Electronic components and mounting structures for electronic components

Abstract

This electronic component comprises: an element body; a first internal electrode; and a first external electrode (61). The first internal electrode is located inside the element body. The first outer electrode (61) covers a section of the outer surface of the element body. The first outer electrode (61) includes: a first electrode (61A) that covers a section of the outer surface of the element body and connects to the first internal electrode: and a second electrode (61B) that covers the outer surface of the first electrode (61A). The second electrode (61B) includes spherical copper particles (63) and silicon.

Description

[Technical Field]

[0001] The present disclosure relates to an electronic component and a mounting structure for an electronic component. [Background Art]

[0002] The electronic component described in Patent Document 1 includes an element body, an internal electrode, a dummy internal electrode, and an external electrode. The internal electrode and the dummy internal electrode are located inside the element body. The external electrode covers a part of the outer surface of the element body. Further, the external electrode is connected to the internal electrode. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2015-115518 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] Mechanical external impacts or thermal stress caused by temperature changes may act on the electronic component described in Patent Document 1. Accordingly, cracks or the like may occur in the element body of the electronic component. The electronic component described in Patent Document 1 attempts to suppress the occurrence of cracks in the element body through the internal structure of the element body such as the dummy internal electrode. On the other hand, no consideration has been given to the relationship between the external electrode and cracks or chips in the element body. [Means for Solving the Problem]

[0005] In order to solve the above problem, one aspect of the present disclosure is an electronic component including: an element body; an internal electrode located inside the element body; and an external electrode covering a part of the outer surface of the element body, wherein the external electrode has a first electrode that covers a part of the outer surface of the element body and is connected to the internal electrode, and a second electrode that covers the outer surface of the first electrode, and the second electrode includes spherical copper particles and silicon.

[0006] Furthermore, in order to solve the above problems, one aspect of the present disclosure is an electronic component mounting structure comprising a substrate and an electronic component mounted on the substrate, wherein the electronic component comprises a body, an internal electrode located inside the body, and an external electrode covering a part of the outer surface of the body, the external electrode having a first electrode covering a part of the outer surface of the body and connected to the internal electrode, and a second electrode covering the outer surface of the first electrode, the second electrode having spherical copper particles and silicon, and when the outer surface of the body facing the substrate is considered the mounting surface, the first electrode covers at least a part of the mounting surface, and the second electrode covers at least the outer surface of the portion of the outer surface of the first electrode that covers the mounting surface.

[0007] According to the above configuration, the second electrode has a structure in which spherical copper particles are dispersed in silicon. As a result, the bending strength of the second electrode is relatively small. Therefore, when external forces such as impact and thermal stress are applied to the electronic component, the second electrode is more likely to deform and crack before the main body. In other words, the second electrode plays a role in mitigating the effects of external forces by breaking itself. Therefore, when an external force is applied to the electronic component, cracks are less likely to occur in the main body. Even if the second electrode is damaged, the internal electrode remains connected to the first electrode. Therefore, conductivity between the external electrode and the internal electrode is ensured. [Effects of the Invention]

[0008] External electrodes can suppress cracks and other damage to the base material. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a perspective view of an electronic component. [Figure 2] Figure 2 is a side view of an electronic component. [Figure 3] Figure 3 is a cross-sectional view along the line 3-3 in Figure 2. [Figure 4] Figure 4 is a schematic diagram of an enlarged cross-section of the first external electrode of an electronic component. [Figure 5] Figure 5 is a schematic diagram of an enlarged cross-section of the first external electrode of an electronic component. [Figure 6] Figure 6 is a flowchart illustrating the manufacturing method of electronic components. [Figure 7] Figure 7 shows the mounting structure including the modified electronic components and circuit board. [Figure 8] Figure 8 shows the mounting structure including the modified electronic components and circuit board. [Figure 9] Figure 9 is a cross-sectional view of the modified electronic components and circuit board. [Figure 10] Figure 10 is a cross-sectional view of the modified electronic components and circuit board. [Modes for carrying out the invention]

[0010] Hereinafter, an embodiment of an electronic component and its mounting structure will be described with reference to the drawings. Note that the drawings may show components enlarged for ease of understanding. The dimensional ratios of the components may differ from those in the actual drawings or those shown in other drawings.

