Electronic component, electronic component device, and method for manufacturing electronic component

Abstract

An electronic component includes an element body and an external electrode. The external electrode is disposed on the element main body and includes a conductive resin layer and a plating layer formed on the conductive resin layer. The external electrode has a hole formed from the surface of the plating layer and reaching the conductive resin layer.

Description

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Japanese Patent Application No. 2024-168042, filed on September 27, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] One aspect of this disclosure relates to an electronic component. Another aspect of this disclosure relates to an electronic component device. Yet another aspect of this disclosure relates to a method of manufacturing an electronic component. Background Technology

[0004] Known electronic components include a component body and an external electrode disposed on the component body (for example, see Japanese Unexamined Patent Publication No. 2008-166666). The external electrode includes, for example, a conductive resin layer and a plating layer formed on the conductive resin layer. Summary of the Invention

[0005] The conductive resin layer typically comprises multiple conductive particles and resin. This resin tends to absorb moisture. When the electronic component is heated, the absorbed moisture may vaporize, causing volume expansion. In this case, stress may act on the conductive resin layer, potentially leading to cracks. For example, the electronic component is heated during the soldering and mounting of the component into an electronic device. The electronic device may include, for example, a circuit board or other electronic components.

[0006] One aspect of this disclosure is to provide an electronic component that prevents cracking in a conductive resin layer. Another aspect of this disclosure is to provide an electronic component device that prevents cracking in a conductive resin layer. Yet another aspect of this disclosure is to provide a method for manufacturing an electronic component that prevents cracking in a conductive resin layer.

[0007] An electronic component according to one aspect of this disclosure includes a component body and an external electrode disposed on the component body. The external electrode includes a conductive resin layer and a plating layer formed on the conductive resin layer. The external electrode has a hole formed from the surface of the plating layer and extending to the conductive resin layer.

[0008] In one aspect, the hole is formed from the surface of the plating layer and extends to the conductive resin layer. Even when the moisture absorbed by the resin vaporizes during heating of the electronic component, the gas generated from the moisture moves outward from the external electrode through the hole. The hole provides a path for the gas movement. Therefore, stress tends not to act on the conductive resin layer. This prevents cracking in the conductive resin layer.

[0009] In one aspect, the plating may include a base plating and a solder plating disposed on the base plating. The inner diameter of the holes in the solder plating may be larger than the inner diameter of the holes in the base plating.

[0010] When electronic components are soldered and mounted onto electronic devices, the solder plating becomes wetted by molten solder. In this case, the molten solder may fill the holes.

[0011] In a structure where the inner diameter of a hole in the solder plating is larger than the inner diameter of a hole in the base plating, the molten solder tends not to fill the hole even when the solder plating is wetted by molten solder. Therefore, this structure reliably prevents cracking in the conductive resin layer even when electronic components are soldered and mounted to electronic devices.

[0012] In one aspect, the conductive resin layer may include: a first portion including a location with the maximum thickness in the conductive resin layer, and a second portion having a thickness less than that of the first portion. An aperture can reach the first portion.

[0013] Because the first part is thicker than the second part, it can absorb more water than the second part.

[0014] In the structure where the hole reaches the first part, the hole includes a path for the movement of gas from the first part. Gas generated by moisture absorbed by the first part reliably moves out of the external electrode through the hole. Therefore, stress tends not to act on the first part of the conductive resin layer. This structure reliably prevents cracking in the conductive resin layer.

[0015] In one aspect, the component body may include an end face, on which an external electrode may be located. The conductive resin layer may include a first portion located in a central region of the end face and a second portion located in a peripheral region of the end face. A hole may reach the first portion.

[0016] A conductive resin layer is formed, for example, by curing a conductive resin paste. The conductive resin paste includes, for example, a curable resin and an organic solvent. The organic solvent vaporizes. Due to the vaporization of the organic solvent, gas is generated in the conductive resin paste. The gas generated by the vaporization of the organic solvent reaches directly from any location in the conductive resin paste where the organic solvent is present to the surface of the conductive resin paste and escapes from the conductive resin paste. In the conductive resin paste, voids are formed at the aforementioned locations due to the vaporization of the organic solvent; these voids act as gas pathways. The conductive resin layer tends to include these voids.

[0017] The inventors have made a new discovery that when the conductive resin layer is formed from a conductive resin paste, the first portion tends to include more voids than the second portion.

[0018] In the structure where the hole reaches the first part, the hole tends to communicate with the voids present in the first part. Gas generated by moisture absorbed by the first part moves from the voids to the hole. Therefore, the gas generated by moisture tends to move further away from the external electrode. Stress further tends not to act on the conductive resin layer. This structure further prevents cracks from forming in the conductive resin layer.

[0019] In this aspect, the pores can reach into the conductive resin layer.

[0020] In a structure where the pores extend into the conductive resin layer, gas generated by moisture tends to move into the pores. Therefore, stress further tends not to act on the conductive resin layer. Consequently, this structure further prevents cracking in the conductive resin layer.

[0021] Another aspect of this disclosure includes an electronic component device comprising: an electronic component, and an electronic device on which the electronic component is soldered and mounted. The electronic component includes: a component body and an external electrode disposed on the component body, the external electrode comprising a conductive resin layer and a plating layer formed on the conductive resin layer. The external electrode has a hole formed from the surface of the plating layer and extending to the conductive resin layer. The hole is exposed from the solder.

[0022] Another aspect of this disclosure describes a method for manufacturing an electronic component, comprising: preparing a component body having an external electrode, the external electrode including a conductive resin layer and a plating layer formed on the conductive resin layer; and forming a hole in the external electrode extending from the surface of the plating layer to the conductive resin layer.

