JP2021182595A - Method for manufacturing electronic component - Google Patents

Abstract

To provide a method for manufacturing an electronic component, capable of easily manufacturing an electronic component without causing poor connection and poor short circuit.SOLUTION: A method for manufacturing an electronic component comprises: carrying an element main body 4 on a first foam sheet 20 so as to contact one of a pair of non-exposure outer surfaces 5c of the element main body 4 positioned on the side opposite to each other without exposing a part of a conductor positioned in the inside of the element main body 4 to the first foam sheet 20; and rolling the element main body 4 on the first foam sheet 20 to hold the element main body 4 on the first foam sheet 20 so as to contact the other exposure outer surface 5b on which a part of the conductor is exposed.SELECTED DRAWING: Figure 5B

Description

The present invention relates to a method of manufacturing an electronic component such as a monolithic ceramic capacitor.

For example, in the process of manufacturing an electronic component such as a monolithic ceramic capacitor, there is a step of forming a terminal electrode on the outer surface of the element body. In order to form a terminal electrode on the outer surface of the element body, for example, as shown in Patent Document 1, a method of forming a terminal electrode using a foamed sheet has been proposed. In the method shown in Patent Document 1, the exposed surface of the internal conductor of the element body is attached to the surface of the foam sheet by using a vibrating alignment jig.

In the method shown in Patent Document 1, when the exposed surface of the inner conductor is formed at the end portion in the longitudinal direction of the element body, the exposed surface of the inner conductor of the element body is formed into a foam sheet by using an alignment jig. It is possible to attach it to the surface of the. However, this method requires a jig that matches the dimensions of the chip (element body), and is inefficient because the yield is poor in order to selectively insert the chip into the hole of the alignment jig. Also, it is difficult to selectively determine the orientation of the chip. As a result, it is difficult to attach a specific wide outer surface inside the outer surface of the element body to the surface of the foamed sheet to form a terminal electrode or the like. This is because it is difficult to selectively insert the wide outer surface of the outer surface of the element body into the hole of the alignment jig.

Recently, the end portion of the internal electrode layer may be exposed on the outer surface of the element body before the terminal electrode is formed, and a side gap ceramic film or a side gap glass film may be formed on the outer surface thereof. This is because the pattern shift of the internal electrode layer is prevented and the area of the internal electrode layer is secured. When the method shown in Patent Document 1 is to be adopted in order to form the ceramic film or the glass film on the outer surface for the side gap of the element body in this way, the vibration of the alignment jig causes the inner conductor of the element body to be formed. Impact may be applied to the exposed surface. If an impact is applied to the exposed surface of the internal conductor of the element body, conductor dust or the like may be generated, which may cause short-circuit failure or insulation failure.

Japanese Unexamined Patent Publication No. 6-260377

The present invention has been made in view of such an actual situation, and an object of the present invention is to provide a method for manufacturing an electronic component, which can easily manufacture an electronic component without causing a connection failure, a short circuit failure, or the like. be.

In order to achieve the above object, the method for manufacturing an electronic component according to the first aspect of the present invention is:
The element body is such that one of the pair of unexposed outer surfaces located on opposite sides of the element body is in contact with the first foam sheet so that a part of the conductor located inside the element body is not exposed. In the process of transporting the above first foam sheet onto the first foam sheet,
A step of rolling the element body on the first foam sheet and holding the element body on the first foam sheet so that the exposed outer surface of one of the exposed conductors comes into contact with the element body.
A step of forming the other functional portion on the other exposed outer surface of the element body held by the first foam sheet, and a step of forming the other functional portion.
A step of drying the other functional part at a temperature lower than the foaming temperature of the first foamed sheet, and
A step of heating the first foamed sheet at a temperature equal to or higher than the foaming temperature of the first foamed sheet to transfer the element main body on which the other functional portion is formed to a transfer member.
The present invention comprises a step of forming one of the functional portions on the exposed outer surface of one of the element main bodies transferred to the transfer member.

In the method for manufacturing an electronic component of the present invention, the element body is placed on the first foam sheet so that one of the main surfaces (non-exposed outer surface of the inner conductor, which is not the exposed surface) is in contact with the first foam sheet. Transport. Therefore, the exposed surface of the internal conductor formed on the exposed outer surface other than the main surface of the element main body is not damaged by the vibrating transport portion. As a result, when forming a functional portion in the element body, poor connection or short circuit is unlikely to occur.

Further, in the method of the present invention, the element body is rolled on the first foam sheet so that the element body is brought into contact with one outer surface (exposed outer surface) on which a part of the conductor is exposed. Hold on the first foam sheet. Therefore, the outer surface on which the functional portion is to be formed can be easily positioned on the first foam sheet on the side opposite to the outer surface adhering to the first foam sheet. Further, since the element body is only rolled on the surface of the first foam sheet, there is little damage to the outer surface where a part of the conductor in the element body is exposed. It is also possible to remove dust and the like adhering to the outer surface (exposed outer surface or non-exposed outer surface) of the element body by adhering it to the adhesive surface of the surface of the first foam sheet.

With a large number of element bodies held in the first foam sheet, functional parts such as a paste film can be easily applied to the outer surface on the side opposite to one outer surface (exposed outer surface) held in the first foam sheet of the element body. Can be formed. Further, by drying the functional part at a temperature lower than the foaming temperature of the first foamed sheet, a large number of element bodies are held in the first foamed sheet, and a large number of element bodies are dried at the same time without peeling off from the sheet. Will be possible.

Further, since the functional portion can be transferred by contacting the transfer member having a weak adhesive force, the functional portion is less damaged and the functional portion is less likely to be scratched or defective. Then, by heating at a temperature equal to or higher than the foaming temperature of the first foamed sheet, the element main body can be easily transferred from the first foamed sheet to the transfer member. Further, the element body is held on one outer surface (exposed outer surface) of the element body on which the functional portion is formed by the transfer member, so that the element body is on the outer surface opposite to the outer surface held by the transfer member of the element body. , A functional part such as a paste film can be easily formed.

Examples of the functional unit include terminal electrodes, side gap insulating films (glass film, ceramic film, or resin film). In the method of the present invention, an insulating functional portion such as an insulating film for a side gap is formed on the outer surface of the element body where the conductor is exposed, so that the internal electrode layer formed inside the element body is effective. Moreover, it is possible to effectively prevent short circuits of these internal electrode layers. Further, by forming a conductive functional part such as a terminal electrode on the outer surface of the element body where the conductor is exposed, an internal electrode layer formed inside the element body without causing a connection failure or the like. It is possible to connect the terminal electrodes to the above.

Preferably, the second foamed sheet is arranged on the first foamed sheet so as to sandwich the element main body, and the second foamed sheet is placed on the first foamed sheet at least in the first foamed sheet. The element body is rolled on the first foam sheet by relatively moving along the first axis parallel to the surface.

The surface of the foamed sheet has adhesiveness, and by moving the second foamed sheet relative to the first foamed sheet along a first axis parallel to at least the surface of the first foamed sheet, these The element body can be easily rolled between the sheets. As a result, the exposed outer surface on which the functional portion is to be formed can be easily positioned on the first foamed sheet on the side opposite to the exposed outer surface adhering to the first foamed sheet.

Further, since the element body is only rolled between the first foam sheet and the second foam sheet, there is little damage to the exposed outer surface (exposed outer surface) of the conductor in the element body. Further, it is also possible to remove dust and the like adhering to the outer surface (exposed outer surface or non-exposed outer surface) of the element body by adhering to the adhesive surface of the surface of these foam sheets.

Preferably, the foaming temperature of the second foamed sheet is lower than the foaming temperature of the first foamed sheet.
After rolling the element body on the first foamed sheet, the element body is heated at a temperature lower than the foaming temperature of the first foamed sheet and higher than the foaming temperature of the second foamed sheet, and the second foamed sheet is heated to the element. Pull it away from the main body.

By heating at a temperature equal to or higher than the foaming temperature of the second foam sheet, the adhesiveness of the surface of the second foam sheet is reduced, and the element body can be easily separated from the second foam sheet without damaging the element body. be able to.

Preferably, the transfer member is a third foamed sheet, and the foaming temperature of the third foamed sheet is higher than the foaming temperature of the first foamed sheet.
When the element body is transferred from the first foamed sheet to the third foamed sheet, the first foamed sheet is at a temperature lower than the foaming temperature of the third foamed sheet and higher than the foaming temperature of the first foamed sheet. The sheet is heated to transfer the element body from the first foam sheet to the third foam sheet.

By heating the first foamed sheet at a temperature higher than the foaming temperature of the first foamed sheet, the adhesive strength of the adhesive surface on the surface of the first foamed sheet is reduced, and the adhesive surface on the surface of the third foamed sheet is reduced. The element body can be easily transferred. Further, since the adhesive strength of the adhesive surface of the surface of the first foamed sheet is reduced, the adhesive force can be transferred to the surface of the third foamed sheet without damaging the element body.

The method for manufacturing an electronic component according to the second aspect of the present invention is as follows.
A step of holding the element body on the first foam sheet so that one of the exposed outer surfaces on which one of the functional portions is to be formed comes into contact with each other.
A step of forming the other functional portion on the other exposed outer surface of the element body held by the first foam sheet, and a step of forming the other functional portion.
A step of drying the other functional part at a temperature lower than the foaming temperature of the first foamed sheet, and
A step of rolling the element body on the first foam sheet at least 180 degrees or more to bring the functional portion formed on the element body into contact with the first foam sheet to hold the element body. ,
The present invention includes a step of forming one of the functional portions on the exposed outer surface of one of the element main bodies.

