JP7307553B2 - Multilayer ceramic electronic component, manufacturing method of multilayer ceramic electronic component, and ceramic multilayer chip for manufacturing multilayer ceramic electronic component - Google Patents

Description

TECHNICAL FIELD The present invention relates to a multilayer ceramic electronic component having side margins, a manufacturing method thereof, and a ceramic multilayer chip for manufacturing the multilayer ceramic electronic component.

In the manufacturing method of laminated ceramic electronic components such as laminated ceramic capacitors, from the viewpoint of increasing the intersecting area of the internal electrodes, after producing an unfired laminate consisting of internal electrodes and ceramic green sheets, the surroundings of the internal electrodes are protected. There is known a technique of providing a side margin portion for For example, in Patent Document 1, a side ceramic green sheet is attached to the side surface of a green chip with internal electrodes exposed on the side surface, and the side ceramic green sheet is punched out from the side surface to form a raw ceramic protective layer. A method for manufacturing a multilayer ceramic electronic component is disclosed.

JP 2012-209539 A

However, in the technique described in Patent Document 1, when the side surface of the green chip is pressed against the side ceramic green sheet, force may be applied in a direction not perpendicular to the side ceramic sheet. As a result, the side ceramic sheet is attached to the side surface of the green chip while being displaced in the in-plane direction, and defects such as exposure of the side surface may occur.

In view of the circumstances as described above, an object of the present invention is to provide a multilayer ceramic electronic component having a side margin portion capable of preventing defects in the side margin portion attached later, a method for manufacturing the same, and manufacturing of the multilayer ceramic electronic component. To provide a ceramic laminated chip for

To achieve the above object, a multilayer ceramic electronic component according to one aspect of the present invention includes a ceramic multilayer body and side margin portions.
The ceramic laminate has a plurality of internal electrodes stacked in a first direction, and side surfaces facing the second direction on which ends of the plurality of internal electrodes are arranged in a second direction orthogonal to the first direction. , and the side surface includes an undulating portion that undulates in the second direction.
The side margin portion is formed in a sheet shape covering the side surface from the second direction.

In this configuration, a sheet-like side margin portion is formed on the side surface including the undulating portion that undulates in the second direction. The undulating portion forms an inclined surface orthogonal to a direction different from the second direction. For this reason, the side surface and the side margin part are joined in directions other than the second direction on the inclined surface. Therefore, it is possible to improve the adhesion between the side margins and the ceramic laminate, and prevent defects in the side margins such as misalignment and peeling of the side margins with respect to the side surfaces.

Specifically, the undulating portion includes at least one of a protrusion projecting outward in the second direction and a recess recessed inward in the second direction,
The convex portion or the concave portion has a top portion positioned outermost in the second direction, a bottom portion positioned innermost in the second direction, and an inclined surface connecting between the top portion and the bottom portion. , may be included.

For example, the undulation height dimension, which is the dimension in the second direction between the top portion and the bottom portion, may be 2 μm or more and 5 μm or less.
As a result, it is possible to more effectively prevent misalignment of the side margin portions with respect to the side surfaces and poor adhesion thereof, and to secure a sufficient crossing area between the internal electrodes.

For example, the undulation width dimension, which is the dimension in the first direction between the top portion and the bottom portion, may be 20 μm or more and 400 μm or less.
As a result, it is possible to more effectively prevent misalignment and poor adhesion of the side margin portion to the side surface.

A method for manufacturing a multilayer ceramic electronic component according to another aspect of the present invention includes: a plurality of internal electrodes stacked in a first direction; and ends of the plurality of internal electrodes in a second direction orthogonal to the first direction. and a side surface facing in the second direction, the side surface including an undulating portion that undulates in the second direction.
A side margin portion is formed by pressing and adhering the side surface to the ceramic sheet.

If the thickness direction of the ceramic sheet and the pressing direction do not completely coincide when the ceramic sheet is attached, a force component accompanying the pressing also acts in the in-plane direction of the ceramic sheet. Since the side surface of the ceramic laminated chip includes the undulating portion, a resistance acts in the direction of canceling this component force, so that the side surface can be prevented from moving in the in-plane direction of the ceramic sheet when pressed. Therefore, misalignment of the side margin portion with respect to the side surface, poor adhesion, and the like can be prevented.

For example, the side margin portion can be formed on the side surface by punching the ceramic sheet on the side surface.

A ceramic multilayer chip according to still another aspect of the present invention is a ceramic multilayer chip for manufacturing a multilayer ceramic electronic component, and includes a plurality of internal electrodes stacked in a first direction and side surfaces.
End portions of the plurality of internal electrodes in a second direction orthogonal to the first direction are arranged on the side surface, and the side surface faces the second direction.
The side surface includes an undulating portion that undulates in the second direction.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a multilayer ceramic electronic component having a side margin portion capable of preventing defects in the side margin portion attached later, a method for manufacturing the same, and a ceramic for manufacturing a multilayer ceramic electronic component A laminated chip can be provided.

