Multilayer ceramic electronic components

Abstract

The present invention provides a laminated ceramic electronic component that can effectively suppress cracks formed in a laminated ceramic electronic component. A laminated ceramic capacitor (10) as an example of a laminated ceramic electronic component according to the present invention comprises: a laminate (12) in which a plurality of ceramic layers (14) and a plurality of internal electrode layers (16) are laminated; and a pair of external electrodes (30) electrically connected to the internal electrode layers (16) and formed on both end surfaces of the laminate (12). The pair of external electrodes (30) comprises: a base electrode layer (32) having a metal component and a ceramic component; and a plating layer (34) disposed on the base electrode layer (32). Furthermore, a fatty acid is present at least on the surface of the base electrode layer (32).

Description

Technical Field

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

[0002] In recent years, ceramic electronic components, such as multilayer ceramic capacitors, are being used in harsher environments than before. For example, electronic components used in mobile devices such as mobile phones and portable music players are required to withstand the impact of being dropped. Specifically, it is necessary that even if the electronic components are subjected to the impact of being dropped, the electronic components will not fall off the mounting substrate, or cracks will not be generated in the electronic components.

[0003] In addition, electronic components used in vehicle-mounted devices such as ECUs (Electronic Control Units) are required to withstand the impact of thermal cycles. Specifically, it is necessary to prevent cracks from occurring in the electronic components even if the mounting substrate is subjected to bending stress caused by thermal expansion and contraction of the mounting substrate during thermal cycles.

[0004] In view of this, a proposal has been made to use a thermosetting resin paste for the external electrodes of ceramic electronic components. For example, in Patent Document 1, a countermeasure is taken in which an epoxy-based thermosetting resin layer is formed between the conventional electrode layer and the Ni plating layer, thereby preventing cracks from being generated in the capacitor body even in a harsh environment (improvement of bending resistance).

[0005] In such a structure, when stress is generated by the impact during falling and bending stress is generated due to thermal expansion of the mounting substrate due to a heat cycle, the stress transmitted to the mounting substrate (deformation of the mounting substrate) is released by peeling between the electrode layer and the epoxy-based thermosetting resin layer starting from the front end of the epoxy-based thermosetting resin, thereby suppressing the occurrence of cracks in the ceramic electronic component body (laminate).

[0006] Prior Art Literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 11-162771

[0009] However, even in the structure of Patent Document 1, it is considered that, depending on the design of the multilayer ceramic capacitor, stress absorption or stress relaxation by the peeling function of the thermosetting resin may be insufficient, and cracks may occur in the ceramic electronic component body. Summary of the invention

[0010] Problem that the invention aims to solve

[0011] Therefore, a main object of the present invention is to provide a multilayer ceramic electronic component capable of effectively suppressing cracks from forming in the multilayer ceramic electronic component.

[0012] Technical solutions to solve problems

[0013] The laminated ceramic electronic component of the present invention is a laminated ceramic electronic component comprising: a laminated body including a plurality of laminated ceramic layers, and having a first main surface and a second main surface opposite to each other in a height direction, a first side surface and a second side surface opposite to each other in a width direction perpendicular to the height direction, and a first end surface and a second end surface opposite to each other in a length direction perpendicular to the height direction and the width direction; a first internal electrode layer arranged on the plurality of ceramic layers and located inside the laminated body; a second internal electrode layer arranged on the plurality of ceramic layers and located inside the laminated body; a first external electrode arranged on the first end surface, a part of the first main surface, a part of the second main surface, a part of the first side surface, and a part of the second side surface; and a second external electrode arranged on the second end surface, a part of the first main surface, a part of the second main surface, a part of the first side surface, and a part of the second side surface, wherein the first external electrode and the second external electrode comprise: a base electrode layer including a metal component; and a plating layer arranged on the base electrode layer, wherein a fatty acid is present at least on a surface of the base electrode layer.

[0014] In the laminated ceramic electronic component according to the present invention, a fatty acid is present at least on the surface of the base electrode layer, so that the carboxyl group of the fatty acid is ionized and adsorbed to the base electrode layer by ionic bonding force, and the deposition of the plating layer provided on the base electrode layer can be hindered at the adsorption portion, and the bonding area between the base electrode layer and the plating layer can be reduced. Therefore, the adhesion between the base electrode layer and the plating layer is reduced, thereby achieving the effect of promoting the peeling of the base electrode layer and the plating layer formed thereon.

[0015] Therefore, when the multilayer ceramic electronic component according to the present invention is subjected to impact during drop or thermal cycle, the base electrode layer and the plating layer can be stably separated and stress can be released. As a result, cracks can be suppressed from occurring in the multilayer ceramic electronic component.

[0016] Furthermore, in a laminated ceramic electronic component, when a conductive resin layer is not provided on an external electrode, not only can cost be reduced, but also the degree of freedom in designing the laminated body increases according to the thickness of the conductive resin layer, thereby achieving higher capacitance.

[0017] Effects of the Invention

[0018] According to the present invention, it is possible to provide a multilayer ceramic electronic component capable of effectively suppressing cracks from forming in the multilayer ceramic electronic component.

[0019] The above-mentioned object, other objects, features and advantages of the present invention will become more apparent from the following description of the embodiment of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 FIG. 1 is a perspective view showing the appearance of an example of a multilayer ceramic capacitor as a multilayer ceramic electronic component according to an embodiment of the present invention.

[0021] Figure 2 yes Figure 1 Cross-sectional view at line II-II.

[0022] Figure 3 yes Figure 1 Cross-sectional view at line III-III.

[0023] Figure 4 yes Figure 2 Cross-sectional view at line IV-IV.

[0024] Figure 5 yes Figure 2 Cross-sectional view at line V-V.

[0025] FIG. 6(A) is a diagram showing a structure in which the opposing electrode portion of the internal electrode layer of the multilayer ceramic capacitor according to the embodiment of the present invention is divided into two. FIG. Figure 1 FIG. 6(B) is a cross-sectional view taken along line II-II of FIG. 6 , and FIG. 6(B) is a cross-sectional view showing a structure in which the opposing electrode portion of the internal electrode layer of the multilayer ceramic capacitor according to the present invention is divided into three. Figure 1 FIG. 6(C) is a cross-sectional view taken along line II-II of FIG. 6 , showing a structure in which the opposing electrode portion of the internal electrode layer of the multilayer ceramic capacitor according to the present invention is divided into four. Figure 1 Cross-sectional view at line II-II.

[0026] Figure 7 This is a perspective view of main parts showing a method for detecting fatty acids contained in a multilayer ceramic capacitor as a multilayer ceramic electronic component according to an embodiment of the present invention.

[0027] Figure 8 yes Figure 7 Cross-sectional view at line VIII-VIII.

[0028] Fig. 9 A multilayer ceramic capacitor is an example of a multilayer ceramic electronic component according to a modified example of an embodiment of the present invention. Figure 2 The corresponding cross-sectional view.

[0029] 10(A) is a schematic cross-sectional view showing a method for measuring the thickness of a fatty acid on a base electrode layer, and FIG. 10(B) is a schematic cross-sectional view showing a method for measuring the thickness of a fatty acid on a surface of a laminate.

[0030] Fig.11 A multilayer ceramic capacitor is an example of a multilayer ceramic electronic component according to another modified example of the embodiment of the present invention. Figure 2 The corresponding cross-sectional view.

[0031] Description of Reference Numerals

[0032] 10: Multilayer ceramic capacitor;

[0033] 12: laminate;

[0034] 12a: 1st main side;

[0035] 12b: 2nd main side;

[0036] 12c: 1st side;

[0037] 12d: lateral side 2;

[0038] 12e: 1st end surface;

[0039] 12f: 2nd end surface;

[0040] 14: Ceramic layer;

[0041] 16: internal electrode layer;

[0042] 16a: first internal electrode layer;

[0043] 16b: second internal electrode layer;

[0044] 18: inner layer;

[0045] 20a: first main surface side outer layer portion;

[0046] 20b: outer layer portion on the second main surface side;

[0047] 22a: first side outer layer portion;

[0048] 22b: 2nd side outer layer portion;

[0049] 24a: first end surface side outer layer portion;

[0050] 24b: second end surface side outer layer portion;

[0051] 26a: first opposing electrode portion;

[0052] 26b: second opposing electrode portion;

[0053] 28a: first lead electrode portion;

[0054] 28b: second lead electrode portion;

[0055] 30: external electrode;

[0056] 30a: 1st external electrode;

[0057] 30b: second external electrode;

[0058] 32: base electrode layer;

[0059] 32a: first base electrode layer;

[0060] 32b: second base electrode layer;

[0061] 34: plating layer;

[0062] 34a: first plating layer;

[0063] 34b: second plating layer;

[0064] 36: conductive resin layer;

[0065] 36a: first conductive resin layer;

[0066] 36b: second conductive resin layer;

[0067] 38: front end;

[0068] 40: fatty acids;

[0069] 50: Au coating layer;

[0070] 100: Install the substrate;

[0071] 102: connection plate electrode;

[0072] 110: solder;

[0073] x: height direction;

[0074] y: width direction;

[0075] z: length direction. DETAILED DESCRIPTION

[0076] 1. Multilayer ceramic capacitors

[0077] A multilayer ceramic capacitor will be described as an example of a multilayer ceramic electronic component according to an embodiment of the present invention.

