrinkage stress, and the generation of tensile stress in the ceramic matrix 4 near the interface of the conductor material 26 can be suppressed or avoided. .

  When the stress absorbing ability is imparted by the hollow portions 30 such as the through-hole portions 30a and the dispersed hole portions 30b, the hollow portions 30 are deformed or reduced to absorb the contraction stress. In addition, when the stress absorbing ability is imparted by the volume reducing component 32c, the volume reducing component 32c is burned away, so that a hollow portion corresponding to the volume reducing component 32c is formed in-situ. Thereby, similarly to the case where the hollow portion 30 is provided, the contraction stress can be absorbed by the deformation or reduction of the hollow portion. Therefore, the ceramic structure 2 can be obtained while suppressing or avoiding cracks and cracks in the ceramic matrix 4. In addition, a decrease in strength over time and delayed fracture of the ceramic structure 2 can be suppressed or avoided.

  As already described, when the conductor material 26 having a linear shape has flexibility, the contraction stress can be absorbed more effectively in combination with the deformation of the conductor material 26. Even when the linear conductor material 26 is formed by molding a conductor paste or the like, the contraction stress can be effectively absorbed by the mobility of the conductor component in the firing step.

  According to the present invention, if the shrinkage rate when the linear conductor ceramic formed body is sintered is 15% or more and 45% or less in this way, the shrinkage stress generated in the ceramic matrix 4 is absorbed in the firing step to absorb the ceramic. The structure 2 can be obtained. This is because the shrinkage rate is unlikely to be less than 15%, and if it exceeds 45%, sintering becomes insufficient. More preferably, the shrinkage rate is 35% or less.

  Furthermore, according to the present invention, it is possible to absorb the stress corresponding to the shrinkage of the ceramic structure 2 in the cooling step subsequent to the firing step.

  In the firing step, the conductor material 26 may finally have a form as the conductor 6 through deformation or reduction of at least a part of the hollow portion 30 in the conductor material 26 or disappearance of at least a part of the volume reducing component 33. it can. At least a part of the conductor 6 in the ceramic structure 2 after sintering and the conductor material 26 before sintering are different in form. That is, in the case of the conductor 6, when the conductor material 26 includes the hollow portion 30, the hollow portion 30 of the conductor material 26 is deformed or reduced and includes the volume reducing component 33. The hollow portion is formed by the disappearance of the volume reducing component 32 or the like, and then the hollow portion is deformed or reduced. Note that the reduction of the hollow portion 30 (including the hollow portion due to the disappearance of the volume reducing component 32) includes a mode in which the hollow portion 30 is closed.

  As described above, according to the method for manufacturing a ceramic structure of the present invention, the ceramic structure 2 including the conductor 6 therein can be efficiently manufactured while suppressing defects caused by sintering. Further, by using an in-situ solidification method such as a gel cast method, it is possible to efficiently manufacture minute parts and parts that require molding accuracy. Therefore, the manufacturing method of the present invention can be used as a manufacturing method of electronic parts such as an inductor, a noise filter, a coaxial resonator, a coupler, a balun, and a delay line.

(Ceramic structure)
The ceramic structure of the present invention can include a sintered ceramic matrix 4 and a linear conductor 6 included in the sintered ceramic matrix 4. The ceramic matrix 4 may be dense or porous. The density and porosity are appropriately set according to the application of the ceramic structure 2.

  As described above, the conductor 6 in the ceramic structure 2 is obtained by deforming or disappearing the hollow portion 30 or the volume reducing component 32 of the linear conductor 26 before sintering as the ceramic material 24 is sintered. It is a thing. Therefore, the conductor 6 can be provided with a hollow part or its trace as a result. The hollow portion in the conductor 6 and the trace thereof include the hollow portion 30 in the conductor material 26, the hollow portion derived from the volume reducing component, and a portion in which these hollow portions are deformed, reduced, or closed.

  The ceramic structure 2 of the present invention is a structure that is excellent in mechanical strength and electrical characteristics by suppressing defects caused by sintering. For this reason, it is a preferable structure for a minute electronic component or a minute-shaped electronic component. Therefore, the ceramic structure of the present invention can be used as an electronic component such as an inductor, a noise filter, a coaxial resonator, a coupler, a balun, or a delay line.

  Hereinafter, the present invention will be specifically described with reference to examples. It should be noted that the following examples are illustrative of the present invention and are not intended to limit the present invention.

(1) Production of Ceramic Molded Body by Gel Casting Method A ceramic slurry used for the gel casting method was prepared as follows. That is, 100 parts by weight of Ni, Zn, Cu-based ferrite powder as raw material powder, 2.5 parts of triacetin as a dispersion medium, 22.5 parts by weight of dimethyl glutarate, 0.2 part of ethylene glycol, gelling agent A mixture of 2.0 parts by weight of (polymethylene polyphenyl polyisocyanate), 3 parts by weight of a dispersant (polymer carboxylic acid) and 0.1 part by weight of 6-dimethylamino-1-hexanol as a catalyst was used.

