Electronic components

Abstract

To provide an electronic component that suppresses the decrease in insulation resistance. [Solution] The multilayer capacitor C1 includes a base body 3 including a side surface 3e, an internal electrode 7 disposed within the base body 3, and an external electrode 5 disposed on the side surface 3e and connected to the internal electrode 7. The external electrode 5 includes a first electrode layer E1, a second electrode layer E2 located on the first electrode layer E1, and a third electrode layer E3 located on the second electrode layer E2. The second electrode layer E2 contains one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, and has a thickness of 5 μm or more. The third electrode layer E3 contains Ni.

Description

Technical Field

[0001] Aspects of the present invention relate to electronic components.

Background Art

[0002] A known electronic component includes an element body including a side surface, an inner conductor disposed inside the element body, and an outer conductor disposed on the side surface and connected to the inner conductor (see, for example, Patent Document 1). The outer conductor includes a base electrode layer, and a plating layer that is located on the base electrode layer and contains Ni.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] In a configuration where the outer conductor includes a Ni-containing plating layer, hydrogen generated in the process of forming the Ni-containing plating layer may remain in the Ni-containing plating layer. The hydrogen remaining in the Ni-containing plating layer may diffuse into the element body after diffusing through the base electrode layer. Hydrogen diffused into the element body may reduce the insulation resistance of the electronic component.

[0005] An object of aspects of the present invention is to provide an electronic component that suppresses a decrease in insulation resistance.

Means for Solving the Problem

[0006] An electronic component according to one aspect of the present invention includes a base body including a side surface, an internal conductor disposed within the base body, and an external conductor disposed on the side surface and connected to the internal conductor. The external conductor includes a base electrode layer, a metal plating layer located on the base electrode layer, and a plating layer located on the metal plating layer and containing Ni. The metal plating layer contains one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, and has a thickness of 5 μm or more.

[0007] In one embodiment described above, a metal plating layer containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, and having a thickness of 5 μm or more, is positioned between the base electrode layer and the Ni plating layer. Therefore, the metal plating layer suppresses the diffusion of hydrogen from the Ni plating layer to the base electrode layer. As a result, this embodiment suppresses the decrease in insulation resistance.

[0008] An electronic component according to another aspect of the present invention includes a body including a side surface, an internal conductor disposed within the body, and an external conductor disposed on the side surface and connected to the internal conductor. The external conductor includes a base electrode layer, a metal plating layer located on the base electrode layer, and a plating layer located on the metal plating layer and containing Ni. The metal plating layer contains a Sn-M alloy (where M is one metal selected from the group consisting of Cu, Ag, Bi, Zn, and Co) and has a thickness of 5 μm or more.

[0009] In one of the other embodiments described above, the metal plating layer located between the base electrode layer and the Ni plating layer contains a Sn-M alloy (where M is one metal selected from the group consisting of Cu, Ag, Bi, Zn, and Co) and has a thickness of 5 μm or more. Therefore, the metal plating layer suppresses the diffusion of hydrogen from the Ni plating layer to the base electrode layer. As a result, the other embodiment described above suppresses the decrease in insulation resistance. [Effects of the Invention]

[0010] Each aspect of the present invention provides an electronic component that suppresses the decrease in insulation resistance. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a perspective view of a multilayer capacitor according to one embodiment. [Figure 2] Figure 2 shows the cross-sectional configuration of the multilayer capacitor according to this embodiment. [Figure 3] Figure 3 shows a cross-sectional configuration of a multilayer capacitor according to a modified example of this embodiment. [Figure 4] Figure 4 is a chart showing the test results for each sample. [Figure 5] Figure 5 is a chart showing the test results for each sample. [Modes for carrying out the invention]

[0012] Embodiments of the present invention will be described in detail below with reference to the attached drawings. In this description, the same reference numerals will be used for elements that are the same or have the same function, and redundant explanations will be omitted.

[0013] The configuration of the multilayer capacitor C1 according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a perspective view of the multilayer capacitor according to this embodiment. Figure 2 is a diagram showing the cross-sectional configuration of the multilayer capacitor according to this embodiment. The electronic components include, for example, a multilayer capacitor C1.

[0014] As shown in Figure 1, the multilayer capacitor C1 includes a rectangular parallelepiped base 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 surface of the base 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, or a rectangular parallelepiped shape with rounded corners and edges.

