Multilayer ceramic capacitor

Abstract

Provided is a multilayer ceramic capacitor capable of reducing stress.　A base electrode layer 32 of an external electrode 30 in this multilayer ceramic capacitor 10 includes an end surface electrode part 40 and a wraparound electrode part 41 that wraps around at least one among a first main surface 12a, a second main surface 12b, a first side surface 12c, and a second side surface 12d from a first end surface 12e and a second end surface 12f. The wraparound electrode part 41 includes base end side parts 42 positioned on the first end surface 12e and the second end surface 12f sides, and tip side parts 43 positioned on the tip sides of the base end side parts 42 away from the first end surface 12e and the second end surface 12f. At least one tip-side adhesion interface 53a where a laminate 12 is adhered to the tip side parts 43, and at least one tip-side non-adhesion interface 53b where the laminate 12 is not adhered to the tip-side parts 43, are included in tip-side interfaces 53 of the laminate 12 facing the tip-side parts 43.

Description

Multilayer ceramic capacitors

[0001] The present invention relates to a multilayer ceramic capacitor.

[0002] A typical multilayer ceramic capacitor includes a laminate in which multiple ceramic layers and multiple internal electrode layers are stacked, and external electrodes formed on the outer surfaces of the laminate. The internal electrode layers are extended to the end faces of the laminate and connected to the external electrodes. The external electrodes are composed of, for example, a base electrode layer formed by firing a conductive paste applied to the laminate, and a plating layer formed on the outer surface of the base electrode layer.

[0003] In Patent Document 1, the external electrodes are formed with their tip ends (e-dimension ends) spaced apart from the laminate. Stresses such as thermal stress and tensile stress are applied to the multilayer ceramic capacitor during the solder reflow process when mounting the multilayer ceramic capacitor on a substrate, and during transportation and operation of the multilayer ceramic capacitor mounted on the substrate. In the multilayer ceramic capacitor of Patent Document 1, the tip ends of the external electrodes spaced apart from the laminate mainly absorb the stress. Therefore, the stress applied to the laminate can be alleviated more effectively than if the entire external electrodes were bonded to the laminate.

[0004] JP 2010-109238 A

[0005] However, with the configuration of Patent Document 1, the tip portions of the external electrodes that are separated from the laminate are primarily subjected to stress, resulting in a problem in that the tip portions are severely chipped. Therefore, further improvements in multilayer ceramic capacitors that can alleviate stress are desired.

[0006] SUMMARY OF THE INVENTION Therefore, a primary object of the present invention is to provide a multilayer ceramic capacitor capable of relaxing stress.

[0007] A multilayer ceramic capacitor according to the present invention comprises: a laminate including a plurality of laminated ceramic layers and a plurality of internal electrode layers, the laminate including first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, and first and second end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction; and external electrodes connected to the internal electrode layers at the first end surface and the second end surface. the external electrode includes a base electrode layer formed on the laminate, the base electrode layer including conductive particles and glass; the base electrode layer including: an end surface electrode portion formed on the laminate at the first end surface and the second end surface; and a wraparound electrode portion continuous with the end surface electrode portion and formed on the laminate by wrapping around from the first end surface and the second end surface to at least one of the first main surface, the second main surface, the first side surface, and the second side surface; the wraparound electrode portion including: a base end side portion located on the first end surface and the second end surface side; and a tip end side portion continuous with the base end side portion and located on the tip side away from the first end surface and the second end surface with respect to the base end side portion; and the tip end side interface of the laminate facing the wraparound electrode portion, facing the tip side portion, includes at least one tip end side adhesive interface where the laminate is bonded to the tip side portion, and at least one tip end side non-adhesive interface where the laminate is not bonded to the tip side portion.

[0008] The multilayer ceramic capacitor has the above-described tip side portion, and stress is less likely to accumulate in the tip side portion, making it possible to relieve stress.

[0009] According to the present invention, it is possible to provide a multilayer ceramic capacitor capable of relaxing stress.

[0010] The above and other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments of the present invention, which proceeds with reference to the accompanying drawings.

[0011] 1 is an external perspective view showing an example of a multilayer ceramic capacitor as an electronic component according to an embodiment of the present invention. It is a cross-sectional view taken along line II-II in FIG. 1 . It is a partially enlarged cross-sectional view of a base electrode layer and a laminate when a plating layer is omitted from the multilayer ceramic capacitor of FIG. 2 . It is a cross-sectional view of portion α in FIG. 3 . (a) is a result of Al detection using an EDX device from a tip side portion to a part of a base end side portion in a multilayer ceramic capacitor according to an embodiment of the present invention, and (b) is a result of Cu detection using an EDX device at the same location as in (a). (a) is a schematic diagram showing an embodiment of a base electrode layer paste according to the present embodiment, and (b) is a schematic diagram showing an embodiment of a base electrode layer paste different from that of the present embodiment. It is a schematic diagram showing a state in which the base electrode layer paste according to the present embodiment is applied to a laminate. It is an SEM image of a cross section of a part of the tip side and base end side of the present embodiment before a plating layer is formed. It is an SEM image of a cross section of a part of the tip side and base end side different from that of the present embodiment before a plating layer is formed. 9A is a result of Al detection using an EDX device from the tip side to a part of the base side shown in FIG. 9A, and FIG. 9B is a result of Cu detection using an EDX device at the same location as in FIG. 9A. It is a partially enlarged cross-sectional view of the base electrode layer and the laminate when the plating layer is omitted from the multilayer ceramic capacitor of Comparative Example 1. It is a partially enlarged cross-sectional view of the base electrode layer and the laminate when the plating layer is omitted from the multilayer ceramic capacitor of Comparative Example 2 ...

[0012] EMBODIMENTS 1. Multilayer Ceramic Capacitor A multilayer ceramic capacitor according to an embodiment of the present invention will be described below, taking a two-terminal multilayer ceramic capacitor as an example.

[0013] FIG. 1 is an external perspective view showing an example of a multilayer ceramic capacitor as an electronic component according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. FIG. 3 is a partially enlarged cross-sectional view of a base electrode layer and a laminate obtained when the plating layer is omitted from the multilayer ceramic capacitor of FIG. 2. FIG. 4 is a cross-sectional view of portion α in FIG. 3. In FIGS. 3 and 4, the multilayer ceramic capacitor 10 is exposed in a cross section perpendicular to the first and second end faces 12e, 12f. Specifically, the examples in FIGS. 3 and 4 are cross-sectional views of the multilayer ceramic capacitor 10 polished to expose the first and second end faces 12e, 12f and the first and second main faces 12a, 12b.

[0014] The laminate 12 includes a plurality of stacked ceramic layers 14 and a plurality of internal electrode layers 16. The laminate 12 further includes a first main surface 12a and a second main surface 12b that face each other in a height direction x, a first side surface 12c and a second side surface 12d that face each other in a width direction y that is perpendicular to the height direction x, and a first end surface 12e and a second end surface 12f that face each other in a length direction z that is perpendicular to the height direction x and the width direction y. The corners and ridges of the laminate 12 are preferably rounded. The corners refer to the intersections of three adjacent surfaces of the laminate 12, and the ridges refer to the intersections of two adjacent surfaces of the laminate 12. Furthermore, unevenness may be formed on some or all of 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. Furthermore, the dimension of the laminate 12 in the length direction z is not necessarily longer than the dimension in the width direction y.

[0015] The laminate 12 has, in the lamination direction x connecting the first main surface 12a and the second main surface 12b, an effective layer portion 15a where the internal electrode layers 16 face each other, a first outer layer portion 15b located between the first main surface 12a and the internal electrode layer 16 closest to the first main surface 12a, and a second outer layer portion 15c located between the second main surface 12b and the internal electrode layer 16 closest to the second main surface 12b. The first outer layer portion 15b is located on the first main surface 12a side of the laminate 12, and is an assembly of multiple ceramic layers 14 located between the first main surface 12a and the internal electrode layer 16 closest to the first main surface 12a. The second outer layer portion 15c is located on the second main surface 12b side of the laminate 12, and is an assembly of multiple ceramic layers 14 located between the second main surface 12b and the internal electrode layer 16 closest to the second main surface 12b. The region sandwiched between the first outer layer portion 15b and the second outer layer portion 15c is the effective layer portion 15a.

[0016] The dimensions of the laminate 12 are not particularly limited, but it is preferable that the dimension in the length direction z is, for example, 0.2 mm or more and 10.0 mm or less, the dimension in the width direction y is, for example, 0.1 mm or more and 10.0 mm or less, and the dimension in the height direction x is, for example, 0.1 mm or more and 5.0 mm or less.

[0017] The ceramic layer 14 can be formed, for example, from a dielectric material as the ceramic material. Such a dielectric material includes a perovskite compound represented by the general formula ABO3, in which the A site is Ba. For example, a dielectric ceramic containing a component such as BaTiO3 can be used as the dielectric material. When the dielectric material is the main component, it may also contain, for example, a Mn compound, an Fe compound, a Cr compound, a Co compound, or a Ni compound, depending on the desired properties of the laminate 12.

[0018] The number of ceramic layers 14, including the effective layer portion 15a and the first and second outer layer portions 15b, 15c, is preferably, for example, 15 to 1000.

[0019] The thickness of the ceramic layer 14 after firing is preferably, for example, 0.4 μm or more and 2 μm or less.

[0020] When a piezoelectric ceramic material is used for the ceramic layer 14, the electronic component functions as a piezoelectric component. Specific examples of piezoelectric ceramic materials include PZT (lead zirconate titanate) ceramic materials. When a semiconductor ceramic material is used for the ceramic layer 14, the electronic component functions as a thermistor element. Specific examples of semiconductor ceramic materials include spinel ceramic materials. When a magnetic ceramic material is used for the ceramic layer 14, the electronic component functions as an inductor element. When functioning as an inductor element, the internal electrode layer 16 becomes a coil-shaped conductor. Specific examples of magnetic ceramic materials include ferrite ceramic materials.

[0021] 2, the laminate 12 has, for example, a plurality of substantially rectangular first internal electrode layers 16a and a plurality of second internal electrode layers 16b as the plurality of internal electrode layers 16. The plurality of first internal electrode layers 16a and the plurality of second internal electrode layers 16b are embedded so as to be alternately arranged at equal intervals along the lamination direction of the laminate 12. The first internal electrode layers 16a and the second internal electrode layers 16b may be arranged parallel to or perpendicular to the mounting surface.

[0022] The first internal electrode layer 16a has an end portion exposed from the laminate 12 at a first end face 12e, and the second internal electrode layer 16b has an end portion exposed from the laminate 12 at a second end face 12f.

[0023] The internal electrode layers 16 contain an appropriate conductive material, such as a metal such as Ni, Cu, Ag, Pd, or Au, or an alloy containing at least one of these metals, such as an Ag-Pd alloy. The internal electrode layers 16 may further contain dielectric particles having the same composition as the ceramic contained in the ceramic layers 14.

[0024] The thickness of the internal electrode layer 16 is preferably, for example, 0.2 μm or more and 2.0 μm or less.

[0025] External electrodes 30 are disposed on the first end face 12e side and the second end face 12f side of the laminate 12. The external electrodes 30 include a first external electrode 30a and a second external electrode 30b.

[0026] The first external electrode 30a is connected to the first internal electrode layer 16a on the first end face 12e side. In this embodiment, the first external electrode 30a extends from the first end face 12e side and is disposed on a portion of the first principal surface 12a side, a portion of the second principal surface 12b side, a portion of the first side surface 12c side, and a portion of the second side surface 12d side.

[0027] The second external electrode 30b is connected to the second internal electrode layer 16b on the second end face 12f side. In this embodiment, the second external electrode 30b extends from the second end face 12f side and is disposed on a portion of the first main surface 12a side, a portion of the second main surface 12b side, a portion of the first side surface 12c side, and a portion of the second side surface 12d side.

[0028] In the laminate 12, capacitance is formed by the first internal electrode layer 16a and the second internal electrode layer 16b facing each other via the ceramic layer 14. Therefore, capacitance 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.

