Electronic Components

Abstract

To provide an electronic component capable of suppressing occurrence of migration even in a case where an external electrode includes a conductive resin layer.SOLUTION: A length L11 of an internal electrode 7A in a third direction D3 from a reference plane PL1 is larger than a length L21 in the third direction D3 from the reference plane PL1 to an edge E2e of a second electrode layer E2 electrically connected with the internal electrode 7A. The length L11 is smaller than a length L31 from the reference plane PL1 to an edge E2e of a second electrode layer E2 not being electrically connected with the internal electrode 7A. A length L12 of an internal electrode 9A in the third direction D3 from a reference plane PL2 is larger than a length L22 in the third direction D3 from the reference plane PL2 to an edge E2e of a second electrode layer E2 electrically connected with the internal electrode 9A. The length L12 is smaller than a length L32 from the reference plane PL2 to an edge E2e of a second electrode layer E2 not being electrically connected with the internal electrode 9A.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] A known electronic component includes a rectangular parallelepiped element body, multiple external electrodes, and multiple internal electrodes (see, for example, Patent Document 1). The element body has a pair of main surfaces facing each other in a first direction, a pair of end surfaces facing each other in a second direction, and a pair of side surfaces facing each other in a third direction. The multiple external electrodes are respectively arranged on both end portions of the element body in the second direction. The multiple internal electrodes are arranged within the element body so as to be aligned in the third direction, and are exposed at corresponding one of the pair of end surfaces. Each external electrode has a pair of electrode portions respectively arranged on the pair of side surfaces and a pair of electrode portions respectively arranged on the pair of main surfaces. Each electrode portion 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 resin. In this case, migration may occur in the external electrodes. Migration is thought to occur, for example, due to the following events: An electric field generated between an outermost internal electrode, which is located outermost in the third direction among the multiple internal electrodes, and an electrode portion to which the outermost internal electrode is not electrically connected acts on the metal particles, ionizing the atoms of 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 metal ions migrate from the conductive resin layer react with electrons supplied from the element body, for example, and are deposited as metal on the surface of the element body.

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

[0006] An electronic component according to one aspect of the present invention includes a rectangular parallelepiped element body, multiple external electrodes, and multiple internal electrodes. The element body has a pair of main surfaces facing each other in a first direction, a pair of end surfaces facing each other in a second direction, and a pair of side surfaces facing each other in a third direction. The multiple external electrodes are respectively arranged on both end portions of the element body in the second direction. The multiple internal electrodes are arranged within the element body so as to be aligned in the third direction and are exposed at corresponding one of the pair of end surfaces. Each external electrode has a pair of first electrode portions each arranged on the pair of side surfaces and including a conductive resin layer, and a pair of second electrode portions each arranged on the pair of main surfaces and not including a conductive resin layer. Of the two conductive resin layers located on the same side surface, one conductive resin layer has an edge facing the other conductive resin layer. Of the multiple internal electrodes, the outermost internal electrode located outermost in the third direction is adjacent in the third direction to the first electrode portion to which the outermost internal electrode is electrically connected. Using a plane including the end face as a reference plane, a first length of the outermost internal electrode in a second direction from the reference plane is greater than a second length in the second direction from the reference plane to an edge of the conductive resin layer to which the outermost internal electrode is electrically connected, and is smaller than a third length in the second direction from the reference plane to an edge of the conductive resin layer to which the outermost internal electrode is not electrically connected.

[0007] In one embodiment, the first length is greater than the second length. Therefore, the internal electrode adjacent to the outermost internal electrode in the third direction and the conductive resin layer included in the first electrode portion adjacent to the same outermost internal electrode in the third direction are not electrically connected to each other, but are unlikely to face each other in the third direction. An electric field is unlikely to be generated between the conductive resin layer and the internal electrode that are not electrically connected to each other. The first length is shorter than the third length. Therefore, the outermost internal electrode is unlikely to face, in the third direction, a conductive resin layer included in a first electrode portion to which the outermost internal electrode is not electrically connected. An electric field is unlikely to be generated between the conductive resin layer and the outermost internal electrode that are not electrically connected to each other. The second electrode portion does not include a conductive resin layer, and therefore, the conductive resin layer and the internal electrode that are not electrically connected to each other do not face each other in the first direction. As a result, the above-described one aspect suppresses the occurrence of migration.

