Electronic component

Abstract

To provide an electronic component that suppresses occurrence of Ag migration.SOLUTION: A multilayer capacitor C1 includes an element body 3 and an external electrode 5. The external electrode 5 is disposed on the element body 3. The external electrode 5 includes a second electrode layer E2 including a plurality of Ag particles 13, and a metal plating layer PL disposed on the outside of the second electrode layer E2 with a gap between it and the element body 3. The metal plating layer PL includes a third electrode layer E3. The multilayer capacitor C1 includes an oxide 15 of a metal component contained in the third electrode layer E3. The oxide 15 is in contact with an end of the third electrode layer E3 and the element body 3, and is disposed in the gap between the third electrode layer E3 and the element body 3.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] The known electronic component includes an element body and external electrodes disposed on the element body. The external electrodes include, for example, a conductive resin layer and a metal plating layer located on the outer side of the conductive resin layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-144665 Summary of the Invention [Problem to be solved by the invention]

[0004] The conductive resin layer contains, for example, a plurality of Ag particles and a resin. In this case, there is a risk of Ag migration occurring in the external electrodes. The Ag migration is believed to occur, for example, due to the following phenomenon. An electric field or heat acts on the Ag particles contained in the conductive resin layer, causing the Ag particles to ionize. The Ag particles contained in the conductive resin layer may also be ionized under the influence of oxygen. The generated Ag ions are attracted to the electric field generated between the external electrodes and move from the conductive resin layer. The electric field acting on the Ag particles includes, for example, an electric field generated between the external electrodes, or an electric field generated between the external electrodes and an internal conductor disposed in the element. The Ag ions that move from the conductive resin layer react with electrons supplied from, for example, the internal conductor or the external electrode, and are precipitated as Ag on the surface of the element.

[0005] An object of one embodiment of the present invention is to provide an electronic component that suppresses the growth of Ag migration. [Means for solving the problem]

[0006] An electronic component according to one embodiment of the present invention includes an element body and an external electrode. The external electrode is disposed on the element body, and includes a conductive resin layer including a plurality of Ag particles and a metal plating layer disposed outside the conductive resin layer with a gap between the element body and the conductive resin layer. The electronic component according to the above embodiment includes an oxide of a metal component contained in the metal plating layer. The oxide is disposed in the gap between the metal plating layer and the element body, in contact with an end of the metal plating layer and the element body.

[0007] In the above-mentioned embodiment, the oxide is disposed in the gap between the metal plating layer and the element body, in contact with the edge of the metal plating layer and the element body. Therefore, even if Ag migration occurs in the conductive resin layer, the growth of the Ag migration is suppressed. The above-mentioned embodiment suppresses the growth of Ag migration on the element body 3. The oxide disposed in the gap between the metal plating layer and the element body, in contact with the edge of the metal plating layer and the element body, is an oxide of a metal component contained in the metal plating layer. Therefore, the above-mentioned one embodiment reliably disposes the oxide in the gap between the metal plating layer and the element body.

[0008] The above-mentioned one aspect may include the following configuration: In this configuration, the metal plating layer includes a Cu plating layer, and the oxide includes an oxide of Cu contained in the Cu plating layer. In a configuration in which the oxide includes an oxide of Cu contained in the Cu plating layer, for example, the oxide can be formed by heat treating the Cu plating layer, and therefore the oxide can be easily arranged.

[0009] The above-mentioned one aspect may include the following configuration: In this configuration, the metal plating layer includes a metal plating layer separate from the Cu plating layer, the metal plating layer being disposed outside the Cu plating layer with a gap between the metal plating layer and the base body. In a configuration in which the metal plating layer includes the another metal plating layer, the another metal plating layer has a gap between it and the base body. For example, when the Cu plating layer is heat-treated, heat is likely to act on the Cu plating layer through the gap between the another metal plating layer and the base body. Therefore, even in a configuration in which the metal plating layer includes the another metal plating layer, oxides can be easily and reliably arranged.

[0010] The above-mentioned one aspect may include the following configuration: In this configuration, the metal plating layer separate from the Cu plating layer includes a Ni plating layer. The metal plating layer including the Ni plating layer prevents solder leaching during solder mounting.

[0011] The above-mentioned one aspect may include the following configuration: In this configuration, the metal plating layer separate from the Cu plating layer includes a solder plating layer disposed on the outside of the Ni plating layer. The metal plating layer including the solder plating layer improves solder mountability.

[0012] The above-mentioned one aspect may include the following configuration: In this configuration, the solder plating layer has a gap between it and the element body. The solder plating layer has a gap between it and the element body. For example, when the Cu plating layer is heat-treated, heat is likely to act on the Cu plating layer through the gap between the solder plating layer and the element body. Therefore, even in a configuration in which the metal plating layer includes a solder plating layer, oxides can be easily and reliably arranged.