[0029] The external electrode 30 includes a base electrode layer 32 and a plating layer 34 formed on the base electrode layer 32 .

[0030] The base electrode layer 32 includes a first base electrode layer 32a and a second base electrode layer 32b.

[0031] The first base electrode layer 32a is connected to the first internal electrode layer 16a on the first end face 12e side of the laminate 12. In this embodiment, the first base electrode layer 32a is formed so as to extend from the first end face 12e side and cover a portion of the surface on the first main face 12a side, the second main face 12b side, the first side face 12c side, and the second side face 12d side. However, the first base electrode layer 32a may be formed so as to extend from the first end face 12e side and cover a portion of at least one of the surface on the first main face 12a side, the second main face 12b side, the first side face 12c side, and the second side face 12d side.

[0032] The second base electrode layer 32b is connected to the second internal electrode layer 16b on the second end face 12f side of the laminate 12. In this embodiment, the second base electrode layer 32b is formed so as to extend from the second end face 12f side and cover a portion of the surface on the first main face 12a side, the second main face 12b side, the first side face 12c side, and the second side face 12d side. However, the second base electrode layer 32b may be formed so as to extend from the second end face 12f side and cover a portion of at least one of the surface on the first main face 12a side, the second main face 12b side, the first side face 12c side, and the second side face 12d side.

[0033] The maximum thickness of the first and second base electrode layers 32a, 32b is preferably, for example, about 10 μm or more and 200 μm or less.

[0034] 3 and 4 , the plating layer 34 is omitted, and a first base electrode layer 32a is shown as a representative example, extending from the first end face 12e to a portion of the first main surface 12a. Note that FIGS. 3 and 4 are cross-sectional views perpendicular to the first end face 12e and the second end face 12f. The first base electrode layer 32a is also shown in a similar manner to FIGS. 3 and 4 , extending from the first end face 12e to the second main surface 12b, the first side face 12c, and the second side face 12d. The second base electrode layer 32b is also shown in a similar manner to FIGS. 3 and 4 , extending from the second end face 12f to the first main surface 12a, the second main surface 12b, the first side face 12c, and the second side face 12d.

[0035] As shown in FIGS. 3 and 4 , the base electrode layer 32 includes a sintered glass 60 and a plurality of sintered conductive particles. The glass 60 includes a plurality of glass domains 61. The sintered glass domains 61 of the base electrode layer 32 include an oxide containing at least one element selected from, for example, B, Si, Ba, Mg, Al, Li, Zn, Ca, Bi, Ti, Sr, Ga, etc. The conductive particles of the base electrode layer 32 include sintered metal particles. The metal component of the metal particles includes at least one selected from, for example, Cu, Cu alloy, Ni, Ag, Pd, Ag—Pd alloy, Au, etc. Hereinafter, the conductive particles will be referred to as metal particles. The base electrode layer 32 may also include multiple layers.

[0036] The base electrode layer 32 also has an end surface electrode portion 40 and a wraparound electrode portion 41 .

[0037] The end surface electrode 40 is an electrode that extends over the first end surface 12 e and the second end surface 12 f and over a surface extending along the first end surface 12 e and the second end surface 12 f. The end surface electrode 40 is formed in a state in which a plurality of sintered metal particles and a plurality of sintered glass domains 61 are mixed together. As shown in FIGS. 3 and 4 , some of the plurality of glass domains 61 are located on the first end surface 12 e (and the second end surface 12 f) in the end surface electrode 40. The end surface electrode 40 is bonded to the laminate 12 at a portion that contacts a laminate interface 51 (described below) of the laminate 12. Specifically, the end surface electrode 40 and the laminate 12 are bonded via each of the plurality of glass domains 61 (each of which is a continuous glass domain 61) or a plurality of metal particles present on the first end surface 12 e (and the second end surface 12 f). Furthermore, when focusing on one contact portion where the end electrode 40 and the laminate 12 are in contact via one glass domain 61, it is considered that the end electrode 40 and the laminate 12 are bonded over most or all of that contact portion. Each glass domain 61 is embedded in minute irregularities on the laminate interface 51, which is the surface of the laminate 12, and it is considered that the end electrode 40 and the laminate 12 are bonded together by an anchor effect or the like. Other portions of the multiple glass domains 61 are located in a dispersed state inside the end electrode 40. Alternatively, the multiple glass domains 61 may face the outer surface of the end electrode 40, or may partially protrude from the outer surface.

[0038] The wraparound electrode portion 41 is continuous with the end surface electrode portion 40 and is formed on the laminate 12 by extending from the first end surface 12e and the second end surface 12f to the first principal surface 12a, the second principal surface 12b, the first side surface 12c, and the second side surface 12d. In this embodiment, the wraparound electrode portion 41 is formed on a portion of the first principal surface 12a, a portion of the second principal surface 12b, a portion of the first side surface 12c, and a portion of the second side surface 12d. The wraparound electrode portion 41 may also be formed on at least one of a portion of the first principal surface 12a, a portion of the second principal surface 12b, a portion of the first side surface 12c, and a portion of the second side surface 12d. In the examples of FIGS. 3 and 4 , the wraparound electrode portion 41 is adjacent to the end surface electrode portion 40 via a surface extending along the first end surface 12e (and the second end surface 12f). The plane extending along the first end surface 12e (and the second end surface 12f) has a base end position P A The base end position P Ais the position of the laminate interface 51 closest to the first end face 12e and the second end face 12f. Similarly to the end face electrode 40, the wraparound electrode 41 is formed of a mixture of a plurality of sintered metal particles and a plurality of sintered glass domains 61. As shown in FIGS. 3 and 4 , some of the glass domains 61 are located on the first main surface 12a (the second main surface 12b, the first side surface 12c, and the second side surface 12d) in the wraparound electrode 41. The wraparound electrode 41 and the laminate 12 are bonded together mainly via each of the plurality of glass domains 61 (each of which is a continuous glass domain 61) located on the first main surface 12a (the second main surface 12b, the first side surface 12c, and the second side surface 12d). Alternatively, the wraparound electrode 41 and the laminate 12 may be bonded together via a plurality of metal particles or the like. Further, another portion of the plurality of glass domains 61 is located in a dispersed state inside the wraparound electrode portion 41. Alternatively, the plurality of glass domains 61 may face the outer surface of the wraparound electrode portion 41, or may partially protrude from the outer surface. In the entire base electrode layer 32, including the wraparound electrode portion 41, the content of the glass domains 61 (glass 60) relative to the total content of the glass domains 61 (glass 60), metal particles, various additives, etc. is preferably 5 wt % or more and 20 wt % or less.

[0039] The wraparound electrode portion 41 has a base end side portion 42 and a tip end side portion 43. The base end side portion 42 is a portion of the wraparound electrode portion 41 located on the first end face 12 e and second end face 12 f side (base end side). The tip end side portion 43 is a portion of the wraparound electrode portion 41 that is continuous with the base end side portion 42. The tip end side portion 43 is located on the tip side, away from the first end face 12 e and second end face 12 f, relative to the base end side portion 42.

[0040] Here, the interface of the laminate 12 facing the wraparound electrode portion 41 is referred to as the laminate interface 51. The laminate interface 51 is the outer surface of the laminate 12 and is a surface along the longitudinal direction z. The laminate interface 51 has small irregularities. Furthermore, the interface of the laminate 12 facing the tip side portion 43 among the laminate interfaces 51 is referred to as the tip side interface 53. At the tip side interface 53, the laminate 12 is partially bonded to the tip side portion 43. Specifically, the tip side interface 53 includes at least one tip side bonded interface 53a where the laminate 12 is bonded to the tip side portion 43, and at least one tip side non-bonded interface 53b where the laminate 12 is not bonded to the tip side portion 43. At the tip side non-bonded interface 53b, the laminate 12 is separated from the tip side portion 43. Preferably, at the tip side non-bonded interface 53b, the laminate 12 is separated from the tip side portion 43 while being close to it. Of the laminate interface 51, the interface of the laminate 12 facing the base end portion 42 is referred to as a base end interface 52. At the base end interface 52, the laminate 12 is bonded to substantially the entire base end portion 42.

[0041] The distal end portion 43 and the proximal end portion 42 will be further described below.

[0042] The tip side portion 43 is located on the tip side of the wraparound electrode portion 41. The tip side is the side away from the base end side, which is the side of the first end face 12 e and the second end face 12 f, at the laminate interface 51. In this embodiment, as shown in FIGS. 3 and 4 , in a cross section perpendicular to the first and second end faces 12 e and 12 f, the tip side portion 43 is located at a tip position P B and the end position P D The distal end portion 43 is disposed between the base end position P A and tip position P B The center position P between C In other words, the end position P D is the center position P C The tip position P B is the position on the stack interface 51 that is farthest from the first end face 12e and the second end face 12f. C is the base end position P A and tip position PB and is located at the center of the center position P C and the base end position P A and the center position P C and tip position P B The distance between is roughly the same.

[0043] The tip-side interface 53 is a part of the laminate interface 51 that faces the tip side portion 43 of the wraparound electrode portion 41. The tip-side interface 53 includes at least one tip-side adhesive interface 53a and at least one tip-side non-adhesive interface 53b. For example, the tip-side interface 53 may include one tip-side adhesive interface 53a and one tip-side non-adhesive interface 53b. Furthermore, the tip-side interface 53 may include a mixture of multiple tip-side adhesive interfaces 53a and multiple tip-side non-adhesive interfaces 53b. The laminate 12 is adhered to the tip side portion 43 at each tip-side adhesive interface 53a. Furthermore, the laminate 12 is not adhered to the tip side portion 43 at each tip-side non-adhesive interface 53b. Furthermore, it is preferable that the laminate 12 is spaced apart from the tip side portion 43 while still being close to it at each tip-side non-adhesive interface 53b. The tip-side non-bonded interface 53b is the portion of the tip-side interface 53 excluding the tip-side bonded interface 53a.

[0044] In this embodiment, as shown in FIG. 3, the leading end interface 53 is located at the end position P D From tip position P B At the front end interface 53, the end position P D From position P E The non-adhesive interface 53b on the tip side up to the position P E From position P G The tip-side adhesive interface 53a up to the position P G From position P H The non-adhesive interface 53b on the tip side up to the position P H From tip position P B and a tip-side adhesive interface 53a extending from the tip-side interface 53 to the laminate 12. Here, it is preferable that the tip-side adhesive interface 53a is located at the tip-most side of the tip-side interface 53. In other words, it is preferable that the tip-side portion 43 is bonded to the laminate 12 at the tip-most side. This makes it possible to prevent the tip-side portion 43 from being significantly chipped.

[0045] At each tip-side adhesive interface 53a, the tip side portion 43 and the laminate 12 are bonded together. Specifically, at each tip-side adhesive interface 53a, the tip side portion 43 and the laminate 12 are bonded together via a plurality of glass domains 61 (each continuous glass domain 61) or a plurality of metal particles present on the tip-side interface 53. Furthermore, when focusing on one contact portion where the tip side portion 43 and the laminate 12 are in contact with each other via one glass domain 61, it is considered that the tip side portion 43 and the laminate 12 are bonded together over most or all of that contact portion. Furthermore, it is considered that each glass domain 61 is embedded in minute irregularities in the tip-side interface 53, and that this anchor effect or the like causes the tip side portion 43 and the laminate 12 to be bonded together at the tip-side adhesive interface 53a.

[0046] Each glass domain 61 is detected, for example, by polishing the multilayer ceramic capacitor 10 to expose its cross section, and then performing a composition analysis using EDX (energy dispersive X-ray analysis). The portion where each glass domain 61 exists can be identified by detecting glass components such as Ba, Si, and Al. The abrasive used in the polishing process may contain substances similar to glass components such as Si and Al. Because the abrasive is spherical, it is preferable not to detect spherical glass components as glass domains 61.

