JP2018098247A - Manufacturing method of multilayer ceramic electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a multilayer ceramic electronic component having an excellent cutting side surface.SOLUTION: A manufacturing method of a multilayer ceramic electronic component, comprises steps of: manufacturing a mother block including a plurality of laminated ceramic green sheets and an inner electrode pattern arranged along a plurality of boundary surfaces between the ceramic green sheets; acquiring a plurality of green chips that includes a lamination structure constructed by having a plurality of ceramic layers in a raw state and a plurality of inner electrodes by cutting the mother block along first and second direction cutting-plane lines orthogonal each other, and in which each inner electrode exposes to a cutting side surface appeared by the cutting along the first direction cutting-plate line; eliminating a metal component of the cutting side surface; performing a cutting processing by using a bite to the cutting side surface; acquiring a raw component main body by forming a raw ceramic protection layer in the cutting side surface after the cutting processing; and burning the raw component body.SELECTED DRAWING: Figure 9

Description

The present invention relates to a method for manufacturing a multilayer ceramic electronic component.

An example of the multilayer ceramic electronic component is a multilayer ceramic capacitor. In order to manufacture a multilayer ceramic capacitor, for example, a ceramic green sheet on which internal electrodes are formed is laminated, and the raw component body obtained is fired, and then external electrodes are formed on opposite end surfaces of the sintered component body. Form. As a result, a multilayer ceramic capacitor is obtained in which the internal electrodes drawn out on both end faces are electrically connected to the external electrodes.

In recent years, with the miniaturization and high functionality of electronic components, multilayer ceramic capacitors are required to be small and have high capacity. In order to reduce the size and increase the capacity of the multilayer ceramic capacitor, it is effective to increase the effective area of the internal electrodes occupying the ceramic green sheet, that is, the area of the internal electrodes facing each other.

For example, Patent Document 1 includes a step of producing a mother block including a plurality of laminated ceramic green sheets and internal electrode patterns respectively disposed along a plurality of interfaces between the ceramic green sheets; By cutting the mother block along a cutting line in the first direction and a cutting line in the second direction orthogonal to each other, the mother block has a laminated structure composed of a plurality of ceramic layers and a plurality of internal electrodes in a raw state. And a step of obtaining a plurality of green chips in which the internal electrode is exposed on a cut side surface that appears by cutting along the cutting line in the first direction, and applying a ceramic paste to the cut side surface, Forming a ceramic protective layer, and obtaining a raw component body, and firing the raw component body. Mick method of manufacturing an electronic component is disclosed.

Japanese Patent No. 5678905

In the method described in Patent Document 1, the area of the internal electrodes facing each other is increased by cutting the mother block so that the internal electrodes are exposed on the side surfaces. However, a method such as dicing is used for cutting the mother block, and the internal electrodes hang down due to the stress at the time of cutting. Therefore, the shorter the distance between the internal electrodes, the more the internal electrodes are in contact across the layers. (Hereinafter, also referred to as a short-circuit portion) is likely to occur on the cut side surface. Furthermore, the cut side surface is likely to be rough due to stress during cutting. If a chip component is manufactured in such a state, the short-circuit defect rate at the stage after degreasing increases. From the above, it has been difficult to obtain a good cut side face in the method for producing a high-capacity multilayer ceramic capacitor.

The above problem is not limited to the case of manufacturing a multilayer ceramic capacitor, but is a problem common to the case of manufacturing a multilayer ceramic electronic component other than the multilayer ceramic capacitor.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for producing a multilayer ceramic electronic component having a good cut side surface.

In the first aspect, the method for manufacturing a multilayer ceramic electronic component of the present invention includes a plurality of laminated ceramic green sheets, and internal electrode patterns respectively disposed along a plurality of interfaces between the ceramic green sheets. A step of fabricating a mother block, and cutting the mother block along a cutting line in a first direction and a cutting line in a second direction orthogonal to each other, thereby providing a plurality of ceramic layers in a raw state and a plurality of interiors And a step of obtaining a plurality of green chips, wherein the internal electrode is exposed on a cut side surface that appears by cutting along the cutting line in the first direction, A cutting process using a cutting tool and forming a raw ceramic protective layer on the cut side surface after the cutting process, Characterized in that it comprises a step of obtaining the goods body, a step of firing the raw component body.

