Multilayer Ceramic Capacitors

Abstract

To provide a multilayer ceramic capacitor that suppresses the occurrence of cracks and chips in a ceramic body due to impact and the disconnection of the electrical connection between internal and external electrodes.SOLUTION: A multilayer ceramic capacitor 100 includes a ceramic body 1 including a first main surface 1A and a second main surface 1B that have a plurality of ceramic layers 1a stacked in a T direction and a plurality of first and second internal electrodes 2 and 3, and that face each other in the height direction, a first end surface 1C and a second end surface 1D facing each other in an L direction, and a first side surface and a second side surface that face each other in a width direction perpendicular to the T direction and the L direction, and also includes a first external electrode 4 formed on the first end surface and a part of the first main surface, not formed on the second main surface and electrically connected to the first internal electrode, a second external electrode formed on the second end surface and a part of the first main surface, not formed on the second main surface and electrically connected to the second internal electrode, two or more penetrating members 6, 7 penetrating between the first main surface and the second main surface, and a reinforcing layer 8 formed on at least a portion of the second main surface and covering the penetrating member.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a multilayer ceramic capacitor, and more particularly to a multilayer ceramic capacitor including a penetrating member formed to penetrate a ceramic body and a reinforcing layer formed on the surface of the ceramic body. [Background technology]

[0002] Multilayer ceramic capacitors are widely used in electronic devices and electrical equipment. In a conventional multilayer ceramic capacitor, external electrodes are formed in a cap shape on both ends of a ceramic body. In other words, the external electrodes are not only formed on the end faces of the ceramic body, but also extend from the end faces to parts of both main surfaces (the mounting surface and the top surface) and parts of both side surfaces. These extended parts are sometimes called folded parts of the external electrodes.

[0003] Meanwhile, in recent years, electronic devices and electrical equipment have become smaller and lighter, and there is a demand for smaller and lighter electronic components, including multilayer ceramic capacitors. As a multilayer ceramic capacitor that meets this demand, a multilayer ceramic capacitor equipped with L-shaped external electrodes is known.

[0004] Patent Document 1 (WO2018 / 220901A1) discloses a multilayer ceramic capacitor (ceramic electronic component) equipped with L-shaped external electrodes. FIG 17 shows a multilayer ceramic capacitor 1000 disclosed in Patent Document 1.

[0005] The multilayer ceramic capacitor 1000 includes a ceramic body 101. Internal electrodes 102 and 103 are formed inside the ceramic body 101. The internal electrode 102 is extended to one end surface of the ceramic body 101, and the internal electrode 103 is extended to the other end surface of the ceramic body 101.

[0006] An external electrode 104 is formed at one end of the ceramic body 101, and an external electrode 105 is formed at the other end of the ceramic body 101. The internal electrode 102 is electrically connected to the external electrode 104, and the internal electrode 103 is electrically connected to the external electrode 105.

[0007] External electrode 104 is formed on one end face of ceramic body 101 and part of the main surface on the mounting side, but not on the main surface on the top side. Similarly, external electrode 105 is formed on the other end face of ceramic body 101 and part of the main surface on the mounting side, but not on the main surface on the top side. When multilayer ceramic capacitor 1000 is cut along a plane parallel to the side surfaces and the cross section is viewed, external electrodes 104, 105 are L-shaped. Therefore, external electrodes 104, 105 are called L-shaped external electrodes.

[0008] Multilayer ceramic capacitor 1000, which has external electrodes 104 and 105 that are L-shaped external electrodes, is made smaller in size by being made thinner (lower in height) because no external electrodes are formed on the main surface on the top side of ceramic body 101. In addition, the weight is reduced because part of the external electrodes is omitted. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] WO2018 / 220901A1 publication Summary of the Invention [Problem to be solved by the invention]

[0010] As mentioned above, there is a demand for smaller and lighter electronic components, including multilayer ceramic capacitors, and recently, ultra-thin multilayer ceramic capacitors with heights of 100 μm or less are beginning to be used.

[0011] On the other hand, electronic components including multilayer ceramic capacitors are generally mounted on substrates and the like by being picked up by a mounter equipped with a vacuum suction nozzle.

[0012] Under these circumstances, in a multilayer ceramic capacitor that is thinned and has L-shaped external electrodes, there is a risk that an impact when mounting the capacitor on a substrate or the like using a mounter will cause the ceramic body to crack or chip, degrading the IR (insulation resistance) or causing the electrical connection between the internal and external electrodes to come off (break), resulting in fluctuations in electrical characteristics. In other words, because the external electrodes are L-shaped rather than cap-shaped, the ceramic body cannot be adequately protected by the external electrodes, and there is a risk that an impact will cause the ceramic body to crack or chip, or cause the electrical connection between the internal and external electrodes to come off. [Means for solving the problem]

[0013] The present invention has been made to solve the above-mentioned problems of the related art, and as a means therefor, a multilayer ceramic capacitor according to one embodiment of the present invention comprises a ceramic body having a plurality of ceramic layers stacked in a height direction, a plurality of first internal electrodes, and a plurality of second internal electrodes, the ceramic body having a first main surface and a second main surface opposed to each other in the height direction, a first end surface and a second end surface opposed to each other in a length direction perpendicular to the height direction, and a first side surface and a second side surface opposed to each other in a width direction perpendicular to the height direction and the length direction, the ceramic element body comprising: a first external electrode electrically connected to a first internal electrode formed on at least a portion of the second end face and a portion of the first main surface, but not formed on the second main surface; a second external electrode electrically connected to a second internal electrode formed on at least a portion of the second end face and a portion of the first main surface, but not formed on the second main surface; at least two penetrating members formed to penetrate between the first and second main surfaces of the ceramic element body; and a reinforcing layer formed on at least a portion of the second main surface of the ceramic element body, covering the penetrating members exposed from the ceramic element body, wherein the penetrating members are: Insulating Made of resin or InsulatingThe at least one penetrating member is made of rubber, and is in contact with a first external electrode formed on the first main surface. A multilayer ceramic capacitor according to another embodiment of the present invention includes a ceramic body having a plurality of ceramic layers stacked in a height direction, a plurality of first internal electrodes, and a plurality of second internal electrodes, the ceramic body having a first main surface and a second main surface opposed to each other in the height direction, a first end surface and a second end surface opposed to each other in a length direction perpendicular to the height direction, and a first side surface and a second side surface opposed to each other in a width direction perpendicular to the height direction and the length direction, and a first internal electrode formed on at least a part of the first end surface and a part of the first main surface but not formed on the second main surface, the first internal electrode being electrically connected to the first main surface. the ceramic body has a height dimension of 100 μm or less, the ceramic body including a first external electrode formed on at least a portion of the second end face and a portion of the first main surface, the second external electrode being electrically connected to the second internal electrode, the second external electrode being formed on at least a portion of the second end face and a portion of the first main surface, and not formed on the second main surface, at least two penetrating members formed to penetrate between the first and second main surfaces of the ceramic body, and a reinforcing layer formed on at least a portion of the second main surface of the ceramic body and covering the penetrating members exposed from the ceramic body, the at least one penetrating member abutting against the first external electrode formed on the first main surface and the reinforcing layer, the material of the reinforcing layer being DLC, and the ceramic body having a height dimension of 100 μm or less. The penetrating member is made of insulating resin or insulating rubber. This shall be the case. Effect of the Invention

