Laminated ceramic electronic component

Abstract

The invention provides a laminated ceramic electronic component capable of improving flexural endurance. The present invention is provided with a laminated body (10) and a pair of external electrodes (40) disposed at both ends of the laminated body (10), the external electrodes (40) including a main surface-side external electrode (411A) having a main surface-side base electrode layer (511A) and a main surface-side plating layer (611A) formed above the main surface-side base electrode layer (511A). The main surface-side external electrode (411A) has a recess (510A) recessed toward the laminate (10) side in a cross-sectional view along the lamination direction and the longitudinal direction of the laminate (10), and the main surface-side base electrode layer (511A) has a recess-corresponding region corresponding to the recess (510A) and a peripheral region adjacent to the recess-corresponding region in the longitudinal direction. The metal density of the recess-corresponding region is lower than the metal density of the peripheral region.

Description

Technical Field

[0001] The present invention relates to a multilayer ceramic electronic component. Background Art

[0002] Traditionally, multilayer ceramic capacitors are known as multilayer ceramic electronic components. Generally speaking, a multilayer ceramic capacitor comprises a laminated body in which multiple dielectric layers and internal electrode layers are alternately stacked, and external electrodes provided on both end surfaces of the laminated body. For example, Patent Document 1 discloses a multilayer ceramic capacitor having the aforementioned structure, wherein the external electrodes include a base electrode layer formed by sintering.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2003-243249

[0006] However, in such multilayer ceramic capacitors, when mounted on a substrate, flexural stress generated at the external electrodes is transmitted to the multilayer body, potentially causing cracks in the multilayer body. Therefore, multilayer ceramic capacitors with improved flexural resistance are desired. Summary of the Invention

[0007] Problems to be solved by the invention

[0008] An object of the present invention is to provide a multilayer ceramic electronic component capable of improving flexural resistance.

[0009] Technical solutions to solve problems

[0010] The multilayer ceramic electronic component of the present invention comprises: a multilayer body including a plurality of ceramic layers and a plurality of internal conductor layers alternately stacked in a stacking direction, and including a first main surface and a second main surface opposite to each other in the stacking direction, a first end surface and a second end surface opposite to each other in a longitudinal direction perpendicular to the stacking direction, and a first side surface and a second side surface opposite to each other in a width direction perpendicular to the stacking direction and the longitudinal direction; and a pair of external electrodes separately arranged at two end portions of the multilayer body in the longitudinal direction, the internal conductor layers including a first internal conductor layer led to the first end surface, and a second internal conductor layer led to the second end surface. A second internal conductor layer, the external electrode includes a main surface side external electrode arranged on at least one of the first main surface and the second main surface, the main surface side external electrode has a main surface side base electrode layer, and a main surface side plating layer formed on an upper layer than the main surface side base electrode layer, the main surface side external electrode has a recessed portion recessed toward the stacked body side in a cross-section along the stacking direction and the longitudinal direction, the main surface side base electrode layer has a recess corresponding area corresponding to the recess, and a peripheral area adjacent to the recess corresponding area in the longitudinal direction, the metal density of the recess corresponding area is lower than the metal density of the peripheral area.

[0011] Effects of the Invention

[0012] According to the present invention, a multilayer ceramic electronic component capable of improving flexural resistance can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a perspective view of the appearance of a multilayer ceramic capacitor according to an embodiment.

[0014] Figure 2 yes Figure 1 II-II sectional view.

[0015] Figure 3 yes Figure 2 Sectional view III-III.

[0016] Figure 4A yes Figure 2 IVA-IVA cross-sectional view.

[0017] Figure 4B yes Figure 2 IVB-IVB cross-sectional view.

[0018] Figure 5A yes Figure 2 VA is an enlarged view of the portion indicated by VA, and is a view showing a cross section of the first main surface side external electrode.

[0019] Figure 5B is with Figure 5A It is a corresponding figure and is a figure showing the cross section of the first main surface side external electrode.

[0020] Figure 6A 1 and 2 are views illustrating a method for manufacturing a multilayer ceramic capacitor according to an embodiment, and are views illustrating a step of forming external electrodes on a multilayer body.

[0021] Figure 6B 1 and 2 are views illustrating a method for manufacturing a multilayer ceramic capacitor according to an embodiment, and are views illustrating a step of forming external electrodes on a multilayer body.

[0022] Figure 7A A diagram showing a two-cell multilayer ceramic capacitor.

[0023] Figure 7B A diagram showing a triple-structured multilayer ceramic capacitor.

[0024] Figure 7C A diagram showing a quadruple-structured multilayer ceramic capacitor.

[0025] Description of Reference Numerals

[0026] 1: Multilayer ceramic capacitors (multilayer ceramic electronic components);

[0027] 10: laminate;

[0028] 20: dielectric layer (ceramic layer);

[0029] 30: internal electrode layer (internal conductor layer);

[0030] 31: first internal electrode layer (first internal conductor layer);

[0031] 32: second internal electrode layer (second internal conductor layer);

[0032] 35: floating internal electrode layer (floating internal conductor layer);

[0033] 40: external electrode;

[0034] 400A: 1st end surface side external electrode (end surface side external electrode);

[0035] 400B: Second end surface side external electrode (end surface side external electrode);

[0036] 411A: first main surface side external electrode (main surface side external electrode);

[0037] 411B: first main surface side external electrode (main surface side external electrode);

[0038] 412A: Second main surface side external electrode (main surface side external electrode);

[0039] 412B: second main surface side external electrode (main surface side external electrode);

[0040] 510A: Recessed portion (recessed portion) on the first main surface side;

[0041] 510B: Recessed portion (recessed portion) on the first main surface;

[0042] 511A: first main surface side base electrode layer (main surface side base electrode layer);

[0043] 511B: first main surface side base electrode layer (main surface side base electrode layer);

[0044] 512A: second main surface side base electrode layer (main surface side base electrode layer);

[0045] 512B: second main surface side base electrode layer (main surface side base electrode layer);

[0046] 520A: Second main surface side concave portion (recessed portion);

[0047] 520B: Second main surface side concave portion (recessed portion);

[0048] 550: area corresponding to the concave portion;

[0049] 560: medial peripheral region (peripheral region);

[0050] 570: Outer peripheral area (peripheral area);

[0051] 611A: first main surface side plating layer (main surface side plating layer);

[0052] 611B: first main surface side plating layer (main surface side plating layer);

[0053] 612A: Second main surface side plating layer (main surface side plating layer);

[0054] 612B: Second main surface side plating layer (main surface side plating layer);

[0055] L: length direction;

[0056] T: stacking direction;

[0057] W: width direction;

[0058] LS1: 1st end face;

[0059] LS2: 2nd end face;

[0060] TS1: 1st main surface;

[0061] TS2: 2nd main surface;

[0062] WS1: side 1;

[0063] WS2: Side 2. DETAILED DESCRIPTION

[0064] Hereinafter, a multilayer ceramic capacitor 1 as a multilayer ceramic electronic component according to an embodiment of the present disclosure will be described with reference to the drawings. Figure 1 It is a perspective view of the appearance of a multilayer ceramic capacitor 1 according to the embodiment. Figure 2 yes Figure 1 II-II sectional view. Figure 3 yes Figure 2 Sectional view III-III. Figure 4A yes Figure 2 IVA-IVA cross-sectional view. Figure 4B yes Figure 2 IVB-IVB cross-sectional view.

[0065] like Figure 1 As shown, the multilayer ceramic capacitor 1 according to the embodiment has a substantially rectangular parallelepiped shape. The multilayer ceramic capacitor 1 includes a substantially rectangular parallelepiped laminate 10 and a pair of external electrodes 40 disposed at both ends of the laminate 10 so as to be spaced apart from each other.

[0066] exist Figure 1 In FIG. 1 , arrow T indicates the stacking direction of the multilayer ceramic capacitor 1 and the multilayer body 10. The stacking direction T is also the thickness direction and height direction of the multilayer ceramic capacitor 1 and the multilayer body 10. Figure 1 In FIG. 1 , arrow L indicates the longitudinal direction of the multilayer ceramic capacitor 1 and the multilayer body 10 perpendicular to the stacking direction T. Figure 1 In FIG, arrow W indicates the width direction of the multilayer ceramic capacitor 1 and the laminate 10 , which is perpendicular to the lamination direction T and the longitudinal direction L. The pair of external electrodes 40 are respectively arranged at one end and the other end of the laminate 10 in the longitudinal direction L.

[0067] exist Figures 1 to 4B In FIG, an XYZ orthogonal coordinate system is shown. The length direction L of the multilayer ceramic capacitor 1 and the multilayer body 10 corresponds to the X direction. The width direction W of the multilayer ceramic capacitor 1 and the multilayer body 10 corresponds to the Y direction. The stacking direction T of the multilayer ceramic capacitor 1 and the multilayer body 10 corresponds to the Z direction. Here, Figure 2 The section shown is also referred to as the LT section. Figure 3 The cross section shown is also referred to as the WT cross section. Figure 4A as well as Figure 4B The cross section shown is also referred to as the LW cross section.

[0068] like Figures 1 to 4BAs shown, the stack 10 includes a first main surface TS1 and a second main surface TS2 opposite to each other in the stacking direction T, a first end surface LS1 and a second end surface LS2 opposite to each other in the length direction L perpendicular to the stacking direction T, and a first side surface WS1 and a second side surface WS2 opposite to each other in the width direction W perpendicular to the stacking direction T and the length direction L.

[0069] like Figure 1 As shown, the laminate 10 has a generally rectangular parallelepiped shape. Furthermore, the dimension of the laminate 10 in the longitudinal direction L is not necessarily longer than the dimension in the width direction W. The corners and ridges of the laminate 10 are preferably rounded. A corner is where three surfaces of the laminate intersect, and a ridge is where two surfaces of the laminate intersect. Furthermore, concavities and convexities may be formed on part or all of the surface constituting the laminate 10.

[0070] The dimensions of the laminate 10 are not particularly limited, but if the dimension in the longitudinal direction L of the laminate 10 is defined as the L dimension, the L dimension is preferably 0.2 mm or more and 10 mm or less. Furthermore, if the dimension in the stacking direction T of the laminate 10 is defined as the T dimension, the T dimension is preferably 0.05 mm or more and 10 mm or less. Furthermore, if the dimension in the width direction W of the laminate 10 is defined as the W dimension, the W dimension is preferably 0.1 mm or more and 10 mm or less.