1 is a perspective view of a laminated ceramic capacitor according to a first embodiment of the invention; FIG. FIG. 2 is a cross-sectional view of the laminated ceramic capacitor taken along line AA'; FIG. 2 is a cross-sectional view of the multilayer ceramic capacitor taken along line BB'; 4 is a cross-sectional view enlarging a part of FIG. 3; FIG. 4 is a flow chart showing a method for manufacturing the laminated ceramic capacitor. It is a perspective view which shows the manufacturing process of the said laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. It is a cross-sectional view showing a manufacturing process of the laminated ceramic capacitor. FIG. 4 is a cross-sectional view of a laminated ceramic capacitor according to a second embodiment of the invention; FIG. 15 is a cross-sectional view enlarging a part of FIG. 14;

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The drawings show mutually orthogonal X, Y and Z axes where appropriate. The X-axis, Y-axis, and Z-axis are common in all drawings.

<First embodiment>
[Structure of Multilayer Ceramic Capacitor 10]
1 to 3 are diagrams showing a multilayer ceramic capacitor 10 according to a first embodiment of the invention. FIG. 1 is a perspective view of a laminated ceramic capacitor 10. FIG. FIG. 2 is a cross-sectional view of the multilayer ceramic capacitor 10 taken along line AA' in FIG. FIG. 3 is a cross-sectional view of the multilayer ceramic capacitor 10 taken along line BB' of FIG.

A laminated ceramic capacitor 10 includes a ceramic element body 11 , a first external electrode 14 and a second external electrode 15 . The ceramic body 11 typically has two main surfaces oriented in the Z-axis direction, two end surfaces oriented in the X-axis direction, and two side surfaces oriented in the Y-axis direction. For example, the ridges connecting the surfaces of the ceramic body 11 are rounded.

The external electrodes 14 and 15 cover the end faces of the ceramic body 11 and face each other in the X-axis direction with the ceramic body 11 interposed therebetween. The external electrodes 14 and 15 extend from the end surfaces of the ceramic body 11 to the main surface and side surfaces. As a result, the external electrodes 14 and 15 have a U-shaped cross section parallel to the XZ plane and a cross section parallel to the XY plane. The shape of the external electrodes 14 and 15 is not limited to that shown in FIG.

The external electrodes 14 and 15 are made of a good electrical conductor. Good electrical conductors forming the external electrodes 14 and 15 include, for example, copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), silver (Ag), and gold (Au). and the like as a main component.

The ceramic body 11 has a ceramic laminate (laminate) 16 and side margin portions 17 . The laminate 16 has two end surfaces 16a facing the X-axis direction, two side surfaces 16b facing the Y-axis direction, and two principal surfaces 16c facing the Z-axis direction. The side margin portions 17 cover two side surfaces 16b of the laminate 16, respectively.

The laminate 16 has a capacitance forming portion 18 and cover portions 19 provided on both sides of the capacitance forming portion 18 in the Z-axis direction. The capacitance forming portion 18 has a first internal electrode 12 and a second internal electrode 13 stacked in the Z-axis direction via ceramic layers.

Each of the internal electrodes 12 and 13 is formed in a sheet shape extending along the XY plane. The first internal electrode 12 extends in the X-axis direction to one end surface 16 a and is connected to the first external electrode 14 . The second internal electrode 13 extends in the X-axis direction to the other end surface 16 a and is connected to the second external electrode 15 . As a result, when a voltage is applied between the first external electrode 14 and the second external electrode 15, a voltage is applied to the ceramic layer between the first internal electrode 12 and the second internal electrode 13, thereby A charge corresponding to the voltage is stored in 18 .

The internal electrodes 12 and 13 are made of a good electrical conductor. Nickel (Ni) is typically used as a good electrical conductor forming the internal electrodes 12 and 13. In addition, copper (Cu), palladium (Pd), platinum (Pt), silver (Ag), A metal or alloy containing gold (Au) or the like as a main component can be used.

In the ceramic body 11, dielectric ceramics with a high dielectric constant are used in order to increase the capacitance of each ceramic layer between the internal electrodes 12,13. Dielectric ceramics with a high dielectric constant include, for example, perovskite structure materials containing barium (Ba) and titanium (Ti), represented by barium titanate (BaTiO ₃ ).

Note that the ceramic layer includes strontium titanate (SrTiO ₃ ), calcium titanate (CaTiO ₃ ), magnesium titanate (MgTiO ₃ ), calcium zirconate (CaZrO ₃ ), calcium zirconate titanate (Ca( Zr, Ti)O ₃ ) system, barium zirconate (BaZrO ₃ ) system, titanium oxide (TiO ₂ ) system, or the like may be used.