[0014] The multilayer ceramic capacitor according to one embodiment of the present invention is suppressed from cracking or chipping in the ceramic body and from losing electrical connection between the internal electrodes and the external electrodes due to impact. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view of a multilayer ceramic capacitor 100. [Diagram 2] 2 is a cross-sectional view of the multilayer ceramic capacitor 100, showing a portion XX indicated by a dashed dotted line arrow in FIG. [Diagram 3] FIG. 1 is an exploded perspective view of a multilayer ceramic capacitor 100. [Figure 4] FIG. 1 is an exploded perspective view of a multilayer ceramic capacitor 100. [Diagram 5] 5(A) and 5(B) are explanatory diagrams each showing an example of a mounting method for the multilayer ceramic capacitor 100. [Figure 6] 6(A) to 6(C) are explanatory views showing steps carried out in an example of a method for manufacturing the multilayer ceramic capacitor 100. [Figure 7] 7(D) to (F) are continuations of FIG. 6(C), and are explanatory views showing steps carried out in an example of a method for manufacturing the multilayer ceramic capacitor 100. In FIG. [Figure 8] 1 is a cross-sectional view of a multilayer ceramic capacitor 200. FIG. [Figure 9] FIG. 2 is an exploded perspective view of the multilayer ceramic capacitor 200. [Figure 10] 10(A) to 10(C) are explanatory views showing steps carried out in an example of a method for manufacturing the multilayer ceramic capacitor 200. [Figure 11] 11(D) to (F) are continuations of FIG. 10(C), and are explanatory views showing steps carried out in an example of a method for manufacturing the multilayer ceramic capacitor 200. [Figure 12] Fig. 12(A) is a planar perspective view of a multilayer ceramic capacitor 300. Fig. 12(B) is a cross-sectional view of the multilayer ceramic capacitor 300, showing a portion YY indicated by an alternate long and short dashed arrow in Fig. 12(A). Fig. 12(C) is a cross-sectional view of the multilayer ceramic capacitor 300, showing a portion ZZ indicated by an alternate long and short dashed arrow in Fig. 12(A). [Figure 13] Fig. 13(A) is a planar perspective view of a multilayer ceramic capacitor 400. Fig. 13(B) is a cross-sectional view of the multilayer ceramic capacitor 400, showing a portion YY indicated by an alternate long and short dashed arrow in Fig. 13(A). Fig. 13(C) is a cross-sectional view of the multilayer ceramic capacitor 400, showing a portion ZZ indicated by an alternate long and short dashed arrow in Fig. 13(A). [Figure 14] 1 is a cross-sectional view of a multilayer ceramic capacitor 500. FIG. [Figure 15] FIG. 2 is a cross-sectional view of a multilayer ceramic capacitor 600. [Figure 16] 2 is a cross-sectional view of a multilayer ceramic capacitor 700. FIG. [Figure 17] 1 is a cross-sectional view of a multilayer ceramic capacitor 1000 disclosed in Patent Document 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] Note that each embodiment is an illustrative example of an embodiment of the present invention, and the present invention is not limited to the contents of the embodiment. In addition, it is possible to combine the contents described in different embodiments and implement them, and the implementation contents in such cases are also included in the present invention. In addition, the drawings are intended to aid in understanding the specification, and may be drawn diagrammatically, and the dimensional ratios of the drawn components or between the components may not match the dimensional ratios of those components described in the specification. In addition, components described in the specification may be omitted in the drawings, or may be drawn with the number of components omitted.

[0018] [First embodiment] 1 to 4 each show a multilayer ceramic capacitor 100 according to the first embodiment. FIG. 1 is a perspective view of the multilayer ceramic capacitor 100. FIG. 2 is a cross-sectional view of the multilayer ceramic capacitor 100, showing a portion XX indicated by a dashed line arrow in FIG. 1. FIG. 3 is an exploded perspective view of the multilayer ceramic capacitor 100, showing a state in which a reinforcing layer 8, which will be described later, is removed from a ceramic body 1, which will be described later. FIG. 4 is also an exploded perspective view of the multilayer ceramic capacitor 100, showing a state in which a first external electrode 4 and a second external electrode 5, which will be described later, are removed from the ceramic body 1, and the ceramic body 1 is disassembled into a plurality of ceramic layers 1a, which will be described later. Each figure shows the height direction T, length direction L, and width direction W of the multilayer ceramic capacitor 100, and these directions may be referred to in the following description. In this embodiment, the direction in which the ceramic layers 1a are stacked is defined as the height direction T.

[0019] The multilayer ceramic capacitor 100 includes a ceramic body 1 in which multiple ceramic layers 1a are laminated. The ceramic body 1 has a rectangular parallelepiped shape and has a first main surface 1A and a second main surface 1B facing each other in a height direction T, a first end surface 1C and a second end surface 1D facing each other in a length direction L perpendicular to the height direction T, and a first side surface 1E and a second side surface 1F facing each other in a width direction W perpendicular to the height direction T and the length direction L. In the ceramic body 1, the first main surface 1A is a mounting surface, and the second main surface 1B is a top surface.