[0023] In this further aspect, a hole is formed on the external electrode of the prepared component body, extending from the plating surface to the conductive resin layer. As described above, the hole includes a path for the movement of gas generated by moisture. Therefore, in the electronic component obtained through this further aspect, stress tends not to act on the conductive resin layer. Thus, this further aspect provides an electronic component that prevents cracking in the conductive resin layer.

[0024] In yet another aspect, forming a hole may include forming the hole to extend into the conductive resin layer.

[0025] When forming a hole involves extending the hole into the conductive resin layer, in the resulting electronic component, as described above, gases generated by moisture tend to move towards the hole formed on the external electrode. In this case, in the resulting electronic component, stress further tends not to act on the conductive resin layer, further preventing cracks from forming in the conductive resin layer.

[0026] In yet another aspect, forming a hole may include laser irradiation of the coated surface.

[0027] When forming a hole involves laser irradiation of the coated surface, the hole is formed by laser irradiation. Therefore, holes extending from the coated surface to the conductive resin layer can be easily and reliably formed. Attached Figure Description

[0028] Figure 1 This is a perspective view showing a multilayer capacitor according to an embodiment;

[0029] Figure 2 This is a view showing the cross-sectional structure of a multilayer capacitor;

[0030] Figure 3 This is a view showing the cross-sectional structure of a multilayer capacitor;

[0031] Figure 4 This is a top view showing the end face;

[0032] Figure 5 This is a view showing the planar structure of the external electrodes;

[0033] Figure 6 This is a view showing the cross-sectional structure of the external electrode;

[0034] Figure 7 This is a view showing the planar structure of the external electrodes;

[0035] Figure 8 This is a view showing the cross-sectional structure of the external electrode;

[0036] Figure 9 This is a schematic diagram illustrating the manufacturing process of the multilayer capacitor;

[0037] Figure 10 This is a view showing the cross-sectional structure of an electronic component device according to another embodiment; and

[0038] Figure 11 This is a planar view showing the external electrode and solder fillet. Detailed Implementation

[0039] In the following description, with reference to the accompanying drawings, the same reference numerals denote the same parts or similar parts with the same function, and repeated descriptions are omitted.

[0040] Reference Figures 1 to 6 The structure of the multilayer capacitor C1 according to the embodiment is explained. Figure 1 This is a perspective view showing the multilayer capacitor of this embodiment. Figure 2 and Figure 3 This is a view showing the cross-sectional structure of the multilayer capacitor. Figure 4 This is a top view showing the end face. Figure 5 This is a view showing the planar structure of the external electrodes. Figure 6 This is a view showing the cross-sectional structure of the external electrode. Figure 6 In the text, the shading lines representing the cross-sections are omitted.

[0041] Electronic components include, for example, the multilayer capacitor C1.

[0042] like Figure 1 As shown, the multilayer capacitor C1 includes a cuboid-shaped element body 3 and a plurality of external electrodes 5. For example, the multilayer capacitor C1 includes a pair of external electrodes 5. The pair of external electrodes 5 are disposed on the surface of the element body 3. The pair of external electrodes 5 are separated from each other. The cuboid shape includes, for example, a cuboid shape with chamfered corners and edges, or a cuboid shape with rounded corners and edges.

[0043] The main body 3 of the component includes four sides 3a and a pair of opposing end faces 3e. All four sides 3a and the pair of end faces 3e are approximately rectangular. The four sides 3a include a first pair of opposing sides 3a and a second pair of opposing sides 3a. The opposing directions of the first pair of sides 3a include direction D2, and the opposing directions of the second pair of sides 3a include direction D3. The opposing directions of the pair of end faces 3e include direction D1.

[0044] For example, a multilayer capacitor C1 is soldered onto an electronic device. The electronic device may include, for example, a circuit board or other electronic components. In the multilayer capacitor C1, for example, one of the four sides 3a faces the electronic device. This one side of the four sides 3a is configured to form a mounting surface. This one side of the four sides 3a includes a mounting surface.

[0045] Direction D2 includes a direction perpendicular to the first pair of side faces 3a and perpendicular to direction D3. Direction D1 includes a direction parallel to the four side faces 3a and perpendicular to directions D2 and D3. Direction D3 includes a direction perpendicular to the second pair of side faces 3a, and direction D1 includes a direction perpendicular to the end face 3e. For example, the length of the component body 3 in direction D1 is greater than the length of the component body 3 in direction D2 and greater than the length of the component body 3 in direction D3. Direction D1 includes the longitudinal direction of the component body 3. The length of the component body 3 in direction D2 can be equal to the length of the component body 3 in direction D3. The length of the component body 3 in direction D2 can be different from the length of the component body 3 in direction D3.

[0046] The length of component body 3 in direction D2 is defined, for example, as the height of component body 3. The length of component body 3 in direction D3 is defined, for example, as the width of component body 3. The length of component body 3 in direction D1 is defined, for example, as the longitudinal length of component body 3. For example, the height of component body 3 ranges from 0.1 to 3.2 mm, the width ranges from 0.1 to 6.3 mm, and the longitudinal length ranges from 0.2 to 7.5 mm. For example, the height of component body 3 is 1.25 mm, the width of component body 3 is 1.25 mm, and the longitudinal length of component body 3 is 2.0 mm.

[0047] The first pair of side faces 3a extends along direction D3 to connect the second pair of side faces 3a to each other. The first pair of side faces 3a extends along direction D1. The second pair of side faces 3a extends along direction D2 to connect the first pair of side faces 3a to each other. The second pair of side faces 3a extends along direction D1. A pair of end faces 3e extends along direction D2 to connect the first pair of side faces 3a to each other. A pair of end faces 3e extends along direction D3 to connect the second pair of side faces 3a to each other.