[0011] <Overall configuration of electronic components> As shown in Figure 1, the electronic component 10 is a multilayer ceramic capacitor. The electronic component 10 comprises a base body 20. The base body 20 is roughly rectangular in shape and has a central axis CA. In the following, the axis extending along the central axis CA will be referred to as the first axis X. One of the axes perpendicular to the first axis X will be referred to as the second axis Y. The axis perpendicular to both the first axis X and the second axis Y will be referred to as the third axis Z. In addition, one direction along the first axis X will be referred to as the first positive direction X1, and the direction along the first axis X opposite to the first positive direction X1 will be referred to as the first negative direction X2. Furthermore, one direction along the second axis Y will be referred to as the second positive direction Y1, and the direction along the second axis Y opposite to the second positive direction Y1 will be referred to as the second negative direction Y2. Furthermore, one direction along the third axis Z is defined as the third positive direction Z1, and the direction along the third axis Z opposite to the third positive direction Z1 is defined as the third negative direction Z2.

[0012] The outer surface 21 of the element body 20 has six flat surfaces 22. The "surface" of the element body 20 as referred to herein means a surface that can be observed as a surface when the entire element body 20 is observed. That is, even if there are microscopic unevenness or steps that cannot be recognized unless a part of the element body 20 is observed under magnification with a microscope or the like, the surface is expressed as a flat surface or a curved surface. The six flat surfaces 22 face different directions. The six flat surfaces 22 are broadly classified 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.

[0013] Further, on the outer surface 21 of the element body 20, the boundary between two adjacent flat surfaces 22 and the boundary between three adjacent flat surfaces 22 are curved surfaces. That is, the corners of the element body 20 are subjected to so-called round chamfering.

[0014] As shown in FIG. 2, the dimension of the element body 20 along the first axis X is larger than the dimension along the third axis Z. The material of the element body 20 is dielectric ceramic. Specifically, the material of the element body 20 contains BaTiO3 as a main component. Further, the material of the element body 20 may contain CaTiO3, SrTiO3, CaZrO3 or the like as a main component. The material of the element body 20 may also contain a Mn compound, a Co compound, a Si compound, a rare earth compound, or the like as an accessory component.

[0015] As shown in FIG. 3, the electronic component 10 includes four first internal electrodes 41 and four second internal electrodes 42 as wiring. The first internal electrodes 41 and the second internal electrodes 42 are embedded inside the element body 20.

[0016] The material of the first internal electrode 41 is a conductive material. For example, the material of the first internal electrode 41 is Ni. Further, the material of the first internal electrode 41 may further include a metal such as Ni, Cu, Ag, Au, Pt, Sn, Pd, or an alloy containing any of these metals. The material of the second internal electrode 42 is the same as that of the first internal electrode 41.

[0017] The first internal electrode 41 has a rectangular plate shape. A 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. Similarly to the first internal electrode 41, a main surface of the second internal electrode 42 is perpendicular to the second axis Y.

[0018] A dimension of the first internal electrode 41 along the first axis X is smaller than a dimension of the element body 20 along the first axis X. Further, as shown in Fig. 1, a dimension of the first internal electrode 41 along the third axis Z is approximately two-thirds of the dimension of the element body 20 along the third axis Z. Dimensions of the second internal electrode 42 in each direction are the same as those of the first internal electrode 41.

[0019] As shown in Fig. 3, the first internal electrodes 41 and the second internal electrodes 42 are alternately arranged in the direction along the second axis Y. That is, from the side surface 22C facing the second positive direction Y1 toward the second negative direction Y2, a total of eight internal electrodes are alternately arranged in the order of the first internal electrode 41 and the second internal electrode 42. In this embodiment, distances between adjacent internal electrodes in the direction along the second axis Y are equal to each other.

[0020] As shown in Fig. 1, all four first internal electrodes 41 and four second internal electrodes 42 are 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 offset toward the first positive direction X1, and the second internal electrodes 42 are located offset toward the first negative direction X2.