[0078] Figure 1 FIG. 1 is a perspective view showing the appearance of an example of a multilayer ceramic capacitor as a multilayer ceramic electronic component according to an embodiment of the present invention. Figure 2 yes Figure 1 Cross-sectional view at line II-II. Figure 3 yes Figure 1 Cross-sectional view at line III-III. Figure 4 yes Figure 2 Cross-sectional view at line IV-IV. Figure 5 yes Figure 2 Cross-sectional view at line V-V.

[0079] like Figures 1 to 3 As shown, the multilayer ceramic capacitor 10 includes a rectangular parallelepiped-shaped multilayer body 12 and external electrodes 30 disposed at both ends of the multilayer body 12 .

[0080] The laminate 12 has a plurality of stacked ceramic layers 14 and a plurality of internal electrode layers 16 stacked on the ceramic layers 14. Furthermore, the laminate 12 has a first main surface 12a and a second main surface 12b opposite to each other in the height direction x, a first side surface 12c and a second side surface 12d opposite to each other in the width direction y orthogonal to the height direction x, and a first end surface 12e and a second end surface 12f opposite to each other in the length direction z orthogonal to the height direction x and the width direction y. In the laminate 12, the corners and the ridges are rounded. In addition, the so-called corner refers to the part where three adjacent faces of the laminate intersect, and the so-called ridge refers to the part where two adjacent faces of the laminate intersect. In addition, the first main surface 12a and the second main surface 12b, the first side surface 12c and the second side surface 12d, and the first end surface 12e and the second end surface 12f may be partially or entirely formed with projections and depressions. The ceramic layers 14 and the internal electrode layers 16 are stacked in the height direction x.

[0081] The laminate 12 has an inner layer portion 18 composed of a single or multiple ceramic layers 14 and multiple internal electrode layers 16 arranged thereon. The internal electrode layer 16 has a first internal electrode layer 16a extending to a first end face 12e and a second internal electrode layer 16b extending to a second end face 12f. In the inner layer portion 18, multiple first internal electrode layers 16a and second internal electrode layers 16b are opposed to each other with the ceramic layer 14 interposed therebetween.

[0082] The stacked body 12 has a first main surface side outer layer portion 20a, which is located on the first main surface 12a side and is formed by a plurality of ceramic layers 14 located between the first main surface 12a and the outermost surface of the inner layer portion 18 on the first main surface 12a side and a straight line on the outermost surface.

[0083] Similarly, the stack 12 has a second main surface side outer layer portion 20b, which is located on the second main surface 12b side and is formed by a plurality of ceramic layers 14 located between the second main surface 12b and the outermost surface of the inner layer portion 18 on the second main surface 12b side and a straight line on the outermost surface.

[0084] The laminate 12 has a first side surface side outer layer portion 22a located on the first side surface 12c side and formed of a plurality of ceramic layers 14 located between the first side surface 12c and the outermost surface of the inner layer portion 18 on the first side surface 12c side.

[0085] Similarly, the laminate 12 has a second side outer layer portion 22b located on the second side 12d side and formed of a plurality of ceramic layers 14 located between the second side 12d and the outermost surface of the inner layer portion 18 on the second side 12d side.

[0086] The laminated body 12 has a first end surface side outer layer portion 24a located on the first end surface 12e side and formed of a plurality of ceramic layers 14 located between the first end surface 12e and the outermost surface of the inner layer portion 18 on the first end surface 12e side.

[0087] Similarly, the laminate 12 has a second end surface side outer layer portion 24b located on the second end surface 12f side and formed of a plurality of ceramic layers 14 located between the second end surface 12f and the outermost surface of the inner layer portion 18 on the second end surface 12f side.

[0088] The first principal surface side outer layer portion 20 a is located on the first principal surface 12 a side of the laminate 12 and is an assembly of a plurality of ceramic layers 14 located between the first principal surface 12 a and the internal electrode layer 16 closest to the first principal surface 12 a .

[0089] The second principal surface side outer layer portion 20 b is located on the second principal surface 12 b side of the laminate 12 and is an assembly of a plurality of ceramic layers 14 located between the second principal surface 12 b and the internal electrode layer 16 closest to the second principal surface 12 b .

[0090] The dimensions of the laminate 12 are not particularly limited, but preferably the dimension in the longitudinal direction z is 0.186 mm to 9.59 mm, the dimension in the width direction y is 0.086 mm to 9.59 mm, and the dimension in the height direction x is 0.086 mm to 9.59 mm.

[0091] The ceramic layer 14 can be formed of a dielectric material as a ceramic material, for example. As such a dielectric material, for example, a dielectric ceramic containing BaTiO3, CaTiO3, SrTiO3, or CaZrO3 can be used. In the case of containing the above-mentioned dielectric material as a main component, a material to which a secondary component such as a Mn compound, an Fe compound, a Cr compound, a Co compound, or a Ni compound whose content is less than that of the main component can be added according to the desired characteristics of the laminate 12.

[0092] When a piezoelectric ceramic material is used for the ceramic layer 14, the laminated ceramic electronic component functions as a piezoelectric component. Specific examples of the piezoelectric ceramic material include, for example, PZT (lead zirconate titanate)-based ceramic materials.

[0093] Furthermore, the laminated ceramic electronic component functions as a thermistor when a semiconductor ceramic material is used for the ceramic layer 14. Specific examples of the semiconductor ceramic material include spinel ceramic materials and the like.

[0094] In addition, when a magnetic ceramic material is used for the ceramic layer 14, the laminated ceramic electronic component functions as an inductor. In addition, when it functions as an inductor, the internal electrode layer 16 becomes a coil-shaped conductor. Specific examples of magnetic ceramic materials include ferrite ceramic materials.

[0095] The thickness of the ceramic layer 14 after firing is preferably 0.5 μm or more and 15 μm or less. The number of stacked ceramic layers 14 is preferably 10 or more and 700 or less. In addition, the number of ceramic layers 14 is the total number of ceramic layers 14 of the inner layer portion 18 and the number of ceramic layers 14 of the first main surface side outer layer portion 20a and the second main surface side outer layer portion 20b.

[0096] The laminate 12 includes, for example, substantially rectangular first internal electrode layers 16a and second internal electrode layers 16b as the plurality of internal electrode layers 16. The plurality of first internal electrode layers 16a and second internal electrode layers 16b are buried and alternately arranged at equal intervals with the ceramic layers 14 interposed therebetween along the height direction x of the laminate 12.

[0097] like Figure 4As shown, the first internal electrode layer 16a is arranged on the plurality of ceramic layers 14 and is located inside the stacked body 12. The first internal electrode layer 16a includes: a first opposing electrode portion 26a opposed to the second internal electrode layer 16b; and a first lead electrode portion 28a located on one end side of the first internal electrode layer 16a and extending from the first opposing electrode portion 26a to the first end surface 12e of the stacked body 12. The first lead electrode portion 28a has an end portion led out to the surface of the first end surface 12e and exposed from the stacked body 12.

[0098] The shape of the first counter electrode portion 26a of the first internal electrode layer 16a is not particularly limited, but is preferably rectangular in a plan view. However, the corners may be rounded in a plan view, or may be formed to be inclined (conical) in a plan view. In addition, the shape may be tapered in a plan view that is inclined in one direction.

[0099] The shape of the first lead electrode portion 28a of the first internal electrode layer 16a is not particularly limited, but is preferably rectangular in a plan view. However, the corners may be rounded in a plan view, or may be formed to be inclined (tapered) in a plan view. In addition, the shape may be tapered in a plan view with an inclination toward one direction.

[0100] The width of the first counter electrode portion 26a of the first internal electrode layer 16a and the width of the first lead electrode portion 28a of the first internal electrode layer 16a may be formed to be the same width, or one of the widths may be formed to be narrow.

[0101] like Figure 5 As shown, the second internal electrode layer 16b is arranged on the plurality of ceramic layers 14 and is located inside the stacked body 12. The second internal electrode layer 16b includes: a second opposing electrode portion 26b opposed to the first internal electrode layer 16a; and a second lead-out electrode portion 28b located on one end side of the second internal electrode layer 16b and extending from the second opposing electrode portion 26b to the second end face 12f of the stacked body 12. The end of the second lead-out electrode portion 28b is led out to the surface of the second end face 12f and exposed from the stacked body 12.

[0102] The shape of the second counter electrode portion 26b of the second internal electrode layer 16b is not particularly limited, but is preferably rectangular in a plan view. However, the corners may be rounded in a plan view, or may be formed to be inclined (conical) in a plan view. In addition, the shape may be a cone in a plan view that is inclined in one direction.

[0103] The shape of the second lead electrode portion 28b of the second internal electrode layer 16b is not particularly limited, but is preferably rectangular in a plan view. However, the shape may be rounded at the corners in a plan view, or may be formed to be inclined (conical) in a plan view. In addition, the shape may be a cone in a plan view that is inclined in one direction.