[0048] The component body 3 includes: a ridge disposed between an end face 3e and a side face 3a, and a ridge disposed between one of the first pair of side faces 3a and one of the second pair of side faces 3a. For example, the ridge is rounded in a curved manner. For example, a so-called rounded corner chamfering treatment is applied to the component body 3. The end face 3e and the side face 3a are indirectly adjacent to each other through the ridge between the end face 3e and the side face 3a. One of the first pair of side faces 3a and one of the second pair of side faces 3a are indirectly adjacent to each other through the ridge between the first pair of side faces 3a and one of the second pair of side faces 3a.

[0049] The component body 3 is constructed by stacking multiple dielectric layers in direction D2. The component body 3 comprises multiple stacked dielectric layers. In the component body 3, the stacking direction of the multiple dielectric layers is consistent with direction D2. Each dielectric layer includes, for example, a sintered body of a ceramic green sheet containing a dielectric material. Examples of dielectric materials include dielectric ceramics. Examples of dielectric ceramics include BaTiO3-based, Ba(Ti,Zr)O3-based, or (Ba,Ca)TiO3-based materials. In the actual component body 3, the dielectric layers are integrated with each other to the point that the boundaries between the dielectric layers are indistinguishable.

[0050] like Figure 2 As shown, the multilayer capacitor C1 includes a plurality of internal electrodes 7. Each internal electrode 7 includes an internal conductor disposed within the component body 3. Each internal electrode 7 is made of a conductive material commonly used as an internal conductor in multilayer electronic components. The conductive material includes, for example, base metals. The conductive material includes, for example, nickel (Ni) or copper (Cu). Each internal electrode 7 is configured as a sintered body comprising a conductive paste including the aforementioned conductive material. For example, the internal electrode 7 includes nickel.

[0051] Multiple internal electrodes 7 are disposed at different positions (layers) in direction D2. The multiple internal electrodes 7 are arranged in the element body 3, spaced apart from each other in direction D2. The internal electrodes 7 adjacent to each other in direction D2 have different polarities. One end of each internal electrode 7 is exposed on a corresponding end face 3e of a pair of end faces 3e. Each internal electrode 7 includes an end exposed on the corresponding end face 3e. The multiple internal electrodes 7 include: an internal electrode 7 exposed on one end face 3e of the pair of end faces 3e, and an internal electrode 7 exposed on the other end face 3e of the pair of end faces 3e. The internal electrodes 7 exposed on one end face 3e and the internal electrodes 7 exposed on the other end face 3e are alternately arranged in direction D2. The multiple internal electrodes 7 are arranged in the element body 3 in a manner aligned in direction D2. Each internal electrode 7 is located in a plane substantially parallel to the first pair of side faces 3a. The direction in which the internal electrodes 7 are opposite each other is perpendicular to the direction parallel to the first pair of side faces 3a.

[0052] In a structure in which multiple dielectric layers are stacked along direction D3, multiple internal electrodes 7 are disposed at different positions (layers) along direction D3. In this structure, internal electrodes 7 exposed on one end face 3e and internal electrodes 7 exposed on another end face 3e are alternately disposed along direction D3. Each internal electrode 7 is located in a plane substantially parallel to the second pair of side faces 3a. The internal electrodes 7 are opposite to each other along direction D3.

[0053] like Figure 1 As shown, a pair of external electrodes 5 are disposed at both ends of the component body 3 in the first direction D1. Each external electrode 5 is disposed on a corresponding end face 3e of a pair of end faces 3e. For example, each external electrode 5 is disposed on four side faces 3a and one end face 3e. Each external electrode 5 is disposed on a corresponding end face 3e. Figure 2 and Figure 3 As shown, the external electrode 5 includes multiple electrode portions 5a and 5e. Electrode portion 5a is located on the side surface 3a and on the edge between the side surface 3a and the end surface 3e. Electrode portion 5e is located on the end surface 3e. The external electrode 5 includes electrode portions located on the edge between adjacent side surfaces 3a. Hereinafter, the edge between the side surface 3a and the end surface 3e will be referred to as the first edge, and the edge between adjacent side surfaces 3a will be referred to as the second edge.

[0054] Each external electrode 5 is formed on five surfaces: four sides 3a and one end face 3e, as well as the aforementioned edge. Adjacent electrode portions 5a and 5e are physically connected and electrically connected. Electrode portion 5e completely covers one end of the corresponding internal electrode 7 among the plurality of internal electrodes 7. Electrode portion 5e is directly connected to the corresponding internal electrode 7. External electrodes 5 are electrically connected to their corresponding internal electrodes 7.

[0055] like Figures 2 to 4 As shown, the external electrode 5 includes a first electrode layer E1, a second electrode layer E2, a third electrode layer E3, and a fourth electrode layer E4. The fourth electrode layer E4 constitutes the outermost layer of the external electrode 5. Each electrode portion 5a and 5e includes the first electrode layer E1, the second electrode layer E2, the third electrode layer E3, and the fourth electrode layer E4.

[0056] The first electrode layer E1 of electrode portion 5a is disposed on the first ridge and not on the side surface 3a. The first electrode layer E1 of electrode portion 5a covers the entire first ridge. The first electrode layer E1 of electrode portion 5a does not cover the side surface 3a. The first electrode layer E1 of electrode portion 5a is in contact with the first ridge. The side surface 3a is exposed from the first electrode layer E1. The first electrode layer E1 of electrode portion 5a may be disposed on the side surface 3a. The first electrode layer E1 of electrode portion 5a may cover a portion of the side surface 3a and the entire first ridge. The first electrode layer E1 of electrode portion 5a may contact that portion of the side surface 3a. The portion of the side surface 3a covered by the first electrode layer E1 of electrode portion 5a may be located near the end face 3e.

