Multilayer ceramic electronic component

Abstract

The present invention provides a multilayer ceramic capacitor which has high adhesion strength between an external electrode and a spacer and exhibits excellent durability when mounted. A multilayer ceramic electronic component 1 according to the present invention is provided with: a capacitor main body 1A that is provided with a multilayer body 2 and two external electrodes 3 which are disposed on two end surfaces of the multilayer body 2, are connected to an internal electrode layer 15, and extend to two main surfaces of the multilayer body 2 so as to partially cover the main surfaces; and two spacers 4 that are disposed on both end surface sides of one main surface side of the capacitor main body 1A, sandwiching the external electrodes 3 partially covering the main surfaces. The spacers 4 are longer than the external electrodes 3 covering the main surfaces, in the length direction, and each contain an intermetallic compound which contains at least one of Cu and Ni as a high melting point metal and Sn as a low melting point metal, and a protective material 6. If each of the spacers 4 is divided into two parts in the length direction along a line extending in a stacking direction, the content ratio of the protective material 6 is higher in a region that is closer to a central part of the capacitor main body 1A in the length direction than in a region that is farther from the central part of the capacitor main body 1A.

Description

Multilayer ceramic electronic components

[0001] The present invention relates to a multilayer ceramic electronic component such as a multilayer ceramic capacitor.

[0002] Multilayer ceramic electronic components such as multilayer ceramic capacitors are widely used in various electronic devices, such as mobile terminal devices such as mobile phones and personal computers. A multilayer ceramic capacitor comprises a rectangular parallelepiped laminate in which dielectric layers and internal electrode layers are alternately stacked, and external electrodes formed on both opposing ends of the laminate.

[0003] A multilayer ceramic capacitor has an inner layer portion in which dielectric layers and internal electrodes are alternately stacked, and dielectric layers are disposed on the top and bottom of the inner layer portion as outer layers to form a rectangular parallelepiped laminate, and external electrodes are provided on both longitudinal end faces of the laminate to form a capacitor body.

[0004] Furthermore, in order to suppress the occurrence of so-called "squeak noise," a multilayer ceramic capacitor is known that includes a spacer formed on the side of the capacitor body that is mounted on the substrate so as to cover part of the external electrodes.

[0005] Japanese Patent Application Laid-Open No. 2015-216337

[0006] However, if the adhesive strength between the capacitor body and the spacer is weak, the spacer may peel off, and the durability when mounted is insufficient.

[0007] An object of the present invention is to provide a multilayer ceramic capacitor that has a high adhesive strength between the capacitor body and the spacer and is highly durable when mounted.

[0008] In order to solve the above problems, the present invention provides a capacitor body including: a laminate in which dielectric layers and internal electrode layers are alternately laminated, the laminate having two main surfaces opposing each other in a lamination direction, two end faces opposing each other in a length direction intersecting the lamination direction, and two side surfaces opposing each other in a width direction intersecting the lamination direction and the length direction; and two external electrodes disposed on the two end faces, respectively, connected to the internal electrode layers, and extending to the two main surfaces to cover parts of the main surfaces and the two side surfaces to cover parts of the side surfaces; and two spacers arranged on one end face side and the other end face side, respectively, on one end face side or one side face side of the main surface, with the external electrode covering the part of the main surface or the part of the side face sandwiched therebetween, each of the spacers being longer in the longitudinal direction than the external electrode covering the one main surface, and containing a metal component and a protective material, and when divided into two in the longitudinal direction along a line extending in the stacking direction, a region closer to the longitudinal center of the capacitor body has a higher content of the protective material than a region further away.

[0009] According to the present invention, it is possible to provide a multilayer ceramic capacitor having a high adhesive strength between the capacitor body and the spacer, and having excellent durability when mounted.

[0010] 1 is a schematic perspective view of a multilayer ceramic capacitor 1. FIG. 2 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line II-II in FIG. 1. FIG. 3 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line III-III in FIG. 1. FIG. 4 is an enlarged view of a spacer 4 portion in the cross-sectional view of the multilayer ceramic capacitor 1 in FIG. 2. FIG. 5 is a flowchart illustrating a method for manufacturing the multilayer ceramic capacitor 1. FIG. 6 is a diagram illustrating a laminate manufacturing step S1 and an external electrode forming step S2. FIG. 7 is a diagram illustrating a protective material and reinforcing material paste arranging step S3, a spacer paste arranging step S4, and a reflow step S5. FIG. 8 is a flowchart illustrating a protective material 6 and reinforcing material forming step in a modified example. FIG. 9 is a diagram illustrating a protective material 6 and reinforcing material forming step in a modified example.

[0011] Hereinafter, a multilayer ceramic capacitor 1 will be described as an embodiment of the multilayer ceramic electronic component of the present invention, but the present invention is not limited thereto. Furthermore, the drawings may be drawn in a simplified and schematic manner to explain the contents of the invention, and the dimensional ratios of the depicted components or between the components may not match the dimensional ratios of those components described in the specification. Furthermore, components described in the specification may be omitted in the drawings, or the number of components may be omitted.

