JP7459812B2 - Multilayer ceramic capacitor and method for manufacturing the same - Google Patents

Description

The present invention relates to a multilayer ceramic capacitor, and more specifically, to a multilayer ceramic capacitor with improved moisture resistance.

The present invention also relates to a method for manufacturing a multilayer ceramic capacitor suitable for manufacturing the multilayer ceramic capacitor of the present invention.

A typical multilayer ceramic capacitor has a capacitance element in which multiple dielectric layers made of ceramic and multiple internal electrodes are stacked, and external electrodes are formed on the surface of the capacitance element. The internal electrodes are extended to the end faces and side faces of the capacitance element and are electrically connected to the external electrodes.

The external electrode includes, for example, a base electrode layer formed by applying and baking a conductive paste, and a plated electrode layer formed on the surface of the base electrode layer. The plating electrode layer may be composed of a plurality of layers, if necessary.

For example, Patent Document 1 (JP 2017-168488 A) discloses a multilayer ceramic capacitor equipped with external electrodes composed of a base electrode layer mainly composed of Ni or the like, a Cu-plated electrode layer formed on the surface of the base electrode layer, a Ni-plated electrode layer formed on the surface of the Cu-plated electrode layer, and a Sn-plated electrode layer formed on the surface of the Ni-plated electrode layer.

JP2017-168488A

The conventional multilayer ceramic capacitor described above maintains moisture resistance mainly by the base electrode layer of the external electrode and the Cu-plated electrode layer. That is, the base electrode layer and the Cu-plated electrode layer prevent moisture from penetrating toward the internal electrodes.

However, when the base electrode layer is formed by applying a conductive paste to the end face of the capacitive element by, for example, dipping and baking the conductive paste, the thickness of the base electrode layer becomes uneven on the end face of the capacitive element. There was a problem. That is, there was a problem in that the thickness of the base electrode layer at the center of the end face was large, but the thickness of the base electrode layer near the outer periphery of the end face was small.

This causes a problem in that the moisture resistance of the thin parts of the base electrode layer is low, allowing moisture to penetrate into the internal electrodes through these parts, lowering the IR (insulation resistance) of the multilayer ceramic capacitor. This is explained below using the drawings.

Figure 12 shows a conventional multilayer ceramic capacitor 1000. However, Figure 12 is a cross-sectional view showing a cross section parallel to the side surface of the multilayer ceramic capacitor 1000. Note that Figure 12 was created by the applicant of the present application and is not described in Patent Document 1.

The multilayer ceramic capacitor 1000 includes a capacitance element 101. The capacitance element 101 is formed by laminating a dielectric layer 101a made of ceramic, a first internal electrode 102, and a second internal electrode 103. The first internal electrode 102 is extended to one end surface of the capacitance element 101, and the second internal electrode 103 is extended to the other end surface of the capacitance element. The cross-sectional view of FIG. 12 shows one end surface side of the capacitance element 101 where the first internal electrode 102 is extended.

External electrodes 104 are formed on both end surfaces of the capacitive element 101, respectively. An external electrode 104 formed on one end surface of the capacitive element 101 is electrically connected to the first internal electrode 102 . An external electrode 104 formed on the other end surface of the capacitive element 101 is electrically connected to the second internal electrode 103.

The external electrode 104 includes a base electrode layer 108 mainly composed of Ni or the like, which is formed by applying a conductive paste and firing it, a Cu-plated electrode layer 109 formed on the base electrode layer 108, and a Cu-plated electrode layer 109 formed on the base electrode layer 108. It is composed of a Ni-plated electrode layer 110 formed on the electrode layer 109 and a Sn-plated electrode layer 111 formed on the Ni-plated electrode layer 110.

As can be seen from FIG. 12, the base electrode layer 108 has a large thickness M at the center of the end face, but a small thickness N near the outer periphery of the end face. As described above, the multilayer ceramic capacitor 1000 mainly maintains moisture resistance with the base electrode layer 108 and the Cu-plated electrode layer 109, but the thickness N near the outer periphery of the end face of the base electrode layer 108 is small. There was a problem with moisture infiltrating inside. Then, there was a problem that the IR decreased.

The present invention has been made to solve the above-mentioned problems in the conventional technology, and as a means therefor, a multilayer ceramic capacitor according to one embodiment of the present invention comprises a capacitance element having first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, and a first end face and a second end face opposing each other in a length direction perpendicular to the height direction and the width direction, and the capacitance element is formed by laminating a plurality of dielectric layers in the height direction, a first internal electrode that is arranged on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, located inside the capacitance element and exposed at the first end face, and a second internal electrode that is arranged on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, located inside the capacitance element and exposed at the second end face. a first end face of the capacitor element and a second end face of the capacitor element, the first external electrode being disposed on the first end face and electrically connected to the first internal electrode, and a second external electrode being disposed on the second end face and electrically connected to the second internal electrode, wherein the first external electrode and the second external electrode each have a base electrode layer having a metal component and a ceramic component, a Cu-plated electrode layer disposed on the base electrode layer, a Ni-plated electrode layer disposed on the Cu-plated electrode layer, and a Sn-plated electrode layer disposed on the Ni-plated electrode layer, and a recess is formed on each of the first end face and the second end face of the capacitor element, and the base electrode layer and the Cu-plated electrode layer fit into the recess.
Furthermore, a multilayer ceramic capacitor according to another embodiment of the present invention has a first main surface and a second main surface opposing each other in a height direction, a first side surface and a second side surface opposing each other in a width direction perpendicular to the height direction, and a first end surface and a second end surface opposing each other in a length direction perpendicular to the height direction and the width direction, and includes a capacitance element in which a plurality of dielectric layers are laminated in the height direction, a first internal electrode arranged on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, located inside the capacitance element and exposed at the first end surface, a second internal electrode arranged on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, located inside the capacitance element and exposed at the second end surface, a first external electrode arranged on the first end surface and electrically connected to the first internal electrode, and a second external electrode arranged on the second end surface and exposed at the second end surface. and a second external electrode electrically connected to the first internal electrode, wherein the first external electrode and the second external electrode each have a base electrode layer having a metal component and a ceramic component, a Cu-plated electrode layer arranged on the base electrode layer, a Ni-plated electrode layer arranged on the Cu-plated electrode layer, and a Sn-plated electrode layer arranged on the Ni-plated electrode layer, and a recess is formed on each of a first end face and a second end face of the capacitance element, the base electrode layer extends into the recess, the base electrode layer extending into the recess formed on the first end face is electrically connected to at least one first internal electrode, and the base electrode layer extending into the recess formed on the second end face is electrically connected to at least one second internal electrode.