The cover part 19 is formed of insulating ceramics, but may contain the dielectric ceramics used in the ceramic body 11, for example. This suppresses internal stress that may occur between the cover portion 19 and the capacitance forming portion 18 .

The internal electrodes 12 and 13 are formed over the entire width of the capacitance forming portion 18 in the Y-axis direction, and end portions 12b and 13b in the Y-axis direction are arranged on both side surfaces 16b of the laminate 16 . Side margin portions 17 are provided on both side surfaces 16b from the viewpoint of ensuring insulation between the internal electrodes 12 and 13 and between them and the outside.

The side margin portion 17 is formed in a sheet shape covering the side surface 16b from the Y-axis direction and extending along the XZ plane. The side margin portion 17 is made of insulating ceramics, but may be made of the dielectric ceramics used in the laminated body 16, like the cover portion 19, from the viewpoint of suppressing internal stress.

[Structure of Side 16b of Ceramic Laminate 16]
As shown in FIG. 3, the side surface 16b on which the side margin portion 17 is formed includes an undulating portion 20 that undulates in the Y-axis direction in this embodiment.

The undulating portion 20 includes at least one of a protrusion 21 protruding outward in the Y-axis direction and a recess 22 recessed inward in the Y-axis direction. For example, in the multilayer ceramic capacitor 10, the undulating portion 20 on the left side of FIG.

FIG. 4 is an enlarged cross-sectional view showing the vicinity of the side surface 16b of FIG.

As shown in FIG. 4A, the convex portion 21 connects the top portion 21a positioned at the outermost position in the Y-axis direction, the bottom portion 21b positioned at the innermost position in the Y-axis direction, and the top portion 21a and the bottom portion 21b. and an inclined surface 21c. The convex portion 21 extends, for example, in the X-axis direction.

A top portion 21a of the convex portion 21 is formed in a convex shape in the Y-axis direction. The top portion 21a is configured, for example, in a linear or band shape extending in the X-axis direction.
The bottom portion 21b of the convex portion 21 is positioned on the peripheral edge of the convex portion 21 and positioned on the outer edge of the inclined surface 21c. The bottom portion 21b forms, for example, a boundary portion between the substantially flat portion of the side surface 16b and the inclined surface 21c.
The inclined surface 21c intersects with the Y-axis direction at an acute angle. The inclined surface 21c is configured, for example, in a strip shape extending in the X-axis direction along the top portion 21a.

As shown in FIG. 4B, the concave portion 22 has a top portion 22a located on the outermost side in the Y-axis direction, a bottom portion 22b located on the innermost side in the Y-axis direction, and an inclination connecting the top portion 22a and the bottom portion 22b. and a surface 22c. The concave portion 22 may be recessed in a shape corresponding to the convex portion 21, and extends in the X-axis direction, for example.

A bottom portion 22b of the recess 22 is formed in a concave shape in the Y-axis direction. The bottom portion 22b is configured, for example, in a linear or strip shape extending in the X-axis direction.
A top portion 22a of the recess 22 is located on the periphery of the recess 22 and located on the outer edge of the inclined surface 22c. The top portion 22a forms, for example, a boundary portion between the substantially flat portion of the side surface 16b and the inclined surface 22c.
The inclined surface 22c intersects with the Y-axis direction at an acute angle. The inclined surface 22c is configured, for example, in a strip shape extending in the X-axis direction along the bottom portion 22b.

Since the side surface 16b has the undulating portion 20, the side margin portion 17 and the side surface 16b are joined in a plurality of directions. As a result, even when stress is applied to the joint interface between the side margin portion 17 and the side surface 16b, the adhesion of the side margin portion 17 to the side surface 16b can be ensured. Therefore, defects such as peeling of the side margin portion 17 can be prevented.

In the convex portion 21, the dimension in the Y-axis direction between the top portion 21a and the bottom portion 21b is defined as an undulation height dimension uT. The undulation height dimension uT is measured, for example, as the dimension in the Y-axis direction between the top portion 21a and the bottom portion 21b in a cross section that cuts the top portion 21a in the Z-axis direction and is perpendicular to the Y-axis direction. When the convex portion 21 (top portion 21a) is formed to extend in the X-axis direction, the cross section can be a cross section at a position that bisects the laminate 16 substantially in the X-axis direction.

Similarly, in the concave portion 22, the dimension in the Y-axis direction between the top portion 22a and the bottom portion 22b is defined as the undulation height dimension uT. The undulation height dimension uT is measured, for example, as the dimension in the Y-axis direction between the top portion 22a and the bottom portion 22b in a cross section that cuts the bottom portion 22b in the Z-axis direction and is perpendicular to the Y-axis direction. When the concave portion 22 (bottom portion 22b) is formed to extend in the X-axis direction, the cross section can be a cross section at a position where the laminate 16 is substantially divided into two equal parts in the X-axis direction.

