Electronic component

Abstract

This electronic component comprises a base body and a first internal electrode and a second internal electrode, which are positioned inside the base body. The electronic component further includes a first external electrode and a second external electrode, which cover some of the outer surface of the base body and contain no silver component. The first external electrode comprises a first electrode (61A), which covers said some of the outer surface of the base body and is connected to the first internal electrode, and a second electrode (61B), which covers the outer surface (BD61A) of the first electrode (61A). The second electrode (61B) comprises copper particles (63) and a silicone resin (64) as a synthetic resin. When a specific section including the first electrode (61A) and the second electrode (61B) is observed, copper particles (63) contained in the second electrode (61B) are in linear contact with the outer surface (BD61A) of the first electrode (61A).

Description

Electronic Components

[0001] The present disclosure relates to electronic components.

[0002] The electronic component described in Patent Document 1 has an element body, internal electrodes, and external electrodes. The internal electrodes are located inside the element body. The external electrodes have an underlayer, a first plating layer, and a conductive resin layer. The underlayer covers a portion of the outer surface of the element body. The underlayer is primarily composed of metal and also contains a glass component. The first plating layer is located on the outer surface side of the underlayer. The first plating layer is made of copper. The conductive resin layer is located on the outer surface side of the first plating layer. The conductive resin layer is a resin layer containing silver. The electronic component described in Patent Document 1 also has a water-repellent organic compound on its outer surface.

[0003] Japanese Patent Application Laid-Open No. 2020-120100

[0004] In the electronic component described in Patent Document 1, the conductive resin layer contains a silver component. In a high-temperature, high-humidity environment, the silver contained in the conductive resin layer is likely to dissolve, which can cause migration. In this regard, the electronic component described in Patent Document 1 has a water-repellent organic compound on its surface. Therefore, this electronic component can prevent moisture from adhering to its surface and, ultimately, silver migration. However, providing such an organic compound layer may complicate the manufacturing process. Furthermore, the presence of such an organic compound layer may cause adverse effects. Therefore, there is a need for a technology that can suppress migration of external electrodes without requiring an additional layer, such as the organic compound layer of the electronic component described in Patent Document 1.

[0005] In order to solve the above problem, one aspect of the present disclosure is an electronic component comprising: an element body; an internal electrode located inside the element body; and an external electrode covering a portion of the outer surface of the element body and containing no silver components, wherein the external electrode has a first electrode covering a portion of the outer surface of the element body and connected to the internal electrode, and a second electrode covering the outer surface of the first electrode, wherein the second electrode contains copper particles and a synthetic resin, and when viewed in cross section at a specific cross section including the first electrode and the second electrode, the copper particles of the second electrode are in line contact with the outer surface of the first electrode.

[0006] According to the above configuration, since the external electrodes do not contain a silver component, migration can be suppressed from occurring in the external electrodes.

[0007] FIG. 1 is a perspective view of an electronic component. FIG. 2 is a side view of the electronic component. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2. FIG. 4 is a cross-sectional view of a specific cross section of the electronic component. FIG. 5 is a schematic enlarged view of a portion of FIG. 4. FIG. 6 is a flowchart illustrating a method for manufacturing an electronic component.

[0008] An embodiment of an electronic component will be described below with reference to the drawings. Note that the drawings may show components enlarged to facilitate understanding. The dimensional proportions of the components may differ from those in the actual drawings or from those in other drawings.

[0009] <Overall Configuration of Electronic Component> As shown in FIG. 1 , the electronic component 10 is a multilayer ceramic capacitor. The electronic component 10 includes an element body 20. The element body 20 is generally rectangular prism-shaped and has a central axis CA. In the following description, an axis extending along the central axis CA is referred to as a first axis X. One of the axes perpendicular to the first axis X is referred to as a second axis Y. An axis perpendicular to the first axis X and the second axis Y is referred to as a third axis Z. In addition, one of the directions along the first axis X is referred to as a first positive direction X1, and the direction along the first axis X that is opposite to the first positive direction X1 is referred to as a first negative direction X2. One of the directions along the second axis Y is referred to as a second positive direction Y1, and the direction along the second axis Y that is opposite to the second positive direction Y1 is referred to as a second negative direction Y2. Furthermore, one of the directions along the third axis Z is defined as a third positive direction Z1, and the direction along the third axis Z opposite to the third positive direction Z1 is defined as a third negative direction Z2.