In the method for manufacturing an electronic component according to the second aspect of the present invention, the element body is rolled on the first foam sheet without using a transfer member or the like, so that the element body functions on a pair of exposed outer surfaces facing each other. The part can be formed. Since there is no need to transfer, a sheet having a high foaming temperature can be used as the first foaming sheet, and as a result, the drying temperature of the functional portion can also be increased. The drying temperature can be increased below the foaming temperature of the first foamed sheet. In addition, since no transfer member is required, it also contributes to a reduction in the number of parts for manufacturing.

Further, the element body can be inverted by simply rolling the element body on a relatively soft foam sheet without the need for a transfer member, and when the element body is inverted, damage to the element body is caused. few. Therefore, when forming a functional portion on the element body, poor connection or short circuit is unlikely to occur.

Preferably, one of the other pair of unexposed outer surfaces located on opposite sides of the element body, in which a part of the conductor located inside the element body is not exposed, comes into contact with the first foam sheet. After transporting the element body onto the first foam sheet,
The element body is rolled on the first foam sheet, and the element body is held by the first foam sheet so that the exposed outer surface of one of the exposed conductors comes into contact with the element body.
After that, the other functional portion is formed on the other exposed outer surface of the element body.

Also in this method, the element body is conveyed onto the first foam sheet so that one of the main surfaces (non-exposed outer surface of the inner conductor, which is not the exposed surface) of the element body comes into contact with the first foam sheet. Therefore, the exposed surface of the internal conductor formed on the outer surface other than the main surface of the element main body is not damaged by the vibrating transport portion. Therefore, when the functional portion is formed on the element main body, poor connection or short circuit is unlikely to occur.

The element body may be a green laminate (including a green chip) before firing, but is preferably a ceramic chip after firing. It is easy to form a functional part on the ceramic chip after firing.

FIG. 1 is a schematic cross-sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention. FIG. 2A is a cross-sectional view taken along the line IIA-IIA shown in FIG. FIG. 2B is a cross-sectional view taken along the line IIB-IIB shown in FIG. FIG. 3A is a schematic cross-sectional view parallel to the X-axis and the Z-axis showing the green sheet laminating process in the manufacturing process of the monolithic ceramic capacitor shown in FIG. FIG. 3B is a schematic cross-sectional view parallel to the Y-axis and the Z-axis showing the process of laminating the green sheet shown in FIG. 3A. 4A is a schematic perspective view of the element main body after the cutting step after the laminating step shown in FIGS. 3A and 3B. FIG. 4B is a schematic perspective view of the element body after the cutting step according to the method for manufacturing a monolithic ceramic capacitor according to another embodiment of the present invention. FIG. 5A is a schematic perspective view showing a process of rolling the element main body shown in FIG. 4A. FIG. 5B is a schematic perspective view showing the continuation of the process shown in FIG. 5A. FIG. 5C is a schematic perspective view showing the continuation of the process shown in FIG. 5B. FIG. 6A is a schematic perspective view showing the continuation of the process shown in FIG. 5C. FIG. 6B is a schematic perspective view showing the continuation of the process shown in FIG. 6A. FIG. 6C is a schematic perspective view showing the continuation of the process shown in FIG. 6B. FIG. 7A is a schematic perspective view showing the continuation of the process shown in FIG. 6C. FIG. 7B is a schematic perspective view showing the continuation of the process shown in FIG. 7A. FIG. 7C is a schematic perspective view showing the continuation of the process shown in FIG. 7B. FIG. 7D is a schematic perspective view showing the continuation of the process shown in FIG. 7C. FIG. 8A is a schematic perspective view showing a continuation of the process shown in FIG. 7B according to the method for manufacturing a multilayer ceramic capacitor according to another embodiment of the present invention. FIG. 8B is a schematic perspective view showing the continuation of the process shown in FIG. 8A. FIG. 9 is a schematic perspective view showing the continuation of the process shown in FIG. 7D.

Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

First Embodiment First, as an example of an electronic component to which the method for manufacturing an electronic component according to the present embodiment is applied, the overall configuration of a monolithic ceramic capacitor will be described.

(Multilayer ceramic capacitor)
As shown in FIG. 1, the multilayer ceramic capacitor 2 according to the present embodiment includes an element main body 4 made of a ceramic sintered body, a first terminal electrode (a type of functional portion) 6, and a second terminal electrode (of the functional portion). Type) 8 and. In the present embodiment, the element main body 4 has a rectangular parallelepiped shape having six outer surfaces as a whole.

That is, the element main body 4 has a pair of outer surfaces 5a and 5a located on opposite sides of each other along the Y axis as shown in FIG. 1 and opposite sides of each other along the X axis as shown in FIG. 2B. It has a pair of outer surfaces 5b and 5b that are located and a pair of outer surfaces 5c and 5c that are located on opposite sides of each other along the Z axis as shown in FIG. 2A. In the figure, the X-axis, the Y-axis, and the Z-axis are substantially perpendicular to each other.

As shown in FIG. 1, the first terminal electrode 6 is formed so as to cover one outer surface 5a of the element body 4, and the second terminal electrode 8 covers the other outer surface 5a of the element body 4. It has been formed. Further, as shown in FIGS. 2A and 2B, the outer surfaces 5b and 5b located on both sides of the element main body 4 along the X axis have insulating films (functional portions) 16 and so as to cover the outer surfaces 5b and 5b, respectively. 16 are formed respectively.

As shown in FIG. 2B, both ends of the first terminal electrode 6 and the second terminal electrode 8 in the X-axis direction are formed so as to cover both ends of the insulating films 16 and 16 in the Y-axis direction. However, the end edges of the first terminal electrode 6 and the second terminal electrode 8 are separated from each other by a predetermined distance in the Y-axis direction on the insulating film 16, and insulation is ensured.

As shown in FIG. 1, the element body 4 has an inner dielectric layer 10 and an inner electrode layer 12 substantially parallel to a plane including the X-axis and the Y-axis, and is inside between the inner dielectric layers 10. The electrode layers 12 are alternately laminated along the direction of the Z axis. Here, "substantially parallel" means that most of the parts are parallel, but may have some parts that are not parallel, and the internal electrode layer 12 and the inner dielectric layer 10 are somewhat parallel. The idea is that it may be uneven or tilted.

The portion where the inner dielectric layer 10 and the inner electrode layer 12 are alternately laminated is the interior region 13. Further, the element main body 4 has exterior regions 11 on both end faces in the stacking direction Z (Z axis). The exterior region 11 is formed by laminating a plurality of outer dielectric layers. In the following, the "inner dielectric layer 10" and the "outer dielectric layer" may be collectively referred to as a "dielectric layer".

The materials of the dielectric layers constituting the inner dielectric layer 10 and the outer region 11 may be the same or different, and are not particularly limited. For example, a dielectric material having a perovskite structure such as _{ABO 3 or an alkaline niobate ceramic.} Is the main component. In ABO ₃ , A is at least one kind such as Ca, Ba, Sr, and B is at least one kind such as Ti, Zr. The molar ratio of A / B is not particularly limited and is 0.980 to 1.020.

In addition, examples of the auxiliary components contained in the dielectric layer include, but are not limited to, alkali metal compounds such as silicon dioxide, aluminum oxide, and magnesium oxide, manganese oxide, rare earth element oxides, and vanadium oxide. The content may be appropriately determined according to the composition and the like.

By using silicon dioxide and aluminum oxide as sub-ingredients, the firing temperature can be lowered. Further, by using an alkali metal compound such as magnesium oxide, manganese oxide, a rare earth element oxide, vanadium oxide or the like as a sub-component, the life can be improved. The number of layers of the inner dielectric layer 10 and the outer dielectric layer may be appropriately determined according to the intended use and the like.

One of the alternately laminated internal electrode layers 12 is a drawer portion 12α electrically connected to the inside of the first terminal electrode 6 formed on one outer surface 5a in the Y-axis direction of the element body 4. Have. Further, the other internal electrode layer 12 that is alternately laminated is a drawer that is electrically connected to the inside of the second terminal electrode 8 formed on the other outer surface 5a in the Y-axis direction of the element main body 4. It has a portion 12β.

The interior region 13 has a capacity region 14 and drawer regions 15A and 15B. The capacitance region 14 is a region in which the internal electrode layer 12 is laminated with the inner dielectric layer 10 interposed therebetween along the stacking direction. The extraction region 15A is a region located between the extraction portions 12α of the internal electrode layer 12 connected to the terminal electrode 6. The extraction region 15B is a region located between the extraction portions 12β of the internal electrode layer 12 connected to the terminal electrode 8.

The conductive material contained in the internal electrode layer 12 is not particularly limited, and metals such as Ni, Cu, Ag, Pd, Al, and Pt, or alloys thereof can be used. As the Ni alloy, an alloy of one or more elements selected from Mn, Cr, Co and Al and Ni is preferable, and the Ni content in the alloy is preferably 95% by weight or more. The Ni or Ni alloy may contain various trace components such as P in an amount of about 0.1% by weight or less.

The internal electrode layer 12 may be formed by using a commercially available electrode paste, and the thickness of the internal electrode layer 12 may be appropriately determined according to the intended use and the like. As shown in FIG. 2A, the outer surfaces 5b and 5b located at both ends of the element main body 4 in the X-axis direction are provided with insulating films 16 and 16, respectively. Although not shown, the insulating films 16 may also be provided on the outer surfaces 5c and 5c located at both ends of the element main body 4 in the Z-axis direction.