[0104] The width of the second counter electrode portion 26b of the second internal electrode layer 16b and the width of the second lead electrode portion 28b of the second internal electrode layer 16b may be formed to be the same width, or one of the widths may be formed to be narrower.

[0105] The first internal electrode layer 16 a and the second internal electrode layer 16 b can be formed of an appropriate conductive material such as a metal such as Ni, Cu, Ag, Pd, Au, or an alloy containing at least one of these metals such as an Ag—Pd alloy.

[0106] The thickness of each of the internal electrode layers 16 , that is, the first internal electrode layer 16 a and the second internal electrode layer 16 b is preferably 0.2 μm or more and 2.0 μm or less.

[0107] Furthermore, the total number of the first internal electrode layers 16 a and the second internal electrode layers 16 b is preferably 10 or more and 700 or less.

[0108] like Figures 1 to 3 As shown in FIG. 1 , the external electrodes 30 are arranged on the first end surface 12 e side and the second end surface 12 f side of the stacked body 12 .

[0109] The external electrode 30 includes a first external electrode 30 a and a second external electrode 30 b .

[0110] The first external electrode 30a is connected to the first internal electrode layer 16a and is disposed at least on the surface of the first end surface 12e. In addition, the first external electrode 30a is also extended from the first end surface 12e of the stacked body 12 and is disposed on a portion of the first main surface 12a and a portion of the second main surface 12b, and a portion of the first side surface 12c and a portion of the second side surface 12d. In this case, the first external electrode 30a is electrically connected to the first lead electrode portion 28a of the first internal electrode layer 16a.

[0111] The second external electrode 30b is connected to the second internal electrode layer 16b and is disposed at least on the surface of the second end surface 12f. In addition, the second external electrode 30b is also extended from the second end surface 12f and disposed on a portion of the first main surface 12a and a portion of the second main surface 12b, and a portion of the first side surface 12c and a portion of the second side surface 12d. In this case, the second external electrode 30b is electrically connected to the second lead electrode portion 28b of the second internal electrode layer 16b.

[0112] The external electrode 30 includes a base electrode layer 32 including a metal component and a plating layer 34 disposed on the base electrode layer 32 .

[0113] The first external electrode 30 a includes a first base electrode layer 32 a including a metal component and a first plating layer 34 a disposed on the first base electrode layer 32 a .

[0114] The second external electrode 30b includes a second foundation electrode layer 32b including a metal component and a second plating layer 34b disposed on the second foundation electrode layer 32b.

[0115] A conductive resin layer 36 having a metal component and a thermosetting resin component may be disposed between the base electrode layer 32 and the plating layer 34. Thus, even when a large impact is applied to the multilayer ceramic capacitor 10 when it is dropped or when a thermal cycle is applied, not only the electrode peeling effect by the fatty acid described later can be obtained, but also the stress absorption function of the resin component contained in the conductive resin layer 36 and the effect of sacrificial destruction in the resin component contained in the conductive resin layer can be obtained, and the effect of the present invention can be made more significant.

[0116] In the laminate 12, the first opposing electrode portion 26a of the first internal electrode layer 16a and the second opposing electrode portion 26b of the second internal electrode layer 16b are opposed to each other via the ceramic layer 14, thereby forming an electrostatic capacitor. Therefore, an electrostatic capacitor can be obtained between the first external electrode 30a connected to the first internal electrode layer 16a and the second external electrode 30b connected to the second internal electrode layer 16b, and the characteristics of a capacitor are exhibited.

[0117] in addition, Figure 1 The laminated body 12 shown may also be configured as follows, that is, as shown in FIG. 6 (A) to FIG. 6 (C), in addition to the first internal electrode layer 16a and the second internal electrode layer 16b, a floating internal electrode layer 16c that is not led to either the first end face 12e or the second end face 12f is provided, and the opposing electrode portion 26c is divided into a plurality of portions by the floating internal electrode layer 16c. For example, it is a two-piece structure as shown in FIG. 6 (A), a three-piece structure as shown in FIG. 6 (B), a four-piece structure as shown in FIG. 6 (C), and it is self-evident that it may be a structure of four or more. In this way, by configuring the structure in which the opposing electrode portion 26c is divided into a plurality of portions, a structure is formed in which a plurality of capacitor components are formed between the opposing internal electrode layers 16a, 16b, and 16c, and these capacitor components are connected in series. Therefore, the voltage applied to each capacitor component becomes lower, and the laminated ceramic capacitor 10 can be made to have a higher withstand voltage.

[0118] The foundation electrode layer 32 includes a first foundation electrode layer 32 a and a second foundation electrode layer 32 b .

[0119] The first foundation electrode layer 32a is connected to the first internal electrode layer 16a and is arranged on the surface of the first end surface 12e. In addition, the first foundation electrode layer 32a is also extended from the first end surface 12e and arranged on a part of the first main surface 12a and a part of the second main surface 12b, and a part of the first side surface 12c and a part of the second side surface 12d. In this case, the first foundation electrode layer 32a is electrically connected to the first extraction electrode portion 28a of the first internal electrode layer 16a.

[0120] The second foundation electrode layer 32b is connected to the second internal electrode layer 16b and is arranged on the surface of the second end surface 12f. In addition, the second foundation electrode layer 32b is also extended from the second end surface 12f and arranged on a part of the first main surface 12a and a part of the second main surface 12b, and a part of the first side surface 12c and a part of the second side surface 12d. In this case, the second foundation electrode layer 32b is electrically connected to the second extraction electrode portion 28b of the second internal electrode layer 16b.

[0121] The base electrode layer 32 contains a metal component. In addition, the base electrode layer 32 preferably contains a glass component or a ceramic component. This can improve the adhesion between the laminate 12 and the base electrode layer 32. In addition, the base electrode layer 32 may contain both a glass component and a ceramic component.

[0122] The metal component included in the base electrode layer 32 includes, for example, at least one selected from Cu, Ni, Ag, Pd, Ag-Pd alloy, Au, etc. The glass component included in the base electrode layer 32 includes at least one selected from B, Si, Ba, Mg, Al, Li, etc. In addition, the ceramic component may use the same type of ceramic material as the ceramic layer 14, or a ceramic material different from the ceramic layer 14. The ceramic component includes, for example, at least one selected from BaTiO3, CaTiO3, (Ba, Ca)TiO3, SrTiO3, CaZrO3, etc.

[0123] The base electrode layer 32 may be composed of a plurality of layers.

[0124] In the case where the base electrode layer 32 includes a metal component and a glass component, the base electrode layer 32 is a base electrode layer formed by applying a conductive paste including a glass component and a metal component to the laminate 12 and sintering the conductive paste. The base electrode layer 32 may be sintered simultaneously with the internal electrode layer 16 and the ceramic layer 14, or may be sintered after the internal electrode layer 16 and the ceramic layer 14 are sintered. In addition, regarding the base electrode layer 32, when the internal electrode layer 16 and the ceramic layer 14 are sintered simultaneously, it is preferred to add a ceramic material instead of a glass component to form the base electrode layer 32.

[0125] The thickness of the first foundation electrode layer 32a located at the center of the first end face 12e in the height direction x in the longitudinal direction z connecting the first end face 12e and the second end face 12f is preferably about 2 μm or more and 220 μm or less, for example.

[0126] The thickness in the length direction z connecting the first end face 12e and the second end face 12f at the center portion of the second foundation electrode layer 32b located at the second end face 12f in the height direction x is preferably about 2 μm or more and 220 μm or less, for example.

[0127] The thickness of the first base electrode layer 32a located on a portion of the first principal surface 12a and the second principal surface 12b in the height direction x connecting the first principal surface 12a and the second principal surface 12b at the center in the length direction z connecting the first end surface 12e and the second end surface 12f is preferably about 4 μm or more and 15 μm or less.

[0128] The thickness of the second base electrode layer 32b located on a portion of the first principal surface 12a and the second principal surface 12b in the height direction x connecting the first principal surface 12a and the second principal surface 12b at the center in the length direction z connecting the first end surface 12e and the second end surface 12f is preferably about 4 μm or more and 15 μm or less.

[0129] The thickness of the first base electrode layer 32a located on a portion of the first side surface 12c and the second side surface 12d in the width direction y connecting the first side surface 12c and the second side surface 12d at the center in the length direction z connecting the first end surface 12e and the second end surface 12f is preferably about 4 μm or more and 15 μm or less.

[0130] The thickness of the second base electrode layer 32b located on a portion of the first side surface 12c and the second side surface 12d in the width direction y connecting the first side surface 12c and the second side surface 12d at the center in the length direction z connecting the first end surface 12e and the second end surface 12f is preferably about 4 μm or more and 15 μm or less.

