JP5013144B2 - Manufacturing method of ceramic electronic component - Google Patents

Description

The present invention relates to a method for manufacturing a ceramic electronic component in which a chip-type electronic component is mounted on a ceramic molded body.

  When mounting an electronic component on a ceramic substrate, usually, for example, as shown in FIG. 10, a solder paste 53 is applied to a surface conductor portion 52 of a fired ceramic substrate 51, and a chip type is formed on the surface conductor portion 52. After the electronic component 54 is mounted by the mounter, a reflow process is performed on the ceramic substrate 51 on which the chip-type electronic component 54 is mounted, so that the terminal electrodes 55 of the chip-type electronic component 54 are placed on the surface conductor 52 on the ceramic substrate 51. It is made to join and fix via solder (refer to patent documents 1).

  However, in the conventional method for manufacturing a ceramic substrate, since electronic components are mounted via solder, for example, a solder reflow process is required, and the process becomes complicated.

In addition, solder mounting has a problem of so-called solder flash in which short-circuit failure occurs between adjacent electrodes due to the inflow of solder.
From such a viewpoint, when manufacturing a ceramic electronic component on which a chip-type electronic component is mounted, there is a demand for a more efficient and highly reliable method for manufacturing a ceramic electronic component.
JP-A 61-263297

The present invention has been made to solve the above-mentioned problems, and it is possible to efficiently and reliably secure a chip-type electronic component on a surface conductor without requiring a mounting process using a bonding material such as solder or a conductive adhesive. It is an object of the present invention to provide a method for manufacturing a ceramic electronic component that can be mounted on a board.

In order to solve the above problems, a method for manufacturing a ceramic electronic component according to claim 1 of the present application includes:
A base material layer comprising a surface conductor and containing ceramic powder and a glass material;
It is disposed so as to be in contact with at least one main surface of the base material layer and is not burned down when fired in a low oxygen atmosphere, but is burned down when fired at a higher oxygen partial pressure than the low oxygen atmosphere. A constraining layer comprising a via-hole conductor connected to the surface conductor;
A laminate production step of producing an unfired laminate comprising:
A chip-type electronic component mounting step for mounting the chip-type electronic component on the constraining layer so that the terminal electrode thereof is in contact with the via-hole conductor;
The surface conductor and the via-hole conductor of the base material layer, and the terminal electrode and the via-hole conductor of the chip-type electronic component are fixed by sintering, respectively, and the surface conductor and the terminal electrode are interposed via the via-hole conductor. And a firing step of firing the unfired laminate so as to be in an electrically connected state,
The firing step includes
A first firing step of firing the unfired laminate in the low-oxygen atmosphere and sintering the base material layer without burning out the burned material constituting the constraining layer;
And a second firing step in which firing is performed under a higher oxygen partial pressure than in the first firing step, and the burnt material constituting the constraining layer is burned off.

  In the method of manufacturing a ceramic electronic component according to claim 2, in the laminate manufacturing step, a recess is formed in a region on the surface of the constraining layer where the chip-type electronic component is mounted and the via hole conductor is included. It is characterized by forming.

  The method of manufacturing a ceramic electronic component according to claim 3 is characterized in that a recess is formed also in a region of the surface of the base material layer that is in contact with the back side of the region where the recess of the constraining layer is formed. .

  According to a fourth aspect of the present invention, there is provided a method for manufacturing a ceramic electronic component, comprising: pressing a mold having a convex portion having a size corresponding to the chip-type electronic component from the upper surface side of the constraining layer in the laminate manufacturing step. The recess is formed.

  The method for manufacturing a ceramic electronic component according to claim 5 is characterized in that, in the first firing step, firing is performed so that the glass material contained in the base material layer penetrates into the constraining layer.

  The method for manufacturing a ceramic electronic component according to claim 6 is characterized in that the burned-out material is carbon powder.

The method for manufacturing a ceramic electronic component according to claim 7 is:
The base material layer includes a binder, and
A binder removal step of removing the binder contained in the base material layer before the first firing step in the firing step;
The binder removal step is performed in an oxygen-containing atmosphere and at a temperature at which the burnout material does not burn out.

  In the method of manufacturing a ceramic electronic component according to claim 8, in the laminate manufacturing step, the constraining layer is in contact with at least one main surface of the base material layer including a sheet containing the burned-out material as a main component. It is formed by arranging.

  In the method of manufacturing a ceramic electronic component according to claim 9, in the laminate manufacturing step, the constraining layer applies a paste containing the burned material as a main component to at least one main surface of the base material layer. It is characterized by being formed by.

