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 containing Cu, a third electrode layer E3 located on the second electrode layer E2 and containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co, and a fourth electrode layer E4 located on the third electrode layer E3 and containing Ni.

Description

Technical Field

[0001] One aspect of the present invention relates to an electronic component.

Background Art

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

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 external 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 one aspect 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 sides, an internal conductor disposed within the base body, and an external conductor disposed on the sides and connected to the internal conductor. The external conductor includes a base electrode layer, a first plating layer located on the base electrode layer and containing Cu, a second plating layer located on the first plating layer and containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co, and a third plating layer located on the second plating layer and containing Ni.

[0007] In one embodiment described above, a first plating layer containing Cu and a second plating layer containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co are positioned between the base electrode layer and the third plating layer. Therefore, the first and second plating layers suppress the diffusion of hydrogen from the third plating layer to the base electrode layer. As a result, this embodiment suppresses the decrease in insulation resistance. [Effects of the Invention]

[0008] One aspect of the present invention provides an electronic component that suppresses the decrease in insulation resistance. [Brief explanation of the drawing]

[0009] [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 is a chart showing the test results for each sample. [Figure 4] Figure 4 is a chart showing the test results for each sample. [Modes for carrying out the invention]

[0010] 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 the same element or element having the same function, and redundant explanations will be omitted.

[0011] 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.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] The first pair of sides 3a extend in direction D3 to connect with the second pair of sides 3a. The first pair of sides 3a also extend in direction D1. The second pair of sides 3a extend in direction D2 to connect with the first pair of sides 3a. The second pair of sides 3a also extend in direction D1. The pair of sides 3e extend in direction D2 to connect with the first pair of sides 3a. The pair of sides 3e extend in direction D3 to connect with the second pair of sides 3a.

[0017] The base 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, the base body 3 is subjected to so-called R-chamfering. 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.

[0018] The base body 3 is configured by laminating a plurality of dielectric layers in the direction D2. The base body 3 includes the plurality of laminated dielectric layers. In the base body 3, the lamination direction of the plurality of dielectric layers coincides with the direction D2. Each dielectric layer is composed of, for example, a sintered body of a ceramic green sheet containing a dielectric material. The dielectric material includes dielectric ceramic. The dielectric ceramic includes, for example, BaTiO3-based, Ba(Ti,Zr)O3-based, or (Ba,Ca)TiO3-based materials. In an actual base body 3, the dielectric layers are integrated to such an extent that the boundaries between the respective dielectric layers cannot be visually recognized. In the base body 3, the lamination direction of the plurality of dielectric layers may coincide with the direction D3.

[0019] As shown in FIG. 2, the multilayer capacitor C1 includes a plurality of internal electrodes 7. Each of the internal electrodes 7 includes an internal conductor disposed inside the base body 3. Each internal electrode 7 is made of a conductive material generally used as an internal conductor for multilayer electronic components. The conductive material includes, for example, a base metal. The conductive material includes, for example, Ni or Cu. The internal electrode 7 is configured as a sintered body of a conductive paste containing the above conductive material. For example, the internal electrode 7 is made of Ni.

[0020] The plurality of internal electrodes 7 are arranged at different positions (layers) in the direction D2. The plurality of internal electrodes 7 are arranged so as to face each other with an interval in the direction D2 within the element body 3. Adjacent internal electrodes 7 in the direction D2 have different polarities from each other. One end of each internal electrode 7 is exposed from the corresponding side surface 3e of the pair of side surfaces 3e. The internal electrode 7 includes the one end exposed from the corresponding side surface 3e. The plurality of internal electrodes 7 include an internal electrode 7 exposed from one side surface 3e of the pair of side surfaces 3e, and an internal electrode 7 exposed from the other side surface 3e of the 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 alternately arranged in the direction D2. The plurality of internal electrodes 7 are arranged within the element body 3 so as to line up in the direction D2. The internal electrode 7 is 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 orthogonal to a direction parallel to the first pair of side surfaces 3a.

[0021] In a configuration in which the stacking direction of the plurality of dielectric layers includes the direction D3, the plurality of internal electrodes 7 are arranged at different positions (layers) in the 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 alternately arranged in the direction D3. The internal electrode 7 is located in a plane substantially parallel to the second pair of side surfaces 3a. The internal electrodes 7 face each other in the direction D3.

