Electronic Components

Abstract

To provide an electronic component in which the occurrence of migration is suppressed even when an external electrode includes a conductive resin layer.SOLUTION: A multilayer capacitor C1 includes an element assembly 3, a plurality of external electrodes 5, and an electrically insulating film EI. The external electrodes 5 are disposed in the element assembly 3. The electrically insulating film EI is disposed in the element assembly 3. Each of the external electrodes 5 includes a second electrode layer E2. The electrically insulating film EI includes a film part existing at least on a region between the external electrodes 5 on a surface of the element assembly 3.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to electronic components. [Background technology]

[0002] A known electronic component includes an element body and a plurality of external electrodes disposed on the element body (see, for example, Patent Document 1). Each of the plurality of external electrodes includes a conductive resin layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-006501 Summary of the Invention [Problem to be solved by the invention]

[0004] The conductive resin layer generally contains a plurality of metal particles and a resin. In this case, migration may occur in the external electrodes. Migration is thought to occur, for example, due to the following events. The electric field acts on the metal particles contained in the conductive resin layer, ionizing the metal particles. The generated metal ions are attracted to the electric field generated between the external electrodes and migrate from the conductive resin layer. The electric field acting on the metal particles includes, for example, the electric field generated between the external electrodes, or the electric field generated between the external electrodes and the internal conductor disposed within the element body. The metal ions that migrate from the conductive resin layer react with electrons supplied from, for example, the element body or the external electrodes, and are deposited as metal on the surface of the element body.

[0005] An object of one aspect of the present invention is to provide an electronic component that suppresses the occurrence of migration even when external electrodes include a conductive resin layer. [Means for solving the problem]

[0006] An electronic component according to one aspect of the present invention comprises an element body, a plurality of external electrodes disposed on the element body, and an electrical insulating film disposed on the element body. Each of the plurality of external electrodes includes a conductive resin layer. The electrical insulating film includes film portions located at least on regions between the plurality of external electrodes on the surface of the element body.

[0007] In one aspect of the present invention, a film portion included in the electrical insulating film is located at least in the region between the plurality of external electrodes on the surface of the element body. Therefore, even if the metal particles included in the conductive resin layer ionize, the film portion inhibits the reaction between the generated metal ions and electrons supplied from the element body or the external electrodes. In other words, electrons are difficult to supply to the metal ions. As a result, the one aspect of the present invention suppresses the occurrence of migration.

[0008] The above-mentioned one aspect may include a plurality of internal electrodes. The plurality of internal electrodes may be arranged in the element body so as to face each other and may be electrically connected to corresponding external electrodes among the plurality of external electrodes. The element body may include a first side surface facing an outermost internal electrode among the plurality of internal electrodes, the outermost internal electrode being positioned in a direction in which the plurality of internal electrodes face each other. The conductive resin layer may include a portion located on the first side surface. The film portion may be located on the first side surface. In a configuration in which the conductive resin layer includes a portion located on the first side surface, there is a risk of ionization of metal particles contained in the conductive resin layer and in the portion located on the first side surface. However, in a configuration in which a film portion included in the electrical insulating film is located on the first side surface, the film portion reliably inhibits reaction between metal ions generated from metal particles contained in the conductive resin layer and in the portion located on the first side surface and electrons supplied from the element body or external electrode. As a result, a configuration in which a film portion included in the electrical insulating film is located on the first side surface reliably suppresses the occurrence of migration.

[0009] In the above-described one aspect, the element body may include a second side surface on which the plurality of internal electrodes extend in a direction facing each other. The conductive resin layer may include a portion located on the second side surface. The film portion may be located on the second side surface. In a configuration in which the conductive resin layer includes a portion located on the second side surface, there is a risk of ionization of metal particles contained in the conductive resin layer and in the portion located on the second side surface. However, in a configuration in which a film portion included in the electrical insulating film is located on the second side surface, the film portion reliably inhibits reaction between metal ions generated from metal particles contained in the conductive resin layer and in the portion located on the second side surface and electrons supplied from the element body or the external electrode. As a result, a configuration in which a film portion included in the electrical insulating film is located on the second side surface reliably suppresses the occurrence of migration.

[0010] In the above aspect, the element body may include an end surface at which a corresponding one of the plurality of internal electrodes is exposed, and the electrical insulating film may include a film portion located on the end surface. If the external electrodes include an electrolytic plating layer, there is a risk that the plating solution may penetrate into the element body. If the plating solution penetrates into the element body, the electrical characteristics of the electronic component may deteriorate. However, if the electrical insulating film includes a film portion located on the end face, the film portion located on the end face prevents the plating solution from penetrating into the element body, even if the external electrodes include an electrolytic plating layer. Therefore, a configuration in which the electrical insulating film includes a film portion located on the end face suppresses deterioration of the electrical characteristics of the electronic component.

[0011] In the above-described one aspect, each of the plurality of external electrodes may include a sintered metal layer formed on an electrically insulating film. The sintered metal layer may be physically and electrically connected to the corresponding internal electrode. The conductive resin layer may be formed on the sintered metal layer. In a configuration in which the sintered metal layer on which the conductive resin layer is formed is formed on the electrically insulating film, even when the metal particles contained in the conductive resin layer are ionized, it is more difficult for the metal ions to supply electrons, and therefore this configuration further suppresses the occurrence of migration.

[0012] In the above one aspect, the average thickness of the film portion located on the first side surface may be equal to or greater than the average thickness of the film portion located on the end surface. The structure in which the average thickness of the film portion located on the first side surface is equal to or greater than the average thickness of the film portion located on the end surface more reliably inhibits the reaction between metal ions generated from metal particles contained in the conductive resin layer and in the portion located on the first side surface and electrons supplied from the element body or the external electrode, and therefore more reliably suppresses the occurrence of migration. A configuration in which the electrical insulating film includes a film portion located on the end face may reduce the connectivity between the corresponding sintered metal layers and the internal electrodes. However, a configuration in which the average thickness of the film portion located on the end face is less than the average thickness of the film portion located on the first side face prevents the reduction in the connectivity between the corresponding sintered metal layers and the internal electrodes.

[0013] In the above one embodiment, the average thickness of the film portion located on the first side surface may be 0.05 μm or more. A configuration in which the average thickness of the film portion located on the first side surface is 0.05 μm or more reliably suppresses the occurrence of migration.

[0014] In the above one embodiment, the average thickness of the film portion located on the end face may be greater than 0 and not greater than 0.2 μm. A configuration in which the average thickness of the film portion located on the end face is greater than 0 and less than 0.2 μm reliably suppresses deterioration of the electrical characteristics of the electronic component and a decrease in the connectivity between corresponding sintered metal layers and internal electrodes.

[0015] In the above one embodiment, the distance between the outermost internal electrode and the first side surface may be 100 μm or more and 400 μm or less. In a configuration in which the distance between the outermost internal electrode and the first side surface is less than 100 μm, electrons tend to be supplied from the outermost internal electrode to the metal ions. Therefore, in a configuration in which the distance between the outermost internal electrode and the first side surface is 100 μm or more, electrons are less likely to be supplied from the outermost internal electrode to the metal ions. As a result, this configuration reliably suppresses the occurrence of migration. In a configuration in which the distance between the outermost internal electrode and the first side surface is greater than 400 μm, cracks tend to occur in the element body. Therefore, a configuration in which the distance between the outermost internal electrode and the first side surface is 400 μm or less suppresses cracks from occurring in the element body.