[0010] The outer surface 21 of the element body 20 has six flat surfaces. The term "surface" of the element body 20 used here refers to a surface that can be observed when the entire element body 20 is observed. In other words, even if there are minute irregularities or steps that are not visible unless a portion of the element body 20 is magnified and observed using a microscope, the surface is still referred to as a flat or curved surface. The six flat surfaces face in different directions. The six flat surfaces are broadly divided into a first end surface 22A facing the first positive direction X1, a second end surface 22B facing the first negative direction X2, and four side surfaces 22C. The four side surfaces 22C are, respectively, a surface facing the third positive direction Z1, a surface facing the third negative direction Z2, a surface facing the second positive direction Y1, and a surface facing the second negative direction Y2.

[0011] The boundary portions between two adjacent flat surfaces and the boundary portions between three adjacent surfaces of the outer surface 21 of the element body 20 are curved. That is, the corners of the element body 20 are rounded and chamfered.

[0012] 1 and 2, the element body 20 has a dimension along the first axis X that is larger than the dimensions along the third axis Z and the dimensions along the second axis Y. The material of the element body 20 is a dielectric ceramic. Specifically, the material of the element body 20 is BaTiO ３ The main component of the element 20 is CaTiO ３ , SrTiO ３, CaZrO ３ The material of the element body 20 may contain, as a secondary component, a Mn compound, a Co compound, a Si compound, a rare earth compound, or the like.

[0013] 3 , the electronic component 10 includes four first internal electrodes 41 and four second internal electrodes 42. The first internal electrodes 41 and the second internal electrodes 42 are located inside the element body 20.

[0014] The material of the first internal electrode 41 is a conductive material. For example, the material of the first internal electrode 41 is Ni. The material of the first internal electrode 41 may further include a metal such as Ni, Cu, Ag, Au, Pt, Sn, or Pd, or an alloy containing these metals. The material of the second internal electrode 42 is the same as the material of the first internal electrode 41.

[0015] The first internal electrode 41 has a rectangular plate shape. The main surface of the first internal electrode 41 is perpendicular to the second axis Y. The second internal electrode 42 has the same rectangular plate shape as the first internal electrode 41. The main surface of the second internal electrode 42 is perpendicular to the second axis Y, similar to the first internal electrode 41.

[0016] The dimension of the first internal electrode 41 in the direction along the first axis X is smaller than the dimension of the element body 20 in the direction along the first axis X. Also, as shown in Fig. 1 , the dimension of the first internal electrode 41 in the direction along the third axis Z is approximately two-thirds of the dimension of the element body 20 in the direction along the third axis Z. The dimensions of the second internal electrode 42 in each direction are the same as those of the first internal electrode 41.

[0017] 3, the first internal electrodes 41 and the second internal electrodes 42 are positioned alternately in the direction along the second axis Y. That is, a total of eight internal electrodes are arranged alternately in the order of the first internal electrodes 41 and the second internal electrodes 42 from the side surface 22C facing the second positive direction Y1 toward the second negative direction Y2. In this embodiment, the distances between the respective internal electrodes in the direction along the second axis Y are equal.

[0018] As shown in Fig. 1, the four first internal electrodes 41 and the four second internal electrodes 42 are all located at the center of the element body 20 in the direction along the third axis Z. On the other hand, as shown in Fig. 3, the first internal electrodes 41 are located closer to the first positive direction X1, and the second internal electrodes 42 are located closer to the first negative direction X2.

[0019] Specifically, the end of the first internal electrode 41 on the first positive direction X1 side substantially coincides with the end of the element body 20 on the first positive direction X1 side. Therefore, the end of the first internal electrode 41 on the first positive direction X1 side is exposed from the first end surface 22A of the element body 20. The end of the first internal electrode 41 on the first negative direction X2 side is located inside the element body 20 and does not reach the end of the element body 20 on the first negative direction X2 side. On the other hand, the end of the second internal electrode 42 on the first negative direction X2 side substantially coincides with the end of the element body 20 on the first negative direction X2 side. Therefore, the end of the second internal electrode 42 on the first negative direction X2 side is exposed from the second end surface 22B of the element body 20. The end of the second internal electrode 42 on the first positive direction X1 side is located inside the element body 20 and does not reach the end of the element body 20 on the first positive direction X1 side.