[0022] As shown in FIG. 1 and FIG. 2, the external electrodes 5 are arranged at both ends of the element body 3 in the direction D1. Each external electrode 5 is arranged on the corresponding side surface 3e of the element body 3. Each external electrode 5 includes an external conductor arranged on the corresponding side surface 3e. For example, each external electrode 5 is arranged on the four side surfaces 3a and one side surface 3e. The external electrode 5 includes a plurality of electrode portions 5a, 5e. The electrode portion 5a is located on the side surface 3a. The electrode portion 5a may be located on a ridge (first ridge) between the side surface 3a and the side surface 3e. The electrode portion 5e is located on the side surface 3e. The external electrode 5 also includes an electrode portion located on a ridge (second ridge) between adjacent side surfaces 3a.

[0023] 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, a fourth electrode layer E4, and a fifth electrode layer E5, as shown in Figure 2. For example, the fifth electrode layer E5 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, the fourth electrode layer E4, and the fifth electrode layer E5.

[0024] 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. 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.

[0025] 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. The fifth electrode layer E5 of electrode portion 5a is located on the fourth electrode layer E4. In electrode portion 5a, the fifth electrode layer E5 completely covers the fourth electrode layer E4. In electrode portion 5a, the fifth electrode layer E5 indirectly covers the third electrode layer E3 such that the fourth electrode layer E4 is located between the fifth electrode layer E5 and the third electrode layer E3. In electrode portion 5a, the fifth electrode layer E5 does not come into contact with the third electrode layer E3. The fifth electrode layer E5 of electrode portion 5a is located on the side surface 3a. In electrode portion 5a, the fifth electrode layer E5 is located on the fourth electrode layer E4. For example, in electrode portion 5a, the fifth electrode layer E5 comes into contact with the fourth electrode layer E4. In electrode portion 5a, the second electrode layer E2, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are located outside the first electrode layer E1.

[0026] 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. 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.

[0027] 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. The fifth electrode layer E5 of electrode portion 5e is located on the fourth electrode layer E4. In electrode portion 5e, the fifth electrode layer E5 completely covers the fourth electrode layer E4. In electrode portion 5e, the fifth electrode layer E5 indirectly covers the third electrode layer E3 such that the fourth electrode layer E4 is located between the fifth electrode layer E5 and the third electrode layer E3. In electrode portion 5e, the fifth electrode layer E5 does not contact the third electrode layer E3. The fifth electrode layer E5 of electrode portion 5e is located on the side surface 3e. In electrode portion 5e, the fifth electrode layer E5 is located on the fourth electrode layer E4. For example, in electrode portion 5e, the fifth electrode layer E5 is in contact with the fourth electrode layer E4. In electrode portion 5e, the second electrode layer E2, the third electrode layer E3, the fourth electrode layer E4, and the fifth electrode layer E5 are located outside the first electrode layer E1.

[0028] 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.

[0029] The second electrode layer E2 is formed on the first electrode layer E1 via a Cu plating process. The first electrode layer E1 includes a base electrode layer for forming the plating layer. The second electrode layer E2 contains Cu. The second electrode layer E2 may contain unavoidable trace amounts of impurities. The second electrode layer E2 includes a Cu plating layer. The Cu plating process includes an electrolytic Cu plating process. The second electrode layer E2 includes an electrolytic Cu plating layer. The second electrode layer E2 may have a thickness of 0.5 μm or more. The second electrode layer E2 may have a thickness of 4.5 μm or less. The second electrode layer E2 may contain 0.1 to 0.5 mol% of S (sulfur). That is, the amount of S (sulfur) in the second electrode layer E2 may be 0.1 to 0.5 mol per 100 mol of metal components.