[0020] The ceramic body 1 (ceramic layer 1a) may be made of any material, for example, a dielectric ceramic containing BaTiO3 as a main component, although dielectric ceramics containing other materials as main components, such as CaTiO3, SrTiO3, or CaZrO3, may be used instead of BaTiO3.

[0021] The number of ceramic layers 1a is arbitrary. The thickness dimension of the ceramic layers 1a is also arbitrary, but is preferably, for example, about 0.3 μm or more and 3.0 μm or less. The dimensions of the ceramic body 1 are also arbitrary, but in this embodiment, the dimension in the height direction T is 100 μm, the dimension in the length direction L is 400 μm, and the dimension in the width direction W is 200 μm.

[0022] In the ceramic body 1, a first internal electrode 2 is formed between predetermined layers, and a second internal electrode 3 is formed between other predetermined layers. The first internal electrode 2 is extended to a first end face 1C of the ceramic body 1. The second internal electrode 3 is extended to a second end face 1D of the ceramic body 1.

[0023] Each of the first internal electrode 2 and the second internal electrode 3 is composed of two or more layers. The first internal electrodes 2 and the second internal electrodes 3 are usually arranged alternately in the height direction T. The thickness dimension of the first internal electrode 2 and the second internal electrode 3 is arbitrary, but is preferably, for example, about 0.1 μm or more and 2.0 μm or less.

[0024] The main component material of the first internal electrode 2 and the second internal electrode 3 may be any material, but in this embodiment, Ni is used. However, other metals such as Cu, Ag, Pd, and Au may be used instead of Ni. Furthermore, Ni, Cu, Ag, Pd, and Au may be alloyed with other metals.

[0025] A first external electrode 4 is formed on one end of the ceramic body 1. The first external electrode 4 is an L-shaped external electrode. That is, when the multilayer ceramic capacitor 100 is cut along a plane parallel to the first side face 1E and the second side face 1F and the cross section is viewed, the first external electrode 4 has an L-shape. Specifically, the first external electrode 4 is formed on the entire first end face 1C of the ceramic body 1, a part of the first main face 1A, a part of the first side face 1E, and a part of the second side face 1F, but is not formed on the second main face 1B. The first external electrode 4 formed on the first side face 1E and the second side face 1F may be omitted.

[0026] A second external electrode 5 is formed on the other end of the ceramic body 1. The second external electrode 5 is also an L-shaped external electrode. Specifically, the second external electrode 5 is formed on the entire second end face 1D of the ceramic body 1, part of the first main surface 1A, part of the first side surface 1E, and part of the second side surface 1F, but not on the second main surface 1B. The second external electrode 5 formed on the first side surface 1E and the second side surface 1F may be omitted.

[0027] The first external electrode 4 is electrically connected to the first internal electrode 2 at a first end face 1C of the ceramic body 1. The second external electrode 5 is electrically connected to the second internal electrode 3 at a second end face 1D of the ceramic body 1.

[0028] The structure, material of the main component, and method of formation of the first external electrode 4 and the second external electrode 5 are arbitrary, but in this embodiment, the first external electrode 4 and the second external electrode 5 are formed in a multi-layer structure with a first layer formed by baking a conductive paste, and a second layer, a third layer, and a fourth layer formed by plating. Specifically, the first layer formed by baking a conductive paste uses Ni as the main component. However, other metals such as Cu, Ag, Pd, and Au may be used instead of Ni. In addition, Ni, Cu, Ag, Pd, and Au may be alloyed with other metals. In addition, the second layer formed by plating uses Cu as the main component, the third layer uses Ni as the main component, and the fourth layer uses Sn as the main component. In the cross-sectional view of FIG. 3, in order to make it easier to see, the first external electrode 4 and the second external electrode 5 are not shown as multiple layers (first to fourth layers) but as a single layer.

[0029] The thickness dimension of the first external electrode 4 is arbitrary, but in this embodiment it is about 10 μm on the first main surface 1A and about 10 μm on the first end surface 1C of the ceramic body 1. Similarly, the thickness dimension of the second external electrode 5 is arbitrary, but in this embodiment it is about 10 μm on the first main surface 1A of the ceramic body 1 and about 10 μm on the second end surface 1D.

[0030] The multilayer ceramic capacitor 100 includes a first penetrating member 6 and a second penetrating member 7 formed to penetrate between the first main surface 1A and the second main surface 1B of the ceramic body 1. In this embodiment, the first penetrating member 6 and the second penetrating member 7 are made of metal. Therefore, the first penetrating member 6 and the second penetrating member 7 are electrically conductive.

[0031] The specific main component (metal) material of the first penetrating member 6 and the second penetrating member 7 is arbitrary, but Ni is used in this embodiment. However, other metals such as Cu, Ag, Pd, and Au may be used instead of Ni. Ni, Cu, Ag, Pd, and Au may also be alloyed with other metals. The first penetrating member 6 and the second penetrating member 7 may not be made of metal, but may be made of conductive resin, etc.

[0032] The first penetrating member 6 and the second penetrating member 7 are provided to minimize the effect on the ceramic body 1 even if an impact (stress) is applied to the ceramic body 1. That is, when an impact is applied from one direction, the first penetrating member 6 and the second penetrating member 7 have the function of minimizing the effect on the ceramic body 1 and then dissipating the impact in the opposite direction. Furthermore, when an impact is applied from both directions (up and down), the first penetrating member 6 and the second penetrating member 7 have the function of reducing, absorbing, and supporting the impact so as to minimize the effect on the ceramic body 1.

[0033] The first penetrating member 6 and the second penetrating member 7 may have any shape, but in this embodiment, they are cylindrical. The first penetrating member 6 and the second penetrating member 7 may be shaped like other columns, such as a square column or a pentagonal column, instead of being cylindrical. The dimensions of the first penetrating member 6 and the second penetrating member 7 may also be any size, but in this embodiment, the diameter is about 30 μm. The dimensions of the first penetrating member 6 and the second penetrating member 7 in the height direction T are the same as the dimensions of the ceramic body 1 in the height direction T.