The insulating film 16 may partially cover the ends of the outer surface 5a located at both ends of the element body 4 in the Y-axis direction in the X-axis direction. However, it is preferable that the insulating film 16 does not cover the connection ends of the extraction portions 12α or 12β of the internal electrode layer 12 exposed on the outer surfaces 5a and 5a located at both ends of the element main body 4 in the Y-axis direction shown in FIG. This is because terminal electrodes 6 and 8 need to be formed on the outer surfaces 5a located at both ends of the element main body 4 in the Y-axis direction and connected to the extraction portions 12α or 12β of the internal electrode layer 12.

The main component of the insulating film 16 of the present embodiment is preferably made of glass containing 25% by weight or more of Si. As a result, peeling of the terminal electrodes 6 and 8 can be suppressed. It is considered that this is because the more Si contained in the glass as the main component of the insulating film 16, the better the plating resistance of the insulating film 16 and the more the deterioration due to plating can be suppressed. The main component of the insulating film 16 of the present embodiment is preferably composed of glass containing 25% by weight to 70% by weight of Si. The insulating film 16 of the present embodiment may contain Mg, Ca, Sr, Ba, Li, Na, K, Ti, Zr, B, P, Zn, Al and the like in addition to Si.

Further, by forming the insulating film 16 with a glass component, the fixing strength is improved. It is considered that this is because a reaction phase is formed at the interface between the glass and the element body 4, and the adhesion between the glass and the element body 4 is superior to that of other insulating substances.

In addition, glass has higher insulation than ceramic. Therefore, as compared with the case where the main component of the insulating film 16 is ceramic, when the main component of the insulating film 16 is made of glass, the short circuit occurrence rate is reduced even if the distance between the terminal electrodes 6 and 8 facing each other is shortened. Can be lowered. Therefore, compared to the case where the insulating film 16 is made of ceramic, when the main component of the insulating film 16 is made of glass, the terminal electrodes 6 and 8 are the Y-axis of the end face of the element body 4 in the X-axis direction. Even if the configuration is such that the directional end portion and the Y-axis direction end portion of the Z-axis direction end face are widely covered, the short circuit occurrence rate can be reduced. This effect is more remarkable when the insulating film 16 is also formed on the outer surface 5c located at the end surface of the element main body 4 in the Z-axis direction.

The softening point of the glass contained in the insulating film 16 of the present embodiment is preferably 600 ° C to 950 ° C. As a result, when the insulating film 16 is baked, it is possible to prevent the growth of ceramic particles in the dielectric layer, and it is possible to suppress deterioration of properties such as reliability. From the above viewpoint, the softening point of the glass contained in the insulating film 16 of the present embodiment is more preferably 600 ° C to 850 ° C.

Components other than the glass contained in the insulating film 16 of the present embodiment is not particularly limited, for example, may comprise a ceramic _{filler, BaTiO 3, CaTiO 3, Al} 2 O 3, CaZrO 3, MgO, ZrO 2, It _{may contain Cr 2} O ₃ , CoO and the like.

By covering the end surface of the element main body 4 with the insulating film 16, not only the insulating property is enhanced, but also the durability and moisture resistance against an environmental load from the outside are increased. Further, since the insulating film 16 covers the end surface of the element main body 4 after firing in the X-axis direction to form a side gap, the width of the side gap is small and a uniform insulating film 16 can be formed. ..

The terminal electrodes 6 and 8 may be formed of a laminated film having an electrode film and a coating layer covering the electrode film, respectively. The coating layer is formed by plating, sputtering, or the like. The electrode film may contain glass containing Si. Other components contained in the electrode film are not particularly limited, and for example, known conductive materials such as Cu, Ni, Ag, Pd, Pt, Au, alloys thereof, and conductive resins can be used. The thicknesses of the terminal electrodes 6 and 8 may be appropriately determined according to the intended use and the like.

In the present embodiment, the shape and size of the element main body 4 may be appropriately determined according to the purpose and application, but the width W0 in the X-axis direction shown in FIG. 2A is 0.1 mm to 1.6 mm, as shown in FIG. It is preferable that the length L0 in the Y-axis direction is 0.2 mm to 3.2 mm, and the height H0 in the Z-axis direction shown in FIG. 2A is 0.1 mm to 1.6 mm. According to the method for manufacturing a multilayer ceramic capacitor of the present embodiment, even if the size of the element main body 4 is small as shown below, cutting chips and dust can be easily removed. That is, the size of the element main body 4 of the present embodiment is such that the width W0 in the X-axis direction is 0.1 mm to 0.5 mm, the length L0 in the Y-axis direction is 0.2 mm to 1.0 mm, and the height in the Z-axis direction. H0 may be 0.1 mm to 0.5 mm.

In the present embodiment, the outer surface 5b, which is the end surface of the element main body 4 in the X-axis direction, or the outer surface 5a, which is the end surface in the Y-axis direction, may be mirror-polished. Further, as shown in FIG. 2A, the end portion of the internal electrode layer 12 sandwiched between the inner dielectric layers 10 adjacent to the stacking direction (Z-axis direction) in the X-axis direction is the end surface of the element body 4 in the X-axis direction (the end surface in the X-axis direction). It may be recessed inward from the outer surface 5b) at a predetermined pull-in distance. The pull-in of the end portion of the internal electrode layer 12 in the X-axis direction is formed, for example, by the difference in the sintering shrinkage rate between the material forming the internal electrode layer 12 and the material forming the inner dielectric layer 10.

In the present embodiment, as shown in FIG. 2A, of the insulating film 16, the insulating film 16 is formed from the end surface (outer surface 5b) of the element body 4 in the X-axis direction along the width direction (X-axis direction) of the element body 4. The section to the outer surface of is the gap part. In the present embodiment, the width Wgap of the gap portion in the X-axis direction is the end surface of the insulating film 16 in the X-axis direction from the end surface of the element body 4 in the X-axis direction along the width direction (X-axis direction) of the element body 4. The width Wgap does not have to be uniform along the Z-axis direction and may vary slightly, although it matches the dimensions up to. The average width Wgap is preferably 1 μm to 30 μm. As a result, the influence of the coefficient of thermal expansion of the insulating film 16 is reduced, and structural defects due to the difference in the coefficient of thermal expansion between the element body 4 and the insulating film 16 can be suppressed. The widths Wgap on both sides of the element body 4 in the X-axis direction may be the same or different from each other.

Further, the average of the above-mentioned width Wgap is extremely small as compared with the width W0 of the element main body 4. In the present embodiment, the width Wgap can be made extremely small as compared with the conventional case, and the pull-in distance of the internal electrode layer 12 is sufficiently small. Therefore, in the present embodiment, it is possible to obtain a monolithic ceramic capacitor 2 having a large capacity while being small in size. The width W0 of the element body 4 corresponds to the width of the inner dielectric layer 10 along the X-axis direction. By setting Wgap within the above range, cracks are less likely to occur, and even if the element main body 4 is made smaller, the decrease in capacitance is small.

The ratio of the thickness td of the inner dielectric layer 10 and the thickness te of the inner electrode layer 12 shown in FIG. 2A is not particularly limited, but td / te is preferably 2 to 0.5. The ratio of the thickness t0 of the exterior region 11 (see FIG. 1) to the height H0 of the element body 4 (see FIG. 2A) is not particularly limited, but t0 / H0 may be 0.01 to 0.1. preferable.

(Manufacturing method of multilayer ceramic capacitors)
Next, a method for manufacturing the monolithic ceramic capacitor 2 as an embodiment of the present invention will be specifically described.

First, the inner green sheet 10a shown in FIG. 3A, which constitutes the inner dielectric layer 10 shown in FIG. 1 after firing, and the outer green sheet 11a shown in FIG. 3A, which constitutes the exterior region 11 shown in FIG. Prepare. In order to form these green sheets 10a and 11a, first, an inner green sheet paste and an outer green sheet paste are prepared, respectively. The inner green sheet paste and the outer green sheet paste are usually composed of an organic solvent-based paste or a water-based paste obtained by kneading a ceramic powder and an organic vehicle.

As the raw material of the ceramic powder, various compounds to be composite oxides and oxides, for example, carbonates, nitrates, hydroxides, organic metal compounds and the like can be appropriately selected and mixed and used. In the present embodiment, the raw material of the ceramic powder is used as a powder having an average particle size of 0.45 μm or less, preferably about 0.05 to 0.3 μm. In order to make the inner green sheet extremely thin, it is desirable to use a powder finer than the thickness of the green sheet.

An organic vehicle is a binder dissolved in an organic solvent. The binder used for the organic vehicle is not particularly limited, and may be appropriately selected from various ordinary binders such as ethyl cellulose and polyvinyl butyral. The organic solvent used is not particularly limited, and may be appropriately selected from various organic solvents such as alcohol, acetone, and toluene.

Further, the green sheet paste may contain additives selected from various dispersants, plasticizers, dielectrics, subcomponent compounds, glass frits, insulators and the like, if necessary. Examples of the plasticizer include phthalates such as dioctyl phthalate and benzyl butyl phthalate, adipic acid, phosphoric acid esters, glycols and the like.