[0030] The third electrode layer E3 is formed on the second electrode layer E2 via a plating process. The third electrode layer E3 includes, for example, a metal plating layer. The plating process includes an electroplating process. The third electrode layer E3 includes an electroplating layer. The third electrode layer E3 includes one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co. The third electrode layer E3 may contain unavoidable trace amounts of impurities. The metal contained in the third electrode layer E3 may be substantially only one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co. For example, the third electrode layer E3 contains Sn. For example, the third electrode layer E3 includes a Sn plating layer. The third electrode layer E3 may have a thickness of 0.5 μm or more. The third electrode layer E3 may have a thickness of 4.5 μm or less. The third electrode layer E3 may contain 0.1 to 0.5 mol% of sulfur (S). That is, the amount of sulfur (S) in the third electrode layer E3 may be 0.1 to 0.5 mol per 100 mol of metal components.

[0031] The fourth electrode layer E4 is formed on the third electrode layer E3 via a Ni plating process. The fourth electrode layer E4 contains Ni. The fourth electrode layer E4 includes a Ni plating layer. The Ni plating process includes an electrolytic Ni plating process. The fourth electrode layer E4 includes an electrolytic Ni plating layer. The fourth electrode layer E4 tends to have better solder corrosion resistance than the metals contained in the first electrode layer E1 and the second electrode layer E2. The fourth electrode layer E4 has a thickness of, for example, 2 to 8 μm. For example, if the second electrode layer E2 includes the first plating layer, the third electrode layer E3 includes the second plating layer, and the fourth electrode layer E4 includes the third plating layer. The fifth electrode layer E5 is formed on the fourth electrode layer E4 via a plating process. The fifth electrode layer E5 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 a configuration where the solder plating layer includes a Sn plating layer, the fifth electrode layer E5 includes Sn. The fifth electrode layer E5 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 fifth electrode layer E5 has, for example, a thickness of 4 to 8 μm.

[0032] Next, the inventors conducted the following tests to confirm that the multilayer capacitor C1 described above suppresses the decrease in insulation resistance. In these tests, the inventors prepared samples S1 to S33 with different configurations of the first electrode layer E1 and the second electrode layer E2, and confirmed the change in insulation resistance and thermal stress resistance in each sample S1 to S33. The test results are shown in Figures 3 and 4. Figures 3 and 4 are charts showing the test results for each sample.

[0033] Each sample S1 to S33 is a lot containing multiple samples. Each sample S1 to S33 is a multilayer capacitor with the same configuration except that the type of metal plating layer in the second electrode layer E2, the thickness of the first electrode layer E1 and the second electrode layer E2, and the sulfur (S) content in the first electrode layer E1 and the second electrode layer E2 differ. In samples S1 to S33, 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.

[0034] In sample S1, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S2, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains an In plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S3, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Zn plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S4, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains an Au plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S5, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains an Ag plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S6, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Cr plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S7, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Mn plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S8, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains an Fe plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S9, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Co plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S10, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S11, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains an In plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S12, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains a Zn plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S13, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains an Au plating layer and also has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%. In sample S14, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains an Ag plating layer and also has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%. In sample S15, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains a Cr plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S16, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains a Mn plating layer and also has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%. In sample S17, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains an Fe plating layer and also has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%. In sample S18, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains a Co plating layer and also has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%.

[0035] In sample S19, the second electrode layer E2 (Cu plating layer) has a thickness of 2.0 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 3.0 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%. In sample S20, the second electrode layer E2 (Cu plating layer) has a thickness of 3.0 μm, and the third electrode layer E3, which includes a Sn plating layer, has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is also 0.5 mol%. In sample S21, the second electrode layer E2 (Cu plating layer) has a thickness of 4.0 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S22, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.1 mol%. The sulfur (S) content in the third electrode layer E3 is 0.1 mol%. In sample S23, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.3 mol%. The sulfur (S) content in the third electrode layer E3 is 0.3 mol%. In sample S24, the second electrode layer E2 (Cu plating layer) has a thickness of 0.1 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 0.1 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S25, the second electrode layer E2 (Cu plating layer) has a thickness of 0.3 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 0.3 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S26, the second electrode layer E2 (Cu plating layer) has a thickness of 6.0 μm, and the third electrode layer E3 contains a Sn plating layer and has a thickness of 6.0 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S27, the external electrode 5 does not include the second electrode layer E2 and the third electrode layer E3. That is, the fourth electrode layer E4 is in contact with the first electrode layer E1. In sample S28, the second electrode layer E2 contains a Ni plating layer and has a thickness of 0.5 μm. The third electrode layer E3 also contains a Ni plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S29, the second electrode layer E2 contains a Ni plating layer and has a thickness of 4.5 μm. The third electrode layer E3 also contains a Ni plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S30, the second electrode layer E2 contains a Ni plating layer and has a thickness of 0.5 μm. The third electrode layer E3 contains a Sn plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S31, the second electrode layer E2 (Cu plating layer) has a thickness of 0.5 μm, and the third electrode layer E3 contains a Ni plating layer and has a thickness of 0.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S32, the second electrode layer E2 contains a Ni plating layer and has a thickness of 4.5 μm. The third electrode layer E3 contains a Sn plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%. In sample S33, the second electrode layer E2 (Cu plating layer) has a thickness of 4.5 μm, and the third electrode layer E3 contains a Ni plating layer and has a thickness of 4.5 μm. The sulfur (S) content in the second electrode layer E2 is 0.5 mol%. The sulfur (S) content in the third electrode layer E3 is 0.5 mol%.