[0013] The above aspect may include the following configuration: In this configuration, the oxide extends along the edge of the conductive resin layer. The structure in which the oxide extends along the edge of the conductive resin layer reliably suppresses the growth of migration of Ag. Effect of the Invention

[0014] One embodiment of the present invention provides an electronic component that suppresses the growth of Ag migration. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view of a multilayer capacitor in accordance with one embodiment. [Diagram 2] FIG. 2 is a diagram showing a cross-sectional structure of the multilayer capacitor in accordance with this embodiment. [Diagram 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 configuration of an external electrode. [Diagram 5] FIG. 5 is a diagram showing a cross-sectional configuration of an external electrode. [Figure 6] FIG. 6 is a plan view showing the second electrode layer and the oxide. [Figure 7] FIG. 7 is a plan view showing the second electrode layer and the oxide. [Figure 8] FIG. 8 is a diagram showing a cross-sectional configuration of an external electrode. [Figure 9] FIG. 9 is a diagram showing a cross-sectional configuration of an external electrode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment 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 duplicated description will be omitted.

[0017] The configuration of the multilayer capacitor C1 in accordance with this embodiment will be described with reference to Figs. 1 to 7. Fig. 1 is a perspective view of the multilayer capacitor in accordance with this embodiment. Figs. 2 and 3 are diagrams showing a cross-sectional configuration of the multilayer capacitor in accordance with this embodiment. Figs. 4 and 5 are diagrams showing cross-sectional configurations of external electrodes. Figs. 6 and 7 are plan views showing second electrode layers and oxides. In this embodiment, the electronic component is, for example, a multilayer capacitor C1.

[0018] 1, the multilayer capacitor C1 includes a rectangular parallelepiped-shaped element body 3 and a plurality of external electrodes 5. The multilayer capacitor C1 includes, for example, 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 edges, and a rectangular parallelepiped shape with rounded corners and edges.

[0019] The element body 3 includes 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 direction D2. The direction in which the pair of side surfaces 3c face each other is direction D3. The direction in which the pair of end surfaces 3e face each other is direction D1. The multilayer capacitor C1 is solder-mounted on an electronic device. The electronic device includes, for example, a circuit board or another electronic component. In the multilayer capacitor C1, one of the four side surfaces 3a, 3c faces the electronic device. One of the four side surfaces 3a, 3c is disposed so as to form a mounting surface. One of the four side surfaces 3a, 3c is the mounting surface. For example, the side surface 3a is the mounting surface.

[0020] The direction D2 is a direction perpendicular to each side surface 3a and perpendicular to the direction D3. The direction D1 is a direction parallel to each side surface 3a and each side surface 3c and perpendicular to the directions D2 and D3. The direction D3 is a direction perpendicular to each side surface 3c, and the direction D1 is a direction perpendicular to each end surface 3e. The length of the element body 3 in the direction D1 is, for example, greater than the length of the element body 3 in the direction D2 and greater than the length of the element body 3 in the direction D3. The direction D1 is the longitudinal direction of the element body 3. The length of the element body 3 in the direction D2 and the length of the element body 3 in the direction D3 may be equal to each other. The length of the element body 3 in the direction D2 and the length of the element body 3 in the direction D3 may be different from each other.

[0021] The length of element body 3 in direction D2 is the height of element body 3. The length of element body 3 in direction D3 is the width of element body 3. The length of element body 3 in direction D1 is the length of element body 3. For example, the height of element body 3 is 0.1 to 3.2 mm, the width of element body 3 is 0.1 to 6.3 mm, and the length of element body 3 is 0.2 to 7.5 mm. For example, the height of element body 3 is 2.5 mm, the width of element body 3 is 2.5 mm, and the length of element body 3 is 3.2 mm.

[0022] The pair of side surfaces 3a extend in direction D3 to connect the pair of side surfaces 3c. The pair of side surfaces 3a also extend in direction D1. The pair of side surfaces 3c extend in direction D2 to connect the pair of side surfaces 3a. The pair of side surfaces 3c also extend in direction D1. The pair of end faces 3e extend in direction D2 to connect the pair of side surfaces 3a. The pair of end faces 3e extend in direction D3 to connect the pair of side surfaces 3c.

[0023] The element body 3 includes a ridge portion located between the end face 3e and the side face 3a, a ridge portion located between the end face 3e and the side face 3c, and a ridge portion located between the side face 3a and the side face 3c. For example, each ridge portion is 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 through the ridge portion located between the end face 3e and the side face 3a. The end face 3e and the side face 3c are indirectly adjacent to each other through the ridge portion located between the end face 3e and the side face 3c. The side face 3a and the side face 3c are indirectly adjacent to each other through the ridge portion located between the side face 3a and the side face 3c.

[0024] The element body 3 is configured by stacking a plurality of dielectric layers in the direction D2. The element body 3 includes a plurality of dielectric layers that are stacked. In the element body 3, the stacking direction of the plurality of dielectric layers coincides with the direction D2. Each dielectric layer is configured, for example, from a sintered body of a ceramic green sheet including 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 such an extent that the boundaries between the dielectric layers are not visible.

[0025] As shown in Figs. 2 and 3, the multilayer capacitor C1 includes a plurality of internal electrodes 7. Each internal electrode 7 is an internal conductor disposed within the element body 3. Each internal electrode 7 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 electrode 7 is configured as a sintered body of a conductive paste that includes the conductive material. For example, the internal electrode 7 is made of Ni.