  Next, an Ag coil was prepared with a wire diameter of 0.1 mm, a coil length of 1 mm, a coil diameter of 1 mm, a number of turns of 10 times, and a length of a straight portion at both ends of the coil of 0.5 mm. Moreover, the conductor part of the coil was a cylindrical body (thickness 25 μm) and provided with a through hole (diameter 50 μm) penetrating in the axial direction. This coil was placed in advance in an aluminum alloy mold (about 2 mm × 2 mm × 2 mm), and the prepared slurry was cast at room temperature and left at room temperature for 1 hour. Subsequently, it was left to stand at 40 ° C. for 30 minutes to advance solidification and release. Subsequently, it was left at 90 ° C. for 1 hour to obtain a ceramic molded body. In addition, the coil which does not have a through-hole and a resin layer inside by the same material and the same form was prepared, and the ceramic molded body of the comparative example was produced by the method similar to an Example.

(Baking process)
These ceramic molded bodies were fired at 900 ° C. in the atmosphere to sinter the ceramic matrix.

  The sintered body of the example shrunk by about 30% in the firing process. However, regardless of the shrinkage, the sintered body includes the coil maintaining the initial form, and secures an appropriate strength without causing cracks in the vicinity of the coil. This was a sintered ceramic body. Moreover, when the through-hole part inside a linear conductor was observed, it was in a state where the inside was wrinkled, and the through-hole was deformed or partially compressed to some extent. On the other hand, in the comparative example, the ceramic molded body collapsed in the firing step, and a ceramic structure could not be obtained.

  From the above, it is possible to effectively suppress or avoid cracking of the ceramic structure by absorbing the shrinkage stress by providing the lead wire itself with a stress absorbing portion that absorbs the shrinkage stress generated during sintering. I knew it was possible.

It is a figure which shows an example of the process of the manufacturing method of the ceramic structure of this invention. It is a figure which shows an example of the ceramic structure of this invention, Fig.2 (a) shows the external shape of a ceramic structure, FIG.2 (b) is the sectional drawing. It is a figure which shows the cross-section of the ceramic molded body which is a precursor of the ceramic structure of this invention. It is a figure which shows the example (a)-(e) of conductor material, FIG. 4 (a) and FIG.4 (b) are axial direction sectional drawings of conductor material, FIG.4 (c) and FIG.4 (d). ) Is a cross-sectional view of the conductor material, and FIG. 4E is a view in which an axial cross-sectional view and a cross-sectional view of the conductor material are combined. It is a figure which shows the other example of a conductor material, and Fig.5 (a)-(c) is an axial sectional view of a conductor material. It is a figure which shows the other example of a conductor material, and Fig.6 (a) and FIG.6 (b) are axial direction sectional drawings of a conductor material. It is a figure which shows the other example of a conductor material, and Fig.7 (a) and FIG.7 (b) are axial direction sectional drawings of a conductor material. It is a figure which shows an example of the molded object preparation process using the conductor material which has a linear form previously. It is a figure which shows another example of the molded object preparation process using the conductor material which has a linear form previously. It is a figure which shows the example of the ceramic molded body which has a guide. It is a figure which shows an example of the molded object preparation process using the conductor material which has fluidity | liquidity. It is a figure which shows another example of the molded object preparation process using the conductor material which has fluidity | liquidity. It is a figure which shows another example of a molded object preparation process. It is a figure which shows an example of the process of preparing the non-linear conductor material inclusion ceramic molded object in FIG. It is a figure which shows another example of the process of preparing the non-linear conductor material inclusion ceramic molded object in FIG.

Explanation of symbols

2 Ceramic structure, 4 Sintered ceramic matrix, 6 conductor, 22 ceramic molded body, 24 matrix of unsintered ceramic material, 26 conductor material, 28 conductor component matrix, 30 hollow part, 30a through hole part, 30b dispersion Shaped hole part, 32 volume reducing component, 34 weak part, 40 mold, 42 molding cavity, 44 ceramic slurry, 46 linear cavity, 48 linear cavity encapsulated ceramic molded body, 49 linear material, 50 non-linear conductor material Encapsulated ceramic molded body, 52 Non-linear cavity forming member, 54 Non-linear cavity, 60 Ceramic columnar body, 62 Guide, 80 Linear cavity forming ceramic body set, 82, 82a, 82b Linear cavity forming ceramic body , 84 concave part, 86 wall surface 90 integrated body

Claims (28)

