Laminated ceramic electronic component

Abstract

Provided is a laminated ceramic capacitor having high fixing strength between an external electrode and a spacer and excellent durability when mounted. This laminated ceramic electronic component 1 is provided with: a capacitor body 1A comprising a laminate 2, in which dielectric layers 14 and internal electrode layers 15 are alternately laminated, and two external electrodes 3 that are respectively disposed on two end surfaces, are connected to the internal electrode layers 15, and cover a portion of a main surface and a portion of a side surface; two spacers 44 that are respectively disposed on one end surface side and the other end surface side, with the external electrode 3 covering the portion of the main surface or the portion of the side surface being sandwiched therebetween, at one main surface side or one side surface side of the capacitor body 1A; and a reinforcing material 5 disposed between the two spacers 4, wherein the reinforcing material 5 covers 50% or more of a center-side spacer end surface, where the two spacers 4 face each other, of two spacer end surfaces facing each other in a length direction in each of the two spacers 4.

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 achieve the above object, the present invention provides a multilayer ceramic electronic component comprising: a capacitor body including: a laminate in which dielectric layers and internal electrode layers are alternately stacked; 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 to extend to the two main surfaces and to cover parts of the main surfaces and the two side surfaces and to cover parts of the side surfaces; two spacers disposed on one end surface side and the other end surface side of one main surface side or one side surface side of the capacitor body, respectively, with the external electrodes sandwiched between them, the external electrodes covering the parts of the main surfaces or the parts of the side surfaces; and a reinforcing material disposed between the two spacers, wherein the reinforcing material covers 50% or more of a central spacer end surface facing each other between the two spacers, of two spacer end surfaces opposing each other in the length direction.

[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 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 spacer arranging step S3. FIG. 8 is a diagram illustrating a reinforcing material arranging step S4.

[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 comprises 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 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 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.

[0034] (Material of Spacer 4) The spacer 4 contains either copper (Cu) or nickel (Ni) and tin (Sn) as metal powder. 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] The area ratio of the phenolic resin in the spacer 4 is preferably 1% to 20% and particularly preferably 5% to 15% in the LT cross section perpendicular to the width direction W of the spacer 4. If it is less than 1%, the effect of the phenolic resin cannot be fully exerted, and if it exceeds 20%, the adhesive strength of the spacer to the external electrode may decrease.

[0039] The percentage (%) of the area occupied by the phenolic resin in the spacer 4 can be calculated, for example, by polishing the spacer 4 in the width direction W up to the center of the width direction W, and then photographing the polished surface with a microscope (BX-51) at a total magnification of 50x using a digital camera for microscopes (DP22 manufactured by Olympus). The obtained photographed image is binarized to separate it into metal regions MP and resin regions RP, and the percentage (%) of the area occupied by the phenolic resin can be calculated from the areas of the metal regions MP, metal powder MF, resin regions RP, and voids P using the formula: (area of ​​resin regions RP) / (area of ​​metal regions MP + area of ​​metal powder MF + area of ​​resin regions RP + area of ​​voids P) × 100.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] The porosity (%) can be calculated, for example, by polishing the spacer 4 in the width direction W up to the center of the width direction W, and then photographing the polished surface with a microscope (BX-51) at a total magnification of 50 times and a digital camera for microscopes (DP22 manufactured by Olympus). The obtained photographed image is binarized to separate it into metal regions MP and voids P, and the porosity (%) can be calculated from the areas of the metal regions MP, metal powder MF, resin regions RP, and voids P using the formula: (area of ​​voids P) / (area of ​​metal regions MP + area of ​​metal powder MF + area of ​​resin regions RP + area of ​​voids P) × 100.

[0044] 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.

[0045] When the spacer 4 is smaller than the external electrodes 3 in a plan view from the surface on which the spacer 4 is provided to the surface opposite the 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 electrodes 3, printing an orientation discriminator 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 electrodes 3. The orientation discriminator may also be provided on the laminate 2, not just the spacer 4. The orientation discriminator may also be provided even when the spacer 4 is larger than the external electrodes 3.

[0046] 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.

[0047] 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. When the substrate mounting surface of the capacitor body 1A is the first side surface B1, the reinforcing material 5 is disposed between the two spacers 4 so as to cover the first side surface side of the capacitor body 1A.