[0020] As shown in FIG. 3 , the electronic component 10 includes a first external electrode 61 and a second external electrode 62. The first external electrode 61 and the second external electrode 62 are conductive as a whole. However, the first external electrode 61 and the second external electrode 62 do not contain silver. Here, "does not contain silver" means that a small amount of silver may be mixed into each external electrode during the manufacturing process. For example, if the atomic percentage of silver atoms relative to the total atoms constituting each external electrode is less than 1 atm %, the "external electrode does not contain silver." This is because, if the atomic percentage of silver atoms is less than 1 atm %, significant migration that would affect the characteristics of the electronic component 10 does not occur.

[0021] The first external electrode 61 has a first electrode 61A, a second electrode 61B, and a third electrode 61C. The first electrode 61A covers a portion of the outer surface 21 of the element body 20. Specifically, the first electrode 61A covers a first end face 22A of the element body 20 and portions of the four side faces 22C facing the first positive direction X1. The first electrode 61A is also connected to the first internal electrode 41 exposed from the first end face 22A. The first electrode 61A contains a copper component and a trace amount of glass.

[0022] The second electrode 61B covers the outer surface BD61A of the first electrode 61A. That is, the second electrode 61B is stacked on the first electrode 61A. Details of the second electrode 61B will be described later.

[0023] The third electrode 61C covers the outer surface BD61B of the second electrode 61B. A portion of the third electrode 61C protrudes from the second electrode 61B. Although not shown, the third electrode 61C has a two-layer structure including, in order from the second electrode 61B side, a nickel layer and a tin layer.

[0024] The second external electrode 62 has a first electrode 62A, a second electrode 62B, and a third electrode 62C. The first electrode 62A covers a portion of the outer surface 21 of the element body 20. Specifically, the first electrode 62A covers the second end face 22B of the element body 20 and portions of the four side faces 22C facing the first negative direction X2. The first electrode 62A is connected to the second internal electrode 42 exposed from the second end face 22B. The material of the first electrode 62A is the same as the material of the first electrode 61A of the first external electrode 61.

[0025] 3, the second electrode 62B covers the outer surface BD62A of the first electrode 62A. Details of the second electrode 62B will be described later. The third electrode 62C covers the outer surface BD62B of the second electrode 62B. A portion of the third electrode 62C protrudes from the second electrode 62B. Although not shown, the third electrode 62C has a two-layer structure consisting of, in order from the second electrode 62B side, a nickel layer and a tin layer.

[0026] The second external electrode 62 does not reach the first external electrode 61 on the side surface 22C, and is spaced apart from the first external electrode 61 in the direction along the first axis X. The first external electrode 61 and the second external electrode 62 are not stacked in the central portion of the side surface 22C of the element body 20 in the direction along the first axis X. In FIGS. 1 to 3, the first external electrode 61 and the second external electrode 62 are shown by two-dot chain lines.

[0027] <Regarding the Second Electrode> The configuration of the second electrode 61B will be described. Note that, although the following description will be given focusing on the second electrode 61B of the first external electrode 61, the same applies to the second electrode 62B of the second external electrode 62.

[0028] As shown in Fig. 5, the second electrode 61B is a sintered body containing copper. Specifically, the second electrode 61B contains copper particles 63. Note that in Fig. 5, only some of the copper particles 63 are labeled with reference numerals. Furthermore, although each copper particle 63 is illustrated as being substantially circular, it may be an oval or other irregularly shaped particle.

[0029] Furthermore, the second electrode 61B contains, in addition to the copper particles 63, a silicone resin 64 as a synthetic resin. The silicone resin 64 contains Si. The silicone resin 64 is a polymer formed from a siloxane bond and a Si—C bond. The silicone resin 64 is distributed in a network pattern. Specifically, when the second electrode 61B is viewed in cross section, the silicone resin 64 is distributed in a network pattern so as to fill the spaces between the multiple copper particles 63.

[0030] As shown in FIG. 4 , the average thickness H of the second electrode 61B is approximately 700 nm. The thickness H of the second electrode 61B is the shortest distance from the outer surface BD61A of the first electrode 61A to the outer surface BD61B of the second electrode 61B. Note that FIG. 4 illustrates the thickness H at one arbitrary location. The average thickness H of the second electrode 61B is calculated as follows: First, an arbitrary cross-section of the second electrode 61B is photographed using an electron microscope. Next, a range in the photographed image in the direction along the outer surface BD61B of the second electrode 61B is identified. Within this range, the cross-sectional area of ​​the second electrode 61B is calculated by image processing for a measurement range of at least 5 μm or more. The average thickness H of the second electrode 61B is then calculated by dividing the cross-sectional area of ​​the second electrode 61B in the calculated measurement range by the length of the measurement range.