[0047] In this embodiment, in FIG. E From position P F Distance L5 and position P F From position P G The total distance L3a from the position P E From position P G The portion of the adhesive interface 53a on the tip side is the portion of the adhesive interface 53a (the portion of the adhesive interface 53a on the tip side). H From tip position P B The portion of the distance L3b from the position P to the position P is another one of the distal end side adhesive interfaces 53a. E From position P FAt the tip-side adhesive interface 53a in the portion of the tip-side portion 43 at a distance L5 from the position P F From position P G At the tip-side adhesive interface 53a in the portion of the tip-side portion 43 over a distance L3a from the position P H From tip position P B At the tip-side adhesive interface 53 a in the portion of the distance L3 b to the tip side portion 43 , the laminate 12 is adhered to the tip side portion 43 via the glass domain 61 .

[0048] 3, in the cross section perpendicular to the first and second end faces 12e, 12f, the distance of at least one tip-side adhesive interface 53a in the tip side portion 43 is preferably 10% to 50% of the distance L2 of the tip-side interface 53. In the example of FIG. 3 of this embodiment, the distance of at least one tip-side adhesive interface 53a is E From position P G Distance L5+distance L3a to position P H From tip position P B The distance L5 to the end position P is the total distance (distance L5 + distance L3a + distance L3b). D and tip position P B The distance between them is L2.

[0049] 3, the distance (distance L5+distance L3a+distance L3b) of at least one distal adhesive interface 53a is preferably 2% to 15% of the distance L1 of the laminate interface 51. A and tip position P B The distance L2 of the front-end interface 53 is preferably, for example, 5% to 30% of the distance L1 of the laminate interface 51.

[0050] On the other hand, at each tip-side non-bonded interface 53b, the laminate 12 is not bonded to the tip side portion 43. In this embodiment, a cavity 54 is located in the tip side portion 43, facing each tip-side non-bonded interface 53b. In the cavity 54, glass domains 61 are mainly absent at each tip-side non-bonded interface 53b. In this embodiment, the cavity 54 is a portion absent of glass domains 61 and metal particles, etc. More specifically, in this embodiment, the cavity 54 is formed with a portion of its periphery surrounded by metal particles, etc., and is in a hollow state absent of glass domains 61 and metal particles, etc. The metal particles are Cu particles, etc., that constitute the tip side portion 43. However, as long as the laminate 12 is not bonded to the tip side portion 43, glass domains 61 and metal particles, etc. may be present at the tip-side non-bonded interface 53b and the cavity 54. In other words, as long as the laminate 12 is separated from the tip side portion 43, glass domains 61 and metal particles may be present at the tip side non-bonded interface 53b and the cavity 54. The separation distance SE between the laminate 12 and the tip side portion 43 is preferably, for example, 8% to 35% of the thickness T1 of the wraparound electrode portion 41. The separation distance SE is preferably, for example, 2 μm to 10 μm. The separation distance SE can also be referred to as the thickness of the cavity 54 in the height direction x.

[0051] The cavities 54 are detected, for example, by polishing the multilayer ceramic capacitor 10 to expose its cross section, and then performing a composition analysis using EDX (energy dispersive X-ray analysis). The portions where the cavities 54 exist can be identified, for example, by detecting elements other than glass components and metal particles such as Cu particles. Elements other than glass components and metal particles such as Cu particles include, for example, carbon (C) and oxygen (O). As mentioned above, it is preferable to exclude spherical glass components contained in the abrasive used in the polishing process when identifying the cavities 54. For example, it is preferable to remove the abrasive remaining in the cavities 54 after the polishing process by ultrasonic cleaning or the like.

[0052] In this embodiment, the end position P D From position P EThe portion of the distance L4a from the position P to the position P is one of the distal end side non-bonded interfaces 53b. G From position P H The portion of the tip end side non-bonded interface 53b is a portion of the tip end side non-bonded interface 53b. D From position P E The non-adhesive interface 53b on the tip side up to the position P G From position P H A series of cavities 54 are present in each of the tip-side non-bonded interfaces 53b from the first to the second. That is, each of the series of cavities 54 constitutes each of the tip-side non-bonded interfaces 53b.

[0053] In a cross-sectional view perpendicular to the first and second end faces 12e and 12f shown in Fig. 3, the distance of at least one tip-side non-bonded interface 53b is preferably 5% to 50% of the distance L2 of the tip-side interface 53. In the example of Fig. 3 of this embodiment, the distance of at least one tip-side non-bonded interface 53b is 5% to 50% of the distance L2 of the end position P D From position P E Distance L4a to position P G From position P H and the distance L4b to the point (distance L4a+distance L4b).

[0054] In addition, in a cross-sectional view perpendicular to the first and second end faces 12e and 12f shown in FIG. 3, the distance (distance L4a+distance L4b) of at least one tip-side non-bonded interface 53b is preferably, for example, 1.5% to 15% of the distance L1 of the laminate interface 51.

[0055] Next, the base end side portion 42 is located on the base end side of the wraparound electrode portion 41. The base end side is the side of the first end face 12e and the second end face 12f at the laminate interface 51. In this embodiment, as shown in FIGS. 3 and 4, in a cross section perpendicular to the first and second end faces 12e and 12f, the base end side portion 42 is located at the terminal position P D and the base end position P A The end position P D is the starting point of the proximal side portion 42 and the ending point of the distal side portion 43. A is the end point of the proximal side portion 42.

[0056] The base-end side interface 52 is a part of the laminate interface 51 that faces the base-end side portion 42 of the wraparound electrode portion 41. The base-end side interface 52 is a part of the laminate interface 51 excluding the tip-end side interface 53. The base-end side interface 52 includes at least one base-end side adhesive interface 52a. In this embodiment, as shown in FIGS. 3 and 4 , the base-end side interface 52 is located at a base position P A to the end position P D The laminate 12 is bonded to the proximal side portion 42 at at least one proximal adhesive interface 52a. At each proximal adhesive interface 52a, the proximal side portion 42 and the laminate 12 are bonded. Specifically, at each proximal adhesive interface 52a, the proximal side portion 42 and the laminate 12 are bonded via a plurality of glass domains 61 (each continuous glass domain 61) or a plurality of metal particles present on the proximal interface 52. Furthermore, when focusing on one contact portion where the proximal side portion 42 and the laminate 12 are in contact with each other via one glass domain 61, it is considered that the proximal side portion 42 and the laminate 12 are bonded over most or all of that contact portion. Furthermore, it is considered that each glass domain 61 is embedded in minute irregularities in the proximal interface 52, and that the proximal side portion 42 and the laminate 12 are bonded at the proximal adhesive interface 52a due to an anchor effect or the like. The method for detecting each glass domain 61 is as described above. In this embodiment, each base-end adhesive interface 52a is continuous to form a series of base-end adhesive interfaces 52a.

[0057] Position P I From position P J The distance L7a to the position P K From position P L The distance L7b to the position P M From position P N The distance L7c to the position P O From position P p The distance L7d to the position P Q From position P R At each base-side adhesive interface 52a in the portion of the base-side position P AFrom position P I The distance L8a to the position P J From position P k The distance L8b to the position P L From position P M The distance L8c to the position P N From position P O The distance L8d to the position P P From position P Q The distance L8e to the position P R to the end position P D At each base-side adhesive interface 52a in the portion of the base end position P A to the end position P D A series of base-end side adhesive interfaces 52a are formed, and the laminate 12 is bonded to the base-end side portion 42 at the series of base-end side adhesive interfaces 52a via the glass domains 61, metal particles, etc.

[0058] As described above, in the present embodiment, substantially the entire base-side interface 52 is made up of a series of base-side adhesive interfaces 52a, and the laminate 12 is adhered to the base-side portion 42 over substantially the entire base-side interface 52. Alternatively, the laminate 12 may not be adhered to the base-side portion 42 over a portion of the base-side interface 52. For example, the base-side interface 52 may include a plurality of discontinuous base-side adhesive interfaces 52a.

[0059] The content of glass 60 present at the distal interface 53 is lower than the content of glass 60 present at the proximal interface 52. In other words, the continuity of glass 60 at the distal interface 53 is lower than the continuity of glass 60 at the proximal interface 52. The content of glass 60 can be determined, for example, using an EDX (energy dispersive X-ray) analyzer. A specific description will be given with reference to FIG. 5 . In FIG. 5 , (a) shows the results of Al detection using the EDX analyzer from the distal portion to a portion of the proximal portion, and (b) shows the results of Cu detection using the EDX analyzer at the same location as (a). Using the EDX analyzer, a line analysis was performed at the laminate interface 51 from the distal portion 43 to a portion of the proximal portion 42. As shown in FIG. 5 (a), the distal portion 43 has a cavity 54, and the Al content at the distal interface 53 is lower than the Al content at the proximal interface 52. Al is one of the glass components of glass 60. Therefore, it can be seen that the content of glass 60 at the distal interface 53 is lower than the content of glass 60 at the proximal interface 52. In particular, it can be seen that the content of glass 60 is lower in the portion of the distal interface 53 where the cavity 54 is present. This shows that the range of the adhesive region between the distal portion 43 and the laminate 12 via the glass 60 (included in the distal adhesive interface 53a) is smaller than the range of the adhesive region between the proximal portion 42 and the laminate 12 via the glass 60 (included in the proximal adhesive interface 52a). Note that, as shown in FIGS. 5A and 5B , not only the content of glass 60 but also the content of Cu is lower in the cavity 54 at the distal interface 53. On the other hand, the cavity 54 is almost absent at the proximal interface 52. From the above, it can be seen that the range of the adhesive region (included in the distal adhesive interface 53a) between the distal side portion 43 and the laminate 12 via the glass 60 or metal particles is smaller than the range of the adhesive region (included in the proximal adhesive interface 52a) between the proximal side portion 42 and the laminate 12 via the glass 60 or metal particles. Therefore, it can be seen that the distal side portion 43 is partially adhered to the laminate 12 and partially not adhered thereto.

[0060] The continuity of the glass 60 at the distal interface 53 is represented, for example, by the distance of the glass 60 present at the distal interface 53 relative to the distance L2 at the distal interface 53. In the example of FIG. 3 , the distance of the glass 60 at the distal interface 53 is distance L3a+distance L3b. Similarly, the continuity of the glass 60 at the proximal interface 52 is represented, for example, by the distance of the glass 60 present at the proximal interface 52 relative to the distance at the proximal interface 52. The distance at the proximal interface 52 is distance L6, as described below. In the example of FIG. 3 , the distance of the glass 60 at the proximal interface 52 is distance L7a+distance L7b+distance L7c+distance L7d+distance L7e.

[0061] In addition, the central position P C From tip position P B The adhesive area between the wraparound electrode portion 41 and the laminate 12 is at the base end position P A From the center position P C The area is smaller than the adhesive area between the wraparound electrode portion 41 and the laminate 12 .

[0062] 3 , the ratio of the distance of at least one distal adhesive interface 53a (distance L5+distance L3a+distance L3b) to the distance L2 of the distal interface 53 is defined as the distance of the distal adhesive interface 53a / the distance of the distal interface 53. The ratio of the distance of at least one proximal adhesive interface 52a to the distance of the proximal interface 52 is defined as the distance 52a of the proximal adhesive interface 52. It can be said that the distance of the distal adhesive interface 53a / the distance of the distal interface 53 is smaller than the distance 52a of the proximal adhesive interface / the distance 52 of the proximal interface 52. In this embodiment, the distance of at least one base-side adhesive interface 52a is the total distance of distance L7a + distance L7b + distance L7c + distance L7d + distance L7e + distance L8a + distance L8b + distance L8c + distance L8d + distance L8e + distance L8f (distances L7a to L7e + distances L8a to L8f). The distance of the base-side interface 52 is distance L6. The ratio of the distance 52a of the base-side adhesive interface to the distance of the base-side interface 52 is, for example, 40% or more and 80% or less. As described above, the ratio of the distance of the tip-side adhesive interface 53a to the distance of the tip-side interface 53 is, for example, 10% or more and 50% or less.