[0016] In the above-mentioned one aspect, the outermost internal electrode and the portion of the conductive resin layer located on the first side surface may not be electrically connected to each other, and the film portion located on the first side surface may be located between the outermost internal electrode and the portion of the conductive resin layer located on the first side surface. In a configuration in which the outermost internal electrode and the portion of the conductive resin layer located on the first side face are not electrically connected to each other, an electric field generated between the outermost internal electrode and the portion of the conductive resin layer located on the first side face acts on the metal particles contained in the conductive resin layer, easily ionizing the metal particles. However, in a configuration in which the film portion located on the first side face is located between the outermost internal electrode and the portion of the conductive resin layer located on the first side face, an electric field is unlikely to be generated between the outermost internal electrode and the portion of the conductive resin layer located on the first side face. Therefore, this configuration further suppresses the occurrence of migration.

[0017] In the above one aspect, each of the plurality of external electrodes may include a plating layer formed on the conductive resin layer so as to cover the conductive resin layer. In a configuration in which the conductive resin layer is covered with a plating layer, the plating layer suppresses the occurrence of migration even when the metal particles contained in the conductive resin layer are ionized. Therefore, this configuration further suppresses the occurrence of migration. In a configuration in which the conductive resin layer is covered with a plating layer, the plating layer suppresses peeling of the conductive resin layer.

[0018] In the above one embodiment, the electrical insulating film and the conductive resin layer may be in contact with each other. The structure in which the electrical insulating film and the conductive resin layer are in contact with each other reliably prevents electrons from being supplied to metal ions, and therefore reliably prevents migration.

[0019] In the above one aspect, the electrically insulating film may be made of an electrically insulating thin film.

[0020] In the above one aspect, the electrical insulating film may be made of a silicon oxide film. Silicon oxide films have high electrical insulation properties, so a configuration in which the electrical insulation film is made of silicon oxide films reliably suppresses the occurrence of migration.

[0021] In the above-described one aspect, the conductive resin layer may contain a plurality of silver particles. [Effects of the Invention]

[0022] One aspect of the present invention provides an electronic component that suppresses the occurrence of migration even when external electrodes include a conductive resin layer. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view of a multilayer capacitor in accordance with an embodiment. [Figure 2] FIG. 2 is a diagram showing a cross-sectional structure of the multilayer capacitor in accordance with this embodiment. [Figure 3] FIG. 3 is a diagram showing a cross-sectional structure of the multilayer capacitor in accordance with this embodiment. [Figure 4] FIG. 4 is a schematic diagram showing an external electrode, an electrical insulating film, and an internal electrode. [Figure 5] FIG. 5 is a schematic diagram showing an external electrode, an electrical insulating film, and an internal electrode. [Figure 6] FIG. 6 is a schematic diagram showing a cross-sectional structure of the multilayer capacitor. [Figure 7] FIG. 7 is a schematic diagram showing a cross-sectional structure of the multilayer capacitor. [Figure 8] FIG. 8 is a chart showing the occurrence of migration in each sample. [Figure 9] FIG. 9 is a diagram showing a cross-sectional structure of a multilayer capacitor according to a modified example of this embodiment. [Figure 10] FIG. 10 is a diagram showing a cross-sectional structure of a multilayer capacitor according to a modified example of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same elements or elements having the same functions will be denoted by the same reference numerals, and redundant description will be omitted.

[0025] The configuration of the multilayer capacitor C1 in accordance with this embodiment will be described with reference to Figs. 1 to 5. Fig. 1 is a perspective view of the multilayer capacitor in accordance with this embodiment. Figs. 2 and 3 are views showing the cross-sectional configuration of the multilayer capacitor in accordance with this embodiment. Figs. 4 and 5 are schematic views showing external electrodes, electrical insulating films, and internal electrodes. In this embodiment, the electronic component is, for example, the multilayer capacitor C1.

[0026] As shown in FIGS. 1 to 3, the multilayer capacitor C1 comprises a rectangular parallelepiped element body 3, a plurality of external electrodes 5, and an electrical insulating film EI. In this embodiment, the multilayer capacitor C1 comprises a pair of external electrodes 5. The pair of external electrodes 5 are arranged on the outer surfaces of the element body 3. The pair of external electrodes 5 are spaced apart from each other. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and ridges, and a rectangular parallelepiped shape with rounded corners and ridges.

[0027] The element body 3 has a pair of side surfaces 3a facing each other, a pair of side surfaces 3c facing each other, and a pair of end surfaces 3e facing each other. The pair of side surfaces 3a, the pair of side surfaces 3c, and the pair of end surfaces 3e have a rectangular shape. The direction in which the pair of side surfaces 3a face each other is a first direction D1. The direction in which the pair of side surfaces 3c face each other is a third direction D3. The direction in which the pair of end surfaces 3e face each other is a second direction D2. The multilayer capacitor C1 is solder-mounted to an electronic device. The electronic device includes, for example, a circuit board or an electronic component. In the multilayer capacitor C1, one side surface 3a faces the electronic device. The one side surface 3a is arranged to form a mounting surface. The one side surface 3a is the mounting surface. One of the pair of side surfaces 3c may be arranged to form a mounting surface. For example, when the side surface 3a forms a first side surface, the side surface 3c forms a second side surface.

[0028] The first direction D1 is a direction perpendicular to each side surface 3a and perpendicular to the third direction D3. The second direction D2 is a direction parallel to each side surface 3a and each side surface 3c and perpendicular to the first direction D1 and the third direction D3. The third direction D3 is a direction perpendicular to each side surface 3c, and the second direction D2 is a direction perpendicular to each end surface 3e. In this embodiment, the length of the element body 3 in the second direction D2 is greater than the length of the element body 3 in the first direction D1 and is also greater than the length of the element body 3 in the third direction D3. The second direction D2 is the longitudinal direction of the element body 3. The length of the element body 3 in the first direction D1 and the length of the element body 3 in the third direction D3 may be equal to each other. The length of the element body 3 in the first direction D1 and the length of the element body 3 in the third direction D3 may be different from each other.

[0029] The length of the element body 3 in the first direction D1 is the height of the element body 3. The length of the element body 3 in the third direction D3 is the width of the element body 3. The length of the element body 3 in the second direction D2 is the length of the element body 3. In this embodiment, the height of the element body 3 is 0.1 to 2.5 mm, the width of the element body 3 is 0.1 to 5.0 mm, and the length of the element body 3 is 0.2 to 5.7 mm. For example, the height of the element body 3 is 2.5 mm, the width of the element body 3 is 2.5 mm, and the length of the element body 3 is 3.2 mm.

[0030] The pair of side surfaces 3c extend in the first direction D1 to connect the pair of side surfaces 3a. The pair of side surfaces 3c also extend in the second direction D2. The pair of end surfaces 3e extend in the first direction D1 to connect the pair of side surfaces 3a. The pair of end surfaces 3e also extend in the third direction D3.

[0031] The element body 3 has four ridge lines 3g, four ridge lines 3i, and four ridge lines 3j. The ridge lines 3g are located between the end face 3e and the side face 3a. The ridge lines 3i are located between the end face 3e and the side face 3c. The ridge lines 3j are located between the side face 3a and the side face 3c. In this embodiment, the ridge lines 3g, 3i, and 3j are rounded so as to be curved. The element body 3 is subjected to so-called R-chamfering. The end face 3e and the side face 3a are indirectly adjacent to each other via the ridge lines 3g. The end face 3e and the side face 3c are indirectly adjacent to each other via the ridge lines 3i. The side face 3a and the side face 3c are indirectly adjacent to each other via the ridge lines 3j.

[0032] The element body 3 is configured by stacking multiple dielectric layers in a first direction D1. The element body 3 has multiple dielectric layers stacked one on top of the other. In the element body 3, the stacking direction of the multiple dielectric layers coincides with the first direction D1. Each dielectric layer is configured, for example, from a sintered ceramic green sheet containing a dielectric material. The dielectric material includes, for example, a BaTiO3-based, Ba(Ti,Zr)O3-based, or (Ba,Ca)TiO3-based dielectric ceramic. In the actual element body 3, the dielectric layers are integrated to the extent that the boundaries between the dielectric layers are not visible.