[0026] The internal electrodes 7 are arranged at different positions (layers) in the direction D2. The internal electrodes 7 are arranged in the element body 3 so as to face each other with a gap in the direction D2. The internal electrodes 7 adjacent to each other in the direction D2 have different polarities. One end of the internal electrode 7 is exposed at a corresponding end face 3e of the pair of end faces 3e. The internal electrodes 7 include one end exposed at the corresponding end face 3e. The internal electrodes 7 include an internal electrode 7 exposed at one end face 3e of the pair of end faces 3e and an internal electrode 7 exposed at the other end face 3e of the pair of end faces 3e. The internal electrodes 7 exposed at one end face 3e and the internal electrodes 7 exposed at the other end face 3e are alternately arranged in the direction D2. The internal electrodes 7 are arranged in the element body 3 so as to be aligned in the direction D2. The internal electrodes 7 are located in a plane substantially parallel to the side face 3a. The direction in which the internal electrodes 7 face each other (direction D2) is perpendicular to the directions (directions D3 and D1) parallel to the side surface 3a.

[0027] When the lamination direction of the multiple dielectric layers is direction D3, the multiple internal electrodes 7 are arranged at different positions (layers) in direction D3. When the lamination direction of the multiple dielectric layers is direction D3, the internal electrodes 7 exposed at one end face 3e and the internal electrodes 7 exposed at the other end face 3e are arranged alternately in direction D3. The internal electrodes 7 are located in a plane approximately parallel to the side face 3c. The internal electrodes 7 face each other in direction D3.

[0028] The external electrodes 5 are arranged at both ends of the element body 3 in the direction D1, as shown in FIG. 1. Each external electrode 5 is arranged on the side of the corresponding end face 3e of the element body 3. For example, each external electrode 5 is arranged on a pair of side faces 3a, a pair of side faces 3c, and one end face 3e. The external electrode 5 includes a plurality of electrode portions 5a, 5c, and 5e, as shown in FIG. 2 and FIG. 3. The electrode portion 5a is located on the side face 3a and on the ridge between the side face 3a and the end face 3e. The electrode portion 5c is located on the side face 3c and on the ridge between the side face 3c and the end face 3e. The electrode portion 5e is located on the end face 3e. The external electrode 5 also includes an electrode portion located on the ridge between the side face 3a and the side face 3c.

[0029] The external electrode 5 is formed on five faces, namely the four side faces 3a, 3c and one end face 3e, as well as on the ridge portion. The adjacent electrode portions 5a, 5c, 5e are physically linked and electrically connected. The electrode portion 5e covers an end of a corresponding one of the multiple internal electrodes 7. The electrode portion 5e is directly connected to the corresponding internal electrode 7. The external electrode 5 is electrically connected to the corresponding internal electrode 7. 2 to 5, the external electrode 5 includes a first electrode layer E1, a second electrode layer E2, a third electrode layer E3, a fourth electrode layer E4, and a fifth electrode layer E5. The fifth electrode layer E5 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, a third electrode layer E3, a fourth electrode layer E4, and a fifth electrode layer E5.

[0030] The first electrode layer E1 of the electrode portion 5a is disposed on the ridge between the side surface 3a and the end surface 3e, and is not disposed on the side surface 3a. The first electrode layer E1 of the electrode portion 5a covers the entire ridge between the side surface 3a and the end surface 3e. The first electrode layer E1 does not cover the side surface 3a. The first electrode layer E1 of the electrode portion 5a is in contact with the ridge between the side surface 3a and the end surface 3e. The side surface 3a is exposed from the first electrode layer E1. The first electrode layer E1 of the electrode portion 5a may be disposed on the side surface 3a. In this case, the first electrode layer E1 of the electrode portion 5a covers a partial area of ​​the side surface 3a and the entire ridge portion 3g. That is, the first electrode layer E1 of the electrode portion 5a is in contact with the partial area of ​​the side surface 3a. The partial area covered by the first electrode layer E1 of the electrode portion 5a is located closer to the end surface 3e. The second electrode layer E2 of the electrode portion 5a is disposed on the first electrode layer E1 and the side surface 3a. In the electrode portion 5a, the second electrode layer E2 covers the entire first electrode layer E1 and also covers a partial area of ​​the side surface 3a. The second electrode layer E2 of the electrode portion 5a indirectly covers the ridge between the side surface 3a and the end surface 3e so that the first electrode layer E1 is located between the second electrode layer E2 and the element body 3. In the electrode portion 5a, the second electrode layer E2 is in direct contact with the first electrode layer E1. The partial area covered by the second electrode layer E2 of the electrode portion 5a is located closer to the end surface 3e. The side surface 3a is exposed from the second electrode layer E2 in the remaining part except for the partial area covered by the second electrode layer E2. In the electrode portion 5a, the second electrode layer E2 is in direct contact with the side surface 3a. In the electrode portion 5a, the second electrode layer E2 directly covers the side surface 3a. The second electrode layer E2 of the electrode portion 5a is located on the side surface 3a and on the ridge between the side surface 3a and the end surface 3e.