[0031] The second electrode 61B contains a chemical component that is not contained in the second electrode 61B but is contained only in the first electrode 61A. Specifically, the chemical component is a glass component that is a constituent of the first electrode 61A. The glass component is distributed throughout substantially the entire second electrode 61B.

[0032] The second electrode 61B contains a chemical component that is not contained in the second electrode 61B but is contained only in the third electrode 61C. Specifically, the chemical component is a nickel component that is a constituent component of the third electrode 61C. Note that the nickel component may reach the first electrode 61A.

[0033] <Contact State Between First Electrode and Second Electrode> As shown in FIG. 5 , the electronic component 10 is viewed in cross section at a specific cross section including the first electrode 61A and the second electrode 61B. The specific cross section is, for example, a cross section perpendicular to the central axis CA of the element body 20. In this case, the copper particles 63 of the second electrode 61B are in line contact with the outer surface BD61A of the first electrode 61A. Note that at this contact point, the copper particles 63 and the copper component of the first electrode 61A may be integrated, and no boundary may exist between the two copper components. If the boundary with the copper particles 63 cannot be observed, the line connecting the ends of the contact point with the copper particles 63 is taken as the outer surface BD61A of the first electrode 61A.

[0034] Copper particles 63 in line contact with the outer surface BD61A of first electrode 61A have spherical portions BP and columnar portions PP. The columnar portions PP extend from the spherical portions BP facing the first electrode 61A toward the first electrode 61A. This is because a portion of copper particle 63 melts during the manufacturing process and becomes integrated with the outer surface BD61A of first electrode 61A.

[0035] In a specific cross section, the columnar portion PP may have a substantially rectangular shape, a substantially trapezoidal shape whose width increases toward the outer surface BD61A, or a substantially trapezoidal shape whose width decreases toward the outer surface BD61A, provided that the maximum width of the columnar portion PP is smaller than the particle diameter of the spherical portion BP.

[0036] In a specific cross section, the contact length L of the copper particles 63 in line contact with the first electrode 61A is 5 nm or more. The contact length L is measured as follows. First, in the specific cross section, the outlines of the copper particles 63 and the outer surface BD61A of the first electrode 61A are obtained by image processing using an electron microscope. Then, the number of copper particles 63 in contact with the outer surface BD61A within a continuous range of 50 nm or more on the outer surface BD61A is counted. In addition, the total value of the contact lengths L of the copper particles 63 in contact with the outer surface BD61A within the same range is measured. The value obtained by dividing this total value by the number of copper particles 63 counted is defined as the contact length L of each copper particle 63 with the first electrode 61A. It is preferable to measure the contact length L of the copper particles 63 at multiple cross sections, for example, five or more cross sections, of one electronic component 10, at two or more locations on each cross section, and use the average of the measured values ​​as the final contact length L of the copper particles 63.

[0037] In addition, in this embodiment, the average particle size of the copper particles 63 is 50 nm or more and 100 nm or less. The average particle size of the copper particles 63 is determined as follows. First, the outline of the copper particles 63 is obtained by image processing using an electron microscope. Then, the area of ​​one copper particle 63 is calculated. Then, a circle having the calculated area is assumed. The diameter of the circle is calculated as the particle size of the copper particle 63. In this manner, particle sizes are calculated for 10 or more copper particles 63, and the average value is set as the average particle size. As described above, in this embodiment, the contact length L of the copper particle 63 with the outer surface BD61A of the first electrode 61A is 10 nm or more. In this embodiment, the contact length L of the copper particle 63 with the first electrode 61A is 10% or more of the average particle size of the copper particles 63.

[0038] <Method for Manufacturing Electronic Component> Next, a description will be given of a method for manufacturing electronic component 10. As shown in Fig. 6, the method for manufacturing electronic component 10 includes a laminate preparation step S11, an R-chamfering processing step S12, a conductor application step S13, a curing step S14, and a plating step S15.