[0036] Changes in insulation resistance are confirmed by the results of a moisture load test, which includes the following procedure. For each of the samples S1 to S33, 100 samples are selected and soldered onto a substrate (glass epoxy substrate). The substrate with the samples mounted is placed in a constant temperature and humidity chamber, and a predetermined voltage is applied to the samples mounted on the substrate 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 to be "defective". For each of the samples S1 to S33, the number of samples judged to be "defective" is counted. If the number of samples judged to be "defective" out of 100 samples is 15 or less, it is determined that the change in insulation resistance is suppressed.

[0037] Thermal stress tolerance is confirmed by the results of a thermal stress test that includes the following procedure. For each of the samples S1 to S33, 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 of the samples S1 to S33 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.

[0038] As a result of the tests described above, as shown in Figures 3 and 4, it was confirmed that the change in insulation resistance was suppressed in samples S1 to S26 compared to samples S27 to S33. In samples S1, S10, S19 to S23, and S26, it was confirmed that the change in insulation resistance was suppressed even further. In samples S3 and S5, although inferior to sample S1, it was confirmed that the change in insulation resistance was suppressed compared to samples S2, S4, and S6 to S9. Samples S1 to S23 were found to have better thermal stress resistance compared to sample S26. Samples S19 to S21 were found to have better thermal stress resistance compared to samples S10 to S18.

[0039] In the multilayer capacitor C1, the second electrode layer E2 and the third electrode layer E3 are located between the first electrode layer E1 and the fourth electrode layer E4. The second electrode layer E2 is a plating layer containing Cu. The third electrode layer E3 is a plating layer containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co. Therefore, the second electrode layer E2 and the third electrode layer E3 suppress the diffusion of hydrogen from the fourth electrode layer E4 to the first electrode layer E1. As a result, the multilayer capacitor C1 suppresses the decrease in insulation resistance.

[0040] The second electrode layer E2 and the third electrode layer E3 may each have a thickness of 0.5 μm or more. A configuration in which each of the second electrode layer E2 and the third electrode layer E3 has a thickness of 0.5 μm or more reliably suppresses a decrease in insulation resistance.

[0041] The second electrode layer E2 and the third electrode layer E3 may each have a thickness of 4.5 μm or less. The configuration in which each of the second electrode layer E2 and the third electrode layer E3 has a thickness of 4.5 μm or less reduces the stress acting on the substrate 3 from the second electrode layer E2 and the third electrode layer E3, even in environments where thermal stress is applied. Therefore, this configuration suppresses the occurrence of cracks in the substrate 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 layer E2 and the third electrode layer E3. Therefore, it is presumed that even if the third electrode layer E3 is a plating layer containing one metal other than Sn, selected from the group consisting of In, Zn, Au, Ag, Cr, Mn, Fe, and Co, the decrease in thermal stress resistance will be suppressed.

[0042] The combined thickness of the second electrode layer E2 and the third electrode layer E3 may be 5.0 to 8.5 μm. A configuration in which the combined thickness of the second electrode layer E2 and the third electrode layer E3 is 5.0 to 8.5 μm reliably suppresses the decrease in insulation resistance and the decrease in thermal stress resistance.