[0033] As shown in FIGS. 2 and 3, the electrical insulating film EI is disposed on the element body 3. The electrical insulating film EI is disposed directly on the element body 3. The electrical insulating film EI includes a plurality of film portions EIa, EIc, and EIe. In this embodiment, the electrical insulating film EI includes a pair of film portions EIa, a pair of film portions EIc, and a pair of film portions EIe. Each film portion EIa is disposed on a corresponding side surface 3a of the pair of side surfaces 3a. Each film portion EIa covers the corresponding side surface 3a and is in direct contact with the corresponding side surface 3a. Each film portion EIc is disposed on a corresponding side surface 3c of the pair of side surfaces 3c. Each film portion EIc covers the corresponding side surface 3c and is in direct contact with the corresponding side surface 3c. Each film portion EIe is disposed on a corresponding end surface 3e of the pair of end surfaces 3e. Each film portion EIe covers the corresponding end surface 3e and is in direct contact with the corresponding end surface 3e. The electrical insulating film EI includes a plurality of film portions respectively disposed on the ridge line portions 3g, 3i, and 3j. Film portion EIa and film portion EIc are connected by a film portion disposed on the ridge line portion 3j. Film portion EIa and film portion EIe are connected by a film portion disposed on the ridge line portion 3g. Film portion EIc and film portion EIe are connected by a film portion disposed on the ridge line portion 3i. In this embodiment, the electrical insulating film EI covers substantially the entire element body 3.

[0034] The electrical insulating film EI has, for example, an electrical resistivity higher than that of the element body 3. The electrical resistivity of the element body 3 includes the volume resistivity or surface resistivity of the element body 3. The electrical insulating film EI may have an electrical resistivity higher than both the volume resistivity and the surface resistivity of the element body 3. The electrical insulating film EI is made of, for example, an electrically insulating thin film. In this case, the electrical insulating film EI may be made of a sputtered film. The electrical insulating film EI is made of, for example, a silicon oxide film. The silicon oxide film is, for example, a silicon dioxide film. The electrical insulating film EI may be made of, for example, an aluminum oxide film.

[0035] As shown in FIGS. 2 and 3, the multilayer capacitor C1 includes a plurality of internal electrodes 7 and a plurality of internal electrodes 9. Each of the internal electrodes 7 and 9 is an internal conductor disposed within the element body 3. Each of the internal electrodes 7 and 9 is made of a conductive material typically used as an internal conductor for multilayer electronic components. The conductive material includes, for example, a base metal. The conductive material includes, for example, Ni or Cu. The internal electrodes 7 and 9 are configured as a sintered body of a conductive paste containing the conductive material. In this embodiment, the internal electrodes 7 and 9 are made of Ni. In FIG. 3, for the sake of explanation, the internal electrodes 7 and 9 are intentionally illustrated as being shifted from each other in the third direction D3.

[0036] The internal electrodes 7 and the internal electrodes 9 are arranged at different positions (layers) in the first direction D1. The internal electrodes 7 and the internal electrodes 9 are arranged alternately within the element body 3 so as to face each other at an interval in the first direction D1. The internal electrodes 7 and the internal electrodes 9 have mutually opposite polarities. One end of the internal electrodes 7, 9 is exposed at the corresponding end face 3e. The internal electrodes 7, 9 have one end exposed at the corresponding end face 3e. The multiple internal electrodes 7 and the multiple internal electrodes 9 are arranged alternately in the first direction D1. The multiple internal electrodes 7, 9 are arranged in the element body 3 so as to be aligned in the first direction D1. Each internal electrode 7, 9 is located in a plane substantially parallel to the side surface 3c. The internal electrodes 7 and 9 face each other in the first direction D1. The direction in which the internal electrodes 7 and 9 face each other (first direction D1) is perpendicular to the directions parallel to the side surface 3a (second direction D2 and third direction D3). The multiple internal electrodes 7 include one internal electrode 7A located outermost in the first direction D1. The internal electrode 7A faces one of the pair of side surfaces 3a in the first direction D1. The multiple internal electrodes 9 include one internal electrode 9A located outermost in the first direction D1. The internal electrode 9A faces the other of the pair of side surfaces 3a in the first direction D1. Each of the internal electrodes 7A, 9A is an outermost internal electrode.

[0037] The external electrodes 5 are arranged on the element body 3 as shown in Figures 1 to 3. In this embodiment, the external electrodes 5 are arranged on the electrical insulating film EI. That is, the external electrodes 5 are arranged directly on the electrical insulating film EI and indirectly on the element body 3. The external electrodes 5 are respectively arranged at both ends of the element body 3 in the second direction D2. Each external electrode 5 is arranged on the side of the corresponding end face 3e of the element body 3. In this embodiment, each external electrode 5 is arranged on a pair of side faces 3a, a pair of side faces 3c, and one end face 3e. As shown in Figures 2 and 3, the external electrode 5 has multiple electrode portions 5a, 5c, and 5e. The electrode portion 5a is arranged on the side face 3a and the ridge portion 3g. Each electrode portion 5c is arranged on the side face 3c and the ridge portion 3i. The electrode portion 5e is arranged on the end face 3e. The external electrode 5 also has an electrode portion arranged on the ridge portion 3j.

[0038] The external electrode 5 is formed on an electrical insulating film EI so as to cover five surfaces, including the pair of side surfaces 3a, one end surface 3e, and the pair of side surfaces 3c, as well as the ridges 3g, 3i, and 3j. Adjacent electrode portions 5a, 5c, and 5e are electrically connected. The electrode portion 5e covers one end of the corresponding internal electrode 7 or 9. The electrode portion 5e is directly connected to the corresponding internal electrode 7 or 9. The external electrode 5 is electrically connected to the corresponding internal electrode 7 or 9. As shown in FIGS. 2 and 3, the external electrode 5 includes a first electrode layer E1, a second electrode layer E2, and a third electrode layer E3. The third electrode layer E3 constitutes the outermost layer of the external electrode 5. Each of the electrode portions 5a, 5c, and 5e includes a first electrode layer E1, a second electrode layer E2, and a third electrode layer E3. Each of the electrode portions 5a, 5c, and 5e has a three-layer structure.

[0039] The first electrode layer E1 of the electrode portion 5a is disposed on the side surface 3a and the ridge portion 3g. The first electrode layer E1 of the electrode portion 5a is formed on the electrical insulating film EI so as to cover a portion of the side surface 3a and the entire ridge portion 3g. The first electrode layer E1 of the electrode portion 5a is in contact with the electrical insulating film EI on the portion of the side surface 3a and on the ridge portion 3g. That is, in the electrode portion 5a, the first electrode layer E1 is in direct contact with the electrical insulating film EI (film portion EIa). The portion of the side surface 3a is indirectly covered by the first electrode layer E1, and the remaining portion excluding the portion is exposed from the first electrode layer E1. The portion of the side surface 3a is a partial region of the side surface 3a near the end surface 3e. The first electrode layer E1 of the electrode portion 5a is located on the side surface 3a. The first electrode layer E1 does not have to be formed on the side surface 3a. That is, the first electrode layer E1 does not have to be disposed on the side surface 3a. The second electrode layer E2 of the electrode unit 5a is disposed on the first electrode layer E1 and the side surface 3a. In the electrode unit 5a, the second electrode layer E2 is formed on the first electrode layer E1 and the electrical insulating film EI so as to cover the first electrode layer E1 and a portion of the side surface 3c. In the electrode unit 5a, the second electrode layer E2 is in direct contact with the first electrode layer E1 and the electrical insulating film EI. The second electrode layer E2 of the electrode unit 5a directly covers a portion of the film portion EIa and is in direct contact with the film portion EIa. The second electrode layer E2 of the electrode unit 5a is formed on the first electrode layer E1 so as to directly cover the entire first electrode layer E1 of the electrode unit 5a. In the electrode unit 5a, the second electrode layer E2 indirectly covers the side surface 3a so that the first electrode layer E1 is located between the second electrode layer E2 and the side surface 3a. The second electrode layer E2 of the electrode unit 5a is located on the side surface 3a. Therefore, the second electrode layer E2 includes a portion located on the side surface 3a. The third electrode layer E3 of the electrode unit 5a is disposed on the second electrode layer E2. In the electrode unit 5a, the third electrode layer E3 covers the entire second electrode layer E2. In the electrode unit 5a, the third electrode layer E3 is in contact with the entire second electrode layer E2. That is, in the electrode unit 5a, the third electrode layer E3 is in direct contact with the second electrode layer E2. In the electrode unit 5a, the third electrode layer E3 is not in direct contact with the first electrode layer E1. The third electrode layer E3 of the electrode unit 5a is located on the side surface 3c.