In addition, a method for manufacturing a multilayer ceramic capacitor according to one embodiment of the present invention includes the steps of: preparing a plurality of ceramic green sheets; applying a conductive paste for forming an internal electrode in a desired shape to the main surfaces of a plurality of ceramic green sheets arbitrarily selected from the plurality of ceramic green sheets; stacking and integrating the plurality of ceramic green sheets to prepare an unfired capacitance element having a first main surface and a second main surface, a first side surface and a second side surface, and a first end surface and a second end surface; cutting the first end surface and the second end surface of the unfired capacitance element to form an unfired recess on each of them; and forming an underlying electrode layer of an external electrode on each of the first end surface and the second end surface including the unfired recess. The method includes the steps of: applying a conductive paste to form a capacitor element; firing the unfired capacitor element to produce a capacitor element having a first main surface and a second main surface, a first side surface and a second side surface, a first end surface and a second end surface, a plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes stacked therein, a recess formed on each of the first end surface and the second end surface, a base electrode layer of a first external electrode formed on the first end surface including the recess, and a base electrode layer of a second external electrode formed on the second end surface including the recess; forming a Cu-plated electrode layer on the base electrode layer; forming a Ni-plated electrode layer on the Cu-plated electrode layer; and forming a Sn-plated electrode layer on the Ni-plated electrode layer.

In addition, a method for manufacturing a multilayer ceramic capacitor according to another embodiment of the present invention includes the steps of: preparing a plurality of ceramic green sheets; applying a release agent in a desired shape to an arbitrarily selected area on a main surface of a ceramic green sheet arbitrarily selected from the plurality of ceramic green sheets; applying a conductive paste for forming an internal electrode in a desired shape to the main surfaces of a plurality of ceramic green sheets arbitrarily selected from the plurality of ceramic green sheets and/or to the applied release agent; stacking and integrating the plurality of ceramic green sheets to prepare an unfired capacitance element having a first main surface and a second main surface, a first side surface and a second side surface, and a first end surface and a second end surface; and applying vibration to the unfired capacitance element to partially peel off the stacked ceramic green sheets from the ceramic green sheets at the portion where the release agent is applied. The method includes the steps of forming an unsintered recess on each of the first and second end faces, applying a conductive paste for forming an underlying electrode layer of an external electrode to each of the first and second end faces including the unsintered recess, firing the unsintered capacitance element to produce a capacitance element having a first main surface and a second main surface, a first side surface and a second side surface, and a first end face and a second end face, with a plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes stacked therein, a recess formed on each of the first end face and the second end face, an underlying electrode layer of the first external electrode formed on the first end face including the recess, and an underlying electrode layer of the second external electrode formed on the second end face including the recess, forming a Cu-plated electrode layer on the underlying electrode layer, forming a Ni-plated electrode layer on the Cu-plated electrode layer, and forming a Sn-plated electrode layer on the Ni-plated electrode layer.

In addition, in the method for manufacturing a multilayer ceramic capacitor according to the above-mentioned another embodiment, the step of applying a release agent on the main surface of the ceramic green sheet and the step of applying a conductive paste on the main surface of the ceramic green sheet are , the order may be changed.

In a multilayer ceramic capacitor according to one embodiment of the present invention, a recess is formed on the end face of the capacitance element, and the base electrode layer of the external electrode is inserted into the recess, so that the thickness of the base electrode layer is increased in that area, providing excellent moisture resistance. Therefore, the multilayer ceramic capacitor according to one embodiment of the present invention has a large IR.

In addition, according to the method for manufacturing a multilayer ceramic capacitor according to one or another embodiment of the present invention, the multilayer ceramic capacitor of the present invention can be easily manufactured.

Fig. 1A is a plan view of a multilayer ceramic capacitor 100 according to a first embodiment, Fig. 1B is a side view of the multilayer ceramic capacitor 100, and Fig. 1C is a front view of the multilayer ceramic capacitor 100. 1 is a cross-sectional view of a multilayer ceramic capacitor 100. FIG. 1 is a cross-sectional view of main parts of a multilayer ceramic capacitor 100. FIG. FIG. 2 is an exploded front view of the multilayer ceramic capacitor 100. 5A to 5C are cross-sectional views showing an example of a method for manufacturing the multilayer ceramic capacitor 100. 6(D) to (F) are continuations of FIG. 5(C), and each is a cross-sectional view showing an example of a method for manufacturing the multilayer ceramic capacitor 100. FIG. 5 is a cross-sectional view of a main portion of a multilayer ceramic capacitor 200 according to a second embodiment. 8A and 8B are cross-sectional views each showing an example of a method for manufacturing the multilayer ceramic capacitor 200. FIG. 7 is a sectional view of main parts of a multilayer ceramic capacitor 300 according to a third embodiment. Fig. 10A is a plan view of a multilayer ceramic capacitor 400 according to the fourth embodiment, and Fig. 10B is a side view of the multilayer ceramic capacitor 400. FIG. 2 is a cross-sectional view of a multilayer ceramic capacitor 400. FIG. 2 is a sectional view of a main part of a conventional multilayer ceramic capacitor 1000.

Below, the embodiments for carrying out the present invention will be described with reference to the drawings. Note that each embodiment is an illustrative example of the embodiment of the present invention, and the present invention is not limited to the contents of the embodiment. It is also possible to combine the contents described in different embodiments, and the contents of such combinations are also included in the present invention. The drawings are intended to aid in understanding the specification, and may be drawn diagrammatically, and the dimensional ratios of the depicted components or between the components may not match those described in the specification. Components described in the specification may be omitted in the drawings, or may be drawn with the number of components omitted.

[First embodiment]
1(A) to (C), FIG. 2, FIG. 3, and FIG. 4 show a multilayer ceramic capacitor 100 according to a first embodiment. However, FIG. 1(A) is a plan view of the multilayer ceramic capacitor 100. FIG. 1(B) is a side view of the multilayer ceramic capacitor 100. FIG. 1C is a front view of the multilayer ceramic capacitor 100. FIG. 2 is a cross-sectional view of the multilayer ceramic capacitor 100, showing the section XX indicated by the dashed-dotted arrow in FIGS. 1(A) and 1(C). FIG. 3 is a sectional view of essential parts of the multilayer ceramic capacitor 100. FIG. 4 is an exploded front view of the multilayer ceramic capacitor 100 with the first external electrode 4 (second external electrode 5) removed.