[0008] The above-mentioned one aspect may include a dummy conductor located in the same layer as the outermost internal electrode and spaced apart from the outermost internal electrode, and the dummy conductor may be electrically connected to an external electrode that is not electrically connected to the outermost internal electrode located in the same layer as the dummy conductor. In a configuration in which the dummy conductor is located in the same layer as the outermost internal electrode, structural defects are less likely to occur in the element.

[0009] In the above one aspect, each external electrode may have a third electrode portion disposed on an end surface and including a conductive resin layer. The configuration in which the external electrode has the third electrode portion relieves stress acting on the solder fillet formed on the third electrode portion, and suppresses the occurrence of solder cracks.

[0010] In the one aspect, when the internal electrode that is not electrically connected to the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is electrically connected are viewed from a third direction, the internal electrode that is not electrically connected to the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is electrically connected may overlap each other. In this case, the length of the internal electrodes in the second direction increases, making it possible to increase the capacitance.

[0011] In the above-described one aspect, the conductive resin layer may contain a plurality of silver particles.

[0012] According to another aspect of the present invention, an electronic component includes a rectangular parallelepiped body having a pair of main surfaces facing each other in a first direction, a pair of end surfaces facing each other in a second direction, and a pair of side surfaces facing each other in a third direction, a plurality of external electrodes respectively disposed on both end surfaces of the body in the second direction, and a plurality of internal electrodes disposed within the body so as to be aligned in the third direction and exposed at corresponding one of the pair of end surfaces. Each external electrode has a pair of first electrode portions each disposed on the pair of side surfaces and including a conductive resin layer, and a pair of second electrode portions each disposed on the pair of main surfaces and not including a conductive resin layer. Of the plurality of internal electrodes, an outermost internal electrode positioned outermost in the third direction has a first end exposed at the end surface and a second end facing the first end in the second direction and located within the body. When the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is electrically connected are viewed from the third direction, the second end is exposed from the conductive resin layer. When the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is not electrically connected are viewed from a third direction, the outermost internal electrode and the conductive resin layer do not overlap each other.

[0013] In the above-mentioned another aspect, the internal electrode adjacent to the outermost internal electrode in the third direction and the conductive resin layer included in the first electrode portion adjacent to the same outermost internal electrode in the third direction are not electrically connected to each other, but are unlikely to face each other in the third direction, and an electric field is unlikely to be generated between the conductive resin layer and the internal electrode that are not electrically connected to each other. The outermost internal electrode is unlikely to face, in the third direction, a conductive resin layer included in a first electrode portion to which the outermost internal electrode is not electrically connected, and an electric field is unlikely to be generated between the conductive resin layer and the outermost internal electrode that are not electrically connected to each other. The second electrode portion does not include a conductive resin layer, and therefore, the conductive resin layer and the internal electrode that are not electrically connected to each other do not face each other in the first direction. As a result, the above-mentioned another aspect suppresses the occurrence of migration. [Effects of the Invention]

[0014] Each aspect of the present invention provides an electronic component that suppresses the occurrence of migration even when the external electrodes include a conductive resin layer. [Brief explanation of the drawings]

[0015] [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 diagram showing a cross-sectional structure of the multilayer capacitor in accordance with this embodiment. [Figure 5] FIG. 5 is a diagram showing a cross-sectional structure of the multilayer capacitor in accordance with this embodiment. [Figure 6] FIG. 6 is a diagram showing a mounting structure of the multilayer capacitor in accordance with this embodiment. [Figure 7] FIG. 7 is a diagram showing a mounting structure of the multilayer capacitor in accordance with this embodiment. [Figure 8] FIG. 8 is a diagram showing a cross-sectional structure of a multilayer capacitor according to a modified example of this embodiment. [Figure 9] FIG. 9 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

[0016] 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.