In this embodiment, the undulation height dimension uT is 2 μm or more and 5 μm or less. When the undulation height dimension uT is 2 μm or more, the defect prevention effect of the side margin portion 17 can be exhibited sufficiently. When the undulation height dimension uT is 5 μm or less, the degree of undulation can be moderately suppressed, and a sufficient intersection area between the internal electrodes 12 and 13 can be secured.

Also, in the convex portion 21, the dimension in the Z-axis direction between the top portion 21a and the bottom portion 21b is defined as the undulation width dimension uW. Similarly to the undulation height dimension uT, the undulation width dimension uW is also measured as the dimension in the Z-axis direction between the top portion 21a and the bottom portion 21b in a cross section that cuts the top portion 21a and is perpendicular to the Y-axis direction.

Also in the concave portion 22, the dimension in the Z-axis direction between the top portion 22a and the bottom portion 22b is defined as the undulation width dimension uW. Similarly to the undulation height dimension uT, the undulation width dimension uW is also measured as the dimension in the Z-axis direction between the top portion 22a and the bottom portion 22b in a cross section that cuts the bottom portion 22b and is perpendicular to the Y-axis direction.

In this embodiment, the undulation width dimension uW is 20 μm or more and 400 μm or less. By setting the undulation width dimension uW to 20 μm or more, the width of the undulation portion 20 can be sufficiently secured, and the adhesion between the undulation portion 20 and the side margin portion 17 can be sufficiently secured. By setting the undulation width dimension uW to 400 μm or less, the defect prevention effect of the side margin portion 17 by the undulation portion 20 can be exhibited more reliably.

Further, as described below, the undulating portion 20 can prevent defects such as misalignment with respect to the side surface 16b that may occur during the formation process of the side margin portion 17. FIG.

[Manufacturing Method of Multilayer Ceramic Capacitor 10]
FIG. 5 is a flow chart showing the manufacturing method of the multilayer ceramic capacitor 10. As shown in FIG. 6 to 13 are diagrams schematically showing the manufacturing process of the multilayer ceramic capacitor 10. FIG. Hereinafter, a method for manufacturing the laminated ceramic capacitor 10 will be described along FIG. 5 with reference to FIGS. 6 to 13 as appropriate.

(Step S01: Preparation of ceramic laminated sheet 104)
In step S01, the first ceramic sheet 101 and the second ceramic sheet 102 for forming the capacitance forming portion 18 and the third ceramic sheet 103 for forming the cover portion 19 are laminated to form a ceramic laminated sheet ( Laminated sheet) 104 is produced.

Ceramic sheets 101, 102, and 103 shown in FIG. 6 are configured as unfired dielectric green sheets containing dielectric ceramics as a main component. An unfired first internal electrode 112 corresponding to the first internal electrode 12 is formed on the first ceramic sheet 101 . Unfired second internal electrodes 113 corresponding to the second internal electrodes 13 are formed on the second ceramic sheet 102 . No internal electrodes are formed on the third ceramic sheet 103 .

Each of the internal electrodes 112 and 113 has a plurality of strip-shaped electrode patterns that cross the cutting line Lx parallel to the X-axis direction and extend along the cutting line Ly parallel to the Y-axis direction. These internal electrodes 112 and 113 are formed by applying a conductive paste to the ceramic sheets 101 and 102 by a printing method or the like.

The ceramic sheets 101 and 102 are alternately laminated in the Z-axis direction as shown in FIG. A laminate of ceramic sheets 101 and 102 corresponds to the capacitance forming portion 18 . The ceramic sheets 103 are laminated on the upper and lower surfaces in the Z-axis direction of the laminate of the ceramic sheets 101 and 102 . A stack of ceramic sheets 103 corresponds to the cover portion 19 .
Note that the number of laminated ceramic sheets 101, 102, 103 and the like can be appropriately adjusted.

A laminate sheet 104 in which the internal electrodes 112 and 113 are laminated is produced by pressing the laminate of the ceramic sheets 101, 102 and 103 from the Z-axis direction.

(Step S02: Production of ceramic laminated chip 116)
In step S02, the laminated sheet 104 obtained in step S01 is cut to produce a ceramic laminated chip (laminated chip) . In this embodiment, the laminated sheet 104 is cut by press cutting in step S02.

7 to 9 are sectional views of the laminated sheet 104 for explaining this step.
As shown in FIG. 7, the laminated sheet 104 is cut by the cutting blade B along the cutting lines Lx and Ly while being attached to the holding member C. As shown in FIG. In FIG. 7, the cutting edge of the cutting blade B is arranged facing the laminated sheet 104 in the Z-axis direction.