[0012] Fig. 1 is a schematic perspective view of a multilayer ceramic capacitor 1 according to an embodiment. Fig. 2 is a cross-sectional view of the multilayer ceramic capacitor 1 according to an embodiment taken along line II-II in Fig. 1. Fig. 3 is a cross-sectional view of the multilayer ceramic capacitor 1 according to an embodiment taken along line III-III in Fig. 1.

[0013] The multilayer ceramic capacitor 1 has a substantially rectangular parallelepiped shape and includes a capacitor body 1A including a laminate 2 and a pair of external electrodes 3 provided on both ends of the laminate 2, a spacer 4 attached to the capacitor body 1A and including a protective material 6, and a reinforcing material 5 disposed between the two spacers 4. The laminate 2 also includes an inner layer portion 11 in which dielectric layers 14 and internal electrode layers 15 are laminated.

[0014] In the following description, the terms used to represent the orientation of the multilayer ceramic capacitor 1 are: a length direction L, which is the direction in which a pair of external electrodes 3 are provided in the multilayer ceramic capacitor 1; a stacking direction T, which is the direction in which the dielectric layers 14 and the internal electrode layers 15 are stacked; and a width direction W, which is the direction intersecting both the length direction L and the stacking direction T. In the embodiment, the width direction W is perpendicular to both the length direction L and the stacking direction T.

[0015] (Outer Surfaces of Laminate 2) Of the six outer surfaces of the laminate 2, a pair of outer surfaces facing each other in the stacking direction T will be referred to as the first main surface A1 and the second main surface A2, a pair of outer surfaces facing each other in the width direction W will be referred to as the first side surface B1 and the second side surface B2, and a pair of outer surfaces facing each other in the length direction L will be referred to as the first end surface C1 and the second end surface C2. Note that when there is no need to particularly distinguish between the first main surface A1 and the second main surface A2, they will be collectively referred to as the main surface A; when there is no need to particularly distinguish between the first side surface B1 and the second side surface B2, they will be collectively referred to as the side surface B; and when there is no need to particularly distinguish between the first end surface C1 and the second end surface C2, they will be collectively referred to as the end surface C.

[0016] The laminate 2 preferably has rounded ridges R1 including corners. The ridges R1 are the portions where two surfaces of the laminate 2, i.e., the main surface A and the side surface B, the main surface A and the end surface C, or the side surface B and the end surface C, intersect.

[0017] (Laminate 2) The laminate 2 includes an inner layer portion 11 that forms capacitance, an outer layer portion 12 that is arranged to sandwich the inner layer portion 11 in the stacking direction T, and a side gap portion 16 that is arranged to sandwich the inner layer portion 11 and the outer layer portion 12 in the width direction W.

[0018] (Inner Layer Portion 11) The inner layer portion 11 includes dielectric layers 14 and internal electrode layers 15 alternately stacked along the stacking direction T.

[0019] (Dielectric Layer 14) The dielectric layer 14 is made of a ceramic material, such as BaTiO ３ A dielectric ceramic containing the above as its main component is used.

[0020] (Internal Electrode Layer 15) The internal electrode layer 15 includes a plurality of first internal electrode layers 15a and a plurality of second internal electrode layers 15b. The first internal electrode layers 15a and the second internal electrode layers 15b are alternately arranged. The first internal electrode layer 15a includes a first opposing portion 152a opposing the second internal electrode layer 15b and a first lead portion 151a extending from the first opposing portion 152a toward the first end face C1. An end of the first lead portion 151a is exposed at the first end face C1 and electrically connected to the first external electrode 3a described below. The second internal electrode layer 15b includes a second opposing portion 152b opposing the first internal electrode layer 15a and a second lead portion 151b extending from the second opposing portion 152b to the second end face C2. An end of the second lead portion 151b is electrically connected to the second external electrode 3b described below. Charges are stored in the first opposing portions 152a of the first internal electrode layers 15a and the second opposing portions 152b of the second internal electrode layers 15b.

[0021] The internal electrode layers 15 are preferably formed from a metal material such as nickel (Ni), copper (Cu), silver (Ag), palladium (Pd), a silver-palladium (Ag-Pd) alloy, or gold (Au).

[0022] (Outer Layer Portion 12) The outer layer portion 12 can be formed from the same material as the dielectric layer 14 of the inner layer portion 11.

[0023] (Side gap portion 16) The side gap portion 16 is arranged to sandwich the inner layer portion 11 and the outer layer portion 12 in the width direction W, and includes a first side gap portion 16a that forms the first side surface B1 of the multilayer ceramic capacitor 1, and a second side gap portion 16b that forms the second side surface B2 of the multilayer ceramic capacitor 1. The side gap portion 16 can be formed from the same material as the dielectric layer 14.

[0024] (External electrode 3) The external electrode 3 includes a first external electrode 3a provided on the first end face C1 and a second external electrode 3b provided on the second end face C2. The external electrode 3 covers not only the end face C but also a part of the main face A and the side face B that are continuous with the end face C.

[0025] As described above, the end of the first lead portion 151a of the first internal electrode layer 15a is exposed at the first end face C1 and is electrically connected to the first external electrode 3a. Also, the end of the second lead portion 151b of the second internal electrode layer 15b is exposed at the second end face C2 and is electrically connected to the second external electrode 3b. This results in a structure in which multiple capacitor elements are electrically connected in parallel between the first external electrode 3a and the second external electrode 3b.