In the method for manufacturing a ceramic electronic component according to the present invention, a chip-type electronic component is provided on a green laminate including a base material layer having a surface conductor and a constraining layer having a via-hole conductor, and a terminal electrode is a via-hole. Since it is mounted so as to be in contact with the conductor and the unfired laminate is fired in that state, the surface conductor and via-hole conductor of the base material layer, and the terminal electrode and via-hole conductor of the chip-type electronic component in the firing process However, they are fixed by sintering, and the surface conductor and the terminal electrode can be electrically connected through the via-hole conductor.
As a result, it is not necessary to perform mounting using solder as in the prior art, and the manufacturing process can be simplified. Further, since it is not necessary to use solder, it is possible to prevent the occurrence of solder flash.

  In addition, since firing is performed with a constraining layer interposed between the base material layer and the chip-type electronic component, shrinkage in the planar direction of the base material layer in the first firing process is suppressed. Since the influence of the shrinkage of the base material layer is not directly transmitted to the chip type electronic component, it is possible to prevent the chip type electronic component and the ceramic molded body (base material layer after sintering) from being cracked.

  In addition, since the chip-type electronic component is fired in a state where it does not directly contact the base material layer (ceramic molded body), the influence of the difference in thermal expansion coefficient between the chip-type electronic component and the ceramic molded body is small, In this respect as well, it is possible to reduce the possibility of cracks and the like occurring in the chip-type electronic component and the ceramic molded body.

Further, as in the method of manufacturing a ceramic electronic component according to claim 2, when the chip-type electronic component on the surface of the constraining layer is mounted and a recess is formed in the region where the via-hole conductor is disposed This can contribute to the reduction of the height and thickness of the product as a whole.
In addition, the constraining layer is formed only in the region where the chip type electronic component is mounted, and the thickness of the constraining layer is ensured in other parts, so that the constraining layer exhibits sufficient restraining force. Therefore, it is possible to manufacture a ceramic electronic component with high dimensional accuracy by suppressing shrinkage in the planar direction.

  Further, as in the method for manufacturing a ceramic electronic component according to claim 3, when the concave portion is formed also in the region of the surface of the base material layer that is in contact with the back surface side of the region where the concave portion of the constraining layer is formed, It becomes possible to increase the depth of the recess as a whole, and accordingly, it becomes possible to promote the reduction in thickness and height of the product.

  Further, as in the method for manufacturing a ceramic electronic component according to claim 4, when a concave portion is formed by pressing a mold having a convex portion having a size corresponding to the chip-type electronic component from the upper surface of the constraining layer, The concave portions can be easily and reliably formed in both the layer or the constraining layer and the base material layer, and the present invention can be more effectively realized.

In the method for manufacturing a ceramic electronic component according to claim 5, in the first firing step, the glass material contained in the base material layer penetrates into the constraining layer to form a permeation layer. Then, the constraining layer and the base material layer are strongly bonded via the permeation layer, and the permeation layer reliably suppresses and prevents shrinkage of the base material layer in the planar direction in the first firing step.
In order to obtain the restraining force more reliably, it is desirable that the glass material of the base material layer penetrates into the constraining layer reliably. For that purpose, the constraining layer should be disposed so as to be in close contact with the base material layer. Is desirable.

  Further, when the carbon powder is used as the burned-out material as in the method for producing a ceramic electronic component of claim 6, the carbon powder does not burn when fired in a low oxygen partial pressure atmosphere in the first firing step. And since it does not shrink, the function which suppresses the baking shrinkage of a base material layer is fully exhibited. Further, in the second firing step, when firing is performed under a condition with a high oxygen partial pressure, it is burned and burned out. Therefore, various ceramic electronic components such as a ceramic substrate having high dimensional accuracy can be efficiently obtained through the constraining firing process without requiring a process for removing the constraining layer after the second firing process. This makes it possible to make the present invention more effective.

  In addition, as a carbon powder, it is desirable to use a thing with the particle size of the range of 0.1-100 micrometers. This is because when the particle size is 100 μm or less, a large restraining force can be obtained, and when the particle size is 0.1 μm or more, it is easily burned out in the second baking step.

In the method for manufacturing a ceramic electronic component according to claim 7, since the binder removal step is performed in an oxygen-containing atmosphere and at a temperature at which the burned-out material is not burned out before the first firing step. It is possible to smoothly carry out the first firing step of removing the binder contained in the binder in the binder removal step and performing the subsequent restraint firing and the second firing step of burning off the burned material.
The oxygen-containing atmosphere when performing the binder removal step is exemplified by an air atmosphere, an atmosphere in which air is introduced into an inert gas, or the like, but usually, a condition with a high oxygen partial pressure, such as an air atmosphere. The binder removal can be carried out more efficiently if carried out below.

  Further, in the present invention, as a method of forming the constraining layer, as in claim 8, a sheet containing a burned-out material is prepared in advance and disposed so as to be in contact with at least one main surface of the base material layer. The method of apply | coating the paste containing a burning material like at least one main surface of a base material layer etc. is mentioned.