Next, the internal electrode pattern layer 12a shown in FIG. 3A, which constitutes the internal electrode layer 12 shown in FIG. 1 after firing, is formed. Therefore, a paste for the internal electrode layer is prepared. The paste for the internal electrode layer is prepared by kneading the above-mentioned conductive material made of various conductive metals and alloys with the above-mentioned organic vehicle. The metal paste (paste for terminal electrodes) that constitutes the terminal electrodes 6 and 8 shown in FIG. 1 after firing may be prepared in the same manner as the paste for the internal electrode layer described above.

Using the paste for the inner green sheet and the paste for the inner electrode layer prepared above, the inner green sheet 10a and the inner electrode pattern layer 12a were alternately laminated as shown in FIGS. 3A and 3B. Manufacture an internal laminate. Then, after manufacturing the inner laminated body, the outer green sheet 11a is formed by using the paste for the outer green sheet, and the pressure is applied in the laminating direction to obtain the green laminated body.

In addition to the above, as a method for manufacturing a green laminate, a predetermined number of inner green sheets 10a and internal electrode pattern layers 12a are alternately laminated directly on the outer green sheet 11a and pressed in the lamination direction to form a green laminate. May be obtained.

Specifically, first, the inner green sheet 10a is formed on a carrier sheet (for example, PET film) as a support by a doctor blade method or the like. The inner green sheet 10a is formed on the carrier sheet and then dried. Next, the inner electrode pattern layer 12a is formed on the surface of the inner green sheet 10a by using the paste for the inner electrode layer, and the inner green sheet 10a having the inner electrode pattern layer 12a is obtained. After laminating the inner green sheet 10a having the internal electrode pattern layer 12a, these may be laminated to obtain a green laminate.

Next, the green laminate is cut along the C1 cut surface and the C2 cut surface of FIGS. 3A and 3B to obtain a green chip 4a. C1 is a cut plane parallel to the YZ axis plane, and C2 is a cut plane parallel to the ZX axis plane.

As shown in FIG. 3B, the C2 cut surfaces on both sides of the C2 cut surface that cuts the internal electrode pattern layer 12a in the nth layer cut the gap of the internal electrode pattern layer 12a. Further, the C2 cut surface obtained by cutting the internal electrode pattern layer 12a in the nth layer cuts the gap of the internal electrode pattern layer 12a in the n + 1th layer.

By obtaining the green chip 4a shown in FIG. 4A by such a cutting method, the nth internal electrode pattern layer 12a of the green chip 4a is exposed on one outer surface 5a of the green chip 4a in the Y-axis direction. The other outer surface 5a is not exposed. On the contrary, the internal electrode pattern layer 12a of the n + 1th layer of the green chip 4a is not exposed on one outer surface 5a in the Y-axis direction of the green chip 4a, but is exposed on the other outer surface 5a.

Further, on the C1 cut surface of the green chip 4a shown in FIG. 3A, that is, the outer surfaces 5c and 5c of the green chip 4a facing the X-axis direction shown in FIG. 4a, the internal electrode pattern layer 12a is exposed in all the layers. Become. The method for forming the internal electrode pattern layer 12a is not particularly limited, and the internal electrode pattern layer 12a may be formed by a thin film forming method such as thin film deposition or sputtering, in addition to a printing method and a transfer method.

The plasticizer is removed from the green chip 4a by solidification and drying, and the green chip 4a is solidified. By performing a binder removal step, a firing step, and an annealing step as necessary on the dried green chip 4a, the element main body 4 before the insulating film 16 shown in FIGS. 2A and 2B is formed is formed. can get. Further, the terminal electrodes 6 and 8 shown in FIG. 1 are not formed on the element main body 4. As shown in FIG. 4A, the perspective view of the element main body 4 before the insulating film and the terminal electrodes are formed is the same as the perspective view of the green chip 4a.

In the present embodiment, in the binder removal step, for example, the holding temperature may be set to 200 ° C. to 400 ° C. The firing step may be performed in a reducing atmosphere, for example, and the annealing step may be performed in a neutral or weakly oxidizing atmosphere. As other firing conditions or annealing conditions, for example, the holding temperature for firing is 1000 ° C to 1300 ° C, and the holding temperature for annealing is 500 ° C to 1100 ° C. The binder removal step, firing step, and annealing step may be performed continuously or independently.

In the above-described embodiment, the green laminate shown in FIGS. 3A and 3B is fragmented into the green chip 4a, and then the green chip 4a is fired to form the element main body 4. However, FIGS. 3A and 3B are shown. The green laminate shown in 3B may be fired to form a sintered body, and then the sintered body may be cut to form an individual element main body 4.

Next, as shown in FIG. 2A, the insulating film 16 is formed by applying and baking the insulating film paste on the entire surfaces of the outer surfaces 5b and 5b located on both end faces in the X-axis direction of the element main body 4. When applying the insulating film paste, the paste is applied not only to the entire surface of both end faces in the X-axis direction of the element body 4, but also to the entire surface of both end faces in the Z-axis direction of the element body 4. May be good. Further, the coating may be applied to both ends of the element body 4 in the Z-axis direction in the X-axis direction and / or both ends of the element body 4 in the Y-axis direction in the X-axis direction.

When the insulating film 16 is made of glass, the insulating film paste is obtained by kneading, for example, the above-mentioned glass raw material, a binder containing ethyl cellulose as a main component, and terpineol and acetone as dispersion media with a mixer.

The method for applying the insulating film paste to the element main body 4 is not particularly limited, and examples thereof include methods such as dipping, printing, coating, vapor deposition, and spraying. An insulating film paste is applied to the element body 4, and the element body 4 is dried, debindered, and baked to obtain the element body 4 on which the insulating film 16 is formed. The baking temperature of the insulating film paste is preferably 0 ° C. to 150 ° C. higher than the softening point of the glass contained in the insulating film paste, and more preferably 10 ° C. to 50 ° C. higher. ..

The glass component liquefied during baking easily enters the voids from the end of the inner dielectric layer 10 to the end of the inner electrode layer 12. Therefore, the insulating film 16 surely fills the voids, and not only the insulating property is enhanced, but also the moisture resistance is improved.

In the present embodiment, as shown in FIG. 2A, before forming the insulating films 16 on the outer surfaces 5b and 5b of the element body 4 facing in the X-axis direction, the cleaning process of the outer surface of the element body 4 described in detail later will be performed. I do. The insulating film 16 is formed on the outer surfaces 5b and 5b of the element main body 4 facing the X-axis direction after the cleaning process.

Next, a metal paste is applied and baked on both end faces in the Y-axis direction of the element main body 4 on which the insulating film 16 is baked, and a metal paste baking film serving as an electrode film for the terminal electrodes 6 and 8 shown in FIG. 1 is formed. Form. The method for forming the electrode film of the terminal electrodes 6 and 8 is not particularly limited, and an appropriate method such as coating / baking of a metal paste, plating, vapor deposition, and sputtering can be used.

When applying the metal paste to the end face of the element body 4 in the Y-axis direction by dipping, the metal paste may be wetted and spread on the end face of the element body 4 in the X-axis direction and the end face in the Z-axis direction. preferable. The wetting spread width in the Y-axis direction is preferably 100 μm to 200 μm. The wetting spread width can be controlled by adjusting the viscosity of the metal paste and the dip conditions. The baking temperature of the metal paste is preferably 0 ° C. to 50 ° C. higher than the softening point of the glass contained in the terminal electrodes 6 and 8.

Then, a coating layer is formed on the surface of the electrode films of the terminal electrodes 6 and 8 by plating, sputtering, or the like. The terminal electrodes 6 and 8 may be formed after the insulating film 16 is formed, or may be formed at the same time as the insulating film 16 is formed, but preferably after the insulating film 16 is formed.

In the present embodiment, before forming the terminal electrodes 6 and 8 on the outer surfaces 5a and 5a facing the Y-axis direction of the element body 4 shown in FIG. 1, the cleaning process of the outer surface of the element body 4 described in detail later is performed. You may go. The terminal electrodes 6 and 8 may be formed on the outer surfaces 5a and 5a of the element main body 4 facing the Y-axis direction after the cleaning process. If the cleaning process described later is performed before the insulating films 16 are formed on the outer surfaces 5b and 5b of the element main body 4, the cleaning process is not necessarily repeated before forming the terminal electrodes 6 and 8. You don't have to do it.

In the present embodiment, as shown in FIG. 3A, the internal electrode pattern layer is continuously formed along the X-axis direction, and as shown in FIG. 2A, the gap portion forms the insulating film 16 on the element body 4. Obtained by Therefore, the margin pattern for forming the gap portion is not formed. Therefore, unlike the conventional method, a film of a flat internal electrode pattern layer is formed on the green sheet. Therefore, the number of green chips 4a acquired per area of the green sheet can be increased as compared with the conventional case. Further, in the present embodiment, unlike the conventional case, it is not necessary to worry about the margin pattern when cutting the green laminate, so that the cutting yield is improved as compared with the conventional case.

Further, conventionally, when the green sheets are laminated, the margin pattern portion is thinner than the portion where the internal electrode pattern layer is formed, and the vicinity of the cut surface of the green chip 4a is curved when cutting. There was a problem. Further, conventionally, since a swelling is formed near the margin pattern portion of the internal electrode pattern layer, unevenness is generated in the internal electrode layer, and there is a possibility that the internal electrode or the green sheet may be deformed by laminating these. On the other hand, in the present embodiment, the margin pattern is not formed and the swelling of the internal electrode pattern layer is not formed.