[0026] The external electrode 3 includes, for example, a base electrode layer 30 and a plating layer 31. However, it is not always necessary for the external electrode 3 to have such a layered structure.

[0027] The base electrode layer 30 is formed by, for example, applying and baking a conductive paste containing copper (Cu). The base electrode layer 30 may also contain glass or a ceramic material. However, the configuration of the base electrode layer 30 is not limited to this.

[0028] The plating layer 31 includes a nickel (Ni) plating layer 31 a disposed on the surface of the base electrode layer 30, and a tin (Sn) plating layer 31 b disposed on the surface of the nickel (Ni) plating layer 31 a. Note that the configuration of the plating layer 31 is not limited to this.

[0029] (Spacer 4) The spacer 4 includes a pair of first and second spacers 4a and 4b. The first spacer 4a is disposed on one end face C1 in the longitudinal direction L of the second main surface A2, which is the mounting surface of the capacitor body 1A, and the second spacer 4b is disposed on the other end face C2. Each spacer 4 is disposed so as to connect to a portion of the external electrode 3 disposed on the second main surface A2. When the mounting surface of the capacitor body 1A is the first side face B1, the first spacer 4a is disposed on one end face C1 in the longitudinal direction L of the first side face B1, which is the mounting surface of the capacitor body 1A, and the second spacer 4b is disposed on the other end face C2.

[0030] In the following, the two surfaces of each spacer 4 facing in the stacking direction T will be referred to as the spacer main surfaces SA, the two surfaces facing in the length direction L as the spacer end surfaces SC, and the two surfaces facing in the width direction W as the spacer side surfaces SB.

[0031] Furthermore, of the two spacer end faces SC, the spacer end face SC closer to the center of the longitudinal direction L of the capacitor body 1A will be described as the central spacer end face SC1, and the spacer end face SC on the outside of the longitudinal direction L of the laminate 2 will be described as the outer spacer end face SC2.

[0032] Of the two spacer main surfaces SA, the spacer main surface SA on the capacitor body 1A side will be referred to as the body-side spacer main surface SA1, and the spacer main surface SA on the other side will be referred to as the mounting-side spacer main surface SA2. When the substrate mounting surface of the capacitor body 1A is the first side surface B1, of the two spacer side surfaces SB, the spacer side surface SB on the capacitor body 1A side will be referred to as the body-side spacer side surface SB1, and the spacer side surface SB on the other side will be referred to as the mounting-side spacer main surface SB2.

[0033] In the embodiment, the length in the longitudinal direction L of each spacer 4 is longer than the external electrode 3 arranged on the second main surface A2. That is, the center-side spacer end face SC1 of each spacer 4 extends beyond the external electrode 3, and there is a portion where the body-side spacer main surface SA1 of the spacer 4 is in direct contact with the second main surface A2 of the laminate 2. However, this is not limited thereto, and the length in the longitudinal direction L of each spacer 4 may be shorter than the external electrode arranged on the second main surface A2. The same applies when the substrate mounting surface of the capacitor body 1A is the first side surface B1.

[0034] In the embodiment, the external electrode 3 is configured by the base electrode layer 30 and the plating layer 31 covering it, and the spacer 4 is disposed on the surface of the plating layer 31. However, for example, the spacer 4 may be disposed on the surface of the base electrode layer 30, and a second plating layer may be disposed so as to cover the spacer 4 and the base electrode layer 30. By disposing the second plating layer, the adhesive strength between the spacer 4 and the base electrode layer 30 is improved.

[0035] (Material of Spacer 4) The spacer 4 contains either copper (Cu) or nickel (Ni) as metal powder and tin (Sn) as metal. The copper (Cu) and nickel (Ni) may be coated with silver (Ag). Furthermore, the spacer 4 may further contain silver (Ag) as a metal constituting an intermetallic compound.

[0036] Intermetallic compounds formed by adding tin (Sn) to either copper (Cu) or nickel (Ni) have a melting point that does not melt, even when soldering is performed when mounting the multilayer ceramic capacitor 1 on a wiring board, and do not deform due to heat. Therefore, the shape of the spacer 4 can be reliably maintained, and it is possible to arrange it while maintaining the desired shape even during soldering. In particular, intermetallic compounds formed by adding tin (Sn) to an alloy of copper (Cu) and nickel (Ni) are preferred as components for forming the spacer 4.

[0037] A phenolic resin may be contained in the metal region MP formed by the metal powder. The phenolic resin coats the particles of the intermetallic compound and is scattered so as to fill the gaps between the particles. The phenolic resin may not completely coat the particles of the intermetallic compound. Furthermore, by using a phenolic resin, the amount of gas generated during the heat treatment for forming the spacer 4 can be reduced, thereby reducing voids within the spacer 4. The phenolic resin may be exposed to the surface of the spacer 4 and coat at least a portion of the surface of the spacer 4. By coating the surface of the spacer 4 with the phenolic resin, the smoothness of the surface of the spacer 4 can be improved, and the mechanical strength of the spacer 4 can be increased.