In the first aspect of the present invention, the sagging of the internal electrode generated during cutting can be removed by performing a cutting process using a cutting tool on the cut side surface of the green chip where the internal electrode is exposed. Therefore, it is possible to prevent the occurrence of a short circuit location. As a result, a good cut side surface can be obtained.

In the first aspect of the method for manufacturing a multilayer ceramic electronic component according to the present invention, in the first aspect, the plurality of green chips arranged in the row and column directions are spaced apart from each other before the step of performing the cutting process. The method further comprises a step of rolling the plurality of green chips to align the cut side surfaces of each of the plurality of green chips into an open surface, and cutting the cut side surface as the open surface. It is preferable to carry out the treatment. In this case, it is possible to efficiently perform the cutting process on the cut side surface and the formation of the ceramic protective layer.

In the second aspect, the method for producing a multilayer ceramic electronic component of the present invention includes a plurality of laminated ceramic green sheets, and internal electrode patterns respectively disposed along a plurality of interfaces between the ceramic green sheets. And a step of producing a mother block and a laminated structure composed of a plurality of ceramic layers and a plurality of internal electrodes in a raw state by cutting the mother block along a cutting line in a first direction. And a step of obtaining a plurality of rod-shaped green block bodies in which the internal electrodes are exposed on a cut side surface that appears by cutting along the cutting line in the first direction, and cutting using a cutting tool on the cut side surface Forming a raw ceramic protective layer on the cut side surface after the cutting treatment, and forming the raw ceramic protective layer. A step of obtaining a plurality of raw component bodies by cutting the rod-shaped green block body along a cutting line in a second direction orthogonal to the first direction; and a step of firing the raw component bodies; It is characterized by providing.

In the second aspect of the present invention, the sagging side surface of the rod-shaped green block body from which the internal electrode is exposed is subjected to a cutting process using a cutting tool, thereby removing the sagging of the internal electrode that has occurred during cutting. Therefore, the occurrence of a short circuit can be prevented. As a result, a good cut side surface can be obtained.

In the second aspect of the manufacturing method of the multilayer ceramic electronic component of the present invention, in the second aspect, the plurality of rod-shaped green block bodies arranged in a predetermined direction are spaced apart from each other before the step of performing the cutting process. Then, by rolling the plurality of rod-shaped green block bodies, the method further comprises a step of aligning the cut side surfaces of the plurality of rod-shaped green block bodies to open surfaces, and forming the open surfaces. The cutting process is preferably performed on the cut side surface. In this case, it is possible to efficiently perform the cutting process on the cut side surface and the formation of the ceramic protective layer.

Hereinafter, when the first aspect and the second aspect of the present invention are not particularly distinguished, they are simply referred to as “a method for producing a multilayer ceramic electronic component of the present invention”.

In the method for producing a multilayer ceramic electronic component of the present invention, the cutting treatment is preferably performed by rotating at least one of the cutting tool and the green chip, or at least one of the cutting tool and the rod-shaped green block body. .

In the method for producing a multilayer ceramic electronic component of the present invention, the surface roughness Ra of the cut side surface after the cutting treatment is preferably 50 nm or less. By reducing the surface roughness of the cut side surface, the short-circuit defect rate can be reduced.

In the method for manufacturing a multilayer ceramic electronic component of the present invention, the raw ceramic protective layer is formed by attaching a green sheet for a ceramic protective layer or by applying a ceramic protective layer paste, The green sheet for ceramic or the paste for ceramic protective layer preferably contains substantially no Mg. To date, by forming a raw ceramic protective layer using a ceramic protective layer green sheet or ceramic protective layer paste containing Mg, a different phase is formed at the end of the internal electrode to reduce the short-circuit defect rate. The method of making it known is known. On the other hand, in the method for manufacturing a multilayer ceramic electronic component of the present invention, even if Mg is not substantially contained in the ceramic protective layer green sheet or the ceramic protective layer paste, the short-circuit defect rate can be reduced. .

In the method for manufacturing a multilayer ceramic electronic component of the present invention, the raw ceramic protective layer is preferably formed by applying a ceramic protective layer paste. Compared to the method of applying the ceramic protective layer green sheet, the method of applying the ceramic protective layer paste causes less damage to the green chip or rod-shaped green block body when forming the raw ceramic protective layer. . Therefore, the short-circuit defect rate can be further reduced.