Further, in the present embodiment, the internal electrode pattern layer is a flat film, no swelling of the internal electrode pattern layer is formed, and bleeding or blurring of the internal electrode pattern layer does not occur in the vicinity of the gap portion. The capacity can be improved. This effect becomes more remarkable as the element body is smaller.

Further, in the present embodiment, the insulating film 16 is formed on the element body 4 by baking the insulating film paste on the element body 4 after firing. By adopting this structure, it is possible to improve the moisture resistance of electronic components and improve the durability against changes in the external environment such as thermal shock and physical shock.

(Cleaning process of element body and formation of functional part, etc.)
As shown in FIG. 2A, the outer surface of the element body 4 is cleaned before the insulating films 16 are formed on the outer surfaces 5b and 5b of the element body 4 facing in the X-axis direction. As shown in FIG. 5A, the first foamed sheet 20 having the first adhesive surface 21 formed on the surface and the second foamed sheet 22 having the second adhesive surface 23 formed on the surface for cleaning are performed. And prepare.

In the present embodiment, the first foam sheet 20 corresponds to the first rolling member and the second foam sheet 22 corresponds to the second rolling member, but vice versa. The first foam sheet 20 is held, for example, in a lower suction stage (not shown). Further, the second foam sheet 22 is held, for example, in an upper suction stage (not shown).

The foamed sheets 20 and 22 may be the same foamed sheets or different foamed sheets. Examples of the resin constituting these foam sheets 20 and 22 include urethane, acrylic, silicone, polyester, polyurethane and the like.

Alternatively, the foamed sheets 20 and 22 may be composed of a laminated sheet of a foamed sheet and another sheet having (or not having elasticity) elasticity. Further, the foamed sheets 20 and 22 may be flexible sheets having an adhesive layer formed on the surface thereof.

It is preferable that the surfaces of these foam sheets 20 and 22 having at least the adhesive surfaces 21 and 23 have elasticity or flexibility, and the corners of the element body 4 adhere to each other when the element body 4 described later rolls. Even if it comes into contact with the surfaces 21 and 23, it is preferable that it has elasticity to the extent that it elastically dents and returns to its original state. The thickness of the elastic portion of the foam sheets 20 and 22 on the side where the adhesive surfaces 21 and 23 are located is determined by the size of the element body 4 and the like, and is 1/20 to the maximum height of the element body 4 in the Z-axis direction. About twice is preferable.

The adhesive strengths of the adhesive surfaces 21 and 23 of the foam sheets 20 and 22 may be the same or different. The adhesive strength of the adhesive surfaces 20 and 22 can also be changed depending on the material, foaming rate, foaming temperature, thickness and the like of the foamed sheets 20 and 22. For example, after cleaning of the element main body 4 on the adhesive surfaces 20 and 22, the element main body 4 is heated to a temperature higher than the foaming temperature of the respective foam sheets 20 and 22 in order to be easily taken out from the adhesive surface 20 or 22. , The adhesive strength of the adhesive surfaces 21 and 23 may be weakened.

In the present embodiment, the second foamed sheet 22 is arranged at a predetermined interval in the Z-axis direction with respect to the first foamed sheet 20, and the adhesive surfaces 21 and 23 of the sheets 20 and 22 are arranged so as to face each other. NS. A large number of element main bodies 4 are arranged in a matrix between these sheets 20 and 22 at predetermined intervals in the X-axis direction and at predetermined intervals in the Y-axis direction. In FIG. 5A, three element main bodies 4 are arranged at predetermined intervals in the X-axis direction, but in reality, a large number of element main bodies 4 are placed between the sheets 20 and 22 along the X-axis and the Y-axis. The outer surfaces are arranged in a matrix and are located above and below the element main body 4, and are attached to the adhesive surfaces 21 and 23.

The lower suction stage holding the first foam sheet 20 can move relative to the upper suction stage holding the second foam sheet 22 at least in the X-axis direction, preferably relative to the X-axis and Y-axis directions. It is movable, more preferably relative to the X-axis, Y-axis and Z-axis directions. It should be noted that the actual movement may be to move only the lower stage with respect to the upper stage, move the upper stage with respect to the lower stage, or move both stages relative to each other. You may move it.

In the present embodiment, a Z-axis load sensor (not shown) that detects a reaction force in the Z-axis direction applied to the first foam sheet 20 or the second foam sheet 22 from the element main body 4 is attached to the upper stage or the lower stage. It may have been. Further, a Z-axis load sensor (not shown) that detects a reaction force in the X-axis or Y-axis direction applied to the first foam sheet 20 or the second foam sheet 22 from the element main body 4 is attached to the upper stage or the lower stage. It may have been.

As the load sensor, for example, a load cell or the like is used. When rolling the element body 4 as shown below, the load applied to the element body 4 is detected by the load sensor so that the force detected by the load sensor on the element body 4 does not exceed a certain level. Can be controlled. As a result, when cleaning the element body 4, the damage to the element body 4 can be further reduced.

In the following description, in order to make the explanation easier to understand, the upper foam sheet 22 will be relatively moved with respect to the lower first foam sheet 20. The X-axis, Y-axis and Z-axis shown in FIGS. 5A to 9 are substantially perpendicular to each other like the X-axis, Y-axis and Z-axis shown in FIGS. Is different. The X-axis (first axis) and Y-axis (second axis) shown in FIGS. 5A to 9 are virtual axes substantially parallel to the first adhesive surface 21 of the first foam sheet 20, and the Z-axis (third axis). ) Is a virtual axis substantially perpendicular to the first adhesive surface 21.

In the present embodiment, first, in the absence of the second foam sheet 22 shown in FIG. 5A, on the surface of the first foam sheet 20, for example, an outer surface (main surface / non-exposed) located on the opposite sides of each element main body 4 to each other. (Outer surface) A large number of element bodies 4 are arranged so that one of 5c and 5c adheres to the adhesive surface 21 of the foam sheet 20, respectively. As shown in FIG. 1, the outer surfaces 5c and 5c, which are the main surfaces of the element main body 4, are outer surfaces on which the internal electrode layer 12 is not exposed. A large number of element bodies 4 are aligned so that one of the outer surfaces 5c and 5c of the outer surfaces 5c adheres to the adhesive surface 21 of the foam sheet 20. At that time, one of the outer surfaces 5c and 5c of the element main body 4 is aligned so as to face upward. For example, a large number of element bodies 4 can be aligned by using a chip transfer machine or the like. Since the internal electrode layers of the outer surfaces 5c and 5c of the element body 4 are not exposed, even if the outer surfaces 5c and 5c come into contact with the chip transfer machine or the like, the damage to the exposed outer surface of the internal electrode layer of the element body is small.

After that, the element body 4 with the outer surface 5c of the element body 4 turned upward is attached to the adhesive surface 21 of the first foam sheet 20 at predetermined intervals by using, for example, a chip transfer machine having a rubber collet or the like. They are arranged in a matrix at predetermined intervals in the X-axis and Y-axis directions. After that, another foam sheet 22 is arranged on the first foam sheet 20 in which the element main body 4 is arranged. As described above, in the present embodiment, for example, by using a chip transfer machine or the like, the damage to the exposed outer surface of the internal electrode layer in the element main body 4 is further reduced.

As shown in FIG. 5B, the second foam sheet 22 is X-axis with respect to the first foam sheet 20 with a large number of element bodies 4 sandwiched between the first foam sheet 20 and the second foam sheet 22. Move in one direction along. At that time, the element main body 4 sandwiched between the sheets 20 and 22 rotates (rolls) about the Y axis, respectively, and as shown in FIG. 5C, from the state of the element main body 4 shown in FIG. 5A. , Each rotate (roll) about 90 degrees around the Y axis.

As shown in FIG. 5B, during the rolling of the element body 4, the projection distance along the Z axis of the maximum rotation diameter of the element body 4 becomes large. When the thickness of each of the sheets 20 and 22 is sufficiently large compared to the size of the element body 4, the relative distance between the Z axes between the sheets 21 and 22 is changed during the rolling of the element body 4. You don't have to. This is because the inner surface of each of the sheets 20 and 22 is deformed so as to be recessed so that the change in the projection distance along the Z axis of the maximum rotation diameter of the element main body 4 can be absorbed.

In the present embodiment, as described above, the stage holding the foam sheets 20 and 22 can be moved in the Z-axis direction as well, and the load applied to the element body 4 when the element body 4 rolls is applied to the load sensor. May be detected by. The stages holding the foam sheets 20 and 22 are relatively moved in the Z-axis direction as well as the X-axis so that the force on the element body 4 detected by the load sensor does not exceed a certain level. You may control the movement of 22.

As shown in FIG. 5A, in the initial state, the outer surfaces 5c and 5c located on opposite sides of the element main body 4 are attached to the adhesive surfaces 21 and 23 of the foam sheets 20 and 22, respectively. After that, as shown in FIGS. 5B and 5C, the foamed sheet 22 is relatively moved relative to the foamed sheet 20 in the X-axis direction and the Z-axis direction (as necessary for the Z-axis / the same applies hereinafter). , The outer surfaces 5c and 5c of the element main body 4 attached to the adhesive surfaces 21 and 23 are switched to the outer surfaces 5b and 5b.