[0015] Body 3 includes four sides 3a and a pair of opposing sides 3e. The four sides 3a and the pair of sides 3e are rectangular in shape. The four sides 3a include a first pair of opposing sides 3a and a second pair of opposing sides 3a. The direction in which the first pair of sides 3a face each other is direction D2. The direction in which the second pair of sides 3a face each other is direction D3. The direction in which the pair of sides 3e face each other is direction D1. Sides 3e include the sides of body 3. The multilayer capacitor C1 is soldered to an electronic device, for example, which includes a circuit board or other electronic components. In the multilayer capacitor C1, one of the four sides 3a faces the electronic device. One side 3a is positioned to form the mounting surface. One side 3a is the mounting surface.

[0016] Direction D2 is perpendicular to the first pair of sides 3a and perpendicular to direction D3. Direction D1 is parallel to the first pair of sides 3a and the second pair of sides 3a and perpendicular to directions D2 and D3. Direction D3 is perpendicular to the second pair of sides 3a, and direction D1 is perpendicular to the pair of sides 3e. The length of the element 3 in direction D1 is, for example, greater than the length of the element 3 in direction D2 and greater than the length of the element 3 in direction D3. Direction D1 is the longitudinal direction of the element 3. The length of the element 3 in direction D2 and the length of the element 3 in direction D3 may be equal to each other. The length of the element 3 in direction D2 and the length of the element 3 in direction D3 may be different to each other.

[0017] The length of base body 3 in direction D2 is the height of base body 3. The length of base body 3 in direction D3 is the width of base body 3. The length of base body 3 in direction D1 is the length of base body 3 in its longitudinal direction. For example, the height of base body 3 is 0.1 to 3.2 mm, the width of base body 3 is 0.1 to 6.3 mm, and the length of base body 3 is 0.2 to 7.5 mm. For example, the height of base body 3 is 0.33 mm, the width of base body 3 is 0.30 mm, and the length of base body 3 is 0.60 mm.

[0018] The first pair of side surfaces 3a extend in direction D3 so as to connect the second pair of side surfaces 3a. The first pair of side surfaces 3a also extend in direction D1. The second pair of side surfaces 3a extend in direction D2 so as to connect the first pair of side surfaces 3a. The second pair of side surfaces 3a also extend in direction D1. The pair of side surfaces 3e extend in direction D2 so as to connect the first pair of side surfaces 3a. The pair of side surfaces 3e extend in direction D3 so as to connect the second pair of side surfaces 3a.

[0019] The element body 3 includes, for example, a first ridge portion located between the side surface 3e and the side surface 3a, and a second ridge portion located between one of the first pair of side surfaces 3a and one of the second pair of side surfaces 3a. For example, the first ridge portion and the second ridge portion are rounded to be curved. For example, so-called R-chamfering is performed on the element body 3. The side surface 3e and the side surface 3a are indirectly adjacent to each other via the first ridge portion. One of the first pair of side surfaces 3a and one of the second pair of side surfaces 3a are indirectly adjacent to each other via the second ridge portion.

[0020] The element body 3 is configured by laminating a plurality of dielectric layers in the direction D2. The element body 3 includes the plurality of laminated dielectric layers. In the element body 3, the lamination direction of the plurality of dielectric layers coincides with the direction D2. Each dielectric layer is formed of, for example, a sintered body of a ceramic green sheet containing a dielectric material. The dielectric material includes a dielectric ceramic. The dielectric ceramic includes, for example, a BaTiO3-based, Ba(Ti,Zr)O3-based, or (Ba,Ca)TiO3-based material. In an actual element body 3, the dielectric layers are integrated to such an extent that the boundaries between the respective dielectric layers are not visible. In the element body 3, the lamination direction of the plurality of dielectric layers may coincide with the direction D3.

[0021] The multilayer capacitor C1 includes a plurality of internal electrodes 7, as shown in Figure 2. Each internal electrode 7 includes an internal conductor located within the element 3. Each internal electrode 7 is made of a conductive material commonly used as an internal conductor in multilayer electronic components. The conductive material includes, for example, a base metal. The conductive material includes, for example, Ni or Cu. The internal electrode 7 is constructed as a sintered body of a conductive paste containing the above conductive material. For example, the internal electrode 7 is made of Ni.

[0022] Multiple internal electrodes 7 are arranged in different positions (layers) in direction D2. Multiple internal electrodes 7 are arranged in the base body 3 so as to face each other with a gap in direction D2. Adjacent internal electrodes 7 in direction D2 have different polarities. One end of an internal electrode 7 is exposed from the corresponding side 3e of a pair of side surfaces 3e. An internal electrode 7 includes the end exposed from the corresponding side surface 3e. Multiple internal electrodes 7 include internal electrodes 7 exposed from one side surface 3e of a pair of side surfaces 3e and internal electrodes 7 exposed from the other side surface 3e of a pair of side surfaces 3e. The internal electrodes 7 exposed from one side surface 3e and the internal electrodes 7 exposed from the other side surface 3e are arranged alternately in direction D2. Multiple internal electrodes 7 are arranged in the base body 3 so as to be aligned in direction D2. The internal electrodes 7 are located in a plane substantially parallel to the first pair of side surfaces 3a. The direction in which the internal electrodes 7 face each other is perpendicular to the direction parallel to the first pair of side surfaces 3a.