[0039] First, in forming the element body 20, a laminate is prepared in the laminate preparation step S11. The laminate at this stage is in a state before R-chamfering and is a rectangular parallelepiped with six flat surfaces. Specifically, for example, first, a plurality of ceramic sheets that will become the element body 20 are prepared. The sheets are thin plates. A conductive paste that will become the first internal electrode 41 is laminated on the sheets. A ceramic sheet that will become the element body 20 is laminated on the paste. A conductive paste that will become the second internal electrode 42 is laminated on the sheets. In this manner, the ceramic sheets and the conductive paste are laminated alternately. The laminated sheets are then compressed in the stacking direction using a mold press or other means. The compressed sheet is then cut to a predetermined size to form an unfired laminate. The unfired laminate is then fired at a high temperature to prepare the laminate.

[0040] Next, an R-chamfering process step S12 is performed. In the R-chamfering process step S12, the laminate prepared in the laminate preparation process S11 is R-chamfered. This process provides an element body 20 with R-chamfered corners.

[0041] Next, a conductor application step S13 is performed. In the conductor application step S13, a first conductor paste is applied to a portion of the first end face 22A of the element body 20 and a portion of the second end face 22B of the element body 20 by a dip method. Specifically, the first conductor paste is applied so as to cover the entire first end face 22A and portions of the four side faces 22C. The first conductor paste is also applied so as to cover the entire second end face 22B and portions of the four side faces 22C. The first conductor paste contains a copper component and a silicon component.

[0042] Furthermore, in the conductor application step S13, a second conductor paste is applied onto the first conductor paste in two locations. The second conductor paste is a complex ink. The second conductor paste is prepared as follows: First, an amine compound such as 2-ethylhexylamine is mixed with an alcohol amine such as 2-amino-2-methylpropanol. Then, a silicon component such as silicone resin is added at 0.001-10 wt % relative to the weight of Cu alone. Then, a metal salt is further added and dissolved to prepare the second conductor paste. The sintering start temperature of the copper component is 170°C, and the hardening start temperature of the silicon component is 250°C.

[0043] Next, a curing step S14 is performed. Specifically, in the curing step S14, the element body 20 coated with the first and second conductive pastes is heated. In this embodiment, the element body 20 coated with the first and second conductive pastes is heated in a nitrogen atmosphere. The temperature is then maintained at a range of 300 to 600 degrees Celsius. This causes the first and second conductive pastes to be fired. During the firing of the second conductive paste, sintering of the copper component contained in the second electrodes 61B and 62B begins first. When sintering of the copper component begins, the silicon component is not hardened and remains fluid. Therefore, the silicon component fills the gaps between the copper components. After sintering of the copper component begins, when the temperature further rises to the hardening initiation temperature of the silicon component, hardening of the silicon component contained in the second electrodes 61B and 62B begins. In other words, the hardening initiation temperature of the silicon component is higher than the sintering initiation temperature of the copper component. The copper component is sintered to produce copper particles 63. The silicon component is hardened to produce silicone resin 64. As described above, the hardening start temperature of the silicon component is higher than the sintering start temperature of the copper component, and therefore the silicone resin 64 becomes a mesh-like structure that fills the gaps between the copper particles 63. As a result, the second electrode 61B and the second electrode 62B are formed as described above.

[0044] In the curing step S14, the copper component in the second conductive paste has high surface free energy. Therefore, the copper component in the second conductive paste is adsorbed to the copper component in the first conductive paste to reduce the surface area. As a result, the copper particles 63 are in line contact with the first electrode 61A at the specific cross section.

[0045] Next, a plating step S15 is performed. Electroplating is performed on the locations where the second electrodes 61B and 62B are located. As a result, a third electrode 61C is formed on the surface of the second electrode 61B. Also, a third electrode 62C is formed on the surface of the second electrode 62B. Although not shown, the third electrodes 61C and 62C are electroplated with two types of metal, nickel and tin, to form a two-layer structure. In this manner, the electronic component 10 is formed.

[0046] <Effects of this embodiment> The effects of this embodiment will be described below. Note that, although the effects relating to the first external electrode 61 will be described as a representative example, the second external electrode 62 also provides similar effects.

[0047] (1) According to the above configuration, because the first external electrode 61 does not contain a silver component, migration in the first external electrode 61 can be suppressed. Furthermore, because the second electrode 61B contains copper particles 63, some of the copper particles 63 fall off when an external force is applied to the second electrode 61B. Therefore, the entire second electrode 61B is unlikely to peel off from the first electrode 61A. Furthermore, if all of the copper particles 63 fall off when an external force is applied to the second electrode 61B, electrical connection between the second electrode 61B and the first electrode 61A may be lost. On the other hand, because the copper particles 63 are in line contact with the outer surface BD61A of the first electrode 61A, good conductivity between the first electrode 61A and the second electrode 61B can be ensured. Thus, according to the above configuration, migration can be suppressed while maintaining suitable mechanical strength and conductivity, which are characteristics suitable for an external electrode.