[0131] The fatty acid 40 is present at least on the surface of the base electrode layer 32. More specifically, the fatty acid 40 is present at least on the surface of the first base electrode layer 32a and the surface of the second base electrode layer 32b. As a result, the carboxyl group of the fatty acid is ionized and adsorbed to the base electrode layer 32 by ionic bonding force, and the deposition of the plating of the plating layer 34 provided on the base electrode layer 32 is inhibited in the adsorbed portion, and the bonding area between the base electrode layer 32 and the plating layer 34 can be reduced. Therefore, the adhesion between the base electrode layer 32 and the plating layer 34 is reduced, so that the base electrode layer 32 and the plating layer 34 formed thereon are promoted to peel off. Therefore, when the multilayer ceramic capacitor 10 is subjected to an impact when dropped or an impact of a thermal cycle, the base electrode layer 32 and the plating layer 34 can be stably peeled off, and stress can be released. As a result, cracks can be suppressed from being generated in the laminated body 12 of the multilayer ceramic capacitor 10. In addition, in the present invention, the degree of freedom in designing the laminate 12 can be improved in accordance with the thickness of the thermosetting resin layer as in Patent Document 1, and thus a higher capacitance can be achieved as a laminated ceramic capacitor.

[0132] Here, the presence of the fatty acid 40 on the surface of the base electrode layer 32 specifically means that the fatty acid 40 is dispersed on the surface of the base electrode layer 32. The fatty acids 40 dispersed on the surface of the base electrode layer 32 exist as independent layers.

[0133] The ratio of the area where the fatty acid 40 exists to the surface area of ​​the base electrode layer 32 is preferably 40% or more and 70% or less on each surface of the external electrode 30. Thus, while ensuring that the peeling between the base electrode layer 32 and the plating layer 34 of the present invention is promoted, the close contact between the base electrode layer 32 and the plating layer 34 can also be ensured.

[0134] The ratio of the area where the fatty acid 40 exists to the area of ​​the surface of the base electrode layer 32 can be calculated using TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry). Specifically, it is calculated as follows.

[0135] That is, first, Figure 7 as well as Figure 8 The following state is shown: only the first external electrode 30a of the multilayer ceramic capacitor 10 is mounted on the mounting substrate 100 using the solder 110, and the second external electrode 30b is suspended. Then, the suspended second external electrode 30b is pressed in the height direction from the lower surface, and the base electrode layer 32 and the plating layer 34 are peeled off at the first external electrode 30a mounted on one side of the mounting substrate 100. Alternatively, the following state may be set: the second external electrode 30b is mounted on the mounting substrate 100, and the first external electrode 30a is suspended.

[0136] The side surface of the peeled base electrode layer 32, that is, the entire base electrode layer 32 mounted on the land electrode 102 of the mounting substrate 100, was irradiated with primary ions (Bi3 ＋＋ ), and confirm the detection of secondary ions corresponding to fatty acid 40. Here, the secondary ions corresponding to fatty acid 40 include, for example, the following: if it is palmitic acid, C 16 H 29 O2 － , if it is oleic acid, then C 18 H 33 O2 － Then, these mapping images are acquired, and the area ratio of the region where the secondary ions corresponding to the fatty acid 40 are detected is binarized by, for example, image analysis software to calculate the area ratio. For example, imageJ or the like can be used as the image analysis software.

[0137] In addition, as a method for detecting fatty acids, TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) was used.

[0138] That is, first, Figure 7 as well as Figure 8 The following state is shown: only the first external electrode 30a of the multilayer ceramic capacitor 10 is mounted on the mounting substrate 100 using the solder 110, and the second external electrode 30b is suspended. Then, the suspended second external electrode 30b is pressed in the height direction from the lower surface, and the base electrode layer 32 and the plating layer 34 are peeled off at the first external electrode 30a mounted on one side of the mounting substrate 100. Alternatively, the following state may be set: the second external electrode 30b is mounted on the mounting substrate 100, and the first external electrode 30a is suspended.

[0139] Then, the entire surface of the exposed base electrode layer 32 mounted on the land electrode 102 was irradiated with primary ions (Bi3 ＋＋ ), and confirm the detection of secondary ions corresponding to fatty acid 40. Here, the secondary ions corresponding to fatty acid 40 include, for example, the following: if it is palmitic acid, C 16 H 29 O2 － , if it is oleic acid, then C 18 H 33 O2 － Etc. When secondary ions corresponding to the fatty acid 40 are detected, it is determined that the fatty acid 40 is present.

[0140] In addition, if Fig. 9As shown, the fatty acid 40 is preferably present on the surface of the laminate 12 between the first external electrode 30a and the second external electrode 30b. More specifically, it is preferably present on the surface of the laminate 12 so that the front end 38 of the plating layer 34 located on at least any one of the first main surface 12a and the second main surface 12b and the first side surface 12c and the second side surface 12d is in contact with the surface of the fatty acid 40, and the fatty acid 40 is present on the surface of the laminate 12 between the first external electrode 30a and the second external electrode 30b. As a result, a buffering effect is played between the laminate 12 and the plating layer 34, and a non-close contact area can be formed between the plating layer 34 and the surface of the laminate 12, and the front end 38 of the plating layer 34 becomes a floating state from the surface of the laminate 12, which can form an opportunity for peeling. Therefore, the peeling between the base electrode layer 32 and the plating layer 34 can be promoted more stably.

[0141] The fatty acid 40 is not particularly limited, and the peeling effect between the base electrode layer 32 and the plating layer 34 can be obtained regardless of whether it is a fatty acid with a small number of carbon atoms per molecule (in this example, the carbon atoms are 6 or less) such as butyric acid, valeric acid, caproic acid, or a fatty acid with a large number of carbon atoms per molecule (in this example, 26 or more) such as cerotic acid, montanic acid, and melissic acid. On the other hand, the smaller the number of carbon atoms, the shorter the length of the molecule becomes, so the thickness of the fatty acid 40 becomes thinner, and it is difficult to obtain the peeling effect. In addition, the larger the number of carbon atoms, the more the molecules of the fatty acid are entangled with each other, so the film is easy to become continuous, and when the fatty acid 40 is formed, it is not easy to form Figure 2 In order to obtain a certain peeling effect and ensure bonding stability between the base electrode layer 32 and the plating layer 34, it is particularly preferred that the number of carbon atoms per molecule is about 15, such as palmitic acid, oleic acid, stearic acid, and myristic acid, among fatty acids.

[0142] The relative intensity of secondary ions on the surface of the laminate 12 on the base electrode layer 32 or between the first external electrode 30a and the second external electrode 30b is preferably 8.07×10 －5 Above and 1.27×10 －3 As a result, the fatty acid 40 significantly inhibits the adhesion between the base electrode layer 32 and the plating layer 34, and peeling is easily caused, so that the bending strength of the substrate can be improved.

[0143] In addition, regarding the relative intensity of secondary ions derived from the fatty acid 40 on the surface on the base electrode layer 32 , the intensity derived from the fatty acid 40 was measured.

[0144] Furthermore, regarding the relative intensity of secondary ions on the surface of the stacked body 12 between the first external electrode 30 a and the second external electrode 30 b , the intensity derived from the fatty acid 40 was measured.

[0145] The relative intensity of secondary ions on the surface above the base electrode layer 32 can be measured by the following method.

[0146] That is, first, Figure 7 as well as Figure 8 As shown in the figure, the following state is set: only the first external electrode 30a of the multilayer ceramic capacitor is mounted on the mounting substrate 100 using the solder 110, and the second external electrode 30b is suspended. Then, the suspended second external electrode 30b is pressed from the lower surface in the height direction, and the base electrode layer 32 and the plating layer 34 are peeled off in the first external electrode 30a mounted on one side of the mounting substrate 100. Alternatively, the following state may be set: the second external electrode 30b is mounted on the mounting substrate 100, and the first external electrode 30a is suspended.

[0147] Then, the entire surface of the exposed base electrode layer 32 mounted on the land electrode 102 was irradiated with primary ions (Bi3 ＋＋ ), and confirm the detection of secondary ions corresponding to fatty acids. Here, the so-called secondary ions corresponding to fatty acids can be listed as follows: if it is palmitic acid, then C 16 H 29 O2 － , if it is oleic acid, then C 18 H 33 O2 － etc. Here, the relative intensity is determined from the secondary ion intensity derived from fatty acids relative to the total of all secondary ion intensities detected.

[0148] The secondary ion relative intensity on the surface of the stacked body 12 between the first external electrode 30 a and the second external electrode 30 b can be measured by the following method.

[0149] That is, first, primary ions (Bi3 ＋＋ ), and confirm the detection of secondary ions corresponding to fatty acids. Here, the so-called secondary ions corresponding to fatty acids can be listed as follows: if it is palmitic acid, then C 16 H 29 O2 － , if it is oleic acid, then C 18 H 33 O2 －Here, the relative intensity is calculated from the secondary ion intensity derived from the fatty acid relative to the total of all detected secondary ion intensities. Finally, the average value of the four locations is taken as the secondary ion relative intensity on the surface of the stack 12 .

[0150] The carbon content in the surface on the base electrode layer is preferably 74 atom% or more and 82 atom% or less. In addition, similarly, the carbon content in the surface of the laminate 12 between the first external electrode 30a and the second external electrode 30b is preferably 74 atom% or more and 82 atom% or less. As a result, the exposure amount of the metal portion bonded to the plating layer 34 can be fully suppressed, and the close contact area between the base electrode layer 32 and the plating layer 34 can be reduced. Therefore, the close contact force between the base electrode layer 32 and the plating layer 34 is reduced, so the effect of promoting the peeling of the base electrode layer 32 and the plating layer 34 formed thereon can be fully exerted.