A method for producing a ceramic structure having a conductor in a linear form inside,
A ceramic material produced by sintering a ceramic matrix of the ceramic structure, and a conductor material including a conductor component, and a conductor material having a stress absorbing ability capable of absorbing contraction stress related to the conductor material inside thereof. A formed body preparation step of preparing a conductor material-containing ceramic molded body including the conductor material in a linear form in the ceramic material;
A firing step of sintering the conductive material-containing ceramic molded body;
A manufacturing method comprising:   2. The manufacturing method according to claim 1, wherein the formed body preparation step is a step of preparing the conductive material-encapsulated ceramic formed body included in a state where the surface of the conductive material is in close contact with the ceramic material.   The manufacturing method of Claim 1 or 2 which relieves the shrinkage stress which generate | occur | produces in the surface vicinity of the said conductor material at the said ceramic baking process.   The said conductor material is a manufacturing method in any one of Claims 1-3 which has the hollow part which can be deform | transformed or reduced by the said contraction stress.   The manufacturing method according to claim 4, wherein the hollow portion includes a through-hole portion penetrating the conductor material in a longitudinal direction and / or a large number of hole portions dispersed in the conductor material.   The said conductor material is a manufacturing method in any one of Claims 1-5 containing the volume reduction component which can be reduced by burning or sublimation in the said baking process.   The manufacturing method according to claim 1, wherein the linear form has a spiral form.   The molded body preparation step includes using a ceramic slurry containing ceramic powder, an organic dispersion medium having a reactive functional group, and a gelling agent, and solidifying by a reaction between the organic dispersion medium and the gelling agent. The manufacturing method in any one of Claims 1-7 which is a process of producing the inclusion ceramic molded object.   The manufacturing method according to claim 1, wherein the conductor material is a linear member having a linear shape in advance.   The manufacturing method according to claim 9, wherein the linear member has flexibility.   The forming body preparing step is a step of supplying the ceramic material slurry to a forming cavity provided with the linear member and solidifying the slurry to produce the conductive material-containing ceramic formed body. The manufacturing method according to 9 or 10.   The said molded object preparation process is a process including arrange | positioning in the said cavity for shaping | molding in the state in which the said linear member was wound around the unbaked or already-baked ceramic molded object of the predetermined | prescribed external shape. Production method.   The manufacturing method according to claim 12, wherein the ceramic molded body includes a guide for winding the linear member. The molded body preparation step includes
Preparing a linear cavity-containing ceramic molded body comprising the ceramic material and a linear cavity corresponding to the linear form in the ceramic material, and filling the linear cavity with the fluid conductive material The manufacturing method according to any one of claims 1 to 8, which is a step of preparing the conductive material-containing ceramic molded body.   The forming body preparation step uses two or more cavity forming ceramic bodies that form the linear cavity by integration, and the conductor is formed in the linear cavity that is formed by integrating these cavity forming ceramic bodies. The manufacturing method of Claim 14 which is a process including filling with a material.   The two or more cavity-forming ceramic bodies shield one or two or more first cavity-forming ceramic bodies having concave portions corresponding to the linear cavities on the surface, and openings of the concave portions. The manufacturing method of Claim 15 which consists of 1 or 2 or more 2nd cavity formation ceramic molded object which has a wall surface to perform.   The manufacturing method according to claim 15 or 16, wherein each of the two or more cavity-forming ceramic bodies has an outer shape that forms an outer shape of the conductive material-containing ceramic molded body by the integration.   The forming body preparing step prepares a non-linear conductor material-containing ceramic formed body including the ceramic material and the non-linear form of the conductor material having a shape that can be processed into the linear form in the ceramic material. After removing a part of the non-linear conductor material to form the linear form, the slurry is supplied to the removed portion of the conductor material, and the slurry is solidified to solidify the linear material. The method according to any one of claims 1 to 8, which is a step of preparing a conductive material-containing ceramic molded body.   The non-linear conductor material-containing ceramic molded body, and the non-linear cavity-containing ceramic molded body having a cavity corresponding to the non-linear form in the ceramic material, the fluid conductor material in the non-linear cavity. The method according to claim 18, wherein the method is prepared by filling. The linear form has a spiral form;
The manufacturing method according to claim 18 or 19, wherein the non-linear form is a columnar shape or a cylindrical shape including a spiral convex portion on an outer periphery.   The manufacturing method according to any one of claims 1 to 20, wherein the conductive material includes one or more selected from the group consisting of Ag, Au, Pt, Cu, Ni, Pd, and Rh.   The manufacturing method in any one of Claims 1-21 whose shrinkage | contraction rate in the said baking process of the said inorganic powder molded object is 15% or more and 45% or less.   The manufacturing method according to claim 1, wherein the manufacturing method is an electronic component manufacturing method.   A ceramic structure obtained by the production method according to claim 1. A ceramic structure,
A sintered ceramic matrix;
A conductor in a linear form encapsulated in the sintered ceramic matrix, and a conductor having a hollow portion or a trace thereof inside thereof,
A structure comprising:   26. The structure according to claim 25, wherein the hollow portion or the trace thereof includes a portion in which the hollow portion existing in the conductor material before sintering is deformed, reduced, or closed by the sintering. An unsintered ceramic molded body,
A matrix of unsintered ceramic material,
A conductor material including a conductor component, and a conductor material having a stress absorbing ability capable of absorbing contraction stress applied to the conductor material on the inside thereof;
With
A molded body containing the conductor material in a linear form in the ceramic material.   28. The molded body according to claim 27, wherein the conductor material includes any one selected from a volume reducing component that can be reduced by burning or sublimation in association with firing of the hollow portion and the ceramic material.