[0034] The first penetrating member 6 is electrically connected to the first internal electrode 2 inside the ceramic body 1. The first penetrating member 6 is also electrically connected to the first external electrode 4 on the first main surface 1A of the ceramic body 1.

[0035] The second penetrating member 7 is electrically connected to the second internal electrode 3 inside the ceramic body 1. The second penetrating member 7 is also electrically connected to the second external electrode 5 on the first main surface 1A of the ceramic body 1.

[0036] A reinforcing layer 8 is formed on the second main surface 1B of the ceramic body 1. The reinforcing layer 8 is provided to improve the mechanical strength of the ceramic body 1. In other words, the reinforcing layer 8 is provided to absorb impacts (stresses) applied to the ceramic body 1.

[0037] The material of the reinforcing layer 8 is arbitrary, but in this embodiment, DLC (Diamond-Like Carbon) is used as the material. DLC has high hardness, high wear resistance, high corrosion resistance, etc. DLC also has sufficient electrical insulation. The dimensions of the reinforcing layer 8 are also arbitrary, but in this embodiment, the thickness is about 5 μm. This value is necessary and sufficient to improve the mechanical strength of the ceramic body 1.

[0038] The reinforcing layer 8 covers the first penetrating member 6 and the second penetrating member 7 exposed from the second main surface 1B of the ceramic body 1. In this embodiment, the reinforcing layer 8 is formed on the entire second main surface 1B of the ceramic body 1. However, it is sufficient that the reinforcing layer 8 covers at least the first penetrating member 6 and the second penetrating member 7 exposed from the second main surface 1B of the ceramic body 1.

[0039] As described above, the multilayer ceramic capacitor 100 employs L-shaped external electrodes for the first external electrode 4 and the second external electrode 5. The first purpose is to reduce the thickness (to reduce the height), but employing L-shaped external electrodes for the first external electrode 4 and the second external electrode 5 is also extremely preferable in terms of mitigating impacts applied to the ceramic body 1 from the second main surface 1B side. That is, if L-shaped external electrodes are employed for the first external electrode 4 and the second external electrode 5, the second main surface 1B of the ceramic body 1 is flat without external electrodes being formed thereon, and the reinforced layer 8 formed thereon is also flat. On the other hand, if the first external electrode 4 and the second external electrode 5 are cap-shaped with external electrodes also formed on the second main surface 1B of the ceramic body 1, the reinforced layer 8 formed thereon will not be flat, and steps will be generated. A flat reinforced layer 8 has a higher effect of mitigating (absorbing) impacts than a reinforced layer 8 with steps. The multilayer ceramic capacitor 100 employs L-shaped external electrodes for the first external electrode 4 and the second external electrode 5, and since the reinforcement layer 8 can be made flat, it has a higher impact mitigation effect than when cap-shaped external electrodes are used.

[0040] (An example of a method for mounting the multilayer ceramic capacitor 100) The multilayer ceramic capacitor 100 is mounted on a substrate or the like by the method shown in Fig. 5(A) and (B), for example. Fig. 5(A) and (B) are explanatory diagrams each showing an example of a method for mounting the multilayer ceramic capacitor 100. Note that Fig. 5(A) shows the mounted multilayer ceramic capacitor 100 viewed from the direction of the second side surface 1F of the ceramic body 1. Fig. 5(B) shows the mounted multilayer ceramic capacitor 100 viewed from the direction of the second main surface 1B of the ceramic body 1.

[0041] First, the multilayer ceramic capacitor 100 is sucked by a vacuum suction nozzle at the reinforcing layer 8 formed on the second main surface 1B of the ceramic body 1. The vacuum suction nozzle has a tube formed therein. When the multilayer ceramic capacitor 100 is sucked, the pressure inside the tube is made a vacuum or reduced to less than atmospheric pressure.

[0042] Next, the vacuum suction nozzle is moved so that the multilayer ceramic capacitor 100 that has been sucked by the vacuum suction nozzle is placed on the substrate.

[0043] Next, the pressure inside the tube of the vacuum suction nozzle is made equal to atmospheric pressure. As a result, the multilayer ceramic capacitor 100 is released from the vacuum suction nozzle. After this, the multilayer ceramic capacitor 100 is fixed to the electrodes of the substrate and electrically connected, for example, by reflow soldering. This completes the mounting of the multilayer ceramic capacitor 100 on the substrate or the like.

[0044] In the above process, when the multilayer ceramic capacitor 100 is placed on the substrate by the vacuum suction nozzle, a large impact is applied to the multilayer ceramic capacitor 100. More specifically, a large impact is applied to the multilayer ceramic capacitor 100 from both the vacuum suction nozzle and the substrate. In a conventional multilayer ceramic capacitor that is thin-layered and has L-shaped external electrodes, there is a risk that cracks or chips will occur in the ceramic body and that electrical connections between the internal electrodes and external electrodes will be disconnected.

[0045] In contrast, in the multilayer ceramic capacitor 100, this impact is absorbed by the reinforcing layer 8. Furthermore, in the multilayer ceramic capacitor 100, this impact is absorbed by the first penetrating member 6 and the second penetrating member 7. More precisely, the reinforcing layer 8, the first penetrating member 6, and the second penetrating member 7 absorb the effect of the impact on the ceramic body 1.

[0046] In order to enhance these effects, when adsorbing the multilayer ceramic capacitor 100 with a vacuum suction nozzle, it is preferable to abut the vacuum suction nozzle against the portions of the multilayer ceramic capacitor 100 where the first penetrating member 6 and the second penetrating member 7 are formed, as shown in Figures 5(A) and (B).

[0047] In the multilayer ceramic capacitor 100 of this embodiment, the impact that occurs when mounting the multilayer ceramic capacitor 100 on a substrate or the like is mitigated by the reinforcing layer 8, the first penetrating member 6, and the second penetrating member 7, thereby suppressing the occurrence of cracks or chips in the ceramic body 1 and suppressing the loss of electrical connection between the first internal electrode 2 and the first external electrode 4 and between the second internal electrode 3 and the second external electrode 5.