In these figures, a view showing one end face of the capacitance element 1 of the multilayer ceramic capacitor 100 is shown as a front view, a view showing one main surface is shown as a plan view, and a view showing one side surface is shown as a side view. Each figure also shows the height direction T, length direction L, and width direction W of the multilayer ceramic capacitor 100 (capacitance element 1), and these directions may be referred to in the following description.

The multilayer ceramic capacitor 100 includes a capacitance element 1 having a rectangular parallelepiped shape. The capacitance element 1 has a first main surface 1A and a second main surface 1B that face each other in a height direction T, a first side surface 1C and a second side surface 1D that face each other in a width direction W that is perpendicular to the height direction T, and a first end surface 1E and a second end surface 1F that face each other in a length direction L that is perpendicular to both the height direction T and the width direction W.

The dimensions of the multilayer ceramic capacitor 100 are arbitrary. However, the dimension in the height direction T can be, for example, about 0.1 mm to 2.5 mm. The dimension in the width direction W can be, for example, about 0.1 mm to 2.5 mm. The dimension in the length direction L can be, for example, about 0.1 mm to 3.2 mm.

The capacitive element 1 includes a plurality of dielectric layers 1a, a plurality of first internal electrodes 2, and a plurality of second internal electrodes 3 stacked together. The dielectric layer 1a, the first internal electrode 2, and the second internal electrode 3 are stacked in the height direction T of the capacitive element 1.

The material of the capacitance element 1 (dielectric layer 1a) is arbitrary, but for example, a dielectric ceramic mainly composed of BaTiO ₃ can be used. However, instead of BaTiO ₃ , a dielectric ceramic mainly composed of another material such as CaTiO ₃ , SrTiO ₃ , CaZrO ₃ , etc. may be used.

The thickness of the dielectric layer 1a is arbitrary, but for example, it can be about 0.3 μm to 2.0 μm in the effective capacitance formation area where the first internal electrode 2 and the second internal electrode 3 are formed.

The number of dielectric layers 1a is arbitrary, but for example, in the effective capacitance formation area where the first internal electrode 2 and the second internal electrode 3 are formed, it can be about 1 to 6000 layers.

On both the top and bottom of the capacitance element 1, an outer layer (protective layer) is provided that is composed only of the dielectric layer 1a, without the first internal electrode 2 and the second internal electrode 3. The thickness of the outer layer is arbitrary, but can be, for example, about 5 μm to 150 μm. The thickness of the dielectric layer 1a in the outer layer region may be greater than the thickness of the dielectric layer 1a in the effective region of capacitance formation where the first internal electrode 2 and the second internal electrode 3 are formed (however, in Figures 1(B), 2, 3, and 4, the thickness of the dielectric layer 1a is shown as the same in the outer layer region and the effective region). The material of the dielectric layer 1a in the outer layer region may be different from the material of the dielectric layer 1a in the effective region.

As can be seen from FIG. 2, the first internal electrode 2 extends in the length direction L of the capacitive element 1 and is drawn out to the first end surface 1E of the capacitive element 1. The second internal electrode 3 extends in the length direction L of the capacitive element 1 and is drawn out to the second end surface 1F of the capacitive element 1. Note that the first internal electrodes 2 and the second internal electrodes 3 are, in principle, alternately stacked.

Although the material of the main component (metal component) of the first internal electrode 2 and the second internal electrode 3 is arbitrary, in this embodiment, Ni was used. However, other metals such as Cu, Ag, Pd, and Au may be used instead of Ni. Further, Ni, Cu, Ag, Pd, Au, etc. may be alloyed with other metals. The first internal electrode 2 and the second internal electrode 3 may contain other components such as ceramic in addition to the metal component.

The thickness of the first internal electrode 2 and the second internal electrode 3 is arbitrary, and can be, for example, about 0.3 μm to 1.5 μm.

A first external electrode 4 is formed on the first end face 1E of the capacitance element 1. A second external electrode 5 is formed on the second end face 1F.

The first external electrode 4 is formed in a cap shape, and the edge portion extends from the first end surface 1E of the capacitive element 1 to the first main surface 1A, the second main surface 1B, and the first side surface. 1C and extends to the second side surface 1D, forming a folded portion 4a.

The second external electrode 5 is formed in a cap shape, and the edge portion extends from the second end surface 1F of the capacitive element 1 to the first main surface 1A, the second main surface 1B, and the first side surface. 1C and extends to the second side surface 1D, forming a folded portion 5a.

In the multilayer ceramic capacitor 100, the first internal electrode 2 extended to the first end face 1E of the capacitance element 1 is electrically connected to the first external electrode 4. The second internal electrode 3 extended to the second end face 1F of the capacitance element 1 is electrically connected to the second external electrode 5.

The first external electrode 4 and the second external electrode 5 have the same multi-layer structure. Specifically, as shown in Figures 2 and 3, the first external electrode 4 and the second external electrode 5 each have an undercoat electrode layer 8 formed on the surface of the capacitance element 1, a Cu-plated electrode layer 9 formed on the undercoat electrode layer 8, a Ni-plated electrode layer 10 formed on the Cu-plated electrode layer 9, and a Sn-plated electrode layer 11 formed on the Ni-plated electrode layer 10.

The base electrode layer 8 is a portion that becomes the base of the first external electrode 4 and the second external electrode 5. The base electrode layer 8 also functions to improve moisture resistance. The Cu-plated electrode layer 9 mainly functions to improve moisture resistance. The Ni-plated electrode layer 10 mainly functions to improve solder heat resistance and bondability. The Sn-plated electrode layer 11 mainly functions to improve solderability.

Base electrode layer 8 includes a metal component and a ceramic component. In this embodiment, Ni is the main component of the metal component. However, the material of the main component of the metal component of the base electrode layer 8 is arbitrary, and instead of Ni, for example, Cu, Ag, etc. may be the main component. Further, Ni, Cu, Ag, etc. may be alloyed with other metals. Moreover, the main component of the ceramic component of the base electrode layer 8 is also arbitrary. However, for example, the same material as that of the capacitive element 1 (dielectric layer 1a) can be used.

The thickness of the base electrode layer 8 is arbitrary, but for example, it can be about 2 μm to 150 μm in the thicker central areas of the first end face 1E and the second end face 1F.

Although the thickness of the Cu-plated electrode layer 9 is arbitrary, it can be, for example, about 2 μm to 20 μm.

The thickness of the Ni-plated electrode layer 10 is arbitrary, but can be, for example, about 2 μm to 7 μm.

The thickness of the Sn-plated electrode layer 11 is arbitrary, but can be, for example, approximately 1 μm to 8 μm.