[0071] like Figure 2 as well as Figure 3 As shown, the laminate 10 includes an inner layer portion 11 , and a first main surface side outer layer portion 12 and a second main surface side outer layer portion 13 arranged in the lamination direction T so as to sandwich the inner layer portion 11 .

[0072] The inner layer portion 11 includes a plurality of dielectric layers 20 as ceramic layers and a plurality of internal electrode layers 30 as internal conductor layers, alternately stacked in a stacking direction T. The inner layer portion 11 extends from the internal electrode layer 30 located closest to the first main surface TS1 to the internal electrode layer 30 located closest to the second main surface TS2 in the stacking direction T. In the inner layer portion 11, the plurality of internal electrode layers 30 are arranged so as to face each other with the dielectric layer 20 interposed therebetween. The inner layer portion 11 is a portion that generates electrostatic capacitance and essentially functions as a capacitor.

[0073] The plurality of dielectric layers 20 are formed of a dielectric material. For example, the dielectric material may be a dielectric ceramic containing BaTiO3, CaTiO3, SrTiO3, or CaZrO3. Furthermore, the dielectric material may be a material containing these main components with minor components such as Mn compounds, Fe compounds, Cr compounds, Co compounds, and Ni compounds added thereto. The dielectric material is particularly preferably a material containing BaTiO3 as a main component.

[0074] The thickness of the dielectric layer 20 is preferably not less than 0.2 μm and not more than 15 μm. The number of dielectric layers 20 stacked is preferably not less than 10 and not more than 1200. The number of dielectric layers 20 is the sum of the number of dielectric layers 20 in the inner layer portion 11 and the number of dielectric layers 20 in each of the first main surface-side outer layer portion 12 and the second main surface-side outer layer portion 13.

[0075] The multiple internal electrode layers 30 include multiple first internal electrode layers 31 serving as multiple first internal conductor layers and multiple second internal electrode layers 32 serving as multiple second internal conductor layers. The first internal electrode layers 31 and the second internal electrode layers 32 are alternately arranged in the stacking direction T, with the dielectric layer 20 interposed therebetween. The first internal electrode layers 31 extend to the first end surface LS1. The second internal electrode layers 32 extend to the second end surface LS2. In the following description, when it is not necessary to distinguish between the first internal electrode layers 31 and the second internal electrode layers 32, the first internal electrode layers 31 and the second internal electrode layers 32 may be collectively referred to as the internal electrode layers 30.

[0076] like Figure 4A As shown, the first internal electrode layer 31 includes a first opposing portion 31A and a first lead portion 31B. The first opposing portion 31A is a region that faces the second internal electrode layer 32 with the dielectric layer 20 interposed therebetween and is located within the laminate 10. The first lead portion 31B extends from the first opposing portion 31A to the first end surface LS1 and is exposed on the first end surface LS1.

[0077] like Figure 4B As shown, the second internal electrode layer 32 includes a second opposing portion 32A and a second lead portion 32B. The second opposing portion 32A is a region that faces the first internal electrode layer 31 with the dielectric layer 20 interposed therebetween and is located within the laminate 10. The second lead portion 32B extends from the second opposing portion 32A to the second end surface LS2 and is exposed on the second end surface LS2.

[0078] In the embodiment, the first opposing portion 31A and the second opposing portion 32A face each other via the dielectric layer 20 , thereby forming capacitance and exhibiting capacitor characteristics.

[0079] The shapes of the first opposing portion 31A and the second opposing portion 32A are not particularly limited, but are preferably rectangular. However, the corners of the rectangular shape may be rounded or angled. The shapes of the first lead portion 31B and the second lead portion 32B are not particularly limited, but are preferably rectangular. However, the corners of the rectangular shape may be rounded or angled.

[0080] The first opposing portion 31A and the first lead portion 31B may have the same dimension in the width direction W, or one of them may be smaller. The second opposing portion 32A and the second lead portion 32B may have the same dimension in the width direction W, or one of them may be smaller.

[0081] The first internal electrode layer 31 and the second internal electrode layer 32 are formed of a suitable conductive material such as a metal such as Ni, Cu, Ag, Pd, or Au, or an alloy containing at least one of these metals. When an alloy is used, the first internal electrode layer 31 and the second internal electrode layer 32 may be formed of, for example, an Ag-Pd alloy.

[0082] The thickness of each of the first internal electrode layer 31 and the second internal electrode layer 32 is preferably 0.2 μm to 2.0 μm, for example. The total number of the first internal electrode layers 31 and the second internal electrode layers 32 is preferably 10 to 1000.

[0083] like Figure 2 as well as Figure 3 As shown, the first principal surface-side outer layer portion 12 is located on the first principal surface TS1 side of the laminate 10. The first principal surface-side outer layer portion 12 is a collection of multiple dielectric layers 20 located between the first principal surface TS1 and the internal electrode layer 30 closest to the first principal surface TS1. On the other hand, the second principal surface-side outer layer portion 13 is located on the second principal surface TS2 side of the laminate 10. The second principal surface-side outer layer portion 13 is a collection of multiple dielectric layers 20 located between the second principal surface TS2 and the internal electrode layer 30 closest to the second principal surface TS2. The dielectric layers 20 used in both the first principal surface-side outer layer portion 12 and the second principal surface-side outer layer portion 13 can be the same as the dielectric layers 20 used in the internal layer portion 11.

[0084] Furthermore, the laminate 10 includes an opposing electrode portion 11E. The opposing electrode portion 11E is a portion where the first opposing portion 31A of the first internal electrode layer 31 and the second opposing portion 32A of the second internal electrode layer 32 face each other. The opposing electrode portion 11E is configured as a portion of the inner layer portion 11. Figure 4A as well as Figure 4B ] shows the range of the opposing electrode portion 11E in the width direction W and the length direction L. The opposing electrode portion 11E is also referred to as a capacitor effective portion.

[0085] In addition, the stacked body 10 has a side outer layer portion. The side outer layer portion has a first side outer layer portion WG1 and a second side outer layer portion WG2. The first side outer layer portion WG1 is a portion including the dielectric layer 20 located between the opposing electrode portion 11E and the first side WS1. The second side outer layer portion WG2 is a portion including the dielectric layer 20 located between the opposing electrode portion 11E and the second side WS2. Figure 3 、 Figure 4A as well as Figure 4B : shows the range of the first side outer layer portion WG1 and the second side outer layer portion WG2 in the width direction W. In addition, the side outer layer portion is also called a W gap or a side gap.

[0086] In addition, the stacked body 10 has an end face side outer layer portion. The end face side outer layer portion has a first end face side outer layer portion LG1 and a second end face side outer layer portion LG2. The first end face side outer layer portion LG1 is a portion including the dielectric layer 20 and the first lead portion 31B located between the opposing electrode portion 11E and the first end face LS1. That is, the first end face side outer layer portion LG1 is a collection of portions of the plurality of dielectric layers 20 on the first end face LS1 side and the plurality of first lead portions 31B. The second end face side outer layer portion LG2 is a portion including the dielectric layer 20 and the second lead portion 32B located between the opposing electrode portion 11E and the second end face LS2. That is, the second end face side outer layer portion LG2 is a collection of portions of the plurality of dielectric layers 20 on the second end face LS2 side and the plurality of second lead portions 32B. In Figure 2 、 Figure 4A as well as Figure 4B : shows the range of the first end surface side outer layer portion LG1 and the second end surface side outer layer portion LG2 in the longitudinal direction L. In addition, the end surface side outer layer portion is also called an L gap or an end gap.

[0087] like Figure 1 as well as Figure 2 As shown, the external electrode 40 includes a first external electrode 40A arranged on the first end surface LS1 side of the stacked body 10 and a second external electrode 40B arranged on the second end surface LS2 side of the stacked body 10 .

[0088] The first external electrode 40A and the second external electrode 40B have the same basic structure. Furthermore, the first external electrode 40A and the second external electrode 40B have shapes that are substantially plane-symmetrical with respect to a WT cross-section taken at the center in the longitudinal direction L of the multilayer ceramic capacitor 1. Therefore, in the following description, when there is no need to distinguish between the first external electrode 40A and the second external electrode 40B, the first external electrode 40A and the second external electrode 40B may be collectively referred to as the external electrode 40.

[0089] The first external electrode 40A is arranged on the first end surface LS1. The first external electrode 40A contacts the first lead portion 31B of each of the plurality of first internal electrode layers 31 exposed on the first end surface LS1. Thus, the first external electrode 40A is electrically connected to the plurality of first internal electrode layers 31. The first external electrode 40A may also be arranged on a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2. In the embodiment, the first external electrode 40A is formed to extend from the first end surface LS1 to a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2.

[0090] The second external electrode 40B is arranged on the second end surface LS2. The second external electrode 40B contacts the second lead portion 32B of each of the plurality of second internal electrode layers 32 exposed on the second end surface LS2. Thus, the second external electrode 40B is electrically connected to the plurality of second internal electrode layers 32. The second external electrode 40B may also be arranged on a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2. In the embodiment, the second external electrode 40B is formed to extend from the second end surface LS2 to a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2.

[0091] As described above, within the laminate 10, the first opposing portion 31A of the first internal electrode layer 31 and the second opposing portion 32A of the second internal electrode layer 32 oppose each other via the dielectric layer 20, thereby forming a capacitor. Consequently, capacitor characteristics are exhibited between the first external electrode 40A connected to the first internal electrode layer 31 and the second external electrode 40B connected to the second internal electrode layer 32.

[0092] like Figure 2 、 Figure 4A as well as Figure 4B As shown, the first external electrode 40A includes a first foundation electrode layer 50A and a first plating layer 60A disposed on the first foundation electrode layer 50A. The second external electrode 40B includes a second foundation electrode layer 50B and a second plating layer 60B disposed on the second foundation electrode layer 50B.

[0093] The first foundation electrode layer 50A is disposed on the first end surface LS1. The first foundation electrode layer 50A is connected to the first lead portions 31B of each of the plurality of first internal electrode layers 31 exposed on the first end surface LS1. In the embodiment, the first foundation electrode layer 50A is formed so as to extend from the first end surface LS1 to a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2.

[0094] The second foundation electrode layer 50B is disposed on the second end surface LS2. The second foundation electrode layer 50B contacts the second lead portions 32B of each of the plurality of second internal electrode layers 32 exposed on the second end surface LS2. In the embodiment, the second foundation electrode layer 50B is formed so as to extend from the second end surface LS2 to a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2.