[0040] The first electrode layer E1 of the electrode portion 5c is disposed on the side surface 3c and the ridge portion 3i. The first electrode layer E1 of the electrode portion 5c is formed on the electrical insulating film EI so as to cover a portion of the side surface 3c and the entire ridge portion 3i. The first electrode layer E1 of the electrode portion 5c is in contact with the electrical insulating film EI on the portion of the side surface 3c and on the ridge portion 3g. That is, in the electrode portion 5c, the first electrode layer E1 is in direct contact with the electrical insulating film EI (film portion EIc). The portion of the side surface 3c is indirectly covered by the first electrode layer E1, and the remaining portion excluding the portion is exposed from the first electrode layer E1. The portion of the side surface 3c is a partial region of the side surface 3c closer to the end face 3e. The first electrode layer E1 of the electrode portion 5c is located on the side surface 3c. The first electrode layer E1 does not have to be formed on the side surface 3c. That is, the first electrode layer E1 does not have to be disposed on the side surface 3c. The second electrode layer E2 of the electrode portion 5c is disposed on the first electrode layer E1 and the side surface 3c. In the electrode portion 5c, the second electrode layer E2 is formed on the first electrode layer E1 and the electrical insulating film EI so as to cover the first electrode layer E1 and a portion of the side surface 3c. In the electrode portion 5c, the second electrode layer E2 is in direct contact with the first electrode layer E1 and the electrical insulating film EI. The second electrode layer E2 of the electrode portion 5c directly covers a portion of the film portion EIc and is in direct contact with the film portion EIc. The second electrode layer E2 of the electrode portion 5c is formed on the first electrode layer E1 so as to directly cover the entire first electrode layer E1 of the electrode portion 5c. In the electrode portion 5c, the second electrode layer E2 indirectly covers the side surface 3c so that the first electrode layer E1 is located between the second electrode layer E2 and the side surface 3c. The second electrode layer E2 of the electrode portion 5c is located on the side surface 3c. Therefore, the second electrode layer E2 includes a portion located on the side surface 3c. The third electrode layer E3 of the electrode unit 5c is disposed on the second electrode layer E2. In the electrode unit 5c, the third electrode layer E3 covers the entire second electrode layer E2. In the electrode unit 5c, the third electrode layer E3 is in contact with the entire second electrode layer E2. That is, in the electrode unit 5c, the third electrode layer E3 is in direct contact with the second electrode layer E2. In the electrode unit 5c, the third electrode layer E3 is not in direct contact with the first electrode layer E1. The third electrode layer E3 of the electrode unit 5c is located on the side surface 3c.

[0041] The first electrode layer E1 of the electrode portion 5e is disposed on the end face 3e. The first electrode layer E1 of the electrode portion 5e is formed on the electrical insulating film EI so as to cover the entire end face 3e. The first electrode layer E1 of the electrode portion 5e is in contact with the electrical insulating film EI on the end face 3e. That is, in the electrode portion 5e, the first electrode layer E1 is in direct contact with the electrical insulating film EI (film portion EIe). The end face 3e is indirectly covered by the first electrode layer E1. The second electrode layer E2 of the electrode unit 5e is disposed on the first electrode layer E1. In the electrode unit 5e, the second electrode layer E2 is formed on the first electrode layer E1 so as to cover the entire first electrode layer E1. In the electrode unit 5e, the second electrode layer E2 is in direct contact with the first electrode layer E1. In the electrode unit 5e, the second electrode layer E2 indirectly covers the end face 3e so that the first electrode layer E1 is located between the second electrode layer E2 and the end face 3e. The second electrode layer E2 of the electrode unit 5e is located on the end face 3e. Therefore, the second electrode layer E2 includes a portion located on the end face 3e. The third electrode layer E3 of the electrode unit 5e is disposed on the second electrode layer E2. In the electrode unit 5e, the third electrode layer E3 covers the entire second electrode layer E2. In the electrode unit 5e, the third electrode layer E3 is in contact with the entire second electrode layer E2. That is, in the electrode unit 5e, the third electrode layer E3 is in direct contact with the second electrode layer E2. In the electrode unit 5e, the third electrode layer E3 is not in direct contact with the first electrode layer E1.

[0042] The electrical insulating film EI includes a portion covered by the external electrode 5 and a portion exposed from the external electrode 5. The film portion EIa has a portion covered by the electrode portion 5a and a portion exposed from the electrode portion 5a. The film portion EIc has a portion covered by the electrode portion 5c and a portion exposed from the electrode portion 5c. The portions of the electrical insulating film EI that are exposed from the external electrodes 5 are located in regions between the multiple external electrodes 5 on the surface of the element body 3. Therefore, the electrical insulating film EI includes film portions that are located at least in regions between the multiple external electrodes 5 on the surface of the element body 3. In other words, the electrical insulating film EI includes film portions that are located at least in regions that are exposed from the multiple external electrodes 5 on the surface of the element body 3.

[0043] The first electrode layer E1 is formed by baking a conductive paste applied to the surface of the element body 3. The first electrode layer E1 is formed on the electrical insulating film EI so as to cover the portion of the side surface 3a, the portion of the side surface 3c, one end face 3e, and the ridge portions 3g, 3i, and 3j. The first electrode layer E1 is formed by sintering a metal component (metal particles) contained in the conductive paste. The first electrode layer E1 is a sintered metal layer. The first electrode layer E1 is a sintered metal layer formed on the element body 3. In this embodiment, the first electrode layer E1 is a sintered metal layer made of Cu. The first electrode layer E1 may also be a sintered metal layer made of Ni. The first electrode layer E1 contains a base metal. The conductive paste contains, for example, particles made of Cu or Ni, a glass component, an organic binder, and an organic solvent. The first electrode layer E1 of each electrode portion 5a, 5c, and 5e is integrally formed.

[0044] As shown in Figures 4 and 5, the first electrode layer E1 is also physically connected to the corresponding internal electrodes 7 and 9. Figures 4 and 5 are schematic diagrams showing external electrodes, electrical insulating films, and internal electrodes. Hatching indicating cross sections is omitted in Figures 4 and 5. The electrical insulating film EI (film portion EIe) is not necessarily formed uniformly with a predetermined film thickness. That is, the material components constituting the electrical insulating film EI, such as silicon oxide, are not densely attached to the outer surface of the element body 3 but are sparsely attached. For this reason, the first electrode layer E1 may be partially directly connected to the corresponding internal electrodes 7, 9. When the conductive paste is heated, the material components constituting the electrical insulating film EI diffuse into the conductive paste, and the material components constituting the electrical insulating film EI and the conductive paste are mixed together. Therefore, even if the material components constituting the electrical insulating film EI are closely attached to the outer surface of the element body 3, the first electrode layer E1 can be partially directly connected to the corresponding internal electrodes 7, 9.