[0021] Specifically, the first positive X1 end of the first internal electrode 41 approximately coincides with the first positive X1 end of the base body 20. Therefore, the first positive X1 end of the first internal electrode 41 is exposed from the first end face 22A of the base body 20. The first negative X2 end of the first internal electrode 41 is located inside the base body 20 and does not reach the first negative X2 end of the base body 20. On the other hand, the first negative X2 end of the second internal electrode 42 approximately coincides with the first negative X2 end of the base body 20. Therefore, the first negative X2 end of the second internal electrode 42 is exposed from the second end face 22B of the base body 20. The first positive X1 end of the second internal electrode 42 is located inside the base body 20 and does not reach the first positive X1 end of the base body 20.

[0022] As shown in Figure 3, the electronic component 10 includes a first external electrode 61 and a second external electrode 62. The first external electrode 61 has a first electrode 61A, a second electrode 61B, and a third electrode 61C.

[0023] The first electrode 61A covers a portion of the outer surface 21 of the base body 20. Specifically, the first electrode 61A covers the first end face 22A of the base body 20 and a portion of the first positive direction X1 side of the four side surfaces 22C. The first electrode 61A is also connected to the first internal electrode 41 that is exposed from the first end face 22A. The first electrode 61A is almost entirely made of copper and contains a small amount of glass.

[0024] The second electrode 61B covers the outer surface of the first electrode 61A. In other words, the second electrode 61B is laminated on the first electrode 61A. Details of the second electrode 61B will be described later. The third electrode 61C also covers the outer surface of the second electrode 61B. In other words, the third electrode 61C is laminated on the second electrode 61B. A portion of the third electrode 61C protrudes from the second electrode 61B. Although not shown in the diagram, the third electrode 61C has a two-layer structure consisting of a nickel layer and a tin layer, starting from the second electrode 61B side.

[0025] 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 base body 20. Specifically, the first electrode 62A covers the second end face 22B of the base body 20 and a portion of the first negative direction X2 side of the four side surfaces 22C. The first electrode 62A is also connected to the second internal electrode 42 which is exposed from the second end face 22B. The material of the first electrode 62A is the same as the material of the first electrode 62A in the first external electrode 61.

[0026] As shown in Figure 3, the second electrode 62B covers the outer surface of the first electrode 62A. Therefore, the second electrode 62B is laminated on the first electrode 62A. Details of the second electrode 62B will be described later. Also, as shown in Figures 3 and 4, the third electrode 62C covers the outer surface 610 of the second electrode 62B. Therefore, the third electrode 62C is laminated on the second electrode 62B. Also, as shown in Figure 3, a part of the third electrode 62C protrudes from the second electrode 62B. Although not shown in the illustration, the third electrode 62C has a two-layer structure consisting of a nickel layer and a tin layer, in that order from the second electrode 62B side.

[0027] The second external electrode 62 does not extend to the first external electrode 61 on the side surface 22C, and is positioned separately from the first external electrode 61 in the direction along the first axis X. Furthermore, on the side surface 22C of the base body 20, the central portion in the direction along the first axis X is not stacked with the first external electrode 61 and the second external electrode 62. In Figures 1 to 3, the first external electrode 61 and the second external electrode 62 are shown by dashed lines.

[0028] <Regarding the configuration of the second electrode> The configuration of the second electrode 61B of the first external electrode 61 will be described in detail below. The configuration of the second electrode 62B of the second external electrode 62 is the same as that of the first external electrode 61.

[0029] The second electrode 61B contains copper and silicon. Furthermore, the second electrode 61B is a sintered body. The weight ratio of copper to silicon in the second electrode 61B is 0.5 or more and 2 or less. As shown in Figure 4, at least a portion of the copper in the second electrode 61B is spherical copper particles 63. The silicon in the second electrode 61B exists as a silicone resin 64. The silicone resin 64 is a polymer consisting of siloxane bonds and Si-C bonds.

[0030] As shown in Figure 4, the second electrode 61B is divided into two equal parts: a first portion 631 located on the inner surface 620 side of the second electrode 61B, and a second portion 632 located on the outer surface 610 side of the second electrode 61B. The inner surface 620 of the second electrode 61B is the interface of the second electrode 61B that is closer to the first electrode 61A. The outer surface 610 of the second electrode 61B is the side of the second electrode 61B that is opposite to the first electrode 61A. The position where the second electrode 61B is divided into two equal parts is the point where the average thickness of the second electrode 61B is divided into two equal parts, as will be described later.