The holding member C has, for example, a base material C1 and an adhesive layer C2, and is configured in a sheet shape that is elastically deformable in the Z-axis direction (thickness direction). The base material C1 is made of, for example, a resin material such as vinyl chloride or polypropylene, cloth, non-woven fabric, or the like. The adhesive layer C2 is composed of, for example, an acrylic adhesive, a rubber adhesive, a silicone adhesive, or the like.

Next, as shown in FIG. 8, the cutting blade B is moved downward in the Z-axis direction until the cutting blade B reaches the holding member C to cut the laminated sheet 104 . At this time, the cutting blade B is not passed through the holding member C so that the holding member C is not cut.

As the cutting blade B moves downward in the Z-axis direction, the adhesive layer C2 of the holding member C is pressed downward in the Z-axis direction via the laminated sheet 104 . As a result, the adhesive layer C2 is deformed so as to sink downward in the Z-axis direction. As the adhesive layer C2 deforms, the laminate sheet 104 also deforms so as to locally bend downward in the Z-axis direction.

The adhesive layer C2 sinks unstably due to the stress from the cutting edge of the cutting blade B and the double-edged surfaces, and deforms into an asymmetrical shape with the double-edged surfaces interposed therebetween. As a result, the laminated sheet 104 is also deformed asymmetrically on both sides of the cutting blade B, and there are places where the cutting edge of the cutting blade B is in oblique contact with the internal electrodes 112 and 113 . As the cutting edge of the cutting blade B moves downward in the Z-axis direction, the direction of the stress acting on the laminated sheet 104 by the cutting blade B changes, and the contact angles between the cutting edge and the internal electrodes 112 and 113 change continuously.

As a result, as shown in FIG. 9, a side surface 116b including the undulating portion 120 is formed as a cut surface.

By cutting the laminated sheet 104 along the respective cutting lines Lx and Ly, as shown in the cross-sectional view of FIG. and an unfired laminated chip 116 is formed. End portions 112b and 113b of the internal electrodes 112 and 113 are arranged on the side surface 116b, and an undulating portion 120 is formed.

In this embodiment, the undulating portion 120 has a convex portion 121 projecting outward in the Y-axis direction or a concave portion 122 recessed inward in the Y-axis direction. The undulation height dimension in the Y-axis direction and the undulation width dimension in the Z-axis direction of the undulating portion 120 are adjusted according to physical properties such as the thickness of the adhesive layer C2 and the adhesive strength of the adhesive layer C2.

(Step S03: Side Margin Formation)
In step S03, an unfired side margin portion 117 is formed on the side surface 116b of the laminated chip 116 obtained in step S02.

The side margin portion 117 is formed by attaching a ceramic sheet 117s for forming the side margin portion to the side surface 116b. The ceramic sheet 117s is configured as an unfired dielectric green sheet, similar to the ceramic sheets 101, 102, and 103 used in step S01. An example of a method for forming the side margin portion 117 will be described with reference to FIGS. 11 to 13. FIG.

As shown in FIG. 11, first, the laminated chip 116 is arranged such that one side surface 116b faces the ceramic sheet 117s. The other side 116b is supported by a tape T, for example. The ceramic sheet 117s is arranged on an elastic member S that is elastically deformable in the Y-axis direction (thickness direction).

Next, as shown in FIG. 12, the side surface 116b is strongly pressed against the ceramic sheet 117s. The laminated chip 116 locally sinks deeply into the elastic member S together with the ceramic sheet 117s. At this time, a shear force acts on the ceramic sheet 117s along the outer edge of the side surface 116b, and when this shear force exceeds the shear strength of the ceramic sheet 117s, the ceramic sheet 117s is punched out.

As a result, as shown in FIG. 13, a portion of the ceramic sheet 117s that has sunk along with the laminated chip 116 is cut off to form a side margin portion 117. Then, as shown in FIG.

The side margin portion 117 is also formed on the other side surface 116b by punching the ceramic sheet 117s at the side surface 116b. As a result, an unfired ceramic body is produced.

(Step S04: Firing)
In step S04, the ceramic body obtained in step S03 is fired to produce the ceramic body 11 of the multilayer ceramic capacitor 10 shown in FIGS. The sintering temperature in step S<b>04 can be determined based on the sintering temperature of the ceramic body 111 . Also, the firing can be performed, for example, in a reducing atmosphere or in a low oxygen partial pressure atmosphere.

(Step S05: External electrode formation)
In step S05, external electrodes 14 and 15 are formed on both ends of the ceramic body 11 obtained in step S04 in the X-axis direction. As an example, first, a conductive paste is applied to both ends of the ceramic body 11 in the X-axis direction, and the conductive paste is baked to form a base film. Next, one or a plurality of plating films are formed by immersing the ceramic body 11 on which the base film is formed in a plating solution and performing electrolytic plating.
Thereby, the laminated ceramic capacitor 10 as shown in FIGS. 1 to 3 is formed.