[0023] In a configuration where the stacking direction of multiple dielectric layers includes direction D3, the multiple internal electrodes 7 are arranged at different positions (layers) in direction D3. In this configuration, the internal electrodes 7 exposed from one side surface 3e and the internal electrodes 7 exposed from the other side surface 3e are arranged alternately in direction D3. The internal electrodes 7 are located in a plane substantially parallel to the second pair of side surfaces 3a. The internal electrodes 7 face each other in direction D3.

[0024] The external electrodes 5 are located at both ends of the body 3 in direction D1, as shown in Figures 1 and 2. Each external electrode 5 is located on a corresponding side 3e of the body 3. Each external electrode 5 includes an external conductor located on a corresponding side 3e. For example, each external electrode 5 is located on four sides 3a and one side 3e. The external electrode 5 includes a plurality of electrode portions 5a, 5e. Electrode portion 5a is located on side 3a. Electrode portion 5a may be located on the ridge (first ridge) between side 3a and side 3e. Electrode portion 5e is located on side 3e. The external electrode 5 also includes electrode portions located on the ridge (second ridge) between adjacent side 3a.

[0025] The external electrode 5 is formed on five surfaces: four sides 3a and one side 3e. Adjacent electrode portions 5a and 5e are physically connected and electrically connected. Electrode portion 5e completely covers one end of a corresponding internal electrode 7 among a plurality of internal electrodes 7. 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. The external electrode 5 includes a first electrode layer E1, a second electrode layer E2, a third electrode layer E3, and a fourth electrode layer E4, as shown in Figure 2. For example, the fourth electrode layer E4 includes the outermost layer of the external electrode 5. Each electrode portion 5a, 5e includes the first electrode layer E1, the second electrode layer E2, the third electrode layer E3, and the fourth electrode layer E4.

[0026] The first electrode layer E1 of electrode portion 5a is positioned on the side surface 3a. The first electrode layer E1 of electrode portion 5a covers a portion of the side surface 3a. The first electrode layer E1 of electrode portion 5a is in contact with the aforementioned portion of the side surface 3a. Except for the portion covered by the first electrode layer E1, the side surface 3a is exposed from the first electrode layer E1. The portion covered by the first electrode layer E1 of electrode portion 5a is located closer to the side surface 3e. The second electrode layer E2 of electrode portion 5a is positioned on the first electrode layer E1. In electrode portion 5a, the second electrode layer E2 completely covers the first electrode layer E1. In electrode portion 5a, the second electrode layer E2 indirectly covers a portion of the side surface 3a such that the first electrode layer E1 is positioned between the second electrode layer E2 and the base body 3. The second electrode layer E2 of electrode portion 5a is located on the side surface 3a. In electrode portion 5a, the second electrode layer E2 is located on the first electrode layer E1. For example, in electrode portion 5a, the second electrode layer E2 is in contact with the first electrode layer E1.

[0027] The third electrode layer E3 of electrode portion 5a is located on the second electrode layer E2. In electrode portion 5a, the third electrode layer E3 completely covers the second electrode layer E2. In electrode portion 5a, the third electrode layer E3 indirectly covers the first electrode layer E1 such that the second electrode layer E2 is located between the third electrode layer E3 and the first electrode layer E1. In electrode portion 5a, the third electrode layer E3 does not contact the first electrode layer E1. The third electrode layer E3 of electrode portion 5a is located on the side surface 3a. In electrode portion 5a, the third electrode layer E3 is located on the second electrode layer E2. For example, in electrode portion 5a, the third electrode layer E3 is in contact with the second electrode layer E2. The fourth electrode layer E4 of electrode portion 5a is located on the third electrode layer E3. In electrode portion 5a, the fourth electrode layer E4 completely covers the third electrode layer E3. In electrode portion 5a, the fourth electrode layer E4 indirectly covers the second electrode layer E2 such that the third electrode layer E3 is located between the fourth electrode layer E4 and the second electrode layer E2. In electrode portion 5a, the fourth electrode layer E4 does not contact the second electrode layer E2. The fourth electrode layer E4 of electrode portion 5a is located on the side surface 3a. In electrode portion 5a, the fourth electrode layer E4 is located on the third electrode layer E3. For example, in electrode portion 5a, the fourth electrode layer E4 is in contact with the third electrode layer E3. In electrode portion 5a, the second electrode layer E2, the third electrode layer E3, and the fourth electrode layer E4 are located outside the first electrode layer E1.