[0151] The amount of carbon components derived from the fatty acid 40 on the surface of the base electrode layer 32 can be measured by the following method.

[0152] That is, XPS (X-ray photoelectron spectroscopy) is used for quantification. Figure 7 as well as Figure 8 As shown in the figure, the following state is set: only the first external electrode 30a of the multilayer ceramic capacitor 10 is mounted on the mounting substrate 100 using the solder 110, and the second external electrode 30b is suspended. Then, the suspended second external electrode 30b is pressed from the lower surface in the height direction, and the base electrode layer 32 and the plating layer 34 are peeled off in one external electrode 30 mounted on one side of the mounting substrate 100. Alternatively, the following state may be set: the second external electrode 30b is mounted on the mounting substrate 100, and the first external electrode 30a is suspended.

[0153] Then, the entire surface of the exposed base electrode layer 32 mounted on the land electrode 102 was irradiated with X-rays. The accelerating voltage of the thermal electrons at this time was set to 15 kV. After the qualitative analysis of all elements was performed by wide-width scanning, the abundance ratio (atom%) of all elements was quantified by narrow-width scanning, so that the carbon content of the fatty acid 40 in the surface on the base electrode layer 32 could be calculated.

[0154] The amount of carbon components derived from the fatty acid 40 on the surface of the stacked body 12 between the first external electrode 30 a and the second external electrode 30 b can be measured by the following method.

[0155] That is, in the quantification, XPS (X-ray photoelectron spectroscopy) is used. In addition, X-rays accelerated at 15 kV are irradiated at four locations, namely, the first main surface 12a, the second main surface 12b, the first side surface 12c, and the central portion of the second side surface 12d of the laminated ceramic capacitor 10. After the qualitative analysis of all elements is performed by wide-width scanning, the existence ratio (atom%) of all elements is quantified by narrow-width scanning, so that the carbon content of the fatty acid 40 in the surface of the laminate 12 originating from the base electrode layer 32 or between the first external electrode 30a and the second external electrode 30b can be calculated. Finally, the average value of the four locations is taken as the carbon content in the surface of the laminate 12.

[0156] The thickness of each layer of fatty acid dispersed on the surface of the base electrode layer 32 and the surface of the laminate 12 is preferably 10 nm to 500 nm, more preferably 50 nm to 200 nm, and even more preferably 60 nm to 100 nm.

[0157] The thickness of fatty acid 40 is measured by scanning electron microscope (SEM) image analysis of the cross section of multilayer ceramic capacitor 10 .

[0158] The thickness of the fatty acid 40 located on the base electrode layer 32 is measured in the following manner. Fig. 10(A) is a schematic cross-sectional view showing the thickness of the fatty acid located on the base electrode layer.

[0159] That is, as shown in FIG. 10 (A), the central portion of the external electrode 30 located on one side of the first main surface 12a of the multilayer ceramic capacitor 10, the central portion of the external electrode 30 located on one side of the second main surface 12b, the central portion of the external electrode 30 located on one side of the first side 12c, and the central portion of the external electrode 30 located on one side of the second side 12d are cut at an angle of 45 degrees using a converged ion beam (FIB) device. After processing to a depth at which the cross section between the base electrode layer 32 and the plating layer 34 can be confirmed, an SEM image is obtained. A secondary electron image (5 kV) is obtained at a magnification of 10,000 times. In addition, FIG. 10 (A) shows the central portion of the first external electrode 30a located on the first main surface 12a. Here, in the fatty acid 40 existing at the interface between the base electrode layer 32 and the plating layer 34, a point a1 at the boundary between the plating layer 34 and the fatty acid 40 and a point b1 at the interface between the base electrode layer 32 and the fatty acid 40 are taken at four locations, and the distance in the thickness direction of the two points is measured, thereby measuring the thickness of the fatty acid 40. Finally, the average value is taken as the thickness of the fatty acid 40.

[0160] Next, the thickness of the fatty acid 40 on the surface of the laminate 12 is specifically measured as follows. Fig. 10(B) is a schematic cross-sectional view showing the method for measuring the thickness of the fatty acid on the surface of the laminate.

[0161] That is, as shown in FIG. 10 (B), the entire surface of the multilayer ceramic capacitor 10 is coated with Au using a sputtering device to form an Au coating layer 50. First, after sputtering at a discharge current of 30 mA for 5 minutes, the surface to be measured is cut at an angle of 45 degrees using a converged ion beam (FIB) device at four locations, namely, the first main surface 12a, the second main surface 12b, the first side surface 12c, and the central part of the second side surface 12d of the multilayer ceramic capacitor 10. After processing to a depth at which a cross section can be confirmed between the sputtered Au coating layer 50 and the surface of the stack 12, an SEM image is obtained. A secondary electron image (5 kV) is obtained at a magnification of 10,000 times. In addition, FIG. 10 (B) shows the central part of the first main surface 12a of the stack 12. Here, the thickness of the fatty acid 40 is measured by measuring the distance in the thickness direction between the point a2 at the interface between the Au coating layer 50 and the fatty acid 40 and the point b2 at the interface between the surface of the laminate 12 and the fatty acid 40 at four locations respectively. Finally, the average value is taken as the thickness of the fatty acid 40.

[0162] Furthermore, the carbon content of the fatty acid 40 disposed on the base electrode layer 32 and the carbon content of the fatty acid 40 disposed on the surface of the laminate 12 disposed between the first external electrode 30a and the second external electrode 30b may be different. In this case, the carbon content of the fatty acid 40 disposed on the base electrode layer 32 is preferably greater than the carbon content of the fatty acid 40 disposed on the surface of the laminate 12 disposed between the first external electrode 30a and the second external electrode 30b. This can easily cause the base electrode layer 32 and the plating layer 34 formed thereon to peel off.

[0163] Similarly, the relative intensity of secondary ions of the fatty acid 40 disposed on the base electrode layer 32 and the relative intensity of secondary ions of the fatty acid 40 disposed on the surface of the stacked body 12 disposed between the first external electrode 30a and the second external electrode 30b may be different. In this case, the relative intensity of secondary ions of the fatty acid 40 disposed on the base electrode layer 32 is preferably greater than the relative intensity of secondary ions of the fatty acid 40 disposed on the surface of the stacked body 12 disposed between the first external electrode 30a and the second external electrode 30b.

[0164] In addition, if Fig.11As shown, a conductive resin layer 36 may be provided on the base electrode layer 32. The conductive resin layer 36 is disposed on the base electrode layer 32 and contains a resin component and a metal component. Thus, even when the multilayer ceramic capacitor 10 is subjected to a large impact during a drop or a thermal cycle, not only the electrode peeling effect of the fatty acid 40 can be obtained, but also the stress absorption function of the resin component contained in the conductive resin layer 36 and the sacrificial destruction effect in the resin component contained in the conductive resin layer 36 can be obtained, and the effect of the present invention can be made more significant.

[0165] The conductive resin layer 36 includes a first conductive resin layer 36 a and a second conductive resin layer 36 b .

[0166] The first conductive resin layer 36 a is disposed on the first foundation electrode layer 32 a . Preferably, the first conductive resin layer 36 a is disposed so as to cover the first foundation electrode layer 32 a , and an end portion of the first conductive resin layer 36 a is in contact with the laminate 12 .

[0167] The second conductive resin layer 36 b is disposed on the second foundation electrode layer 32 b. Preferably, the second conductive resin layer 36 b is disposed so as to cover the second foundation electrode layer 32 b, and the end of the second conductive resin layer 36 b is in contact with the laminate 12 .

[0168] Since the conductive resin layer 36 contains a thermosetting resin as a resin component, it is more flexible than the base electrode layer 32 composed of, for example, a plated film or a fired product of a metal component and a glass component. Therefore, even when a bending stress is applied to the mounting substrate and a physical shock or a shock caused by a thermal cycle is applied to the multilayer ceramic capacitor 10, the conductive resin layer 36 functions as a buffer layer and can prevent the multilayer ceramic capacitor 10 from cracking.

[0169] As the thermosetting resin of the conductive resin layer 36, various known thermosetting resins such as epoxy resin, phenolic resin, phenolic resin, polyurethane resin, silicone resin, and polyimide resin can be used. Among them, epoxy resin is one of the most suitable resins because of its excellent heat resistance, moisture resistance, and adhesion.

[0170] In addition, it is preferable that a curing agent is contained together with the thermosetting resin in the conductive resin layer 36. When an epoxy resin is used as the base resin, various known compounds such as phenolic, amine, acid anhydride, imidazole, active ester, and amide-imide can be used as the curing agent for the epoxy resin.

[0171] The metal component contained in the conductive resin layer 36 is preferably a metal filler, and preferably contains Ag. It can be a single substance of Ag, or an alloy containing Ag, or a metal powder coated with Ag on the surface of the metal powder. When using a metal powder coated with Ag on the surface of the metal powder, it is preferred to use Cu, Ni, Sn, Bi or their alloy powders as the metal powder. The reason for using Ag as a metal filler is that Ag has the lowest resistivity among metals and is suitable for electrode materials. Ag is a precious metal, so it is non-oxidizable and has high weather resistance. In addition, it is possible to make the metal of the base material a cheap metal while maintaining the above-mentioned characteristics of Ag.