In the method for producing a multilayer ceramic electronic component of the present invention, the thickness of the ceramic green sheet for producing the mother block is preferably 1 μm or less. In the manufacturing method of the multilayer ceramic electronic component of the present invention, since the sagging of the internal electrode is removed, even when the ceramic green sheet is thin, that is, when the distance between the internal electrodes is short, occurrence of a short-circuited portion is prevented. can do.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the laminated ceramic electronic component which has a favorable cut | disconnected side surface can be provided.

FIG. 1 is a perspective view schematically showing an example of a multilayer ceramic capacitor obtained by the method for manufacturing a multilayer ceramic electronic component of the present invention. FIG. 2 is a perspective view schematically showing an example of a component main body constituting the multilayer ceramic capacitor shown in FIG. FIG. 3 is a perspective view schematically showing an example of a green chip prepared for producing the component main body shown in FIG. FIG. 4 is a plan view schematically showing an example of a ceramic green sheet on which an internal electrode pattern prepared for producing the green chip shown in FIG. 3 is formed. FIG. 5A is a perspective view for explaining a process of laminating the ceramic green sheets shown in FIG. 4, and FIGS. 5B and 5C are laminating the ceramic green sheets shown in FIG. It is a top view for demonstrating the process to do. FIG. 6 is a perspective view for explaining a process of cutting the mother block. FIG. 7 is a perspective view illustrating a state in which a plurality of green chips arranged in the row and column directions are spaced apart from each other. FIGS. 8A and 8B are perspective views for explaining a process of rolling the green chip. FIG. 9A and FIG. 9B are diagrams for explaining a process of performing a cutting process. FIG. 10 is a diagram for explaining a process of forming a raw ceramic protective layer. 11A is an SEM image of the cut side surface of the multilayer ceramic capacitor of Comparative Example 1, and FIG. 11B is an SEM image of the cut side surface of the multilayer ceramic capacitor of Example 1. FIG.

Hereinafter, the manufacturing method of the multilayer ceramic electronic component of the present invention will be described.
However, the present invention is not limited to the following configurations, and can be applied with appropriate modifications without departing from the scope of the present invention. Note that the present invention also includes a combination of two or more desirable configurations of the present invention described below.

As an embodiment of the method for manufacturing a multilayer ceramic electronic component of the present invention, a method for manufacturing a multilayer ceramic capacitor will be described as an example. In addition, the manufacturing method of this invention is applicable also to multilayer ceramic electronic components other than a multilayer ceramic capacitor.

First, a multilayer ceramic capacitor obtained by the method for producing a multilayer ceramic electronic component of the present invention will be described.
FIG. 1 is a perspective view schematically showing an example of a multilayer ceramic capacitor obtained by the method for manufacturing a multilayer ceramic electronic component of the present invention. FIG. 2 is a perspective view schematically showing an example of a component main body constituting the multilayer ceramic capacitor shown in FIG.

A multilayer ceramic capacitor 11 shown in FIG. 1 includes a component body 12. As shown in FIG. 2, the component main body 12 has a rectangular parallelepiped shape or a substantially rectangular parallelepiped shape, and is opposed to a pair of main surfaces 13 and 14 facing each other, a pair of side surfaces 15 and 16 facing each other, and the like. And a pair of end faces 17 and 18.

FIG. 3 is a perspective view schematically showing an example of a green chip prepared for producing the component main body shown in FIG.
As will be described later, the component main body 12 shown in FIG. 2 has raw ceramic protective layers 22 and 23 on a pair of side surfaces 20 and 21 facing each other of the green chip 19 shown in FIG. It can be obtained by firing those formed respectively. In the following description, a part derived from the green chip 19 in the fired component main body 12 will be referred to as a laminated portion 24.

As shown in FIGS. 2 and 3, the laminated portion 24 in the component main body 12 includes a plurality of ceramic layers 25 extending in the direction of the main surfaces 13 and 14 and stacked in a direction perpendicular to the main surfaces 13 and 14, and ceramics. It has a laminated structure composed of a plurality of pairs of internal electrodes 26 and 27 formed along the interface between the layers 25. The component body 12 has a pair of ceramic protective layers 22 and 23 disposed on the cut side surfaces 20 and 21 of the laminate 24 to provide the side surfaces 15 and 16 respectively. The ceramic protective layers 22 and 23 preferably have the same thickness.

In FIGS. 1 and 2, for convenience of explanation, the boundary between the laminated portion 24 and each of the ceramic protective layers 22 and 23 is clearly shown, but such a boundary does not appear clearly. May be.