[0038] Examples of the phenol resin include novolac-type phenol resins such as phenol novolac resin, phenol aralkyl resin, cresol novolac resin, Tcrt-butylphenol novolac resin, and nonylphenol novolac resin; resol-type phenol resin; and polyoxystyrene such as polyparaoxystyrene.

[0039] Fig. 4 is an enlarged view of the spacer 4 portion in the cross-sectional view of the multilayer ceramic capacitor 1 in Fig. 2. As shown in Fig. 4, metal powder MF may be contained in the resin region RP formed by the phenolic resin. The metal powder MF inhibits the shrinkage of the phenolic resin, thereby alleviating the shrinkage stress caused by the phenolic resin.

[0040] The spacer 4 preferably has a porosity of 20% or less in a region Z extending from the interface with the external electrode 3 to a depth of 5 μm. By keeping the porosity low, the bonding area of ​​the spacer 4 that is bonded to the external electrode 3 increases, improving the bonding strength with the external electrode 3.

[0041] A void P is formed inside the spacer 4, and the maximum diameter of the void P is preferably ½ or less of the maximum dimension of the thickness of the spacer 4 in the stacking direction T. If the diameter is greater than ½, cracks are more likely to occur starting from the void P, reducing the strength of the spacer 4. When the substrate mounting surface of the capacitor body 1A is the first side surface B1, the maximum diameter of the void P formed inside the spacer 4 is preferably ½ or less of the maximum dimension of the thickness of the spacer 4 in the width direction W.

[0042] Although the spacer material described above includes an intermetallic compound and a phenolic resin, the present invention is not limited to this and may include other metal components, or may include a resin other than phenolic resin, such as an epoxy resin or rosin, or a glass component. The spacer may also be formed without including resin. The spacer may be manufactured from a material containing copper or a copper alloy, and may be arranged to be connected via Ni plating and solder.

[0043] When the spacer 4 is smaller than the external electrode 3 in a plan view from the surface on which the spacer 4 is provided to the surface opposite to that surface, it is preferable to provide an orientation discriminator on at least a portion of the spacer 4. The orientation discriminator indicates the orientation for facing the second main surface A2 or the first side surface B1 on which the spacer 4 is provided to the wiring board when mounting the multilayer ceramic capacitor 1 on the wiring board. The orientation discriminator can be implemented by coloring the spacer 4 in a color different from the external electrode 3, printing an orientation identification mark for discriminating the orientation, such as a QR code (registered trademark), or providing a recess in a portion of the laminate. As a coloring method, a phenolic resin contained in the spacer 4 may be exposed on the surface of the spacer 4, so that the spacer 4 has a color different from that of the external electrode 3. The orientation discriminator may also be provided even when the spacer 4 is larger than the external electrode 3.

[0044] For example, if the spacers 4 and the external electrodes 3 have the same color, it may be difficult to tell which side the spacers 4 are attached to when viewed from above, which could lead to errors in image processing. However, providing a direction identification mark can prevent such errors in image processing.

[0045] (Protective Material 6) In this embodiment, the spacer 4 further includes a protective material 6 therein. The protective material 6 preferably includes resin, a water-repellent agent, ceramics, glass, or the like. The resin material may include an epoxy resin as the main component, combined with a phenolic resin curing agent, and a curing accelerator added thereto. In this case, the curing agent may be, for example, an acid anhydride-based, amine-based, or ester-based curing agent.

[0046] Furthermore, the protective material 6 has a stronger adhesive strength with, for example, the dielectric component contained in the laminate 2 than the intermetallic compound contained in the spacer 4. In this case, the adhesion between the laminate 2 and the spacer 4 can be made stronger by the bond between the protective material 6 and the laminate 2.

[0047] (Content of protective material 6 in the longitudinal direction L) As shown in Figure 4, the spacer 4 is divided into four parts L1, L2, L3, and L4 in the longitudinal direction L along a line extending in the stacking direction T, from the central spacer end face SC1 to the outer spacer end face SC2.

[0048] Here, when the area is divided into two parts, L1+L2 and L3+L4, it is preferable that the content of the protective material 6 is higher in the area L1+L2 closer to the center than in the area L3+L4 farther from the center.

[0049] Furthermore, when the region is divided into four parts, L1, L2, L3, and L4, it is preferable that the content of protective material 6 is highest in region L1 closest to the center, followed by region L2, which is second closest to the center, and it is even more preferable that the content of protective material 6 decreases from region L1 closest to the center to L2, L3, and L4 in that order.

[0050] (Content of protective material 6 in stacking direction T) The spacer 4 is divided into three parts T1, T2, and T3 along a line extending in the longitudinal direction L, in the stacking direction T, from the side closest to the capacitor body 1A, i.e., from the body-side spacer main surface SA1 toward the mounting-side spacer main surface SA2.

[0051] In this case, it is preferable that the content of the protective material 6 is higher in the region T1 closest to the capacitor body 1A than in the region T3 farthest from the capacitor body 1A. It is also preferable that the content of the metal component in the spacer 4 is highest in the region T3. If the content of the metal component in the region T3 on the side to be bonded with the solder is high, a strong bond between the solder and the spacer 4 is ensured.