[0017] The configuration of the multilayer capacitor C1 in accordance with this embodiment will be described with reference to Figures 1 to 5. Figure 1 is a perspective view of the multilayer capacitor in accordance with this embodiment. Figures 2, 3, 4, and 5 are views showing cross-sectional configurations of the multilayer capacitor in accordance with this embodiment. In this embodiment, the electronic component is, for example, the multilayer capacitor C1.

[0018] As shown in Fig. 1, the multilayer capacitor C1 includes a rectangular parallelepiped element body 3 and a plurality of external electrodes 5. In this embodiment, the multilayer capacitor C1 includes 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.

[0019] The element body 3 has a pair of principal 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 principal 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 principal 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 principal surface 3a faces the electronic device. The one principal surface 3a is arranged to form a mounting surface. The one principal surface 3a is the mounting surface.

[0020] The first direction D1 is a direction perpendicular to each main surface 3a and perpendicular to the third direction D3. The second direction D2 is a direction parallel to each main 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.

[0021] 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.

[0022] The pair of side surfaces 3c extend in the first direction D1 to connect the pair of main 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 main surfaces 3a. The pair of end surfaces 3e also extend in the third direction D3.

[0023] 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 main surface 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 main surface 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 has been subjected to so-called R-chamfering. The end face 3e and the main surface 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 main surface 3a and the side face 3c are indirectly adjacent to each other via the ridge lines 3j.

[0024] The element body 3 is configured by stacking multiple dielectric layers in the third direction D3. 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 third direction D3. 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.

[0025] As shown in FIGS. 2 to 5, the multilayer capacitor C1 includes a plurality of internal electrodes 7 and a plurality of internal electrodes 9. Each of the internal electrodes 7, 9 is an internal conductor disposed within the element body 3. Each of the internal electrodes 7, 9 is made of a conductive material that is typically used as an internal conductor for a multilayer electronic component. The conductive material includes, for example, a base metal. The conductive material includes, for example, Ni or Cu. The internal electrodes 7, 9 are configured as a sintered body of a conductive paste containing the conductive material. In this embodiment, the internal electrodes 7, 9 are made of Ni.

[0026] The internal electrodes 7 and the internal electrodes 9 are arranged at different positions (layers) in the third direction D3. 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 third direction D3. 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 internal electrodes 7 and the internal electrodes 9 are alternately arranged in the third direction D3. The internal electrodes 7 and 9 are arranged in the element body 3 so as to be aligned in the third direction D3. Each of the internal electrodes 7 and 9 is located in a plane substantially parallel to the side surface 3c. The internal electrodes 7 and 9 face each other in the third direction D3. The direction in which the internal electrodes 7 and 9 face each other (third direction D3) is perpendicular to the direction parallel to the side surface 3c (first direction D1 and second direction D2).

[0027] In this embodiment, the multiple internal electrodes 7 include one internal electrode 7A located outermost in the third direction D3. The internal electrode 7A is the outermost internal electrode. The internal electrode 7A has a pair of ends 7Ae1, 7Ae2 facing each other in the second direction D2. The end 7Ae1 is exposed at the end face 3e. The end 7Ae2 is located within the element body 3. In this embodiment, the multiple internal electrodes 9 include one internal electrode 9A located outermost in the third direction D3. The internal electrode 9A is the outermost internal electrode. The internal electrode 9A has a pair of ends 9Ae1, 9Ae2 facing each other in the second direction D2. The end 9Ae1 is exposed at the end face 3e. The end 9Ae2 is located within the element body 3. For example, if each end 7Ae1, 9Ae1 constitutes a first end, then the ends 7Ae2, 9Ae2 constitute a second end.

[0028] As shown in FIG. 1, the external electrodes 5 are arranged on both ends of the element body 3 in the second direction D2. Each external electrode 5 is arranged on the corresponding end face 3e of the element body 3. In this embodiment, each external electrode 5 is arranged on a pair of main faces 3a, a pair of side faces 3c, and one end face 3e. As shown in FIGS. 2 to 5, the external electrode 5 has a plurality of electrode portions 5a, 5c, 5e. The electrode portion 5a is arranged on the main faces 3a and on the ridge portions 3g. The electrode portions 5c are arranged on the side faces 3c and on the ridge portions 3i. The electrode portions 5e are arranged on the end faces 3e. The external electrode 5 also has an electrode portion arranged on the ridge portions 3j.