[0057] The second electrode layer E2 of electrode portion 5a is disposed on the first electrode layer E1 and the side surface 3a. In electrode portion 5a, the second electrode layer E2 covers the entire first electrode layer E1 and a portion of the side surface 3a. The second electrode layer E2 of electrode portion 5a indirectly covers the first ridge, such that the first electrode layer E1 is located between the second electrode layer E2 and the component body 3. In electrode portion 5a, the second electrode layer E2 is in direct contact with the first electrode layer E1. A portion of the area covered by the second electrode layer E2 of electrode portion 5a is located near the end face 3e. The remaining area of ​​the side surface 3a, excluding the portion covered by the second electrode layer E2, is exposed from the second electrode layer E2. In electrode portion 5a, the second electrode layer E2 is in direct contact with the side surface 3a. In electrode portion 5a, the second electrode layer E2 directly covers the side surface 3a. The second electrode layer E2 of electrode portion 5a is located on the side surface 3a and the first ridge.

[0058] The third electrode layer E3 of electrode portion 5a is disposed on the second electrode layer E2. In electrode portion 5a, the third electrode layer E3 covers the second electrode layer E2. In electrode portion 5a, the third electrode layer E3 is in contact with the second electrode layer E2. In electrode portion 5a, the third electrode layer E3 is in direct contact with the second electrode layer E2.

[0059] The fourth electrode layer E4 of electrode portion 5a is disposed on the third electrode layer E3. In electrode portion 5a, the fourth electrode layer E4 covers the third electrode layer E3. In electrode portion 5a, the fourth electrode layer E4 is in contact with the third electrode layer E3. In electrode portion 5a, the fourth electrode layer E4 is in direct contact with the third electrode layer E3.

[0060] In electrode portion 5a, the third electrode layer E3 and the fourth electrode layer E4 do not contact the side surface 3a. In electrode portion 5a, the third electrode layer E3 is disposed outside the second electrode layer E2 with a gap between it and the side surface 3a. In electrode portion 5a, the fourth electrode layer E4 is disposed outside the second electrode layer E2 with a gap between it and the side surface 3a. The fourth electrode layer E4 of electrode portion 5a is disposed outside the third electrode layer E3. The third electrode layer E3 and the fourth electrode layer E4 of electrode portion 5a are located on the side surface 3a.

[0061] For example, in a structure where one of the first pair of side surfaces 3a is arranged to form a mounting surface, the second electrode layer E2 located on the electrode portion 5a of each second pair of side surfaces 3a can cover only a portion of the edge between the end face 3e and each second pair of side surfaces 3a, as well as only a portion of each second pair of side surfaces 3a. This portion of the edge between the end face 3e and each second pair of side surfaces 3a is, for example, located closer to the side surface 3a arranged to form the mounting surface. This portion of each second pair of side surfaces 3a is, for example, located closer to the corner of the side surface 3a arranged to form the mounting surface and the end face 3e.

[0062] The electrode portions 5a located on each of the second pairs of side surfaces 3a may have the following structures: The second electrode layer E2 of the electrode portions 5a located on each of the second pairs of side surfaces 3a indirectly covers a portion of the edge between the end face 3e and each of the second pairs of side surfaces 3a, such that the first electrode layer E1 is located between the second electrode layer E2 and the first edge. The second electrode layer E2 of the electrode portions 5a located on each of the second pairs of side surfaces 3a directly covers a portion of the area of ​​each of the second pairs of side surfaces 3a. The second electrode layer E2 of the electrode portions 5a located on each of the second pairs of side surfaces 3a directly covers a portion of the first electrode layer E1 located on the edge between the end face 3e and each of the second pairs of side surfaces 3a. The electrode portions 5a located on each of the second pairs of side surfaces 3a include: a region where the first electrode layer E1 is exposed from the second electrode layer E2, and a region where the first electrode layer E1 is covered by the second electrode layer E2.

[0063] The first electrode layer E1 of electrode portion 5e is disposed on end face 3e. The first electrode layer E1 of electrode portion 5e covers the entire end face 3e. The first electrode layer E1 of electrode portion 5e is in contact with the entire end face 3e. In electrode portion 5e, the first electrode layer E1 is in direct contact with end face 3e.

[0064] A second electrode layer E2 is disposed on the first electrode layer E1 in electrode portion 5e. In electrode portion 5e, the second electrode layer E2 covers the first electrode layer E1. In electrode portion 5e, the second electrode layer E2 is in direct contact with the first electrode layer E1. In electrode portion 5e, the second electrode layer E2 indirectly covers the end face 3e, such that the first electrode layer E1 is located between the second electrode layer E2 and the end face 3e. The second electrode layer E2 in electrode portion 5e is located on the end face 3e.

[0065] The third electrode layer E3 of electrode portion 5e is disposed on the second electrode layer E2. In electrode portion 5e, the third electrode layer E3 covers the second electrode layer E2. In electrode portion 5e, the third electrode layer E3 is in contact with the second electrode layer E2. In electrode portion 5e, the third electrode layer E3 is in direct contact with the second electrode layer E2. In electrode portion 5e, the third electrode layer E3 is not in direct contact with the first electrode layer E1.

[0066] In electrode portion 5e, the fourth electrode layer E4 is disposed on the third electrode layer E3. In electrode portion 5e, the fourth electrode layer E4 covers the third electrode layer E3. In electrode portion 5e, the fourth electrode layer E4 is in contact with the third electrode layer E3. In electrode portion 5e, the fourth electrode layer E4 is in direct contact with the third electrode layer E3.