[0052] (Content of protective material 6 in the longitudinal direction L and stacking direction T) The spacer 4 is divided into four parts in the longitudinal direction L: L1, L2, L3, and L4 from the central spacer end face SC1 toward the outer spacer end face SC2, and into three parts in the stacking direction T: T1, T2, and T3 from the body-side spacer main face SA1 toward the mounting-side spacer main face SA2 on the side closest to the capacitor body 1A, for a total of 12 parts.

[0053] In this case, it is preferable that the content of the protective material 6 is highest in the region LT11 where L1 and T1 are met, i.e., the region L1 closest to the center spacer end face SC1 and the region LT11 where T1 is met, which is the region closest to the capacitor body 1A. The content of the protective material 6 decreases toward the outer spacer end face SC2 and toward the mounting-side spacer main surface SA2, and it is preferable that the content of the protective material 6 is lowest in the region LT43 where L4 and T3 are met.

[0054] As described above, in the embodiment, each spacer 4 is longer than the length in the longitudinal direction L of the external electrode 3 arranged on the second main surface A2. That is, the body-side spacer main surface SA1 of the spacer 4 is in direct contact with the second main surface A2 of the laminate 2 that is not covered by the external electrode 3. The portion in direct contact is the region LT11 where the content of the protective material 6 is highest. Therefore, the spacer 4 is firmly bonded to the laminate 2 by bonding between the dielectric component of the laminate 2 and the protective material 6.

[0055] The content of the protective material 6 in the spacer 4 decreases toward the outer spacer end face SC2, resulting in a relative increase in the intermetallic compounds and metal components. The spacer 4 is in contact with the external electrode 3 on the outer spacer end face SC2 side, which increases the contact area between the intermetallic compounds and metal components of the spacer 4 and the external electrode 3, thereby ensuring good electrical connection between the spacer 4 and the external electrode 3 and increasing the bonding strength.

[0056] Furthermore, in the spacer 4, the content of the protective material 6 decreases and the metal component increases toward the mounting-side spacer main surface SA2, so that a strong bond between the solder and the spacer 4 is ensured.

[0057] 1, the reinforcing material 5 is disposed between the two spacers 4 so as to cover the second main surface side of the capacitor body 1A. In this case, the length in the longitudinal direction of the external electrodes disposed on the main surfaces may be approximately equal to the length in the longitudinal direction of the spacers, or the length in the longitudinal direction of the external electrodes may be longer.

[0058] (Material of Reinforcing Material 5) The main component of the reinforcing material 5 is preferably the same as the main component of the protective material 6. By using the same main component, the protective material 6 of the spacer 4 and the reinforcing material 5 are bonded together, improving the bonding strength between the spacer 4 and the protective material 6.

[0059] 2 , the reinforcing material 5 is disposed continuously in the length direction L between the central spacer end face SC1 of one spacer 4 and the central spacer end face SC1 of the other spacer 4, and covers the second main surface A2 of the capacitor body 1A (laminate 2) and each of the central spacer end faces SC1 of the two spacers 4. This provides more robust protection for the capacitor body 1A. When the substrate mounting surface of the capacitor body 1A is the first side face B1, the reinforcing material 5 covers the first side face B1 of the capacitor body 1A (laminate 2) and each of the central spacer end faces SC1 of the two spacers 4.

[0060] However, the reinforcing material 5 does not necessarily have to be continuous between the first spacer 4a and the second spacer 4b. For example, the reinforcing material 5 may be divided into two discontinuous sections: one covering the central spacer end face SC1 of the first spacer 4a and a portion on the second main surface A2 side of the capacitor body 1A (laminate 2) and the other covering the central spacer end face SC1 of the second spacer 4b and a portion on the second main surface A2 side of the capacitor body 1A (laminate 2). When the substrate mounting surface of the capacitor body 1A is the first side surface B1, the reinforcing material 5 may be divided into two discontinuous sections: one covering the central spacer end face SC1 of the first spacer 4a and a portion on the first side surface B1 side of the capacitor body 1A (laminate 2) and the other covering the central spacer end face SC1 of the second spacer 4b and a portion on the first side surface B1 side of the capacitor body 1A (laminate 2).

[0061] (Measuring Method) The content of the protective material 6 can be measured as follows: First, the spacer 4 is scraped off until the dimension in the width direction W is reduced to 1 / 2 so that the cross section of the spacer side surface SB can be seen.

[0062] A microscope (Axio (registered trademark) Imager-MAT, manufactured by ZEISS) is used to photograph the cross section of the spacer 4 at a total magnification of 100 to 500 times.

[0063] In the captured image, the spacer 4 is divided into three parts in the stacking direction T along lines extending in the length direction L in the thickest region of the spacer 4 in the stacking direction T, and into two to four parts in the length direction L along lines extending in the stacking direction T.