In the process of switching the outer surfaces 5c and 5c of the element body 4 attached to the adhesive surfaces 21 and 23 to the outer surfaces 5b and 5b, cutting chips and dust adhering to the outer surfaces 5c and 5c of the element body 4 (for example, during firing). The attached setter residue) and the like can be attached to the adhesive surfaces 21 and 23 and removed. From the state shown in FIG. 5C, by further moving the foamed sheet 22 relative to the foamed sheet 20 in the X-axis direction and the Z-axis direction, the outer surface of the element main body 4 attached to each of the adhesive surfaces 21 and 23 is formed. 5b and 5b are switched to the outer surfaces 5c and 5c. Therefore, by repeating this operation, the outer surfaces 5c and 5c and the outer surfaces 5b and 5b of the element main body 4 can be repeatedly cleaned.

For example, after or before that, as shown in FIG. 6A, the outer surfaces 5c and 5c located on opposite sides of the element body 4 adhere to the adhesive surfaces 21 and 23 of the foam sheets 20 and 22, respectively. From this state, the foamed sheet 22 may be moved relative to the foamed sheet 20 in the Y-axis direction. At that time, the foamed sheet 22 may be relatively moved with respect to the foamed sheet 20 in the Z-axis direction in the same manner as described above.

As shown in FIGS. 6B and 6C, the element main body 4 attached to the adhesive surfaces 21 and 23 by moving the foam sheet 22 relative to the foam sheet 20 in the Y-axis direction and the Z-axis direction. The outer surfaces 5c and 5c are switched to the outer surfaces 5a and 5a. By repeating the operation of moving the foam sheet 22 relative to the foam sheet 20 in the Y-axis direction and the Z-axis direction, the element body 4 is rolled in the same manner as described above, and the outer surfaces 5c and 5c of the element body 4 are rotated. And the outer surfaces 5a and 5a are cleaned.

In the drawings shown in FIGS. 6A to 6C, only a single element main body 4 is shown, but a large number of elements are spaced between the foam sheets 20 and 22 at predetermined intervals along the X-axis and the Y-axis. The main bodies 4 are arranged in a matrix. The same applies to FIGS. 7A and later.

In the present embodiment, as shown in FIGS. 5A to 5C, at least when the cleaning of the facing outer surfaces 5b and 5b of the element main body 4 is completed, or as shown in FIGS. 5A to 6C, the element main body 4 When the cleaning of all the outer surfaces 5a to 5c is completed, or at least when the cleaning of the outer surface 5b of the element main body 4 is completed as shown in FIG. 5C, only the foam sheet 22 is used as shown in FIG. 7A. Separate from the element body 4. In that case, by making the adhesive force of the adhesive surface 23 of the foamed sheet 22 smaller than the adhesive force of the adhesive surface 21 of the foamed sheet 20, it becomes easy to separate only the foamed sheet 22 from the element main body 4.

The foamed sheets 20 and 22 are each made of a foamed resin having an adhesive surface, and the composition of the foamed sheets 20 and 22 is selected so that the foaming temperatures of the foamed sheets 20 and 22 are different from each other. For example, when the foaming temperature of the foamed resin constituting the foamed sheet 20 shown in FIG. 5C is T1 and the foaming temperature of the foamed resin constituting the foamed sheet 22 is T2, T1> T2 is preferable, and T1 is also preferable. -T2 is preferably 20 ° C. or higher, more preferably 30 ° C. or higher.

In the present embodiment, the foamed resin 22 constituting the foamed sheet 20 is foamed by heating the foamed sheet 22 shown in FIG. 5C at a temperature T3 higher than the foaming temperature T2 and lower than the foaming temperature T1 of the foamed sheet 20. Instead, the foamed resin constituting the foamed sheet 22 foams. Therefore, the adhesive strength of the adhesive surface 21 of the foamed sheet 20 is maintained, but the adhesive strength of the adhesive surface 23 of the foamed sheet 22 is reduced. As a result, the foamed sheet 22 can be easily peeled off from the element body 4 without damaging the element body 4, and moreover, the foamed sheet 22 is maintained in a state of being attached to the adhesive surface 21 of the foamed sheet 20. The state is shown in FIG. 7A.

As shown in FIG. 7B, in the method of the present embodiment, the insulating film (functional portion) 16 shown in FIG. 2A is formed while maintaining the state in which the plurality of element main bodies 4 are attached to the adhesive surface 21 of the foam sheet 20. The paste film 16a to be used is formed on the outer surface (exposed outer surface) 5b where the internal electrode layer (conductor) of each element main body 4 is exposed. The paste film 16a is formed by, for example, a printing method or a dipping method. After that, the paste film 16a is dried while maintaining the state in which the plurality of element bodies 4 are attached to the adhesive surface 21 of the foamed sheet 20.

When the drying temperature (or binder removal temperature) of the paste film 16a shown in FIG. 7B is T4, the drying temperature T4 is preferably lower than the foaming temperature T1 of the foamed sheet 20. With the plurality of element bodies 4 attached to the foam sheet 20 at predetermined intervals, the foam sheet 20 can be dried by simply putting the foam sheet 20 in the drying furnace, which facilitates the drying operation. Since the drying temperature is lower than the foaming temperature of the foamed sheet 20 during the drying step, the element main body 4 is maintained in a state of being attached to the adhesive surface 21 of the foamed sheet 20. The drying temperature T4 of the paste film 16a is not particularly limited, but is preferably about 80 to 140 ° C. for example.

After that, as shown in FIG. 7C, the dried paste film 16a of each element body 4 is adhered to the third adhesive surface 31 of the third foam sheet 30 as a transfer member, and the element body is attached to the element body 20 from the first foam sheet 20. 4 is separated and transferred. In order to separate the element body 4 from the first foamed sheet 20 and transfer it, the element body 4 is heated at a temperature equal to or higher than the foaming temperature of the foamed resin constituting the first foamed sheet 20. By this heating, the adhesive surface 21 is no longer adhered, and all the element main bodies 4 attached to the adhesive surface 21 are easily transferred to the third foam sheet 30 without being damaged.

The third foamed sheet 30 is preferably made of a foamed resin having a foaming temperature higher than the foaming temperature of the foamed resin constituting the first foamed sheet 20 (preferably 20 ° C. or higher). With such a configuration, the adhesive strength of the third adhesive surface 31 of the sheet 30 can be maintained even at a heating temperature that reduces the adhesiveness of the adhesive surface 21.

After transferring a large number of element bodies 4 from the first foamed sheet 20 in a matrix on the third adhesive surface 31 of the third sheet 30, the outer surface of the element body 4 cleaned by the adhesive surface 21 of the first foamed sheet 20 ( As shown in FIG. 7D, a paste film 16a to be the insulating film 16 shown in FIG. 2A is formed on the exposed outer surface) 5b. The method for forming the paste film 16a is the same as the method for forming the paste film 16a described with reference to FIG. 7B.

After that, the paste film 16a is dried while maintaining the state in which the plurality of element bodies 4 are attached to the adhesive surface 31 of the foamed sheet 30. The drying temperature is preferably lower than the foaming temperature of the foamed sheet 30. After that, the adhesive strength of the adhesive surface 31 of the foam sheet 30 is weakened, all the element main bodies 4 are taken out from the foam sheet 30, and the paste film 16a formed on the two opposite outer surfaces 5b of each element main body 4 is baked. Perform processing. As described above, the baking temperature is preferably 0 ° C. to 150 ° C. higher than the softening point of the glass contained in the paste film 16a, and more preferably 10 ° C. to 50 ° C. higher. By the baking process, the paste film 16a of the element main body 4 becomes an insulating film 16 made of the glass film shown in FIG. 2A.

Next, a metal paste is applied and baked on both outer surfaces 5a and 5a of the element main body 4 on which the insulating film 16 is baked to form the terminal electrodes 6 and 8 shown in FIG. The method for forming the terminal electrodes 6 and 8 is as described in the section of the description of the manufacturing method of the monolithic ceramic capacitor. When forming the terminal electrodes 6 and 8 on the element body 4, at least three outer surfaces 5a of each element body 4 are formed, as shown in FIGS. 5A to 6C, in the same manner as the method for forming the insulating film 16 described above. , 5c, 5a may be cleaned, and then the terminal electrodes 6 and 8 may be formed on the element body 4.

In the present embodiment, for example, the formation of the paste film 16a as a functional portion is performed in a state where the element main body 4 is attached to the adhesive surface 21 or 31 as shown in FIG. 7B or FIG. 7D. That is, it is possible to simultaneously form the paste film 16a on a large number of element main bodies 4 adhering to the adhesive surface 21 or 31. Moreover, the first foamed sheet 20 as the first rolling member can be used as a jig for forming the paste film 16a, which contributes to the reduction of man-hours and shortens the manufacturing process. It becomes.

Further, in the present embodiment, as shown in FIG. 7C, when the element body 4 is peeled off from the first adhesive surface 21, the element body 4 is held by the third foam sheet 30 as a transfer member. By transferring a large number of element main bodies 4 attached to the first adhesive surface 21 to the third foam sheet 30 as a transfer member in the same arrangement, the element main body 4 peeled off from the first adhesive surface 21. The paste film 16a can be easily formed on the specific outer surface 5b.

(Summary of this embodiment)
In the method for manufacturing the multilayer ceramic capacitor 2 of the present embodiment, as shown in FIGS. 5A to 6C, the element main body 4 is attached to the first adhesive surface 21 (or the second foam sheet 22) of the first foam sheet 20 (or the second foam sheet 22). By simply rolling on the adhesive surface 23), cutting chips and dust adhering to the outer surface of the element main body 4 can be attached to the adhesive surface 21 or 23 (21 and 23) and removed. In this method, cutting chips and dust can be removed without using a barrel, so that the element body 4 is less damaged.