[0067] In electrode portion 5e, the third electrode layer E3 and the fourth electrode layer E4 are disposed outside the second electrode layer E2. The fourth electrode layer E4 of electrode portion 5e is disposed outside the third electrode layer E3 of electrode portion 5e. The third electrode layer E3 and the fourth electrode layer E4 of electrode portion 5e are located on end face 3e.

[0068] The second electrode layer E2 of electrode portion 5e may cover only a portion of the end face 3e. This portion of the end face 3e may be located, for example, further to the side 3a. Electrode portion 5c may have the following structure: The second electrode layer E2 of electrode portion 5e indirectly covers this portion of the end face 3e, such that the first electrode layer E1 is located between the second electrode layer E2 and the end face 3e. The second electrode layer E2 of electrode portion 5e directly covers only a portion of the portion of the first electrode layer E1 located on the end face 3e. Electrode portion 5e includes: a region where the first electrode layer E1 is exposed from the second electrode layer E2, and a region where the first electrode layer E1 is covered by the second electrode layer E2.

[0069] The second electrode layer E2 of electrode portion 5e includes the location of maximum thickness E2. max In electrode portion 5e, the second electrode layer E2 is at its maximum thickness position E2. max It has a maximum thickness. The thickness of the second electrode layer E2 in electrode portion 5e increases from the maximum thickness position E2. maxThe thickness gradually decreases towards the end of the electrode portion 5e. Therefore, the second electrode layer E2 of the electrode portion 5e includes a location with maximum thickness E2. max The portion E2a and the portion E2b, which has a thickness less than that of portion E2a. When viewed from direction D1, portion E2a is located inside portion E2b. Portion E2a may include a first portion, and portion E2b may include a second portion. At the maximum thickness position E2... max The thickness of the second electrode layer E2 is 10 μm or more. For example, at the location of maximum thickness E2... max The thickness of the second electrode layer E2 is 70 μm.

[0070] The first electrode layer E1 is formed by sintering a conductive paste applied to the surface of the element body 3. The conductive paste is applied to the end face 3e and the first edge. The first electrode layer E1 is formed to cover the end face 3e and the first edge. The first electrode layer E1 is formed by sintering the metal components (metal particles) included 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 element body 3. For example, the first electrode layer E1 includes a sintered metal layer made of copper. The first electrode layer E1 may also include a sintered metal layer made of nickel. The first electrode layer E1 may include base metals. The conductive paste includes, for example, particles made of copper or nickel, glass components, organic binders, and organic solvents. The first electrode layers E1 included in the electrode portions 5a and 5e are integrally formed with each other.

[0071] The second electrode layer E2 is formed by curing a conductive resin paste applied to the first electrode layer E1. The conductive resin paste is applied to the first electrode layer E1 and a portion of the side surface 3a. The second electrode layer E2 is formed on the first electrode layer E1 and the component body 3. The conductive resin paste includes, for example, multiple conductive particles, resin, and an organic solvent. The resin includes, for example, a thermosetting resin. The thermosetting resin is, for example, phenolic resin, acrylic resin, silicone resin, epoxy resin, or polyimide resin. The second electrode layer E2 is in contact with a portion of the second ridge. The second electrode layers E2 included in the electrode portions 5a and 5e are integrally formed with each other.

[0072] The second electrode layer E2 includes: a portion E2c located on the central region Rc of the end face 3e, and a portion E2o located on the outer peripheral region Ro of the end face 3e. The outer peripheral region Ro is located outside the central region Rc. The portion E2o is located outside the portion E2c. The second electrode layer E2 of the electrode portion 5e includes the portion E2c and the portion E2o. The portion E2c may include a first portion, and the portion E2o may include a second portion.

[0073] The central region Rc and the outer peripheral region Ro of end face 3e are defined, for example, as follows. Figure 4As shown, end face 3e is divided into sixteen regions. The four inner regions of the sixteen regions are defined as the central region Rc, and the twelve outer regions of the sixteen regions are defined as the peripheral region Ro.

[0074] When viewed from direction D1, part E2a may coincide with part E2c, and part E2b may not coincide with part E2o. When viewed from direction D1, part E2a may be greater than or less than part E2c. When viewed from direction D1, part E2b may be greater than or less than part E2o.

[0075] The third electrode layer E3 is formed on the second electrode layer E2 by a plating process. The third electrode layer E3 may, for example, include a nickel plating layer. The nickel plating layer tends to have better resistance to solder erosion compared to the conductive particles included in the second electrode layer E2. The third electrode layer E3 covers the second electrode layer E2.

[0076] A fourth electrode layer E4 is formed on the third electrode layer E3 by a plating process. The third electrode layer E3 includes a substrate plating layer on which the fourth electrode layer E4 is formed. The fourth electrode layer E4 includes, for example, a solder plating layer. The solder plating layer may include a tin (Sn) plating layer. The fourth plating layer E4 may include tin. The fourth electrode layer E4 may include a tin-silver alloy (Sn-Ag) plating layer, a tin-bismuth alloy (Sn-Bi) plating layer, or a tin-copper alloy (Sn-Cu) plating layer. The fourth electrode layer E4 covers the third electrode layer E3.

[0077] The third electrode layer E3 and the fourth electrode layer E4 are included in the plating layer PL formed on the second electrode layer E2. The external electrode 5 includes the plating layer PL, which includes the third electrode layer E3 and the fourth electrode layer E4. The plating layer PL covers the second electrode layer E2. The third electrode layer E3 included in electrode portions 5a and 5e is integrally formed with each other. The fourth electrode layer E4 included in electrode portions 5a and 5e is integrally formed with each other. The plating layer PL may include other plating layers between the second electrode layer E2 and the third electrode layer E3. The plating layer PL may include other plating layers between the third electrode layer E3 and the fourth electrode layer E4.