It is a figure which shows the multilayer ceramic substrate (ceramic electronic component) manufactured by the manufacturing method of the ceramic electronic component of this invention. It is a figure which shows the unbaking laminated body provided with the constrained layer produced at the process of manufacturing the ceramic substrate of FIG. It is a figure which shows the state which mounted the multilayer ceramic capacitor as a chip-type electronic component in the unbaking laminated body of FIG. It is a figure which shows the other multilayer ceramic substrate manufactured by the manufacturing method of the ceramic electronic component of this invention. It is a figure which shows the unbaking laminated body provided with the constrained layer produced at the process of manufacturing the ceramic substrate of FIG. It is a figure which shows the state which is pressing the unbaking laminated body using the metal mold | die in 1 process of the manufacturing method of the multilayer ceramic substrate concerning Example 2 of this invention. It is a figure which shows the state after pressing an unbaking laminated body using a metal mold | die in 1 process of the manufacturing method of the multilayer ceramic substrate concerning Example 2 of this invention. It is a figure which shows the state which mounted the multilayer ceramic capacitor as a chip-type electronic component in the unbaking laminated body of FIG. It is a figure which shows the modification of the ceramic multilayer substrate of Example 2 manufactured by the manufacturing method of the ceramic electronic component of this invention . It is a figure explaining the mounting method to the ceramic substrate of the conventional electronic component.

DESCRIPTION OF SYMBOLS 1 Insulating ceramic layer 1a Ceramic green sheet for board | substrates 2 Conductor part 3a, 3b Mounting electronic component 10 Connection conductor 10a Via-hole conductor for connection conductor 11 Multilayer ceramic capacitor (chip type electronic component)
12 Through-hole 13 Terminal electrode 15 Mold 16 Convex part 21 Surface conductor (external conductor)
21a Unsintered outer conductor 22 Interlayer conductor (inner conductor)
22a Unsintered inner conductor 23 Via hole conductor (interlayer connection via hole conductor)
23a Unsintered via-hole conductor 31 Constrained layer 32 Unsintered laminate 33 Constrained layer through-hole (constrained layer through-hole)
40 Concave part A, B Ceramic electronic component (multilayer ceramic substrate)

  Hereinafter, the features of the present invention will be described in more detail with reference to examples of the present invention.

FIG. 1 is a view showing a ceramic electronic component (multilayer ceramic substrate) manufactured by the method for manufacturing a ceramic electronic component of the present invention.
A multilayer ceramic substrate A shown in FIG. 1 includes a chip-type electronic component 11 having terminal electrodes 13 (this is a multilayer ceramic substrate body in this embodiment 1) 20 having surface conductors 21 and interlayer conductors 22 (this example). In Example 1, a multilayer ceramic substrate having a structure on which a multilayer ceramic capacitor) is mounted.

  The multilayer ceramic substrate body 20 includes a plurality of insulating ceramic layers 1 made of a low-temperature sintered ceramic raw material composition containing ceramic powder and a glass material, an interlayer conductor 22, a surface conductor 21 disposed on the surface, and the like. The conductor part 2 is provided.

  As the low-temperature sintered ceramic composition constituting the insulating ceramic layer 1, for example, a low-temperature sintered ceramic composition in which an alumina-based ceramic powder and a borosilicate glass-based glass powder are blended is used.

  The conductor portion 2 includes the surface conductor 21 (outer conductor) described above, the interlayer conductor (inner conductor) 22 disposed between the plurality of insulating ceramic layers 1 and 1 joined to each other, and the interlayer conductors 22. Alternatively, a via hole conductor (interlayer connection via hole conductor) 23 that connects the surface conductor 21 and the interlayer conductor 22 is formed.

  The surface conductor 21 and the interlayer conductor 22 are formed by firing a surface conductor pattern and an internal conductor pattern formed by printing a conductive paste (for example, a silver-based conductive paste). The via-hole conductor 23 is formed, for example, by filling a through hole with a conductive paste or conductor powder and firing it.

In this multilayer ceramic substrate A, the surface conductor 21 of the multilayer ceramic substrate body 20 and the terminal electrode 13 of the multilayer ceramic capacitor 11 are electrically connected via the connection conductor 10, and the multilayer ceramic substrate The surface conductor 21 of the main body 20 and the connection conductor 10 are fixed by sintering, and the terminal electrode 13 of the multilayer ceramic capacitor 11 and the connection conductor 10 are also fixed by sintering.
That is, in this multilayer ceramic substrate A, the multilayer ceramic capacitor 11 which is a chip-type electronic component is mounted on the multilayer ceramic substrate body 20 by a fixing force by sintering without using solder, and is laminated with the surface conductor 21. The terminal electrode 13 of the ceramic capacitor 11 is electrically connected via the connecting conductor 10.