[0029] The external electrode 5 is formed on five surfaces, including the pair of main surfaces 3a, one end surface 3e, and the pair of side surfaces 3c, as well as on the ridge portions 3g, 3i, and 3j. Adjacent electrode portions 5a, 5c, and 5e are connected and electrically connected. The electrode portion 5e covers one end of the corresponding internal electrode 7, 9. The electrode portion 5e is directly connected to the corresponding internal electrode 7, 9. The external electrode 5 is electrically connected to the corresponding internal electrode 7, 9. As shown in FIGS. 2 to 5, the external electrode 5 has 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 and 5e has a first electrode layer E1 and a third electrode layer E3. Each of the electrode portions 5c has a first electrode layer E1, a second electrode layer E2, and a third electrode layer E3.

[0030] The first electrode layer E1 of the electrode portion 5a is disposed on the principal surface 3a and the ridge portion 3g. The first electrode layer E1 of the electrode portion 5a is formed so as to cover a portion of the principal surface 3a and the entire ridge portion 3g. The first electrode layer E1 of the electrode portion 5a is in contact with the portion of the principal surface 3a and the entire 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 portion of the principal surface 3a is 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 principal surface 3a is a partial region of the principal surface 3a closer to the end face 3e. The first electrode layer E1 of the electrode portion 5a is located on the principal surface 3a. The first electrode layer E1 does not have to be formed on the principal surface 3a. That is, the first electrode layer E1 does not have to be disposed on the principal surface 3a. The third electrode layer E3 of the electrode unit 5a is disposed on the first electrode layer E1. In the electrode unit 5a, the third electrode layer E3 covers the entire first electrode layer E1. In the electrode unit 5a, the third electrode layer E3 is in contact with the entire first electrode layer E1. That is, in the electrode unit 5a, the third electrode layer E3 is in direct contact with the first electrode layer E1. The third electrode layer E3 of the electrode unit 5a is located on the main surface 3a. The electrode portion 5a has a two-layer structure.

[0031] 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 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 portion of the side surface 3c and the entire ridge portion 3i. That is, in the electrode portion 5c, the first electrode layer E1 is in direct contact with the element body 3. The portion of the side surface 3c is 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 unit 5c is disposed on the first electrode layer E1 and the side surface 3c. In the electrode unit 5c, the second electrode layer E2 is formed so as to cover the first electrode layer E1 and a portion 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 side surface 3c. The second electrode layer E2 of the electrode unit 5c is formed so as to cover the entire first electrode layer E1 of the electrode unit 5c. 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. The second electrode layer E2 of the electrode unit 5c is located on the side surface 3c. Each second electrode layer E2 located on the same side surface 3c has an edge E2e. On the same side surface 3c, the edge E2e of one second electrode layer E2 faces the edge E2e of the other second electrode layer E2. 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. The electrode portion 5c has a three-layer structure.

[0032] The first electrode layer E1 of the electrode unit 5e is disposed on the end surface 3e. The first electrode layer E1 of the electrode unit 5e is formed so as to cover the entire end surface 3e. The first electrode layer E1 of the electrode unit 5e is in contact with the entire end surface 3e. That is, in the electrode unit 5e, the first electrode layer E1 is in direct contact with the end surface 3e. The third electrode layer E3 of the electrode unit 5e is disposed on the first electrode layer E1. In the electrode unit 5e, the third electrode layer E3 covers the entire first electrode layer E1. In the electrode unit 5e, the third electrode layer E3 is in contact with the entire first electrode layer E1. That is, in the electrode unit 5e, the third electrode layer E3 is in direct contact with the first electrode layer E1. The third electrode layer E3 of the electrode unit 5e is located on the end surface 3e. The electrode portion 5e has a two-layer structure.