[0043] The ratio of the thickness of the second electrode layer E2 to the thickness of the third electrode layer E3 may be 2 / 3 to 8 / 9. A configuration in which the ratio of the thickness of the second electrode layer E2 to the thickness of the third electrode layer E3 is 2 / 3 to 8 / 9 reliably suppresses a decrease in insulation resistance and a decrease in thermal stress resistance.

[0044] The third electrode layer E3 may be a plating layer containing Sn. The configuration in which the third electrode layer E3 is a plating layer containing Sn further suppresses the decrease in insulation resistance.

[0045] In the multilayer capacitor C1, the second electrode layer E2 and the third electrode layer E3 may each contain 0.1 to 0.5 mol% of sulfur (S). Even when the second electrode layer E2 and the third electrode layer E3 each contain 0.1 to 0.5 mol% of sulfur (S), the decrease in insulation resistance is suppressed.

[0046] The multilayer capacitor C1 may include a fifth electrode layer E5. The multilayer capacitor C1, which includes the fifth electrode layer E5, offers excellent solderability.

[0047] The second electrode layer E2 and the third electrode layer E3 may each 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, the second electrode layer E2 and the third electrode layer E3, which include an electroplated layer, tend to have high adhesion to the second electrode layer E2 and the third electrode layer E3. In other words, the bonding and durability of the second electrode layer E2 are improved, and the bonding and durability of the third electrode layer E3 are improved. As a result, the second electrode layer E2 and the third electrode layer E3 further suppress the diffusion of hydrogen from the fourth electrode layer E4 to the first electrode layer E1. The configuration in which the second electrode layer E2 and the third electrode layer E3 include an electroplated layer further suppresses the decrease in insulation resistance.

[0048] 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.

[0049] 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.

[0050] In this embodiment, 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.

[0051] 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, Located on the aforementioned underlay electrode layer, a first plating layer containing Cu, A second plating layer located on the first plating layer and containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co, An electronic component comprising a third plating layer located on the second plating layer and containing Ni. (Note 2) The electronic component as described in Appendix 1, wherein each of the first plating layer and the second plating layer has a thickness of 0.5 μm or more. (Note 3) The electronic component as described in Appendix 2, wherein each of the first plating layer and the second plating layer has a thickness of 4.5 μm or less. (Note 4) The electronic component described in any one of the appendices 1 to 3, wherein the total thickness of the first plating layer and the second plating layer is 5.0 to 8.5 μm. (Note 5) The ratio of the thickness of the first plating layer to the thickness of the second plating layer is 2 / 3 to 8 / 9, as described in Appendix 4 for the electronic component. (Note 6) The aforementioned second plating layer is an electronic component containing Sn, as described in any one of Appendix 1 to 5. (Note 7) The aforementioned second plating layer is an electronic component as described in any one of the appendices 1 to 6, containing 0.1 to 0.5 mol% of S (sulfur). (Note 8) The electronic component according to any one of the appendices 1 to 7, wherein the outer conductor further includes a solder plating layer located on the third plating layer. [Explanation of Symbols]

[0052] 3...element body, 3e...side surface, 5...external electrode, 7...internal electrode, C1...multilayer capacitor, E1...first electrode layer, E2...second electrode layer, E3...third electrode layer, E4...fourth electrode layer, E5...fifth 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, Located on the aforementioned underlay electrode layer, a first plating layer containing Cu, A second plating layer located on the first plating layer and containing one metal selected from the group consisting of Sn, In, Zn, Au, Ag, Cr, Mn, Fe, and Co, An electronic component comprising a third plating layer located on the second plating layer and containing Ni.

2. The electronic component according to claim 1, wherein each of the first plating layer and the second plating layer has a thickness of 0.5 μm or more.

3. The electronic component according to claim 2, wherein each of the first plating layer and the second plating layer has a thickness of 4.5 μm or less.

4. The electronic component according to claim 1, wherein the total thickness of the first plating layer and the second plating layer is 5.0 to 8.5 μm.

5. The electronic component according to claim 4, wherein the ratio of the thickness of the first plating layer to the thickness of the second plating layer is 2 / 3 to 8 / 9.

6. The electronic component according to any one of claims 1 to 5, wherein the second plating layer contains Sn.

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

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 third plating layer.

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