[0045] The second electrode layer E2 is formed by curing a conductive resin applied onto the first electrode layer E1. The second electrode layer E2 is formed over the first electrode layer E1 and the element body 3. The first electrode layer E1 is a base metal layer for forming the second electrode layer E2. The second electrode layer E2 is a conductive resin layer that covers the first electrode layer E1. The conductive resin includes, for example, a resin, a conductive material, and an organic solvent. The resin is, for example, a thermosetting resin. The conductive material is, for example, metal particles. The metal particles are, for example, silver particles or copper particles. In this embodiment, the second electrode layer E2 includes a plurality of silver particles. The thermosetting resin is, for example, a phenolic resin, an acrylic resin, a silicone resin, an epoxy resin, or a polyimide resin. The second electrode layer E2 is in contact with a portion of the ridge portion 3j. The second electrode layer E2 of each electrode portion 5a, 5c, 5e is integrally formed.

[0046] The third electrode layer E3 is formed by plating on the second electrode layer E2 and on the first electrode layer E1 (portions exposed from the second electrode layer E2). The third electrode layer E3 may have a multi-layer structure. In this case, the third electrode layer E3 has, for example, a Ni plating layer and a solder plating layer. The Ni plating layer is formed on the second electrode layer E2 and the first electrode layer E1. The solder plating layer is formed on the Ni plating layer. The solder plating layer covers the Ni plating layer. The Ni plating layer has better solder leach resistance than the metal contained in the second electrode layer E2. The third electrode layer E3 may have a Sn plating layer, a Cu plating layer, or an Au plating layer instead of the Ni plating layer. The solder plating layer includes, for example, a Sn plating layer, a Sn—Ag alloy plating layer, a Sn—Bi alloy plating layer, or a Sn—Cu alloy plating layer. The third electrode layer E3 of each electrode portion 5a, 5c, 5e is integrally formed.

[0047] 2, the internal electrode 7A faces, in the first direction D1, the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. When the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A are viewed from the first direction D1, the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A overlap each other. Therefore, an electric field is likely to be generated between the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. The film portion EIa is located between the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. The internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A face each other with the film portion EIa present between the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. The internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A face each other indirectly.

[0048] 2, the internal electrode 9A faces, in the first direction D1, the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A. When the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A are viewed from the first direction D1, the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A overlap each other. Therefore, an electric field is likely to be generated between the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A. The film portion EIa is located between the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A. The internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A face each other with the film portion EIa present between the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A. The internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A face each other indirectly.

[0049] 3, each of the multiple internal electrodes 7 faces, in the third direction D3, a second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. When each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7 are viewed from the third direction D3, each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7 overlap each other. Therefore, an electric field is also likely to be generated between each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. The film portion EIc is located between each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. Each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7 face each other, with the film portion EIc being present between each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. Each internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7 face each other indirectly.

[0050] 3, each of the multiple internal electrodes 9 faces, in the third direction D3, a second electrode layer E2 included in an electrode portion 5c that is not electrically connected to the internal electrode 9. When each internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9 are viewed from the third direction D3, the internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9 overlap each other. Therefore, an electric field is also likely to be generated between each internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9. The film portion EIc is located between each internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9. Each internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9 face each other, with the film portion EIc being present between each internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9. Each internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9 face each other indirectly.

[0051] The configuration of the multilayer capacitor C1 will be described with reference to Figs. 6 and 7. As described above, the multilayer capacitor C1 includes an element body 3, an electrical insulating film EI, and an external electrode 5. Figs. 6 and 7 are schematic diagrams showing a cross-sectional configuration of the multilayer capacitor. The third electrode layer E3 is not shown in Figs. 6 and 7. Hatching indicating a cross section is not shown in Figs. 6 and 7. In Fig. 7, similar to Fig. 3, the internal electrodes 7, 9 are intentionally shown shifted from each other in the third direction D3. Average thickness T of the membrane part EIa EIa is the average thickness T of the membrane part EIe EIe That's all. Average thickness T EIa The average thickness T is, for example, 0.02 μm or more. EIa The average thickness T may be 0.05 μm or more. EIe is, for example, greater than 0 and equal to or less than 0.2 μm.

[0052] The distance T between the internal electrode 7A and the side surface 3a facing the internal electrode 7A OL is, for example, 100 μm or more and 400 μm or less. OL is the distance between the internal electrode 7A and the side surface 3a in the first direction D1. Average thickness T EIa , interval T OL Ratio to (T EIa / T OL ) is, for example, 1.0×10 -4 That's all. EIa / T OL ) is 2.5 × 10 -4 It may be more than that. Although not shown in the drawings, the distance between the internal electrode 9A and the side surface 3a facing the internal electrode 9A is, for example, 100 μm or more and 400 μm or less. OL It may be the same as or different from. Average thickness T EIa to the distance between the internal electrode 9A and the side surface 3a facing the internal electrode 9A is, for example, 1.0×10 -4 That's all. Average thickness T EIato the distance between the internal electrode 9A and the side surface 3a facing the internal electrode 9A is 2.5×10 -4 It may be more than that.

[0053] Average thickness T of the membrane part EIc EIc is the average thickness T EIe That's all. Average thickness T EIc The average thickness T is, for example, 0.02 μm or more. EIc The average thickness T may be 0.05 μm or more. EIc is the average thickness T EIa It may be the same as or different from. Distance T between the internal electrodes 7, 9 and the side surface 3c W is, for example, 50 μm or more and 300 μm or less. Average thickness T EIc , interval T W Ratio to (T EIc / T W ) is, for example, 1.0×10 -4 That's all. EIa / T OL ) is 2.5 × 10 -4 It may be more than that.

[0054] The second electrode layer E2 (the second electrode layer E2 included in the electrode portion 5a) includes a portion E2a that is in contact with the electrical insulating film EI. E2a is, for example, 20 μm or more and 60 μm or less. Average thickness T EIa The maximum thickness T E2a Ratio to (T EIa / T E2a ) is, for example, 6.67×10 -4 That's all. EIa / T E2a ) is 1.67 × 10 -3 It may be more than that. The second electrode layer E2 (the second electrode layer E2 included in the electrode portion 5c) includes a portion E2c that is in contact with the electrical insulating film EI. E2c The maximum thickness T is, for example, 20 μm or more and 60 μm or less. E2c is the maximum thickness T E2aIt may be the same as or different from. Average thickness T EIc The maximum thickness T E2c Ratio to (T EIc / T E2c ) is, for example, 6.67×10 -4 That's all. EIc / T E2c ) is 1.67 × 10 -3 It may be more than that.

[0055] Length L of portion E2a in the second direction D2 E2a The length L is, for example, 30 μm or more and 500 μm or less. E2a is the distance in the second direction D2 between the edge of the second electrode layer E2 included in the electrode portion 5a and the edge of the first electrode layer E1 included in the electrode portion 5a. Average thickness T EIa of length L E2a Ratio to (T EIa / L E2a ) is, for example, 8.0×10 -5 That's all. EIa / L E2a ) is 2.0 × 10 -4 It may be more than that. Length L of portion E2c in the second direction D2 E2c The length L is, for example, 30 μm or more and 500 μm or less. E2c is the distance in the second direction D2 between the edge of the second electrode layer E2 included in the electrode portion 5c and the edge of the first electrode layer E1 included in the electrode portion 5c. Average thickness T EIc of length L E2c Ratio to (T EIa / L E2c ) is, for example, 8.0×10 -5 That's all. EIa / L E2c ) is 2.0 × 10 -4 It may be more than that.