Part of the processing in step S05 may be performed before step S04. For example, before step S04, an unfired electrode material is applied to both end surfaces of the unfired ceramic body 111 in the X-axis direction. may be baked to form the underlying layers of the external electrodes 14 and 15 . Alternatively, an unfired electrode material may be applied to the binder-removed ceramic body and fired at the same time.

In the step S03 of forming the side margin portion 117, the side surface 116b of the laminated chip 116 may be arranged in a state slightly inclined from being parallel to the surface of the ceramic sheet 117s. In this case, when pressed by the side surface 116b, a force component acts not only in the thickness direction of the ceramic sheet 117s but also in the direction parallel to the surface of the ceramic sheet 117s.

If the side surface 116b is flat, the force component causes the side surface 116b to move on the surface of the ceramic sheet 117s while being pressed in the thickness direction of the ceramic sheet 117s. As a result, a shearing force acts on the ceramic sheet 117s at a position shifted from the outer edge of the side surface 116b, and the ceramic sheet 117s is separated at that position. Therefore, the side margin portion 117 is attached in a deviated state from the side surface 116b, and defects such as partial exposure of the side surface 116b and poor adhesion of the side margin portion 117 may occur.

In this embodiment, the side surface 116b has an undulating portion 120 including protrusions 121 or recesses 122 . As a result, even if a force component acts along the surface of the ceramic sheet 117 s during pressing, a force acts in the undulating portion 120 in a direction that cancels out the component force. Therefore, it is possible to prevent the side surface 116b from moving within the surface of the ceramic sheet 117s during pressing.

In this manner, the undulating portion 120 can prevent the side margin portion 117 from being displaced from the side surface 116 b , thereby preventing defects such as exposure of the side surface 116 b and poor adhesion of the side margin portion 117 .

The undulating portion 120 is formed so that the height dimension uT of the undulation is, for example, 2 μm or more and 5 μm or less after firing. Further, the undulating portion 120 is formed so that the undulating width dimension uW is, for example, 20 μm or more and 400 μm or less after firing. As a result, as will be described below, it is possible to more reliably prevent the occurrence of defects in the side margin portions 17 .

As an example of the present embodiment, samples of the multilayer ceramic capacitor 10 having different shapes of undulating portions 20 on the side surface 16b of the multilayer body 16 were produced, and the rate of occurrence of defects in the side margin portions 17 was examined. In each sample, the dimension in the X-axis direction was 1.0 mm, and the dimension in the Y-axis and Z-axis directions was 0.5 mm.

The shape of the undulating portion 20 was measured in a cross section orthogonal to the X-axis direction, which was obtained by cutting each laminated ceramic capacitor 10 at a position substantially bisected in the X-axis direction. The undulation height dimension uT in each sample was 1 μm, 2 μm, 3 μm and 5 μm. The undulation width dimension uW in each sample was 15 μm, 20 μm, 100 μm, 300 μm, 400 μm and 500 μm. Further, as a comparative example, a laminated ceramic capacitor having the same size as each sample of the example, but having a undulation height dimension uT of 0 μm and having no undulation portion was also manufactured.

A sample of the laminated ceramic capacitor 10 after fabrication is visually inspected, and if there is misalignment of the side margin portions 17, or if there is adhesion failure such as peeling of the side margin portions 17, a defect occurs. and certified. The ratio of the number of occurrences of the defects in 100 samples having the undulating portions 20 of the same shape was calculated as the defect occurrence rate of the side margin portions 17 . Table 1 shows the results.

Although not shown in Table 1, the defect incidence rate of the comparative sample without the undulating portion 20 was 10%. On the other hand, as shown in Table 1, the defect rate was 5% or less in all the samples with the undulation height dimension uT of 1 μm or more and 5 μm or less. From this result, it was confirmed that by forming the undulating portion 20 on the side surface 16b, it is possible to suppress the displacement of the side margin portion 17 and poor adhesion.

If the undulation height dimension uT is 5 μm or less, the decrease in capacitance due to the decrease in the intersection area between the internal electrodes 12 and 13 is within a range in which there is no problem.