[0095] The first and second base electrode layers 50A and 50B of the embodiment are sintered layers. The sintered layers preferably contain either a metal component and a glass component or a ceramic component, or both. The metal component, for example, includes at least one selected from Cu, Ni, Ag, Pd, an Ag-Pd alloy, Au, and the like. The glass component, for example, includes at least one selected from B, Si, Ba, Mg, Al, Li, and the like. The ceramic component may be the same or a different type of ceramic material as the dielectric layer 20. For example, the ceramic component includes at least one selected from BaTiO3, CaTiO3, (Ba,Ca)TiO3, SrTiO3, CaZrO3, and the like.

[0096] The sintered layer is, for example, a sintered layer obtained by applying a conductive paste containing glass and metal to the laminate 10 and sintering it. The sintered layer can be formed by simultaneously sintering the raw materials of the laminate 10 having multiple internal electrode layers and dielectric layers, that is, the laminated pieces before sintering, and the conductive paste applied to the laminated pieces. Alternatively, it can be formed by sintering the laminate 10 to obtain the laminate 10, and then applying a conductive paste to the laminate 10 and sintering it. In addition, in the case of the above-mentioned structure, the sintered layer is preferably formed by sintering a material to which a ceramic material is added instead of a glass component. In this case, it is particularly preferred to use a ceramic material of the same type as the dielectric layer 20 as the added ceramic material. In addition, the sintered layer can also be a plurality of layers.

[0097] The thickness of the first foundation electrode layer 50A located on the first end surface LS1 in the longitudinal direction L is preferably about 2 μm or more and 220 μm or less at the center portion in the stacking direction T and the width direction W of the first foundation electrode layer 50A.

[0098] The thickness of the second foundation electrode layer 50B located on the second end surface LS2 in the longitudinal direction L is preferably about 2 μm or more and 220 μm or less at the center portion in the stacking direction T and the width direction W of the second foundation electrode layer 50B.

[0099] In the case where the first base electrode layer 50A is also provided on a portion of at least one of the first main surface TS1 or the second main surface TS2, the thickness of the first base electrode layer 50A provided on the portion corresponding to the stacking direction T is preferably greater than 3 μm and less than 40 μm at the central portion of the first base electrode layer 50A provided on the portion in the length direction L and the width direction W.

[0100] When the first base electrode layer 50A is also provided on a portion of at least one surface of the first side surface WS1 or the second side surface WS2, the thickness of the first base electrode layer 50A provided on the portion corresponding to the width direction W is preferably greater than 3 μm and less than 40 μm at the center portion in the length direction L and the stacking direction T of the first base electrode layer 50A provided on the portion.

[0101] In the case where a second base electrode layer 50B is also provided on a portion of at least one of the first main surface TS1 or the second main surface TS2, the thickness of the second base electrode layer 50B provided on the portion corresponding to the stacking direction T is preferably greater than 3 μm and less than 40 μm at the center portion in the length direction L and the width direction W of the second base electrode layer 50B provided on the portion.

[0102] In the case where a second base electrode layer 50B is also provided on a portion of at least one surface of the first side surface WS1 or the second side surface WS2, the thickness of the second base electrode layer 50B provided on the portion corresponding to the width direction W is preferably greater than 3 μm and less than 40 μm at the center portion in the length direction L and the stacking direction T of the second base electrode layer 50B provided on the portion.

[0103] The first plating layer 60A is arranged to cover the first foundation electrode layer 50A.

[0104] The second plating layer 60B is arranged to cover the second foundation electrode layer 50B.

[0105] The first plating layer 60A and the second plating layer 60B may include, for example, at least one selected from Cu, Ni, Sn, Ag, Pd, an Ag-Pd alloy, Au, etc. The first plating layer 60A and the second plating layer 60B may each be formed of multiple layers. The first plating layer 60A and the second plating layer 60B preferably have a two-layer structure in which a Sn plating layer is formed on a Ni plating layer.

[0106] The first plating layer 60A is arranged to cover the first base electrode layer 50A. In the embodiment, the first plating layer 60A includes a first Ni plating layer 61A and a first Sn plating layer 62A located on the first Ni plating layer 61A.

[0107] The second plating layer 60B is arranged to cover the second base electrode layer 50B. In the embodiment, the second plating layer 60B includes a second Ni plating layer 61B and a second Sn plating layer 62B located on the second Ni plating layer 61B.

[0108] The Ni plating layer prevents the first and second base electrode layers 50A and 50B from being corroded by solder during assembly of the multilayer ceramic capacitor 1. Furthermore, the Sn plating layer improves solder wettability during assembly of the multilayer ceramic capacitor 1. This facilitates assembly of the multilayer ceramic capacitor 1. The thickness of each of the first Ni plating layer 61A, the first Sn plating layer 62A, the second Ni plating layer 61B, and the second Sn plating layer 62B is preferably 1 μm or more and 15 μm or less.

[0109] The above is the basic structure of the multilayer ceramic capacitor 1 according to the embodiment. Furthermore, if the lengthwise dimension of the multilayer ceramic capacitor 1, including the multilayer body 10 and the external electrodes 40, is defined as the L dimension, then the L dimension is preferably 0.2 mm to 10 mm. Furthermore, if the length of the multilayer ceramic capacitor 1 in the stacking direction is defined as the T dimension, then the T dimension is preferably 0.05 mm to 10 mm. Furthermore, if the widthwise dimension of the multilayer ceramic capacitor 1 is defined as the W dimension, then the W dimension is preferably 0.1 mm to 10 mm.

[0110] The multilayer ceramic capacitor 1 of the embodiment having the above-described basic structure has the following features in the external electrodes 40 , namely, the first external electrode 40A and the second external electrode 40B.

[0111] The external electrode 40 of the embodiment includes a main surface side external electrode arranged on at least one of the first main surface TS1 and the second main surface TS2. In detail, as described above, the first external electrode 40A of the embodiment is arranged on the first end surface LS1 and is formed to extend from the first end surface LS1 to a portion of the first main surface TS1 and a portion of the second main surface TS2 and a portion of the first side surface WS1 and a portion of the second side surface WS2. That is, the first external electrode 40A of the embodiment is as follows. Figure 2As shown, the first end surface side external electrode 400A as the end surface side external electrode arranged on the first end surface LS1, the first main surface side external electrode 411A as the main surface side external electrode arranged on the first main surface TS1, and the second main surface side external electrode 412A as the main surface side external electrode arranged on the second main surface TS2, and as shown Figure 4A as well as Figure 4B As shown, the first side surface side external electrode 421A is arranged on the first side surface WS1 and the second side surface side external electrode 422A is arranged on the second side surface WS2 .

[0112] As described above, the first external electrode 40A includes a first base electrode layer 50A and a first plating layer 60A disposed on the first base electrode layer 50A. Furthermore, in the embodiment, the first base electrode layer 50A is formed so as to extend from the first end surface LS1 to a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2, and the first plating layer 60A is disposed so as to cover the first base electrode layer 50A.

[0113] That is, Figure 2 As shown, the first end-face-side external electrode 400A of the embodiment includes a first end-face-side base electrode layer 500A disposed on the first end-face LS1 and a first end-face-side plating layer 600A formed above the first end-face-side base electrode layer 500A. The first end-face-side base electrode layer 500A is a portion of the first base electrode layer 50A. The first end-face-side plating layer 600A is a portion of the first plating layer 60A and includes a first Ni plating layer 61A and a first Sn plating layer 62A formed on the first Ni plating layer 61A.

[0114] like Figure 2 As shown, the first main surface side external electrode 411A of the embodiment includes a first main surface side base electrode layer 511A as a main surface side base electrode layer arranged on the first main surface TS1, and a first main surface side plating layer 611A as a main surface side plating layer formed above the first main surface side base electrode layer 511A. The first main surface side base electrode layer 511A is part of the first base electrode layer 50A. The first main surface side plating layer 611A is part of the first plating layer 60A and includes a first Ni plating layer 61A and a first Sn plating layer 62A formed on the first Ni plating layer 61A.

[0115] like Figure 2As shown, the second main surface side external electrode 412A of the embodiment includes a second main surface side base electrode layer 512A as a main surface side base electrode layer arranged on the second main surface TS2, and a second main surface side plating layer 612A as a main surface side plating layer formed above the second main surface side base electrode layer 512A. The second main surface side base electrode layer 512A is part of the first base electrode layer 50A. The second main surface side plating layer 612A is part of the first plating layer 60A and includes a first Ni plating layer 61A and a first Sn plating layer 62A on the first Ni plating layer 61A.

[0116] like Figure 4A as well as Figure 4B As shown, the first-side-side external electrode 421A of the embodiment includes a first-side-side base electrode layer 521A disposed on the first side surface WS1 and a first-side-side plating layer 621A formed above the first-side-side base electrode layer 521A. The first-side-side base electrode layer 521A is part of the first base electrode layer 50A. The first-side-side plating layer 621A is part of the first plating layer 60A and includes a first Ni plating layer 61A and a first Sn plating layer 62A formed on the first Ni plating layer 61A.

[0117] like Figure 4A as well as Figure 4B As shown, the second-side external electrode 422A of the embodiment includes a second-side base electrode layer 522A disposed on the second side surface WS2 and a second-side plating layer 622A formed above the second-side base electrode layer 522A. The second-side base electrode layer 522A is part of the first base electrode layer 50A. The second-side plating layer 622A is part of the first plating layer 60A and includes a first Ni plating layer 61A and a first Sn plating layer 62A on the first Ni plating layer 61A.

[0118] The thickness of each of the first Ni plating layer 61A and the first Sn plating layer 62A of the first main surface plating layer 611A, the second main surface plating layer 612A, the first side surface plating layer 621A, and the second side surface plating layer 622A is preferably 1 μm or more and 4 μm or less.

[0119] As described above, the second external electrode 40B of the embodiment is arranged on the second end surface LS2 and is formed to extend from the second end surface LS2 to a portion of the first main surface TS1 and a portion of the second main surface TS2 and a portion of the first side surface WS1 and a portion of the second side surface WS2. That is, the second external electrode 40B of the embodiment is as follows. Figure 2As shown, it includes a second end surface side external electrode 400B as an end surface side external electrode arranged on the first end surface LS1, a first main surface side external electrode 411B as a main surface side external electrode arranged on the first main surface TS1, and a second main surface side external electrode 412B as a main surface side external electrode arranged on the second main surface TS2, and as shown Figure 4A as well as Figure 4B As shown, the first side surface side external electrode 421B is arranged on the first side surface WS1 and the second side surface side external electrode 422B is arranged on the second side surface WS2 .