[0063] 3, the ratio of the distance of at least one distal adhesive interface 53a (distance L5 + distance L3a + distance L3b) to the distance L1 of the laminate interface 51 is defined as the distance of the distal adhesive interface 53a / the distance of the laminate interface 51. The ratio of the distance of at least one proximal adhesive interface 52a (distances L7a to L7e + distances L8a to L8f) to the distance L1 of the laminate interface 51 is defined as the distance of the proximal adhesive interface 52a / the distance of the laminate interface 51. The distance of the distal adhesive interface 53a / the distance of the laminate interface 51 can be said to be smaller than the distance of the proximal adhesive interface 52a / the distance of the laminate interface 51. The distance of the proximal adhesive interface 52a / the distance of the laminate interface 51 is, for example, 35% or more and 75% or less. As described above, the distance of the tip-side adhesive interface 53a / the distance of the laminate interface 51 is, for example, 2% or more and 15% or less.

[0064] In addition, in a cross-sectional view perpendicular to the first and second end faces 12e, 12f shown in FIG. 3, the total distance along the laminate interface 51 of at least one tip-side adhesive interface 53a and at least one base-side adhesive interface 52a (distance L5+distance L3a+distance L3b+distances L7a to L7e+distances L8a to L8f) is preferably, for example, 40% or more and 70% or less of the distance L1 of the laminate interface 51.

[0065] In a cross-sectional view perpendicular to the first and second end faces 12 e and 12 f shown in FIGS. 3 and 4 , the glass 60 includes a plurality of glass domains 61 as described above. The distance over which each glass domain 61 contacts along the laminate interface 51 is preferably, for example, 0.1% to 10% of the distance L1 of the laminate interface 51. The distances over which each glass domain 61 contacts along the laminate interface 51 at the base end side portion 42 are distances L7a, L7b, L7c, L7d, and L7e, respectively, as shown in FIG. 4 . The distances over which each glass domain 61 contacts along the laminate interface 51 at the tip end side portion 43 are distances L3a and L3b, respectively, as shown in FIG. 3 .

[0066] 3 and 4 , thickness T2 of each glass domain 61 in contact with stack interface 51 in a direction perpendicular to stack interface 51 is preferably, for example, 0.1% to 20% of thickness T1 of wraparound electrode portion 41 in a direction perpendicular to stack interface 51. Thickness T2 of each glass domain 61 is, for example, 0.2 μm to 5.0 μm.

[0067] The plating layer 34 includes a first plating layer 34a and a second plating layer 34b. The first plating layer 34a is disposed so as to cover the first base electrode layer 32a. The second plating layer 34b is disposed so as to cover the second base electrode layer 32b. The first plating layer 34a and the second plating layer 34b each include at least one selected from the group consisting of Cu, Ni, Sn, Ag, Pd, an Ag—Pd alloy, and Au.

[0068] The first plating layer 34 a and the second plating layer 34 b may be formed of multiple layers. In this case, the plating layer 34 preferably has a two-layer structure including a lower plating layer formed by Ni plating on the base electrode layer 32 and an upper plating layer formed by Sn plating on the lower plating layer.

[0069] That is, the first plating layer 34a has a first lower plating layer and a first upper plating layer located on the surface of the first lower plating layer, and the second plating layer 34b has a second lower plating layer and a second upper plating layer located on the surface of the second lower plating layer.

[0070] The Ni-plated lower layer is used to prevent the base electrode layer 32 from being eroded by solder when the multilayer ceramic capacitor 10 is mounted on a substrate or the like. The Sn-plated upper layer is used to improve the wettability of solder when the multilayer ceramic capacitor 10 is mounted on a substrate or the like, thereby facilitating mounting. The thickness of each of the upper and lower plating layers is preferably, for example, 2.0 μm or more and 15.0 μm or less.

[0071] The dimensions of the multilayer ceramic capacitor 10 are not particularly limited, but the L dimension in the length direction z is, for example, 0.25 mm to 10.5 mm, the W dimension in the width direction y is, for example, 0.12 mm to 10.5 mm, and the T dimension in the height direction x is, for example, 0.12 mm to 5.5 mm. Note that the L dimension in the length direction z is not necessarily longer than the W dimension in the width direction y and the T dimension in the height direction x.

[0072] 2. Method for Manufacturing the Multilayer Ceramic Capacitor Next, a method for manufacturing the multilayer ceramic capacitor 10 will be described.

[0073] (Step 1) First, a dielectric sheet for the ceramic layer and a conductive paste for the internal electrode layer are prepared. The dielectric sheet for the ceramic layer is formed from a dielectric slurry containing, for example, but not limited to, BaTiO3 as a main component. The conductive paste for the internal electrode layer is formed from, for example, but not limited to, Ni as a main component. The dielectric sheet and the conductive paste for the internal electrode layer contain a binder and a solvent. The binder and solvent are composed of a resin component, and various known thermosetting resins such as epoxy resin, phenoxy resin, phenolic resin, urethane resin, and polyimide resin can be used as the resin component.

[0074] (Step 2) Then, a conductive paste for the internal electrode layers is printed in a predetermined pattern on the dielectric sheet by, for example, screen printing, gravure printing, etc. In this way, a dielectric sheet on which the pattern of the first internal electrode layer is formed, and a dielectric sheet on which the pattern of the second internal electrode layer is formed are prepared.

[0075] Furthermore, with regard to the dielectric sheets, dielectric sheets for outer layer portions on which no patterns of internal electrode layers are printed are also prepared.

[0076] A predetermined number of dielectric sheets for the outer layer portion, on which the pattern of the internal electrode layer is not printed, are laminated. 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 laminated in this order on top of the dielectric sheets, to form a portion that will become the effective layer portion. A predetermined number of dielectric sheets for the outer layer portion, on which the pattern of the internal electrode layer is not printed, are laminated on top of this portion that will become the effective layer portion. In this way, a laminate sheet having an effective layer portion and an outer layer portion is formed.

[0077] (Step 3) Next, the laminated sheet is pressed in the lamination direction by means of a hydrostatic press or the like to produce a laminated block.

[0078] (Step 4) The laminated block is then cut to a predetermined size to cut out laminated chips.

[0079] (Step 5) Next, the resin component in the stacked chip is removed. The degreasing temperature for removing the resin component in step 5 is, for example, higher than 600°C and not higher than 1000°C.

[0080] (Step 6) Next, the laminated chip is fired to produce the laminate 12. The firing temperature for the laminated chip depends on the materials of the ceramic layers and internal electrode layers, which are dielectrics, but is preferably higher than 950°C and lower than 1400°C, for example. This firing fires the patterns of the internal electrode layers and the dielectric sheets, turning them into the internal electrode layers 16 and ceramic layers 14.

[0081] (Step 7) Next, the base electrode layer paste 71 is applied to the first and second end faces 12e, 12f of the laminate 12 and fired, thereby forming the base electrode layer 32 of the external electrode 30.

[0082] Step 7 will be described in more detail. In Fig. 6, (a) is a schematic diagram showing an embodiment of the base electrode layer paste according to the present embodiment, and (b) is a schematic diagram showing an embodiment of the base electrode layer paste different from that of the present embodiment. Fig. 7 is a schematic diagram showing a state in which the base electrode layer paste according to the present embodiment is being applied to a laminate.

[0083] (a) Preparation of Base Electrode Layer Paste First, a base electrode layer paste 71 according to this embodiment, shown in FIG. 6A, will be described. The base electrode layer paste 71 is a paste for forming the base electrode layer 32. The base electrode layer paste 71 according to this embodiment contains a resin, a plurality of conductive metal powders (metal powders 72), a plurality of glass powders 73, and a solvent. The metal component of the metal powder contains at least one selected from, for example, Cu, a Cu alloy, Ni, Ag, Pd, an Ag—Pd alloy, and Au.

[0084] As the resin, various known thermosetting resins such as acrylic resin, ethyl cellulose resin, epoxy resin, phenoxy resin, phenol resin, urethane resin, and polyimide resin can be used.

[0085] The major axis of each metal powder 72 is designated a1 and the minor axis is designated b1. The aspect ratio (b1 / a1) of the metal powder 72 is preferably, for example, 50:1 to 2:1, that is, for example, 2 or more and 50 or less. Furthermore, almost all of the multiple metal powders 72 in the base electrode layer paste 71 are adjusted to the above-mentioned aspect ratio (b1 / a1). In other words, it is preferable that the particle sizes of the multiple metal powders 72 are approximately uniform. The major axis a1 is preferably, for example, 1 μm or more and 10 μm or less, and the minor axis b1 is preferably, for example, 0.1 μm or more and 1 μm or less.

[0086] The content of the metal powder 72 in the base electrode layer paste 71 is preferably, for example, 15% by volume or more and 35% by volume or less.

[0087] The glass powder 73 contains at least one element selected from, for example, B, Si, Ba, Mg, Al, Li, Zn, Ca, Bi, Ti, Sr, Ga, etc. The sphere-equivalent diameter dg of the glass powder 73 is preferably, for example, 0.5 μm or more and 3.0 μm or less. In the base electrode layer paste 71, the ratio of the content of the glass powder 73 to the content of the metal powder 72 and the glass powder 73 (content of glass powder 73 / (content of metal powder 72+content of glass powder 73)) is preferably, for example, 10% by volume or more and 30% by volume or less. Furthermore, the glass softening point of the glass powder 73 is preferably, for example, 500° C. or more and 700° C. or less.

[0088] The solvent may include, for example, at least one of terpineol, dihydroterpineol, dihydroterpinyl acetate, propylene glycol phenyl ether, benzyl alcohol, texanol, and butyl carbitol acetate. The solvent species can be analyzed by measuring the evolved gas using gas chromatography-mass spectrometry. Gas chromatography-mass spectrometry can be performed using, for example, a mass spectrometer 7890A / 5975C (heated to 500°C) manufactured by Agilent Technologies, Inc.

[0089] In addition, the base electrode layer paste 71 may contain various additives such as a dispersant, a plasticizer, an anti-settling agent, and a thixotropic agent.

[0090] The paste 71 for the base electrode layer is produced by weighing and mixing resin, metal powder 72, glass powder 73, and a solvent to a predetermined mixing ratio, and dispersing and kneading the mixture using a three-roll mill or the like.

[0091] Note that (b) in FIG. 6 illustrates a base electrode layer paste 71a different from the base electrode layer paste 71 of the present embodiment to explain the differences from the base electrode layer paste 71 of the present embodiment. The base electrode layer paste 71a, which differs from the base electrode layer paste 71 of the present embodiment, contains a resin, a conductive metal powder (metal powder 72a), a glass powder 73, and a solvent. The resin, metal powder 72a, glass powder 73, and solvent components of the base electrode layer paste 71a are the same as those of the base electrode layer paste 71. However, the metal powder 72a is a mixture of flat and spherical particles. Furthermore, at least a portion of the flat metal powder 72a has a different aspect ratio, etc., from the flat metal powder 72 of the present embodiment. The base electrode layer paste 71a will be described later.

[0092] (b) Method for Forming Base Electrode Layer Next, a method for forming the base electrode layer 32 using the base electrode layer paste 71 according to the present embodiment will be described. In this embodiment, first, as shown in FIG. 7 , in a base electrode layer paste application step, the base electrode layer paste 71 is applied to the laminate 12. Then, in a base electrode layer paste drying step, the base electrode layer paste 71 applied to the laminate 12 is dried to form a dry film. Then, in a dried film degreasing step, the resin component in the dry film is degreased to form a base electrode layer before sintering. Then, a firing step for metal sintering is performed. The base electrode layer paste application step, the base electrode layer paste drying step, the dried film degreasing step, and the firing step for metal sintering will be described below.

[0093] (b1) Step of Applying Base Electrode Layer Paste In the step of applying the base electrode layer paste, the region of the laminate 12 where the base electrode layer 32 is to be formed is immersed in the base electrode layer paste 71 in the paste tank 75, and then the laminate 12 is pulled up. In this embodiment, the laminate 12 is immersed so that the end faces (first end face 12 e, second end face 12 f) of the laminate 12 face the base electrode layer paste 71. In this embodiment, the region where the base electrode layer 32 is to be formed refers to the first end face 12 e, the second end face 12 f, part of the first main surface 12 a, part of the second main surface 12 b, part of the first side surface 12 c, and part of the second side surface 12 d of the laminate 12.