[0078] like Figure 5 and Figure 6 As shown, each external electrode 5 has a hole 5h. The hole 5h is formed in the electrode portion 5e. The number of holes 5h is, for example, one. The hole 5h is formed from the surface of the plating layer PL and extends to the second electrode layer E2. The hole 5h is formed from the surface of the fourth electrode layer E4. The hole 5h penetrates the plating layer PL. The hole 5h reaches a portion E2a of the second electrode layer E2. The hole 5h reaches a portion E2c of the second electrode layer E2.

[0079] The deepest point of hole 5h is located within the second electrode layer E2. The deepest point of hole 5h is located closer to the component body 3 in direction D1 than the interface between the second electrode layer E2 and the plating layer PL, and closer to the plating layer PL than the interface between the second electrode layer E2 and the first electrode E1. Hole 5h reaches within the second electrode layer E2. Hole 5h reaches within a portion E2a of the second electrode layer E2. Hole 5h reaches within a portion E2c of the second electrode layer E2. Hole 5h does not penetrate the second electrode layer E2. The maximum depth of hole 5h in the second electrode layer E2 is less than the thickness of the second electrode layer E2 at the location where hole 5h is formed. The depth of hole 5h in the second electrode layer E2 is, for example, 1 μm or more.

[0080] The third electrode layer E3 is exposed in hole 5h. The third electrode layer E3 is exposed from the fourth electrode layer E4 in hole 5h and is not covered by the fourth electrode layer E4. The second electrode layer E2 is exposed in hole 5h. The second electrode layer E2 is exposed from the fourth electrode layer E4 in hole 5h and is not covered by the fourth electrode layer E4. The second electrode layer E2 is separated from the fourth electrode layer E4 on the inner surface defining hole 5h. Hole 5h does not reach the first electrode layer E1. Therefore, the first electrode layer E1 is not exposed in hole 5h.

[0081] The inner diameter of the hole 5h in the fourth electrode layer E4 can be larger than the inner diameter of the hole 5h in the third electrode layer E3. In a structure where the inner diameter of the hole 5h in the fourth electrode layer E4 is larger than that in the third electrode layer E3, the hole 5h gradually narrows from its opening on the surface of the plating layer PL towards its deepest point. For example, the inner diameter of the hole 5h in the fourth electrode layer E4 ranges from 1 to 70 μm. For example, the inner diameter of the hole 5h in the third electrode layer E3 ranges from 1 to 30 μm. For example, the ratio of the inner diameter of the hole 5h in the third electrode layer E3 to the inner diameter of the hole 5h in the fourth electrode layer E4 ranges from 1 / 4 to 2 / 3. The inner diameter of the hole 5h in the fourth electrode layer E4 is defined, for example, by the inner diameter of the opening of the hole 5h on the surface of the fourth electrode layer E4. The inner diameter of the hole 5h in the third electrode layer E3 is defined, for example, by the inner diameter of the opening of the hole 5h on the surface of the third electrode layer E3, i.e., at the interface between the fourth electrode layer E4 and the third electrode layer E3.

[0082] The inner diameter of the hole 5h in the second electrode layer E2 is, for example, smaller than the inner diameter of the hole 5h in the third electrode layer E3. For example, the inner diameter of the hole 5h in the second electrode layer E2 ranges from 1 to 30 μm. The inner diameter of the hole 5h in the second electrode layer E2 is defined, for example, by the inner diameter of the opening of the hole 5h on the surface of the second electrode layer E2, that is, at the interface between the third electrode layer E3 and the second electrode layer E2.

[0083] The opening of the hole 5h in the fourth electrode layer E4 is, for example, approximately circular. The opening of the hole 5h in the third electrode layer E3 is, for example, approximately circular. The opening of the hole 5h in the second electrode layer E2 is, for example, approximately circular. The openings of the holes 5h may also have shapes other than circular. The openings of the holes 5h may be approximately polygonal. In a structure where the openings of the holes 5h are not circular, the inner diameter of the holes 5h is defined, for example, as follows: After obtaining the area of ​​the opening of the hole 5h, the equivalent circle diameter of that area is calculated. The calculated equivalent circle diameter defines the inner diameter of the hole 5h. In a structure where the plating layer PL includes other plating layers between the third electrode layer E3 and the fourth electrode layer E4, the inner diameter of the holes 5h in the other plating layers is, for example, larger than the inner diameter of the holes 5h in the third electrode layer E3 and smaller than the inner diameter of the holes 5h in the fourth electrode layer E4.

[0084] like Figure 7 and Figure 8 As shown, each external electrode 5 may have multiple holes 5h. Figure 7 This is a view showing the planar structure of the external electrodes. Figure 8 This is a view showing the cross-sectional structure of the external electrode. Figure 8 In the text, the shading lines representing the cross-sections are omitted.

[0085] In the structure where the external electrode 5 has a plurality of holes 5h, the plurality of holes 5h can be formed in the electrode portion 5e. Each of the plurality of holes 5h is formed from the surface of the plating layer PL and extends to the second electrode layer E2. Each of the plurality of holes 5h can extend to portion E2a. Each of the plurality of holes 5h can extend to portion E2c. The plurality of holes 5h can differ from each other in shape or depth. Although not shown, the plurality of holes 5h may include holes 5h extending to portion E2b in addition to those extending to portion E2a, and holes 5h may include holes 5h extending to portion E2o in addition to those extending to portion E2c.