In particular, in the sample with the undulation height dimension uT of 2 μm or more and 5 μm or less, the defect occurrence rate could be reduced to 0% by adjusting the undulation width dimension uW to 20 μm or more and 400 μm or less. From this result, by setting the undulation height dimension uT to 2 μm or more and 5 μm or less, the inclined surfaces 21 c and 22 c of the undulation portion 20 are sufficiently inclined with respect to the Y-axis direction, and the effect of suppressing the displacement of the side margin portion 17 is enhanced. It was confirmed that

In addition, by setting the undulation width dimension uW to 20 μm or more, the width in the Z-axis direction of the convex portions 21 and the concave portions 22 of the undulating portion 20 can be sufficiently secured, and poor adhesion of the side margin portions 17 can be effectively prevented. confirmed. Further, it was confirmed that by setting the undulation width dimension uW to 400 μm or less, the inclined surfaces 21c and 22c are sufficiently inclined, and the effect of suppressing displacement of the side margin portion 17 is enhanced.

<Second embodiment>
FIG. 14 is a cross-sectional view of a multilayer ceramic capacitor 10 according to a second embodiment of the invention, showing a cross section corresponding to FIG. 15 is an enlarged sectional view showing the vicinity of one side surface 16b of FIG. 14. FIG.
In this embodiment, the same reference numerals are given to the same configurations as in the first embodiment, and the different parts from the first embodiment will be mainly described.

As shown in these figures, the side surface 16b of the laminate 16 of the multilayer ceramic capacitor 10 includes an undulating portion 20 having both convex portions 21 and concave portions 22. As shown in FIG. The protrusions 21 and the recesses 22 are arranged side by side in the Z-axis direction and formed continuously.

The convex portion 21 is a region that protrudes outward in the Y-axis direction, and the concave portion 22 is a region that is recessed inward in the Y-axis direction. In the undulating portion 20 of the present embodiment, the convex portion 21 and the concave portion 22 share a partial area. In the example shown in FIG. 15, the top 21a of the projection 21 and the top 22a of the recess 22 indicate the same portion, and the bottom 21b of the projection 21 and the bottom 22b of the recess 22 indicate the same portion. Moreover, the inclined surfaces 21c and 22c connecting these also show the same portion.

Also in this embodiment, the dimension in the Y-axis direction between the top portions 21a and 22a and the bottom portions 21b and 22b is defined as the undulation height dimension uT. A dimension in the Z-axis direction between the top portions 21a and 22a and the bottom portions 21b and 22b is defined as an undulation width dimension uW. The undulation height dimension uT is preferably 2 μm or more and 5 μm or less, and the undulation width dimension uW is preferably 20 μm or more and 400 μm or less.

When the undulating portion 20 has a plurality of convex portions 21 or a plurality of concave portions 22, the undulating height dimension uT is the largest dimension in the Y-axis direction between the top portions 21a, 22a and the bottom portions 21b, 22b. is defined as The undulation width dimension uW in this case is defined as the dimension in the Z-axis direction between the top portions 21a, 22a and the bottom portions 21b, 22b where the undulation height dimension uT is measured.

Also in this embodiment, the undulating portion 20 can prevent the ceramic sheet 117s from shifting in the planar direction when the ceramic sheet 117s is pressed by the side surface 116b. As a result, it is possible to prevent defects such as misalignment of the side margin portion 17 with respect to the side surface 16b and poor adhesion.

As in the first embodiment, the undulating portion 20 having both the convex portions 21 and the concave portions 22 adjusts the physical properties such as the thickness and viscosity of the adhesive layer C2 on which the laminated sheet 104 is arranged when the laminated sheet 104 is pressed and cut. can be formed by In addition, the undulating portions 20 of the present embodiment can also be formed, for example, by periodically changing the rotational speed of the rotary blade when cutting the laminated sheet 104 with a rotary blade such as a dicer.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

In the above-described embodiment, the ceramic laminate chip to which the ceramic sheet 117s is attached is described as being unfired, but the ceramic laminate chip of the present invention may be a fired ceramic laminate. In this case, for example, an unfired ceramic sheet 117s is attached to a fired ceramic laminate chip (ceramic laminate), and then fired again to form a ceramic body.

The method of attaching the side margin portion 117 is not limited to the method of punching out the ceramic sheet 117s by the side surface 116b. For example, it may be formed by pressing and attaching a ceramic sheet cut into the same shape as the side surface 116b to the side surface 116b. In this case as well, since the side surface 116b has the undulating portion 120, it is possible to prevent the ceramic sheet from being displaced with respect to the side surface 116b during pressing, and to prevent the side margin portion 17 from being defective.

The shape of the undulating portion 20 is not limited to the configuration in which the convex portion 21 or the concave portion 22 extends in the X-axis direction. For example, a convex top portion or a concave bottom portion may have a spot-like protrusion or depression. The undulation height dimension and undulation width dimension in this case can be measured in a cross section perpendicular to the X-axis direction cut through the convex top or concave bottom.

In addition, in the above embodiments, a laminated ceramic capacitor was described as an example of a laminated ceramic electronic component, but the present invention is applicable to general laminated ceramic electronic components in which mutually paired internal electrodes are alternately arranged. Examples of such laminated ceramic electronic components include piezoelectric elements.