As shown in FIGS. 2 and 3, the internal electrode 26 and the internal electrode 27 oppose each other with the ceramic layer 25 interposed therebetween. When the internal electrode 26 and the internal electrode 27 face each other, electrical characteristics are developed. That is, a capacitance is formed in the multilayer ceramic capacitor 11 shown in FIG.

The internal electrode 26 has an exposed end exposed at the end surface 17 of the component main body 12, and the internal electrode 27 has an exposed end exposed at the end surface 18 of the component main body 12. On the other hand, since the ceramic protective layers 22 and 23 described above are disposed, the internal electrodes 26 and 27 are not exposed to the side surfaces 15 and 16 of the component body 12.

As shown in FIG. 1, the multilayer ceramic capacitor 11 is further formed on at least one pair of end surfaces 17 and 18 of the component body 12 so as to be electrically connected to the exposed ends of the internal electrodes 26 and 27, respectively. External electrodes 28 and 29 are formed, respectively.

The external electrodes 28 and 29 are respectively formed on at least one pair of end surfaces 17 and 18 of the component body 12, and in FIG. 1, the external electrodes 28 and 29 wrap around the main surfaces 13 and 14 and parts of the side surfaces 15 and 16. Has a part.

For example, Ni, Cu, Ag, Pd, an Ag—Pd alloy, Au, or the like can be used as the conductive material constituting the internal electrode.

As the ceramic material constituting the ceramic layer and the ceramic protective layer, for example, a dielectric ceramic mainly composed of BaTiO ₃ , CaTiO ₃ , SrTiO ₃ , CaZrO _3, or the like can be used.

The ceramic material constituting the ceramic protective layer is preferably at least the same as the main component of the ceramic material constituting the ceramic layer. In this case, it is particularly preferred that ceramic materials having the same composition are used for both the ceramic layer and the ceramic protective layer.

As described above, the manufacturing method of the present invention can be applied to multilayer ceramic electronic components other than multilayer ceramic capacitors. For example, when the multilayer ceramic electronic component is a piezoelectric component, a piezoelectric ceramic such as a PZT ceramic is used, and when the thermistor is a semiconductor ceramic such as a spinel ceramic.

The external electrode is preferably composed of a base layer and a plating layer formed on the base layer. For example, Cu, Ni, Ag, Pd, an Ag—Pd alloy, Au, or the like can be used as the conductive material constituting the base layer. The underlayer may be formed by applying a co-fire method in which a conductive paste is applied onto an unfired component body and simultaneously fired with the component body, and the conductive paste is applied onto the fired component body. It may be formed by applying a post-fire method. Alternatively, the underlayer may be formed by direct plating, or may be formed by curing a conductive resin including a thermosetting resin.

The plating layer formed on the base layer preferably has a two-layer structure of Ni plating and Sn plating thereon.

Next, a method for manufacturing the multilayer ceramic capacitor 11 shown in FIG. 1 will be described as an example of the method for manufacturing the multilayer ceramic electronic component of the present invention.

First, a ceramic green sheet to be a ceramic layer is prepared. For example, the ceramic green sheet is formed on a carrier film using a die coater, a gravure coater, a micro gravure coater, or the like.

The thickness of the ceramic green sheet is usually 3 μm or less, preferably 1 μm or less, and more preferably 0.6 μm or less.

Next, a conductive paste is printed on the ceramic green sheet with a predetermined pattern.

FIG. 4 is a plan view schematically showing an example of a ceramic green sheet on which an internal electrode pattern prepared for producing the green chip shown in FIG. 3 is formed.
As shown in FIG. 4, an internal electrode pattern 32 to be each of the internal electrodes 26 and 27 is formed by printing a conductive paste with a predetermined pattern on the ceramic green sheet 31 to be the ceramic layer 25. Is done. Specifically, a plurality of strip-like internal electrode patterns 32 are formed on the ceramic green sheet 31.

The thickness of the internal electrode pattern is not particularly limited, but is preferably 1.5 μm or less.

Thereafter, a stacking process is performed in which a predetermined number of ceramic green sheets on which internal electrode patterns are formed are stacked while being shifted, and a predetermined number of ceramic green sheets on which no internal electrode patterns are formed are stacked on the top and bottom.