Further, since the outer surface of the element main body 4 can be cleaned without using the cleaning liquid, there is no possibility that the cleaning liquid invades the inside of the element main body 4, and it is not necessary to dry after cleaning, which simplifies the subsequent process. Can be planned. For example, immediately after cleaning, a step of forming the side gap insulating films 16 and 16 or the terminal electrodes 6 and 8 can be performed. Therefore, according to the method of the present embodiment, it is possible to easily manufacture the monolithic ceramic capacitor 2 without causing connection failure, short circuit failure, or the like.

In the above-described embodiment, the glass film is exemplified as the side gap insulating film 16, but the present invention is not limited to this, and a ceramic film, a resin film, or the like may be used.

Further, in the method of the present embodiment, the second foam sheet 22 is arranged on the first foam sheet 20 so as to sandwich the element main body 4, and the second foam sheet 22 is at least attached to the first foam sheet 20. The element body 4 is rolled on the first adhesive surface 21 by moving it relative to the X axis parallel to the first adhesive surface 21. By relatively moving the first foam sheet 20 and the second foam sheet 22, a large number of element bodies 4 arranged in a matrix between the first foam sheet 20 and the second foam sheet 22 at predetermined intervals can be obtained. By rolling at the same time, the outer surfaces 5a to 5c of the element main body 4 can be cleaned.

Further, in the method of the present embodiment, as shown in FIGS. 5A to 5C, after rolling the element body 4 along the X axis on the first adhesive surface 21, as shown in FIGS. 6A to 6C. In addition, the element body 4 is rolled along the Y axis. By rolling the element body 4 along the Y axis substantially perpendicular to the X axis, not only the outer surfaces 5c and 5b of the element bodies 4 adjacent to each other along the X axis but also the element bodies 4 adjacent to each other along the Y axis can be rolled. The outer surfaces 5c and 5a can also be cleaned.

Further, in the method of the present embodiment, when the second foamed sheet 22 is relatively moved along the X axis with respect to the first foamed sheet 20, as shown in FIG. 5B, the second foamed sheet 22 is moved to Z. It may be moved along the axis or relative to the axis. When the element body 4 is rolled, it is easier to roll the element body 4 when the distance between the first foam sheet 20 and the second foam sheet 22 in contact with the element body 4 is different along with the rotation of the element body 4 in the Z axis direction. The second foamed sheet 22 may be moved relative to the first foamed sheet 20. When rolling the element body 4, the corner portion of the element body 4 may be configured to be able to bite into the surface of the first adhesive surface 21 or the second adhesive surface 23. In that case, the first foaming may be performed. It is not always necessary to move the second foam sheet relative to the sheet 20 along the Z axis.

Further, in the method of the present embodiment, the second adhesive surface 23 is formed on the surface of the second foamed sheet 22 facing the first foamed sheet 20. Since the adhesive surface 23 is also formed on the surface of the second foam sheet 22, the outer surface of the element main body 4 can be cleaned with the adhesive surfaces 21 and 23 by reducing the number of times of rolling. Alternatively, the number of times of cleaning the outer surface of the element body 4 can be increased by the same number of times of rolling.

Further, in the present embodiment, as shown in FIG. 4A, on the outer surface 5b of the element body 4 where the insulating film 16 (see FIG. 2A) is to be formed, the internal electrode layer (conductor) 12 located inside the element body 4 is formed. Both ends in the X-axis direction, which are part of the above, are exposed. As shown in FIG. 2A, the internal electrode layer 12 formed inside the element body 4 by forming the side gap insulating film 16 on the outer surface 5b of the element body 4 where the internal electrode layer 12 is exposed. Etc. can be effectively protected, and moreover, short circuits of these internal electrode layers 12 can be effectively prevented. Further, as shown in FIG. 1, by forming the terminal electrodes 6 and 8 on the outer surfaces 5a and 5a of the element body 4 where the internal electrode layer 12 is exposed, the element body 4 is formed without causing connection failure or the like. It is possible to satisfactorily connect the terminal electrodes 6 and 8 to the internal electrode layer 12 formed inside the above.

In particular, in the present embodiment, one of the outer surfaces 5c and 5c (the main surface of the internal electrode layer 12 shown in FIG. 1, which is not the exposed surface) of the element main body 4 is the first in the absence of the second foam sheet 22 shown in FIG. 5A. 1 A large number of element bodies 4 are conveyed onto the first foam sheet 20 so as to be in contact with the foam sheet 20 by using, for example, a chip transfer machine (not shown). Therefore, the exposed surface of the internal electrode layer 12 formed on the outer surfaces 5a and 5b other than the main surface of the element main body 4 is not damaged by the vibrating transport portion. As a result, when the insulating film 16 as a functional portion is formed on the element main body 4, connection failure, short circuit failure, and the like are unlikely to occur.

Further, in the method of the present embodiment, as shown in FIGS. 5B and 5C, the element main body 4 is rolled on the first foam sheet 20, and the end portion of the internal electrode layer 12 is exposed on one outer surface. The element body 4 is held by the first foam sheet 20 so that the 5b is in contact with the first foam sheet 20. Therefore, as shown in FIG. 7A, the outer surface 5b on which the insulating film 16 shown in FIG. 2A is to be formed is placed on the first foam sheet 20 on the side opposite to the outer surface 5b adhering to the first foam sheet 20. It can be easily positioned. Further, since the element body 4 is only rolled on the adhesive surface 21 of the first foam sheet 20, there is little damage to the outer surface 5b where the end portion of the internal electrode layer 12 in the element body 4 is exposed. Further, it is also possible to remove dust and the like adhering to the outer surface 5b of the element main body 4 by adhering them to the adhesive surface 21 (and the adhesive surface 23) on the surface of the first foam sheet 20 (and the second foam sheet 22). Is.

As shown in FIG. 7B, in a state where a large number of element main bodies 4 are held on the first foam sheet 20, the outer surface 5b on the side opposite to the outer surface 5b held on the first foam sheet 20 of the element main body 4 can be easily formed. A functional part such as a paste film 16a can be formed on the surface. Further, by drying the paste film 16a at a temperature lower than the foaming temperature of the first foamed sheet 20, a large number of element bodies 4 are held in the first foamed sheet 20 without being peeled off from the sheet 20 at the same time. The paste film 16a of the element body 4 can be dried.

Further, in the present embodiment, as shown in FIGS. 5B to 5C, since the element body 4 is only rolled between the first foam sheet 20 and the second foam sheet 22, the internal electrode layer in the element body 4 is formed. There is little damage to the outer surface 5b where the end of 12 is exposed.

In the above-described embodiment, the first foam sheet 20 is associated with the first rolling member, and the second foam sheet 22 is associated with the second rolling member. However, "first" and "second" are used. Is a concept that has no meaning and may be reversed. That is, the second foam sheet 22 may be associated with the first rolling member, and the first foam sheet 20 may be associated with the second rolling member. More specifically, the vertical relationship between the first foam sheet 20 and the second foam sheet 22 in the Z-axis direction may be reversed.

Further, instead of the above-mentioned third foamed sheet 30 shown in FIG. 7C, a sheet member other than the foamed sheet, for example, a transfer member having a weak adhesive force may be used. Even in that case, since the paste film 16a as a functional portion can be contacted and transferred, the damage to the paste film 16a is small, and scratches and defects are less likely to occur in the paste film 16a. Then, by heating at a temperature equal to or higher than the foaming temperature of the first foamed sheet 20, the element main body 4 can be easily transferred from the first foamed sheet 20 to the transfer member. Further, in the element body 4, the outer surface of the element body 4 on which the paste film 16a is formed is held by the transfer member, so that the outer surface on the side opposite to the outer surface held by the transfer member of the element body 4 can be easily applied. A functional part such as a paste film 16a can be formed on the surface.

Further, in the above-described embodiment, the paste film 16a is exemplified as the functional part, but the functional part to which the method of the present invention is applied is shown in FIG. 1 in addition to the paste film 16a for the insulating film. It may be a paste film serving as terminal electrodes 6 and 8, or it may be another film.

Second Embodiment This embodiment is the same as the first embodiment except that the contents shown below are different from those of the first embodiment, and the description of common parts will be omitted. In this method, instead of shifting from the state shown in FIG. 7B to the step shown in FIG. 7C, the process shifts to the step shown in FIG. 8A.

That is, as shown in FIG. 8A, the fourth foam sheet 40 as the third rolling member is arranged on the element main body 4 arranged at predetermined intervals on the first foam sheet 20, and one of them is arranged. The element main body 4 having the paste film 16a formed on the outer surface 5b may be rolled in the X-axis direction. The method for rolling the element body 4 is the same as that of the above-described embodiment.

The fourth foamed sheet 40 has a fourth adhesive surface 41, and for example, the same one as the second foamed sheet 22 in the above-described embodiment can be used. As shown in FIG. 8B, the fourth foam sheet 40 is moved in one direction along the X axis with respect to the first foam sheet 20. At that time, the element main body 4 sandwiched between the sheets 20 and 40 rotates (rolls) about the Y axis, respectively, and as shown in FIG. 8B, from the state of the element main body 4 shown in FIG. 8A. , Each rotate (roll) about 180 degrees around the Y axis.