[0064] (Method of Manufacturing Multilayer Ceramic Capacitor 1) Fig. 5 is a flowchart illustrating a method of manufacturing the multilayer ceramic capacitor 1. The method of manufacturing the multilayer ceramic capacitor 1 includes a laminate manufacturing step S1, an external electrode forming step S2, a protective material and reinforcing material paste arranging step S3, a spacer paste arranging step S4, and a reflow step S5. Fig. 6 is a diagram illustrating the laminate manufacturing step S1 and the external electrode forming step S2. Fig. 7 is a diagram illustrating the protective material and reinforcing material paste arranging step S3, the spacer paste arranging step S4, and the reflow step S5.

[0065] (Laminate manufacturing process S1) A ceramic slurry containing ceramic powder, a binder, and a solvent is formed into a sheet on the surface of a carrier film using a die coater, gravure coater, microgravure coater, or the like to prepare a ceramic green sheet 101 for lamination that will become the dielectric layer 14. Next, a conductive paste is printed in strips on the ceramic green sheet 101 for lamination by screen printing, inkjet printing, gravure printing, or the like, and a conductive pattern 102 that will become the internal electrode layer 15 is printed on the surface of the ceramic green sheet 101 for lamination to prepare a material sheet 103.

[0066] 6( a), a plurality of material sheets 103 are stacked such that the conductive patterns 102 face the same direction and are offset, for example, by half a pitch, between adjacent material sheets 103 in the length direction L. Furthermore, outer layer ceramic green sheets 112 that will become the outer layer portions 12 are stacked on both sides of the plurality of stacked material sheets 103.

[0067] The stacked material sheets 103 and the outer layer ceramic green sheets 112 are pressed together by a hydrostatic press or the like to form a mother block 110 shown in FIG. 6(b).

[0068] Next, the mother block 110 is cut along cutting lines X and Y intersecting with cutting line X shown in FIG. 6(b) to produce a plurality of laminates 2 shown in FIG. 6(c).

[0069] (External electrode formation process S2) Next, a conductive paste containing copper (Cu) is applied to and baked on the end surface C of the laminate 2 to form a base electrode layer 30. The base electrode layer 30 is formed not only on both end surfaces C of the laminate 2, but also extends to the main surface A and side surface B of the laminate 2, covering a portion of the end surface C side of the main surface A. Next, a nickel (Ni) plating layer 31a and a tin (Sn) plating layer 31b disposed on the surface of the nickel (Ni) plating layer 31a are formed as plating layers 31 on the surface of the base electrode layer 30, thereby producing the capacitor body 1A shown in FIG. 6( d ). The configuration of the external electrodes is not limited to this.

[0070] (Reinforcing material paste placement process S3) In this embodiment, the protective material 6 and the reinforcing material are formed from the same material. In this case, the surface of the capacitor body 1A on which the spacer 4 is placed is first cleaned with a solvent, and then a reinforcing material paste 51 is applied between the two external electrodes 3, as shown in Figure 7(a).

[0071] 7(b), the spacer paste 41 is applied onto the external electrodes 3 of the capacitor body 1A in a state in which the reinforcing material paste 51 has been applied between the two external electrodes 3. At this time, the spacer paste 41 is applied so as to cover not only the external electrodes 3 but also part of the reinforcing material paste 51.

[0072] 7(c), the uncured reinforcing material paste 51 and the uncured spacer paste 41 are cured simultaneously by reflow. At this time, the reinforcing material penetrates into the area of ​​the spacer paste 41 close to the reinforcing material paste 51 as the protective material 6, thereby forming an area with a high content of the protective material 6. Furthermore, by increasing the amount of the reinforcing material paste 51 at this time, the content of the protective material 6 in the spacer 4 can be further increased.

[0073] (Modification) In a modification in which the protective material 6 and the reinforcing material 5 are formed from different materials, after the external electrode forming step S2, the steps are performed in the following order as shown in Figures 8 and 9. Figure 8 is a flowchart showing the protective material 6 and reinforcing material forming step in the modification, and Figure 9 is a diagram explaining the protective material 6 and reinforcing material forming step in the modification.

[0074] 9(a), a protective material paste 61, which is the material for the protective material 6, is applied by a dispenser or squeegee printing to the exposed portions of the laminate 2 between the external electrodes 3 of the capacitor body 1A. The protective material paste 61 is applied so as to contact the external electrodes 3 and not to cover more than 15% of the area of ​​the external electrodes 3.

[0075] (Spacer Paste Arranging Step S14) As shown in FIG. 9B, spacer paste 41 is applied onto the capacitor body 1A on which the protective material paste 61 has been applied.

[0076] 9(c), reflow is performed on the capacitor body 1A with the protective material paste 61 and the spacer paste 41 applied. The uncured protective material paste 61 and the spacer paste 41 are cured simultaneously by reflow, thereby forming a spacer 4 having a different content of protective material 6 depending on the position. Furthermore, the content of protective material 6 in the spacer 4 can be manipulated by changing the amount and position of application of the protective material 6.

[0077] (Reinforcing material paste placement process S16) As shown in Figure 9 (d), the surface of the capacitor body 1A on which the spacers 4 are placed is washed with a solvent, and reinforcing material paste 51 is placed between the two spacers 4 on the capacitor body 1A on which the spacers 4 are placed using a dispenser or squeegee printing.