Next, a method for manufacturing the multilayer ceramic substrate A will be described.
(1) Preparation of base material layer containing ceramic powder and glass material In forming the base material layer constituting the main part of the multilayer ceramic substrate main body, first, mixed powder obtained by mixing ceramic powder and glass material An appropriate amount of each of a binder, a dispersant, a plasticizer, an organic solvent, and the like are added and mixed to prepare a ceramic slurry.
Various ceramic powders can be used, and an example of a preferable material is alumina (Al ₂ O ₃ ) powder.

  The glass material may be contained as glass powder from the beginning, or may precipitate glassy material in the firing step. Further, such a glass material may be crystallized by depositing a crystalline substance at least in the final stage of the firing process. As the glass material, for example, a borosilicate glass-based glass powder capable of precipitating a crystalline material with low dielectric loss such as forsterite, akermanite or diopsite can be advantageously used.

Next, the ceramic slurry is formed into a sheet shape by a method such as a doctor blade method to produce a green sheet for a base material layer (ceramic green sheet for a substrate).
Incidentally, more specifically, as a glass powder, CaO: L0～55 wt%, SiO _2: 45 to 70 wt%, Al ₂ O _3: 0 to 30 wt%, impurities: 0-10 wt%, B ₂ O ₃ : 50 to 64% by weight of glass powder (average particle size 1.5 μm) having a composition of 5 to 20% by weight, and 35% of Al ₂ O ₃ powder (average particle size 1.0 μm) as ceramic powder ~ 50 wt% is mixed, this mixture is dispersed in an organic vehicle composed of an organic solvent, a plasticizer, etc. to prepare a slurry, and this slurry is formed into a sheet by a doctor grade method or a casting method, A ceramic green sheet for a substrate is produced. The Al ₂ O ₃ powder as the ceramic powder may contain 0 to 10% by weight of impurities.

  The substrate (base material layer) is usually formed by laminating a plurality of ceramic green sheets, but may be composed of a single ceramic green sheet. The ceramic green sheet for a substrate is preferably a ceramic green sheet formed by the above-described sheet forming method, but may be an unsintered thick film printed layer formed by a thick film printing method. In addition to the insulator material described above, a magnetic material such as ferrite and a dielectric material such as barium titanate can also be used for the ceramic powder.

Moreover, as the ceramic green sheet for substrates, it is preferable to use a low-temperature sintered ceramic green sheet that is sintered at a temperature of 1050 ° C. or lower. And for that purpose, it is desirable to use what has a softening point of 750 degrees C or less as the glass powder mentioned above.
In Example 1, as a ceramic green sheet for a substrate, a low-temperature sintered ceramic green sheet having a main component of an alumina-based ceramic powder and a borosilicate glass-based glass powder and a thickness after firing of 50 μm is used. It was.

(2) Preparation of constraining layer As a constraining layer used in the method for producing a ceramic molded body of the present invention,
(a) Until the low-temperature sintered ceramic material constituting the base material layer is sintered, that is, in the first firing step of firing in a low oxygen atmosphere, the original function of the constraining layer that suppresses the shrinkage of the base material layer is achieved. Indeed,
(b) It is necessary to have the following two properties of burning out in the second baking step in which baking is performed under a higher oxygen partial pressure than in the first baking step. For this reason, a constraining layer containing as a main component a burning material that does not burn out when fired in a low oxygen atmosphere but burns down when fired at a high oxygen partial pressure is used.

  And as a preferable constrained layer, the constrained layer which uses carbon powder as a burning material can be used, for example.

  In addition, the burned-out material such as carbon powder can constitute a constrained layer having such a property that the constraining layer containing it as a main component can exert a sufficient restraining force, that is, a constraining layer that is unlikely to shrink in the first firing step. It is desirable that

Moreover, it is desirable that the burned-out material constituting the constraining layer has a combustion temperature that is somewhat high so that the burned-out material does not burn in the first firing step. By using a material having a high combustion temperature as the burned-out material, it is possible to increase the heating temperature in the binder removal step, to reliably perform the binder removal, and to expand the range of binder selection.
Moreover, as a burning material, it is desirable that the combustion temperature is 600 degreeC or more, for example.

  In order to exert a sufficient restraining force on the constraining layer, it is preferable that the glass material contained in the base material layer surely permeates the constraining layer to form the permeation layer. For this purpose, it is desirable to dispose the constraining layer in close contact with the base material layer so that the glass material of the base material layer surely penetrates into the constraining layer. For example, when forming a constraining layer by laminating sheets for constraining layers, it is desirable to pressure-bond the sheet to the base material layer. When forming a constraining layer by applying a paste, a printing jig is used. It is desirable to apply the paste in a state in which it is pressed and adhered to the base material layer.

  Further, when carbon powder is used as the burned material, it is desirable that the particle size is in the range of 0.1 to 100 μm. When the particle size is 100 μm or less, a large restraining force can be obtained. In the case of 0.1 μm or more, it is easy to burn out in the second firing step.