[0033] 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 so as to cover the portion of the main 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.

[0034] 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 contains, 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 contains 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.

[0035] 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.

[0036] The electrode portion 5a does not include the second electrode layer E2. The electrode portion 5c includes the second electrode layer E2. For example, when the electrode portion 5c constitutes the first electrode portion, the electrode portion 5a constitutes the second electrode portion, and the electrode portion 5e constitutes the third electrode portion. In this embodiment, the electrode portion 5e does not include the second electrode layer E2.

[0037] The internal electrode 7A is adjacent to the electrode portion 5c electrically connected to the internal electrode 7A in the third direction D3. The internal electrode 7A is adjacent to the electrode portion 5c located on the side surface 3c adjacent to the internal electrode 7A in the third direction D3. The internal electrode 9A is adjacent to the electrode portion 5c electrically connected to the internal electrode 9A in the third direction D3. The internal electrode 9A is adjacent to the electrode portion 5c located on the side surface 3c adjacent to the internal electrode 9A in the third direction D3.

[0038] 2 to 5, the multilayer capacitor C1 includes a plurality of conductors 11 and 13. In this embodiment, the multilayer capacitor C1 includes two conductors 11 and 13. For ease of explanation, in FIGS. 3 and 4, the internal electrodes 7 and 9 (internal electrodes 7A and 9A) and the conductors 11 and 13 are intentionally illustrated as being shifted from each other in the first direction D1. The conductor 11 is located in the same layer as the internal electrode 7A and is spaced apart from the internal electrode 7A. The conductor 11 has one end exposed at the corresponding end face 3e. One end of the conductor 11 is exposed at the end face 3e where one end of the internal electrode 9 is exposed. One end of the conductor 11 is completely covered by the corresponding electrode portion 5e. The conductor 11 is directly connected to the corresponding electrode portion 5e. The conductor 11 is electrically connected to the corresponding external electrode 5. In this embodiment, the conductor 11 is electrically connected to the external electrode 5 (electrode portion 5e) to which the internal electrode 9 is electrically connected. In other words, the conductor 11 is electrically connected to the external electrode 5 to which the internal electrode 7 is not electrically connected. The conductor 13 is located in the same layer as the internal electrode 9A and is spaced apart from the internal electrode 9A. The conductor 13 has one end exposed at the corresponding end face 3e. One end of the conductor 13 is exposed at the end face 3e where one end of the internal electrode 7 is exposed. One end of the conductor 13 is completely covered by the corresponding electrode portion 5e. The conductor 13 is directly connected to the corresponding electrode portion 5e. The conductor 13 is electrically connected to the corresponding external electrode 5. In this embodiment, the conductor 13 is electrically connected to the external electrode 5 (electrode portion 5e) to which the internal electrode 7 is electrically connected. In other words, the conductor 13 is electrically connected to the external electrode 5 to which the internal electrode 9 is not electrically connected. The conductors 11 and 13 constitute dummy conductors that are unlikely to contribute to the formation of capacitance.

[0039] 2, the length L11 of the internal electrode 7A in the second direction D2 from the reference plane PL1 is greater than the length L21 in the second direction D2 from the reference plane PL1 to the end edge E2e of the second electrode layer E2 electrically connected to the internal electrode 7A. Therefore, when the internal electrode 7A and the second electrode layer E2 electrically connected to the internal electrode 7A are viewed from the third direction D3, e2 are exposed from the second electrode layer E2 to which the internal electrode 7A is electrically connected. The length L11 is shorter than the length L31 in the second direction D2 from the reference plane PL1 to the edge E2e of the second electrode layer E2 to which the internal electrode 7A is not electrically connected. Therefore, when the internal electrode 7A and the second electrode layer E2 to which the internal electrode 7A is not electrically connected are viewed from the third direction D3, the internal electrode 7A and the second electrode layer E2 to which the internal electrode 7A is not electrically connected do not overlap each other. The reference plane PL1 includes the end surface 3e where the end 7Ae1 of the internal electrode 7A is exposed. For example, when the length L11 constitutes the first length, the length L21 constitutes the second length, and the length L31 constitutes the third length.