The multilayer ceramic capacitor 100 has a recess 6 formed on the first end face 1E and a recess 7 formed on the second end face 1F. In this embodiment, two recesses 6 are formed on the first end face 1E and two recesses 7 are formed on the second end face 1F, but the number of recesses 6, 7 is arbitrary and may be increased or decreased.

As shown in FIG. 4, in this embodiment, the recesses 6 and 7 have a width _FW and a length _FL longer than the width _FW . Although FIG. 4 shows the recess 6 formed on the first end surface 1E, the recess 7 formed on the second end surface 1F also has a similar shape. The width F _W and length F _L of the recesses 6 and 7 are arbitrary and can be set freely.

4, the direction of the length _FL of the recess 6 formed on the first end face 1E is the same as the direction in which the first internal electrode 2 exposed on the first end face 1E extends. Similarly, the direction of the length _FL of the recess 7 formed on the second end face 1F is the same as the direction in which the second internal electrode 3 exposed on the second end face 1F extends. However, the direction of the length _FL of the recesses 6, 7 is arbitrary and can be freely set.

As can be seen from FIGS. 2 and 3, the direction of the depth F _D of the recesses 6 and 7 is the same direction as the direction in which the first internal electrode 2 and the second internal electrode 3 extend.

As can be seen from FIGS. 2 and 3, a portion 8a of the base electrode layer 8 of the first external electrode 4 and a portion 9a of the Cu-plated electrode layer 9 enter into the recess 6. Similarly, a portion 8a of the base electrode layer 8 of the first external electrode 4 and a portion 9a of the Cu-plated electrode layer 9 enter into the recess 7.

The portion 8a of the base electrode layer 8 of the first external electrode 4 that extends into the recess 6 is electrically connected to the first internal electrode 2. Similarly, the portion 8a of the base electrode layer 8 of the second external electrode 5 that extends into the recess 7 is electrically connected to the second internal electrode 3.

The recesses 6, 7 are formed to increase the thickness of the base electrode layer 8 (or the base electrode layer 8 and Cu-plated electrode layer 9) of the first external electrode 4 and the second external electrode 5 in those areas, thereby improving moisture resistance. That is, the depth of the portions 8a of the base electrode layer 8 that extend into the recesses 6, 7 is added to the thickness of the base electrode layer 8, and the effective thickness of the base electrode layer 8 increases. Therefore, it is preferable to provide the recesses 6, 7 near the outer periphery of the first end face 1E and the second end face 1F of the capacitance element 1, where the thickness of the base electrode layer 8 is likely to be small.

Note that the portion 8a of the base electrode layer 8 that has entered the recess 6 and the first internal electrode 2 do not necessarily need to be electrically connected. However, the portion 8a of the base electrode layer 8 that has entered the recess 6 needs to be electrically insulated from the second internal electrode 3. Similarly, the portion 8a of the base electrode layer 8 that has entered the recess 7 and the second internal electrode 3 do not necessarily need to be electrically connected. However, the portion 8a of the base electrode layer 8 that has entered the recess 7 needs to be electrically insulated from the first internal electrode 2.

As can be seen from FIG. 2, in this embodiment, the portion 8a of the base electrode layer 8 that has entered the recess 6, the first internal electrode 2 disposed closest to the first main surface 1A side, and the The first internal electrodes 2 arranged on the main surface 1B side of the first internal electrodes 2 are electrically connected to each other. Similarly, the portion 8a of the base electrode layer 8 that has entered the recess 7, the second internal electrode 3 located closest to the first main surface 1A, and the second internal electrode 3 located closest to the second main surface 1B. The second internal electrodes 3 are electrically connected to each other. Since the thickness of the base electrode layer 8 tends to be small in these regions, the recesses 6 and 7 are formed to increase the substantial thickness of the base electrode layer 8, thereby improving moisture resistance.

In this embodiment, the portion 8a of the base electrode layer 8 that has entered the recess 6 is electrically connected to one first internal electrode 2; The portion 8a of the electrode layer 8 and the plurality of first internal electrodes 2 may be electrically connected. Similarly, the portion 8a of the base electrode layer 8 that has entered the recess 7 is electrically connected to one second internal electrode 3; however, instead of this, the base electrode layer 8 that has entered the recess 7 The portion 8a may be electrically connected to the plurality of second internal electrodes 3.

The depth _FD of the recesses 6, 7 may be any size and may be freely set. However, as shown in FIG. 3, the depth _FD of the recesses 6, 7 is preferably larger than the thickness P of the base electrode layer 8 at that portion based on the first end face 1E or the second end face 1F. In this case, the moisture resistance can be improved satisfactorily. The depth _FD of the recesses 6, 7 is preferably smaller than the length Q of the folded portions 4a, 5a of the first external electrode 4 and the second external electrode 5. If the depth _FD of the recesses 6, 7 is too large, the lengths of the first internal electrode 2 and the second internal electrode 3 must be shortened to prevent short circuits, which may reduce the capacitance of the multilayer ceramic capacitor 100.

The multilayer ceramic capacitor 100 according to this embodiment has improved moisture resistance and large IR.

(Example of manufacturing method of multilayer ceramic capacitor 100)
The multilayer ceramic capacitor 100 according to the first embodiment can be manufactured, for example, by the manufacturing method shown in FIGS. 5(A) to 6(F).

First, an unfired capacitive element 51 shown in FIG. 5(A) is manufactured. The green capacitive element 51 includes a plurality of ceramic green sheets 11a, a plurality of conductive pastes 12 for forming the first internal electrode 2, and a plurality of conductive pastes for forming the second internal electrode 3. 13 are laminated, pressurized, and integrated.

Although not shown in the figure, first, dielectric ceramic powder, binder resin, solvent, etc. are prepared and then wet-mixed to produce ceramic slurry.

Next, the ceramic slurry is applied in sheet form onto a carrier film using a die coater, gravure coater, microgravure coater, etc., and then dried to produce a ceramic green sheet.

Next, in order to form the first internal electrode 2 and the second internal electrode 3 on the main surfaces of the specified ceramic green sheets, the conductive pastes 12 and 13 prepared in advance are applied (for example, printed) in the desired pattern shape. Note that the conductive paste is not applied to the ceramic green sheets that will become the outer layers. Note that the conductive paste may be, for example, a mixture of a solvent, a binder resin, a metal powder (for example, Ni powder), etc.