Fig.5 (a) is a perspective view for demonstrating the process of laminating | stacking the ceramic green sheet shown in FIG.
As shown in FIG. 5A, a predetermined number of ceramic green sheets 31 on which the internal electrode patterns 32 are formed are stacked while being shifted by a predetermined interval along the width direction, that is, half the width direction dimension of the internal electrode patterns 32. . Further, a predetermined number of ceramic green sheets on which no internal electrode pattern is printed are stacked above and below.

FIGS. 5B and 5C are plan views for explaining a process of laminating the ceramic green sheets shown in FIG. FIGS. 5B and 5C are enlarged views of the first and second ceramic green sheets, respectively.
5B and 5C, a cutting line 33 in the width direction (vertical direction in FIGS. 5B and 5C) perpendicular to the direction in which the strip-shaped internal electrode pattern 32 extends, and Each part of the cutting line 34 in the longitudinal direction perpendicular to this (the left-right direction in FIGS. 5B and 5C) is shown. The strip-shaped internal electrode pattern 32 has a shape in which two internal electrodes 26 and 27 are connected to each other at respective lead portions and are continuous in the longitudinal direction. 5B and 5C, the cutting lines 33 and 34 are shown in common.

As a result of the lamination step, a mother block including a plurality of laminated ceramic green sheets and internal electrode patterns respectively arranged along a plurality of interfaces between the ceramic green sheets is obtained. The obtained mother block is pressed in the stacking direction by means such as isostatic pressing.

A plurality of green chips is obtained by cutting the pressed mother block along a cutting line in a first direction and a cutting line in a second direction orthogonal to each other. For this cutting, for example, methods such as dicing, pressing, and laser cutting are applied.

FIG. 6 is a perspective view for explaining a process of cutting the mother block.
In FIG. 6, the mother block 35 is cut along a cutting line 33 in a first direction and a cutting line 34 in a second direction orthogonal to each other to obtain a plurality of green chips 19 arranged in the row and column directions. In FIG. 6, the uppermost internal electrode pattern 32 located inside the mother block 35 is indicated by a broken line. In FIG. 6, six green chips 19 are taken out from one mother block 35, but in reality, a larger number of green chips 19 are taken out.

As shown in FIG. 3, each green chip 19 has a laminated structure including a plurality of ceramic layers 25 in a raw state and a plurality of internal electrodes 26 and 27. The cut side surfaces 20 and 21 of the green chip 19 are surfaces that appear by cutting along the cutting line 33 in the first direction, and the cutting end surfaces 36 and 37 are surfaces that appear by cutting the cutting line 34 in the second direction. All of the internal electrodes 26 and 27 are exposed on the cut side surfaces 20 and 21. Further, only the internal electrode 26 is exposed on one cut end face 36, and only the internal electrode 27 is exposed on the other cut end face 37.

In addition, as shown in FIG. 6, the mother block 35 may be cut in a state of being attached on the expandable adhesive sheet 38 so that the plurality of green chips 19 are arranged in the row and column directions. preferable. In this case, the adhesive sheet 38 can be expanded by an expanding device (not shown).

FIG. 7 is a perspective view illustrating a state in which a plurality of green chips arranged in the row and column directions are spaced apart from each other.
By extending the adhesive sheet 38 shown in FIG. 6, as shown in FIG. 7, the plurality of green chips 19 arranged in the row and column directions are in a state in which the interval between them is increased.

Subsequently, it is preferable that a rolling step is performed in which a plurality of green chips are rolled to align the cut side surfaces of the plurality of green chips to open surfaces.

FIGS. 8A and 8B are perspective views for explaining a process of rolling the green chip.
By rotating the green chip 19 shown in FIG. 8A by 90 degrees, as shown in FIG. 8B, the cut side surface 20 can be made an open surface facing upward.

A cutting process using a cutting tool is performed on the cut side surface. When performing the above-mentioned rolling process, it is preferable that a cutting process is performed with respect to the cut side surface which faced upwards by the rolling process.

The cutting process may be performed at any stage after the mother block is cut and before the raw ceramic protective layer is formed. Therefore, for example, the cutting process may be performed on the cut side surface before the rolling process, or the cutting process may be performed on the cut side surface obtained by cutting without performing the rolling process.