[0031] As shown in Figure 4, the average particle size of the copper particles 63 differs between the first part 631 and the second part 632. Specifically, the average particle size of the copper particles 63 in the first part 631 is smaller than the average particle size of the copper particles 63 in the second part 632. In other words, the particle size of the copper particles 63 located in the first part 631 is generally smaller than that of the copper particles 63 located in the second part 632. Overall, the particle size of the copper particles 63 decreases as you move towards the inner surface 620 within the second electrode 61B.

[0032] The particle size of the copper particles 63 is calculated as follows: First, the outline of the copper particles 63 is obtained by image processing using an electron microscope. The obtained image is analyzed, and the line segment connecting the edges of one copper particle 63 is defined as the major diameter. In addition, the line segment perpendicular to the major diameter and connecting the edges of the copper particles 63 is defined as the minor diameter. The particle size of the copper particles 63 is calculated as the average of the major diameter and the minor diameter.

[0033] As shown in Figure 5, the silicone resin 64, as silicon, is distributed in a network-like structure. Specifically, when the second electrode 61B is viewed in cross-section, the silicone resin 64 is distributed in a network-like structure, filling the spaces between multiple copper particles 63. In addition, a portion of the silicone resin 64 is in the form of lumps. The lumpy silicone resin 64 is formed when a portion of the network-like silicone resin 64 has condensed. In particular, the proportion of lumpy silicone resin 64 is higher in the first portion 631 compared to the second portion 632.

[0034] The proportion of silicone resin 64 in the first part 631 of the second electrode 61B is higher than the proportion of silicone resin 64 in the second part 632 of the second electrode 61B. That is, the proportion of silicon in the first part 631 is higher than the proportion of silicon in the second part 632. The proportion of silicone resin 64 is calculated as follows: First, a cross-section of the second electrode 61B is photographed with an electron microscope. Next, the area occupied by silicone resin 64 within a certain square area of ​​the photographed image is calculated. Then, the area of ​​silicone resin 64 relative to the area of ​​the square is taken as the proportion of silicone resin 64. At this time, a square area is defined so as not to extend beyond the first part 631, and the proportion of silicone resin 64 is calculated. Then, the proportion of silicone resin 64 is calculated at three or more points within the range of the first part 631, and the average value of these is taken as the proportion of silicone resin 64 in the first part 631. The same procedure is followed for the second part 632.

[0035] The thickness of the first electrode 61A is defined as the shortest distance from the surface facing the base material 20 to the outer surface. Similarly, the thickness of the second electrode 61B is defined as the shortest distance from the inner surface 620 to the outer surface 610. The average thickness of the second electrode 61B is smaller than the average thickness of the first electrode 61A.

[0036] The average thickness of each electrode is calculated as follows. First, a cross-section including the outer surface 610 and inner surface 620 of the second electrode 61B is photographed using an electron microscope. Next, the area along the outer surface 610 of the second electrode 61B is identified from the photographed image. Within this area, the cross-sectional area of ​​the second electrode 61B is calculated by image processing for a measurement range of at least 5 μm. Then, the thickness of the second electrode 61B is calculated by dividing the calculated cross-sectional area of ​​the second electrode 61B within the measurement range by the length of the measurement range. In other words, the thickness of the second electrode 61B is the thickness within the measurement range. The thickness of the second electrode 61B is measured at five cross-sections using this method, and the average thickness is calculated.

[0037] Similarly, the thickness of the first electrode 61A is calculated. That is, a cross-section of the first electrode 61A, including the surface on the base body 20 side and the outer surface, is photographed with an electron microscope. Next, the range along the outer surface of the first electrode 61A is identified from the photographed image. Within this range, the cross-sectional area of ​​the first electrode 61A is calculated by image processing for a measurement range of at least 5 μm. Then, the thickness of the first electrode 61A is calculated by dividing the calculated cross-sectional area of ​​the first electrode 61A within the measurement range by the length of the measurement range. In other words, the thickness of the first electrode 61A is the thickness within the measurement range. The thickness of the first electrode 61A is measured at five cross-sections using this method, and the average value of the said thickness is calculated.