Next, the ceramic green sheets are stacked in a predetermined order and integrated by heating and pressing to produce the unsintered capacitance element 51 shown in FIG. 5(A). In a typical production line, in order to manufacture a large number of multilayer ceramic capacitors 100 with high productivity, mother ceramic green sheets are prepared, conductive pastes 12 and 13 are applied to them, and the mother ceramic green sheets are stacked, pressed, and integrated to produce the mother unsintered capacitance element, and the mother unsintered capacitance element is then divided into individual pieces to produce the unsintered capacitance elements 51.

Next, as necessary, as shown in FIG. 5(B), the unsintered capacitance element 51 is subjected to barrel polishing to form roundness R at the corners and edges of the unsintered capacitance element 51.

Next, as shown in FIG. 5C, both end surfaces of the unfired capacitive element 51 are partially cut with a blade or the like to form unfired recesses 16 and 17 for forming the recesses 6 and 7. Note that the means used for cutting is not limited to the blade, and other means such as laser light irradiation may be used.

Next, as shown in FIG. 6(D), a conductive paste 18 for forming the base electrode layer 8 is applied to both end faces of the unsintered capacitance element 51, for example by dipping. The conductive paste may be, for example, a mixture of a solvent, a binder resin, a metal powder (for example, Ni powder), a ceramic powder, etc. As shown in FIG. 6(D), the conductive paste 18 is also applied to the inner walls and bottoms of the unsintered recesses 16 and 17.

Next, the unfired capacitive element 51 is fired with a predetermined profile to complete the capacitive element 1 shown in FIG. 6(E). At this time, the ceramic green sheet 11a is fired to become the dielectric layer 1a, and the conductive pastes 12 and 13 applied to the main surface of the ceramic green sheet 11a are fired at the same time to form the first internal electrode 2 and the second internal electrode. The conductive paste 18 that becomes the internal electrode 3 and is applied to the end face of the unfired capacitive element 51 is simultaneously fired and becomes the base electrode layer 8 . Furthermore, the unfired recesses 16 and 17 become recesses 6 and 7, and portions 8a of the base electrode layer 8 are formed on the inner walls and bottoms of the recesses 6 and 7. Note that the portion 8a of the base electrode layer 8 may completely fill the insides of the recesses 6 and 7.

Next, as shown in FIG. 6(F), a Cu plating electrode layer 9 is formed on the base electrode layer 8, a Ni plating electrode layer 10 is formed on the Cu plating electrode layer 9, and the Ni plating electrode layer 9 is formed on the base electrode layer 8. A Sn-plated electrode layer 11 is formed on the layer 10 to complete the multilayer ceramic capacitor 100. A portion 9a of the Cu plating electrode layer 9 is formed inside the portion 8a of the base electrode layer 8.

(Experiment 1)
In order to confirm the effectiveness of the present invention, the following Experiment 1 was conducted.

As an example, 20 multilayer ceramic capacitors 100 as described above were fabricated. As a comparative example, 20 conventional multilayer ceramic capacitors were fabricated in which the recesses 6 and 7 were omitted from the multilayer ceramic capacitor 100. All of the fabricated multilayer ceramic capacitors had the required IR value.

Next, a voltage of 3.2 V was applied to each of the multilayer ceramic capacitors of the examples and comparative examples for 72 hours in an environment with a temperature of 125°C and a humidity of 95%.

After 72 hours had passed, the IR of each multilayer ceramic capacitor was measured, and those that exceeded the standard size were considered "good," and those that fell below the standard size were classified as "defective." The defective rate in the example was 0%. The defect rate of the comparative example was 10%.

From the above, the effectiveness of the present invention was confirmed.

[Second embodiment]
FIG. 7 shows a multilayer ceramic capacitor 200 according to a second embodiment. However, it is a sectional view of a main part of the multilayer ceramic capacitor 200.

The multilayer ceramic capacitor 200 according to the second embodiment has a part of the configuration of the multilayer ceramic capacitor 100 according to the first embodiment described above. Specifically, in the multilayer ceramic capacitor 100, the recesses 6 and 7 are each formed over one dielectric layer 1a and a portion of the dielectric layers 1a laminated above and below the dielectric layer 1a. In the multilayer ceramic capacitor 200, this is changed, and recesses 26 and 27 are formed in the boundary area between two adjacent dielectric layers 1a. Then, a portion 8b of the base electrode layer 8 and a portion 9b of the Cu-plated electrode layer 9 were formed inside the recesses 26 and 27. The other configurations of the multilayer ceramic capacitor 200 were the same as those of the multilayer ceramic capacitor 100.

(One Example of a Manufacturing Method for the Multilayer Ceramic Capacitor 200)
The multilayer ceramic capacitor 200 according to the second embodiment can be manufactured, for example, by the manufacturing method shown in FIGS.

First, although not shown, the ceramic green sheet 11a is produced by the same method as shown in the production method of the first embodiment.

Next, a release agent 20 is applied to the area on the upper or lower main surface of a given ceramic green sheet 11a where recesses 26, 27 are to be formed. Any material can be used for the release agent 20, as long as it can partially release the ceramic green sheets 11a from each other by applying vibration.

Next, the conductive pastes 12 and 13 prepared in advance are applied in a desired pattern shape to the main surface of a given ceramic green sheet 11a to form the first internal electrode 2 and the second internal electrode 3. Note that the order of the process of applying the release agent 20 to the main surface of the ceramic green sheet 11a and the process of applying the conductive pastes 12 and 13 to the main surface of the ceramic green sheet 11a may be reversed.

Next, as shown in FIG. 8(A), the ceramic green sheets 11a are stacked in a predetermined order and integrated by heat-pressing, thereby producing an unfired capacitive element 51.

Next, as shown in FIG. 8B, the unfired capacitive element 51 is subjected to barrel polishing to form rounded corners and ridges of the unfired capacitive element 51, and the release agent 20 is removed by the vibration of the barrel polishing. The ceramic green sheets 11a are partially peeled off from each other to form unfired recesses 56 and 57. Note that at this time, the conductive pastes 12 and 13 inside the unfired recesses 56 and 57 are also removed by the vibration.

Next, although not shown, a conductive paste 18 for forming the base electrode layer 8 is applied to both end faces of the unsintered capacitance element 51, for example by dipping, in the same manner as in the manufacturing method of the first embodiment.

Next, the unfired capacitive element 51 is fired with a predetermined profile to complete the capacitive element 1. At this time, the ceramic green sheet 11a is fired to become the dielectric layer 1a, and the conductive pastes 12 and 13 applied to the main surface of the ceramic green sheet 11a are fired at the same time to form the first internal electrode 2 and the second internal electrode. The conductive paste 18 that becomes the internal electrode 3 and is applied to the end face of the unfired capacitive element 51 is simultaneously fired and becomes the base electrode layer 8 . The unfired recesses 56 and 57 become recesses 26 and 27, and portions 8b of the base electrode layer 8 are formed on the inner walls and bottoms of the recesses 26 and 27.