  In addition, the constraining layer needs to be burned and burned out by introducing air in the second baking step after the first baking step and baking in an atmosphere having a high oxygen partial pressure. In order to make it easy to burn out in the firing step, it is preferable that the constraining layer is formed from, for example, carbon powder, a binder, and a solvent, and other additives are reduced.

  Moreover, it is preferable that the thickness of the constrained layer 31 is 100 μm to 200 μm. This is because when the thickness is 100 μm or more, it can be made to function as a constraining layer by one layer, and when it is 200 μm or less, sheet molding can be facilitated.

  In Example 1, a constraining layer 31 (FIG. 2) is prepared using a paste mainly composed of carbon powder having an average particle diameter of about 3 μm, and a through hole for constraining via holes (restraint) is formed at a predetermined position. Layer through-holes) 33 (FIG. 2), and the constraining layer through-holes 33 are filled with a conductive paste containing Ag—Pd powder as a conductive component, and fired at a predetermined position as shown in FIG. A constraining layer 31 including a connection conductor via-hole conductor 10a that later becomes the connection conductor 10 (FIG. 1) was produced.

(3) Chip Type Electronic Component In Example 1, the multilayer ceramic capacitor 11 (see FIG. 1) was used as the chip type electronic component mounted on the surface of the multilayer ceramic substrate. This multilayer ceramic capacitor 11 is obtained through a firing process at 950 ° C., and has an internal electrode made of an Ag—Pd alloy, and has terminal electrodes 13 that are electrically connected to predetermined internal electrodes at both ends. It is.

(4) Fabrication of laminate
(a) The low-temperature sintered ceramic green sheet (ceramic green sheet for substrate) 1a (FIG. 2) produced mainly as described above and mainly composed of ceramic powder and glass material is added to the via-hole conductor 23 as necessary. The substrate ceramic provided with the unsintered via-hole conductor 23a (FIG. 2) is provided by forming a through-hole 12 (FIG. 2) for forming the substrate and filling the through-hole 12 with a conductive paste or conductive powder. Green sheet 1a was formed. In Example 1, the through-hole 12 was filled with a conductive paste containing an Ag—Pd alloy as a conductive component.

  (b) The unsintered outer conductor 21a and the inner conductor 22a (FIG. 2) were formed on the ceramic green sheet 1a for a substrate, for example, by printing a silver-based conductive paste as necessary. .

  Next, as shown in FIG. 2, a constraining layer 31 that does not include a via hole conductor for connection conductors, and a plurality of substrate ceramic green sheets 1 a, a constraining layer 31 that includes a via hole conductor 10 a for connection conductors at predetermined positions. Stack and press in this order. Thus, an unfired laminate 32 having a structure in which constraining layers 31 are disposed on both upper and lower sides of a base material layer (unfired multilayer ceramic substrate) 20a as shown in FIG. 2 is produced.

(5) Mounting of chip-type electronic component Then, an organic spray adhesive is applied to a region of the unfired laminate 32 including the exposed surface (upper surface) of the connection conductor via-hole conductor 10a of the constraining layer 31 on the upper surface side. A multilayer ceramic capacitor 11 was mounted as a chip-type electronic component (see FIG. 3).

(6) Binder removal and firing Then, the unfired laminated body 32 on which the multilayer ceramic capacitor 11 is mounted is heated from room temperature to 400 ° C. at a heating rate of 1 ° C./min in the air and held for 1 hour. The binder was removed.
Thereafter, nitrogen is introduced and the oxygen partial pressure is 10 ⁻⁵ atm, that is, the low-temperature sintered ceramic material contained in the substrate ceramic green sheet 1a constituting the base layer (unfired multilayer ceramic substrate body) 20a is Although sintered, the burned-out material constituting the constraining layer 31 is not burned out, and in a low oxygen atmosphere such that the constraining layer 31 functions to suppress shrinkage in the planar direction of the base material layer (multilayer ceramic substrate) 20. The temperature was raised from 400 ° C. to 870 ° C. at a rate of 1 ° C./min, and held at 870 ° C. for 10 minutes (first firing step).
Then, the atmosphere is introduced, and under the condition of atmospheric pressure and oxygen partial pressure of 0.21 atm, that is, the oxygen partial pressure is higher than that in the first firing step, and the burned-out material constituting the constrained layer 31 is burned out. Holding for 10 minutes (second firing step), the constraining layer 31 was burned away.
Thereby, a ceramic electronic component (multilayer ceramic substrate) A having a structure as shown in FIG. 1 is obtained.

The binder removal step prior to the firing step can be usually performed by raising the temperature from room temperature to the decomposition or combustion temperature of the binder in the atmosphere and holding it for a certain period of time.
For example, the binder can be removed by raising the temperature from room temperature to 400 ° C. in the air and holding it for 60 minutes.