[0038] <Manufacturing methods for electronic components> Next, we will describe the manufacturing method of the electronic component 10. As shown in Figure 6, the manufacturing method for the electronic component 10 includes a laminate preparation step S11, an R-chamfering step S12, a conductive coating step S13, a curing step S14, and a plating step S15.

[0039] First, in forming the base body 20, the laminate preparation step S11 prepares the laminate. At this stage, the laminate is in a state before R-chamfering and is in the shape of a rectangular parallelepiped having six planes 22. For example, first, multiple ceramic sheets that will become the base body 20 are prepared. These sheets are in the shape of thin plates. A conductive paste that will become the first internal electrode 41 is laminated onto these sheets. A ceramic sheet that will become the base body 20 is laminated onto the paste. A conductive paste that will become the second internal electrode 42 is laminated onto these sheets. In this way, the ceramic sheets and conductive paste are laminated. Then, the laminated sheets are pressed together in the lamination direction by means of a mold press or the like. After that, the pressed material is cut to a predetermined size to form an unfired laminate. After that, the unfired laminate is fired at a high temperature to prepare the laminate.

[0040] Next, the R-chamfering process S12 is performed. In the R-chamfering process S12, the laminate prepared in the laminate preparation process S11 is chamfered with rounded edges. This process yields a base body 20 with rounded edges.

[0041] Next, the conductive coating process S13 is performed. In the conductive coating process S13, the first conductive paste is applied by immersion to a portion of the first end face 22A and a portion of the second end face 22B of the base body 20. Specifically, the first conductive paste is applied so as to cover the entire area of ​​the first end face 22A and a portion of the four side faces 22C. The first conductive paste is also applied so as to cover the entire area of ​​the second end face 22B and a portion of the four side faces 22C. The first conductive paste contains copper and silicon components.

[0042] Furthermore, in the conductive coating step S13, the second conductive paste is applied to the first conductive paste in two locations. The second conductive paste is a complex ink. The second conductive paste is prepared as follows: First, an amine compound such as 2-ethylhexylamine and an alcohol amine such as 2-amino-2-methylpropanol are mixed. Then, a silicon component such as silicone resin is added at a rate of 10-300 wt% relative to the weight of Cu alone. Then, a metal salt is further added and dissolved to create the second conductive paste. In other words, the second conductive paste contains copper and silicon components. The sintering start temperature of the copper component is 170 degrees Celsius, and the curing start temperature of the silicon component is 250 degrees Celsius.

[0043] Next, the curing process S14 is performed. Specifically, the curing process S14 involves heating the substrate 20 to which the first conductive paste and the second conductive paste have been applied. In this embodiment, the substrate 20 to which the first conductive paste and the second conductive paste have been applied is heated in a nitrogen atmosphere. The temperature is then maintained within the range of 300 to 600 degrees Celsius. This causes the first conductive paste and the second conductive paste to be fired. During the firing of the second conductive paste, the sintering of the copper component contained in the second electrode 61B and the second electrode 62B begins first. At the point when the sintering of the copper component begins, the silicon component is not yet hardened and remains fluid. Therefore, the silicon component fills the gaps between the copper components. After the sintering of the copper component has begun, when the temperature rises further to the hardening start temperature of the silicon component, the hardening of the silicon component contained in the second electrode 61B and the second electrode 62B begins. That is, the hardening start temperature of the silicon component is higher than the sintering start temperature of the copper component. Then, copper particles 63 are produced by the sintering of the copper component. In addition, silicone resin 64 is produced by the hardening of the silicon component. Furthermore, as mentioned above, since the hardening start temperature of the silicon component is higher than the sintering start temperature of the copper component, a mesh-like silicone resin 64 is formed that fills the gaps between the copper particles 63. As a result, the second electrodes 61B and 62B described above are formed.

[0044] Next, the plating process S15 is performed. Electroplating is carried out at the locations where the second electrodes 61B and 62B are located. As a result, the third electrode 61C is formed on the surface of the second electrode 61B. Also, the third electrode 62C is formed on the surface of the second electrode 62B. Although not shown in the diagram, the third electrodes 61C and 62C are electroplated with two types of metals, nickel and tin, to form a two-layer structure. In this way, the electronic component 10 is formed.