[0056] Each average thickness T EIa ,T EIe ,T EIc For example, it can be calculated as follows: A cross-sectional photograph of the electrical insulating film EI including each of the film portions EIa and EIe is obtained. The cross-sectional photograph is a photograph of a cross section of the multilayer capacitor C1 cut along a plane perpendicular to the side surfaces 3a. The cross-sectional photograph is, for example, a photograph of a cross section of the multilayer capacitor C1 cut along a plane parallel to the pair of side surfaces 3c and equidistant from the pair of side surfaces 3c. The obtained cross-sectional photograph is subjected to image processing by software. This image processing distinguishes the boundaries of the electrical insulating film EI (each of the film portions EIa and EIe). The areas of each of the film portions EIa and EIe on the obtained cross-sectional photograph are calculated. The area of ​​the membrane portion EIa is divided by the length of the membrane portion EIa on the cross-sectional photograph, and the obtained quotient is the average thickness T EIa The area of ​​the membrane portion EIe is divided by the length of the membrane portion EIe on the cross-sectional photograph, and the obtained quotient is the average thickness T EIe Let's say. A cross-sectional photograph of the electrical insulating film EI including the film portion EIc is obtained. The cross-sectional photograph is a photograph of a cross section of the multilayer capacitor C1 cut along a plane perpendicular to the side surfaces 3c. The cross-sectional photograph is, for example, a photograph of a cross section of the multilayer capacitor C1 cut along a plane parallel to the pair of side surfaces 3a and equidistant from the pair of side surfaces 3a. The obtained cross-sectional photograph is subjected to image processing by software. This image processing identifies the boundary of the electrical insulating film EI (film portion EIc). The area of ​​the film portion EIc on the obtained cross-sectional photograph is calculated. The area of ​​the membrane portion EIc is divided by the length of the membrane portion EIc on the cross-sectional photograph, and the obtained quotient is the average thickness T EIc Let's say.

[0057] Interval T OL , maximum thickness T E2a , and length L E2a For example, it can be calculated as follows: A cross-sectional photograph of the element body 3 and the external electrode 5 including the electrode portion 5a is obtained. The cross-sectional photograph is a photograph of a cross section of the multilayer capacitor C1 cut along a plane perpendicular to the side surfaces 3a. The cross-sectional photograph is, for example, a photograph of a cross section of the multilayer capacitor C1 cut along a plane parallel to the pair of side surfaces 3c and equidistant from the pair of side surfaces 3c. The obtained cross-sectional photograph is subjected to image processing by software. This image processing distinguishes the boundary of the second electrode layer E2. The maximum thickness T on the obtained cross-sectional photograph is then measured. E2a , and length L E2a The image processing allows the boundary between the side surface 3a and the electrical insulating film EI, and the boundary between the element body 3 and the internal electrode 7A to be determined. OL is required.

[0058] Interval T W , maximum thickness T E2c , and length L E2c For example, it can be calculated as follows: A cross-sectional photograph of the element body 3 and the external electrode 5 including the electrode portion 5c is obtained. The cross-sectional photograph is a photograph of a cross section of the multilayer capacitor C1 cut along a plane perpendicular to the side surfaces 3c. The cross-sectional photograph is, for example, a photograph of a cross section of the multilayer capacitor C1 cut along a plane parallel to the pair of side surfaces 3a and equidistant from the pair of side surfaces 3a. The obtained cross-sectional photograph is subjected to image processing by software. This image processing distinguishes the boundary of the second electrode layer E2. The maximum thickness T on the obtained cross-sectional photograph is E2c , and length L E2c By the image processing, the boundary between the side surface 3c and the electrical insulating film EI, and the boundary between the element body 3 and the internal electrodes 7, 9 are determined. W is required.

[0059] Next, the average thickness T EIa , interval T OL , maximum thickness T E2a , and length L E2a The relationship between these two will be explained in detail. The inventors have determined that the average thickness TEIa , interval T OL , maximum thickness T E2a , and length L E2a In order to clarify the relationship between the average thickness T EIa Samples S1 to S3 with different properties were prepared, and the occurrence of migration was confirmed for each of samples S1 to S10. The results are shown in Figure 8. Figure 8 is a chart showing the occurrence of migration for each sample.

[0060] Each sample S1 to S10 has an average thickness T EIa The multilayer capacitors have the same structure except for the difference in the spacing T. In each of the samples S1 to S10, the height of the element body 3 is 1.6 mm, the width of the element body 3 is 1.6 mm, and the length of the element body 3 is 3.2 mm. The capacitance of each of the samples S1 to S10 is 2.2 μF. In each of the samples S1 to S10, the spacing T OL is 200 μm, and the maximum thickness T E2a is 30 μm, and the length L E2a is 250 μm. For sample S1, the average thickness T EIa That is, the sample S1 does not have an electrical insulating film EI. For sample S2, the average thickness T EIa In sample S3, the average thickness T EIa In sample S4, the average thickness T EIa In sample S5, the average thickness T EIa In sample S6, the average thickness T EIa In sample S7, the average thickness T EIa In sample S8, the average thickness T EIa In sample S9, the average thickness T EIa In sample S10, the average thickness T EIa is 0.5 μm.

[0061] The occurrence of migration is confirmed as follows. A high-temperature bias test is performed on each of the samples S1 to S10. In the high-temperature bias test, a predetermined voltage is applied to each of the samples S1 to S10 for a predetermined time in a high-temperature environment. In this test, the ambient temperature is 150°C, the applied voltage is 50V, and the voltage application time is 2000 hours. After the high temperature bias test, it is confirmed whether migration has occurred, and if migration has occurred, the maximum length of the migration is measured.

[0062] As a result of the above test, no migration was observed in each of the samples S6 to S10, as shown in Fig. 8. In contrast, migration was observed in each of the samples S1 to S5. In samples S1 to S4, the maximum migration length was 200 μm or more. In contrast, in sample S5, the maximum migration length was 62 μm. It was confirmed that sample S5 tends to suppress the occurrence of migration compared to samples S1 to S4. Under the conditions in which multilayer capacitors are actually used, the maximum length of migration is required to be 70 μm or less, and even more required to be 50 μm or less.

[0063] In the multilayer capacitor C1, the film portion EIa included in the electrical insulating film EI is located at least on the region between the plurality of external electrodes 5 on the surface of the element body 3. Therefore, even when metal particles included in the second electrode layer E2 are ionized, the film portion EIa inhibits the reaction between the generated metal ions and electrons supplied from the element body 3 or the external electrodes 5. In other words, electrons are less likely to be supplied to the metal ions. As a result, the multilayer capacitor C1 suppresses the occurrence of migration. In the multilayer capacitor C1, the film portion EIc included in the electrical insulating film EI is also located at least on the region between the plurality of external electrodes 5 on the surface of the element body 3. Therefore, the multilayer capacitor C1 further suppresses the occurrence of migration.

[0064] In a configuration in which the electrode unit 5a includes the second electrode layer E2, there is a risk that metal particles included in the second electrode layer E2 of the electrode unit 5a may be ionized. In the multilayer capacitor C1, the film portion EIa is located on the side surface 3a. Therefore, the film portion EIa reliably inhibits the reaction between metal ions generated from metal particles contained in the second electrode layer E2 of the electrode portion 5a and electrons supplied from the element body 3 or the external electrode 5. As a result, the multilayer capacitor C1 reliably suppresses the occurrence of migration.

[0065] In a configuration in which the electrode unit 5c includes the second electrode layer E2, there is a risk that metal particles included in the second electrode layer E2 of the electrode unit 5c may be ionized. In the multilayer capacitor C1, the film portion EIc is located on the side surface 3c. Therefore, the film portion EIc reliably inhibits the reaction between metal ions generated from metal particles contained in the second electrode layer E2 of the electrode portion 5c and electrons supplied from the element body 3 or the external electrode 5. As a result, the multilayer capacitor C1 reliably suppresses the occurrence of migration.