[0028] The first electrode layer E1 of electrode portion 5e is positioned on the side surface 3e. The first electrode layer E1 of electrode portion 5e completely covers the side surface 3e. The first electrode layer E1 of electrode portion 5e is in contact with the side surface 3e. The first electrode layer E1 of electrode portion 5e is connected to one end of the corresponding internal electrode 7. The second electrode layer E2 of electrode portion 5e is located on the first electrode layer E1. In electrode portion 5e, the second electrode layer E2 completely covers the first electrode layer E1. In electrode portion 5e, the second electrode layer E2 indirectly covers the side surface 3e such that the first electrode layer E1 is located between the second electrode layer E2 and the side surface 3e. The second electrode layer E2 of electrode portion 5e is located on the side surface 3e. In electrode portion 5e, the second electrode layer E2 is located on the first electrode layer E1. For example, in electrode portion 5e, the second electrode layer E2 is in contact with the first electrode layer E1.

[0029] The third electrode layer E3 of electrode portion 5e is located on the second electrode layer E2. In electrode portion 5e, the third electrode layer E3 completely covers the second electrode layer E2. In electrode portion 5e, the third electrode layer E3 indirectly covers the first electrode layer E1 such that the second electrode layer E2 is located between the third electrode layer E3 and the first electrode layer E1. In electrode portion 5e, the third electrode layer E3 does not contact the first electrode layer E1. The third electrode layer E3 of electrode portion 5e is located on the side surface 3e. In electrode portion 5e, the third electrode layer E3 is located on the second electrode layer E2. For example, in electrode portion 5e, the third electrode layer E3 is in contact with the second electrode layer E2. The fourth electrode layer E4 of electrode portion 5e is located on the third electrode layer E3. In electrode portion 5e, the fourth electrode layer E4 completely covers the third electrode layer E3. In electrode portion 5e, the fourth electrode layer E4 indirectly covers the second electrode layer E2 such that the third electrode layer E3 is located between the fourth electrode layer E4 and the second electrode layer E2. In electrode portion 5e, the fourth electrode layer E4 does not contact the second electrode layer E2. The fourth electrode layer E4 of electrode portion 5e is located on the side surface 3e. In electrode portion 5e, the fourth electrode layer E4 is located on the third electrode layer E3. For example, in electrode portion 5e, the fourth electrode layer E4 is in contact with the third electrode layer E3. In electrode portion 5e, the second electrode layer E2, the third electrode layer E3, and the fourth electrode layer E4 are located outside the first electrode layer E1.

[0030] The first electrode layer E1 is formed, for example, by baking a conductive paste applied to the surface of the base body 3. The conductive paste is applied to a portion of the surface 3a and one surface 3e. The first electrode layer E1 is formed to cover a portion of each of the four surface 3a and one surface 3e. The first electrode layer E1 is formed by sintering the metal component (metal powder) contained in the conductive paste. The first electrode layer E1 includes, for example, a sintered metal layer. The first electrode layer E1 includes a sintered metal layer formed on the base body 3. The first electrode layer E1 includes, for example, a sintered metal layer made of Cu. The first electrode layer E1 may also include a sintered metal layer made of Ni. The first electrode layer E1 may also include a base metal. The conductive paste may include, for example, powder made of Cu or Ni, a glass component, an organic binder, and an organic solvent. The first electrode layer E1 included in the electrode portions 5a and 5e is, for example, formed integrally with each other. The first electrode layer E1 has a thickness of, for example, 5 to 20 μm.

[0031] The second electrode layer E2 is formed on the first electrode layer E1 via a plating process. The first electrode layer E1 includes a base electrode layer for forming the plating layer. The second electrode layer E2 includes, for example, a metal plating layer. The plating process includes an electroplating process. The second electrode layer E2 includes an electroplating layer. The second electrode layer E2 includes any one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co. The second electrode layer E2 may contain unavoidable trace amounts of impurities. The metal contained in the second electrode layer E2 may be substantially only one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co. For example, the second electrode layer E2 contains Sn. For example, the second electrode layer E2 contains a Sn plating layer. The second electrode layer E2 has a thickness of 5 μm or more. The second electrode layer E2 may have a thickness of 10 μm or less. The second electrode layer E2 may contain 0.1 to 0.5 mol% of sulfur (S). That is, the amount of sulfur (S) in the second electrode layer E2 may be 0.1 to 0.5 mol per 100 mol of metal components.