DESCRIPTION OF SYMBOLS 10... Laminated ceramic capacitors 12, 13... Internal electrodes 14, 15... External electrodes 16... Ceramic laminated chip (laminated chip)
Reference Signs List 17 Side margin portion 18 Capacitance forming portion 19 Cover portion 20 Convex portion 21 Convex portion 22 Concave portion 21a, 22a Top portion 21b, 22b Bottom portion 21c, 22c Inclined surface 104 Laminated sheet 112, 113 Not yet Fired internal electrodes 116 . . . Unfired ceramic laminated chips (laminated chips)
117... unfired side margin portion 117s... ceramic sheet

Claims (6)

a plurality of internal electrodes stacked in a first direction; and a side surface facing the second direction on which ends of the plurality of internal electrodes are arranged in a second direction orthogonal to the first direction, a ceramic laminate including an undulating portion whose side surface undulates in the second direction;
a sheet-like side margin portion covering the side surface from the second direction;
and
The undulating portion includes at least one of a protrusion projecting outward in the second direction and a recess recessed inward in the second direction,
The convex portion or the concave portion has a top located at the outermost side in the second direction, a bottom located at the innermost side in the second direction, and an inclined surface connecting between the top and the bottom. , including
A undulation height dimension, which is a dimension in the second direction between the top portion and the bottom portion, is 2 μm or more and 5 μm or less. a plurality of internal electrodes stacked in a first direction; and a side surface facing the second direction on which ends of the plurality of internal electrodes are arranged in a second direction orthogonal to the first direction, a ceramic laminate including an undulating portion whose side surface undulates in the second direction;
a sheet-like side margin portion covering the side surface from the second direction;
and
The undulating portion includes at least one of a protrusion projecting outward in the second direction and a recess recessed inward in the second direction,
The convex portion or the concave portion has a top located at the outermost side in the second direction, a bottom located at the innermost side in the second direction, and an inclined surface connecting between the top and the bottom. , including
A multilayer ceramic electronic component, wherein a undulation width dimension, which is a dimension in the first direction between the top portion and the bottom portion, is 20 μm or more and 400 μm or less. a plurality of internal electrodes stacked in a first direction; and a side surface facing the second direction on which ends of the plurality of internal electrodes are arranged in a second direction orthogonal to the first direction, a step of fabricating a ceramic multilayer chip including an undulating portion whose side surface undulates in the second direction;
forming a side margin portion by pressing and attaching the side surface to a ceramic sheet;
The step of fabricating the ceramic multilayer chip includes:
laminating , in the first direction, a first ceramic sheet and a second ceramic sheet for forming the capacitance forming portion, and a third ceramic sheet for forming the cover portion, to produce a ceramic laminated sheet; ,
With a sheet-like protective member elastically deformable in the first direction laid on the lower side of the ceramic laminate sheet in the first direction , the cutting blade is moved along the first direction to remove the ceramic laminate sheet. cutting the ceramic laminate sheet while deforming the cut surface;
A method for manufacturing a multilayer ceramic electronic component. A method for manufacturing a multilayer ceramic electronic component according to claim 3,
A method for manufacturing a multilayer ceramic electronic component, wherein the side margin portion is formed on the side surface by punching the ceramic sheet on the side surface. a plurality of internal electrodes stacked in a first direction;
a side surface facing the second direction on which ends of the plurality of internal electrodes are arranged in a second direction orthogonal to the first direction;
and
The side surface includes an undulating portion that undulates in the second direction,
The undulating portion includes at least one of a protrusion projecting outward in the second direction and a recess recessed inward in the second direction,
The convex portion or the concave portion has a top located at the outermost side in the second direction, a bottom located at the innermost side in the second direction, and an inclined surface connecting between the top and the bottom. , including
A ceramic multilayer chip for manufacturing a multilayer ceramic electronic component, wherein a undulation height dimension, which is a dimension in the second direction between the top portion and the bottom portion, is 2 μm or more and 5 μm or less. a plurality of internal electrodes stacked in a first direction;
a side surface facing the second direction on which ends of the plurality of internal electrodes are arranged in a second direction orthogonal to the first direction;
and
The side surface includes an undulating portion that undulates in the second direction,
The undulating portion includes at least one of a protrusion projecting outward in the second direction and a recess recessed inward in the second direction,
The convex portion or the concave portion has a top located at the outermost side in the second direction, a bottom located at the innermost side in the second direction, and an inclined surface connecting between the top and the bottom. , including
A ceramic multilayer chip for manufacturing a multilayer ceramic electronic component, wherein a undulation width dimension, which is a dimension in the first direction between the top portion and the bottom portion, is 20 μm or more and 400 μm or less.

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