FIG. 9A and FIG. 9B are diagrams for explaining a process of performing a cutting process. FIG. 9A and FIG. 9B are enlarged views of the vicinity of the cut side surface shown from the end surface direction of the green chip.
As shown in FIG. 9A, a dripping 26A of the internal electrode 26 exists on the cut side surface 20 due to stress at the time of cutting. By performing a cutting process on the cut side surface 20 to the position of the cutting line XX shown in FIG. 9A, the droop 26A of the internal electrode 26 can be removed as shown in FIG. 9B. it can.

Examples of the cutting process include a cutting process by rotating a cutting tool, a cutting process by rotating a green chip, a cutting process by linear moving of a cutting tool, and a cutting process by linear moving of a green chip. These processes may be combined.

From the viewpoint of preventing the occurrence of a short-circuit portion, a cutting process by rotating a cutting tool, a cutting process by rotating a green chip, or a cutting process combining these is preferable. Specifically, a cutting process using a cutting device such as a surface planar is preferable. When the surface planar is used, the surface of the green chip can be cut by feeding the green chip in a state where the tool fixed at a predetermined cutting height is rotated. Furthermore, since the surface of the green chip is scraped off once by the cutting edge of the cutting tool, the surface of the green chip can be smoothed.

In the cutting process using a cutting tool, the material of the cutting tool is not particularly limited, but a diamond cutting tool is preferable.

The surface roughness Ra of the cut side surface after the cutting treatment is preferably 50 nm or less, and more preferably 20 nm or less. By reducing the surface roughness of the cut side surface, the short-circuit defect rate can be reduced.
In addition, surface roughness Ra can be measured using a light interference type surface roughness meter (NewView by ZYGO).

After the cutting process, a raw ceramic protective layer is formed on the cut side surface. The raw ceramic protective layer is formed by, for example, attaching a ceramic protective layer green sheet or applying a ceramic protective layer paste.

FIG. 10 is a diagram for explaining a process of forming a raw ceramic protective layer.
As shown in FIG. 10, a green ceramic protective layer 22 may be formed by applying a ceramic protective layer green sheet to the cut side surface 20 after cutting or by applying a ceramic protective layer paste. it can.

The ceramic protective layer green sheet or the ceramic protective layer paste preferably contains the same ceramic raw material as the main component of the ceramic green sheet for producing the mother block.

Moreover, it is preferable that Mg is not substantially contained in the ceramic protective layer green sheet or the ceramic protective layer paste.

After forming the raw ceramic protective layer, a drying step is performed as necessary. In the drying process, the green chip 19 on which the raw ceramic protective layer 22 is formed is placed in an oven set at 120 ° C. for 5 minutes, for example.

Next, it is preferable that a rolling process similar to the process described with reference to FIG. 8 is performed. That is, it is preferable that a rolling process is performed in which a plurality of green chips are rolled to align the cut side surfaces of the plurality of green chips to be open surfaces. In this case, by rotating the green chip by 180 degrees, the cut surface on the opposite side can be made an open surface facing upward.

Also on the opposite cut side surface, a cutting process using a cutting tool may be performed in the same manner as described above to form a raw ceramic protective layer. The conditions for the cutting process may be the same or different. Moreover, after forming a raw ceramic protective layer, a drying process is performed as needed. Thus, a raw component body is obtained.

The obtained raw component body is fired. The firing temperature is, for example, in the range of 900 ° C. or higher and 1300 ° C. or lower, although it depends on the ceramic material or metal material contained in the raw component body.

External electrodes 28 and 29 are formed by applying a conductive paste to both end surfaces 17 and 18 of the component body after firing, baking, and then plating as necessary. The application of the conductive paste may be performed on the raw component body, or the conductive paste may be baked at the same time as the raw component body is fired.

In this way, the multilayer ceramic capacitor 11 shown in FIG. 1 is manufactured.

In the embodiment described above, the mother block is cut into a cutting line in the first direction and a cutting line in the second direction to obtain a plurality of green chips, and then a cutting process is performed on the cut side surface to obtain a raw ceramic protective layer However, it can be changed as follows.

That is, by cutting the mother block along only the cutting line in the first direction, a plurality of rod-shaped green block bodies are obtained in which the internal electrodes are exposed on the cutting side surfaces that appear by cutting along the cutting line in the first direction. Then, after cutting the cut side surface to form a raw ceramic protective layer, a plurality of raw component bodies are obtained by cutting along a cutting line in the second direction. You may bake. After firing, a multilayer ceramic electronic component can be manufactured by performing the same process as in the above-described embodiment.