[0094] When the laminate 12 is pulled up, Marangoni convection occurs between the center and the ends of the base electrode layer paste 71 attached to the laminate 12 due to differences in temperature and solute concentration between the center and the ends. The center is the portion of the base electrode layer paste 71 that is applied mainly to the central portions of the end faces (first end face 12 e, second end face 12 f) of the laminate 12. The ends are the portions of the base electrode layer paste 71 that are applied mainly to a portion of the first principal surface 12 a, a portion of the second principal surface 12 b, a portion of the first side surface 12 c, and a portion of the second side surface 12 d of the laminate 12. Due to the Marangoni convection that occurs between the center and the ends in the base electrode layer paste 71 and the fact that the base electrode layer paste 71 is pulled in the direction of gravity, the thickness of the base electrode layer paste 71 becomes relatively large in the center. On the other hand, the thickness of the base electrode layer paste 71 is relatively smaller at the ends than at the center. The base electrode layer paste 71 dries more easily at the thinner ends than at the thicker center. The solutes are the metal powder 72, the glass powder 73, and the resin contained in the base electrode layer paste 71.

[0095] Furthermore, even at the end, the base electrode layer paste 71 is pulled in the direction of gravity, so that the thickness of the base electrode layer paste 71 gradually changes from a thin state to a thick state from the tip portion on the tip side to the portion continuing to the center portion. The thin portion (tip portion) is more likely to dry than the thick portion (portion continuing to the center portion). The tip portion is the portion that becomes the tip side portion 43 and corresponds to the tip-side interface 53. The portion continuing to the center portion is the portion that becomes the base side portion 42 and corresponds to the base-side interface 52.

[0096] As described above, the aspect ratio (b1 / a1) of the metal powder 72 in the base electrode layer paste 71 is, for example, 50:1 to 2:1, i.e., 2 or more and 50 or less. Such metal powder 72 has a flat, elongated shape. First, at the ends, the metal powder 72 is pulled in the direction of gravity, and thus tends to be aligned so that its major axis direction is aligned along the application surfaces of the first and second principal surfaces 12a, 12b and the first and second side surfaces 12c, 12d. That is, as shown in FIG. 6A, the metal powder 72 tends to be aligned so that its major axis direction is aligned along the laminate interface 51. In particular, as described above, at the ends, the tip portion (the portion that becomes the tip side portion 43 and corresponds to the tip-side interface 53) is thinner in thickness and more likely to be dry than the portion continuous with the center portion (the portion that becomes the base side portion 42 and corresponds to the base-side interface 52), and therefore the fluidity of the glass powder 73 tends to be suppressed. Therefore, in the distal portion, the metal powder 72, whose major diameter direction is aligned along the application surface, reduces the paths through which the glass powder 73 flows to the distal interface 53, and the more advanced dry state suppresses the flow of the glass powder 73 to the distal interface 53. Therefore, the content of the glass powder 73 at the distal interface 53 is relatively smaller than that at the base interface 52. In other words, the glass powder 73 is present only partially at the distal interface 53.

[0097] Furthermore, by adjusting the glass softening point of the glass powder 73 to, for example, 500°C or higher and 700°C or lower, and adjusting the content of the glass powder 73 in the base electrode layer paste 71, the fluidity of the glass powder 73 at the tip portion is suppressed in combination with the aspect ratio of the metal powder 72. Therefore, the glass powder 73 is only partially present at the tip-side interface 53. The content of the glass powder is, for example, 3% by volume or higher and 15% by volume or lower.

[0098] In addition, it is believed that by relatively slowing down the speed at which the laminate 12 immersed in the base electrode layer paste 71 is pulled up, the metal powder 72 can be more easily arranged at the tip portion so that the long diameter direction is along the tip side interface 53.

[0099] On the other hand, in the portion continuous with the central portion (the portion that becomes the base-end side portion 42 and corresponds to the base-end interface 52), the drying process progresses more slowly than in the tip portion (the portion that becomes the tip-end side portion 43 and corresponds to the tip-end interface 53), and therefore the metal powder 72 tends to be randomly oriented, with its major axis direction not aligned with the coating surface. Therefore, the glass powder 73 in the base electrode layer paste 71 flows through more paths to the base-end interface 52 than to the tip-end interface 53. Therefore, the content of glass powder 73 at the base-end interface 52 tends to be higher than at the tip-end interface 53. In other words, the glass powder 73 is present in a relatively continuous manner at the base-end interface 52.

[0100] Furthermore, at the first and second end faces 12a, 12b, including the central portion, gravity tends to make it difficult for the metal powder 72 to be arranged diametrically along the first and second end faces 12a, 12b. Furthermore, the thickness of the base electrode layer paste 71 is relatively large in the central portion, and the drying process proceeds more slowly. Therefore, the metal powder 72 tends to be oriented in a random manner similar to or even more randomly than the portion continuous with the central portion. Therefore, at the first and second end faces 12e, 12f, the glass powder 73 is present at the same level as or more continuously than the base-end interface 52.

[0101] (b2) Step of drying the base electrode layer paste Next, a drying step is performed to volatilize the solvent in the base electrode layer paste 71 applied to the laminate 12. The drying temperature is, for example, 90°C or higher and 200°C or lower, for example, 140°C. This causes the base electrode layer paste 71 to dry. The film formed by drying the base electrode layer paste 71 is called a dried film. The drying step is preferably performed in a reducing atmosphere.

[0102] (b3) Degreasing step of dried film Next, the degreasing step of the dried film is carried out. That is, the resin component in the dried film is degreased. As a result, the dried film becomes an unsintered base electrode layer. The degreasing temperature is, for example, 120°C or higher and 600°C or lower, for example, 350°C.

[0103] (b4) Firing step for metal sintering Next, after a degreasing step for the dried film, the laminate 12 coated with the green base electrode layer is fired in a predetermined firing atmosphere. This forms the sintered base electrode layer 32 shown in Figures 3 and 4. That is, the metal powder 72 and the glass powder 73 in the base electrode layer paste 71 are sintered to become metal particles and glass 60, respectively.

[0104] As described above, after the steps of applying the base electrode layer paste, drying the base electrode layer paste, and degreasing the dried film, the glass powder 73 is only partially present at the tip-side interface 53. Therefore, the laminate 12 is partially bonded to the tip side portion 43 at the tip-side interface 53. Specifically, in the portion of the tip-side interface 53 where the glass powder 73 is present, most or all of the laminate 12 in that portion is bonded to the tip side portion 43 via the glass 60 upon firing. At this time, it is believed that the glass powder 73 melts upon firing and penetrates into the minute irregularities of the tip-side interface 53, thereby further bonding the tip side portion 43 and the laminate 12 via the glass 60 due to an anchor effect or the like. Furthermore, in the present embodiment, in the portion of the tip-side interface 53 where the metal powder 72 is present, the laminate 12 is further bonded to the tip side portion 43 via metal particles or the like upon firing. This bonded portion becomes the tip-side adhesive interface 53a. On the other hand, in a portion of the tip-side interface 53 where the glass powder 73 is not present, the laminate 12 is not bonded to the tip side portion 43. This non-bonded portion becomes the tip-side non-bonded interface 53b. As a result, the tip-side interface 53 includes at least one tip-side bonded interface 53a and at least one tip-side non-bonded interface 53b.

[0105] Furthermore, as described above, after the steps of applying the base electrode layer paste, drying the base electrode layer paste, and degreasing the dried film, the glass powder 73 is present more continuously at the base-end interface 52 than at the tip-end interface 53. Therefore, at the base-end interface 52, the laminate 12 is relatively continuously bonded to the base-end portion 42 mainly via the glass 60. At this time, it is thought that the glass powder 73 melts during firing and penetrates into the minute irregularities of the base-end interface 52, thereby providing an anchor effect and further bonding the base-end portion 42 and the laminate 12 via the glass 60. Furthermore, in this embodiment, the laminate 12 is further bonded to the base-end portion 42 via metal particles and the like. This bonded portion becomes the base-end bonding interface 52a.

[0106] To suppress the fluidity of the metal powder 72 and the glass powder 73, it is preferable that the amount of resin, solvent, etc. remaining in the unsintered base electrode layer be small during the metal sintering firing process. Therefore, it is preferable that the resin and solvent in the base electrode layer paste 71 have good thermal decomposition properties and are easily degreased during the base electrode layer paste drying process, the dried film degreasing process, and the metal sintering firing process. The firing conditions for the metal sintering firing process are preferably within a temperature range in which the resin, solvent, etc. are thermally decomposed. Furthermore, the firing atmosphere for the metal powder 72 is preferably a reducing atmosphere, and an oxidizing atmosphere is preferable in order to gasify the carbon (C) in the unsintered base electrode layer during firing. The firing temperature during the metal sintering firing process is preferably, for example, between 700°C and 900°C.

[0107] The base electrode layer paste 71a shown in FIG. 6B, which differs from the present embodiment, contains a resin, a conductive metal powder (metal powder 72a), a glass powder 73, and a solvent, as described above. The resin, metal powder 72a, glass powder 73, and solvent components of the base electrode layer paste 71a are the same as those of the base electrode layer paste 71. However, the metal powder 72a is a mixture of flat and spherical particles, with the proportion of spherical particles being higher than the proportion of flat particles. The flat metal powder 72a also includes particles with an aspect ratio different from that of the metal powder 72 according to the present embodiment. The metal powder 72a has a major axis a2 and a minor axis b2. The aspect ratio (b2 / a2) of at least a portion of the metal powder 72a is, for example, less than 2:1, i.e., less than 2.

[0108] The base electrode layer paste 71a is poured into the paste tank 75. The area of ​​the laminate 12 where the base electrode layer 32 is to be formed is immersed in the base electrode layer paste 71a in the paste tank 75, and then the laminate 12 is lifted out. The base electrode layer paste 71a contains a mixture of flat and spherical metal powder particles 72a, including particles with an aspect ratio (b2 / a2) of less than 2. Therefore, even if the metal powder particles 72 are arranged in the distal end portion with their major diameters aligned along the application surfaces (the distal interface 53 and the proximal interface 52) of the first and second principal surfaces 12a, 12b and the first and second side surfaces 12c, 12d, the glass powder particles 73 have a relatively large number of paths along which they flow toward the application surfaces. Therefore, the glass powder particles 73 are present in a relatively continuous manner at the distal interface 53 and the proximal interface 52. The density at which the glass powder 73 shown in Fig. 6(b) is arranged at the laminate interface 51 is relatively higher than the density at which the glass powder 73 shown in Fig. 6(a) is arranged at the laminate interface 51. As a result, after the firing process for metal sintering, the laminate 12 is bonded to the wraparound electrode portion 41 via the glass 60, etc., over substantially the entire distal interface 53 and the proximal interface 52. Similarly, the laminate 12 is bonded to the end surface electrode portion 40 via the glass 60, etc., over substantially the entire interface.

[0109] (Step 8) Next, the plating layer 34 is formed on the base electrode layer 32. The plating layer 34 is formed, for example, by laminating a Ni plating layer and a Sn plating layer in this order on the base electrode layer 32.

[0110] The multilayer ceramic capacitor 10 is manufactured by the above-described manufacturing method. The base electrode layer paste 71 of the multilayer ceramic capacitor 10 has the above-described characteristics. The characteristics of the base electrode layer paste 71 can be described, for example, as follows.

[0111] The base electrode layer paste 71 contains a resin, a conductive metal powder (metal powder 72), a glass powder 73, and a solvent. The aspect ratio (b1 / a1) of the metal powder 72 is preferably 50:1 to 2:1, that is, 2 or more and 50 or less. The glass softening point of the glass powder 73 is preferably 500°C or more and 700°C or less. The content of the glass powder 73 / (content of the metal powder 72 + content of the glass powder 73) is preferably 10% by volume or more and 30% by volume or less.