[0048] (2) In the above embodiment, the contact length L of the copper particles 63 in line contact with the first electrode 61A in the specific cross section is 5 nm or more. Because the copper particles 63 are in line contact with the first electrode 61A with the above dimensions, the second electrode 61B is less likely to peel off from the first electrode 61A.

[0049] (3) In the above embodiment, the contact length L of the copper particles 63 that are in line contact with the first electrode 61A in the specific cross section is equal to or greater than 10% of the average particle size of the copper particles 63. By having the copper particles 63 in line contact with the first electrode 61A at such a dimension, the copper particles 63 are less likely to peel off from the first electrode 61A, and the adhesive force of the second electrode 61B to the first electrode 61A is ensured.

[0050] (4) In the above embodiment, the second electrode 61B contains silicone resin 64 as the synthetic resin. That is, the synthetic resin contained in the second electrode 61B contains Si. When the synthetic resin contains Si, the surface tension of the synthetic resin is easily maintained between the copper particles 63 during manufacturing. As a result, in the formed second electrode 61B, the synthetic resin becomes a dense film that fills the gaps between the copper particles 63. As a result, the barrier properties of the second electrode 61B are improved.

[0051] (5) In the above embodiment, the second electrode 61B contains a chemical component that is not contained in the second electrode 61B but is contained only in the first electrode 61A. With this configuration, at least a portion of the second electrode 61B is integrated with the first electrode 61A. As a result, the second electrode 61B is less likely to peel off from the first electrode 61A.

[0052] The second electrode 61B contains a chemical component that is not contained in the second electrode 61B but is contained only in the third electrode 61C. With this configuration, at least a portion of the second electrode 61B is integrated with the third electrode 61C. As a result, the third electrode 61C is less likely to peel off from the second electrode 61B.

[0053] (6) In the above embodiment, the first electrode 61A contains a copper component. With this configuration, the copper particles 63 contained in the second electrode 61B are likely to be integrated with the copper component contained in the first electrode 61A during the manufacturing process. Therefore, since many of the copper particles 63 are in line contact with the first electrode 61A, it is expected that the adhesive strength of the second electrode 61B to the first electrode 61A will be improved.

[0054] <Modifications> The above embodiment and the following modifications can be implemented in combination with each other to the extent that no technical contradiction occurs. In the case of a modification that can be commonly applied to the first external electrode 61 and the second external electrode 62, the modification related to the first external electrode 61 will be described as a representative example.

[0055] In the above embodiment, the electronic component 10 is not limited to a multilayer ceramic capacitor. For example, the electronic component 10 may be a piezoelectric component, a thermistor, an inductor, etc. In the above embodiment, the material of the element body 20 may be a dielectric, a piezoelectric material, a magnetic material such as ferrite, a composite of synthetic resin and metal, etc.

[0056] The shape of the element body 20 is not limited to the example in the above embodiment. For example, the element body 20 may be a polygonal columnar shape other than a quadrangular columnar shape having a central axis CA. The element body 20 may also be the core of a wire-wound inductor component. For example, the core may have a so-called drum core shape. Specifically, the core may have a columnar winding core portion and flange portions provided at each end of the winding core portion.

[0057] The boundary portion between adjacent flat surfaces on the outer surface 21 of the element body 20 does not have to be chamfered. In this case, there is no curved surface at the boundary portion. The shapes of the first internal electrodes 41 and second internal electrodes 42 are not important as long as they ensure electrical conduction with the corresponding first external electrodes 61 and second external electrodes 62. Furthermore, the number of first internal electrodes 41 and second internal electrodes 42 is not important and may be more or less than four.

[0058] In the above embodiment, the material of the first electrode 61A is not limited to the example in the above embodiment. That is, the first electrode 61A does not have to contain a copper component. For example, the material of the first electrode 61A may be a metal such as Ni, Pd, or Au, or may contain any of these metals.