  In the method for manufacturing a ceramic electronic component of the present invention, it is desirable to perform the binder removal step in an atmosphere having a high oxygen partial pressure, such as the air, in order to obtain high efficiency. However, it is possible to remove the binder even under a condition where the oxygen partial pressure is lower than that in the atmosphere, and in some cases, it is also possible to carry out in a low oxygen atmosphere where the oxygen partial pressure is considerably lower than that in the atmosphere.

Regarding the conditions in the firing step, in the first firing step, for example, it is desirable to introduce nitrogen after the binder removal step to form a low oxygen atmosphere. In the present invention, the low oxygen atmosphere in the first firing step refers to an atmosphere having an oxygen partial pressure lower than that of the air. Particularly when the oxygen partial pressure is 10 ⁻³ to 10 ⁻⁶ atm, the constrained layer is burned out. This is preferable because the base material layer can be surely restrained without doing so.
In the second baking step after the completion of the first baking step, it is desirable to perform baking by introducing air. For example, the constraining layer can be efficiently burned off by firing for about 10 minutes under the conditions of temperature to room temperature in the first firing step.

  In addition, although a 1st baking process and a 2nd baking process may be implemented at a different baking temperature, it is also possible to make the baking temperature in each baking process the same. In addition, the first firing step and the second firing step may be performed continuously, or after the first firing step is performed, the first firing step is once taken out of the furnace and again put into the furnace to perform the second firing step. Also good.

  As described above, according to the method of the first embodiment, the multilayer ceramic capacitor (chip-type electronic component) 11 is formed on the multilayer ceramic substrate body (ceramic molded body) 20 without requiring a soldering process such as reflow. The multilayer ceramic substrate A having the mounted structure can be efficiently manufactured.

  Further, in the multilayer ceramic substrate A of Example 1, the surface conductor 21 and the connection conductor 10 of the multilayer ceramic substrate body 20 and the terminal electrode 13 and the connection conductor 10 of the multilayer ceramic capacitor 11 are fixed by sintering. Since it has a structure and the multilayer ceramic capacitor 11 is mounted on the multilayer ceramic substrate main body 20 without interposing solder, there is no room for the problem of solder flash.

  In addition, since firing is performed with the constraining layer 31 interposed between the base material layer (multilayer ceramic substrate body) 20a and the multilayer ceramic capacitor 11 which is a chip-type electronic component, in the first firing step In addition, the shrinkage in the planar direction of the base material layer (multilayer ceramic substrate body) 20a is suppressed, and the influence of the shrinkage of the base material layer 20 is not directly transmitted to the multilayer ceramic capacitor 11, so the multilayer ceramic substrate body 20 and the multilayer ceramic capacitor 11 can be prevented from cracking.

  Further, since the firing is performed in a state where the multilayer ceramic capacitor 11 is not in direct contact with the multilayer ceramic substrate body 20, the influence of the difference in thermal expansion coefficient is small. The risk of cracking can be reduced.

  Furthermore, since the burnt-out material constituting the constrained layer 31 is burned out by firing in the second firing step under conditions of higher oxygen partial pressure than the first firing step, a conventional constrained layer made of a material that does not burn out is used. As in the case of performing constrained firing, there is no need to remove the constraining layer by physical or mechanical treatment such as wet blasting after the firing step, and the manufacturing process can be simplified. In addition, as in the case of constrained firing using the conventional constraining layer, it is possible to prevent the fired body from being cracked or chipped in the step of removing the constraining layer.

In addition, since the constraining layer is burned out, the constraining layer does not remain between the multilayer ceramic capacitor 11 that is the chip-type electronic component and the multilayer ceramic substrate body 20, and it is possible to prevent inconveniences from occurring. it can.
Therefore, according to the present invention, a ceramic electronic component with high dimensional accuracy can be manufactured with a high yield without requiring a complicated manufacturing process.

FIG. 4 is a cross-sectional view showing another ceramic electronic component (multilayer ceramic substrate B) manufactured by the method for manufacturing a ceramic electronic component of the present invention, and FIGS. 5 to 8 are views showing the manufacturing method.
4 to 8, the parts denoted by the same reference numerals as those in FIGS. 1 to 3 indicate the same or corresponding parts.

In this multilayer ceramic substrate B, a recess 40 is formed on the surface of the multilayer ceramic substrate body 20 that is a ceramic molded body, and the multilayer ceramic capacitor 11 that is a chip-type electronic component is disposed in the recess 40.
More specifically, in this ceramic electronic component B, the surface conductor 21 connected to the region where the multilayer ceramic capacitor 11 is mounted on the upper surface of the multilayer ceramic substrate body 20, that is, the terminal electrode 13 of the multilayer ceramic capacitor 11 is disposed. The recess 40 is formed in a region including at least a part of the formed region, and the surface conductor 21 and the terminal electrode 13 of the multilayer ceramic capacitor 11, each of which is located in the recess 40 of the multilayer ceramic substrate body 20, It is electrically connected via the connection conductor 10.