[0172] The shape of the metal filler contained in the conductive resin layer 36 is not particularly limited. The metal filler may be spherical, flat, etc. In addition, spherical metal powder and flat metal powder may be mixed.

[0173] The average particle size of the metal filler contained in the conductive resin layer 36 is not particularly limited. The average particle size of the metal filler may be, for example, approximately 0.3 μm or more and 10 μm or less.

[0174] The average particle size of the metal filler contained in the conductive resin layer 36 can be calculated by using a laser diffraction particle size measurement method in accordance with ISO13320, regardless of the shape of the filler.

[0175] The metal fillers included in the conductive resin layer 36 are mainly responsible for the electrical conductivity of the conductive resin layer 36. Specifically, the metal fillers are in contact with each other, thereby forming an electrical conduction path inside the conductive resin layer 36.

[0176] The thickness of the conductive resin layer 36 is preferably about 10 μm or more and 200 μm or less, for example.

[0177] In addition, even when the conductive resin layer 36 is provided on the base electrode layer 32, the fatty acid 40 may be present on the surface of the laminate 12 between the first external electrode 30a and the second external electrode 30b. More specifically, the fatty acid 40 may be present on the surface of the laminate 12 so that the front end portion 38 of the plating layer 34 located on at least any one of the first main surface 12a and the second main surface 12b and the first side surface 12c and the second side surface 12d is in contact with the surface of the fatty acid 40, and the fatty acid 40 is present on the surface of the laminate 12 between the first external electrode 30a and the second external electrode 30b.

[0178] Next, refer to Figure 2 as well as Figure 3 The first plating layer 34 a and the second plating layer 34 b as the plating layer 34 disposed on the base electrode layer 32 will be described.

[0179] The first plating layer 34 a and the second plating layer 34 b include at least one selected from, for example, Cu, Ni, Sn, Ag, Pd, an Ag—Pd alloy, Au, and the like.

[0180] The first plating layer 34a is arranged to cover the first foundation electrode layer 32a.

[0181] The second plating layer 34b is arranged to cover the second foundation electrode layer 32b.

[0182] The first plating layer 34a and the second plating layer 34b may also be formed of a plurality of layers. In this case, the plating layer 34 is preferably a two-layer structure of a lower plating layer (Ni plating layer) formed on the base electrode layer 32 by plating Ni and an upper plating layer (Sn plating layer) formed on the lower plating layer by plating Sn.

[0183] That is, the first plating layer 34 a includes a first lower plating layer and a first upper plating layer located on the surface of the first lower plating layer.

[0184] Furthermore, the second plating layer 34 b includes a second lower plating layer and a second upper plating layer located on the surface of the second lower plating layer.

[0185] The lower plating layer formed by Ni plating is used to prevent the base electrode layer 32 from being corroded by the solder when mounting the multilayer ceramic capacitor 10, and the upper plating layer formed by Sn plating is used to improve the wettability of the solder when mounting the multilayer ceramic capacitor 10 so that it can be mounted easily.

[0186] The thickness of each plating layer is preferably 2.0 μm or more and 15.0 μm or less.

[0187] Furthermore, when the conductive resin layer 36 is formed on the base electrode layer 32 , the plating layer 34 is arranged so as to cover the conductive resin layer 36 .

[0188] The dimension of the multilayer ceramic capacitor 10 including the stack 12, the first external electrode 30a and the second external electrode 30b in the length direction z is set to L dimension, the dimension of the multilayer ceramic capacitor 10 including the stack 12, the first external electrode 30a and the second external electrode 30b in the height direction x is set to T dimension, and the dimension of the multilayer ceramic capacitor 10 including the stack 12, the first external electrode 30a and the second external electrode 30b in the width direction y is set to W dimension.

[0189] Regarding the dimensions of the multilayer ceramic capacitor 10, the L dimension in the length direction z is greater than or equal to 0.2 mm and less than or equal to 10.0 mm, the W dimension in the width direction y is greater than or equal to 0.1 mm and less than or equal to 10.0 mm, and the T dimension in the height direction x is greater than or equal to 0.1 mm and less than or equal to 10.0 mm. The dimensions of the multilayer ceramic capacitor 10 can be measured using a microscope.

[0190] exist Figure 1 In the illustrated multilayer ceramic capacitor 10, the fatty acid 40 is present at least on the surface of the first base electrode layer 32a and the surface of the second base electrode layer 32b, so that the carboxyl group of the fatty acid is ionized and adsorbed to the base electrode layer 32 by ionic bonding force, and the deposition of the plating of the plating layer 34 provided on the base electrode layer 32 is inhibited at the adsorbed portion, and the bonding area between the base electrode layer 32 and the plating layer 34 can be reduced. Therefore, the adhesion between the base electrode layer 32 and the plating layer 34 is reduced, and the peeling of the base electrode layer 32 and the plating layer 34 formed thereon is promoted.

[0191] Therefore, when the multilayer ceramic capacitor 10 is subjected to impact during a drop or thermal cycle, the base electrode layer 32 and the plating layer 34 can be stably separated and stress can be released. As a result, cracks in the laminated body 12 of the multilayer ceramic capacitor 10 can be suppressed.

[0192] In addition, Figure 1 In the illustrated multilayer ceramic capacitor 10 , when the conductive resin layer 36 is not provided on the external electrode 30 , not only the cost can be reduced, but also the degree of freedom in designing the multilayer body 12 increases according to the thickness of the conductive resin layer 36 , thereby achieving a higher capacitance.

[0193] 2. Manufacturing method of multilayer ceramic capacitor

[0194] Next, a method for manufacturing a multilayer ceramic capacitor will be described.

[0195] First, a dielectric sheet for a ceramic layer and a conductive paste for an internal electrode layer are prepared. The dielectric sheet and the conductive paste for the internal electrode layer contain a binder and a solvent. The binder and the solvent may be known binders and solvents.

[0196] Then, conductive paste for the internal electrode layer is printed in a predetermined pattern on the dielectric sheet by screen printing, gravure printing, etc. Thus, a dielectric sheet having a pattern of the first internal electrode layer and a dielectric sheet having a pattern of the second internal electrode layer are prepared.

[0197] In addition, regarding the dielectric sheet, a dielectric sheet for an outer layer on which the pattern of the internal electrode layer is not printed is also prepared.

[0198] Next, a predetermined number of dielectric sheets for outer layers on which the pattern of the internal electrode layer is not printed are stacked, thereby forming a portion of the second main surface side outer layer portion. Then, a dielectric sheet on which the pattern of the first internal electrode layer is printed and a dielectric sheet on which the pattern of the second internal electrode layer is printed are sequentially stacked on the portion of the second main surface side outer layer portion to form the structure of the present invention, thereby forming a portion of the inner layer portion. A predetermined number of dielectric sheets for outer layers on which the pattern of the internal electrode layer is not printed are stacked on the portion of the inner layer portion, thereby forming a portion of the first main surface side outer layer portion on the first main surface side.

[0199] Next, the laminated sheets are pressed in the laminating direction by isostatic pressing or the like, thereby producing a laminated block.

[0200] Then, the stacked block is cut into a given size to cut out stacked small pieces. At this time, the corners and ridges of the stacked small pieces may be rounded by barrel grinding or the like.

[0201] Next, the stacked small pieces are fired to produce the stacked body 12. The firing temperature depends on the materials of the ceramic layers and internal electrode layers as dielectrics, but is preferably 900°C or higher and 1400°C or lower.

[0202] Next, a conductive paste to be a base electrode layer is applied to the first end face and the second end face of the laminate to form a base electrode layer. When a sintered layer is formed as the base electrode layer, a conductive paste containing a glass component and a metal is applied by a method such as dipping, and then sintered to form the base electrode layer. The temperature of the sintering treatment at this time is preferably 700° C. or higher and 950° C. or lower.

[0203] When the base electrode layer is formed of a sintered layer, the sintered layer may contain a ceramic component. In this case, the sintered layer may contain a ceramic component instead of a glass component, or may contain both.

[0204] The ceramic component is preferably a ceramic material of the same type as the laminate. In addition, when the sintered layer contains a ceramic component, it is preferred that a conductive paste is applied to the pre-sintered laminated small pieces, and the pre-sintered laminated small pieces and the conductive paste applied to the pre-sintered laminated small pieces are simultaneously sintered (fired) to form a laminate, and the laminate forms a sintered layer. The temperature of the sintering treatment (sintering temperature) at this time is preferably 900° C. or more and 1400° C. or less.

[0205] Next, a layer dispersed with fatty acids is formed on the base electrode layer. As a method for forming a layer dispersed with fatty acids on the base electrode layer, the fatty acids can be diluted with an organic solvent and immersed in a solution. Specifically, for example, a solution of oleic acid diluted with IPA (2-propanol) is prepared. The laminate forming the base electrode layer is placed in a mesh cage and immersed in the solution for a given time (for example, 5 minutes). Then, the mesh cage is taken out of the solution and the liquid is removed for a given time (for example, 30 seconds), and the laminate forming the base electrode layer is spread on filter paper and heat-treated in an oven at 150°C for a given time (for example, 30 minutes) to solidify the fatty acid.