[0048] The multilayer ceramic capacitor 100 suppresses deterioration of IR (insulation resistance) caused by cracks or chips in the ceramic body 1. The multilayer ceramic capacitor 100 also suppresses fluctuations in electrical characteristics caused by loss (disconnection) of the electrical connection between the first internal electrode 2 and the first external electrode 4 and between the second internal electrode 3 and the second external electrode 5.

[0049] (One Example of a Manufacturing Method for the Multilayer Ceramic Capacitor 100) The multilayer ceramic capacitor 100 can be manufactured, for example, by the manufacturing method shown in FIGS. 6(A) to 7(F).

[0050] First, an unsintered ceramic body 11 shown in Fig. 6(A) is produced. The unsintered ceramic body 11 is made by laminating a plurality of ceramic green sheets 11a, a plurality of conductive pastes 12 for forming the first internal electrodes 2, and a plurality of conductive pastes 13 for forming the second internal electrodes 3, pressing them together, and integrating them.

[0051] Although not shown in the figure, first, a powder of dielectric ceramics, a binder resin, a solvent, etc. are prepared and then wet-mixed to prepare a ceramic slurry.

[0052] Next, the ceramic slurry is applied in sheet form onto a carrier film using a die coater, gravure coater, microgravure coater, or the like, and then dried to prepare a ceramic green sheet.

[0053] Next, the conductive pastes 12 and 13 prepared in advance are applied (for example, printed) in a desired pattern shape on the main surfaces of the predetermined ceramic green sheets to form the first internal electrode 2 and the second internal electrode 3. Note that the conductive paste is not applied to the ceramic green sheets that will become the outer layers. Note that the conductive paste may be, for example, a mixture of a solvent, a binder resin, a metal powder (for example, Ni powder), etc.

[0054] Next, the ceramic green sheets are stacked in a predetermined order and integrated by heating and pressing to produce the green ceramic body 11 shown in Fig. 6(A). Note that in a typical production line, in order to manufacture a large number of multilayer ceramic capacitors 100 with high productivity, mother ceramic green sheets are often prepared, conductive pastes 12 and 13 are applied thereto, and the mother ceramic green sheets are stacked, pressed, and integrated to produce the green ceramic body, which is then divided into individual pieces to produce the green ceramic bodies 11.

[0055] 6(B), through holes 14 for forming the first penetrating member 6 and through holes 15 for forming the second penetrating member 7 are formed between both main surfaces of the unsintered ceramic body 11. The through holes 14 and 15 are formed, for example, by irradiation with laser light.

[0056] Next, as shown in FIG. 6(C), through hole 14 is filled with a conductive paste 16 for forming a first penetrating member 6 that has been prepared in advance, and through hole 15 is filled with a conductive paste 17 for forming a second penetrating member 7 that has been prepared in advance.

[0057] As described above, when preparing a mother unsintered ceramic body and then dividing the mother unsintered ceramic body into individual pieces to prepare unsintered ceramic bodies 11, it is preferable to form through holes 14, 15, fill through hole 14 with conductive paste 16, fill through hole 15 with conductive paste 17, and then divide the mother unsintered ceramic body into individual pieces to prepare unsintered ceramic bodies 11.

[0058] Next, the unsintered ceramic body 11 is fired with a predetermined profile to complete the ceramic body 1 shown in Fig. 7(D). At this time, the ceramic green sheet 11a is fired to become the ceramic layer 1a, and the conductive pastes 12 and 13 applied to the main surface of the ceramic green sheet 11a are fired at the same time to become the first internal electrode 2 and the second internal electrode 3. In addition, the conductive paste 16 filled in the through hole 14 and the conductive paste 17 filled in the through hole 15 are also fired, with the conductive paste 16 becoming the first penetrating member 6 and the conductive paste 17 becoming the second penetrating member 7.

[0059] 7(E), a reinforcing layer 8 is formed on the second main surface 1B of the ceramic body 1. As described above, in this embodiment, DLC is used as the material for the reinforcing layer 8, and in this case, the reinforcing layer 8 is formed on the second main surface 1B of the ceramic body 1 by a method such as thermal CVD, plasma CVD, vacuum deposition, ion plating, sputtering, or laser ablation using, for example, aliphatic hydrocarbons, aromatic hydrocarbons, oxygen-containing hydrocarbons, or nitrogen-containing hydrocarbons as raw materials. However, the raw materials and formation method of the reinforcing layer 8 are not limited to these.

[0060] Next, as shown in Fig. 7(F), a first external electrode 4 and a second external electrode 5 are formed on the surface of the ceramic body 1. Specifically, a conductive paste is applied and baked to form a first layer. Subsequently, a second layer, a third layer, and a fourth layer are formed by plating.

[0061] Through the above steps, the multilayer ceramic capacitor 100 according to the first embodiment is completed.

[0062] [Second embodiment] 8 and 9 each show a multilayer ceramic capacitor 200 according to the second embodiment. Fig. 8 is a cross-sectional view of the multilayer ceramic capacitor 200. Fig. 9 is an exploded perspective view of the multilayer ceramic capacitor 200.

[0063] The multilayer ceramic capacitor 200 according to the second embodiment is obtained by modifying a part of the configuration of the multilayer ceramic capacitor 100 according to the first embodiment described above. Specifically, in the multilayer ceramic capacitor 100, the first penetrating member 6 and the second penetrating member 7 are columnar (cylindrical). In the multilayer ceramic capacitor 200, this is modified to make the first penetrating member 26 and the second penetrating member 27 tubular (cylindrical). That is, the first penetrating member 26 has a hollow tubular portion 26a therein. The second penetrating member 27 has a hollow tubular portion 27a therein. However, the inside of the tubular portions 26a and 27a may be filled with another material (such as the material of the reinforcing layer 28). In addition, the first penetrating member 26 and the second penetrating member 27 may be tubular, such as a square or pentagonal tubular shape, instead of a cylindrical shape.

[0064] The first and second penetrating members 26 and 27 may be made of any material, but, like the first and second penetrating members 6 and 7 of the multilayer ceramic capacitor 100, Ni is used.