[0059] In the above embodiment, it is sufficient that the second electrode 61B covers at least a portion of the first electrode 61A. In the above embodiment, the average value of the thickness H of the second electrode 61B is not limited to the example in the above embodiment. The overall thickness of the first external electrode 61, including the second electrode 61B, may be designed taking into account the mechanical strength required of the electronic component 10, etc.

[0060] In the above embodiment, the configuration related to the third electrode 61C may be omitted from the first external electrode 61. Furthermore, the material of the third electrode 61C is not limited to the example in the above embodiment. For example, the third electrode 61C may be made of only nickel, only tin, or may contain a material other than silver.

[0061] In the above embodiment, the synthetic resin is not limited to the silicone resin 64. For example, the synthetic resin may be a synthetic resin containing Si, such as a silicone oligomer. The synthetic resin contained in the second electrode 61B may also contain N. For example, the synthetic resin may be a synthetic resin containing N, such as urethane, epoxy, polyimide, polyimide amide, or polyamide. In this way, when the synthetic resin contains N, the heat resistance of the second electrode 61B is improved.

[0062] The synthetic resin is not limited to resins containing N and Si, and may be acrylic, alkyd, polyester, or other synthetic resins. The second electrode 61B may be made of a composite of these N-containing synthetic resins, Si-containing synthetic resins, and other synthetic resins. The second electrode 61B may be made of a single synthetic resin containing Si and N.

[0063] In the above embodiment, the contact length L of the copper particles 63 in line contact with the first electrode 61A is not limited to the example of the above embodiment. For example, in a specific cross section, the contact length L of the copper particles 63 in line contact with the first electrode 61A may be less than 5 nm as long as electrical conduction with the first electrode 61A is ensured. Similarly, in a specific cross section, the contact length L of the copper particles 63 in line contact with the first electrode 61A may be less than 10% of the average particle size of the copper particles 63. Note that the average particle size of the copper particles 63 in the above embodiment is also not limited to the example of the above embodiment.

[0064] In the above embodiment, the second electrode 61B may not contain a chemical component that is not contained in the second electrode 61B and is contained only in the first electrode 61A. That is, the boundary between the second electrode 61B and the first electrode 61A may be clearly defined. Furthermore, the second electrode 61B may not contain a chemical component that is not contained in the second electrode 61B and is contained only in the third electrode 61C. That is, the boundary between the second electrode 61B and the third electrode 61C may be clearly defined.

[0065] The manufacturing process of the electronic component 10 in the above embodiment is not limited to the example of the above embodiment. For example, the element body 20 may be subjected to a process such as physical polishing. In the above embodiment, the method for applying the first conductive paste and the second conductive paste is not limited to the example of the above embodiment. For example, these pastes may be applied by printing, or may be applied by an inkjet method or the like. Furthermore, the first conductive paste and the second conductive paste may be applied by different methods.

[0066] In the above embodiment, the curing step S14 may be performed in multiple steps. That is, the firing may be performed in multiple steps. In the above embodiment, the sintering start temperature of the copper component of the second conductive paste and the curing start temperature of the silicon component are not limited to the examples in the above embodiment.

[0067] In the above embodiment, the second conductive paste may be nanoink. Nanoink is prepared as follows: Nanometal powder is dispersed in a solvent containing cellosolves, carbitols, hydrocarbons, aromatics, or the like. Then, various silicone-modified resins, silicone resins, sol-gel materials, or the like are added in an amount of 0.001-10 wt % relative to the weight of Cu alone. The nanoink second conductive paste may be prepared in this manner, or a different method may be used.

[0068] In the above embodiment, the material used when the second conductive paste is a complex ink is not limited to the example of the above embodiment. For example, the amine compound may be a primary amine, secondary amine, or tertiary amine, and the number of N atoms is not limited. For example, it may be a primary amine such as octylamine or hexylamine, a secondary amine such as di-n-butylamine, or a tertiary amine such as N,N-dimethylhexylamine. The amine compound may also be an alcohol amine or a diamine, and the positional relationship between the N atom and the OH group is not limited to the α, β, or γ position. Furthermore, the number of N and O atoms in one molecule is not particularly limited. For example, it may be an α-hydroxyamine such as 2-dimethylaminoethanol or 2-ethylaminoethanol, or a β-hydroxyamine such as 3-amino-1-propanol or 4-amino-2-butanol. Furthermore, it may be a diamine such as ethylenediamine, or a cyclic diamine such as piperazine. The silicon component may be, for example, various silicone-modified resins such as epoxy resins, polyester resins, and phenolic resins, or a sol-gel material. Furthermore, metal salts made of formic acid, acetic acid, oxalic acid, other organic acids, etc., may also be used as the metal salts. An example of this type of metal salt is anhydrous copper formate.