[0045] <Operation of this embodiment> The second electrode 61B has a silicone resin 64, and copper particles 63 are dispersed in this silicone resin 64. As a result, the bending strength of the second electrode 61B is relatively small. Therefore, if an external force such as impact or thermal stress is applied to the electronic component 10, deformation and cracks in the second electrode 61B are more likely to occur before those in the base body 20. In other words, the second electrode 61B plays a role in mitigating the effects of the external force by breaking itself.

[0046] <Effects of this embodiment> The effects of this embodiment will now be described. While the effects of the first external electrode 61 will be described as representative, similar effects can be obtained with the second external electrode 62.

[0047] (1) According to the above embodiment, the presence of the second electrode 61B makes it less likely for cracks or the like to occur in the base body 20 when an external force is applied to the electronic component 10. Even if cracks or the like occur in the second electrode 61B, the first internal electrode 41 is connected to the first electrode 61A. Therefore, conductivity between the first external electrode 61 and the first internal electrode 41 is ensured.

[0048] (2) The silicone resin 64 has a higher adhesion force to other components compared to the copper particles 63. In the above embodiment, the proportion of silicone resin 64 in the first portion 631 of the second electrode 61B is higher than the proportion of silicone resin 64 in the second portion 632 of the second electrode 61B. In other words, the silicone resin 64 is likely to be exposed on the inner surface 620 of the second electrode 61B. Therefore, the silicone resin 64 adheres easily to the first electrode 61A, and the second electrode 61B is less likely to peel off from the first electrode 61A. Furthermore, because the second electrode 61B adheres to the first electrode 61A in this way, even if a crack occurs in the second electrode 61B, the crack will not propagate to the interface between the second electrode 61B and the first electrode 61A, and the entire second electrode 61B will not peel off from the first electrode 61A.

[0049] (3) According to the above embodiment, the second electrode 61B contains silicone resin 64. With an electrode containing silicone resin 64 in this way, the strength of the second electrode 61B can be designed to a desirable value by designing the content of silicone resin 64 to an arbitrary value.

[0050] (4) According to the above embodiment, the average thickness of the second electrode 61B is smaller than the average thickness of the first electrode 61A. With this configuration, the overall thickness of the first external electrode 61 can be reduced compared to the case where the average thickness of the second electrode 61B is the same as the average thickness of the first electrode 61A. In other words, the above configuration is particularly useful in small electronic components.

[0051] (5) In the above embodiment, there is a third electrode 61C that covers the second electrode 61B. With this configuration, even if a crack occurs in the second electrode 61B, it is possible to prevent the crack from propagating to the outer surface of the first external electrode 61, i.e., to the outer surface of the third electrode 61C.

[0052] (6) In the above embodiment, the first electrode 61A and the second electrode 61B are formed by an immersion method. Even when the first external electrode 61 is composed of multiple layers, this method can be used to suppress a decrease in mass production efficiency.

[0053] <Example of changes> The above embodiments and the following modifications can be combined and implemented to the extent that they are not technically contradictory. In the case of modifications applicable to both the first external electrode 61 and the second external electrode 62, the modification relating to the first external electrode 61 will be described as representative.

[0054] 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 having a base body 20, a first external electrode 61, and a second external electrode 62, a thermistor, an inductor, etc.

[0055] In the above embodiment, the material of the base body 20 may be a dielectric, a piezoelectric material, a magnetic material such as ferrite, or a composite body of synthetic resin and metal. In the above embodiment, the second conductive paste may be a nanoink. If it is a nanoink, it is prepared as follows: Nanometal powder is dispersed in a solvent containing cellosolves, carbitols, hydrocarbons, and aromatics. Then, various silicone-modified resins, or silicone resins, or sol-gel materials are added at a concentration of 10-300 wt% relative to the weight of Cu alone. The second conductive paste of the nanoink may be prepared in this way, or by a different method.

[0056] • In the above embodiments, the material used when the second conductive paste is a complex ink is not limited to the examples of the above embodiments. For example, the amine compound may be a primary amine, a secondary amine, or a 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 specified as α, β, γ, etc. 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, and sol-gel materials. Furthermore, metal salts consisting of formic acid, acetic acid, oxalic acid, or other organic acids may be used as the metal salt. An example of this type of metal salt is anhydrous copper formate.