[0031] The third electrode layer E3 of the electrode portion 5a is disposed on the second electrode layer E2. In the electrode portion 5a, the third electrode layer E3 covers the second electrode layer E2. In the electrode portion 5a, the third electrode layer E3 is in contact with the second electrode layer E2. That is, in the electrode portion 5a, the third electrode layer E3 is in direct contact with the second electrode layer E2. The fourth electrode layer E4 of the electrode portion 5a is disposed on the third electrode layer E3. In the electrode portion 5a, the fourth electrode layer E4 covers the third electrode layer E3. In the electrode portion 5a, the fourth electrode layer E4 is in contact with the third electrode layer E3. That is, in the electrode portion 5a, the fourth electrode layer E4 is in direct contact with the third electrode layer E3. The fifth electrode layer E5 of the electrode portion 5a is disposed on the fourth electrode layer E4. In the electrode portion 5a, the fifth electrode layer E5 covers the fourth electrode layer E4. In the electrode portion 5a, the fifth electrode layer E5 is in contact with the fourth electrode layer E4. That is, in the electrode portion 5a, the fifth electrode layer E5 is in direct contact with the fourth electrode layer E4. In the electrode portion 5a, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are not in contact with the side surface 3a. In the electrode portion 5a, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are arranged outside the second electrode layer E2 with a gap between them and the side surface 3a. The fourth electrode layer E4 of the electrode portion 5a is arranged outside the third electrode layer E3 of the electrode portion 5a. The fifth electrode layer E5 of the electrode portion 5a is arranged outside the fourth electrode layer E4 of the electrode portion 5a. The third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 of the electrode portion 5a are located on the side surface 3a.

[0032] The first electrode layer E1 of the electrode portion 5c is disposed on the ridge between the side surface 3c and the end surface 3e, but is not disposed on the side surface 3c. The first electrode layer E1 of the electrode portion 5c covers the entire ridge between the side surface 3c and the end surface 3e. The first electrode layer E1 does not cover the side surface 3c. The first electrode layer E1 of the electrode portion 5c contacts the ridge between the side surface 3c and the end surface 3e. The side surface 3c is exposed from the first electrode layer E1. The first electrode layer E1 of the electrode portion 5c may be disposed on the side surface 3c. In this case, the first electrode layer E1 of the electrode portion 5c covers a partial area of ​​the side surface 3c and the entire ridge portion 3g. That is, the first electrode layer E1 of the electrode portion 5c contacts the partial area of ​​the side surface 3c. The partial area covered by the first electrode layer E1 of the electrode portion 5c is located closer to the end surface 3e. 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 covers the entire first electrode layer E1 and also covers a partial area of ​​the side surface 3c. The second electrode layer E2 of the electrode portion 5c indirectly covers the ridge between the side surface 3c and the end surface 3e so that the first electrode layer E1 is located between the second electrode layer E2 and the element body 3. In the electrode portion 5c, the second electrode layer E2 is in direct contact with the first electrode layer E1. The partial area covered by the second electrode layer E2 of the electrode portion 5c is located closer to the end surface 3e. The remaining part of the side surface 3c is exposed from the second electrode layer E2 except for the partial area covered by the second electrode layer E2. In the electrode portion 5c, the second electrode layer E2 is in direct contact with the side surface 3c. In the electrode portion 5c, the second electrode layer E2 directly covers the side surface 3c. The second electrode layer E2 of the electrode portion 5c is located on the side surface 3c and on the ridge between the side surface 3c and the end surface 3e.

[0033] The third electrode layer E3 of the electrode portion 5c is disposed on the second electrode layer E2. In the electrode portion 5c, the third electrode layer E3 covers the second electrode layer E2. In the electrode portion 5c, the third electrode layer E3 is in contact with the second electrode layer E2. That is, in the electrode portion 5c, the third electrode layer E3 is in direct contact with the second electrode layer E2. The fourth electrode layer E4 of the electrode portion 5c is disposed on the third electrode layer E3. In the electrode portion 5c, the fourth electrode layer E4 covers the third electrode layer E3. In the electrode portion 5c, the fourth electrode layer E4 is in contact with the third electrode layer E3. That is, in the electrode portion 5c, the fourth electrode layer E4 is in direct contact with the third electrode layer E3. The fifth electrode layer E5 of the electrode portion 5c is disposed on the fourth electrode layer E4. In the electrode portion 5c, the fifth electrode layer E5 covers the fourth electrode layer E4. In the electrode portion 5c, the fifth electrode layer E5 is in contact with the fourth electrode layer E4. That is, in the electrode portion 5c, the fifth electrode layer E5 is in direct contact with the fourth electrode layer E4. In the electrode portion 5c, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are not in contact with the side surface 3c. In the electrode portion 5c, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are arranged outside the second electrode layer E2 with a gap between them and the side surface 3c. The fourth electrode layer E4 of the electrode portion 5c is arranged outside the third electrode layer E3 of the electrode portion 5c. The fifth electrode layer E5 of the electrode portion 5c is arranged outside the fourth electrode layer E4 of the electrode portion 5c. The third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 of the electrode portion 5c are located on the side surface 3c.