[0066] When the external electrode 5 includes the third electrode layer E3, the plating solution may infiltrate from the end face 3e into the element body 3. If the plating solution infiltrates into the element body 3, the electrical characteristics of the multilayer capacitor C1 may deteriorate. In the multilayer capacitor C1, the electrical insulating film EI includes the film portion EIe. Therefore, even when the external electrode 5 includes the third electrode layer E3, the film portion EIe prevents the plating solution from penetrating into the element body 3. As a result, the multilayer capacitor C1 suppresses deterioration of the electrical characteristics of the multilayer capacitor C1.

[0067] In the multilayer capacitor C1, the first electrode layer E1 is formed on the electrical insulating film EI. Therefore, even when metal particles contained in the second electrode layer E2 are ionized, electrons are less likely to be supplied by the metal ions. Therefore, the multilayer capacitor C1 further suppresses the occurrence of migration.

[0068] In the multilayer capacitor C1, the average thickness T EIa is the average thickness T EIeThis more reliably inhibits the reaction between metal ions generated from metal particles contained in the second electrode layer E2 of the electrode portion 5a and electrons supplied from the element body 3 or the external electrode 5. This more reliably inhibits the occurrence of migration in the multilayer capacitor C1. The configuration in which the electrical insulating film EI includes the film portion EIe may reduce the connectivity between the first electrode layer E1 and the internal electrodes 7, 9 corresponding to each other. In the multilayer capacitor C1, the average thickness T EIe is the average thickness T EIa Therefore, the multilayer capacitor C1 suppresses a decrease in the connectivity between the first electrode layer E1 and the internal electrodes 7, 9 corresponding to each other.

[0069] In the multilayer capacitor C1, the average thickness T EIa Therefore, the multilayer capacitor C1 reliably suppresses the occurrence of migration.

[0070] In the multilayer capacitor C1, the average thickness T EIe is greater than 0 and equal to or less than 0.2 μm. Therefore, the multilayer capacitor C1 reliably prevents deterioration of the electrical characteristics of the multilayer capacitor C1 and deterioration of the connectivity between the first electrode layer E1 and the internal electrodes 7, 9 corresponding to each other.

[0071] Interval T OL In the case where the distance T is less than 100 μm, electrons tend to be supplied from the internal electrodes 7A and 9A to the metal ions. OL is 100 μm or more. Therefore, in the multilayer capacitor C1, electrons are not easily supplied from the internal electrodes 7A, 9A to the metal ions. As a result, the multilayer capacitor C1 reliably suppresses the occurrence of migration. Interval T OL In the case of a structure in which the spacing T is greater than 400 μm, cracks tend to occur in the element body 3. OL Therefore, the multilayer capacitor C1 suppresses the occurrence of cracks in the element body 3.

[0072] An electric field is likely to be generated between the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. In this case, the generated electric field acts on the metal particles included in the second electrode layer E2, and the metal particles are likely to be ionized. In the multilayer capacitor C1, the film portion EIa is located between the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. Therefore, an electric field is unlikely to be generated between the internal electrode 7A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 7A. In the multilayer capacitor C1, the film portion EIa is located between the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A. Therefore, an electric field is unlikely to be generated between the internal electrode 9A and the second electrode layer E2 included in the electrode portion 5a that is not electrically connected to the internal electrode 9A. As a result, the multilayer capacitor C1 further suppresses the occurrence of migration.

[0073] An electric field is likely to be generated between the internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. In this case, the generated electric field acts on the metal particles included in the second electrode layer E2, and the metal particles are likely to be ionized. In the multilayer capacitor C1, the film portion EIc is located between the internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. Therefore, an electric field is unlikely to be generated between the internal electrode 7 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 7. In the multilayer capacitor C1, the film portion EIc is located between the internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9. Therefore, an electric field is unlikely to be generated between the internal electrode 9 and the second electrode layer E2 included in the electrode portion 5c that is not electrically connected to the internal electrode 9. As a result, the multilayer capacitor C1 further suppresses the occurrence of migration.

[0074] In the multilayer capacitor C1, the external electrodes 5 include a third electrode layer E3, and the second electrode layer E2 is covered with the third electrode layer E3. Therefore, even if metal particles contained in the second electrode layer E2 are ionized, the third electrode layer E3 suppresses the occurrence of migration. As a result, the multilayer capacitor C1 further suppresses the occurrence of migration. In the multilayer capacitor C1, the third electrode layer E3 suppresses peeling of the second electrode layer E2.

[0075] In the multilayer capacitor C1, the electrical insulating film EI and the second electrode layer E2 are in contact with each other. Therefore, the multilayer capacitor C1 reliably suppresses the supply of electrons to metal ions. The multilayer capacitor C1 reliably suppresses the occurrence of migration.

[0076] In the multilayer capacitor C1, the electrical insulating film EI is made of a silicon oxide film. Silicon oxide films have high electrical insulation properties. Silver does not easily diffuse into silicon oxide films. Therefore, even if the second electrode layer E2 contains a plurality of silver particles, the electrical insulation properties of the electrical insulating film EI can be maintained. As a result, the multilayer capacitor C1 reliably suppresses the occurrence of migration.

[0077] The second electrode layer E2 contains a plurality of silver particles, which tend to migrate more easily than, for example, copper particles. The multilayer capacitor C1 reliably suppresses the occurrence of migration even when the second electrode layer E2 contains a plurality of silver particles.

[0078] Next, the structure of a multilayer capacitor C2 according to a modified example of this embodiment will be described with reference to Figs. 9 and 10. Figs. 9 and 10 are diagrams showing the cross-sectional structure of the multilayer capacitor according to the modified example of this embodiment. The multilayer capacitor C2 according to this modified example is generally similar to or the same as the multilayer capacitor C1 described above, but this modified example differs from the present embodiment described above in terms of the structures of the external electrodes 5 and the electrical insulating film EI. Below, the differences between this modified example and the present embodiment described above will be mainly described.

[0079] 9 and 10, the external electrode 5 is disposed directly on the element body 3. The external electrode 5 is formed on the element body 3 so as to cover five surfaces, namely, a pair of side surfaces 3a, one end surface 3e, and a pair of side surfaces 3c, as well as the ridge portions 3g, 3i, and 3j.

[0080] The first electrode layer E1 of the electrode portion 5a is formed on the element body 3 so as to cover part of the side surface 3a and the entire ridge portion 3g. The first electrode layer E1 of the electrode portion 5a contacts the element body 3 on the part of the side surface 3a and on the ridge portion 3g. That is, in the electrode portion 5a, the first electrode layer E1 is in direct contact with the element body 3. The part of the side surface 3a is directly covered by the first electrode layer E1, and the remaining part excluding the part is exposed from the first electrode layer E1. In the electrode unit 5a, the second electrode layer E2 is formed on the first electrode layer E1 and the element body 3 so as to cover the first electrode layer E1 and part of the side surface 3c. In the electrode unit 5a, the second electrode layer E2 is in direct contact with the first electrode layer E1 and the element body 3. In the electrode unit 5a, the second electrode layer E2 indirectly covers the side surface 3a so that the first electrode layer E1 is located between the second electrode layer E2 and the side surface 3a. In the electrode unit 5a, the second electrode layer E2 also directly covers the side surface 3a.

[0081] The first electrode layer E1 of the electrode portion 5c is formed on the element body 3 so as to cover part of the side surface 3c and the entire ridge portion 3i. The first electrode layer E1 of the electrode portion 5c is in contact with the element body 3 on the part of the side surface 3c and on the ridge portion 3g. That is, in the electrode portion 5c, the first electrode layer E1 is in direct contact with the element body 3. The part of the side surface 3c is directly covered by the first electrode layer E1, and the remaining part excluding the part is exposed from the first electrode layer E1. In the electrode unit 5c, the second electrode layer E2 is formed on the first electrode layer E1 and the element body 3 so as to cover the first electrode layer E1 and part of the side surface 3c. In the electrode unit 5c, the second electrode layer E2 is in direct contact with the first electrode layer E1 and the element body 3. In the electrode unit 5c, the second electrode layer E2 indirectly covers the side surface 3c so that the first electrode layer E1 is located between the second electrode layer E2 and the side surface 3c. In the electrode unit 5c, the second electrode layer E2 also directly covers the side surface 3c.