[0120] As described above, the second external electrode 40B includes a second base electrode layer 50B and a second plating layer 60B disposed on the second base electrode layer 50B. Furthermore, in the embodiment, the second base electrode layer 50B is formed so as to extend from the second end surface LS2 to a portion of the first main surface TS1, a portion of the second main surface TS2, a portion of the first side surface WS1, and a portion of the second side surface WS2, and the second plating layer 60B is disposed so as to cover the second base electrode layer 50B.

[0121] That is, Figure 2 As shown, the second end face side external electrode 400B of the embodiment includes a second end face side base electrode layer 500B disposed on the second end face LS2 and a second end face side plating layer 600B formed above the second end face side base electrode layer 500B. The second end face side base electrode layer 500B is a portion of the second base electrode layer 50B. The second end face side plating layer 600B is a portion of the second plating layer 60B and includes a second Ni plating layer 61B and a second Sn plating layer 62B formed on the second Ni plating layer 61B.

[0122] like Figure 2 As shown, the first main surface side external electrode 411B of the embodiment includes a first main surface side base electrode layer 511B as a main surface side base electrode layer arranged on the first main surface TS1, and a first main surface side plating layer 611B as a main surface side plating layer formed above the first main surface side base electrode layer 511B. The first main surface side base electrode layer 511B is part of the second base electrode layer 50B. The first main surface side plating layer 611B is part of the second plating layer 60B and includes a second Ni plating layer 61B and a second Sn plating layer 62B formed on the second Ni plating layer 61B.

[0123] like Figure 2As shown, the second main surface side external electrode 412B of the embodiment includes a second main surface side base electrode layer 512B as a main surface side base electrode layer arranged on the second main surface TS2, and a second main surface side plating layer 612B as a main surface side plating layer formed above the second main surface side base electrode layer 512B. The second main surface side base electrode layer 512B is part of the second base electrode layer 50B. The second main surface side plating layer 612B is part of the second plating layer 60B and includes a second Ni plating layer 61B and a second Sn plating layer 62B on the second Ni plating layer 61B.

[0124] like Figure 4A as well as Figure 4B As shown, the first-side surface external electrode 421B of the embodiment includes a first-side surface base electrode layer 521B disposed on the first side surface WS1 and a first-side surface plating layer 621B formed above the first-side surface base electrode layer 521B. The first-side surface base electrode layer 521B is part of the second base electrode layer 50B. The first-side surface plating layer 621B is part of the second plating layer 60B and includes a second Ni plating layer 61B and a second Sn plating layer 62B on the second Ni plating layer 61B.

[0125] like Figure 4A as well as Figure 4B As shown, the second-side external electrode 422B of the embodiment includes a second-side base electrode layer 522B disposed on the second side surface WS2 and a second-side plating layer 622B formed above the second-side base electrode layer 522B. The second-side base electrode layer 522B is part of the second base electrode layer 50B. The second-side plating layer 622B is part of the second plating layer 60B and includes a second Ni plating layer 61B and a second Sn plating layer 62B on the second Ni plating layer 61B.

[0126] The thickness of the second Ni plating layer 61B and the second Sn plating layer 62B of the first main surface plating layer 611B, the second main surface plating layer 612B, the first side surface plating layer 621B, and the second side surface plating layer 622B is preferably, for example, 1 μm or more and 4 μm or less.

[0127] Figure 2 The LT cross section of the multilayer ceramic capacitor 1 and the laminate 10 along the stacking direction T and the longitudinal direction L is shown. In this LT cross section, the first main surface side external electrode 411A of the first external electrode 40A has a first main surface side recessed portion 510A as a recessed portion that is recessed toward the laminate 10 side. The first main surface side recessed portion 510A is formed on the surface of the first main surface side external electrode 411A. The first main surface side recessed portion 510A has a width direction W that is perpendicular to the LT cross section. Figure 2 The first principal surface side recess 510A may be formed to extend across the entire length of the first principal surface side external electrode 411A along the width direction W. The first principal surface side recess 510A is disposed approximately near the center of the first principal surface side external electrode 411A in the longitudinal direction L.

[0128] like Figure 2 As shown, in the LT cross-section, the second main surface side external electrode 412A of the first external electrode 40A has a second main surface side recessed portion 520A as a recessed portion that is recessed toward the laminate 10 side. The second main surface side recessed portion 520A is formed on the surface of the second main surface side external electrode 412A. The second main surface side recessed portion 520A has a width direction W that is perpendicular to the LT cross-section. Figure 2 The second main surface side recess 520A may be formed to extend across the entire length of the second main surface side external electrode 412A along the width direction W. The second main surface side recess 520A is disposed approximately near the center of the second main surface side external electrode 412A in the longitudinal direction L.

[0129] like Figure 2 As shown, in the LT cross-section, the first main surface side external electrode 411B of the second external electrode 40B has a first main surface side recessed portion 510B as a recessed portion that is recessed toward the laminate 10 side. The first main surface side recessed portion 510B is formed on the surface of the first main surface side external electrode 411B. The first main surface side recessed portion 510B has a width direction W that is perpendicular to the LT cross-section. Figure 2 The first principal surface side recess 510B may be formed to extend across the entire length of the first principal surface side external electrode 411B along the width direction W. The first principal surface side recess 510B is disposed approximately near the center of the first principal surface side external electrode 411B in the longitudinal direction L.

[0130] like Figure 2 As shown, in the LT cross-section, the second main surface side external electrode 412B of the second external electrode 40B has a second main surface side recessed portion 520B as a recessed portion that is recessed toward the laminate 10 side. The second main surface side recessed portion 520B is formed on the surface of the second main surface side external electrode 412B. The second main surface side recessed portion 520B has a width direction W that is perpendicular to the LT cross-section. Figure 2 The second main surface side recess 520B may be formed to extend in the front-to-back direction of the paper. The second main surface side recess 520B may also be formed to extend over the entire length of the second main surface side external electrode 412B along the width direction W. The second main surface side recess 520B is arranged approximately near the center of the second main surface side external electrode 412B in the longitudinal direction L.

[0131] Figure 4A as well as Figure 4BThe LW cross section of the multilayer ceramic capacitor 1 and the laminate 10 along the length direction L and the width direction W is shown. In this LW cross section, the first side surface external electrode 421A of the first external electrode 40A has a first side surface recessed portion 530A as a recessed portion that is recessed toward the laminate 10 side. The first side surface recessed portion 530A is formed on the surface of the first side surface external electrode 421A. The first side surface recessed portion 530A has a longitudinal direction T perpendicular to the LW cross section, i.e., the longitudinal direction T. Figure 4A as well as Figure 4B The first side surface recess 530A may be formed to extend in the front-to-back direction of the paper. The first side surface recess 530A may also be formed to span the entire length of the first side surface external electrode 421A along the stacking direction T. The first side surface recess 530A is disposed approximately near the center of the first side surface external electrode 421A in the longitudinal direction L. The first side surface recess 530A may communicate with either or both of the first main surface recess 510A and the second main surface recess 520A described above.

[0132] like Figure 4A as well as Figure 4B As shown, in the LW cross-sectional view, the second side surface external electrode 422A of the first external electrode 40A has a second side surface concave portion 540A as a concave portion that is recessed toward the stacked body 10. The second side surface concave portion 540A is formed on the surface of the second side surface external electrode 422A. The second side surface concave portion 540A has a stacking direction T perpendicular to the LW cross-sectional view. Figure 4A as well as Figure 4B The second side surface recess 540A may be formed to extend in the front-to-back direction of the paper. The second side surface recess 540A may also be formed to extend across the entire length of the second side surface external electrode 422A along the stacking direction T. The second side surface recess 540A is disposed approximately near the center of the second side surface external electrode 422A in the longitudinal direction L. The second side surface recess 540A may communicate with either or both of the first main surface recess 510A and the second main surface recess 520A described above.

[0133] like Figure 4A as well as Figure 4B As shown, in the LW cross-sectional view, the first side surface external electrode 421B of the second external electrode 40B has a first side surface concave portion 530B as a concave portion that is recessed toward the stacked body 10. The first side surface concave portion 530B is formed on the surface of the first side surface external electrode 421B. The first side surface concave portion 530B has a stacking direction T perpendicular to the LW cross-sectional view. Figure 4A as well as Figure 4BThe first side surface recess 530B may be formed to extend in the front-to-back direction of the paper. The first side surface recess 530B may also be formed to extend across the entire length of the first side surface external electrode 421B along the stacking direction T. The first side surface recess 530B is disposed approximately near the center of the first side surface external electrode 421B in the longitudinal direction L. The first side surface recess 530B may communicate with either or both of the first main surface recess 510B and the second main surface recess 520B described above.

[0134] like Figure 4A as well as Figure 4B As shown, in the LW cross-sectional view, the second side surface external electrode 422B of the second external electrode 40B has a second side surface concave portion 540B as a concave portion that is recessed toward the stacked body 10. The second side surface concave portion 540B is formed on the surface of the second side surface external electrode 422B. The second side surface concave portion 540B has a stacking direction T perpendicular to the LW cross-sectional view. Figure 4A as well as Figure 4B The second side surface recess 540B may be formed to extend in the front-to-back direction of the paper. The second side surface recess 540B may also be formed to extend across the entire length of the second side surface external electrode 422B along the stacking direction T. The second side surface recess 540B is disposed approximately near the center of the second side surface external electrode 422B in the longitudinal direction L. The second side surface recess 540B may communicate with either or both of the first main surface recess 510B and the second main surface recess 520B described above.

[0135] The first principal surface-side external electrode 411A and the second principal surface-side external electrode 412A of the first external electrode 40A, and the first principal surface-side external electrode 411B and the second principal surface-side external electrode 412B of the second external electrode 40B have the same structure. Furthermore, the first side surface-side external electrode 421A and the second side surface-side external electrode 422A of the first external electrode 40A, and the first side surface-side external electrode 421B and the second side surface-side external electrode 422B of the second external electrode 40B also have the same structure as the four principal surface-side external electrodes 411A, 412A, 411B, and 412B described above.

[0136] The first main surface side recessed portions 510A and the second main surface side recessed portions 520A of the first external electrode 40A and the first main surface side recessed portions 510B and the second main surface side recessed portions 520B of the second external electrode 40B have the same structure. Furthermore, the first side surface side recessed portions 530A and the second side surface side recessed portions 540A of the first external electrode 40A and the first side surface side recessed portions 530B and the second side surface side recessed portions 540B of the second external electrode 40B also have the same structure as the four main surface side recessed portions 510A, 520A, 510B, and 520B described above.