[0048] (Material of Reinforcing Material 5) The reinforcing material 5 includes an insulating resin, and in this embodiment, the reinforcing material 5 is mainly made of an insulating resin. The surface of the insulating resin may be coated with a water-repellent agent. Forming the reinforcing material 5 with an insulating resin improves flexural strength, and further coating it with a water-repellent agent improves moisture resistance. The insulating resin may contain ceramics, glass, etc. Furthermore, it is preferable that the reinforcing material 5 has a stronger adhesive strength with the laminate 2 than an intermetallic compound. For example, the reinforcing material 5 may be primarily composed of an epoxy resin, which may be combined with a phenolic resin as a curing agent. Other curing agents that can be used include acid anhydride-based, amine-based, and ester-based curing agents. A curing accelerator may also be added to the epoxy resin. The reinforcing material 5 may be formed solely from a water-repellent agent.

[0049] 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. 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.

[0050] 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).

[0051] 3, in this embodiment, when the area of ​​the center spacer end face SC1 of each spacer 4 (the region surrounded by a thick line in FIG. 3) is X0 and the area of ​​the reinforcing material 5 at the center spacer end face SC1 (the region shown by the shaded area in FIG. 3) is X1, X1 is preferably 50% or more of X0. In other words, it is preferable that the reinforcing material 5 covers 50% or more of the area of ​​the center spacer end face SC1 of each spacer 4.

[0052] In this way, since the reinforcing material 5 is fixed to the spacer 4 over 50% or more of the area of ​​the central spacer end face SC1, the reinforcing material 5 can be fixed to the spacer 4 with a strong force.

[0053] 2 and 3 , in the embodiment, the length (thickness) Tc of the reinforcing material 5 in the stacking direction T at the portion connected to the spacer 4 is preferably greater than the length (thickness) Tm of the reinforcing material 5 in the stacking direction T at approximately the center in the length direction L between two spacers 4, with Tm<Tc. If Tm<Tc, when viewed from one side in the width direction W, the reinforcing material 5 may have an arch shape whose thickness smoothly decreases from the portion with thickness Tc connected to the spacer 4 to the portion with thickness Tm at the center. Furthermore, the reinforcing material 5 may have a U-shaped cross section whose thickness suddenly changes from the portion with thickness Tc connected to the spacer 4 to the portion with thickness Tm at the center. In this way, by having the center portion of the reinforcing material 5 in the length direction recessed so that Tm<Tc, the possibility of contact between the substrate and the reinforcing material 5 is reduced even when the substrate is distorted.

[0054] 2 and 4 , in the embodiment, when viewed in a cross section passing through the longitudinal direction L and the stacking direction T, the spacers 4 do not protrude from the external electrodes 3 toward the center in the longitudinal direction L. In other words, the entire area of ​​the second main surface A2 of the laminate 2 that is exposed in the capacitor body 1A is covered with the reinforcing material 5. This makes it possible to maximize the bonding strength between the reinforcing material 5 and the laminate 2.

[0055] Unlike the embodiment, when viewed on a plane passing through the length direction L and the stacking direction T, the spacers 4 protrude from the external electrodes 3 toward the center in the length direction L, and if there is a gap between the spacers 4 and a portion of the second main surface A2 of the laminate 2 where the external electrodes 3 are not arranged, the reinforcing material 5 may be arranged so as to fill the gap. If the reinforcing material 5 fills the gap, the bonding area between the reinforcing material 5 and the spacers 4 increases, thereby increasing the bonding force. If the gap is not completely filled with the reinforcing material 5, the gap can mitigate the propagation of vibration.

[0056] Furthermore, the surface roughness Sa of the spacer 4 is preferably 0.3 μm or more. By making the surface roughness Sa of the spacer 4 0.3 μm or more, the anchor effect can be achieved to increase the adhesive strength between the spacer 4 and the reinforcing material 5. If the surface roughness is too large, the fillet formed by the reinforcing material 5 will not rise sufficiently, so the surface roughness is preferably 7.0 μm or less.

[0057] (Measurement Method) As described above, the measurement of the length (thickness) of the reinforcing material 5 in the lamination direction T can be performed, for example, as follows. When the wiring board and the multilayer ceramic capacitor 1 are joined by solder, the multilayer ceramic capacitor 1 joined to the wiring board by solder is polished in the width direction W to an LT cross section position where the multilayer ceramic capacitor 1 and the reinforcing material 5 can be seen. Next, using an Axio (registered trademark) Imager MAT, manufacturer: ZEIS, the length of the reinforcing material 5 in the lamination direction T is measured with an appropriate adjustment of the magnification, such as 100 to 500 times.

[0058] (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 spacer arranging step S3, and a reinforcing material arranging step S4. 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 spacer arranging step S3. Fig. 8 is a diagram illustrating the reinforcing material arranging step S4.