[0078] (Second Reflow Process S17) Next, reflow is performed on the capacitor body 1A with the reinforcing material paste 51 disposed between the two spacers 4. The reflow hardens the unhardened reinforcing material paste 51. Through the above processes, the multilayer ceramic capacitor 1 of the embodiment is manufactured.

[0079] As described above, in the multilayer ceramic capacitor 1 of the embodiment, the spacer 4 is attached to the capacitor body 1A, and therefore the spacer 4 can buffer vibrations generated in the capacitor body 1A, thereby suppressing vibrations transmitted to the mounting board.

[0080] Furthermore, in the multilayer ceramic capacitor 1 of the embodiment, the reinforcing material 5 is attached between the spacers 4, which strengthens the adhesive force between the external electrodes 3 and the spacers 4 and prevents the spacers 4 from peeling off from the capacitor body 1A.

[0081] Each spacer 4 is longer in the longitudinal direction L than the portion of the external electrode 3 that covers the second main surface A2 side of the capacitor body 1A. The spacer 4 includes an intermetallic compound containing at least one of Cu and Ni as a high-melting-point metal and Sn as a low-melting-point metal, and a protective material. In addition, the protective material 6 has a stronger adhesive strength with, for example, the dielectric component contained in the laminate 2 than the intermetallic compound contained in the spacer 4. Furthermore, when the spacer 4 is divided into two in the longitudinal direction L, the region closer to the center of the capacitor body 1A in the longitudinal direction L has a higher content of protective material 6 than the region further away.

[0082] In this way, the content of the protective material 6 is high in the joint between the spacer 4 and the laminate 2. The adhesive force between the protective material 6 and the dielectric component of the laminate 2 is strong, so that a strong bond between the spacer 4 and the laminate 2 can be ensured.

[0083] Furthermore, the protective material content is low and the intermetallic compound content is high at the joint between the spacer 4 and the external electrode 3. Therefore, a strong bond between the spacer 4 and the external electrode 3 can be ensured by the metallic bond between the intermetallic compound of the spacer 4 and the external electrode 3.

[0084] Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments and can be embodied in various forms without departing from the spirit of the present invention. The present invention includes the following combinations.

[0085] <1> A capacitor body including: a laminate in which dielectric layers and internal electrode layers are alternately laminated, the laminate having two main surfaces opposing each other in a lamination direction, two end faces opposing each other in a length direction intersecting the lamination direction, and two side surfaces opposing each other in a width direction intersecting the lamination direction and the length direction; and two external electrodes disposed on the two end faces, respectively, connected to the internal electrode layers, and extending to the two main surfaces to cover parts of the main surfaces; and a capacitor body including a capacitor body on one main surface side of the capacitor body, the external electrode covering the part of the main surfaces. and two spacers sandwiched between the external electrodes and disposed on one end face side and the other end face side, each of the spacers being longer in the length direction than the external electrode covering one of the main surfaces, each spacer including an intermetallic compound containing at least one of Cu and Ni as a high-melting-point metal and Sn as a low-melting-point metal, and a protective material, wherein when the capacitor body is divided into two in the length direction along a line extending in the stacking direction, a region closer to a center of the capacitor body in the length direction has a higher content of the protective material than a region further away.

[0086] <2> A multilayer ceramic electronic component comprising: a capacitor body in which dielectric layers and internal electrode layers are alternately stacked, the capacitor body including: a laminate having two main surfaces opposing each other in a stacking direction, two end surfaces opposing each other in a length direction intersecting the stacking direction, and two side surfaces opposing each other in a width direction intersecting the stacking direction and the length direction; and two external electrodes disposed on the two end surfaces, respectively, to connect to the internal electrode layers and extend to the two main surfaces to cover parts of the main surfaces and the two side surfaces to cover parts of the side surfaces; and two spacers disposed on one end surface side and the other end surface side of the capacitor body, respectively, on one main surface side or one side surface side, with the external electrodes covering the part of the main surfaces or the part of the side surfaces sandwiched between them, the spacers including a metal component and a protective material, and when the capacitor body is divided into two in the length direction along a line extending in the stacking direction, a region closer to a center of the capacitor body in the length direction has a higher content of the protective material than a region further away, and a reinforcing material is disposed between the two external electrodes.

[0087] <3> The multilayer ceramic electronic component according to <1> or <2>, wherein the protective material contains a resin.

[0088] <4> The multilayer ceramic electronic component according to any one of <1> to <3>, wherein, when each of the spacers is divided into three in the stacking direction, the area closest to the capacitor body has a higher content of the protective material than the area farthest from the capacitor body.

[0089] <5> The multilayer ceramic electronic component according to <4>, wherein the content of the protective material in the three divided regions of the spacer decreases in order from the region closest to the capacitor body to the region furthest from the capacitor body.

[0090] <6> The multilayer ceramic electronic component according to any one of <1> to <5>, wherein, when each of the spacers is divided into four in the longitudinal direction, the area closest to the center of the capacitor body in the longitudinal direction has the highest content of the protective material, and the area second closest to the center of the capacitor body in the longitudinal direction has the second highest content of the protective material.

[0091] <7> The multilayer ceramic electronic component according to any one of <1> to <6>, wherein a reinforcing material is disposed between the two external electrodes, and the main component of the reinforcing material is the same as the main component of the protective material.