[0112] 3. Effects The effects of the characteristic portions of the present application are as follows. (1) According to this embodiment, the tip-side interface 53 of the wraparound electrode portion 41 includes at least one tip-side adhesive interface 53a and at least one tip-side non-adhesive interface 53b, as shown in FIG. 3 . That is, the tip-side portion 43 of the wraparound electrode portion 41 is adhered to the laminate 12 at at least one tip-side adhesive interface 53a and is not adhered to the laminate 12 at at least one tip-side non-adhesive interface 53b, and is separated from the laminate 12. In this way, the tip-side portion 43 of the wraparound electrode portion 41 is not adhered to the laminate 12 over the entire tip-side interface 53 of the laminate 12, but is partially adhered to the laminate 12. By configuring the tip side portion 43 of the wraparound electrode portion 41 in this manner, when stress is applied to the multilayer ceramic capacitor 10 and the wraparound electrode portion 41, the tip side portion 43 is somewhat more likely to peel off from the laminate 12 and to bend slightly. This allows the stress to be dispersed, thereby preventing cracks from occurring in the ceramic layers 14 of the laminate 12 and, ultimately, in the internal electrode layers 16. Meanwhile, because the tip side portion 43 is partially bonded to the laminate 12, it is possible to prevent the tip side portion 43 from peeling off significantly, chipping, or the like. This prevents the tip side portion 43 from chipping significantly, which could cause the symmetry of the pair of external electrodes 30 to be lost, resulting in poor alignment during substrate mounting, for example.

[0113] In addition, the stress applied to the tip side portion 43 tends to move toward the base side portion 42 of the wraparound electrode portion 41 rather than toward the laminate 12, for example, as the tip side portion 43 moves in the direction of peeling off from the laminate 12 or in the direction of bending.

[0114] Furthermore, because the tip side portion 43 is partially adhered to the laminate 12 while being partially separated from the laminate 12, the separation distance SE between the tip side portion 43 and the laminate interface 51 can be kept relatively small. Here, the plating material used in wet plating or the like may contain media to ensure electrical conductivity, prevent overlapping of multiple multilayer ceramic capacitors, etc. As described above, by keeping the separation distance SE between the tip side portion 43 and the laminate interface 51 relatively small, it is possible to prevent media from entering the separation portion between the tip side portion 43 and the laminate interface 51 during the plating process. Therefore, it is possible to prevent the tip side portion 43 from being severely damaged, such as being severely peeled off, due to the media colliding with the separation portion during the plating process.

[0115] Examples of stresses in the multilayer ceramic capacitor 10 include thermal stress, tensile stress, compressive stress, shear stress, bending stress, and residual stress. Stresses can occur in the multilayer ceramic capacitor 10, for example, during a solder reflow process when mounting the multilayer ceramic capacitor 10 on a mounting substrate, during transportation and operation of the multilayer ceramic capacitor 10 mounted on the mounting substrate, and during sintering shrinkage of the external electrodes 30. Thermal stress, tensile stress, compressive stress, shear stress, bending stress, and the like can be generated by an external force applied to the multilayer ceramic capacitor 10. Residual stress is stress that exists within the multilayer ceramic capacitor 10 when no external force is applied to the multilayer ceramic capacitor 10.

[0116] As described above, according to the present embodiment, it is possible to provide a multilayer ceramic capacitor capable of relaxing stress.

[0117] Hereinafter, a cross-sectional SEM image of the multilayer ceramic capacitor 10 according to this embodiment manufactured by the above-described manufacturing method and a cross-sectional SEM image of a multilayer ceramic capacitor different from this embodiment will be described. Fig. 8 is an SEM image of a cross section of a portion of the tip end side and base end side of this embodiment before a plating layer is formed. Fig. 9 is an SEM image of a cross section of a portion of the tip end side and base end side different from this embodiment before a plating layer is formed. Figs. 8 and 9 were taken at 500x magnification.

[0118] In the cross-sectional SEM image of the multilayer ceramic capacitor 10 according to this embodiment shown in FIG. 8 , similar to FIGS. 3 and 4 , the wraparound electrode portion 41 of the base electrode layer 32 was formed in a state in which a plurality of sintered glass domains 61 were dispersed among a plurality of sintered conductive particles (metal particles). The wraparound electrode portion 41 had a base end portion 42 and a tip end portion 43. The tip end interface 53 of the laminate 12, which faces the tip end portion 43 of the laminate interface 51, contained a mixture of a plurality of tip end adhesive interfaces 53 a and a plurality of tip end non-adhesive interfaces 53 b. At each tip end adhesive interface 53 a, the laminate 12 was bonded to the tip end portion 43 primarily via each of the plurality of glass domains 61 and via metal particles, etc. At each tip end non-adhesive interface 53 b, a cavity 54 was located, and the laminate 12 was not bonded to the tip end portion 43.

[0119] Therefore, the tip side portion 43 is bonded to the laminate 12 at a plurality of tip side adhesive interfaces 53a, and is not bonded to the laminate 12 at a plurality of tip side non-adhesive interfaces 53b, and is separated from the laminate 12. When stress is applied to the wraparound electrode portion 41, the tip side portion 43 is somewhat more likely to peel off from the laminate 12 and to bend somewhat. This allows the stress to be dispersed, thereby preventing cracks from occurring in the ceramic layers 14 of the laminate 12 and, ultimately, in the internal electrode layers 16. Note that the stress applied to the tip side portion 43 is thought to be directed toward the base side portion 42, not toward the laminate 12, as shown by the arrow in FIG. 8, for example.

[0120] On the other hand, multiple base-end adhesive interfaces 52a were included throughout almost the entire base-end interface 52, and almost the entire base-end side portion 42 was adhered to the laminate 12 mainly via multiple glass domains 61 and also via metal particles, etc.

[0121] Next, in the cross-sectional SEM image of a multilayer ceramic capacitor different from the present embodiment shown in FIG. 9 , the wraparound electrode portion 41 of the base electrode layer 32 was formed in a state in which multiple sintered glass domains 61 were dispersed among the sintered metal particles. The wraparound electrode portion 41 had a base end portion 42 and a tip end portion 431. The laminate 12 was bonded to the wraparound electrode portion 41 via glass 60 or metal particles over substantially the entirety of the tip end interface 531 and the base end interface 52 of the laminate interface 51a. The tip end interface 531 is the interface where the laminate 12 faces the tip end portion 431. Therefore, when stress is applied to the wraparound electrode portion 41, the tip end portion 431 is less likely to peel off from the laminate 12 and is less likely to bend. This makes it difficult for the tip end portion 431 to disperse stress, which makes it more likely for cracks to occur in the ceramic layers 14 of the laminate 12 and, ultimately, in the internal electrode layers 16. It is considered that the stress applied to the tip side portion 431 is directed from the tip side portion 431 toward the inside of the laminate 12, for example, as shown by the arrow in FIG.

[0122] The analysis results using an EDX device for a multilayer ceramic capacitor different from that of the present embodiment shown in FIG. 9 will be described with reference to FIG. 10 . In FIG. 10 , (a) shows the Al detection results using an EDX device from the tip side portion to a portion of the base side portion shown in FIG. 9 , and (b) shows the Cu detection results using an EDX device at the same location as (a). Using the EDX device, a line analysis was performed at the laminate interface 51a from the tip side portion 431 to a portion of the base side portion 42. The Al or Cu detection results in FIG. 10 differ from the Al or Cu detection results in FIG. 5 . As shown in (a) of FIG. 10 , the Al content in the tip side portion 431 is approximately the same as the Al content in the base side portion 42. Al is one of the glass components of the glass 60. Therefore, it can be seen that the glass 60 content in the tip side portion 431 is approximately the same as the glass 60 content in the base side portion 42. Furthermore, the cavity 54 shown in FIG. 5 is not present in the tip side portion 431. From this, it can be seen that the range of the bonding area (included in the distal interface 531) between the distal side portion 431 and the laminate 12 via the glass 60 is approximately the same as the range of the bonding area (included in the proximal interface 52) between the proximal side portion 42 and the laminate 12 via the glass 60. Furthermore, as shown in (b) of FIG. 10 , portions with a low Cu content are found from the distal side portion 431 to the proximal side portion 42. On the other hand, as shown in (a) of FIG. 10 , Al is present evenly from the distal side portion 431 to the proximal side portion 42, and it can be seen that the distal side portion 431 and the proximal side portion 42 are bonded to the laminate 12 mainly via the glass 60 from the distal interface 531 to the proximal interface 52. From the above, it can be seen that the range of the adhesive region (included in the distal interface 531) between the distal side portion 431 and the laminate 12 via the glass 60 or metal particles is approximately the same as the range of the adhesive region (included in the proximal interface 52) between the proximal side portion 42 and the laminate 12 via the glass 60 or metal particles. Furthermore, it can be seen that the distal side portion 431 and the proximal side portion 42 are adhered to the laminate 12 over almost the entire area.

[0123] (2) In this embodiment, the content of glass 60 present at the tip-side interface 53 is less than the content of glass 60 present at the base-side interface 52. In other words, the continuity of glass 60 at the tip-side interface 53 is less than the continuity of glass 60 at the base-side interface 52. Here, the larger the content of glass 60 in the wraparound electrode portion 41, the greater the adhesive strength to the laminate 12 tends to be. Therefore, with the above configuration, the adhesive strength between the tip-side portion 43 and the laminate 12 at the tip-side interface 53 is less than the adhesive strength between the base-side portion 42 and the laminate 12 at the base-side interface 52. Therefore, it is possible to provide a multilayer ceramic capacitor 10 in which stress can be alleviated by the tip-side portion 43 when stress is applied to the multilayer ceramic capacitor 10.

[0124] (3) In this embodiment, the tip side portion 43 is located at the center position P C The tip side portion 43 is located closer to the tip than the center position P. Such a tip side portion 43 can prevent stress from being directed toward the inside of the laminate 12. Furthermore, the proportion of the tip side portion 43 in the wraparound electrode portion 41 is kept relatively small, and even if the tip side portion 43 peels off or chips due to stress, damage to the external electrode 30 is unlikely to be significant. For example, if the tip side portion 43 is located closer to the center position P than the tip side of the laminate interface 51, the external electrode 30 is unlikely to be damaged. C In this case, the tip side portion 43 occupies a large proportion of the wraparound electrode portion 41, and if the tip side portion 43 peels off or chips due to stress, the external electrode 30 is likely to be severely damaged.

[0125] (4) In this embodiment, the ratio of the distance of the tip-side adhesive interface 53a to the distance of the tip-side interface 53 is smaller than the ratio of the distance of the base-side adhesive interface 52a to the distance of the base-side interface 52. This makes it possible to make the tip-side portion 43 somewhat more likely to peel from the laminate 12 and to bend somewhat when stress is applied to the wraparound electrode portion 41. This allows the stress to be dispersed, thereby preventing cracks from occurring in the ceramic layers 14 of the laminate 12 and, ultimately, in the internal electrode layers 16. Furthermore, the ratio of the distance of the tip-side adhesive interface 53a to the distance of the tip-side interface 53 is prevented from becoming too large, thereby preventing damage to the external electrode 30 due to large peeling of the tip-side portion 43, which is prone to peeling. The same effects as described above can also be obtained by, for example, setting the ratio of the distance of the tip-side adhesive interface 53a to the distance of the tip-side interface 53 to, for example, 10% to 50%, and by setting the ratio of the distance of the tip-side non-bonded interface 53b to the distance of the tip-side interface 53 to, for example, 5% to 50%, etc.

[0126] (5) In this embodiment, the distance of the tip-side adhesive interface 53a / the distance of the laminate interface 51 can be said to be smaller than the distance of the base-side adhesive interface 52a / the distance of the laminate interface 51. In this case, as described above, it is possible to prevent cracks from occurring in the ceramic layers 14 of the laminate 12, and ultimately in the internal electrode layers 16. Furthermore, it is possible to prevent the distance of the tip-side adhesive interface 53a from becoming too large, and to prevent the tip side portion 43, which is prone to peeling, from peeling off significantly, thereby damaging the external electrode 30. Furthermore, it is possible to further obtain the same effect as described above by setting the distance of the tip-side non-adhesive interface 53b / the distance of the laminate interface 51 to, for example, 1.5% or more and 15% or less.