[0137] Therefore, as representatives of the main surface side external electrodes and main surface side recesses at these four locations and the side surface external electrodes and side surface recesses at these four locations, the first main surface side external electrode 411A and the first main surface side recess 510A of the first external electrode 40A are described below, thereby serving as an explanation of the main surface side external electrodes and main surface side recesses at the four locations and the side surface external electrodes and side surface recesses at the four locations.

[0138] Furthermore, the first principal surface-side external electrode 411A of the first external electrode 40A corresponds to the second principal surface-side external electrode 412A, the first side surface-side external electrode 421A, and the second side surface-side external electrode 422A of the first external electrode 40A, and the first principal surface-side external electrode 411B, the second principal surface-side external electrode 412B, the first side surface-side external electrode 421B, and the second side surface-side external electrode 422B of the second external electrode 40B. The first principal surface-side recess 510A of the first external electrode 40A corresponds to the second principal surface-side recess 520A, the first side surface-side recess 530A, and the second side surface-side recess 540A of the first external electrode 40A, and the first principal surface-side recess 510B, the second principal surface-side recess 520B, the first side surface-side recess 530B, and the second side surface-side recess 540B of the second external electrode 40B.

[0139] The first base electrode layer 50A and the first plating layer 60A of the first external electrode 40A correspond to the second base electrode layer 50B and the second plating layer 60B of the second external electrode 40B. The first Ni plating layer 61A and the first Sn plating layer 62A of the first plating layer 60A of the first external electrode 40A correspond to the second Ni plating layer 61B and the second Sn plating layer 62B of the second plating layer 60B of the second external electrode 40B.

[0140] Figure 5A yes Figure 2 VA is an enlarged view of the portion indicated by , and is an LT cross-sectional view showing the first principal surface side external electrode 411A of the first external electrode 40A. Figure 5B is with Figure 5A The corresponding figure shows the outer shape of the LT cross section of the first main surface side external electrode 411A of the first external electrode 40A. Figure 5A as well as Figure 5B Shown in Figures 1 to 4B The same XYZ orthogonal coordinate system.

[0141] like Figure 5AAs shown, the first main surface side external electrode 411A of the first external electrode 40A includes a first main surface side base electrode layer 511A arranged on the first main surface TS1 and a first main surface side plating layer 611A including a first Ni plating layer 61A and a first Sn plating layer 62A. The first main surface side recessed portion 510A is formed by the first Sn plating layer 62A of the outermost first main surface side plating layer 611A, the first Ni plating layer 61A below the first Sn plating layer 62A, and the first main surface side base electrode layer 511A below the first Ni plating layer 61A being stacked in the stacking direction T (in the stacking direction T). Figure 5A 、 Figure 5B (corresponding to the Z direction) is recessed toward the stacked body 10 side.

[0142] Therefore, the thickness of the first principal surface side foundation electrode layer 511A corresponding to the stacking direction T is smallest at the portion corresponding to the first principal surface side recess 510A. In the embodiment, the maximum thickness of the first principal surface side foundation electrode layer 511A is preferably 15 μm to 30 μm, for example.

[0143] The first principal surface side base electrode layer 511A of the first principal surface side external electrode 411A in the first external electrode 40A has a recess corresponding region 550 corresponding to the first principal surface side recess 510A and a recessed region 550 extending in the longitudinal direction L (in the longitudinal direction L). Figure 5A 、 Figure 5B An inner peripheral region 560 and an outer peripheral region 570 serving as peripheral regions adjacent to the recess corresponding region 550 in the middle (corresponding to the X direction) are provided.

[0144] The recessed portion corresponding region 550 is a region corresponding to the first principal surface side recessed portion 510A in the stacking direction T within the first principal surface side base electrode layer 511A.

[0145] The inner peripheral area 560 is an area in the first main surface side base electrode layer 511A that is closer to the inside than the recess corresponding area 550 in the longitudinal direction L, that is, on the central side of the longitudinal direction L of the stack 10 (the side away from the first end surface LS1 in the longitudinal direction L), and is an area with a range approximately equal to that of the recess corresponding area 550 in the longitudinal direction L starting from the recess corresponding area 550.

[0146] The outer peripheral area 570 is an area on the outside of the recess corresponding area 550 in the longitudinal direction L within the first main surface side base electrode layer 511A, that is, an area on the outside of the longitudinal direction L of the stack 10 (on the side close to the first end surface LS1 in the longitudinal direction L), and is an area with a range approximately equal to that of the recess corresponding area 550 in the longitudinal direction L starting from the recess corresponding area 550.

[0147] like Figure 5BAs shown, the surface of the first main surface side external electrode 411A has the above-mentioned first main surface side recess 510A, and has a first bulge 710 on the above-mentioned inner side of the first main surface side recess 510A, and has a second bulge 720 on the above-mentioned outer side of the first main surface side recess 510A.

[0148] Figure 5B Reference numeral 700 indicates an area in the longitudinal direction L of the first principal surface side recessed portion 510A (recess corresponding region 550) in the embodiment. The area 700 in the longitudinal direction L of the first principal surface side recessed portion 510A is based on the distance in the longitudinal direction L between a first midpoint 510m1 of a line connecting the deepest portion 510d of the first principal surface side recessed portion 510A and the apex 710p of the first raised portion 710, and a second midpoint 510m2 of a line connecting the deepest portion 510d of the first principal surface side recessed portion 510A and the apex 720p of the second raised portion 720. The deepest portion 510d of the first principal surface side recessed portion 510A is the portion of the first principal surface side recessed portion 510A that is closest to the first principal surface TS1 of the stacked body 10 in the stacking direction T. The vertex 710p of the first raised portion 710 is the point on the surface of the first raised portion 710 that is farthest from the first main surface TS1 of the stacked body 10 in the stacking direction T. The vertex 720p of the second raised portion 720 is the point on the surface of the second raised portion 720 that is farthest from the first main surface TS1 of the stacked body 10 in the stacking direction T.

[0149] The distance in the stacking direction T between the vertex 710p of the first raised portion 710 and the first main surface TS1 of the stacked body 10 is the height 710H of the first raised portion 710. The distance in the stacking direction T between the vertex 720p of the second raised portion 720 and the first main surface TS1 of the stacked body 10 is the height 720H ​​of the second raised portion 720. In the embodiment, the height 710H of the first raised portion 710 and the height 720H ​​of the second raised portion 720 may be the same or different. In different situations, the height 710H of the first raised portion 710 may be higher than the height 720H ​​of the second raised portion 720, or conversely, the height 710H of the first raised portion 710 may be lower than the height 720H ​​of the second raised portion 720.

[0150] like Figure 5B As shown, in the embodiment, the depth D of the first main surface side recess 510A is the shortest distance between a line connecting the apex 710 p of the first protrusion 710 and the apex 720 p of the second protrusion 720 and the deepest portion 510 d.

[0151] In the embodiment, the depth D of the first main surface side recess 510A is preferably 3 μm or more and 10 μm or less.

[0152] In the embodiment, the depth D of the first main surface side recess 510A is preferably greater than the thickness of the Ni plating layer 61A in the stacking direction T.

[0153] like Figure 5B As shown, in the embodiment, the distance 730L between the apex 710p of the first protrusion 710 and the apex 720p of the second protrusion 720 in the longitudinal direction L is preferably 50 μm to 400 μm. Furthermore, the distance 730L is preferably greater than the maximum thickness of the first principal surface side base electrode layer 511A.

[0154] like Figure 5B As shown, in the embodiment, a distance 740L in the longitudinal direction L between the inner end 560a of the first principal surface side base electrode layer 511A and the deepest portion 510d of the first principal surface side recess 510A is preferably 50 μm or more and 400 μm or less.

[0155] like Figure 5B As shown, in the embodiment, the distance 750L in the longitudinal direction L between the inner end 560 a of the first principal-surface-side base electrode layer 511A and the apex 710 p of the first protrusion 710 is preferably 50 μm or more and 200 μm or less.

[0156] The inner peripheral region 560 is a region in the first principal surface side foundation electrode layer 511A corresponding to the first protrusion 710 , and the outer peripheral region 570 is a region in the first principal surface side foundation electrode layer 511A corresponding to the second protrusion 720 .

[0157] like Figure 5A As shown, the first principal surface side base electrode layer 511A includes a metal portion 800 and a plurality of non-metal portions 810 within the metal portion 800. The metal portion 800 includes at least one metal component selected from Cu, Ni, Ag, Pd, an Ag-Pd alloy, Au, and the like, which is included in the aforementioned sintered layer forming the first principal surface side base electrode layer 511A. The plurality of non-metal portions 810 are dispersed within the metal portion 800.

[0158] The non-metallic portion 810 may be primarily, but not entirely, voids and may be composed of a glass component containing Ba or Si. The non-metallic portion 810 has the function of alleviating stress generated by forces applied to the external electrodes. The following description will refer to the non-metallic portion 810 containing a glass component as voids 810.

[0159] In the first principal surface side base electrode layer 511A of the embodiment, the metal density of the recessed portion corresponding region 550 can be lower than the metal density of the inner peripheral region 560 corresponding to the first protrusion 710, and lower than the metal density of the outer peripheral region 570 corresponding to the second protrusion 720. The metal density herein corresponds to the area ratio occupied by the metal portion 800 in the first principal surface side base electrode layer 511A in the LT cross section.

[0160] In addition, in the first main surface side base electrode layer 511A of the embodiment, the following conditions are preferably adopted, namely, the metal density of the recess corresponding area 550 is at least 10% lower than the metal density of the inner peripheral area 560 corresponding to the first protrusion 710, and is 10% lower than the metal density of the outer peripheral area 570 corresponding to the second protrusion 720.

[0161] On the basis of satisfying the above conditions, for example, the metal density of the recess corresponding region 550 is preferably 85% or less, and more preferably 60% or more and 85% or less.

[0162] In addition, on the basis of satisfying the above conditions, for example, the metal density of the inner peripheral area 560 corresponding to the first bulge 710 and the metal density of the outer peripheral area 570 corresponding to the second bulge 720 are preferably greater than 85%, and more preferably greater than 90% and less than 95%.