[0032] The third electrode layer E3 is formed on the second electrode layer E2 via a Ni plating process. The third electrode layer E3 contains Ni. The third electrode layer E3 includes a Ni plating layer. The Ni plating process includes an electrolytic Ni plating process. The third electrode layer E3 includes an electrolytic Ni plating layer. The third electrode layer E3 tends to have better solder corrosion resistance than the metal contained in the first electrode layer E1. The third electrode layer E3 has a thickness of, for example, 2 to 8 μm. The fourth electrode layer E4 is formed on the third electrode layer E3 via a plating process. The fourth electrode layer E4 includes, for example, a solder plating layer. The plating process includes an electrolytic solder plating process. The fourth electrode layer E4 includes an electrolytic solder plating layer. The solder plating layer includes, for example, a Sn plating layer. In configurations where the solder plating layer includes a Sn plating layer, the fourth electrode layer E4 includes Sn. The fourth electrode layer E4 may include a Sn-Ag alloy plating layer, a Sn-Bi alloy plating layer, or a Sn-Cu alloy plating layer instead of a Sn plating layer. The solder plating layer tends to have excellent solder mountability. The fourth electrode layer E4 has, for example, a thickness of 4 to 8 μm.

[0033] Next, with reference to Figure 3, the configuration of a modified multilayer capacitor C2 according to this embodiment will be described. Figure 3 is a diagram showing the cross-sectional configuration of the multilayer capacitor according to this modified embodiment. The multilayer capacitor C2 is generally similar to or the same as the multilayer capacitor C1, but the multilayer capacitor C2 differs from the multilayer capacitor C1 in terms of the configuration of the external electrodes 5. The differences between the multilayer capacitor C1 and the multilayer capacitor C2 will be mainly described below.

[0034] The multilayer capacitor C2, like the multilayer capacitor C1 described above, includes a base body 3, a plurality of external electrodes 5, and a plurality of internal electrodes 7. The external electrode 5 includes a first electrode layer E1, a second electrode layer E21, a third electrode layer E3, and a fourth electrode layer E4, as shown in Figure 3. Each electrode portion 5a, 5e includes the first electrode layer E1, the second electrode layer E21, the third electrode layer E3, and the fourth electrode layer E4.

[0035] The second electrode layer E21 is formed on the first electrode layer E1 via a plating process. For example, the second electrode layer E21 includes a metal plating layer, similar to the second electrode layer E2. The plating process includes an electroplating process. The second electrode layer E21 includes an electroplating layer. The second electrode layer E21 includes a Sn-M alloy. M is one metal selected from the group consisting of Cu, Ag, Bi, Zn, and Co. The second electrode layer E21 may contain unavoidable trace amounts of impurities. The metal contained in the second electrode layer E21 may be substantially only a Sn-M alloy. For example, the second electrode layer E21 includes a Sn-Cu alloy. For example, the second electrode layer E21 includes a Sn-Cu alloy plating layer. The second electrode layer E21 has a thickness of 5 μm or more. The second electrode layer E21 may have a thickness of 10 μm or less. The second electrode layer E21 may contain 0.1 to 0.5 mol% of S (sulfur). In other words, the amount of sulfur (S) may be 0.1 to 0.5 mol per 100 mol of metal components contained in the second electrode layer E21. The second electrode layer E21 may also contain 0.1 to 0.5 mol% phosphorus (P). In other words, the amount of phosphorus (P) may be 0.1 to 0.5 mol per 100 mol of metal components contained in the second electrode layer E21. The third electrode layer E3 is formed on the second electrode layer E21 via a Ni plating process. In this modified example, the third electrode layer E3 includes a Ni plating layer located on the second electrode layer E21. The fourth electrode layer E4 includes a Sn plating layer.

[0036] Next, the inventors conducted the following tests to confirm that the multilayer capacitors C1 and C2 described above suppress the decrease in insulation resistance. In these tests, the inventors prepared samples S1 to S30 with different configurations of the second electrode layers E2 and E21, and confirmed the change in insulation resistance and thermal stress resistance in each sample S1 to S30. The test results are shown in Figures 4 and 5. Figures 4 and 5 are charts showing the test results for each sample.

[0037] Each sample S1 to S30 is a lot containing multiple samples. Each sample S1 to S30 is a multilayer capacitor with the same configuration except that the type of metal plating layer in the second electrode layers E2 and E21, the thickness of the second electrode layers E2 and E21, the sulfur (S) content in the second electrode layers E2 and E21, and the phosphorus (P) content in the second electrode layer E21 differ. In samples S1 to S30, the height of the element 3 is 0.33 mm, the width of the element 3 is 0.30 mm, and the length of the element 3 is 0.60 mm. The capacitance of each sample is 1.0 μF, and the insulation resistance is 1.0 × 10⁻⁶. 9 It is Omega.