[0057] In the above embodiment, the number of first internal electrodes 41 and second internal electrodes 42 is not limited to the example of the above embodiment. The number of first internal electrodes 41 may be less than or more than four. The same applies to the second internal electrodes 42.

[0058] In the above embodiment, the electronic component 10 may include a glass film. In that case, for example, the glass film may be formed to cover a portion of the outer surface 21 of the base body 20. In other words, even if a glass film is present covering the base body 20, 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.

[0059] In the above embodiment, the material of the first electrode 61A is not limited to the examples of the above embodiment. For example, the material of the first electrode 61A may be a metal such as Ni, Ag, or Cu, or it may be a configuration that includes any of these metals.

[0060] In the above embodiment, the second electrode 61B only needs to cover at least a portion of the first electrode 61A. However, it is preferable that the second electrode 61B covers at least the outer surface of the first electrode 61A that faces the substrate 100 when the electronic component 10 is mounted on the substrate 100.

[0061] For example, the mounting structure shown in Figure 7 includes a substrate 100 and an electronic component 10 mounted on the substrate 100. Furthermore, of the outer surface 21 of the base body 20, the side 22C facing the second positive direction Y1 is the mounting surface 22S relative to the substrate 100. The first electrode 61A covers the surface of the outer surface 21 of the base body 20 facing the first positive direction X1, and a portion of the four side surfaces 22C. That is, the first electrode 61A covers a portion of the mounting surface 22S. The second electrode 61B covers a total of four surfaces of the outer surface of the first electrode 61A: the surface facing the second positive direction Y1, the surface facing the second negative direction Y2, the surface facing the third positive direction Z1, and the surface facing the third negative direction Z2. Furthermore, in the example shown in Figure 8, the second electrode 61B covers a total of three surfaces of the outer surface of the first electrode 61A: the surface facing the second positive direction Y1, the surface facing the third positive direction Z1, and the surface facing the third negative direction Z2. In the example shown in Figure 9, the second electrode 61B covers a total of two surfaces of the outer surface of the first electrode 61A: the surface facing the second positive direction Y1 and the surface facing the first positive direction X1. Moreover, in the example shown in Figure 10, the second electrode 61B covers only the surface of the outer surface of the first electrode 61A facing the second positive direction Y1. In other words, in all of the examples shown in Figures 7 to 10, the second electrode 61B covers the outer surface of the outer surface of the first electrode 61A that covers the mounting surface 22S. Furthermore, according to the electronic component 10 in the examples shown in Figures 7 to 10, if the second electrode 61B collides with the substrate 100 during mounting, the effect of (1) in the above embodiment can be exerted to suppress the influence of external force on the base body 20.

[0062] In the above embodiment, the proportion of silicone resin 64 in the first portion 631 of the second electrode 61B may be lower or the same as the proportion of silicone resin 64 in the second portion 632 of the second electrode 61B.

[0063] In the above embodiment, the average thickness of the second electrode 61B may be the same as or less than the average thickness of the first electrode 61A. On the other hand, it is preferable to set the thickness such that the deflection strength of the second electrode 61B is less than that of the first electrode 61A.

[0064] In the above embodiment, the configuration relating to the third electrode 61C in the first external electrode 61 may be omitted. In the above embodiment, the average particle size of the copper particles 63 in the first portion 631 of the second electrode 61B may be the same as, smaller than, or larger than the average particle size of the copper particles 63 in the second portion 632 of the second electrode 61B.

[0065] In the above embodiment, silicon is not limited to silicone resin 64. For example, silicon may be silica (silicon dioxide) or the like. The manufacturing process for the electronic component 10 in the above embodiment is not limited to the example of the above embodiment. For example, the base body 20 may be subjected to treatments such as physical polishing.

[0066] • In the above embodiments, the method for applying the first conductive paste and the second conductive paste is not limited to the examples of the embodiments described above. For example, these pastes may be applied by printing, or by an inkjet printing method, etc. Also, the application methods for the first conductive paste and the second conductive paste may differ.