[0065] In the multilayer ceramic capacitor 200, a reinforcing layer 28 is also formed on the second main surface 1B of the ceramic body 1, but a hole 28a is formed in a portion corresponding to the cylindrical portion 26a of the first penetrating member 26 exposed on the second main surface 1B of the ceramic body 1, and a hole 28b is formed in a portion corresponding to the cylindrical portion 27a of the second penetrating member 27. The holes 28a and 28b are formed due to a problem in manufacturing technology in the process of forming the reinforcing layer 28. As described above, the cylindrical portion 26a of the first penetrating member 26 and the cylindrical portion 27a of the second penetrating member 27 may be filled with the material of the reinforcing layer 28.

[0066] In the multilayer ceramic capacitor 100, the first penetrating member 6 and the second penetrating member 7 are solid columnar, and therefore, when an impact is applied, there is a risk of cracks occurring between the first penetrating member 6 and the ceramic body 1, or between the second penetrating member 7 and the ceramic body 1. In contrast, in the multilayer ceramic capacitor 200, the first penetrating member 26 and the second penetrating member 27 are cylindrical with internal cavities (cylindrical portions 26a and 27a), and therefore, cracks are suppressed from occurring between the first penetrating member 26 and the ceramic body 1, or between the second penetrating member 27 and the ceramic body 1.

[0067] (One Example of a Manufacturing Method for the Multilayer Ceramic Capacitor 200) The multilayer ceramic capacitor 200 can be manufactured, for example, by the manufacturing method shown in FIGS. 10(A) to 11(F).

[0068] First, an unsintered ceramic body 11 shown in FIG. 10(A) is prepared.

[0069] Next, as shown in FIG. 10(B), through holes 14 for forming first penetrating members 26 and through holes 15 for forming second penetrating members 27 are formed between the two main surfaces of the unsintered ceramic body 11.

[0070] Next, the green ceramic body 11 is fired according to a prescribed profile to complete the ceramic body 1 shown in FIG. 10(C).

[0071] 11(D), a first penetrating member 26 is formed inside through hole 14, and a second penetrating member 27 is formed inside through hole 15 by plating, vapor deposition, sputtering, or the like. The formed first penetrating member 26 has a hollow cylindrical portion 26a therein, and the formed second penetrating member 27 has a hollow cylindrical portion 27a therein.

[0072] 11(E), a reinforcing layer 28 is formed on the second main surface 1B of the ceramic body 1. The reinforcing layer 28 thus formed has holes 28a and 28b.

[0073] Finally, as shown in FIG. 11(F), the first external electrode 4 and the second external electrode 5 are formed on the surface of the ceramic body 1, thereby completing the multilayer ceramic capacitor 200 according to the second embodiment.

[0074] [Third embodiment] Figures 12(A) to 12(C) each show a multilayer ceramic capacitor 300 according to the third embodiment. Fig. 12(A) is a planar perspective view of the multilayer ceramic capacitor 300. Fig. 12(B) is a cross-sectional view of the multilayer ceramic capacitor 300, showing the YY portion indicated by the dashed-dotted arrow in Fig. 12(A). Fig. 12(C) is also a cross-sectional view of the multilayer ceramic capacitor 300, showing the ZZ portion indicated by the dashed-dotted arrow in Fig. 12(A).

[0075] The multilayer ceramic capacitor 300 according to the third embodiment is obtained by modifying a part of the configuration of the multilayer ceramic capacitor 100 according to the first embodiment described above. Specifically, in the multilayer ceramic capacitor 100, the first penetrating member 6 is electrically connected to the first internal electrode 2. In addition, in the multilayer ceramic capacitor 100, the second penetrating member 7 is electrically connected to the second internal electrode 3. In contrast, in the multilayer ceramic capacitor 300, the first penetrating member 36 is not electrically connected to the first internal electrode 2, and the second penetrating member 37 is not electrically connected to the second internal electrode 3. In the multilayer ceramic capacitor 300, the number of the first penetrating members 36 is increased to two and formed on both sides of the first internal electrode 2 in the width direction W, and the number of the second penetrating members 37 is increased to two and formed on both sides of the second internal electrode 3 in the width direction W.

[0076] In the multilayer ceramic capacitor 300, the first penetrating member 36 and the first internal electrode 2 are not used for electrical connection, and therefore may be replaced from metal to non-conductive materials such as resin or rubber. Of course, metal may be used. However, resin or rubber may be more effective at absorbing shock than metal.

[0077] In the multilayer ceramic capacitor 300, as in the multilayer ceramic capacitor 100 of the first embodiment, impacts are mitigated by the reinforcing layer 8, the first penetrating member 26, and the second penetrating member 27, thereby preventing the ceramic body 1 from cracking or chipping and preventing the electrical connection between the first internal electrode 2 and the first external electrode 4 and the electrical connection between the second internal electrode 3 and the second external electrode 5 from being disconnected.

[0078] Furthermore, in the multilayer ceramic capacitor 300, the number of first penetrating members 26 is increased to two, and the number of second penetrating members 27 is increased to two, improving the effect of absorbing shock.

[0079] [Fourth embodiment] Figures 13(A) to (C) each show a multilayer ceramic capacitor 400 according to the fourth embodiment. Fig. 13(A) is a planar perspective view of the multilayer ceramic capacitor 400. Fig. 13(B) is a cross-sectional view of the multilayer ceramic capacitor 400, showing the YY portion indicated by the dashed-dotted arrow in Fig. 13(A). Fig. 13(C) is also a cross-sectional view of the multilayer ceramic capacitor 400, showing the ZZ portion indicated by the dashed-dotted arrow in Fig. 13(A).

[0080] The multilayer ceramic capacitor 400 according to the fourth embodiment is obtained by further modifying the multilayer ceramic capacitor 300 according to the third embodiment described above. Specifically, while the first penetrating member 26 and the second penetrating member 27 are columnar (cylindrical) in the multilayer ceramic capacitor 300, the first penetrating member 46 and the second penetrating member 47 are tubular (cylindrical) in the multilayer ceramic capacitor 400. That is, the first penetrating member 46 has a hollow tubular portion 46a therein, and the second penetrating member 47 has a hollow tubular portion 47a therein. In the multilayer ceramic capacitor 400, holes 48a are formed in the reinforcing layer 48 in portions corresponding to the tubular portions 46a and 47a, respectively.