[0038] In sample S1, the second electrode layer E2 contains a Sn plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S2, the second electrode layer E2 contains an In plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S3, the second electrode layer E2 contains a Zn plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S4, the second electrode layer E2 contains an Au plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S5, the second electrode layer E2 contains an Ag plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S6, the second electrode layer E2 contains a Cu plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S7, the second electrode layer E2 contains a Cr plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S8, the second electrode layer E2 contains a Mn plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S9, the second electrode layer E2 contains an Fe plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S10, the second electrode layer E2 contains a Co plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S11, the second electrode layer E2 contains a Sn plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.1 mol%. In sample S12, the second electrode layer E2 contains a Sn plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.3 mol%. In sample S13, the second electrode layer E2 contains a Sn plating layer and has a thickness of 7 μm. The sulfur (S) content is 0.5 mol%. In sample S14, the second electrode layer E2 contains a Sn plating layer and has a thickness of 10 μm. The sulfur (S) content is 0.5 mol%. In sample S15, the second electrode layer E2 contains a Sn plating layer and has a thickness of 12 μm. The sulfur (S) content is 0.5 mol%. In sample S16, the external electrode 5 does not include the second electrode layer E2. That is, the third electrode layer E3 is in contact with the first electrode layer E1. In sample S17, the second electrode layer E2 contains a Ni plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S18, the second electrode layer E2 contains a Sn plating layer and has a thickness of 3 μm. The sulfur (S) content is 0.5 mol%.

[0039] In sample S19, the second electrode layer E2 contains a Sn-Cu alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S20, the second electrode layer E2 contains a Sn-Ag alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S21, the second electrode layer E2 contains a Sn-Bi alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S22, the second electrode layer E2 contains a Sn-Zn alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S23, the second electrode layer E2 contains a Sn-Co alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S24, the second electrode layer E2 contains a Sn-Cu alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.1 mol%, and the phosphorus (P) content is 0.1 mol%. In sample S25, the second electrode layer E2 contains a Sn-Cu alloy plating layer with a thickness of 5 μm. The sulfur (S) content is 0.3 mol%, and the phosphorus (P) content is 0.3 mol%. In sample S26, the second electrode layer E2 contains a Sn-Cu alloy plating layer with a thickness of 7 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S27, the second electrode layer E2 contains a Sn-Cu alloy plating layer with a thickness of 10 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S28, the second electrode layer E2 contains a Sn-Ni alloy plating layer and has a thickness of 5 μm. The sulfur (S) content is 0.5 mol%. In sample S29, the second electrode layer E2 contains a Sn-Cu alloy plating layer with a thickness of 3 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%. In sample S30, the second electrode layer E2 contains a Sn-Cu alloy plating layer and has a thickness of 12 μm. The sulfur (S) content is 0.5 mol%, and the phosphorus (P) content is 0.5 mol%.

[0040] Changes in insulation resistance are confirmed by the results of a moisture load test, which includes the following procedure. For each sample S1 to S30, 100 samples are selected and soldered onto a substrate (glass epoxy substrate). The substrate with the mounted samples is placed in a constant temperature and humidity chamber, and a predetermined voltage is applied to the mounted samples for a predetermined time under conditions of 125°C and 95% RH relative humidity. The predetermined voltage is set to 6.3V, and the predetermined time is set to 168 hours. After the predetermined time has elapsed, the insulation resistance of the samples mounted on the substrate is measured. Samples with an measured insulation resistance of less than 1MΩ are judged as "defective". For each sample S1 to S30, the number of samples judged as "defective" is counted. If the number of samples judged as "defective" out of 100 samples is 15 or less, it is determined that the change in insulation resistance is suppressed.

[0041] Thermal stress tolerance is confirmed by the results of a thermal stress test that includes the following procedure. For each sample S1 to S30, 100 samples are selected and placed in a heating furnace for a predetermined time. The heating furnace is kept under a nitrogen atmosphere, and the heat treatment temperature is set to 260°C. The predetermined time is set to 10 minutes. After heat treatment, a visual inspection is performed, and samples in which cracks are confirmed are judged as "defective". The number of samples judged as "defective" for each sample S1 to S30 is counted. If the number of samples judged as "defective" out of 100 is 10 or less, the thermal stress resistance is judged to be good.