[0059] (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.

[0060] 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.

[0061] 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).

[0062] 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).

[0063] (External electrode forming process S2) Subsequently, a conductive paste containing copper (Cu) is applied to and baked on the end face C of the laminate 2 to form a base electrode layer 30. The base electrode layer 30 is formed not only on both end faces C of the laminate 2 but also extends to the main face A and side face B of the laminate 2, covering a portion of the end face C side of the main face 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.

[0064] (Spacer Arrangement Step S3) A spacer manufacturing paste 41 used for manufacturing spacers is prepared. The spacer manufacturing paste 41 contains metals made of copper (Cu), nickel (Ni), tin (Sn), and silver (Ag), a phenolic resin, a solvent, and an additive. In this case, rosin may be contained instead of the phenolic resin.

[0065] 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.

[0066] 7A and 7B are diagrams illustrating the spacer arranging step S3. As shown in Fig. 7A, first, a spacer manufacturing paste 41 is arranged on a holding substrate 40 by screen printing, dispensing, or the like.

[0067] 7(b), the capacitor body 1A is mounted on the upper surface of the holding substrate 40 with the second main surface A2 facing the holding substrate 40. At this time, the external electrodes 3 of the capacitor body 1A and the spacer-producing paste 41 are aligned, and the spacer-producing paste 41 adheres to the capacitor body 1A.

[0068] In this state, a heating step is carried out. When at least a portion of the metal in the paste generates an intermetallic compound to form the metal region MP, some of the phenolic resin is taken into the metal region MP and some is expelled from the metal region MP while hardening, forming the spacer 4 bonded to the capacitor body 1A.

[0069] 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 the phenolic resin, such as an epoxy resin or rosin, or a glass component. The spacer may also be formed without including a resin.

[0070] 7(c), the capacitor body 1A is separated from the holding substrate 40 together with the spacer 4. The manufacturing method is not limited to this, and the spacer may be formed by applying a spacer manufacturing paste in a desired shape directly on the surface of the capacitor body 1A and performing a heat treatment.

[0071] (Reinforcing Material Arrangement Step S4) Figure 8 is a diagram illustrating the reinforcing material arrangement step S4. First, the surface of the capacitor body 1A on which the spacers 4 are arranged is cleaned with a solvent. After cleaning is completed, as shown in Figure 8(a), the capacitor body 1A on which the spacers 4 are arranged is aligned so that the spacers 4 face upward.

[0072] 8(b), an insulating resin layer that will become the reinforcing material 5 is formed between the first spacer 4a and the second spacer 4b using a dispenser or squeegee printing on the capacitor body 1A on which the spacers 4 are arranged. The amount of insulating resin that wets onto the center spacer end surface SC1 can be changed by adjusting the amount of insulating resin.

[0073] When the insulating resin is to be allowed to penetrate into the interface between the spacer 4 and the laminate 2, the insulating resin can be placed and then evacuated. The amount of penetration can be controlled by changing the evacuation time and pressure. Through the above steps, the multilayer ceramic capacitor 1 of the embodiment is manufactured.

[0074] 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.

[0075] Furthermore, in the multilayer ceramic capacitor 1 of the embodiment, the reinforcing material 5 is attached between the spacers 4. This strengthens the adhesive strength between the capacitor body 1A and the spacers 4, preventing the spacers 4 from peeling off from the capacitor body 1A. Furthermore, resistance to cracks that may occur in the multilayer ceramic capacitor 1 when the mounting substrate is bent, i.e., substrate bending resistance, is improved.

[0076] Since the reinforcing material 5 covers 50% or more of the center spacer end surface SC1 of each of the two spacers 4, a high adhesive strength between the reinforcing material 5 and the spacers 4 can be ensured.

[0077] By forming the reinforcing material 5 from an insulating resin, the strength against bending can be improved, and further, by coating it with a water-repellent agent, the moisture resistance can be improved.

[0078] Since the surface roughness of the spacer 4 at the joint with the reinforcing material 5 is 0.3 μm or more, the anchor effect can increase the adhesive strength between the spacer 4 and the reinforcing material 5 .

[0079] The thickness Tc of the reinforcing material 5 in the stacking direction T at the central spacer end surface SC1 connected to the spacer 4 and the thickness Tm in the stacking direction T at the central portion in the length direction L between the two spacers 4 are such that Tm<Tc. Therefore, because the central portion in the length direction of the reinforcing material 5 is recessed, the possibility of contact between the mounting board and the reinforcing material 5 is reduced even when the multilayer ceramic capacitor 1 is warped.