[0163] In the LT cross section of the first principal surface side base electrode layer 511A, the average area of ​​the plurality of voids 810 existing in the recess corresponding region 550 is preferably larger than the average area of ​​the voids 810 in the inner peripheral region 560 and the outer peripheral region 570 .

[0164] In the multilayer ceramic capacitor 1 of the embodiment, the first main-surface-side external electrode 411A of the first external electrode 40A has a first main-surface-side recess 510A. Furthermore, the first main-surface-side base electrode layer 511A of the first main-surface-side external electrode 411A, which is in direct contact with the laminate 10, has a recess-corresponding region 550 corresponding to the first main-surface-side recess 510A; an inner peripheral region 560, which is located inward of the recess-corresponding region 550 in the longitudinal direction L; and an outer peripheral region 570, which is located outward of the recess-corresponding region 550 in the longitudinal direction L. The metal density of the recess-corresponding region 550 is lower than the metal density of the inner peripheral region 560 and the metal density of the outer peripheral region 570.

[0165] The metal density of the recess-corresponding region 550, which constitutes the central portion of the first principal-surface-side base electrode layer 511A in the longitudinal direction L, is lower than the metal density of the inner peripheral regions 560 and the outer peripheral regions 570 located on either side of the recess-corresponding region 550 in the longitudinal direction L. As a result, the recess-corresponding region 550 includes a larger number of non-metallic portions 810. Consequently, the recess-corresponding region 550 mitigates stress generated by forces applied to the external electrodes. Furthermore, the metal density of the recess-corresponding region 550, which constitutes the central portion of the first principal-surface-side base electrode layer 511A in the longitudinal direction L, is lower than the metal density of the inner peripheral regions 560 and the outer peripheral regions 570 located on either side of the recess-corresponding region 550 in the longitudinal direction L. Consequently, the recess-corresponding region 550 is more likely to have lower adhesion to the laminate 10 than the inner peripheral regions 560 and the outer peripheral regions 570. For example, when the external electrodes of the multilayer ceramic capacitor 1 are mounted on a substrate (assuming that the first main surface side external electrode 411A is attached to the substrate by welding or other means), the bending stress generated in the first main surface side external electrode 411A is particularly concentrated on the Figure 5B The inner end 411e of the first principal-surface-side external electrode 411A or the inner end 560a of the first principal-surface-side base electrode layer 511A shown in FIG2 is transmitted as tensile stress to the laminate 10, potentially causing cracks, etc. in the laminate 10. However, if the adhesion strength of the recessed portion corresponding region 550 of the first principal-surface-side base electrode layer 511A to the laminate 10 is relatively low, as in the embodiment, the tensile stress due to the flexural stress that tends to concentrate on the inner end 411e and end 560a is also dispersed to the interface between the recessed portion corresponding region 550 and the laminate 10, where the adhesion strength is relatively low. As a result, the multilayer ceramic capacitor 1 of the embodiment can improve its flexural resistance. As a result, the occurrence of cracks, etc. in the laminate 10 can be suppressed.

[0166] Furthermore, in the multilayer ceramic capacitor 1 of the embodiment, the first main surface-side external electrode 411A of the first external electrode 40A includes a first main surface-side recess 510A. This forms a depression corresponding to the first main surface-side recess 510A in the first main surface-side base electrode layer 511A. This reduces the overall amount of the first main surface-side base electrode layer 511A compared to a case without the first main surface-side recess 510A. This reduction in overall amount is associated with a reduction in tensile stress due to flexural stress concentrated at the aforementioned inner end portion 411e and end 560a. This also improves flexural resistance, resulting in the suppression of cracks and the like in the laminate 10.

[0167] Next, a method for measuring various parameters, such as the depth D of the first principal surface side recess 510A, the average area of ​​the voids 810 within the first principal surface side base electrode layer 511A, and the metal density of the first principal surface side base electrode layer 511A, will be described in the LT cross-section of the multilayer ceramic capacitor 1. Hereinafter, the non-metallic portion 810 containing a glass component will also be referred to as the void 810.

[0168] First, the multilayer ceramic capacitor 1 is ground from the first side surface WS1 or the second side surface WS2 to a position approximately halfway along the width direction W. This exposes the LT cross-section of the multilayer ceramic capacitor 1 at the exact center along the width direction W. Next, the depth D of the first main surface side recess 510A in the LT cross-section exposed by grinding is measured using a digital microscope. This allows the depth D of the first main surface side recess 510A to be confirmed.

[0169] Next, the LT cross-section exposed by polishing was observed using a SEM. Specifically, a backscattered electron image was taken of the portion of the LT cross-section that included the first principal surface-side foundation electrode layer 511A. In the backscattered electron image, the difference in resistance values ​​is reflected as contrast, with the metal portion 800 appearing relatively white and the void 810 (non-metal portion 810) appearing darker than the metal portion 800. The imaging magnification was set to 2000x, and the backscattered electron image was taken of the concave portion-corresponding region 550, the inner peripheral region 560, and the outer peripheral region 570 within the first principal surface-side foundation electrode layer 511A as the analysis target areas.

[0170] The acquired reflected electron image was binarized using the image analysis software "WinROOF (manufactured by Mitani Shoji Co., Ltd.)" to identify the metal portion 800 and the plurality of voids 810 present within the metal portion 800. Using this binarized image, the average area and metal density of the plurality of voids 810 were calculated for the concave portion corresponding region 550, the inner peripheral region 560, and the outer peripheral region 570 within the first principal surface side base electrode layer 511A, which served as the analysis target range.

[0171] The area of ​​voids 810 is calculated based on the binarized image obtained by binarizing the reflected electron image. Based on the areas of each void 810 identified in recessed portion corresponding region 550, inner peripheral region 560, and outer peripheral region 570, the average area of ​​the plurality of voids 810 in each region is calculated.

[0172] Based on the areas of the recess corresponding region 550 , the inner peripheral region 560 , and the outer peripheral region 570 and the areas of the voids 810 in these regions (analysis target ranges), the area ratio of the voids 810 in these regions is calculated using the following formula (1).

[0173] Void area ratio (%) = (Void area / Analysis target area) × 100 … (1)

[0174] Based on the calculated area ratio of the gap 810 , the area ratio of the metal portion 800 in each of the recess corresponding region 550 , the inner peripheral region 560 , and the outer peripheral region 570 , that is, the metal density, is calculated using the following formula (2).

[0175] 100 (%) - area ratio of voids (%) = metal density (%) … (2)

[0176] The area ratio of the metal portion 800 in each of the recess corresponding region 550 , the inner peripheral region 560 , and the outer peripheral region 570 , that is, the metal density can also be calculated using the following formula (3).

[0177] Metal density (%) = (area of ​​metal part / area of ​​analysis target range) × 100 … (3)

[0178] Next, a method for manufacturing the multilayer ceramic capacitor 1 according to the embodiment will be described. The method for manufacturing the multilayer ceramic capacitor 1 according to the embodiment is not limited as long as the aforementioned requirements are met. However, a preferred manufacturing method includes the following steps. Details of each step are described below.

[0179] A dielectric sheet for dielectric layer 20 and a conductive paste for internal electrode layer 30 are prepared. Both the dielectric sheet for dielectric layer 20 and the conductive paste for internal electrode layer 30 contain a binder and a solvent. The binder and solvent can be known binders and solvents. For example, the conductive paste is a paste obtained by adding an organic binder and an organic solvent to metal powder.

[0180] For example, conductive paste for the internal electrode layer 30 is printed in a predetermined pattern on the dielectric sheet by screen printing, gravure printing, etc. Thus, a dielectric sheet having a pattern for the first internal electrode layer 31 and a dielectric sheet having a pattern for the second internal electrode layer 32 are prepared.

[0181] A predetermined number of dielectric sheets without the internal electrode layer 30 pattern printed thereon are stacked to form the portion on the first principal surface TS1 side that will become the first principal surface side outer layer portion 12. Dielectric sheets with the first internal electrode layer 31 pattern printed thereon and dielectric sheets with the second internal electrode layer 32 pattern printed thereon are then alternately stacked thereon. This forms the portion that will become the inner layer portion 11. A predetermined number of dielectric sheets without the internal electrode layer 30 pattern printed thereon are stacked thereon to form the portion on the second principal surface TS2 side that will become the second principal surface side outer layer portion 13. This completes the production of a laminated sheet.

[0182] The laminated sheets are pressed in the lamination direction by isostatic pressing or the like to produce a laminated block.

[0183] The stacked block is cut into pieces of a predetermined size to obtain a plurality of stacked small pieces. The stacked small pieces may then be polished by barrel polishing or the like to round the corners and ridges.

[0184] The stacked small pieces are fired to produce the stacked body 10. The firing temperature at this time depends on the materials of the dielectric layer 20 and the internal electrode layer 30, but is preferably 900°C or higher and 1400°C or lower, for example.

[0185] The first external electrode 40A and the second external electrode 40B are formed on both end surfaces of the laminate 10 as follows.

[0186] A conductive paste, which will become the first foundation electrode layer 50A, is applied to the first end face LS1 of the laminate 10. A conductive paste, which will become the second foundation electrode layer 50B, is applied to the second end face LS2 of the laminate 10. In the embodiment, the first foundation electrode layer 50A and the second foundation electrode layer 50B are sintered layers. The sintered layers are formed by applying a conductive paste containing a glass component and a metal to the laminate 10, for example, by dipping, and then sintering the paste. The sintering temperature is preferably, for example, 700°C or higher and 950°C or lower.

[0187] The first foundation electrode layer 50A and the second foundation electrode layer 50B are preferably sintered layers. This allows the first foundation electrode layer 50A and the second foundation electrode layer 50B to be formed using a relatively simple method compared to forming them using a thin film forming method such as sputtering or vapor deposition.

[0188] In an embodiment, impregnation is performed so that the conductive paste that will become the first main surface side base electrode layer 511A of the first base electrode layer 50A is configured to extend from the first end surface LS1 of the stack 10 to a portion of the first main surface TS1, and the conductive paste that will become the second main surface side base electrode layer 512A of the first base electrode layer 50A is configured to extend from the first end surface LS1 of the stack 10 to a portion of the second main surface TS2.

[0189] In addition, in an embodiment, impregnation is performed so that the conductive paste that will become the first principal surface side base electrode layer 511B of the second base electrode layer 50B is configured to extend from the second end surface LS2 of the stack 10 to a portion of the first principal surface TS1, and the conductive paste that will become the second principal surface side base electrode layer 512B of the second base electrode layer 50B is configured to extend from the second end surface LS2 of the stack 10 to a portion of the second principal surface TS2.