[0086] Reference Figure 9 This describes the manufacturing process of the multilayer capacitor C1. Figure 9 This is a schematic diagram illustrating the manufacturing process of a multilayer capacitor according to this embodiment.

[0087] The manufacturing process of the multilayer capacitor C1 includes: preparing a component body 3 with external electrodes 5 formed thereon, and forming holes 5h in the external electrodes 5. As described above, the external electrodes 5 formed on the component body 3 include a first electrode layer E1, a second electrode layer E2, and a plating layer PL (i.e., a third electrode layer E3 and a fourth electrode layer E4). The manufacturing process of the component body 3 is well known in the art, and therefore a detailed description is omitted.

[0088] Forming a hole 5h includes forming a hole 5h extending from the surface of the plating layer PL to the second electrode layer E2. The hole 5h is formed outside the external electrode 5. Forming a hole 5h may include forming a hole 5h extending from the surface of the plating layer PL to the second electrode layer E2.

[0089] like Figure 9 As shown, the hole 5h is formed, for example, by laser irradiation. Forming the hole 5h involves laser irradiation of the surface of the external electrode 5, i.e., the surface of the plating layer PL. Laser irradiation is performed by a laser irradiation device LD. The laser irradiation device LD includes a laser source (not shown) and irradiates the surface of the plating layer PL with a laser beam LL from the laser source. The depth and inner diameter of the hole 5h are adjusted, for example, by adjusting the conditions of the laser irradiation. The conditions of the laser irradiation include, for example, the pulse energy of the laser LL or the irradiation time of the laser LL. The hole 5h can also be formed by micro-hole machining.

[0090] In the multilayer capacitor C1, the hole 5h of the external electrode 5 is formed from the surface of the plating layer PL and extends to the second electrode layer E2. Even when the resin in the second electrode layer E2 vaporizes during heating of the multilayer capacitor C1, the gas generated by the moisture moves out of the external electrode 5 through the hole 5h. The hole 5h includes the gas movement path. Therefore, stress tends not to act on the second electrode layer E2. Thus, the multilayer capacitor C1 prevents cracks from forming in the second electrode layer E2.

[0091] In the multilayer capacitor C1, the plating layer PL may include a third electrode layer E3 and a fourth electrode layer E4. The fourth electrode layer E4 may include a solder plating layer. The inner diameter of the hole 5h in the fourth electrode layer E4 may be larger than the inner diameter of the hole 5h in the third electrode layer E3.

[0092] When the multilayer capacitor C1 is soldered and mounted in an electronic device, the fourth electrode layer E4 is wetted with molten solder. In this case, the molten solder may fill the via for 5 hours.

[0093] In a structure where the inner diameter of the hole 5h in the fourth electrode layer E4 is larger than the inner diameter of the hole 5h in the third electrode layer E3, even if the fourth electrode layer E4 is wetted with molten solder, the molten solder tends not to fill the hole 5h. Therefore, even when the multilayer capacitor C1 is soldered and mounted in an electronic device, the multilayer capacitor C1 with this structure reliably prevents cracks from forming in the second electrode layer E2.

[0094] In the multilayer capacitor C1, the second electrode layer E2 may include: a portion at the maximum thickness location E2 of the second electrode layer E2. max Part E2a and part E2b with a thickness less than part E2a. Hole 5h can reach part E2a.

[0095] Part of E2a has a greater thickness than part of E2b. Therefore, part of E2a can absorb more water than part of E2b.

[0096] In the structure where the hole 5h reaches portion E2a, the hole 5h includes a path for the gas to move from portion E2a. Gas generated from moisture absorbed by portion E2a reliably moves outward from the external electrode 5 through the hole 5h. Therefore, stress tends not to act on portion E2a of the second electrode layer E2. The multilayer capacitor C1 with this structure reliably prevents cracking in the second electrode layer E2.

[0097] In the multilayer capacitor C1, the element body 3 may include an end face 3e, and the external electrode 5 may be located on the end face 3e. The second electrode layer E2 may include a portion E2c located on the central region Rc of the end face 3e, and a portion E2o located on the outer peripheral region Ro of the end face 3e. The hole 5h can reach the portion E2c.

[0098] The second electrode layer E2 is formed, for example, by curing a conductive resin paste. The conductive resin paste includes, for example, a curable resin and an organic solvent. The organic solvent vaporizes. Due to the vaporization of the organic solvent, gas is generated in the conductive resin paste. The gas generated by the vaporization of the organic solvent directly reaches the surface of the conductive resin paste from any location in the conductive resin paste where the organic solvent is present, and escapes from the conductive resin paste. In the conductive resin paste, voids are formed at the aforementioned locations due to the vaporization of the organic solvent; these voids act as gas pathways. The second electrode layer E2 tends to include these voids.

[0099] The inventors have made a new discovery that when the second electrode layer E2 is formed from a conductive resin paste, the portion of E2c tends to include more voids than the portion of E2o.

[0100] In the structure where the hole 5h reaches part E2c, the hole 5h tends to communicate with the voids present in part E2c. Gas generated by moisture absorbed by part E2c moves from the voids to the hole 5h. Therefore, the gas generated by moisture tends to move further away from the outer electrode 5. Stress further tends not to act on the second electrode layer E2. The multilayer capacitor C1 with this structure further prevents cracks from forming in the second electrode layer E2.

[0101] In the multilayer capacitor C1, the hole 5h can reach into the second electrode layer E2.

[0102] In the structure where the hole 5h reaches the second electrode layer E2, the gas generated by moisture tends to move towards the hole 5h. Therefore, stress further tends not to act on the second electrode layer E2. Thus, this structure further prevents cracks from forming in the second electrode layer E2.