[0080] When a gap is provided between the spacer 4 and the second main surface A2 of the laminate 2, it is preferable to place a reinforcing material 5 in the gap. In this case, the reinforcing material 5 enters the gap, increasing the bonding area between the reinforcing material 5 and the spacer 4 and strengthening the bonding force. On the other hand, when the gap is not completely filled with the reinforcing material 5, the gap can mitigate the propagation of vibration.

[0081] 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.

[0082] <1> A multilayer ceramic electronic component comprising: a capacitor body including: a laminate in which dielectric layers and internal electrode layers are alternately stacked; two main surfaces opposing each other in a stacking direction; two end faces opposing each other in a length direction intersecting the stacking direction; and two side surfaces opposing each other in a width direction intersecting both the stacking direction and the length direction; and two external electrodes disposed on the two end faces, respectively, to connect to the internal electrode layers and extend to the two main surfaces to cover portions of the main surfaces; 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 electrodes covering the portions of the main surfaces sandwiched therebetween; and a reinforcing material disposed between the two spacers, wherein the reinforcing material covers 50% or more of a center spacer end face facing each other between the two spacers, of the two spacer end faces opposing each other in the length direction.

[0083] <2> The multilayer ceramic electronic component according to <1>, wherein the reinforcing material includes an insulating resin.

[0084] <3> The multilayer ceramic electronic component according to <1> or <2>, wherein the reinforcing material is disposed continuously in the length direction.

[0085] <4> The multilayer ceramic electronic component according to any one of <1> to <3>, wherein the spacer has a surface roughness Sa of 0.3 μm or more at a joint portion where the spacer is joined to the reinforcing material.

[0086] <5> The multilayer ceramic electronic component according to any one of <1> to <4>, wherein a thickness Tm in the stacking direction of the reinforcing material 5 at the portion connected to the spacer is defined as a thickness Tc in the stacking direction at a central portion between two spacers in the length direction L, and wherein Tm<Tc.

[0087] <6> The multilayer ceramic electronic component according to any one of <1> to <5>, wherein a gap is provided between the spacer and the main surface of the laminate, and the reinforcing material is disposed in the gap.

[0088] REFERENCE SIGNS LIST 1 Multilayer ceramic capacitor 1A Capacitor body 2 Laminate 3 External electrode 3a First external electrode 3b Second external electrode 4 Spacer 4a First spacer 4b Second spacer 5 Reinforcement material 14 Dielectric layer 15 Internal electrode layer

Claims

1. a laminate in which dielectric layers and internal electrode layers are 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; a capacitor body including two external electrodes disposed on the two end faces, respectively, connected to the internal electrode layers, and extending to the two main faces to cover parts of the main faces and 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; a reinforcing member disposed between the two spacers; the reinforcing material covers 50% or more of a central spacer end face that faces each other between the two spacers, of the two spacer end faces that face each other in the length direction of each of the two spacers; Multilayer ceramic electronic components.

2. The reinforcing material includes an insulating resin. The multilayer ceramic electronic component according to claim 1 .

3. The reinforcing material is disposed continuously in the longitudinal direction. The multilayer ceramic electronic component according to claim 1 or 2.

4. The surface roughness Sa of the spacer at the joint with the reinforcing material is 0.3 μm or more. The multilayer ceramic electronic component according to claim 1 or 2.

5. The thickness Tm of the reinforcing material in the stacking direction at the portion connected to the spacer is When the thickness Tc between the two spacers at the center in the length direction L in the stacking direction is Tm<Tc, The multilayer ceramic electronic component according to claim 1 or 2.

6. a gap is provided between the spacer and the main surface of the laminate; The reinforcing material is disposed in the gap. The multilayer ceramic electronic component according to claim 1 or 2.

7. A laminate in which dielectric layers and internal electrode layers are stacked, and which has two main surfaces facing each other in the stacking direction, two end faces 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, connected to the internal electrode layers, and extending to the two main faces to cover parts of the main faces and 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; a reinforcing member disposed between the two spacers; the reinforcing material covers 50% or more of a center spacer end face that faces each other between the two spacers, of the two spacer end faces that face each other in the length direction of each of the two spacers; Multilayer ceramic electronic components.

8. The thickness Tm in the width direction of the reinforcing material at the portion connected to the spacer is When the thickness in the width direction at the center portion in the length direction L between the two spacers is Tc, Tm<Tc. The multilayer ceramic electronic component according to claim 7.