Next, a Cu-plated electrode layer 9 is formed on the base electrode layer 8, a Ni-plated electrode layer 10 is formed on the Cu-plated electrode layer 9, and a Sn-plated electrode layer is formed on the Ni-plated electrode layer 10. Then, the multilayer ceramic capacitor 200 is completed. A portion 9b of the Cu plating electrode layer 9 is formed inside the portion 8b of the base electrode layer 8.

In the multilayer ceramic capacitor 200 according to the second embodiment, the moisture resistance of the portions of the first external electrode 4 and the second external electrode 5 where the recesses 26 and 27 are formed is also improved, and the IR is increased.

[Third embodiment]
Fig. 9 shows a multilayer ceramic capacitor 300 according to the third embodiment. Fig. 9 is a cross-sectional view of a main portion of the multilayer ceramic capacitor 300. Note that Fig. 9 shows the recess 36 and the first external electrode 4 formed on the first end face 1E of the capacitance element 1, but a recess 37 and a second external electrode 5 are also formed on the second end face 1F of the capacitance element 1 in the same manner.

The multilayer ceramic capacitor 300 according to the third embodiment also has a part of the configuration of the multilayer ceramic capacitor 100 according to the first embodiment described above. Specifically, in the multilayer ceramic capacitor 100, the portion 8a of the base electrode layer 8 formed inside the recess 6 (recess 7) is electrically connected to one first internal electrode 2 (second internal electrode 3). However, the multilayer ceramic capacitor 300 changes this and connects the portion 8c of the base electrode layer 8 formed inside the recess 36 (recess 37) to the plurality of first internal electrodes 2 (second It was electrically connected to the internal electrode 3). Note that a portion 9c of the Cu plating electrode layer 9 is formed inside the portion 8c of the base electrode layer 8. The other configurations of the multilayer ceramic capacitor 300 were the same as those of the multilayer ceramic capacitor 100.

The multilayer ceramic capacitor 300 according to the third embodiment also has improved moisture resistance in the areas where the recesses 36, 37 of the first external electrode 4 and the second external electrode 5 are formed, resulting in a large IR.

[Fourth embodiment]
10A, 10B, and 11 show a multilayer ceramic capacitor 400 according to the fourth embodiment. Fig. 10A is a plan view of the multilayer ceramic capacitor 400. Fig. 10B is a side view of the multilayer ceramic capacitor 400. Fig. 11 is a cross-sectional view of the multilayer ceramic capacitor 400, showing the Y-Y portion indicated by the dashed dotted line arrow in Fig. 10A.

The multilayer ceramic capacitors 100, 200, and 300 according to the first to third embodiments each include a first external electrode 4 and a second external electrode 5, which are a pair of external electrodes. It was a capacitor. The multilayer ceramic capacitor 400 of the fourth embodiment constitutes a three-terminal capacitor by further forming third external electrodes 40a and 40b in addition to the first external electrode 4 and the second external electrode 5. ing.

In the multilayer ceramic capacitors 100, 200, and 300, the first internal electrode 2 and the second internal electrode 3 are alternately stacked inside the capacitance element 1. Instead, in the multilayer ceramic capacitor 400 of the fourth embodiment, the third internal electrode 44, the first internal electrode 2, and the second internal electrode 3 are repeatedly stacked in this order inside the capacitance element 1.

Each third internal electrode 44 is drawn out to both the first side surface 1C and the second side surface 1D of the capacitance element 1. The third internal electrode 44 drawn out to the first side surface 1C is connected to the third external electrode 40a, and the third internal electrode 44 drawn out to the second side surface 1D is connected to the third external electrode 40b. The third external electrode 40a and the third external electrode 40b may be electrically connected to each other via the first main surface 1A and/or the second main surface 1B of the capacitance element 1.

In the multilayer ceramic capacitor 400, two recesses 46 are formed on the first side surface 1C of the capacitive element 1, and two recesses 47 are formed on the second side surface 1D.

Similarly to the first external electrode 4 and the second external electrode 5, the third external electrodes 40a and 40b include a base electrode layer 8, a Cu plating electrode layer 9, a Ni plating electrode layer 10, and a Sn plating electrode layer. 11 are laminated. A portion 8d of the base electrode layer 8 and a portion 9d of the Cu-plated electrode layer 9 are inserted into the recesses 46 and 47. The third internal electrode 44 stacked on top and the third internal electrode 44 stacked on the bottom are connected to the portion 8a of the base electrode layer 8 that has entered the inside of the recess 46 and the inside of the recess 47, respectively. They are electrically connected to the portions 8a of the base electrode layer 8 that have entered the base electrode layer 8. The other configuration of the multilayer ceramic capacitor 400 was the same as the multilayer ceramic capacitor 100 of the first embodiment.

The multilayer ceramic capacitor 400 can be used as a three-terminal capacitor. That is, the multilayer ceramic capacitor 400 can be used as a three-terminal capacitor by dividing the power supply line or signal line in the circuit, connecting the first external electrode 4 to one of the divided lines, connecting the second external electrode 5 to the other of the divided lines, and connecting the third external electrodes 40a and 40b to ground.

The multilayer ceramic capacitor 400 according to the fourth embodiment also has improved moisture resistance in the portions of the third external electrodes 40a, 40b where the recesses 46, 47 are formed, resulting in a larger IR.

The multilayer ceramic capacitors 100, 200, 300, and 400 according to the first to fourth embodiments have been described above. However, the present invention is not limited to the above-described content, and various modifications can be made in accordance with the spirit of the invention.

For example, in the multilayer ceramic capacitors 100, 200, 300, and 400, Ni is used as the main component of the metal component of the base electrode layer 8, but the type of the main component of the metal component is arbitrary, and instead of Ni, for example, Cu, Ag, etc. may also be used.

Further, the extending direction (length direction) of the recesses 6, 7, etc. formed in the capacitive element 1 is also arbitrary, and may be changed from the direction shown in each embodiment. Further, the number of recesses 6, 7, etc. formed in the capacitive element 1 is also arbitrary, and may be increased or decreased from the number shown in each embodiment.

A multilayer ceramic capacitor according to an embodiment of the present invention is as described in the section "Means for Solving the Problems".