[0067] In the above embodiment, the curing process S14 may be carried out in multiple stages. That is, the firing may be carried out in multiple stages. In the above embodiment, the sintering start temperature of the copper component and the hardening start temperature of the silicon component of the second conductive paste are not limited to the examples of the above embodiment.

[0068] <Note> The technical concepts that can be derived from the above embodiments and modifications are described below. [1] An electronic component comprising a body, an internal electrode located inside the body, and an external electrode covering a part of the outer surface of the body, wherein the external electrode has a first electrode covering a part of the outer surface of the body and connected to the internal electrode, and a second electrode covering the outer surface of the first electrode, and the second electrode having spherical copper particles and silicon.

[0069] [2] The electronic component according to [1], in which the second electrode is divided into a first portion located on the side of the first electrode and a second portion located on the opposite side of the first electrode, the proportion of silicon in the first portion is higher than the proportion of silicon in the second portion.

[0070] [3] The average thickness of the second electrode is smaller than the average thickness of the first electrode. [1] or [2] The electronic component described above. [4] The electronic component according to any one of [1] to [3], wherein the external electrode has a third electrode covering the outer surface of the second electrode.

[0071] [5] The first electrode is an electronic component according to any one of [1] to [4], comprising copper and glass. [6] A mounting structure for an electronic component comprising a substrate and an electronic component mounted on the substrate, wherein the electronic component comprises a body, an internal electrode located inside the body, and an external electrode covering a part of the outer surface of the body, the external electrode having a first electrode covering a part of the outer surface of the body and connected to the internal electrode, and a second electrode covering the outer surface of the first electrode, the second electrode having spherical copper particles and silicon, and when the outer surface of the body facing the substrate is considered the mounting surface, the first electrode covers at least a part of the mounting surface, and the second electrode covers at least the outer surface of the portion of the outer surface of the first electrode that covers the mounting surface. [Explanation of Symbols]

[0072] 10…Electronic components 20... Base body 41...First internal electrode 61...First external electrode 61A…1st electrode 61B…Second electrode 61C…Third electrode 63…Copper particles 64…Silicone resin 631...Part 1 632…Second part

Claims

1. The base body and, The internal electrode located inside the aforementioned body, An external electrode covering a part of the outer surface of the aforementioned body, Equipped with, The external electrode comprises a first electrode that covers a portion of the outer surface of the base body and is connected to the internal electrode, and a second electrode that covers the outer surface of the first electrode. The second electrode has spherical copper particles and silicon, Within the second electrode, the particle size of the copper particles decreases as you move toward the first electrode. Electronic components.

2. The base body and, The internal electrode located inside the aforementioned body, An external electrode covering a part of the outer surface of the aforementioned body, Equipped with, The external electrode comprises a first electrode that covers a portion of the outer surface of the base body and is connected to the internal electrode, and a second electrode that covers the outer surface of the first electrode. The second electrode has spherical copper particles and silicon, When the second electrode is divided into two equal parts, a first portion located on the side of the first electrode and a second portion located on the opposite side of the first electrode, the proportion of silicon in the first portion is higher than the proportion of silicon in the second portion. Electronic components.

3. The average thickness of the second electrode is smaller than the average thickness of the first electrode. The electronic component according to claim 1.

4. The external electrode has a third electrode that covers the outer surface of the second electrode. The electronic component according to claim 1.

5. The first electrode includes copper and glass. The electronic component according to claim 1.

6. It comprises a substrate and electronic components mounted on the substrate, The aforementioned electronic component is The base body and, The internal electrode located inside the aforementioned body, An external electrode covering a part of the outer surface of the aforementioned body, Equipped with, The external electrode comprises a first electrode that covers a portion of the outer surface of the base body and is connected to the internal electrode, and a second electrode that covers the outer surface of the first electrode. The second electrode has spherical copper particles and silicon, Within the second electrode, the particle size of the copper particles decreases as you move towards the first electrode. When the outer surface of the aforementioned body that faces the substrate is designated as the mounting surface, The first electrode covers at least a portion of the mounting surface, The second electrode covers at least the outer surface of the portion of the outer surface of the first electrode that covers the mounting surface. The mounting structure of electronic components.

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