[0042] As a result of the tests described above, as shown in Figure 4, it was confirmed that the change in insulation resistance was suppressed in samples S1 to S15 compared to samples S16 to S17. In samples S1, S11 to S15, it was confirmed that the change in insulation resistance was suppressed even further. In samples S3, S5, and S6, although inferior to sample S1, it was confirmed that the change in insulation resistance was suppressed compared to samples S2, S4, S7 to S10. Samples S1 to S14 were found to have better thermal stress resistance compared to sample S15. As shown in Figure 5, it was confirmed that the change in insulation resistance was suppressed in samples S19 to S28 compared to samples S29 to S30. In samples S19 and S24 to S28, it was confirmed that the change in insulation resistance was suppressed even further. In samples S20 and S22, although inferior to sample S19, it was confirmed that the change in insulation resistance was suppressed compared to samples S21 and S23. Samples S19 to S27 were found to have better thermal stress resistance compared to sample S28.

[0043] In the multilayer capacitor C1, the second electrode layer E2 is located between the first electrode layer E1 and the third electrode layer E3. The second electrode layer E2 is a metal plating layer containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, and has a thickness of 5 μm or more. Therefore, the second electrode layer E2 suppresses the diffusion of hydrogen from the third electrode layer E3 to the first electrode layer E1. As a result, the multilayer capacitor C1 suppresses a decrease in insulation resistance.

[0044] In the multilayer capacitor C1, the second electrode layer E2 may contain 0.1 to 0.5 mol% of sulfur (S). Even when the second electrode layer E2 contains 0.1 to 0.5 mol% of sulfur (S), the decrease in insulation resistance is suppressed.

[0045] The second electrode layer E2 may be a plating layer containing Sn. The configuration in which the second electrode layer E2 is a plating layer containing Sn further suppresses the decrease in insulation resistance.

[0046] In the multilayer capacitor C2, the second electrode layer E21 is located between the first electrode layer E1 and the third electrode layer E3. The second electrode layer E21 is a metal plating layer containing a Sn-M alloy (where M is one metal selected from the group consisting of Cu, Ag, Bi, Zn, and Co) and has a thickness of 5 μm or more. Therefore, the second electrode layer E21 suppresses the diffusion of hydrogen from the third electrode layer E3 to the first electrode layer E1. As a result, the multilayer capacitor C2 suppresses a decrease in insulation resistance.

[0047] The second electrode layer E21 may be a plating layer containing a Sn-Cu alloy. The configuration in which the second electrode layer E21 is a plating layer containing a Sn-Cu alloy further suppresses the decrease in insulation resistance.

[0048] In the multilayer capacitor C2, the second electrode layer E21 may contain 0.1 to 0.5 mol% of sulfur (S). The second electrode layer E21 may also contain 0.1 to 0.5 mol% of phosphorus (P). Even when the second electrode layer E21 contains 0.1 to 0.5 mol% of sulfur (S), the decrease in insulation resistance is suppressed. Even when the second electrode layer E21 contains 0.1 to 0.5 mol% of phosphorus (P), the decrease in insulation resistance is suppressed.

[0049] The second electrode layers E2 and E21 may have a thickness of 10 μm or less. The configuration in which the second electrode layers E2 and E21 have a thickness of 10 μm or less reduces the stress acting from the second electrode layers E2 and E21 to the base body 3, even in environments where thermal stress is applied. Therefore, this configuration suppresses the occurrence of cracks in the base body 3. This configuration suppresses the decrease in thermal stress resistance. Based on the test results described above, it is presumed that thermal stress resistance is affected by the thickness of the second electrode layers E2 and E21. Therefore, it is presumed that even if the second electrode layers E2 and E21 are plating layers containing one metal other than Sn, selected from the group consisting of In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, the decrease in thermal stress resistance will be suppressed.

[0050] The multilayer capacitors C1 and C2 may include a fourth electrode layer E4. The multilayer capacitors C1 and C2, which include the fourth electrode layer E4, offer excellent solderability.

[0051] The second electrode layers E2 and E21 may include an electroplating layer. Electroplated layers tend to have high adhesion to the substrate and high abrasion resistance. In contrast, electroless plating layers tend to have low adhesion to the substrate and low abrasion resistance. Therefore, second electrode layers E2 and E21 that include an electroplated layer tend to have high adhesion and high abrasion resistance. In other words, the bonding properties and durability of the second electrode layers E2 and E21 are improved. As a result, the second electrode layers E2 and E21 further suppress the diffusion of hydrogen from the third electrode layer E3 to the first electrode layer E1. The configuration in which the second electrode layers E2 and E21 include an electroplated layer further suppresses the decrease in insulation resistance.