In this multilayer ceramic capacitor, it is also preferable that the base electrode layer and the Cu-plated electrode layer are embedded in the recess. In this case, the moisture resistance can be improved by the base electrode layer and the Cu-plated electrode layer embedded in the recess.

It is also preferable that the base electrode layer that is embedded in the recess formed in the first end face is electrically connected to at least one first internal electrode, and that the base electrode layer that is embedded in the recess formed in the second end face is electrically connected to at least one second internal electrode. In this case, the intrusion of moisture from the outside into the first internal electrode and the second internal electrode is suppressed.

When looking at the first end surface from which the first external electrode is removed or the second end surface from which the second external electrode is removed, the recess has a width and a length longer than the width, and the recess has a width and a length longer than the width. It is also preferable that the length direction and the direction in which the first internal electrode exposed on the first end face extends or the direction in which the second internal electrode exposed on the second end face extends are the same direction. In this case, the electrical connection between the first internal electrode and the first external electrode or the electrical connection between the second internal electrode and the second external electrode is not good in the recess. It is carried out.

When looking at a cross section of the capacitive element parallel to the first side surface and the second side surface, the depth direction of the recess and the extending direction of the first internal electrode and the second internal electrode are the same direction. It is also preferable. In this case, the electrical connection between the first internal electrode and the first external electrode or the electrical connection between the second internal electrode and the second external electrode is not good in the recess. It is carried out.

When looking at a cross section of the capacitive element parallel to the first side surface and the second side surface, the depth of the recess is based on the first end surface or the second end surface at the position where the recess is formed. It is also preferable that the thickness is greater than the thickness of the underlying electrode layer. In this case, moisture resistance can be favorably improved.

A first external electrode disposed on the first end surface and a second external electrode disposed on the second end surface extend to the first main surface and the second main surface, respectively. It is also preferable that the depth of the recess is smaller than the length of the folded portion when looking at a cross section of the capacitive element that has the folded portion and is parallel to the first side surface and the second side surface. If the depth of the recess is too large, the lengths of the first internal electrode and the second internal electrode must be shortened to prevent short circuits, which may reduce the capacitance of the multilayer ceramic capacitor. Because there is.

When viewing a cross section of the capacitance element parallel to the first side and the second side, it is also preferable that the base electrode layer that penetrates the recess formed in the first end face is electrically connected to the first internal electrode that is located closest to the first main surface and/or the first internal electrode that is located closest to the second main surface, and that the base electrode layer that penetrates the recess formed in the second end face is electrically connected to the second internal electrode that is located closest to the first main surface and/or the second internal electrode that is located closest to the second main surface. In this case, it is possible to improve the moisture resistance of areas that tend to have low moisture resistance.

It is also preferable that the metal component of the base electrode layer is mainly composed of Ni. In this case, it becomes possible to fire the base electrode layer at the same time as firing the capacitance element and internal electrodes, improving productivity.

It is also preferable that the capacitor further comprises a third internal electrode that is disposed on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, is located inside the capacitance element, and is exposed on the first side and/or the second side, and a third external electrode that is disposed on the first side and/or the second side and is connected to the third internal electrode, thereby forming a three-terminal type capacitor. In this case, a three-terminal type multilayer ceramic capacitor with high moisture resistance and large IR can be obtained.

1... Capacitive element 1A... First main surface 1B... Second main surface 1C... First side surface 1D... Second side surface 1E... First end surface 1F. ...Second end surface 1a...Dielectric layer 2...First internal electrode 3...Second internal electrode 4...First external electrode 4a...Folded portion 5... Second external electrode 5a...Folded portions 6, 7, 26, 27, 36, 37, 46, 47...Concave portion 8...Base electrode layer 9...Cu plating layer 10...Ni plating Layer 11...Sn plating layer 40a, 40b...Third external electrode 44...Third internal electrode

Claims (12)