[0069] In the above embodiment, the electronic component 10 may include a glass film. In this case, for example, the glass film may be formed so as to cover a partial region of the outer surface 21 of the element body 20. In other words, even if a glass film covering the element body 20 is present, it is sufficient that the electrical connection between the first internal electrode 41 and the first external electrode 61, and the electrical connection between the second internal electrode 42 and the second external electrode 62 are ensured.

[0070] <Supplementary Notes> The technical concepts that can be derived from the above embodiments and modified examples are described below. [1] An electronic component comprising an element body, an internal electrode located inside the element body, and an external electrode covering a portion of the outer surface of the element body and containing no silver component, wherein the external electrode has a first electrode covering a portion of the outer surface of the element body and connected to the internal electrode, and a second electrode covering the outer surface of the first electrode, the second electrode containing copper particles and a synthetic resin, and when viewed in cross section at a specific cross section including the first electrode and the second electrode, the copper particles of the second electrode are in line contact with the outer surface of the first electrode.

[0071] [2] The electronic component according to [1], wherein the contact length between the copper particles that are in line contact with the first electrode in the specific cross section and the first electrode is 5 nm or more. [3] The electronic component according to [1] or [2], wherein the contact length between the copper particles that are in line contact with the first electrode in the specific cross section and the first electrode is 10% or more of the average particle size of the copper particles.

[0072] [4] The electronic component according to any one of [1] to [3], wherein the synthetic resin contained in the second electrode contains Si. [5] The electronic component according to any one of [1] to [4], wherein the synthetic resin contained in the second electrode contains N.

[0073] [6] The electronic component according to any one of [1] to [5], wherein the external electrode further includes a third electrode covering the outer surface of the second electrode, the second electrode containing a chemical component that is not contained in the second electrode but is contained only in the first electrode, and the second electrode containing a chemical component that is not contained in the second electrode but is contained only in the third electrode.

[0074] [7] The electronic component according to any one of [1] to [6], wherein the first electrode contains a copper component.

[0075] REFERENCE SIGNS LIST 10... Electronic component 20... Body 21... Outer surface 41... First internal electrode 42... Second internal electrode 61... First external electrode 61A... First electrode 61B... Second electrode 61C... Third electrode 63... Copper particles 64... Silicone resin

Claims

1. The body and An internal electrode located inside the element body; an external electrode that covers a portion of an outer surface of the element body and does not contain a silver component; Equipped with the external electrode includes a first electrode covering a portion of an outer surface of the element body and connected to the internal electrode, and a second electrode covering an outer surface of the first electrode; The second electrode contains copper particles and a synthetic resin, When viewed in cross section at a specific cross section including the first electrode and the second electrode, the copper particles of the second electrode are in line contact with an outer surface of the first electrode, The first electrode and the second electrode both contain a glass component. Electronic components.

2. In the specific cross section, the contact length between the copper particles that are in line contact with the first electrode and the first electrode is 5 nm or more. The electronic component according to claim 1 .

3. In the specific cross section, a contact length between the copper particles that are in line contact with the first electrode and the first electrode is 10% or more of an average particle size of the copper particles. The electronic component according to claim 1 .

4. The synthetic resin contained in the second electrode contains Si. The electronic component according to claim 1 .

5. The synthetic resin contained in the second electrode contains N. The electronic component according to claim 1 .

6. The first electrode contains a copper component. The electronic component according to claim 1 .

7. The body and An internal electrode located inside the element body; an external electrode that covers a portion of an outer surface of the element body and does not contain a silver component; Equipped with the external electrode includes a first electrode covering a portion of an outer surface of the element body and connected to the internal electrode, and a second electrode covering an outer surface of the first electrode; The second electrode contains copper particles and a synthetic resin, When viewed in cross section at a specific cross section including the first electrode and the second electrode, the copper particles of the second electrode are in line contact with an outer surface of the first electrode, the external electrode further includes a third electrode covering an outer surface of the second electrode, the second electrode contains a chemical component that is not contained in the second electrode and is contained only in the first electrode; The second electrode contains a chemical component that is not contained in the second electrode and is contained only in the third electrode. Electronic components.