As a result, the outer surface 5b of the element body 4 on which the paste film 16a is not formed adheres to the fourth adhesive surface 41 of the fourth foam sheet 40. After that, in the above-described embodiment, in order to shift from FIG. 5C to the state shown in FIG. 7A, the fourth foamed sheet 22 is separated from the element main body 4 by the same method as that shown in FIG. 8B. The 40 is pulled away from the element body 4. Next, a paste film 16a is formed on the outer surface 5b of the element body 4 cleaned by rolling on the first adhesive surface 21 of the first foam sheet 20 in the same manner as in the method shown in FIG. 7B. be able to.

In the present embodiment, the foamed sheet 40 is used as the third rolling member, but an elastic sheet having substantially no adhesive surface may be used for rolling. This is because the outer surface 5b of the element body 4 on which the paste film 16a is not formed has already been cleaned by rolling on the first adhesive surface 21 of the first foam sheet 20. Further, by rolling the element body 4 using the elastic sheet having a low adhesive force as one of the rolling members, it is possible to reduce the damage to the paste film 16a already formed on the element body 4.

In the manufacturing method of the present embodiment, as shown in 8A and FIG. 8B, the element body 4 is rolled on the first foam sheet 20 without using a transfer member or the like, so that a pair of facing elements of the element body 4 are opposed to each other. A paste film 16a as a functional portion can be formed on the outer surface 16a. Since there is no need to transfer, a sheet having a high foaming temperature can be used as the first foamed sheet 20, and as a result, the drying temperature of the paste film 16a as a functional part can also be increased. That is, the drying temperature can be increased below the foaming temperature of the first foamed sheet 20. In addition, since no transfer member is required, it also contributes to a reduction in the number of parts for manufacturing.

Further, the element body 4 can be inverted by simply rolling the element body 4 on the relatively soft foam sheet 20 without the need for a transfer member, and the element body 4 can be inverted when the element body 4 is inverted. There is little damage to the main body 4. Therefore, when the paste film 16a as a functional portion is formed on the element main body 4, connection failure, short circuit failure, and the like are unlikely to occur.

Third Embodiment This embodiment is the same as the first or second embodiment except that the contents shown below are different from those of the first or second embodiment, and the description of common parts will be omitted. In this method, the process is shifted from the state shown in FIG. 7D to the process shown in FIG.

In the present embodiment, as shown in FIG. 7D, a paste film 16a to be the insulating film 16 shown in FIG. 2A is formed on the facing outer surface (exposed outer surface) 5b of each element main body 4, and then the illustration is omitted. The fourth rolling member is brought into contact with each element main body 4 so as to face the third foam sheet 30 and is relatively moved in the Y-axis direction, whereby the element main body 4 is rolled in the Y-axis direction at about 90 degrees.

As a result, as shown in FIG. 9, a plurality of element main bodies 4 are arranged on the third adhesive surface 31 of the third foam sheet 30, and the outer surface (exposed outer surface) 5a of the element main body 4 is placed on the Z axis. Arranged to face. The terminal electrode 6 shown in FIG. 1 is formed on one outer surface (exposed outer surface) 5a of the element body 4 in a state where a plurality of element bodies 4 are arranged on the third adhesive surface 31 of the third foam sheet 30. The electrode paste film 6a can be formed.

Further, in the same manner as in the above-described embodiment shown in FIGS. 7B to 7D or 7B to 8B, the outer surface (exposed outer surface) of the element body 4 on which the electrode paste film 6a of each element body 4 shown in FIG. 9 is not formed. ) It is possible to expose 5a. The terminal electrode 8 shown in FIG. 1 is formed on the outer surface (exposed outer surface) 5a of the element main body 4 on which the electrode paste film 6a of each element main body 4 shown in FIG. 9 is not formed, in the same manner as in the above-described embodiment. A base film can be formed. After that, the element main body 4 may be separated from the foamed sheet 30 or another sheet, and the paste film for the electrode and the paste film for the insulating film may be baked at the same time.

The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention.

For example, the element body 4 to which the method of the present invention is applied may be not only the element body 4 after firing shown in FIG. 4A but also the element body 4 after firing shown in FIG. 4B. In the element body 4, the side gap portion 18 is simultaneously formed of the same material as the dielectric layer 10. It is no longer necessary to form the insulating film 16 shown in FIG. 2A on the element main body, and only the terminal electrodes 6 and 8 shown in FIG. 1 need be formed.

In that case, in the step before forming the terminal electrodes 6 and 8 shown in FIG. 1 on the element body 4, the paste film 6a serving as the terminal electrodes 6 and 8 is formed on the element body 4 by the same method as the above-described embodiment. (See FIG. 9) can be formed. Further, the method of the present invention can be applied not only to the element main body 4 after firing but also to the green chip 4a before firing shown in FIG. 4A or FIG. 4B.

Further, the electronic component to which the manufacturing method of the present invention is applied is not limited to the monolithic ceramic capacitor, and can be applied to other electronic components. Examples of other electronic components include all electronic components in which a functional part is formed on the outer surface of the element body. For example, a bandpass filter, a chip inductor, a laminated three-terminal filter, a piezoelectric element, a chip thermistor, a chip varistor, and a chip resistor are exemplified. , Other surface mount (SMD) chip type electronic components and the like are exemplified.

2 ... Multilayer ceramic capacitor 4 ... Element body 4a ... Green chips 5a-5c ... Outer surface 6 ... First terminal electrode (functional part)
6a ... Electrode paste film (functional part)
8 ... 2nd terminal electrode (functional part)
10 ... Inner dielectric layer 10a ... Inner green sheet 11 ... Exterior area 11a ... Outer green sheet 12 ... Internal electrode layers 12α, 12β ... Drawer portion 12a ... Internal electrode pattern layer 13 ... Interior area 14 ... Capacitive area 15A, 15B ... Drawer Area 16 ... Insulating film (functional part)
16a ... Paste film (functional part)
18 ... Side gap portion 20 ... First foam sheet (first rolling member)
21 ... 1st adhesive surface 22 ... 2nd foam sheet (second rolling member)
23 ... 2nd adhesive surface 30 ... 3rd foam sheet (transfer member)
31 ... Third adhesive surface 40 ... Fourth foam sheet (third rolling member)
41 ... 4th adhesive surface

Claims (8)

The element body is such that one of the pair of unexposed outer surfaces located on opposite sides of the element body is in contact with the first foam sheet so that a part of the conductor located inside the element body is not exposed. In the process of transporting the above first foam sheet onto the first foam sheet,
A step of rolling the element body on the first foam sheet and holding the element body on the first foam sheet so that the exposed outer surface of one of the exposed conductors comes into contact with the element body.
A step of forming the other functional portion on the other exposed outer surface of the element body held by the first foam sheet, and a step of forming the other functional portion.
A step of drying the other functional part at a temperature lower than the foaming temperature of the first foamed sheet, and
A step of heating the first foamed sheet at a temperature equal to or higher than the foaming temperature of the first foamed sheet to transfer the element main body on which the other functional portion is formed to a transfer member.
A method for manufacturing an electronic component, comprising a step of forming one of the functional portions on the exposed outer surface of one of the element main bodies transferred to the transfer member. The second foamed sheet is arranged on the first foamed sheet so as to sandwich the element body, and the second foamed sheet is parallel to the surface of the first foamed sheet at least with respect to the first foamed sheet. The method for manufacturing an electronic component according to claim 1, wherein the element body is rolled on the first foam sheet while being relatively moved along the first axis. The foaming temperature of the second foamed sheet is lower than the foaming temperature of the first foamed sheet.
After rolling the element body on the first foamed sheet, the element body is heated at a temperature lower than the foaming temperature of the first foamed sheet and higher than the foaming temperature of the second foamed sheet, and the second foamed sheet is heated to the element. The method for manufacturing an electronic component according to claim 2, wherein the electronic component is separated from the main body. The transfer member is a third foamed sheet, and the foaming temperature of the third foamed sheet is higher than the foaming temperature of the first foamed sheet.
When the element body is transferred from the first foamed sheet to the third foamed sheet, the first foamed sheet is at a temperature lower than the foaming temperature of the third foamed sheet and higher than the foaming temperature of the first foamed sheet. The method for manufacturing an electronic component according to any one of claims 1 to 3, wherein the sheet is heated and the element body is transferred from the first foam sheet to the third foam sheet. A step of holding the element body on the first foam sheet so that one of the exposed outer surfaces on which one of the functional portions is to be formed comes into contact with each other.
A step of forming the other functional portion on the other exposed outer surface of the element body held by the first foam sheet, and a step of forming the other functional portion.
A step of drying the other functional part at a temperature lower than the foaming temperature of the first foamed sheet, and
A step of rolling the element body on the first foam sheet at least 180 degrees or more to bring the functional portion formed on the element body into contact with the first foam sheet to hold the element body. ,
A method for manufacturing an electronic component, comprising a step of forming one of the functional portions on one of the exposed outer surfaces of the element main body. A part of the conductor located inside the element body is not exposed so that one of the other pair of unexposed outer surfaces located on opposite sides of the element body comes into contact with the first foam sheet. After transporting the element body onto the first foam sheet,
The element body is rolled on the first foam sheet, and the element body is held by the first foam sheet so that the exposed outer surface of one of the exposed conductors comes into contact with the element body.
The method for manufacturing an electronic component according to claim 5, wherein the other functional portion is subsequently formed on the other exposed outer surface of the element body. The method for manufacturing an electronic component according to any one of claims 1 to 6, wherein the element body is a green laminate before firing or a ceramic chip after firing. The method for manufacturing an electronic component according to any one of claims 1 to 7, wherein the functional part is a glass film or a ceramic film.

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