  The surface conductor 21 and the connection conductor 10 of the multilayer ceramic substrate body 20 are fixed by sintering, and the terminal electrode 13 and the connection conductor 10 of the multilayer ceramic capacitor 11 are also fixed by sintering.

  In FIG. 4, although the illustration of the internal configuration of the multilayer ceramic substrate body 20 is omitted, the configuration is the same as that of the first embodiment, and the configuration of other parts is also described above. This is the same as in the first embodiment.

  When the concave portion 40 is formed on the surface of the multilayer ceramic substrate main body 20 as in the multilayer ceramic substrate B of the second embodiment, and the multilayer ceramic capacitor 11 is disposed in the concave portion 40, the multilayer of the first embodiment. In addition to the effect obtained in the case of the ceramic substrate A, when the height of the connection conductor 10 is the same, it is possible to reduce the height of the entire product by the depth of the recess 40.

Next, a method for manufacturing the multilayer ceramic capacitor of Example 2 will be described.
A constraining layer 31 that does not include a via-hole conductor for connecting conductors, and a plurality of ceramic green sheets 1a for substrates that are the same as those used in Example 1 above, and a constraining layer 31 that includes a via-hole conductor for connecting conductors 10a at predetermined positions. Stack and press in this order. Thus, an unfired laminate 32 having a structure in which constraining layers 31 are disposed on both upper and lower sides of a base material layer (unfired multilayer ceramic substrate) 20a as shown in FIG. 5 is produced.

  Then, as shown in FIG. 6, pressing is performed using a mold 15 having convex portions 16 having substantially the same dimensions as the multilayer ceramic capacitor 11 to be mounted, and on the surface of the unfired multilayer body 32, as shown in FIG. 7. Then, the concave portion 40 having a size and shape substantially corresponding to the multilayer ceramic capacitor 11 is formed. The recess 40 is formed over both the upper constraining layer 31 and the base material layer (unfired multilayer ceramic substrate) 20a in contact with the lower surface of the constraining layer 31.

  Next, as shown in FIG. 8, a multilayer ceramic capacitor was mounted on the bottom surface of the recess 40 of the constraining layer 31 on the upper surface side. At that time, after applying an organic spray adhesive to the region including the exposed surface of the via hole conductor 10a for the connection conductor, the multilayer ceramic capacitor 11 is connected to the recess 40, and the terminal electrode 13 is connected to the via hole conductor 10a for the connection conductor. Fixed to.

Then, after the unsintered laminated body 32 mounted with the multilayer ceramic capacitor 11 was heated from room temperature to 400 ° C. at a heating rate of 1 ° C./min in the atmosphere and held for 1 hour to perform binder removal. The low-temperature sintered ceramic material contained in the substrate ceramic green sheet 1a constituting the base material layer (unfired multilayer ceramic substrate body) 20 is fired by introducing nitrogen into an oxygen partial pressure of 10 ⁻⁵ atm. However, the burnout material constituting the constraining layer 31 does not burn out, and the constraining layer 31 functions from 400 ° C. to 870 ° C. in a low oxygen atmosphere that functions to suppress shrinkage in the planar direction of the multilayer ceramic substrate 20. Was heated at a heating rate of 1 ° C./min and held at 870 ° C. for 10 minutes (first firing step).

Thereafter, air is introduced, under the condition of oxygen partial pressure of 0.21 atm under normal pressure, that is, in an atmosphere where the oxygen partial pressure is higher than that in the first firing step and the burned-out material constituting the constrained layer 31 is burned out. Holding for 10 minutes (second firing step), the constraining layer 31 was burned away.
Thereby, a ceramic electronic component (multilayer ceramic substrate) B having a structure as shown in FIG. 4 can be obtained.

  As described above, the multilayer ceramic substrate B of the second embodiment has a structure in which the multilayer ceramic capacitor 11 is disposed in the concave portion 40 on the surface of the multilayer ceramic substrate body 20, and therefore the multilayer ceramic substrate of the first embodiment. In addition to the effect obtained in the case of the ceramic substrate A, when the height of the connection conductor 10 is the same, an effect that the overall height of the product can be reduced by the depth of the recess 40 is obtained.

  In Example 2, pressing is performed using the mold 15 having the projections 16 having substantially the same dimensions as the multilayer ceramic capacitor 11 to be mounted, so that the recesses 40 are formed on the upper constraining layer 31 and the constraining layer 31. Although it is formed over both of the base material layer (unfired multilayer ceramic substrate) 20a in contact with the lower surface, by adjusting the height and pressing force of the convex portion 16 of the mold 15, as shown in FIG. It is also possible to form the recess 40 only in the constraining layer 31.