[0103] During the manufacturing process of the multilayer capacitor C1, a hole 5h is formed on the outer electrode 5 of the prepared element body 3, extending from the surface of the plating layer PL to the second electrode layer E2. As described above, the hole 5h includes a path for the movement of gas generated by moisture absorbed by the resin in the second electrode layer E2. Therefore, in the multilayer capacitor C1, stress tends not to act on the second electrode layer E2. Thus, the above manufacturing process yields a multilayer capacitor C1 capable of preventing cracks from forming in the second electrode layer E2.

[0104] In the above manufacturing process, forming the hole 5h may include forming the hole 5h to reach into the second electrode layer E2.

[0105] When forming the hole 5h involves forming the hole 5h to reach within the second electrode layer E2, in the obtained multilayer capacitor C1, as described above, the gas generated by moisture tends to move towards the hole 5h. In this case, in the obtained multilayer capacitor C1, stress further tends not to act on the second electrode layer E2, further preventing cracks from forming in the second electrode layer E2.

[0106] In the above manufacturing process, forming a hole 5h may include laser irradiation of the PL coating surface.

[0107] When forming the hole 5h involves laser irradiation of the surface of the plating layer PL, the hole 5h is formed by laser irradiation. Therefore, the hole 5h extending from the surface of the plating layer PL to the second electrode layer E2 can be formed easily and reliably.

[0108] Reference Figures 10 to 11 This describes the structure of an electronic component device (ECD) according to another embodiment. Figure 10 This is a view showing the cross-sectional structure of an electronic component device according to another embodiment. Figure 11 This is a planar view showing the external electrode and solder joints.

[0109] The electronic component device ECD includes a multilayer capacitor C1 and an electronic device ED. The electronic device ED includes, for example, a circuit board or electronic components. The multilayer capacitor C1 is soldered and mounted to the electronic device ED. The electronic device ED includes a main surface EDA and a pair of pad electrodes PE. Each pad electrode PE is disposed on the main surface EDA. The pair of pad electrodes PE are separated from each other. The multilayer capacitor C1 is disposed on the electronic device ED such that one of its side surfaces 3a is opposite to the main surface EDA.

[0110] During the soldering and mounting of the multilayer capacitor C1, molten solder wets the outer electrodes 5 (fourth electrode layer E4). The solidified solder forms solder feet SF on each outer electrode 5. Corresponding outer electrodes 5 are interconnected with the pad electrodes PE via solder feet SF.

[0111] Hole 5h is exposed from solder lead SF. Hole 5h is exposed from cured solder. Cured solder tends not to fill hole 5h. Cured solder tends not to impede the movement of gas generated by moisture beyond the external electrode 5. In the electronic component device ECD, the multilayer capacitor C1 prevents cracks from forming in the second electrode layer E2.

[0112] It should be understood that not all aspects, advantages, and features described herein must be implemented or included by any particular embodiment. In fact, various embodiments are described and illustrated herein, but it will be apparent that other embodiments may be modified in structure and detail.

[0113] The inner diameter of the hole 5h in the fourth electrode layer E4 may not be greater than the inner diameter of the hole 5h in the third electrode layer E3. In a structure where the inner diameter of the hole 5h in the fourth electrode layer E4 is greater than the inner diameter of the hole 5h in the third electrode layer E3, as described above, this structure reliably prevents cracks from forming in the second electrode layer E2.

[0114] In this embodiment and its variations, the electronic component includes a multilayer capacitor. However, applicable electronic components are not limited to multilayer capacitors. Applicable electronic components include, for example, multilayer inductors, multilayer varistors, multilayer piezoelectric actuators, multilayer thermistors, multilayer solid-state battery components, multilayer composite components, and other multilayer electronic components, or other electronic components other than multilayer electronic components.

Claims

1. An electronic component comprising: Component body; as well as An external electrode is disposed on the component body and includes a conductive resin layer and a plating layer formed on the conductive resin layer, wherein... The external electrode has a hole that forms from the surface of the coating and extends to the conductive resin layer.

2. The electronic component according to claim 1, wherein, The coating includes: a base coating and a solder coating disposed on the base coating. The inner diameter of the hole in the solder plating is larger than the inner diameter of the hole in the substrate plating.

3. The electronic component according to claim 1 or 2, wherein, The conductive resin layer includes: a first portion comprising the location of the maximum thickness in the conductive resin layer, and a second portion having a thickness less than that of the first portion. The hole reaches the first part.

4. The electronic component according to claim 1 or 2, wherein, The main body of the component includes an end face. The external electrode is located on the end face. The conductive resin layer includes: a first portion located in the central region of the end face, and a second portion located in the outer peripheral region of the end face. The hole reaches the first part.

5. The electronic component according to any one of claims 1 to 4, wherein, The hole extends into the conductive resin layer.

6. An electronic component device comprising: The electronic component according to any one of claims 1 to 5; as well as An electronic device on which the aforementioned electronic components are welded and mounted, wherein, The hole is exposed from the solder.

7. A method for manufacturing an electronic component, the method comprising: A component body with an external electrode is prepared to be formed, the external electrode comprising a conductive resin layer and a plating layer formed on the conductive resin layer; as well as A hole is formed on the external electrode, the hole extending from the surface of the coating to the conductive resin layer.

8. The method for manufacturing an electronic component according to claim 7, wherein, Forming the hole includes: forming the hole to extend into the conductive resin layer.

9. The method of manufacturing an electronic component according to claim 7 or 8, wherein, Forming the hole includes: irradiating the surface of the coating with a laser.

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