[0092] <8> The multilayer ceramic electronic component according to <7>, wherein the reinforcing material is disposed continuously in the length direction.

[0093] REFERENCE SIGNS LIST 1 Multilayer ceramic capacitor 1A Capacitor body 2 Laminate 3a First external electrode 3b Second external electrode 4 Spacer 4a First spacer 4b Second spacer 5 Reinforcing material 6 Protective material 11 Inner layer portion 12 Outer layer portion 14 Dielectric layer 15 Internal electrode layer 51 Reinforcing material paste 61 Protective material paste

Claims

1. A laminate having two main surfaces that face each other in a stacking direction, two end surfaces that face each other in a length direction that intersects the stacking direction, and two side surfaces that face each other in a width direction that intersects the stacking direction and the length direction; and a capacitor body including two external electrodes disposed on the two end faces, respectively, and extending to the two main faces to cover parts of the main faces and to the two side faces to cover parts of the side faces; two spacers disposed on one end face side and the other end face side of one main surface side of the capacitor body, with the external electrode covering the part of the main surface sandwiched therebetween; Each of the spacers is In the longitudinal direction, the external electrode is longer than the external electrode covering the one main surface, Contains a metal component and a protective material, When the capacitor body is divided into two in the longitudinal direction along a line extending in the stacking direction, a region closer to a center portion in the longitudinal direction of the capacitor body has a higher content of the protective material than a region further away from the center portion. Multilayer ceramic electronic components.

2. A laminate having two main surfaces that face each other in a stacking direction, two end surfaces that face each other in a length direction that intersects the stacking direction, and two side surfaces that face each other in a width direction that intersects the stacking direction and the length direction; and a capacitor body including two external electrodes disposed on the two end faces, respectively, and extending to the two main faces to cover parts of the main faces and to the two side faces to cover parts of the side faces; two spacers disposed on one end face side and the other end face side of one main surface side of the capacitor body, with the external electrode covering the part of the main surface sandwiched therebetween; Each of the spacers is Contains a metal component and a protective material, When the capacitor body is divided into two in the longitudinal direction along a line extending in the lamination direction, a region closer to a center portion in the longitudinal direction of the capacitor body has a higher content of the protective material than a region further away from the center portion, a reinforcing material is disposed between the two external electrodes; Multilayer ceramic electronic components.

3. The protective material includes a resin.

3. The multilayer ceramic electronic component according to claim 1 or 2.

4. Each of the spacers is When the capacitor is divided into three parts in the stacking direction, the area closest to the capacitor body has a higher content of the protective material than the area farthest from the capacitor body.

3. The multilayer ceramic electronic component according to claim 1 or 2.

5. The three divided regions of the spacer are: The content of the protective material decreases from the region closest to the capacitor body to the region farther away. The multilayer ceramic electronic component according to claim 4.

6. Each of the spacers is When divided into four in the length direction, the content of the protective material is highest in a region closest to the center of the capacitor body in the longitudinal direction, The content of the protective material in the region second closest to the center in the length direction is the second highest.

3. The multilayer ceramic electronic component according to claim 1 or 2.

7. A reinforcing material is disposed between the two external electrodes; The main component of the reinforcing material is the same as the main component of the protective material.

3. The multilayer ceramic electronic component according to claim 1 or 2.

8. The reinforcing material is disposed continuously in the longitudinal direction. The multilayer ceramic electronic component according to claim 7.

9. A laminate having two main surfaces that face each other in a stacking direction, two end surfaces that face each other in a length direction that intersects the stacking direction, and two side surfaces that face each other in a width direction that intersects the stacking direction and the length direction; and a capacitor body including two external electrodes disposed on the two end faces, respectively, and extending to the two main faces to cover parts of the main faces and to the two side faces to cover parts of the side faces; two spacers disposed on one end face side and the other end face side of one side face of the capacitor body, with the external electrode covering the part of the side face sandwiched therebetween; Each of the spacers is In the longitudinal direction, the external electrode is longer than the external electrode covering the one main surface, Contains a metal component and a protective material, When the capacitor body is divided into two in the longitudinal direction along a line extending in the stacking direction, a region closer to a center portion in the longitudinal direction of the capacitor body has a higher content of the protective material than a region further away from the center portion. Multilayer ceramic electronic components.

10. A laminate having two main surfaces facing each other in a stacking direction, two end surfaces facing each other in a length direction intersecting the stacking direction, and two side surfaces facing each other in a width direction intersecting the stacking direction and the length direction; and a capacitor body including two external electrodes disposed on the two end faces, respectively, and extending to the two main faces to cover parts of the main faces and to the two side faces to cover parts of the side faces; two spacers disposed on one end face side and the other end face side of one side face of the capacitor body, with the external electrode covering the part of the side face sandwiched therebetween; Each of the spacers is Contains a metal component and a protective material, When the capacitor body is divided into two in the longitudinal direction along a line extending in the lamination direction, a region closer to a center portion in the longitudinal direction of the capacitor body has a higher content of the protective material than a region further away from the center portion, a reinforcing material is disposed between the two external electrodes; Multilayer ceramic electronic components.