[0081] In the multilayer ceramic capacitor 400, the occurrence of cracks or chips in the ceramic body 1 due to an impact is suppressed, and the electrical connection between the first internal electrode 2 and the first external electrode 4 and the electrical connection between the second internal electrode 3 and the second external electrode 5 are suppressed from being disconnected.

[0082] [Fifth embodiment] 14 shows a multilayer ceramic capacitor 500 according to the fifth embodiment. Note that FIG.

[0083] The multilayer ceramic capacitor 500 according to the fifth embodiment is obtained by adding a further configuration to the multilayer ceramic capacitor 100 according to the first embodiment described above. Specifically, the multilayer ceramic capacitor 500 has a second reinforcing layer 58 formed on a portion of the first main surface of the ceramic body 1 where the first external electrode 4 and the second external electrode are not formed.

[0084] Compared to the multilayer ceramic capacitor 100, the multilayer ceramic capacitor 500 has an improved effect of suppressing the occurrence of cracks or chips in the ceramic body 1, and an improved effect of suppressing the disconnection of the electrical connection between the first internal electrode 2 and the first external electrode 4, and the electrical connection between the second internal electrode 3 and the second external electrode 5.

[0085] In the multilayer ceramic capacitor 500, the shapes of the first penetrating member 6 and the second penetrating member 7 may be changed from a columnar (cylindrical) shape to a tubular (cylindrical) shape, as in the multilayer ceramic capacitor 200 according to the second embodiment. In the multilayer ceramic capacitor 500, the first penetrating member 6 may not be electrically connected to the first internal electrode 2, and the second penetrating member 7 may not be electrically connected to the second internal electrode 3, as in the multilayer ceramic capacitor 300 according to the third embodiment.

[0086] [Sixth embodiment] 15 shows a multilayer ceramic capacitor 600 according to the sixth embodiment. Note that FIG.

[0087] The multilayer ceramic capacitor 600 according to the sixth embodiment is a modified version of the multilayer ceramic capacitor 500 according to the fifth embodiment. Specifically, in the multilayer ceramic capacitor 500, the second reinforcing layer 58 was formed in a portion of the first main surface of the ceramic body 1 where the first external electrode 4 and the second external electrode 5 were not formed. In the multilayer ceramic capacitor 600, this has been modified, and the second reinforcing layer 68 is formed on the entire first main surface 1A of the ceramic body 1 from above the first external electrode 4 and the second external electrode 5, including the portion where the first external electrode 4 and the second external electrode 5 are formed.

[0088] The multilayer ceramic capacitor 600 also has an improved effect of suppressing the occurrence of cracks or chips in the ceramic body 1, and an improved effect of suppressing the disconnection of the electrical connection between the first internal electrode 2 and the first external electrode 4, and the electrical connection between the second internal electrode 3 and the second external electrode 5, compared to the multilayer ceramic capacitor 100.

[0089] When mounting the multilayer ceramic capacitor 600 on a substrate or the like, for example, a solder fillet may be formed between the first external electrode 4 formed on the first end face 1C of the ceramic body 1 and the electrode of the substrate, and a solder fillet may be formed between the second external electrode 5 formed on the second end face 1D of the ceramic body 1 and the electrode of the substrate, thereby fixing the multilayer ceramic capacitor 600 to the substrate and establishing an electrical connection.

[0090] [Seventh embodiment] 16 shows a multilayer ceramic capacitor 700 in accordance with the seventh embodiment. Note that FIG.

[0091] The multilayer ceramic capacitor 600 according to the seventh embodiment is also a partial modification of the multilayer ceramic capacitor 500 according to the fifth embodiment described above. Specifically, in the multilayer ceramic capacitor 500, the second reinforcing layer 58 was formed in a portion of the first main surface of the ceramic body 1 where the first external electrode 4 and the second external electrode 5 were not formed. The multilayer ceramic capacitor 700 changes this by forming a second reinforcing layer 78 over the entire first main surface 1A of the ceramic body 1, and then forming the first external electrode 4 and the second external electrode 5 on the second reinforcing layer 78.

[0092] In the multilayer ceramic capacitor 700, the effect of suppressing the occurrence of cracks or chips in the ceramic body 1 and the effect of suppressing the disconnection of the electrical connection between the first internal electrode 2 and the first external electrode 4 and the electrical connection between the second internal electrode 3 and the second external electrode 5 are further improved compared to the multilayer ceramic capacitor 100.

[0093] The above has described the multilayer ceramic capacitors 100, 200, 300, 400, 500, 600, and 700 according to the first to seventh embodiments. However, the present invention is not limited to the above-described content, and various modifications can be made in accordance with the spirit of the invention.

[0094] For example, in the multilayer ceramic capacitor 100, the first penetrating member 6 and the second penetrating member 7 are cylindrical, but instead they may be rectangular, pentagonal or other columnar shapes. Also, in the multilayer ceramic capacitor 200, the first penetrating member 26 and the second penetrating member 27 are cylindrical, but instead they may be rectangular, pentagonal or other cylindrical shapes.

[0095] Furthermore, in the multilayer ceramic capacitor 200 or the like in which the first penetrating member 26 and the second penetrating member 27 include the cylindrical portions 26a, 27a, the insides thereof may be filled with another material (such as the material of the reinforcing layer 28).

[0096] In addition, in the multilayer ceramic capacitor 100, etc., the number of first penetrating members 6 and second penetrating members 7 is one each, and in the multilayer ceramic capacitor 300, etc., the number of first penetrating members 36 and first internal electrodes 2 is two each, but these numbers are arbitrary and both can be increased or decreased.

[0097] Furthermore, the material of the first penetrating members 6, 26, 36, 46 and the second penetrating members 7, 27, 37, 47 is not limited to metal. When electrical conduction is not required, non-conductive materials such as resin or rubber may be used.

[0098] In addition, the material of the reinforcing layers 8, 28, 48 and the second reinforcing layers 58, 68, 78 is arbitrary and is not limited to the exemplified DLC (Diamond-Like Carbon), and any material that can be expected to have the effect of absorbing shock can be used. For example, resin, rubber, etc. may be used.

[0099] A multilayer ceramic capacitor according to one embodiment of the present invention is as described in the section "Means for Solving the Problems."