[0040] The length L12 of the internal electrode 9A in the second direction D2 from the reference plane PL2 is greater than the length L22 in the second direction D2 from the reference plane PL2 to the end edge E2e of the second electrode layer E2 electrically connected to the internal electrode 9A. Therefore, when the internal electrode 9A and the second electrode layer E2 electrically connected to the internal electrode 9A are viewed from the third direction D3, the end 9A e2 are exposed from the second electrode layer E2 to which the internal electrode 9A is electrically connected. The length L12 is smaller than the length L32 in the second direction D2 from the reference plane PL2 to the edge E2e of the second electrode layer E2 to which the internal electrode 9A is not electrically connected. Therefore, when the internal electrode 9A and the second electrode layer E2 to which the internal electrode 9A is not electrically connected are viewed from the third direction D3, the internal electrode 9A and the second electrode layer E2 to which the internal electrode 9A is not electrically connected do not overlap each other. The reference plane PL2 includes the end surface 3e where the end 9Ae1 of the internal electrode 9A is exposed. For example, when the length L12 constitutes the first length, the length L22 constitutes the second length, and the length L32 constitutes the third length.

[0041] A length L41 in the second direction D2 from the reference plane PL1 to the other end of the internal electrode 9 is shorter than the length L21. Therefore, when the internal electrode 9 that is not electrically connected to the internal electrode 7A and the second electrode layer E2 to which the internal electrode 7A is electrically connected are viewed from the third direction D3, the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected overlap each other. A length L42 in the second direction D2 from the reference plane PL2 to the other end of the internal electrode 7 is shorter than the length L22. Therefore, when the internal electrode 7 that is not electrically connected to the internal electrode 9A and the second electrode layer E2 to which the internal electrode 9A is electrically connected are viewed in the third direction D3, the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected overlap each other.

[0042] Lengths L11 and L12 may be the same or different. Lengths L21 and L22 may be the same or different. Lengths L31 and L32 may be the same or different. Lengths L41 and L42 may be the same or different.

[0043] When the multilayer capacitor C1 is solder-mounted on an electronic device, an external force acting on the multilayer capacitor C1 from the electronic device may be transmitted to the element body 3 through the electrode portions 5c. The external force is transmitted to the electrode portions 5c from solder fillets formed during solder mounting. The electronic device may include, for example, a circuit board or an electronic component. In the multilayer capacitor C1, the electrode portion 5c has the second electrode layer E2. Therefore, external force is unlikely to act from the electrode portion 5c to the element body 3. As a result, the multilayer capacitor C1 suppresses the occurrence of cracks in the element body 3.

[0044] In the multilayer capacitor C1, the lengths L11 and L12 are greater than the lengths L21 and L22. Therefore, the internal electrodes 7 and 9 adjacent to the internal electrodes 7A and 9A in the third direction D3 and the second electrode layer E2 included in the electrode portion 5c adjacent to the internal electrodes 7A and 9A in the third direction D3 are not electrically connected to each other, but are unlikely to face each other in the third direction D3. An electric field is unlikely to be generated between the second electrode layer E2 and the internal electrodes 7 and 9 that are not electrically connected to each other. The lengths L11 and L12 are shorter than the lengths L31 and L32. Therefore, the internal electrodes 7A and 9A are unlikely to face, in the third direction D3, the second electrode layer E2 included in the electrode portion 5c to which the internal electrodes 7A and 9A are not electrically connected. An electric field is unlikely to be generated between the second electrode layer E2 and the internal electrodes 7A and 9A, which are not electrically connected to each other. The electrode portion 5a does not include the second electrode layer E2. Therefore, the second electrode layer E2 and the internal electrodes 7, 9, which are not electrically connected to each other, do not face each other in the first direction D1. As a result, the multilayer capacitor C1 suppresses the occurrence of migration.