[0034] The second electrode layer E2 of the electrode portion 5c may cover only a partial area of ​​the ridge between the side surface 3c and the end surface 3e and only a partial area of ​​the side surface 3c. The partial area of ​​the ridge between the side surface 3c and the end surface 3e is located, for example, closer to the side surface 3a. The partial area of ​​the side surface 3c is located, for example, closer to a corner closer to the side surface 3a and the end surface 3e. In this case, the electrode portion 5c may have the following configuration. The second electrode layer E2 of the electrode portion 5c indirectly covers the partial area of ​​the ridge between the side surface 3c and the end surface 3e such that the first electrode layer E1 is located between the second electrode layer E2 and the ridge between the side surface 3c and the end surface 3e. The second electrode layer E2 of the electrode portion 5c directly covers the partial area of ​​the side surface 3c. The second electrode layer E2 of the electrode portion 5c directly covers a partial area of ​​the portion of the first electrode layer E1 located on the ridge between the side surface 3c and the end surface 3e. The electrode portion 5c includes a region where the first electrode layer E1 is exposed from the second electrode layer E2, and a region where the first electrode layer E1 is covered with the second electrode layer E2.

[0035] The first electrode layer E1 of the electrode portion 5e is disposed on the end surface 3e. The first electrode layer E1 of the electrode portion 5e covers the entire end surface 3e. The first electrode layer E1 of the electrode portion 5e is in contact with the entire end surface 3e. That is, in the electrode portion 5e, the first electrode layer E1 is in direct contact with the end surface 3e. The second electrode layer E2 of the electrode portion 5e is disposed on the first electrode layer E1. In the electrode portion 5e, the second electrode layer E2 covers the first electrode layer E1. In the electrode portion 5e, the second electrode layer E2 is in direct contact with the first electrode layer E1. In the electrode portion 5e, the second electrode layer E2 indirectly covers the end surface 3e such that the first electrode layer E1 is located between the second electrode layer E2 and the end surface 3e. The second electrode layer E2 of the electrode portion 5e is located on the end surface 3e.

[0036] The third electrode layer E3 of the electrode portion 5e is disposed on the second electrode layer E2. In the electrode portion 5e, the third electrode layer E3 covers the second electrode layer E2. In the electrode portion 5e, the third electrode layer E3 is in contact with the second electrode layer E2. That is, in the electrode portion 5e, the third electrode layer E3 is in direct contact with the second electrode layer E2. In the electrode portion 5e, the third electrode layer E3 is not in direct contact with the first electrode layer E1. The fourth electrode layer E4 of the electrode portion 5e is disposed on the third electrode layer E3. In the electrode portion 5e, the fourth electrode layer E4 covers the third electrode layer E3. In the electrode portion 5e, the fourth electrode layer E4 is in contact with the third electrode layer E3. That is, in the electrode portion 5e, the fourth electrode layer E4 is in direct contact with the third electrode layer E3. The fifth electrode layer E5 of the electrode portion 5e is disposed on the fourth electrode layer E4. In the electrode portion 5e, the fifth electrode layer E5 covers the fourth electrode layer E4. In the electrode portion 5e, the fifth electrode layer E5 is in contact with the fourth electrode layer E4. That is, in the electrode portion 5e, the fifth electrode layer E5 is in direct contact with the fourth electrode layer E4. In the electrode portion 5e, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are disposed outside the second electrode layer E2. The fourth electrode layer E4 of the electrode portion 5e is disposed outside the third electrode layer E3 of the electrode portion 5e. The fifth electrode layer E5 of the electrode portion 5e is disposed outside the fourth electrode layer E4 of the electrode portion 5e. The third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 of the electrode portion 5e are located on the end surface 3e.

[0037] The second electrode layer E2 of the electrode portion 5e may cover only a part of the area of ​​the end face 3e. The part of the area of ​​the end face 3e is located, for example, closer to the side face 3a. In this case, the electrode portion 5e may have the following configuration. The second electrode layer E2 of the electrode portion 5e indirectly covers the part of the area of ​​the end face 3e such 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 portion 5e directly covers only a part of the area of ​​the first electrode layer E1 located on the end face 3e. That is, the electrode portion 5e includes an area where the first electrode layer E1 is exposed from the second electrode layer E2 and an area where the first electrode layer E1 is covered by the second electrode layer E2.

[0038] The first electrode layer E1 is formed by baking a conductive paste applied to the surface of the element body 3. The conductive paste is applied to one end face 3e, the ridge between the side face 3a and the end face 3e, and the ridge between the side face 3c and the end face 3e. The first electrode layer E1 is formed so as to cover one end face 3e, the ridge between the side face 3a and the end face 3e, and the ridge between the side face 3c and the end face 3e. The first electrode layer E1 is formed by sintering a metal component (metal powder) 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 the multilayer capacitor C1, the first electrode layer E1 is a sintered metal layer made of Cu. The first electrode layer E1 may be a sintered metal layer made of Ni. The first electrode layer E1 includes a base metal. The conductive paste includes, for example, a powder made of Cu or Ni, a glass component, an organic binder, and an organic solvent. The first electrode layer E1 of each of the electrode portions 5a, 5c, and 5e is integrally formed.