[0100] In the multilayer ceramic capacitor, it is also preferable that at least one penetrating member is conductive and electrically connected to the first external electrode, and at least one other penetrating member is conductive and electrically connected to the second external electrode, in which case the penetrating member can be used as a path for electrical connection.

[0101] It is also preferable that the conductive penetrating member electrically connected to the first external electrode is electrically connected to the first internal electrode, and the conductive penetrating member electrically connected to the second external electrode is electrically connected to the second internal electrode, in which case the penetrating member can be used as a path for electrical connection.

[0102] It is also preferable that the penetrating member is made of resin or rubber. In other words, if the penetrating member is not the only and essential electrical connection path, the penetrating member may be non-conductive. If the penetrating member is made of resin or rubber, the effect of absorbing impact is improved.

[0103] It is also preferable that the first internal electrode and the first external electrode are electrically connected at a first end face of the ceramic body, and the second internal electrode and the second external electrode are electrically connected at a second end face of the ceramic body. In the present invention, in these portions, the electrical connection between the first internal electrode and the first external electrode and the electrical connection between the second internal electrode and the second external electrode are prevented from being disconnected (disconnected).

[0104] The penetrating member may, for example, be columnar, or may, for example, be cylindrical.

[0105] It is also preferable that the material of the reinforcing layer is DLC (Diamond-Like Carbon), which can prevent cracks and chips from occurring in the ceramic body and prevent electrical disconnection between the internal electrodes and the external electrodes.

[0106] The height dimension of the ceramic body can be, for example, 100 μm or less. The present invention is particularly useful when the ceramic body is made into an ultra-thin layer. The height dimension of the ceramic body may be even smaller than 100 μm.

[0107] It is also preferable that a second reinforcing layer is formed on the first main surface of the ceramic body. In this case, the effect of suppressing the occurrence of cracks or chips in the ceramic body and the effect of suppressing the disconnection of the electrical connection between the internal electrodes and the external electrodes are further improved. The second reinforcing layer can be formed, for example, on a portion of the first main surface of the ceramic body where neither the first external electrode nor the second external electrode is formed.

[0108] Alternatively, a second reinforcing layer may be formed over the entire first main surface of the ceramic body, and a part of the first external electrode and a part of the second external electrode may be formed on the second reinforcing layer. In this case, it is possible to improve the effect of suppressing cracks and chips in the ceramic body and the effect of suppressing disconnection of the electrical connection between the internal electrode and the external electrode without deteriorating the functions of the first external electrode and the second external electrode. [Explanation of symbols]

[0109] 1. Ceramic body 1A...No. 1 Main surface 1B...2nd Main surface 1C...1st end surface 1D...Second end surface 1E...1st side 1F...2nd side 2...1st internal electrode 3...Second internal electrode 4...1st external electrode 5...Second external electrode 6, 26, 36, 46...First penetrating member 7, 27, 37, 47...Second penetrating member 8, 28, 48...Reinforcement layer 58, 68, 78...Second reinforcement layer

Claims

1. a ceramic body including a plurality of ceramic layers stacked in a height direction, a plurality of first internal electrodes, and a plurality of second internal electrodes, the ceramic body having a first main surface and a second main surface opposed to each other in the height direction, a first end surface and a second end surface opposed to each other in a length direction perpendicular to the height direction, and a first side surface and a second side surface opposed to each other in a width direction perpendicular to the height direction and the length direction, a first external electrode formed on at least a portion of the first end face and a portion of the first main surface, but not formed on the second main surface, the first external electrode being electrically connected to the first internal electrode; a second external electrode formed on at least a portion of the second end face and a portion of the first main surface, but not formed on the second main surface, the second external electrode being electrically connected to the second internal electrode; at least two penetrating members formed to penetrate between the first main surface and the second main surface of the ceramic body; a reinforcing layer formed on at least a part of the second main surface of the ceramic body and covering the penetrating member exposed from the ceramic body, The penetrating member is made of insulating resin or insulating rubber, At least one of the through members is in contact with the first external electrode formed on the first main surface. Multilayer ceramic capacitor.

2. a ceramic body including a plurality of ceramic layers stacked in a height direction, a plurality of first internal electrodes, and a plurality of second internal electrodes, the ceramic body having a first main surface and a second main surface opposed to each other in the height direction, a first end surface and a second end surface opposed to each other in a length direction perpendicular to the height direction, and a first side surface and a second side surface opposed to each other in a width direction perpendicular to the height direction and the length direction, a first external electrode formed on at least a portion of the first end face and a portion of the first main surface, but not formed on the second main surface, the first external electrode being electrically connected to the first internal electrode; a second external electrode formed on at least a portion of the second end face and a portion of the first main surface, but not formed on the second main surface, the second external electrode being electrically connected to the second internal electrode; at least two penetrating members formed to penetrate between the first main surface and the second main surface of the ceramic body; a reinforcing layer formed on at least a part of the second main surface of the ceramic body and covering the penetrating member exposed from the ceramic body, At least one of the through members abuts against the first external electrode formed on the first main surface and the reinforcing layer, The material of the reinforcing layer is DLC, The height dimension of the ceramic body is 100 μm or less, The penetrating member is made of insulating resin or insulating rubber. Multilayer ceramic capacitor.

3. the first internal electrode and the first external electrode are electrically connected to each other at the first end surface of the ceramic body; the second internal electrode and the second external electrode are electrically connected to each other at the second end surface of the ceramic body.

3. A multilayer ceramic capacitor according to claim 1 or 2.

4. The penetrating member is columnar.

4. A multilayer ceramic capacitor according to claim 1.

5. The penetrating member is cylindrical.

4. A multilayer ceramic capacitor according to claim 1.

6. A second reinforcing layer is formed on the first main surface of the ceramic body.

6. A multilayer ceramic capacitor according to claim 1.

7. the second reinforcing layer is formed on a portion of the first main surface of the ceramic body where neither the first external electrode nor the second external electrode is formed.

7. A multilayer ceramic capacitor according to claim 6.

8. the second reinforcing layer is formed on the entire first main surface of the ceramic body, A portion of the first external electrode and a portion of the second external electrode are each formed on the second reinforcing layer.

8. The multilayer ceramic capacitor according to claim 7.

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