When the concave portion 40 is formed only in the constraining layer 31, the dimension in the height direction of the connection conductor is reduced corresponding to the depth of the concave portion 40, and the entire product is corresponding to the depth of the concave portion 40. Low profile can be achieved.
In the first and second embodiments, the multilayer ceramic capacitor 11 is mounted after the organic spray adhesive is applied to the region including the exposed surface of the connection conductor via-hole conductor 10a. Will be used for the firing process in a state that is securely held at a predetermined position. Therefore, it is possible to ensure the mounting position accuracy of the multilayer ceramic capacitor. In addition, since the organic spray adhesive is burned off in the firing step, there is no problem in electrical connection between the fired chip-type electronic component and the multilayer ceramic substrate.
In addition, although the spray type thing is used as an organic type adhesive agent, the thing of the type to apply, for example other than a spray type can also be used.

  In the first and second embodiments, the case where the ceramic electronic component is a multilayer ceramic substrate and the chip-type electronic component is a multilayer ceramic capacitor has been described as an example. However, the present invention is not limited to this, and the LC composite unit electronic The present invention can be applied to various ceramic electronic components such as components and ceramic filters, and chip electronic components are not limited to multilayer ceramic capacitors, and are various chip electronic components such as chip multilayer coil components and chip resistors. It is possible to apply to cases.

  The present invention is not limited to the above-described examples in other points as well. Specific types and blending ratios of the ceramic powder and glass material constituting the base material layer, and the burned-out material constituting the constrained layer. With respect to specific types, specific conditions in the first and second firing steps, processing conditions in the binder removal step, and the like, various applications and modifications can be made within the scope of the invention.

As described above, according to the present invention, it is possible to efficiently and surely mount chip-type electronic components without requiring a mounting process using a bonding material such as solder or conductive adhesive, It becomes possible to efficiently manufacture a ceramic electronic component on which a chip-type electronic component is mounted.
Therefore, the present invention can be widely used for various ceramic electronic components that have a structure in which chip-type electronic components are mounted and are manufactured through a firing process.

Claims (9)

A base material layer comprising a surface conductor and containing ceramic powder and a glass material;
It is disposed so as to be in contact with at least one main surface of the base material layer and is not burned down when fired in a low oxygen atmosphere, but is burned down when fired at a higher oxygen partial pressure than the low oxygen atmosphere. A constraining layer comprising a via-hole conductor connected to the surface conductor;
A laminate production step of producing an unfired laminate comprising:
A chip-type electronic component mounting step for mounting the chip-type electronic component on the constraining layer so that the terminal electrode thereof is in contact with the via-hole conductor;
The surface conductor and the via-hole conductor of the base material layer, and the terminal electrode and the via-hole conductor of the chip-type electronic component are fixed by sintering, respectively, and the surface conductor and the terminal electrode are interposed via the via-hole conductor. And a firing step of firing the unfired laminate so as to be in an electrically connected state,
The firing step includes
A first firing step of firing the unfired laminate in the low-oxygen atmosphere and sintering the base material layer without burning out the burned material constituting the constraining layer;
A method for producing a ceramic electronic component, comprising: a second firing step in which firing is performed under a condition in which an oxygen partial pressure is higher than that in the first firing step, and the burnt material constituting the constraining layer is burned off.   2. The ceramic according to claim 1, wherein, in the laminate manufacturing step, a recess is formed in a region on the surface of the constraining layer where the chip electronic component is mounted and the via hole conductor is included. Manufacturing method of electronic components.   3. The method of manufacturing a ceramic electronic component according to claim 2, wherein a recess is also formed in a region of the surface of the base material layer that is in contact with a back surface side of the region where the recess of the constraining layer is formed.   In the laminate manufacturing step, the concave portion is formed by pressure-bonding a mold having a convex portion having a size corresponding to the chip-type electronic component from the upper surface side of the constraining layer. A method for producing a ceramic electronic component according to any one of 2 and 3.   The ceramic electronic component according to claim 1, wherein in the first firing step, firing is performed so that the glass material contained in the base material layer penetrates into the constraining layer. Production method.   The method for producing a ceramic electronic component according to claim 1, wherein the burned-out material is carbon powder. The base material layer includes a binder, and
A binder removal step of removing the binder contained in the base material layer before the first firing step in the firing step;
The method for manufacturing a ceramic electronic component according to claim 1, wherein the binder removal step is performed in an oxygen-containing atmosphere and at a temperature at which the burnout material does not burn out.   In the laminate manufacturing step, the constraining layer is formed by arranging a sheet containing the burned-out material as a main component so as to be in contact with at least one main surface of the base material layer, The manufacturing method of the ceramic electronic component in any one of Claims 1-7.   In the laminate manufacturing step, the constraining layer is formed by applying a paste containing the burned-out material as a main component to at least one main surface of the base material layer. The manufacturing method of the ceramic electronic component in any one of -8.

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