a capacitance element having a first main surface and a second main surface opposed to each other in a height direction, a first side surface and a second side surface opposed to each other in a width direction perpendicular to the height direction, and a first end surface and a second end surface opposed to each other in a length direction perpendicular to the height direction and the width direction, the capacitance element being formed by stacking a plurality of dielectric layers in the height direction;
a first internal electrode disposed on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, positioned inside the capacitance element, and exposed at the first end surface;
a second internal electrode disposed on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, positioned inside the capacitance element, and exposed at the second end surface;
a first outer electrode disposed on the first end surface and electrically connected to the first inner electrode;
a second external electrode disposed on the second end surface and electrically connected to the second internal electrode,
each of the first external electrode and the second external electrode has a base electrode layer having a metal component and a ceramic component, a Cu-plated electrode layer disposed on the base electrode layer, a Ni-plated electrode layer disposed on the Cu-plated electrode layer, and a Sn-plated electrode layer disposed on the Ni-plated electrode layer;
a recess is formed on each of the first end face and the second end face of the capacitance element, and the base electrode layer and the Cu-plated electrode layer are embedded in the recess;
Multilayer ceramic capacitor. a capacitance element having a first main surface and a second main surface opposed to each other in a height direction, a first side surface and a second side surface opposed to each other in a width direction perpendicular to the height direction, and a first end surface and a second end surface opposed to each other in a length direction perpendicular to the height direction and the width direction, the capacitance element being formed by stacking a plurality of dielectric layers in the height direction;
a first internal electrode disposed on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, positioned inside the capacitance element, and exposed at the first end surface;
a second internal electrode disposed on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, located inside the capacitive element, and exposed to the second end surface;
a first external electrode disposed on the first end surface and electrically connected to the first internal electrode;
a second external electrode disposed on the second end surface and electrically connected to the second internal electrode,
The first external electrode and the second external electrode each include a base electrode layer having a metal component and a ceramic component, a Cu plating electrode layer disposed on the base electrode layer, and the Cu plating electrode layer. comprising a Ni plating electrode layer disposed on the Ni plating electrode layer and a Sn plating electrode layer disposed on the Ni plating electrode layer,
recesses are formed in the first end surface and the second end surface of the capacitive element, respectively, and the base electrode layer enters into the recesses,
the base electrode layer extending into the recess formed on the first end face is electrically connected to at least one of the first internal electrodes,
the base electrode layer that has entered the recess formed in the second end surface and at least one of the second internal electrodes are electrically connected;
Multilayer ceramic capacitor. When looking at the first end surface from which the first external electrode is removed or the second end surface from which the second external electrode is removed,
The recess has a width and a length longer than the width,
The direction of the length of the recess and the direction in which the first internal electrode exposed on the first end face extends, or the direction in which the second internal electrode exposed on the second end face extends, in the same direction,
A multilayer ceramic capacitor according to claim 1 or 2 . When a cross section of the capacitance element parallel to the first side surface and the second side surface is viewed,
a depth direction of the recess and an extension direction of the first internal electrode and the second internal electrode are the same direction;
4. A multilayer ceramic capacitor according to claim 1. When a cross section of the capacitance element parallel to the first side surface and the second side surface is viewed,
The depth of the recess is
the thickness of the base electrode layer is greater than the thickness of the base electrode layer at the position where the recess is formed, based on the first end face or the second end face;
5. A multilayer ceramic capacitor according to claim 1. The first external electrode arranged on the first end face and the second external electrode arranged on the second end face are connected to the first main face and the second main face, respectively. having folded portions each extending to the main surface;
When looking at a cross section of the capacitive element parallel to the first side surface and the second side surface,
The depth of the recess is
smaller than the length of the folded portion;
A multilayer ceramic capacitor according to any one of claims 1 to 5 . When looking at a cross section of the capacitive element parallel to the first side surface and the second side surface,
The base electrode layer that has entered the recess formed in the first end surface, the first internal electrode disposed closest to the first main surface, and/or the first internal electrode disposed closest to the second main surface electrically connected to the first internal electrode disposed near the surface;
The base electrode layer that has entered the recess formed in the second end surface, the second internal electrode that is located closest to the first main surface, and/or the second internal electrode that is located closest to the second main surface. electrically connected to the second internal electrode located near the surface;
A multilayer ceramic capacitor according to any one of claims 1 to 6 . The metal component of the base electrode layer is mainly composed of Ni.
8. A multilayer ceramic capacitor according to claim 1. a third internal electrode disposed on a plurality of dielectric layers arbitrarily selected from the plurality of dielectric layers, positioned inside the capacitance element, and exposed to the first side surface and/or the second side surface;
a third external electrode disposed on the first side surface and/or the second side surface and connected to the third internal electrode;
A three-terminal capacitor is configured.
9. A multilayer ceramic capacitor according to claim 1. A method for manufacturing a multilayer ceramic capacitor according to any one of claims 1 to 9 , comprising:
A process of producing multiple ceramic green sheets,
a step of applying a conductive paste to form an internal electrode in a desired shape on the main surface of a plurality of ceramic green sheets arbitrarily selected from the plurality of ceramic green sheets;
The plurality of ceramic green sheets are laminated and integrated to form a first main surface and a second main surface, a first side surface and a second side surface, and a first end surface and a second end surface. a step of producing a green capacitive element having;
cutting the first end face and the second end face of the green capacitive element to form green recesses in each;
Applying a conductive paste for forming a base electrode layer of an external electrode to the first end surface and the second end surface including the unfired recess, respectively;
The green capacitive element is fired and has a first main surface and a second main surface, a first side surface and a second side surface, a first end surface and a second end surface, and inside thereof, A plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes are laminated, and a recess is formed in each of the first end face and the second end face, and includes the recess. A capacitive element is manufactured, in which the base electrode layer of a first external electrode is formed on the first end face, and the base electrode layer of a second external electrode is formed on the second end face including the recess. process and
forming a Cu plating electrode layer on the base electrode layer;
forming a Ni-plated electrode layer on the Cu-plated electrode layer;
forming a Sn plating electrode layer on the Ni plating electrode layer,
Manufacturing method for multilayer ceramic capacitors. A method for manufacturing a multilayer ceramic capacitor according to any one of claims 1 to 9 , comprising:
A process of producing multiple ceramic green sheets,
applying a release agent in a desired shape to an arbitrarily selected area on the main surface of a ceramic green sheet arbitrarily selected from the plurality of ceramic green sheets;
Applying a conductive paste to form internal electrodes in a desired shape on the main surface of a plurality of ceramic green sheets arbitrarily selected from the plurality of ceramic green sheets and/or on the applied release agent. The process of
The plurality of ceramic green sheets are laminated and integrated to form a first main surface and a second main surface, a first side surface and a second side surface, and a first end surface and a second end surface. a step of producing a green capacitive element having;
Vibration is applied to the unfired capacitive element to partially peel off the laminated ceramic green sheets and the ceramic green sheets in the area where the release agent has been applied, so that the first end face and the second end face are separated. forming unfired recesses on the end faces, respectively;
Applying a conductive paste for forming a base electrode layer of an external electrode to the first end surface and the second end surface including the unfired recess, respectively;
The green capacitive element is fired and has a first main surface and a second main surface, a first side surface and a second side surface, a first end surface and a second end surface, and inside thereof, A plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes are laminated, and a recess is formed in each of the first end face and the second end face, and includes the recess. A capacitive element is manufactured, in which the base electrode layer of a first external electrode is formed on the first end face, and the base electrode layer of a second external electrode is formed on the second end face including the recess. process and
forming a Cu plating electrode layer on the base electrode layer;
forming a Ni-plated electrode layer on the Cu-plated electrode layer;
forming a Sn plating electrode layer on the Ni plating electrode layer,
Manufacturing method for multilayer ceramic capacitors. A method for producing a multilayer ceramic capacitor according to any one of claims 1 to 9 , comprising the steps of:
preparing a plurality of ceramic green sheets;
applying a conductive paste for forming internal electrodes in a desired shape onto main surfaces of a plurality of ceramic green sheets arbitrarily selected from the plurality of ceramic green sheets;
applying a release agent in a desired shape to a main surface of a ceramic green sheet selected from the plurality of ceramic green sheets and/or to an area selected from the conductive paste applied;
stacking and integrating the plurality of ceramic green sheets to produce an unfired capacitive element having first and second main surfaces, first and second side surfaces, and first and second end surfaces;
applying vibration to the unsintered capacitance element to partially peel off the laminated ceramic green sheets at the portions where the release agent is applied, thereby forming unsintered recesses on the first end face and the second end face;
applying a conductive paste for forming a base electrode layer of an external electrode to each of the first end face and the second end face including the unsintered recess;
a step of firing the unsintered capacitance element to produce a capacitance element having first and second main surfaces, first and second side surfaces, and first and second end surfaces, a plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes laminated therein, a recess formed in each of the first end surface and the second end surface, the base electrode layer of a first external electrode formed on the first end surface including the recess, and the base electrode layer of a second external electrode formed on the second end surface including the recess;
forming a Cu-plated electrode layer on the base electrode layer;
forming a Ni-plated electrode layer on the Cu-plated electrode layer;
and forming a Sn-plated electrode layer on the Ni-plated electrode layer.
A method for manufacturing a multilayer ceramic capacitor.

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