[0206] Alternatively, the formation may be performed by diluting a fatty acid with an organic solvent to prepare a solution, applying the solution to the laminate having the base electrode layer formed thereon, and thermally curing the solution. The solution may be applied by dipping, spraying, or the like.

[0207] In addition, the relative intensity of secondary ions of fatty acids, the amount of carbon components, the ratio of the area where fatty acids exist to the base electrode layer, and the thickness of fatty acids can be controlled by controlling the solution concentration, coating method, coating time, and coating temperature.

[0208] (When a conductive resin layer is provided)

[0209] When a conductive resin layer is provided as an external electrode, it is formed as follows.

[0210] The conductive resin layer is formed on the base electrode layer.

[0211] As a method for forming a conductive resin layer, a conductive resin paste containing a resin component and a metal component is prepared and applied to the base electrode layer by a dipping method. Then, a heat treatment is performed at a temperature of 200° C. to 550° C. to thermally cure the resin, thereby forming a conductive electrode layer.

[0212] The atmosphere during the heat treatment at this time is preferably a N2 atmosphere.

[0213] Furthermore, in order to prevent scattering of the resin and oxidation of various metal components, the oxygen concentration is preferably suppressed to 100 ppm or less.

[0214] Next, a plating layer is formed on the surface of the base electrode layer. In more detail, a Ni plating layer is formed on the base electrode layer, and a Sn plating layer is formed on the Ni plating layer. When performing the plating process, either electrolytic plating or electroless plating can be used. However, electroless plating requires pretreatment with a catalyst or the like in order to increase the plating deposition rate, which has the disadvantage of complicating the process. Therefore, electrolytic plating is generally preferred. In addition, when a conductive resin layer is formed, a plating layer is formed on the surface of the conductive resin layer.

[0215] As described above, the multilayer ceramic capacitor 10 according to the present embodiment is manufactured.

[0216] 3. Experimental Examples

[0217] According to the above-mentioned manufacturing method, a sample of a laminated ceramic capacitor as a laminated ceramic electronic component was prepared, and in order to evaluate the effect of forming the fatty acid, a bending strength test was performed to confirm the presence or absence of cracks formed in the laminated body, thereby evaluating the effect.

[0218] (a) Specifications of the sample of Example 1

[0219] As Example 1, a multilayer ceramic capacitor having the following specifications was prepared.

[0220] That is, regarding the multilayer ceramic capacitor of Example 1, a sample of the multilayer ceramic capacitor was prepared as follows: Figure 2 As shown, a fatty acid is made to exist on the base electrode layer, and a Ni plating layer is formed so that the base electrode layer including the fatty acid is covered, and further a Sn plating layer is formed on the Ni plating layer.

[0221] ・Dimensions of multilayer ceramic capacitors (design values): L×W×T=1.0mm×0.5mm×0.5mm

[0222] ·Main component material of ceramic layer: BaTiO3

[0223] Capacitance: 10nF

[0224] Internal electrode material: Ni

[0225] Specifications of external electrode layer

[0226] Specifications of base electrode layer

[0227] Base electrode layer: a sintered layer containing metal components and glass components

[0228] Metal composition: Cu

[0229] Thickness of the base electrode layer

[0230] Thickness in the length direction z at the center of the base electrode layer in the height direction x located at the first end face and the second end face in the cross section of the laminate at the 1 / 2W position: 28 μm

[0231] Thickness in the height direction x connecting the first and second principal surfaces at the center of the base electrode layer in the length direction z of the cross section of the laminate at the 1 / 2W position (thickness of the base electrode layer in the center of the e-inch): 10 μm

[0232] Thickness in the width direction y connecting the first side and the second side at the center of the base electrode layer in the length direction z of the cross section of the stack at the 1 / 2T position (thickness of the base electrode layer in the center of the length): 10 μm

[0233] Specification of fatty acid: Oleic acid was diluted with 2-propanol and impregnated only part of the base electrode layer for 5 minutes, then the small piece was laid on an aluminum refractory brick sheet and cured in an oven (150°C for 30 minutes).

[0234] · Ratio of the area where the fatty acid exists to the area of ​​the surface of the base electrode layer: 55% (so that the design is the same on all surfaces.)

[0235] Secondary ion relative intensity: 6.75×10 －4

[0236] Carbon content: 80atom%

[0237] · The position of fatty acid is set: only on the surface of the base electrode layer

[0238] Specifications of the plating layer: It is formed of two layers, a Ni plating layer is formed on the base electrode layer on which the fatty acid is arranged, and a Sn plating layer is formed on the Ni plating layer.

[0239] ·Ni plating layer thickness: 3.5μm

[0240] ·Sn plating layer thickness: 3.0μm

[0241] (b) Specifications of the sample of Example 2

[0242] As Example 2, a multilayer ceramic capacitor having the following specifications was prepared.

[0243] That is, regarding the multilayer ceramic capacitor of Example 2, a sample of the multilayer ceramic capacitor was prepared as follows: Fig. 9As shown, the fatty acid is not only present on the base electrode layer, but also on the surface of the stacked body, so that the surface of the stacked body located between the first external electrode and the second external electrode, more specifically, the front end of the plating layer located on the surface of the first main surface and the second main surface and the first side surface and the second side surface is in contact with the surface of the fatty acid, and the fatty acid is present on the surface of the stacked body between the first external electrode and the second external electrode, and a Ni plating layer is formed as the plating layer, so that the base electrode layer is covered with the fatty acid, and a Sn plating layer is formed on the Ni plating layer.

[0244] ・Dimensions of multilayer ceramic capacitors (design values): L×W×T=1.0mm×0.5mm×0.5mm

[0245] ·Main component material of ceramic layer: BaTiO3

[0246] Capacitance: 10nF

[0247] Internal electrode material: Ni

[0248] Specifications of external electrode layer

[0249] Specifications of base electrode layer

[0250] Base electrode layer: a sintered layer containing metal components and glass components

[0251] Metal composition: Cu

[0252] Thickness of the base electrode layer

[0253] Thickness in the length direction z at the center of the base electrode layer in the height direction x located at the first end face and the second end face in the cross section of the laminate at the 1 / 2W position: 28 μm

[0254] Thickness in the height direction x connecting the first and second principal surfaces at the center of the base electrode layer in the length direction z of the cross section of the laminate at the 1 / 2W position (thickness of the base electrode layer in the center of the e-inch): 10 μm

[0255] Thickness in the width direction y connecting the first side and the second side at the center of the base electrode layer in the length direction z of the cross section of the stack at the 1 / 2T position (thickness of the base electrode layer in the center of the length): 10 μm

[0256] Specifications of fatty acid: Oleic acid was diluted with 2-propanol and the entire laminate having the base electrode layer was immersed for 5 minutes. The small pieces were then placed on aluminum refractory bricks and cured in an oven (150°C for 30 minutes).

[0257] · Ratio of the area where the fatty acid exists to the area of ​​the surface of the base electrode layer: 55% (so that the design is the same on all surfaces.)

[0258] Secondary ion relative intensity: 6.75×10 －4

[0259] Carbon content: 80atom%

[0260] · Locations where fatty acids are provided: On the base electrode layer and on the surface of the laminate between the external electrodes

[0261] Specifications of the plating layer: It is formed of two layers, a Ni plating layer is formed on the base electrode layer on which the fatty acid is arranged, and a Sn plating layer is formed on the Ni plating layer.

[0262] ·Ni plating layer thickness: 3.5μm

[0263] ·Sn plating layer thickness: 3.0μm

[0264] (c) Specifications of the sample of Example 3

[0265] As Example 3, a multilayer ceramic capacitor having the following specifications was prepared.

[0266] That is, regarding the multilayer ceramic capacitor of Example 3, a sample of the multilayer ceramic capacitor was prepared as follows: Fig. 9 As shown, the fatty acid is not only present on the base electrode layer, but also on the surface of the stacked body, so that the surface of the stacked body located between the first external electrode and the second external electrode, more specifically, the front end of the plating layer located on the surface of the first main surface and the second main surface and the first side surface and the second side surface contacts the surface of the fatty acid, and the fatty acid is present on the surface of the stacked body between the first external electrode and the second external electrode, a conductive resin layer having a metal component and a thermosetting resin component is formed, and a Ni plating layer is formed as the plating layer, so that the conductive resin layer including the fatty acid is covered, and a Sn plating layer is formed on the Ni plating layer.