Examples in which the method for producing a multilayer ceramic electronic component of the present invention is disclosed more specifically below. In addition, this invention is not limited only to these Examples.

[Production of multilayer ceramic capacitors]
Example 1
A polyvinyl butyral binder, a plasticizer and ethanol as an organic solvent were added to BaTiO ₃ as a ceramic raw material, and these were wet mixed by a ball mill to prepare a ceramic slurry. Next, this ceramic slurry was formed into a sheet by a lip method to obtain a rectangular ceramic green sheet. Next, a conductive paste containing Ni was screen-printed on the ceramic green sheet to form an internal electrode pattern containing Ni as a main component.

A plurality of ceramic green sheets on which internal electrode patterns were formed were stacked while shifting in the width direction, and ceramic green sheets on which no internal electrode patterns were printed were stacked on the top and bottom to obtain a mother block. The obtained mother block was pressed in the laminating direction by an isostatic press.

The pressed mother block was cut into a chip shape to obtain a green chip in which individual internal electrodes were exposed on both end faces and both side faces. After cutting, ultrasonic cleaning with pure water was performed.

A cutting process using a cutting tool was performed on one cut side of the green chip. In Example 1, a surface planer (DAS8920 manufactured by DISCO Co., Ltd.) having a single blade with a blade width of 5 μm was used, and the processing conditions were a depth of cut of 10 μm, a table feed speed of 0.33 mm / sec, and a rotation speed of 1000 rpm.

After the cutting treatment, ultrasonic cleaning with pure water was performed, and then moisture was dried. Then, the raw ceramic protective layer was formed by affixing the green sheet for ceramic protective layers on the cut side surface after a cutting process. The composition of the ceramic protective layer green sheet is the same as the composition of the ceramic green sheet.

Also on the other cut side surface of the green chip, a cutting process using a cutting tool was performed in the same manner as described above, and then a raw ceramic protective layer was formed. As a result, a raw component body was obtained.

The obtained raw component body was degreased in a nitrogen atmosphere and then fired in a hydrogen / nitrogen mixed atmosphere. After firing, an external electrode was formed by applying and baking a conductive paste, and a multilayer ceramic capacitor of Example 1 was produced.

(Comparative Example 1)
Except that the cutting process was not performed on the cut side surface of the green chip, the external electrodes were formed in the same manner as in Example 1 to produce the multilayer ceramic capacitor of Comparative Example 1.

[Evaluation]
(Completely shorted point)
Using a scanning electron microscope (SEM), the cut side surface before forming the external electrode was photographed at a magnification of 7000 times. In 14 to 16 internal electrodes, the number of locations where Ni particles completely contact each other across the layers was measured. The results are shown in “Completely short-circuited locations” in Table 1. A case where the number of completely short-circuited portions was 0 was evaluated as ◎ (excellent), and a case where it was 1 or more was evaluated as × (impossible).

(Surface roughness)
The surface roughness Ra of the cut side surface before forming the external electrode was measured using an optical interference type surface roughness meter (New View manufactured by ZYGO). The results are shown in “Surface roughness” in Table 1. The case where the surface roughness Ra was 20 nm or less was evaluated as ◎ (excellent), the case where it was larger than 20 nm and 50 nm or less was evaluated as ◯ (good), and the case where it was larger than 50 nm was evaluated as × (impossible).

(Short rate after degreasing)
The capacitance of 100 multilayer ceramic capacitors was measured with an LCR meter, and the occurrence rate of short-circuit defects was calculated. The results are shown in “Short rate after degreasing” in Table 1. A case where the short-circuit rate after degreasing was less than 80% was evaluated as ◎ (excellent), a case where it was 80% or more and less than 100% was evaluated as ○ (good), and a case where it was 100% was evaluated as × (impossible).

As shown in Table 1, after the mother block was cut and before the raw ceramic protective layer was formed, in Comparative Example 1 in which the cutting treatment was not performed on the cut side surface, a complete short-circuit portion occurred. On the other hand, in Example 1 which performed the cutting process with respect to the cut side surface, the complete short circuit location was 0. Furthermore, in Example 1, the surface roughness of the cut side surface after the cutting treatment was small, and the post-degreasing short-circuit rate was greatly reduced as compared with Comparative Example 1.