[0039] The second electrode layer E2 is formed by hardening a conductive resin paste applied onto the first electrode layer E1. The conductive resin paste is applied onto the first electrode layer E1 and onto a partial area of ​​each of the side surfaces 3a and 3c. The second electrode layer E2 is formed over the first electrode layer E1 and the element body 3. The conductive resin paste includes, for example, a plurality of Ag particles, a resin, and an organic solvent. The resin is, for example, a thermosetting resin. The thermosetting resin is, for example, a phenol resin, an acrylic resin, a silicone resin, an epoxy resin, or a polyimide resin. The second electrode layer E2 is in contact with a part of the ridge between the side surface 3a and the side surface 3c. The second electrode layer E2 of each electrode portion 5a, 5c, 5e is integrally formed. The second electrode layer E2 is a conductive resin layer covering the first electrode layer E1. As shown in Figs. 4 and 5, the second electrode layer E2 includes a resin 11 and a plurality of Ag particles 13. The plurality of Ag particles 13 form a conductive path in the second electrode layer E2. Figs. 8 and 9 show a schematic cross-sectional configuration of the external electrode 5. Hatching showing a cross section is omitted in Figs. 4 and 5. The shape and size of the Ag particles 13 shown in Figs. 4 and 5 differ from the shape and size of the actual Ag particles.

[0040] The third electrode layer E3 is formed on the second electrode layer E2 by a plating method. In the multilayer capacitor C1, the third electrode layer E3 is formed on the second electrode layer E2 by Cu plating. The third electrode layer E3 is a Cu plating layer. The third electrode layer E3 includes Cu. The third electrode layer E3 is not limited to Cu, and may include a metal that expands in volume by oxidation. The third electrode layer E3 covers the second electrode layer E2. The fourth electrode layer E4 is formed on the third electrode layer E3 by a plating method. In the multilayer capacitor C1, the fourth electrode layer E4 is formed on the third electrode layer E3 by Ni plating. The fourth electrode layer E4 is a Ni plating layer. The fourth electrode layer E4 contains Ni. The Ni plating layer has better solder leach resistance than the Ag particles 13 contained in the second electrode layer E2. The third electrode layer E3 covers the second electrode layer E2. The fifth electrode layer E5 is formed on the fourth electrode layer E4 by a plating method. The fifth electrode layer E5 is a solder plating layer. In the multilayer capacitor C1, the fifth electrode layer E5 is formed on the fourth electrode layer E4 by Sn plating. The fifth electrode layer E5 is a Sn plating layer. The fifth electrode layer E5 contains Sn. The fifth electrode layer E5 may be a Sn-Ag alloy plating layer, a Sn-Bi alloy plating layer, or a Sn-Cu alloy plating layer.

[0041] The third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 constitute a metal plating layer PL formed on the second electrode layer E2. That is, the external electrode 5 includes a metal plating layer PL, which includes the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5. The metal plating layer PL covers the second electrode layer E2. The third electrode layer E3 included in each electrode portion 5a, 5c, and 5e is integrally formed. The fourth electrode layer E4 included in each electrode portion 5a, 5c, and 5e is integrally formed. The fifth electrode layer E5 included in each electrode portion 5a, 5c, and 5e is integrally formed.

[0042] The metal plating layer PL covering the second electrode layer E2 is easy to adhere to the second electrode layer E2, but is difficult to adhere to the element body 3. Therefore, the above-mentioned gap exists between the ends of the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 and the side surfaces 3a and 3c. A gap also exists between the ends of the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 and the ridge between the side surfaces 3a and 3c. The distance between the ends of the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 and the side surfaces 3a and 3c, i.e., the width of the above-mentioned gap, is, for example, greater than 0 and 3 μm or less. The width of the gap existing between the ends of the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 and the ridge between the side surfaces 3a and 3c is, for example, greater than 0 and 3 μm or less. The width of the above-mentioned gap may be different for the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5, and may be different for each of the side surfaces 3a, 3c, and the ridge between the side surfaces 3a and 3c.

[0043] As shown in Figs. 4 and 5, the multilayer capacitor C1 includes an oxide 15. The oxide 15 is in contact with an end of the third electrode layer E3 and the element body 3 and is disposed in the gap between the third electrode layer E3 and the element body 3. The oxide 15 fills the gap between the third electrode layer E3 and the element body 3. The thickness of the oxide 15 is equal to the distance between the third electrode layer E3 and the element body 3. The width of the oxide 15 is equal to the thickness of the third electrode layer E3, for example. The oxide 15 includes a portion 15a and a portion 15c. The oxide 15 constitutes, for example, an insulating layer. The portion 15a is located on the side surface 3a. The portion 15a is in contact with the end of the third electrode layer E3 and the side surface 3a, and is disposed in the gap that exists between the end of the third electrode layer E3 and the side surface 3a. The portion 15a fills the gap that exists between the end of the third electrode layer E3 and the side surface 3a. The portion 15c is located on the side surface 3c. The portion 15c is in contact with an end of the third electrode layer E3 and the side surface 3c, and is disposed in a gap that exists between the end of the third electrode layer E3 and the side surface 3c. The portion 15c fills the gap that exists between the end of the third electrode layer E3 and the side surface 3c. The oxide 15 includes a portion located on the ridge between the side 3a and the side 3c. This portion is in contact with the end of the third electrode layer E3 and the ridge between the side 3a and the side 3c, and is disposed in the gap between the end of the third electrode layer E3 and the ridge between the side 3a and the side 3c. The portion located on the ridge between the side 3a and the side 3c fills the gap between the end of the third electrode layer E3 and the ridge between the side 3a and the side 3c. The portion 15a, the portion 15c, and the portion located on the ridge between the side surface 3a and the side surface 3c are continuous and integrally formed. The oxide 15 is disposed across the pair of side surfaces 3a and the pair of side surfaces 3c.