[0052] In this specification, when an element is described as being placed on another element, that element may be placed directly on the other element or indirectly on it. If an element is placed indirectly on another element, an intervening element exists between the two elements. If an element is placed directly on another element, no intervening element exists between the two elements. In this specification, when an element is described as being located on another element, that element may be located directly on the other element or indirectly on the other element. If an element is located indirectly on another element, an intervening element exists between the two elements. If an element is located directly on another element, no intervening element exists between the two elements. In this specification, when an element is described as covering another element, that element may directly cover the other element or indirectly cover it. If an element indirectly covers another element, an intervening element exists between the two elements. If an element directly covers another element, no intervening element exists between the two elements.

[0053] While embodiments of the present invention have been described above, the present invention is not necessarily limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention.

[0054] In this embodiment and its modified examples, a multilayer capacitor was used as an example of an electronic component. However, the 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, or multilayer composite components, or electronic components other than multilayer electronic components.

[0055] As can be seen from the embodiments and modifications described above, this specification includes disclosures of the following aspects. (Note 1) The base body including the sides, The internal conductor arranged within the aforementioned body, The system comprises an outer conductor arranged on the side and connected to the inner conductor, The aforementioned external conductor is The base electrode layer, A metal plating layer located on the aforementioned under electrode layer, The aforementioned metal plating layer is located on the aforementioned metal plating layer and includes a plating layer containing Ni, The aforementioned metal plating layer contains one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, and has a thickness of 5 μm or more, in an electronic component. (Note 2) The aforementioned metal plating layer is an electronic component as described in Appendix 1, containing Sn. (Note 3) The base body including the sides, The internal conductor arranged within the aforementioned body, The system comprises an outer conductor arranged on the side and connected to the inner conductor, The aforementioned external conductor is The base electrode layer, A metal plating layer located on the aforementioned under electrode layer, The aforementioned metal plating layer is located on the aforementioned metal plating layer and includes a plating layer containing Ni, The aforementioned metal plating layer comprises a Sn-M alloy (where M is one metal selected from the group consisting of Cu, Ag, Bi, Zn, and Co) and has a thickness of 5 μm or more, in an electronic component. (Note 4) The aforementioned metal plating layer is an electronic component as described in Appendix 3, comprising a Sn-Cu alloy. (Note 5) The aforementioned metal plating layer contains 0.1 to 0.5 mol% of P (phosphorus), as described in Appendix 3 or 4 of the electronic component. (Note 6) The aforementioned metal plating layer contains 0.1 to 0.5 mol% of S (sulfur), as described in any one of the appendices 1 to 5 of the electronic component. (Note 7) The aforementioned metal plating layer has a thickness of 10 μm or less and is an electronic component as described in any one of Appendix 1 to 6. (Note 8) The electronic component according to any one of the appendices 1 to 7, wherein the outer conductor further comprises a solder plating layer located on the plating layer containing Ni. [Explanation of symbols]

[0056] 3…body, 3e…side, 5…external electrode, 7…internal electrode, C1, C2…comdensus, E1…first electrode layer, E2, E21…second electrode layer, E3…third electrode layer, E4…fourth electrode layer.

Claims

1. The base body including the sides, The internal conductor arranged within the aforementioned body, The system comprises an outer conductor arranged on the side and connected to the inner conductor, The aforementioned external conductor is The base electrode layer, A metal plating layer located on the aforementioned under electrode layer, The metal plating layer is located on the aforementioned metal plating layer and includes a plating layer containing Ni, The aforementioned metal plating layer contains one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cu, Cr, Mn, Fe, and Co, and has a thickness of 5 μm or more, in an electronic component.

2. The electronic component according to claim 1, wherein the metal plating layer contains Sn.

3. The base body including the sides, The internal conductor arranged within the aforementioned body, The system comprises an outer conductor arranged on the side and connected to the inner conductor, The aforementioned external conductor is The base electrode layer, A metal plating layer located on the aforementioned under electrode layer, The metal plating layer is located on the aforementioned metal plating layer and includes a plating layer containing Ni, The aforementioned metal plating layer comprises a Sn-M alloy (where M is one metal selected from the group consisting of Cu, Ag, Bi, Zn, and Co) and has a thickness of 5 μm or more, in an electronic component.

4. The electronic component according to claim 3, wherein the metal plating layer comprises a Sn-Cu alloy.

5. The electronic component according to claim 3, wherein the metal plating layer contains 0.1 to 0.5 mol% of P (phosphorus).

6. The electronic component according to any one of claims 1 to 5, wherein the metal plating layer contains 0.1 to 0.5 mol% of S (sulfur).

7. The electronic component according to any one of claims 1 to 5, wherein the metal plating layer has a thickness of 10 μm or less.

8. The electronic component according to any one of claims 1 to 5, wherein the outer conductor further comprises a solder plating layer located on the plating layer containing Ni.

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