[0190] In addition, at this time, it is preferred to simultaneously perform impregnation so that the conductive paste that will become the first side surface side base electrode layer 521A of the first base electrode layer 50A is configured to extend from the first end surface LS1 of the stack 10 to a portion of the first side surface WS1, and the conductive paste that will become the second side surface side base electrode layer 522A of the first base electrode layer 50A is configured to extend from the first end surface LS1 of the stack 10 to a portion of the second side surface WS2.

[0191] In addition, at this time, it is preferred to simultaneously perform impregnation so that the conductive paste that will become the first side surface side base electrode layer 521B of the second base electrode layer 50B is configured to extend from the second end surface LS2 of the stack 10 to a portion of the first side surface WS1, and the conductive paste that will become the second side surface side base electrode layer 522B of the second base electrode layer 50B is configured to extend from the second end surface LS2 of the stack 10 to a portion of the second side surface WS2.

[0192] Alternatively, the pre-fired laminated pieces and the conductive paste applied to the laminated pieces may be fired simultaneously. In this case, the sintered layer is preferably formed by sintering a material to which a ceramic material has been added in place of the glass component. In this case, the added ceramic material is preferably the same type as that of the dielectric layer 20. In this case, the conductive paste is applied to the pre-fired laminated pieces, and the laminated pieces and the conductive paste applied to the laminated pieces are sintered simultaneously, thereby forming a laminate 10 having a sintered layer. Forming the sintered layer simultaneously with the sintering of the laminate 10 can simplify the manufacturing process.

[0193] Next, the surfaces of the first and second foundation electrode layers 50A, including the sintered layers, are plated. In the embodiment, a first plating layer 60A is formed on the surface of the first foundation electrode layer 50A. Furthermore, a second plating layer 60B is formed on the surface of the second foundation electrode layer 50B. In the embodiment, a first Ni plating layer 61A is formed on the surface of the first foundation electrode layer 50A, and a first Sn plating layer 62A is formed on the surface of the first Ni plating layer 61A. In the embodiment, a second Ni plating layer 61B is formed on the surface of the second foundation electrode layer 50B, and a second Sn plating layer 62B is formed on the surface of the second Ni plating layer 61B.

[0194] When performing the plating process, either electrolytic plating or electroless plating can be used. However, electroless plating requires pretreatment with a catalyst to increase the deposition rate of the coating, which has the disadvantage of complicating the process. Therefore, electrolytic plating is generally preferred. The Ni plating layer and the Sn plating layer are preferably formed sequentially by, for example, barrel plating.

[0195] Here, when obtaining the above-mentioned groove-shaped recessed portions in each main surface side external electrode and each side surface side external electrode of the external electrode 40 as in the embodiment, for example, the following methods can be mentioned.

[0196] Figure 6A as well as Figure 6B The process of forming the base electrode layer in this method is schematically shown. Figure 6A As shown, the first conductive paste P, which becomes the base electrode layer, is applied by dipping the end portion in the longitudinal direction L of the stack 10. Then, it is dried to volatilize the organic component. At this time, there is a difference in drying speed between the portion where the conductive paste P is thickly attached as a coating and the portion where it is thinly attached. Specifically, the portion where it is thinly attached dries faster. Through the capillary flow from the portion where the coating is thick to the portion where the coating is thin, which is caused by the difference in drying speed, the solid component moves to the side of the portion where the coating is thin. Specifically, by adjusting the composition and drying conditions of the conductive paste P, as shown in FIG. Figure 6B The solid content of the conductive paste P shown is directed toward the periphery of the end portion of the base electrode layer where the coating film is thin ( Figure 5A The conductive paste P moves toward the edge of the laminate 10 (around the end 560a in the middle), and gradually dries. This forms recesses G and raised portions 710 and 720, and the metal density in the areas corresponding to the recesses decreases. The recesses G become the aforementioned first main surface side recesses 510A, second main surface side recesses 520A, first side surface recesses 530A, second side surface recesses 540A, first main surface side recesses 510B, second main surface side recesses 520B, first side surface recesses 530B, and second side surface recesses 540B. By adjusting the composition of the conductive paste P and the drying conditions, the formation of the recesses G and the metal density in the areas corresponding to the recesses can be adjusted.

[0197] Through the above-described manufacturing steps, the multilayer ceramic capacitor 1 can be manufactured.

[0198] The structure of the multilayer ceramic capacitor 1 is not limited to Figures 1 to 4B For example, the multilayer ceramic capacitor 1 may also be as shown in FIG. Figure 7A 、 Figure 7B as well as Figure 7C The following are multilayer ceramic capacitors with dual, triple, and quadruple structures.

[0199] Figure 7A The multilayer ceramic capacitor 1 shown is a multilayer ceramic capacitor 1 of a two-layer structure, and as an internal electrode layer 30, in addition to the first internal electrode layer 33 and the second internal electrode layer 34, it also has a floating internal electrode layer 35 as a floating internal conductor layer that is not extended to either the first end surface LS1 or the second end surface LS2.

[0200] Figure 7B The illustrated multilayer ceramic capacitor 1 is a multilayer ceramic capacitor 1 having a triple structure including a first floating internal electrode layer 35A and a second floating internal electrode layer 35B as floating internal electrode layers 35 .

[0201] Figure 7C The illustrated multilayer ceramic capacitor 1 is a quadruple structure multilayer ceramic capacitor 1 including a first floating internal electrode layer 35A, a second floating internal electrode layer 35B, and a third floating internal electrode layer 35C as floating internal electrode layers 35 .

[0202] By providing the floating internal electrode layer 35 as the internal electrode layer 30, the multilayer ceramic capacitor 1 has a structure in which the opposing electrode portion is divided into multiple components. This results in a structure in which multiple capacitor components are formed between the opposing internal electrode layers 30, and these capacitor components are connected in series. As a result, the voltage applied to each capacitor component is reduced, and the multilayer ceramic capacitor 1 can achieve a higher withstand voltage. Furthermore, it goes without saying that the multilayer ceramic capacitor 1 of the embodiment can also have a multi-cell structure of four or more.

[0203] Even in Figure 7A 、 Figure 7B as well as Figure 7C In the multilayer ceramic capacitor 1 having the structure shown, similarly to the above-described embodiment, the first external electrode 40A has the first main surface side recess 510A and the second main surface side recess 520A, and the second external electrode 40B has the first main surface side recess 510B and the second main surface side recess 520B.

[0204] In addition, even in Figure 7A 、 Figure 7B as well as Figure 7C In the multilayer ceramic capacitor 1 having the structure shown, similarly to the above-described embodiment, the first external electrode 40A may have the first side surface recess 530A and the second side surface recess 540A, and the second external electrode 40B may have the first side surface recess 530B and the second side surface recess 540B.

[0205] In particular, even in Figures 7A to 7C In the multilayer ceramic capacitor 1 having a double structure, a triple structure, or a quadruple structure with a floating internal electrode layer 35 shown, for example, recesses (first main surface side recesses, second main surface side recesses) can be provided on the external electrodes on the main surface side, as in the embodiment, and the metal density of the area 550 corresponding to the recesses can be made lower than the metal density of the peripheral areas (inner peripheral area 560 and outer peripheral area 570), thereby improving the flexural resistance as described above, and as a result, suppressing the occurrence of cracks in the multilayer body 10.

[0206] According to the multilayer ceramic capacitor 1 according to the embodiment described above, the following effects are achieved.

[0207] (1) A multilayer ceramic capacitor 1 according to an embodiment includes a multilayer body 10 including a plurality of dielectric layers 20 serving as ceramic layers and a plurality of internal electrode layers 30 serving as internal conductive layers alternately stacked in a stacking direction T, and including a first main surface TS1 and a second main surface TS2 facing each other in the stacking direction T, a first end surface LS1 and a second end surface LS2 facing each other in a longitudinal direction L perpendicular to the stacking direction T, and a first side surface WS1 and a second side surface WS2 facing each other in a width direction W perpendicular to the stacking direction T and the longitudinal direction L.and a pair of external electrodes 40, which are arranged at both ends of the stack 10 in the longitudinal direction L, separated from each other. The internal electrode layer 30 includes a first internal electrode layer 31 as a first internal conductor layer extending to the first end surface LS1, and a second internal electrode layer 32 as a second internal conductor layer extending to the second end surface LS2. The external electrodes 40 include a first main surface side external electrode 411A and a second main surface side external electrode 412A, and a first main surface side external electrode 411B and a second main surface side external electrode 412B as main surface side external electrodes, which are arranged on the first main surface TS1 and the second main surface TS2, respectively. The first main surface side external electrode 411A and the second main surface side external electrode 412A and the first main surface side external electrode 411B and the second main surface side external electrode 412B respectively include the first main surface side base electrode layer 511A and the second main surface side base electrode layer 512A and the first main surface side base electrode layer 511B and the second main surface side base electrode layer 512B as the main surface side base electrode layer, and the main surface side base electrode layer formed on the upper layer of the first main surface side base electrode layer 511A and the second main surface side base electrode layer 512A and the first main surface side base electrode layer 511B and the second main surface side base electrode layer 512B. The first main surface side plating layer 611A and the second main surface side plating layer 612A and the first main surface side plating layer 611B and the second main surface side plating layer 612B of the plating layer, the first main surface side external electrode 411A and the second main surface side external electrode 412A and the first main surface side external electrode 411B and the second main surface side external electrode 412B respectively have the first main surface side recessed portion 510A and the second main surface side recessed portion 520A and the first main surface side recessed portion 510B and the second main surface side recessed portion 520B as recessed portions that are recessed toward the stacked body 10 side in a cross-section along the stacking direction T and the longitudinal direction L, and the first main surface side base electrode The layer 511A, the second principal surface side base electrode layer 512A, the first principal surface side base electrode layer 511B, and the second principal surface side base electrode layer 512B each have a recess corresponding region 550 corresponding to the first principal surface side recess 510A, the second principal surface side recess 520A, and the first principal surface side recess 510B, the second principal surface side recess 520B, and an inner peripheral region 560 and an outer peripheral region 570 as peripheral regions adjacent to the recess corresponding region 550 in the longitudinal direction L. The metal density of the recess corresponding region 550 is lower than the metal density of the inner peripheral region 560 and the outer peripheral region 570.

[0208] Thus, the multilayer ceramic capacitor 1 according to the embodiment can improve the flexural resistance when mounted on a substrate, and as a result, the occurrence of cracks in the multilayer body 10 can be suppressed.