[0082] 9 and 10, the electrical insulating film EI includes a plurality of film portions EIa and EIc. The electrical insulating film EI includes a pair of film portions EIa and a pair of film portions EIc. In this modification, the electrical insulating film EI does not include the film portion EIe. That is, the end face 3e is exposed from the electrical insulating film EI. The electrical insulating film EI includes a plurality of film portions respectively arranged on each ridge portion 3j. The film portion EIa and the film portion EIc are connected by the film portion arranged on the ridge portion 3j. The membrane portion EIa is disposed in a region of the side surface 3a that is exposed from the second electrode layer E2 included in the electrode portion 5a. That is, the membrane portion EIa does not include a portion that is covered with the second electrode layer E2 included in the electrode portion 5a. The membrane portion EIa includes only a region that is exposed from the second electrode layer E2 included in the electrode portion 5a. The membrane portion EIa may be in contact with the second electrode layer E2 or may be spaced apart from the second electrode layer E2. The film portion EIc is disposed in a region of the side surface 3c that is exposed from the second electrode layer E2 included in the electrode portion 5c. That is, the film portion EIc does not include a portion that is covered with the second electrode layer E2 included in the electrode portion 5c. The film portion EIc includes only a region that is exposed from the second electrode layer E2 included in the electrode portion 5c. The film portion EIc may be in contact with the second electrode layer E2 or may be spaced apart from the second electrode layer E2.

[0083] In the multilayer capacitor C2 as well, the film portion EIa is located at least on the region between the plurality of external electrodes 5 on the surface of the element body 3. Therefore, the multilayer capacitor C2 suppresses the occurrence of migration as described above. The film portion EIc is also located at least on the region between the plurality of external electrodes 5 on the surface of the element body 3. Therefore, as described above, the multilayer capacitor C2 further suppresses the occurrence of migration.

[0084] In this specification, when an element is described as being disposed on another element, the element may be directly disposed on the other element or indirectly disposed on the other element. When an element is indirectly disposed on another element, an intervening element is present between the element and the other element. When an element is directly disposed on the other element, an intervening element is not present between the element and the other element. In this specification, when an element is described as being located on another element, the element may be directly located on the other element or indirectly located on the other element. When an element is indirectly located on another element, an intervening element is present between the element and the other element. When an element is directly located on the other element, an intervening element is not present between the element and the other element. In this specification, when an element is described as covering another element, the element may directly cover the other element or may indirectly cover the other element. When an element indirectly covers the other element, an intervening element exists between the element and the other element. When an element directly covers the other element, an intervening element does not exist between the element and the other element.

[0085] Although the embodiments of the present invention have been described above, the present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

[0086] In the present embodiment and the modified examples, a multilayer capacitor has been described as an example of an electronic component, but applicable electronic components are not limited to multilayer capacitors. Applicable electronic components include, for example, multilayer electronic components such as multilayer inductors, multilayer varistors, multilayer piezoelectric actuators, multilayer thermistors, and multilayer composite components, as well as electronic components other than multilayer electronic components. [Explanation of symbols]

[0087] 3…body, 3a, 3c…side surface, 3e…end surface, 5…external electrode, 5a, 5c, 5e…electrode portion, 7, 7A, 9, 9A…internal electrode, C1, C2…layered core, E1…first electrode layer, E2…second electrode layer, E3…third electrode layer, EI…electric insulating film, EIa, EIc, EIe…film portion.

Claims

1. a dielectric ceramic element; a plurality of external electrodes disposed on the element body; a plurality of internal electrodes arranged in the element body so as to face each other and electrically connected to corresponding external electrodes among the plurality of external electrodes; an electrical insulating film disposed on the element body, each of the plurality of external electrodes includes a conductive resin layer; the electrical insulating film includes a film portion located at least on an area between the plurality of external electrodes on the surface of the element body, The element body is a first side surface facing an outermost internal electrode among the plurality of internal electrodes in a direction in which the plurality of internal electrodes face each other; a pair of end surfaces facing each other and adjacent to the first side surface, the membrane portion is located on the first side; the conductive resin layer includes a portion located on the first side surface and in contact with the film portion, The ratio of the average thickness of the film portion located on the first side surface to the distance between the first side surface and the outermost internal electrode is 1.0×10 －４ That's all, The ratio of the average thickness of the film portion located on the first side surface to the maximum thickness of the portion of the conductive resin layer located on the first side surface and in contact with the film portion is 6.67×10 －４ That's all, The ratio of the average thickness of the film portion located on the first side surface to the length of the portion of the conductive resin layer located on the first side surface and in contact with the film portion in the direction in which the pair of end surfaces face each other is 8.0 × 10 －５ That's it, electronic components.

2. the element body further includes a second side surface extending in the direction in which the plurality of internal electrodes face each other, the membrane portion is located on the second side; the conductive resin layer includes a portion located on the second side surface and in contact with the film portion, The ratio of the average thickness of the film portion located on the second side surface to the distance between the second side surface and the internal electrode is 1.0×10 －４ That's all, The ratio of the average thickness of the film portion located on the second side surface to the maximum thickness of the portion of the conductive resin layer located on the second side surface and in contact with the film portion is 6.67×10 －４ That's all, The ratio of the average thickness of the film portion located on the second side surface to the length of the portion of the conductive resin layer located on the second side surface and in contact with the film portion in the direction in which the pair of end surfaces face each other is 8.0 × 10 －５ The electronic component according to claim 1 .

3. a corresponding one of the plurality of internal electrodes is exposed on each of the pair of end surfaces; The electronic component according to claim 1 , wherein the electrical insulating film further includes a film portion located on the end surface.

4. Each of the plurality of external electrodes further includes a sintered metal layer formed on the electrical insulating film and physically and electrically connected to the corresponding internal electrode, The electronic component according to claim 3 , wherein the conductive resin layer is formed on the sintered metal layer.

5. The electronic component according to claim 4 , wherein the average thickness of the film portion located on the first side surface is equal to or greater than the average thickness of the film portion located on the end surface.

6. The electronic component according to claim 5 , wherein the average thickness of the film portion located on the first side surface is 0.05 μm or more.

7. 7. The electronic component according to claim 5, wherein the average thickness of the film portion located on the end face is greater than 0 and not more than 0.2 [mu]m.

8. The electronic component according to any one of claims 5 to 7, wherein the distance between the outermost internal electrode and the first side surface is 100 µm or more and 400 µm or less.

9. the outermost internal electrode and the portion of the conductive resin layer located on the first side surface are not electrically connected to each other, The electronic component according to any one of claims 1 to 8, wherein the film portion located on the first side surface is further located between the outermost internal electrode and the portion of the conductive resin layer located on the first side surface.

10. 10. The electronic component according to claim 1, wherein each of the plurality of external electrodes further includes a plating layer formed on the conductive resin layer so as to cover the conductive resin layer.

11. 11. The electronic component according to claim 1, wherein the electrical insulating film and the conductive resin layer are in contact with each other.

12. The electronic component according to any one of claims 1 to 11, wherein the electrically insulating film is made of an electrically insulating thin film.

13. 13. The electronic component according to claim 1, wherein the electrical insulating film is made of a silicon oxide film.

14. The electronic component according to any one of claims 1 to 13, wherein the conductive resin layer contains a plurality of silver particles.

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