[0044] As shown in Fig. 6, the portion 15a extends along the edge of the second electrode layer E2 of the electrode portion 5a. For example, the portion 15a extends continuously along the edge of the second electrode layer E2 of the electrode portion 5a. The portion 15a may be in contact with the second electrode layer E2 of the electrode portion 5a, or may be separated from the second electrode layer E2 of the electrode portion 5a. 7, the portion 15c extends along the edge of the second electrode layer E2 of the electrode portion 5c. For example, the portion 15c extends continuously along the edge of the second electrode layer E2 of the electrode portion 5c. The portion 15c may be in contact with the second electrode layer E2 of the electrode portion 5c, or may be separated from the second electrode layer E2 of the electrode portion 5c. The portion located on the ridge between the side 3a and the side 3c extends along the edge of the second electrode layer E2 included in the electrode portion located on the ridge between the side 3a and the side 3c. For example, the portion located on the ridge between the side 3a and the side 3c extends continuously along the edge of the second electrode layer E2 included in the electrode portion located on the ridge between the side 3a and the side 3c. The portion located on the ridge between the side 3a and the side 3c may be in contact with the second electrode layer E2 included in the electrode portion located on the ridge between the side 3a and the side 3c, or may be separated from the second electrode layer E2 included in the electrode portion located on the ridge between the side 3a and the side 3c. 6 and 7 are plan views showing the second electrode layer and the oxide.

[0045] The oxide 15 includes an oxide of a metal component included in the metal plating layer PL. In the multilayer capacitor C1, the oxide 15 includes an oxide of Cu included in the third electrode layer E3. For example, the oxide 15 is made of a Cu oxide. The oxide 15 is formed, for example, by heat treatment of the third electrode layer E3. In the heat treatment of the third electrode layer E3, for example, the following process proceeds. An oxide of Cu contained in the third electrode layer E3 is generated on the surface of the end of the third electrode layer E3. The Cu oxide generated on the surface of the end of the third electrode layer E3 grows toward the element body 3 in a gap between the end of the third electrode layer E3 and the element body 3. The Cu oxide grown in the gap between the end of the third electrode layer E3 and the element body 3 grows until it comes into contact with the element body 3. Conditions for the heat treatment of the third electrode layer E3 include, for example, a heating temperature or a heating time.

[0046] The heat treatment of the third electrode layer E3 may be performed after the fourth electrode layer E4 is formed and before the fifth electrode layer E5 is formed. In this case, an oxide of Ni contained in the fourth electrode layer E4 may be generated on the surface of the edge of the fourth electrode layer E4. Ni oxide tends to form a passive film and is more difficult to grow than Cu oxide. Therefore, a gap tends to exist between the fourth electrode layer E4 and the element body 3. The heat treatment of the third electrode layer E3 may be performed after the fifth electrode layer E5 is formed. In this case, an oxide of a metal contained in the fifth electrode layer E5, for example, an oxide of Sn, may be generated on the surface of the edge of the fifth electrode layer E5. Sn oxide tends to form a passive film and is more difficult to grow than Cu oxide. Therefore, a gap tends to exist between the fifth electrode layer E5 and the element body 3.

[0047] In the multilayer capacitor C1, the oxide 15 is disposed in the gap between the metal plating layer PL and the element body 3, in contact with the end of the metal plating layer PL and the element body 3. Therefore, even if Ag migration occurs in the second electrode layer E2, the growth of the Ag migration is suppressed. The multilayer capacitor C1 suppresses the growth of Ag migration on the element body 3. The oxide 15 includes an oxide of a metal component contained in the metal plating layer PL. Therefore, in the multilayer capacitor C1, the oxide 15 is reliably disposed in the gap between the metal plating layer PL and the element body 3.

[0048] In the multilayer capacitor C1, the metal plating layer PL includes a third electrode layer E3. The oxide 15 includes an oxide of Cu contained in the third electrode layer E3. In the multilayer capacitor C1, for example, the oxide 15 can be formed by heat treating the third electrode layer E3. Therefore, the oxide 15 can be easily arranged.

[0049] In the multilayer capacitor C1, the metal plating layer PL includes a fourth electrode layer E4. The fourth electrode layer E4 is a metal plating layer separate from the third electrode layer E3. The fourth electrode layer E4 has a gap between it and the element body 3. For example, when the third electrode layer E3 is heat-treated, heat is likely to act on the third electrode layer E3 through the gap between the fourth electrode layer E4 and the element body 3. Therefore, even in a configuration in which the metal plating layer PL includes the fourth electrode layer E4, the oxide 15 can be easily and reliably disposed.

[0050] In the multilayer capacitor C1, the metal plating layer PL includes a fourth electrode layer E4, which prevents solder leaching during solder mounting.

[0051] In the multilayer capacitor C1, the metal plating layer PL includes a fifth electrode layer E5. The fifth electrode layer E5 improves the solder mountability of the multilayer capacitor C1.

[0052] In the multilayer capacitor C1, the metal plating layer PL includes a fifth electrode layer E5. The fifth electrode layer E5 is a metal plating layer separate from the third electrode layer E3. The fifth electrode layer E5 has a gap between it and the element body 3. For example, when the third electrode layer E3 is heat-treated, heat is likely to act on the third electrode layer E3 through the gap between the fifth electrode layer E5 and the element body 3. Therefore, even in a configuration in which the metal plating layer PL includes the fifth electrode layer E5, the oxide 15 can be easily and reliably disposed.