[0127] (6) In the present embodiment, the total distance of at least one distal adhesive interface 53a and at least one proximal adhesive interface 52a along the laminate interface 51 is, for example, 40% to 70% of the distance of the laminate interface 51. This makes it possible to adjust the adhesive strength between the entire wraparound electrode portion 41 and the laminate 12 to a degree that can disperse stress while suppressing large peeling and large chipping of the distal side portion 43.

[0128] (7) In this embodiment, the distance over which each glass domain 61 contacts the laminate interface 51 is, for example, 0.1% to 10% of the distance of the laminate interface 51. Furthermore, the thickness T2 of each glass domain 61 is, for example, 0.1% to 20% of the thickness T1 of the wraparound electrode portion 41. By setting each glass domain 61 as described above, the adhesive strength between the wraparound electrode portion 41 and the laminate 12 can be appropriately adjusted.

[0129] 4. Experimental Examples Next, experimental examples will be described. As experimental examples, Example 1 and Comparative Examples 1 and 2 were performed. Fig. 11 is a partially enlarged cross-sectional view of the base electrode layer and the laminate when the plating layer is omitted from the multilayer ceramic capacitor of Comparative Example 1. Fig. 12 is a partially enlarged cross-sectional view of the base electrode layer and the laminate when the plating layer is omitted from the multilayer ceramic capacitor of Comparative Example 2.

[0130] (1) Samples The samples of Example 1 and Comparative Examples 1 and 2 are described below.

[0131] (Sample of Example 1) A multilayer ceramic capacitor according to the present embodiment shown in FIGS. 3 and 4 was prepared as a basic sample of Example 1. The wraparound electrode portion 41 of the basic sample of Example 1 has a base end portion 42 and a tip end portion 43, as shown in FIGS. 3 and 4. The multilayer ceramic capacitor of Example 1 has an L dimension of 1.60 mm, a W dimension of 0.791 mm, and a T dimension of 0.791 mm. The length e of the e dimension is 0.40 mm. The G dimension between the tip end portion 43 on the first end face 12e side and the tip end portion 43 on the second end face 12f side is 0.80 mm (FIG. 1). The tip side interface 53 has an L2 of 0.10 mm. The laminate interface 51 has a distance L1 of 0.34 mm. Additionally, as variations of the basic sample of Example 1, several other samples were prepared in which the distance L2 was varied from 0.08 mm to 0.09 mm.

[0132] (Sample of Comparative Example 1) A multilayer ceramic capacitor shown in FIG. 11 was prepared as a sample of Comparative Example 1. The sample of Comparative Example 1 is the same as the sample of FIG. 9. As shown in FIG. 11, the wraparound electrode portion 41 of the sample of Comparative Example 1 has a base end side portion 42 and a tip end side portion 431. Unlike the tip end side portion 43 of Example 1, the tip end side portion 431 of Comparative Example 1 does not have a tip side non-bonded interface, as shown in FIGS. 9 and 11. Therefore, the laminate 12 and the wraparound electrode portion 41 are bonded via the glass 60 over substantially the entire laminate interface 51a (the base end side interface 52 and the tip end side interface 531). In other respects, the sample is the same as the basic sample of Example 1.

[0133] (Sample of Comparative Example 2) A multilayer ceramic capacitor shown in FIG. 12 was prepared as a sample of Comparative Example 2. The multilayer ceramic capacitor of Comparative Example 2 was provided with a separation portion 57. The separation portion 57 was provided on the tip side, continuing from the base end side portion 42 of the wraparound electrode portion 41. The separation portion 57 was formed so that the separation distance S from the surface of the laminate 12 (first main surface 12a in the example of FIG. 12) was S = 3.0 mm. The laminate 12 and the base end side portion 42 were bonded via the glass 60 over substantially the entire base end side interface 52 (laminate interface 51b). Meanwhile, the laminate 12 and the wraparound electrode portion 41 were completely separated and not bonded at the separation portion 57. The rest of the sample was the same as the basic sample of Example 1.

[0134] (2) Evaluation of Stress in Samples For Example 1, Comparative Example 1, and Comparative Example 2, an external force was applied to each sample using analytical simulation software, and the resulting stress was compared. The external force conditions were as follows: A solder-mounted multilayer ceramic capacitor model was used, in which the second main surface 12b of Example 1, Comparative Example 1, and Comparative Example 2 was opposed to one surface of a mounting substrate having a thickness of 1.6 mm. Next, the center of the other surface on which the multilayer ceramic capacitor was not mounted was used as a fixed end, and a load was applied to both ends of the substrate toward the other surface, bending the mounting substrate. The amount of bending generated in the mounting substrate was 1.0 mm.

[0135] (3) Results The results of stress evaluation are shown in Fig. 13. In Fig. 13, (a) is a stress distribution diagram for the basic sample of Example 1, (b) is a stress distribution diagram for the sample of Comparative Example 1, and (c) is a stress distribution diagram for the sample of Comparative Example 2.

[0136] 11, in the sample of Comparative Example 1, a strong stress directed toward the inside of the laminate 12 was locally generated in a part of the tip side portion 431 of the first base electrode layer 32a (the portion circled by a dashed-dotted line). Similarly, a strong stress directed toward the inside of the laminate 12 was locally generated in the tip side portion of the second base electrode layer 32b.

[0137] As shown in (c) of Figure 13, in the sample of Comparative Example 2 shown in Figure 12, strong stress directed toward the inside of the laminate 12 was generated locally at least near the contact point between the separated portion 57 of the first base electrode layer 32a and the base end side portion 42 (the area surrounded by the dotted line circle).

[0138] As shown in FIG. 13A , in the basic sample of Example 1 shown in FIGS. 3 and 4 , no localized strong stress was generated at the laminate interface 51 between the first base electrode layer 32 a and the laminate 12, and the stress was dispersed. Similarly, no localized strong stress was generated at the laminate interface 51 between the second base electrode layer 32 b and the laminate 12, and the stress was dispersed. That is, in both the first and second base electrode layers 32 a and 32 b of the basic sample of Example 1, the localized strong stress directed toward the inside of the laminate 12, as shown in the sample of Comparative Example 1 ( FIG. 13B ) and the sample of Comparative Example 2 ( FIG. 13C ), was suppressed at the laminate interface 51. This demonstrates that partial bonding between the tip side portion 43 and the laminate 12 can alleviate stress applied to the multilayer ceramic capacitor 10.

[0139] The multilayer ceramic capacitor of Example 1 achieved the following parameters. (a) It was found that stress could be alleviated by setting the distance L2 (0.08 mm to 0.10 mm) of the tip-side interface 53 relative to the distance L1 (0.34 mm) of the laminate interface 51. In this case, the distance L2 of the tip-side interface 53 relative to the distance L1 of the laminate interface 51 was 23.5% to 29.4%. (b) In the wraparound electrode portion 41, the content of the glass domain 61 (glass 60) relative to the total content of the glass domain 61 (glass 60), metal particles, various additives, etc. was 5% to 20% by weight. (c) The total distance of the multiple tip-side adhesive interfaces 53a was 10% to 50% of the distance L2 of the tip-side interface 53. The total distance of the tip-side adhesive interfaces 53a was 2% to 15% of the distance L1 of the laminate interface 51. (d) The separation distance SE between the laminate 12 and the distal side portion 43 was 2 μm or more and 10 μm or less. (e) The total distance of the plurality of distal non-bonded interfaces 53b was 5% or more and 50% or less of the distance L2 of the distal interface 53. The total distance of the plurality of distal non-bonded interfaces 53b was 1.5% or more and 15% or less of the distance L1 of the laminate interface 51. (f) The total distance of the plurality of proximal adhesive interfaces 52a was 40% or more and 80% or less of the distance L6 of the proximal interface 52. The total distance of the plurality of proximal adhesive interfaces 52a was 35% or more and 75% or less of the distance L1 of the laminate interface 51. (g) The total distance of the plurality of distal adhesive interfaces 53a and the plurality of proximal adhesive interfaces 52a was 40% or more and 70% or less of the distance L1 of the laminate interface 51. (h) The thickness T2 was 0.5% or more and 17% or less of the thickness T1. (i) The distance over which one glass domain 61 contacts along the laminate interface 51 was, for example, 1.0% or more and 6.0% or less of the distance L1 of the laminate interface 51 .

[0140] As described above, although the embodiments of the present invention have been disclosed in the above description, the present invention is not limited thereto. In other words, various modifications can be made to the above-described embodiments in terms of mechanism, shape, material, quantity, position, arrangement, etc., without departing from the scope of the technical idea and purpose of the present invention, and such modifications are included in the present invention.

[0141] <Other Modifications> (1) Regarding the External Electrode In the above embodiment, the external electrode 30 includes the base electrode layer 32 and the plating layer 34 on the base electrode layer 32. However, the configuration of the external electrode 30 is not limited to this, and the external electrode may include only the base electrode layer 32 without including the plating layer 34. This is the same as the above embodiment except that the plating layer 34 is not formed.

[0142] (2) Adhesion Interface In the above embodiment, at the front end side adhesion interface 53a, the laminate 12 is adhered to the front end side portion 43 not only via the glass domain 61 but also via metal particles or the like. Therefore, the distance of the front end side adhesion interface 53a is E From position P G Distance L5+distance L3a to position P H From tip position P B The distance between the tip side adhesive interface 53a and the distal end portion 43 is the total distance (distance L5+distance L3a+distance L3b) including the distance L3a to the distal end portion 43. However, the tip side adhesive interface 53a may be an interface where the laminate 12 is adhered to the distal end portion 43 via a glass domain 61, rather than via a metal particle or the like. In this case, the distance between the tip side adhesive interface 53a is the total distance (distance L3a+distance L3b) of the distance L3a and the distance L3b.

[0143] Similarly, in the above embodiment, at the base-side adhesive interface 52a, the laminate 12 is bonded to the base-side portion 42 via the glass domain 61, metal particles, etc. Therefore, the distance of the base-side adhesive interface 52a is A to the end position P D The base-side adhesive interface 52a may be an interface where the laminate 12 is bonded to the base-side portion 42 via a glass domain 61, rather than via a metal particle or the like. In this case, the distance of the base-side adhesive interface 52a is the total distance of the distances L7a to L7e.

[0144] <1> A multilayer ceramic capacitor comprising: a laminate including a plurality of laminated ceramic layers and a plurality of internal electrode layers, the laminate including first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, and first and second end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction; and external electrodes connected to the internal electrode layers at the first end surfaces and the second end surfaces, wherein the external electrodes include a base electrode layer formed on the laminate, the base electrode layer including a conductive metal and glass, the base electrode layer having end surface electrode portions formed on the laminate at the first end surfaces and the second end surfaces, and wraparound electrode portions that are continuous with the end surface electrode portions and are formed on the laminate by wrapping around from the first end surfaces and the second end surfaces to at least one of the first main surface, the second main surface, the first side surfaces, and the second side surfaces, a base end side portion located on the side of the first end face and the second end face; and a tip end side portion that is continuous with the base end side portion and is located on the tip side, away from the first end face and the second end face, with respect to the base end side portion, wherein a tip end side interface of the laminate that faces the tip end side portion among laminate interfaces of the laminate that face the wraparound electrode portion includes at least one tip end side adhesive interface where the laminate is bonded to the tip end side portion, and at least one tip end side non-adhesive interface where the laminate is not bonded to the tip end side portion.

[0145] <2> The multilayer ceramic capacitor according to <1>, wherein an interface of the laminate facing the base end portion among the interfaces of the laminate is a base end side interface, and in a cross-sectional view perpendicular to the first end face and the second end face, a content of the glass present at the tip end side interface is less than a content of the glass present at the base end side interface.