11A is an SEM image of the cut side surface of the multilayer ceramic capacitor of Comparative Example 1, and FIG. 11B is an SEM image of the cut side surface of the multilayer ceramic capacitor of Example 1. FIG.
Similar to the results in Table 1, in Comparative Example 1 in which the cutting process was not performed on the cut side surface, as shown in FIG. In Example 1 where the treatment was performed, as shown in FIG.

11 Multilayer ceramic capacitors (multilayer ceramic electronic components)
12 Parts main body 13 and 14 Main surface 15 and 16 Side surface 17 and 18 End surface 19 Green chip 20, 21 Cutting side surface 22 and 23 Ceramic protective layer 24 Laminate part 25 Ceramic layer 26 and 27 Internal electrode 26A Internal electrode droop 28 and 29 External Electrode 31 Ceramic green sheet 32 Internal electrode pattern 33 Cutting line 34 in the first direction Cutting line 35 in the second direction Mother block 36, 37 Cutting end face 38 Adhesive sheet

Claims (9)

A step of producing a mother block including a plurality of laminated ceramic green sheets and internal electrode patterns respectively disposed along a plurality of interfaces between the ceramic green sheets;
A laminated structure including a plurality of ceramic layers and a plurality of internal electrodes in a raw state by cutting the mother block along a cutting line in a first direction and a cutting line in a second direction orthogonal to each other. And obtaining a plurality of green chips, wherein the internal electrodes are exposed on a cut side surface that appears by cutting along the cutting line in the first direction;
For the cutting side, a step of performing a cutting process using a cutting tool,
Forming a raw ceramic protective layer on the cut side surface after the cutting process to obtain a raw component body;
And a step of firing the raw component body. A method of manufacturing a multilayer ceramic electronic component, comprising: Before the step of performing the cutting process, a plurality of the green chips are rolled by rolling a plurality of the green chips in a state where a plurality of the green chips arranged in row and column directions are widened. Further comprising the step of aligning the cut side surfaces of each of the surfaces into an open surface,
The method for manufacturing a multilayer ceramic electronic component according to claim 1, wherein the cutting process is performed on the cut side surface that is the open surface. A step of producing a mother block including a plurality of laminated ceramic green sheets and internal electrode patterns respectively disposed along a plurality of interfaces between the ceramic green sheets;
By cutting the mother block along a cutting line in the first direction, the mother block has a laminated structure including a plurality of ceramic layers and a plurality of internal electrodes in a raw state, and cutting in the first direction A step of obtaining a plurality of rod-shaped green block bodies in which the internal electrode is exposed on a cut side surface that appears by cutting along a line;
For the cutting side, a step of performing a cutting process using a cutting tool,
Forming a raw ceramic protective layer on the cut side surface after the cutting treatment;
Cutting the rod-shaped green block body on which the raw ceramic protective layer is formed along a cutting line in a second direction perpendicular to the first direction to obtain a plurality of raw component bodies;
And a step of firing the raw component body. A method of manufacturing a multilayer ceramic electronic component, comprising: Before the step of performing the cutting treatment, a plurality of the rod-shaped green block bodies are rolled in a state in which the plurality of rod-shaped green block bodies arranged in a predetermined direction are widened. Further comprising the step of aligning the cut side surfaces of each of the rod-shaped green block bodies to open surfaces.
The manufacturing method of the multilayer ceramic electronic component of Claim 3 which performs the said cutting process with respect to the said cut side surface made into the said open surface. 5. The multilayer ceramic according to claim 1, wherein the cutting process is performed by rotating at least one of the cutting tool and the green chip, or at least one of the cutting tool and the rod-shaped green block body. Manufacturing method of electronic components. The method for manufacturing a multilayer ceramic electronic component according to claim 1, wherein the surface roughness Ra of the cut side surface after the cutting treatment is 50 nm or less. The raw ceramic protective layer is formed by attaching a ceramic protective layer green sheet or by applying a ceramic protective layer paste,
The method for manufacturing a multilayer ceramic electronic component according to claim 1, wherein Mg is not substantially contained in the ceramic protective layer green sheet or the ceramic protective layer paste. The said raw ceramic protective layer is a manufacturing method of the multilayer ceramic electronic component of any one of Claims 1-7 formed by apply | coating the paste for ceramic protective layers. The method for manufacturing a multilayer ceramic electronic component according to claim 1, wherein a thickness of the ceramic green sheet for producing the mother block is 1 μm or less.

Images