[0267] ・Dimensions of multilayer ceramic capacitors (design values): L×W×T=1.0mm×0.5mm×0.5mm

[0268] ·Main component material of ceramic layer: BaTiO3

[0269] Capacitance: 10nF

[0270] Internal electrode material: Ni

[0271] Specifications of external electrode layer

[0272] Specifications of base electrode layer

[0273] Base electrode layer: a sintered layer containing metal components and glass components

[0274] Metal composition: Cu

[0275] Thickness of the base electrode layer

[0276] Thickness in the length direction z at the center of the base electrode layer in the height direction x located at the first end face and the second end face in the cross section of the laminate at the 1 / 2W position: 28 μm

[0277] Thickness in the height direction x connecting the first and second principal surfaces at the center of the base electrode layer in the length direction z of the cross section of the laminate at the 1 / 2W position (thickness of the base electrode layer in the center of the e-inch): 10 μm

[0278] Thickness in the width direction y connecting the first side and the second side at the center of the base electrode layer in the length direction z of the cross section of the stack at the 1 / 2T position (thickness of the base electrode layer in the center of the length): 10 μm

[0279] Specifications of fatty acid: Oleic acid was diluted with 2-propanol and the entire laminate having the base electrode layer was immersed for 5 minutes. The small pieces were then placed on aluminum refractory bricks and cured in an oven (150°C for 30 minutes).

[0280] · Ratio of the area where the fatty acid exists to the area of ​​the surface of the base electrode layer: 55% (so that the design is the same on all surfaces.)

[0281] Secondary ion relative intensity: 6.75×10 －4

[0282] Carbon content: 80atom%

[0283] · Locations where fatty acids are provided: On the base electrode layer and on the surface of the laminate between the external electrodes

[0284] ·Conductive resin layer specifications

[0285] Metal composition: Cu coated with Ag

[0286] ·Thermosetting resin component: Epoxy

[0287] Thickness in the length direction z at the center of the conductive resin layer in the height direction x located at the first end face and the second end face in the cross section of the laminate at the 1 / 2W position: 25 μm

[0288] Thickness in the height direction x connecting the first and second main surfaces at the center of the length direction z of the conductive resin layer located on the first and second main surfaces in the cross section of the laminate at the 1 / 2W position (thickness of the base electrode layer in the center of the length direction e): 8 μm

[0289] Thickness in the width direction y connecting the first side and the second side at the center of the length direction z of the conductive resin layer located on the first side and the second side in the cross section of the laminate at the 1 / 2T position (thickness of the base electrode layer in the center of the length direction e): 8 μm

[0290] Specifications of the plating layer: It is formed of two layers, a Ni plating layer is formed on the base electrode layer on which the fatty acid is arranged, and a Sn plating layer is formed on the Ni plating layer.

[0291] ·Ni plating layer thickness: 3.5μm

[0292] ·Sn plating layer thickness: 3.0μm

[0293] (d) Specifications of Comparative Example Samples

[0294] As a comparative example, a laminated ceramic capacitor was prepared in which the process of forming fatty acid on the base electrode layer was not performed, that is, a Ni plating layer was formed on the base electrode layer, and a Sn plating layer was further formed on the Ni plating layer. Therefore, the design was set to be the same as the structure of Example 1 except that there was no fatty acid.

[0295] (e) Method for confirming the presence or absence of cracks using bending strength test

[0296] First, the multilayer ceramic capacitor as a sample was mounted on a mounting substrate with a thickness of 1.6 mm using solder paste. Then, a mechanical pressure was applied by bending the substrate from the back side of the mounting substrate on which the multilayer ceramic capacitor was not mounted using a pressure bar with a curvature radius of 1 μm. At this time, the bending amount was set to 2 mm, and it was bent for 60 seconds. In addition, in this test, conditions that are stricter than the AEC-Q200 standard required for vehicle-mounted use were set. After the substrate was bent, the multilayer ceramic capacitor was removed from the mounting substrate, cross-sectioned and ground, and the presence or absence of cracks inside the stack was observed. Regarding the cross-section grinding, the multilayer ceramic capacitor was ground until the position of 1 / 2W in the width direction y connecting the first side surface and the second side surface was reached, so that the LT surface of the multilayer ceramic capacitor was exposed. 30 samples were prepared for each of Examples 1 to 3 and the comparative example.

[0297] (f) Results

[0298] Table 1 shows the results of checking the presence or absence of cracks in the laminated body by a bending strength test for each sample of Examples 1 to 3 and Comparative Example.

[0299] [Table 1]

[0300]

[0301] According to Table 1, in the bending strength test, cracks formed inside the laminate were confirmed in 18 of 30 samples of the comparative example.

[0302] On the other hand, in the samples of Example 1, when the fatty acid was present only on the base electrode layer, cracks formed inside the laminate were confirmed in 6 of 30 samples, which was a good result compared with the samples of the comparative example.

[0303] In addition, in the samples of Example 2, when the fatty acid was present on the base electrode layer and on the surface of the laminate, cracks were confirmed to be formed inside the laminate in 4 out of 30 samples, which was a better result than the samples of Example 1.

[0304] Furthermore, in the samples of Example 3, when fatty acids were present on the base electrode layer and a conductive resin layer was provided on its surface so as to cover the base electrode layer, no cracks were confirmed to be formed inside the stack in any of the 30 samples, and better results were obtained compared with the samples of Examples 1 and 2.

[0305] According to the above results, according to the structure of the multilayer ceramic capacitor of Example 1, by making the fatty acid exist at least on the surface of the base electrode layer, the carboxyl group of the fatty acid is ionized and adsorbed to the base electrode layer by ionic bonding force, and the deposition of the plating layer provided on the base electrode layer can be hindered in the adsorption portion, and the bonding area between the base electrode layer and the plating layer can be reduced. Therefore, it is considered that the adhesion between the base electrode layer and the plating layer is reduced, so that the effect of promoting the peeling of the base electrode layer and the plating layer formed thereon is exerted.

[0306] Therefore, when the multilayer ceramic capacitor is subjected to impact during a drop or thermal cycle, the base electrode layer and the plating layer can be stably separated and stress can be released. As a result, it was confirmed that cracks can be suppressed in the multilayer body of the multilayer ceramic capacitor.

[0307] In addition, the structure of the multilayer ceramic capacitor of Example 1 does not have a thermosetting resin layer like Patent Document 1, which not only reduces costs but also increases the design freedom of the multilayer body according to the thickness of the thermosetting resin layer, thereby achieving high capacitance.

[0308] In addition, according to the structure of the multilayer ceramic capacitor of Example 2, by making the fatty acid exist on the surface of the multilayer body between the external electrodes, a buffering effect is played between the multilayer body and the plating layer, and a non-closed area can be formed between the plating layer and the surface of the multilayer body, and the front end of the plating layer becomes a floating state from the surface of the multilayer body, which can form an opportunity for peeling. Therefore, it is confirmed that the peeling between the base electrode layer and the plating layer can be promoted more stably.

[0309] Furthermore, according to the structure of the stacked ceramic capacitor of Example 3, fatty acids are present on the surface of the stacked body on the base electrode layer and between the external electrodes, and a conductive resin layer is formed to cover the base electrode layer. Therefore, the conductive resin layer functions as a buffer layer, and it is confirmed that it can further prevent the occurrence of cracks in the stacked ceramic capacitor.

[0310] Furthermore, as described above, the embodiments of the present invention have been disclosed through the above description, but the present invention is not limited thereto.

[0311] That is, various changes may be made to the above-described embodiments with respect to structure, shape, material, number, position, or arrangement without departing from the technical idea and scope of the present invention, and these are all included in the present invention.

Claims

1. A laminated ceramic electronic component comprising: A laminated body comprising a plurality of laminated ceramic layers, and having a first main surface and a second main surface opposite to each other in a height direction, a first side surface and a second side surface opposite to each other in a width direction perpendicular to the height direction, and a first end surface and a second end surface opposite to each other in a length direction perpendicular to the height direction and the width direction; a first internal electrode layer disposed on the plurality of ceramic layers and exposed at the first end surface; a second internal electrode layer disposed on the plurality of ceramic layers and exposed at the second end surface; a first external electrode electrically connected to the first internal electrode layer and arranged on the first end surface, a portion of the first main surface, a portion of the second main surface, a portion of the first side surface, and a portion of the second side surface; and a second external electrode electrically connected to the second internal electrode layer and arranged on the second end surface, a portion of the first main surface, a portion of the second main surface, a portion of the first side surface, and a portion of the second side surface; in, The first external electrode and the second external electrode include: a base electrode layer comprising a metal component; and a plating layer disposed on the base electrode layer, Fatty acids are present at least on the surface of the base electrode layer.

2. The multilayer ceramic electronic component according to claim 1, wherein A fatty acid exists on the surface of the stacked body between the first external electrode and the second external electrode.

3. The multilayer ceramic electronic component according to claim 1 or claim 2, wherein: The fatty acid includes at least one of palmitic acid, oleic acid, stearic acid, and myristic acid.

4. The multilayer ceramic electronic component according to claim 1 or claim 2, wherein: The relative intensity of secondary ions derived from fatty acids present on the base electrode layer or fatty acids present on the surface of the stacked body between the first external electrode and the second external electrode was 8.07×10 －5 Above and 1.27×10 －3 the following.

5. The multilayer ceramic electronic component according to claim 1 or claim 2, wherein: The carbon content of the fatty acid derived from the fatty acid present on the base electrode layer or the fatty acid derived from the surface of the stacked body between the first external electrode and the second external electrode is 74 atom % or more and 82 atom % or less.

6. The multilayer ceramic electronic component according to claim 1 or claim 2, wherein: A conductive resin layer including a metal component and a thermosetting resin component is disposed between the base electrode layer and the plating layer.

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