[0045] The multilayer capacitor C1 includes conductors 11 and 13. The conductor 11 is electrically connected to the external electrode 5 to which the internal electrode 7A is not electrically connected. The conductor 13 is electrically connected to the external electrode 5 to which the internal electrode 9A is not electrically connected. In a configuration in which the conductors 11 and 13 are located in the same layer as the internal electrodes 7A and 9A, structural defects are unlikely to occur in the element body 3.

[0046] In the multilayer capacitor C1, when the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected are viewed from the third direction D3, the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected overlap each other. When the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected are viewed from the third direction D3, the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected overlap each other. In this case, the length of the internal electrodes 7, 9 in the second direction D2 increases, and the capacitance of the multilayer capacitor C1 can be increased.

[0047] 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.

[0048] Next, the mounting structure of the multilayer capacitor C1 will be described with reference to Fig. 6 and Fig. 7. Fig. 6 and Fig. 7 are diagrams showing the mounting structure of the multilayer capacitor in accordance with this embodiment.

[0049] As shown in FIGS. 6 and 7, the electronic component device includes a multilayer capacitor C1 and an electronic device ED. The electronic device ED is, for example, a circuit board or an electronic component. The multilayer capacitor C1 is solder-mounted to the electronic device ED. The electronic device ED has a main surface EDa and two pad electrodes PE. Each pad electrode PE is arranged on the main surface EDa. The two pad electrodes PE are spaced apart from each other. The multilayer capacitor C1 is arranged on the electronic device ED so that the main surface 3a, which is the mounting surface, faces the main surface EDa. Each internal electrode 7, 9 is located in a plane approximately perpendicular to the main surface EDa.

[0050] When the multilayer capacitor C1 is solder-mounted, the molten solder wets and rises on the external electrodes 5 (third electrode layers E3). When the wetted solder solidifies, a solder fillet SF is formed on the external electrodes 5. The corresponding external electrodes 5 and pad electrodes PE are connected via the solder fillets SF.

[0051] Next, the configuration of a multilayer capacitor according to a modified example of this embodiment will be described with reference to Fig. 8. Fig. 8 is a diagram showing the cross-sectional configuration of the multilayer capacitor according to the modified example of this embodiment. The multilayer capacitor 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 above-described embodiment in the configuration of the electrode portion 5e. Below, the differences between the above-described embodiment and this modified example will be mainly described.

[0052] Each electrode portion 5e has a three-layer structure including a first electrode layer E1, a second electrode layer E2, and a third electrode layer E3. 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 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. 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. The second electrode layer E2 of each electrode unit 5c, 5e is integrally formed.

[0053] The configuration in which the electrode portion 5e has the second electrode layer E2 relieves stress acting on the solder fillet formed on the electrode portion 5e, and therefore the multilayer capacitor according to this modification suppresses the occurrence of solder cracks.

[0054] The above describes embodiments and modifications of the present invention, but the present invention is not necessarily limited to the above-described embodiments and modifications, and various modifications are possible without departing from the spirit of the present invention.

[0055] The multilayer capacitor C1 does not necessarily have to include the conductors 11 and 13, as shown in Fig. 9. When the multilayer capacitor C1 includes the conductors 11 and 13, structural defects are less likely to occur in the element body 3, as described above. Fig. 9 is a diagram showing a cross-sectional structure of a multilayer capacitor according to a modified example of this embodiment. In the modification shown in FIG. 9, the electrode portion 5e may have a second electrode layer E2, similarly to the modification shown in FIG.

[0056] When the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected are viewed from the third direction D3, the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected do not have to overlap each other. When the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected are viewed from the third direction D3, the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected do not have to overlap each other. When the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected are viewed from the third direction D3, the internal electrode 9 and the second electrode layer E2 to which the internal electrode 7A is electrically connected overlap each other, and when the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected are viewed from the third direction D3, the internal electrode 7 and the second electrode layer E2 to which the internal electrode 9A is electrically connected overlap each other, the capacitance of the multilayer capacitor C1 can be increased as described above.