[0209] (2) In the multilayer ceramic capacitor 1 of the above (1) according to the embodiment, the metal density of the recess corresponding region 550 is preferably 85% or less.

[0210] This can improve the flexural resistance when mounting on a substrate, and as a result, can suppress the occurrence of cracks in the laminate 10 .

[0211] (3) In the multilayer ceramic capacitor 1 of (1) above according to the embodiment, the metal density of the recess corresponding region 550 is preferably 60% or more and 85% or less.

[0212] This can improve the flexural resistance when mounting on a substrate, and as a result, can suppress the occurrence of cracks in the laminate 10 .

[0213] (4) In the multilayer ceramic capacitor 1 of (1) or (2) described above, the embodiment includes a mode in which the internal electrode layer 30 includes a floating internal electrode layer 35 as a floating internal conductor layer, which is not extended to either the first end surface LS1 or the second end surface LS2 and is opposed to at least one of the first internal electrode layer 31 and the second internal electrode layer 32 with the dielectric layer 20 interposed therebetween.

[0214] This makes it possible to increase the withstand voltage of the multilayer ceramic capacitor 1 .

[0215] The multilayer ceramic capacitor 1 of the embodiment may also include the following structure, namely, the first external electrode 40A and the second external electrode 40B each include a side external electrode, each of which has a recess similar to that of the main surface external electrode, and the metal density of the area corresponding to the recess in the base electrode layer of the side external electrode is lower than the metal density of the surrounding area corresponding to the recess.

[0216] That is, the multilayer ceramic capacitor 1 according to the embodiment includes:

[0217] A laminate 10 comprising a plurality of dielectric layers 20 serving as ceramic layers and a plurality of internal electrode layers 30 serving as internal conductor layers alternately stacked in a stacking direction T, and comprising a first main surface TS1 and a second main surface TS2 opposing each other in the stacking direction T, a first end surface LS1 and a second end surface LS2 opposing each other in a longitudinal direction L perpendicular to the stacking direction T, and a first side surface WS1 and a second side surface WS2 opposing each other in a width direction W perpendicular to the stacking direction T and the longitudinal direction L; and

[0218] A pair of external electrodes 40 are disposed at two ends of the stacked body 10 in the longitudinal direction L, separated from each other.

[0219] The inner conductor layer comprises:

[0220] A first internal electrode layer 31 as a first internal conductor layer is led out to the first end surface LS1; and

[0221] The second internal electrode layer 32, which is the second internal conductor layer, is led out to the second end surface LS2.

[0222] The external electrode 40 includes a side surface external electrode disposed on at least one of the first side surface WS1 and the second side surface WS2.

[0223] The side external electrode has:

[0224] a lateral substrate electrode layer; and

[0225] The side plated layer is formed above the side base electrode layer.

[0226] The side external electrode has a recessed portion that is recessed toward the stacked body 10 in a cross-sectional view along the width direction W and the length direction L.

[0227] The side substrate electrode layer has:

[0228] a concave portion corresponding area, corresponding to the concave portion; and

[0229] The peripheral area is adjacent to the area corresponding to the recess in the longitudinal direction L.

[0230] The metal density of the area corresponding to the recess is lower than the metal density of the peripheral area.

[0231] The present invention is not limited to the configuration of the above embodiment, and can be applied with appropriate modifications within the scope of the present invention. In addition, a combination of two or more configurations of the preferred configurations described in the above embodiment also constitutes the present invention.

[0232] For example, the multilayer ceramic capacitor 1 may be a two-terminal multilayer ceramic capacitor having two external electrodes, or may be a multi-terminal multilayer ceramic capacitor having a large number of external electrodes.

[0233] In the above embodiment, a multilayer ceramic capacitor using dielectric ceramics is exemplified as a multilayer ceramic electronic component. However, the multilayer ceramic electronic component disclosed herein is not limited to this application and can be applied to various multilayer ceramic electronic components, such as piezoelectric components using piezoelectric ceramics, thermistors using semiconductor ceramics, and inductors using magnetic ceramics. Examples of piezoelectric ceramics include PZT (lead zirconate titanate) ceramics, semiconductor ceramics include spinel ceramics, and magnetic ceramics include ferrites.

[0234] [Example]

[0235] The following is an explanation of the embodiments. As samples of Example 1 and Example 2 shown in Table 1, the following multilayer ceramic capacitors were produced in batch units according to the manufacturing method described in the above embodiment, that is, the first external electrode and the second external electrode respectively have a first main surface side recess and a second main surface side recess, and the metal density of the area corresponding to the recess is different from the metal density of the inner peripheral area and the outer peripheral area. The samples in each batch are manufactured under the same manufacturing conditions. According to each of the embodiments, n=20 samples for metal density measurement and n=30 samples for substrate bending resistance test were taken out from the same batch and prepared. In the metal density measurement, the average value of the measurement results was used for evaluation. In addition, the metal density was measured in accordance with the measurement method of the above embodiment.

[0236] During production, each multilayer ceramic capacitor was fabricated according to the following specifications.

[0237] Dimensions of a multilayer ceramic capacitor: L×W×T=1.6mm×0.8mm×0.8mm

[0238] Dielectric layer: BaTiO3

[0239] Capacitor: 10μF

[0240] Rated voltage: 25V

[0241] Base electrode layer: Electrode composed of a conductive metal (Cu) and a glass component (thickness of the base electrode layer disposed on the first and second end surfaces: 36 μm)

[0242] Plating layer: Made up of two layers: Ni plating layer (2μm) and Sn plating layer (4μm)

[0243] Internal electrode layer: Ni

[0244] On the other hand, as samples of Comparative Example 1, Comparative Example 2, and Comparative Example 3 shown in Table 1, multilayer ceramic capacitors were produced in which both the first external electrode and the second external electrode did not have the first main surface side recess and the second main surface side recess, and only the same number of samples as in the embodiment were prepared for each.

[0245] Furthermore, as comparative example 4 shown in Table 1, a multilayer ceramic capacitor was produced in which the first external electrode and the second external electrode respectively had a first main surface side recess and a second main surface side recess, but the metal density of the area corresponding to the recess was not lower than the metal density of the surrounding area, and only the same number of samples as in the embodiment were prepared.

[0246] The multilayer ceramic capacitors of Example 1, Example 2, and Comparative Examples 1 to 4 were subjected to a substrate bending resistance test, which reflects the flexural resistance, and the results were evaluated.

[0247] The outline of the substrate bending resistance test is as follows. A multilayer ceramic capacitor is mounted on a glass cloth-based epoxy resin printed wiring board. A pressing rod is attached to the back of the mounting surface to perform three-point bending and confirm whether cracks have occurred in the multilayer ceramic capacitor. At this time, a load is applied at a speed of 1.0 mm / s at the center of the test material and maintained for 5±1 seconds after reaching the specified deflection amount. In accordance with JIS C 60069-2-21, it is maintained for 20±1 seconds. Defective detection is based on the premise that no cracks occur. At this time, if the electrostatic capacitance change rate does not meet the individual regulations, it is also considered defective. Here, if cracks occur before reaching the predetermined bending amount, it is considered defective at that time. Then, an appearance inspection and cross-section grinding are performed to confirm that no cracks have occurred. In addition, as an evaluation, all small pieces are evaluated as "A", and those with more than one and less than three defective small pieces are evaluated as "B", and those with more than four defective small pieces are evaluated as "C".

[0248] [Table 1]

[0249]

[0250] According to Table 1, in Comparative Examples 1 and 2, the metal density in the approximately central region in the longitudinal direction of the main-surface-side external electrode is lower than that in the peripheral region. However, since the main-surface-side external electrode does not have a recess, the flexural resistance is not good. In Comparative Example 3, the metal density in the approximately central region in the longitudinal direction of the main-surface-side external electrode is not lower than that in the peripheral region. Furthermore, since the main-surface-side external electrode does not have a recess, the flexural resistance is not good. In Comparative Example 4, the main-surface-side external electrode has a recess, but the metal density in the recessed region (the approximately central region in the longitudinal direction of the main-surface-side external electrode) is higher than that in the peripheral region. Therefore, the flexural resistance is not good.

[0251] In contrast, Examples 1 and 2 have recessed portions in the main surface-side external electrodes, and the metal density in the recessed region (approximately the center region in the longitudinal direction of the main surface-side external electrode) is lower than that in the surrounding region, resulting in excellent flexural resistance. Therefore, it is clear that the following conditions are effective in achieving improved flexural resistance: not only the presence of recessed portions, but also the lower metal density in the region corresponding to the recessed portions compared to the surrounding region.

Claims

1. A multilayer ceramic electronic component comprising: a laminate comprising a plurality of ceramic layers and a plurality of internal conductor layers alternately stacked in a stacking direction, and comprising a first main surface and a second main surface opposing each other in the stacking direction, a first end surface and a second end surface opposing each other in a longitudinal direction perpendicular to the stacking direction, and a first side surface and a second side surface opposing each other in a width direction perpendicular to the stacking direction and the longitudinal direction; and A pair of external electrodes are disposed at two ends of the stack in the longitudinal direction thereof, separated from each other. The inner conductor layer comprises: a first internal conductor layer extending to the first end surface; and The second internal conductor layer is led out to the second end surface, The external electrodes include: a main surface side external electrode arranged on at least one of the first main surface and the second main surface; The main surface side external electrode has: a main surface side base electrode layer; and The main surface side plating layer is formed above the main surface side base electrode layer. The main surface side external electrode has a recessed portion that is recessed toward the stacked body in a cross-sectional view along the stacking direction and the longitudinal direction. The main surface side base electrode layer has: a concave portion corresponding area, corresponding to the concave portion; and The peripheral area is adjacent to the area corresponding to the recess in the longitudinal direction. The metal density of the area corresponding to the recess is lower than the metal density of the peripheral area.

2. The multilayer ceramic electronic component according to claim 1, wherein The metal density of the area corresponding to the recess is less than 85%.

3. The multilayer ceramic electronic component according to claim 1, wherein The metal density of the area corresponding to the recess is greater than or equal to 60% and less than or equal to 85%.

4. The multilayer ceramic electronic component according to claim 1 or 2, wherein The internal conductive layer includes a floating internal conductive layer that is not drawn out to either the first end surface or the second end surface and faces at least one of the first internal conductive layer and the second internal conductive layer with the ceramic layer interposed therebetween.

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