[0146] <3> The multilayer ceramic capacitor according to <1> or <2>, wherein an interface of the laminate facing the base end portion among the interfaces of the laminate is a base end side interface, and in a cross-sectional view perpendicular to the first end face and the second end face, the continuity of the glass at the tip end side interface is smaller than the continuity of the glass at the base end side interface.

[0147] <4> The multilayer ceramic capacitor according to any one of <1> to <3>, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, the tip side portion is located on the tip side of a center position between a base end position closest to the first end face and the second end face and a tip position farthest from the first end face and the second end face at the interface of the laminate.

[0148] <5> The multilayer ceramic capacitor according to any one of <1> to <4>, wherein an interface of the laminate facing the base end portion among the laminate interfaces is a base end interface, the base end interface includes at least one base end side adhesive interface at which the laminate is bonded to the base end portion mainly via the glass, and in a cross-sectional view perpendicular to the first end face and the second end face, a proportion of a distance of the at least one tip end side adhesive interface to a distance of the tip end side interface is smaller than a proportion of a distance of the at least one base end side adhesive interface to a distance of the base end side interface.

[0149] <6> The multilayer ceramic capacitor according to any one of <1> to <5>, wherein an interface of the laminate facing the base end portion among the laminate interfaces is a base end interface, the base end interface includes at least one base end adhesive interface at which the laminate is bonded to the base end portion mainly via the glass, and in a cross-sectional view perpendicular to the first end face and the second end face, a proportion of a distance of the at least one tip end adhesive interface to a distance of the laminate interface is smaller than a proportion of a distance of the at least one base end adhesive interface to a distance of the laminate interface.

[0150] <7> The multilayer ceramic capacitor according to any one of <1> to <6>, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, a distance of the at least one tip-side adhesive interface is 10% to 50% of a distance of the tip-side interface.

[0151] <8> The multilayer ceramic capacitor according to any one of <1> to <7>, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, a distance of the at least one tip-side adhesive interface is 2% to 15% of a distance of the laminate interface.

[0152] <9> The multilayer ceramic capacitor according to any one of <1> to <8>, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, a distance of the at least one tip-side non-bonded interface is 5% to 50% of a distance of the tip-side interface.

[0153] <10> The multilayer ceramic capacitor according to any one of <1> to <9>, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, a distance of the at least one tip-side non-bonded interface is 1.5% to 15% of a distance of the laminate interface.

[0154] <11> The multilayer ceramic capacitor according to any one of <1> to <10>, wherein an interface of the laminate facing the base end portion among the laminate interfaces is a base end interface, the base end interface includes at least one base end adhesive interface at which the laminate is bonded to the base end portion mainly via the glass, and in a cross-sectional view perpendicular to the first end face and the second end face, a total distance of the at least one tip end adhesive interface and the at least one base end adhesive interface is 40% or more and 70% or less of a distance of the laminate interface.

[0155] <12> The multilayer ceramic capacitor according to any one of <1> to <11>, wherein the glass includes a plurality of glass domains, and the distance of each glass domain in contact with the laminate interface is 0.1% to 10% of the distance of the laminate interface.

[0156] <13> The multilayer ceramic capacitor according to any one of <1> to <12>, wherein the glass includes a plurality of glass domains, and a thickness of each glass domain in contact with the laminate interface in a direction perpendicular to the laminate interface is 0.1% to 20% of a thickness of the wraparound electrode portion in the direction perpendicular to the laminate interface.

[0157] <14> The multilayer ceramic capacitor according to any one of <1> to <13>, wherein the external electrodes include a plating layer disposed on the base electrode layer.

[0158] <15> A multilayer ceramic capacitor comprising: a laminate including a plurality of laminated ceramic layers and a plurality of internal electrode layers, the laminate including first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, and first and second end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction; and external electrodes connected to the internal electrode layers at the first end surfaces and the second end surfaces, wherein the external electrodes include a base electrode layer formed on the laminate, the base electrode layer including a conductive metal and glass, and the base electrode layer has end surface electrode portions formed on the laminate on the first end surface and the second end surface, and wraparound electrode portions that are continuous with the end surface electrode portions and are formed on the laminate by wrapping around from the first end surface and the second end surface to at least one of the first main surface, the second main surface, the first side surface, and the second side surface, a multilayer ceramic capacitor, wherein, in the wraparound electrode portion, a position closest to the first end face and the second end face is defined as a base end position, a position farthest from the first end face and the second end face is defined as a tip end position, and a position between the base end position and the tip end position is defined as a center position, an adhesion area where the wraparound electrode portion is adhered to the laminate is smaller between the center position and the tip end position than between the base end position and the center position.

[0159] REFERENCE SIGNS LIST 10: Multilayer ceramic capacitor 12: Laminate 12a, 12b: First and second main surfaces 12c, 12d: First and second side surfaces 12e: First and second end surfaces 14: Ceramic layer 15a: Effective layer portion 15b, 15b: First and second outer layer portions 16: Internal electrode layer 16a, 16b: First and second internal electrode layer 30: External electrode 30a, 30b: First and second external electrode 32: Base electrode layer 32a, 32b: First and second base electrode layer 34: Plating layer 34a, 34b: First and second plating layer 40: End surface electrode portion 41: Wrapping electrode portion 42: Base end side portion 43: Tip side portion 51: Laminate interface 51a: Laminate interface 51b: Laminate interface 52: Base end side interface 52a: Base end side adhesive interface 53: Tip side interface 53a: Tip side adhesive interface 53b: Tip side non-adhesive interface 54: Cavity 57: Separation portion 60: Glass 61: Glass domain 71: Base electrode layer paste 71a: Base electrode layer paste 72: Metal powder 72a: Metal powder 73: Glass powder 75: Paste tank 431: Tip side portion 531: Tip side interface a1: Major axis (major axis of metal powder) b1: Minor axis (minor axis of metal powder) a2: Major axis (major axis of conventional metal powder) b2: Minor axis (minor axis of conventional metal powder) dg: Equivalent sphere diameter (equivalent sphere diameter of glass powder) P A : Proximal position P B :Tip position P C : Center position P D : End position P E ~P R: Position L1 to L8 : Distance S : Separation distance SE : Separation distance T1, T2 : Thickness x : Height direction y : Width direction z : Length direction

Claims

1. A multilayer ceramic capacitor comprising: a laminate including a plurality of laminated ceramic layers and a plurality of internal electrode layers, the laminate including first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, and first and second end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction; and external electrodes connected to the internal electrode layers at the first end surfaces and the second end surfaces, wherein the external electrodes include a base electrode layer formed on the laminate, the base electrode layer including a conductive metal and glass, the base electrode layer having end surface electrodes formed on the laminate at the first end surfaces and the second end surfaces, and wraparound electrode portions that are continuous with the end surface electrodes and are formed on the laminate by wrapping around from the first end surfaces and the second end surfaces to at least one of the first main surface, the second main surface, the first side surfaces, and the second side surfaces, and the wraparound electrode portions are a base end side portion located on the side of the first end face and the second end face; and a tip end side portion that is continuous with the base end side portion and is located on the tip side, away from the first end face and the second end face, with respect to the base end side portion, wherein a tip end side interface of the laminate that faces the tip end side portion among laminate interfaces of the laminate that face the wraparound electrode portion includes at least one tip end side adhesive interface where the laminate is bonded to the tip end side portion, and at least one tip end side non-adhesive interface where the laminate is not bonded to the tip end side portion.

2. The multilayer ceramic capacitor according to claim 1, wherein the interface of the laminate facing the base end side portion is the base end side interface, and in a cross-sectional view perpendicular to the first end face and the second end face, the content of the glass present at the tip end side interface is less than the content of the glass present at the base end side interface.

3. A multilayer ceramic capacitor according to claim 1 or 2, wherein the interface of the laminate facing the base end side portion is a base end side interface, and in a cross-sectional view perpendicular to the first end face and the second end face, the continuity of the glass at the tip end side interface is smaller than the continuity of the glass at the base end side interface.

4. A multilayer ceramic capacitor according to any one of claims 1 to 3, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, the tip side portion is located on the tip side of the laminate interface relative to a center position between a base end position closest to the first end face and the second end face and a tip position farthest from the first end face and the second end face.

5. A multilayer ceramic capacitor according to any one of claims 1 to 4, wherein the interface of the laminate facing the base end portion is a base end interface, the base end interface includes at least one base end adhesive interface at which the laminate is bonded to the base end portion mainly via the glass, and in a cross section perpendicular to the first end face and the second end face, the proportion of the distance of the at least one tip end adhesive interface to the distance of the tip end interface is smaller than the proportion of the distance of the at least one base end adhesive interface to the distance of the base end interface.

6. A multilayer ceramic capacitor according to any one of claims 1 to 5, wherein the interface of the laminate facing the base end portion is a base end interface, the base end interface includes at least one base end adhesive interface at which the laminate is bonded to the base end portion mainly via the glass, and in a cross section perpendicular to the first end face and the second end face, the proportion of the distance of the at least one tip end adhesive interface to the distance of the laminate interface is smaller than the proportion of the distance of the at least one base end adhesive interface to the distance of the laminate interface.

7. A multilayer ceramic capacitor according to any one of claims 1 to 6, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, the distance of the at least one tip-side adhesive interface is 10% to 50% of the distance of the tip-side interface.

8. A multilayer ceramic capacitor according to any one of claims 1 to 7, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, the distance of the at least one front-end adhesive interface is 2% or more and 15% or less of the distance of the laminate interface.

9. A multilayer ceramic capacitor according to any one of claims 1 to 8, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, the distance of the at least one tip-side non-bonded interface is 5% to 50% of the distance of the tip-side interface.

10. A multilayer ceramic capacitor as described in any one of claims 1 to 9, wherein, in a cross-sectional view perpendicular to the first end face and the second end face, the distance of the at least one tip-side non-bonded interface is 1.5% or more and 15% or less of the distance of the laminate interface.

11. A multilayer ceramic capacitor according to any one of claims 1 to 10, wherein the interface of the laminate facing the base end portion is a base end interface, the base end interface includes at least one base end adhesive interface where the laminate is bonded to the base end portion mainly via the glass, and in a cross section perpendicular to the first end face and the second end face, the total distance of the at least one tip end adhesive interface and the at least one base end adhesive interface is 40% or more and 70% or less of the distance of the laminate interface.

12. A multilayer ceramic capacitor according to any one of claims 1 to 11, wherein the glass comprises a plurality of glass domains, and the distance each glass domain contacts the laminate interface is between 0.1% and 10% of the distance at the laminate interface.

13. A multilayer ceramic capacitor according to any one of claims 1 to 12, wherein the glass includes a plurality of glass domains, and the thickness of each glass domain in contact with the laminate interface in a direction perpendicular to the laminate interface is 0.1% to 20% of the thickness of the wraparound electrode portion in a direction perpendicular to the laminate interface.

14. A multilayer ceramic capacitor according to any one of claims 1 to 13, wherein the external electrodes include a plating layer disposed on the base electrode layer.

15. A multilayer ceramic capacitor comprising: a laminate including a plurality of laminated ceramic layers and a plurality of internal electrode layers, the laminate including first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, and first and second end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction; and external electrodes connected to the internal electrode layers at the first end surfaces and the second end surfaces, wherein the external electrodes include a base electrode layer formed on the laminate, the base electrode layer including a conductive metal and glass, and the base electrode layer has end surface electrode portions formed on the laminate at the first end surface and the second end surface, and wraparound electrode portions that are continuous with the end surface electrode portions and are formed on the laminate by wrapping around from the first end surface and the second end surface to at least one of the first main surface, the second main surface, the first side surface, and the second side surface, a multilayer ceramic capacitor, wherein, in the wraparound electrode portion, a position closest to the first end face and the second end face is defined as a base end position, a position farthest from the first end face and the second end face is defined as a tip end position, and a position between the base end position and the tip end position is defined as a center position, an adhesion area where the wraparound electrode portion is adhered to the laminate is smaller between the center position and the tip end position than between the base end position and the center position.

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