[0053] 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 another element, an intervening element is present between the element and the other element. When an element directly covers another element, an intervening element is not present between the element and the other element.

[0054] In the multilayer capacitor C1, the oxide 15 extends along the edge of the second electrode layer E2. Therefore, the multilayer capacitor C1 reliably suppresses the growth of Ag migration.

[0055] Although the embodiment of the present invention has been described above, the present invention is not necessarily limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention.

[0056] The metal plating layer PL may include a sixth electrode layer E6 located between the second electrode layer E2 and the third electrode layer E3, as shown in Fig. 8 and Fig. 9. That is, the electrode portions 5a, 5c and the electrode portion located on the ridge between the side surfaces may include the sixth electrode layer E6. Fig. 8 and Fig. 9 are diagrams showing the cross-sectional configuration of the external electrode. In Fig. 8 and Fig. 9, the cross-sectional configuration of the external electrode 5 is shown typically. In Fig. 8 and Fig. 9, hatching showing a cross section is omitted. The shape and size of the Ag particles 13 shown in Fig. 8 and Fig. 9 are different from the shape and size of the actual Ag particles. In a configuration in which the metal plating layer PL includes the sixth electrode layer E6, the sixth electrode layer E6 is disposed on the second electrode layer E2. The sixth electrode layer E6 covers the second electrode layer E2. The sixth electrode layer E6 is in contact with the second electrode layer E2. The sixth electrode layer E6 is in direct contact with the second electrode layer E2. The third electrode layer E3 is disposed on the sixth electrode layer E6. The third electrode layer E3 is disposed on the outside of the second electrode layer E2. The third electrode layer E3 covers the sixth electrode layer E6. The third electrode layer E3 is in contact with the sixth electrode layer E6. That is, the third electrode layer E3 is in direct contact with the sixth electrode layer E6. The third electrode layer E3 is formed on the sixth electrode layer E6 by a plating method. The sixth electrode layer E6 is formed on the second electrode layer E2 by a plating method. The sixth electrode layer E6 is formed, for example, on the second electrode layer E2 by Ni plating. The sixth electrode layer E6 is a Ni plating layer. The sixth electrode layer E6 contains Ni. The sixth electrode layer E6 covers the second electrode layer E2.

[0057] Between the end of the sixth electrode layer E6 and the element body 3, there is a gap, similar to between the end of each of the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 and the element body 3. That is, there is a gap between the side surfaces 3a and 3c, and between the end of the sixth electrode layer E6 and the ridge between the side surfaces 3a and 3c. There is a gap between the end of the sixth electrode layer E6 and the side surfaces 3a and 3c, and between the end of the sixth electrode layer E6 and the ridge between the side surfaces 3a and 3c. The distance between the end of the sixth electrode layer E6 and the side surfaces 3a and 3c, i.e., the width of the above-mentioned gap, is, for example, greater than 0 and 3 μm or less. The width of the gap between the end of the sixth electrode layer E6 and the ridge between the side surfaces 3a and 3c is, for example, greater than 0 and 3 μm or less. The width of the gap between the end of the sixth electrode layer E6 and the element body 3 may be the same as or different from the width of the gap between each end of the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 and the element body 3. The width of the gap between the end of the sixth electrode layer E6 and the side surface 3a, the width of the gap between the end of the sixth electrode layer E6 and the side surface 3c, and the width of the gap between the end of the sixth electrode layer E6 and the ridge between the side surface 3a and the side surface 3c may be the same as or different from each other.

[0058] In the present embodiment and the modified example, 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, multilayer solid-state battery components, and multilayer composite components, or electronic components other than multilayer electronic components. [Explanation of symbols]

[0059] 3...element body, 5...external electrode, 13...Ag particles, 15...oxide, C1...multilayer capacitor, E2...second electrode layer, E3...third electrode layer, E4...fourth electrode layer, E5...fifth electrode layer, PL...metal plating layer.

Claims

1. The body and an external electrode disposed on the element body, the external electrode including a conductive resin layer containing a plurality of Ag particles and a metal plating layer disposed on the outside of the conductive resin layer with a gap between the conductive resin layer and the element body; an oxide of a metal component contained in the metal plating layer disposed in the gap between the metal plating layer and the base body and in contact with an end of the metal plating layer and the base body.

2. The metal plating layer includes a Cu plating layer, The electronic component according to claim 1 , wherein the oxide includes an oxide of Cu contained in the Cu plating layer.

3. 3. The electronic component according to claim 2, wherein the metal plating layer includes a metal plating layer other than the Cu plating layer, the metal plating layer being disposed outside the Cu plating layer with a gap between the metal plating layer and the base body.

4. The electronic component according to claim 3 , wherein the metal plating layer other than the Cu plating layer includes a Ni plating layer.

5. The electronic component according to claim 4 , wherein the metal plating layer other than the Cu plating layer includes a solder plating layer disposed outside the Ni plating layer.

6. The electronic component according to claim 5 , wherein the solder plating layer has a gap between it and the element body.

7. The electronic component according to any one of claims 1 to 5, wherein the oxide extends along an edge of the conductive resin layer.

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