[0057] In the present embodiment and the modified examples, the multilayer capacitor C1 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]

[0058] 3…body, 3a…principal surface, 3c…side surface, 3e…end surface, 5…external electrode, 5a, 5c, 5e…electrode portion, 7, 9, 7A, 9A…internal electrode, 7Ae1, 7Ae2, 9Ae1, 9Ae2…end of internal electrode, 11, 13…conductor, C1…layer conductor, D1…first direction, D2…second direction, D3…third direction, E1…first electrode layer, E2…second electrode layer, E2e…end edge of second electrode layer, E3…third electrode layer, PL1, PL2…reference plane.

Claims

1. an element body having a rectangular parallelepiped shape and including a pair of main surfaces facing each other in a first direction, a pair of end surfaces facing each other in a second direction, and a pair of side surfaces facing each other in a third direction; a plurality of external electrodes respectively disposed on both end portions of the element body in the second direction; a plurality of internal electrodes arranged in the element body so as to be aligned in the third direction and exposed on corresponding one of the pair of end faces, Each of the external electrodes is a pair of first electrode portions disposed on the pair of side surfaces, each of the first electrode portions including a conductive resin layer containing a plurality of silver particles and a plating layer formed so as to cover the conductive resin layer; a pair of second electrode portions disposed on the pair of main surfaces, the second electrode portions not including a conductive resin layer but including a plating layer; one of the two conductive resin layers located on the same side surface has an edge facing the other conductive resin layer; an outermost internal electrode located outermost in the third direction among the plurality of internal electrodes is adjacent to the first electrode portion to which the outermost internal electrode is electrically connected in the third direction; a first length of the outermost internal electrode in the second direction from the reference plane, the first length being greater than a second length from the reference plane to the edge of the conductive resin layer to which the outermost internal electrode is electrically connected, and the second length being less than a third length from the reference plane to the edge of the conductive resin layer to which the outermost internal electrode is not electrically connected.

2. 2. The electronic component according to claim 1, wherein each of the external electrodes further includes a third electrode portion disposed on the end face and including a conductive resin layer and a plating layer formed to cover the conductive resin layer.

3. a dummy conductor located in the same layer as the outermost internal electrode and spaced apart from the outermost internal electrode; 3. The electronic component according to claim 1, wherein the dummy conductor is electrically connected to the external electrode to which the outermost internal electrode located in the same layer as the dummy conductor is not electrically connected.

4. 4. The electronic component according to claim 1, wherein when the internal electrode that is not electrically connected to the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is electrically connected are viewed from the third direction, the internal electrode that is not electrically connected to the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is electrically connected overlap each other.

5. an element body having a rectangular parallelepiped shape and including a pair of main surfaces facing each other in a first direction, a pair of end surfaces facing each other in a second direction, and a pair of side surfaces facing each other in a third direction; a plurality of external electrodes respectively disposed on both end portions of the element body in the second direction; a plurality of internal electrodes arranged in the element body so as to be aligned in the third direction and exposed on corresponding one of the pair of end faces, Each of the external electrodes is a pair of first electrode portions disposed on the pair of side surfaces, each of the first electrode portions including a conductive resin layer containing a plurality of silver particles and a plating layer formed so as to cover the conductive resin layer; a pair of second electrode portions disposed on the pair of main surfaces, the second electrode portions not including a conductive resin layer but including a plating layer; Among the plurality of internal electrodes, an outermost internal electrode located outermost in the third direction is a first end exposed on the end surface; a second end facing the first end in the second direction and located within the element body, when the outermost internal electrode and the conductive resin layer to which the outermost internal electrode is electrically connected are viewed from the third direction, the second end is exposed from the conductive resin layer, an outermost internal electrode and the conductive resin layer to which the outermost internal electrode is not electrically connected, when viewed from the third direction, the outermost internal electrode and the conductive resin layer do not overlap each other.

6. Each of the external electrodes further includes a third electrode portion disposed on the end surface, The electronic component according to claim 1 or 5, wherein the third electrode portion includes a base metal layer formed on the end surface and connected to a corresponding one of the plurality of internal electrodes, and a conductive resin layer arranged on the end surface so as to cover the base metal layer.

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