JP2020113673A - Electronic component - Google Patents

Abstract

To provide an electronic component capable of preventing the removal of an external electrode.SOLUTION: An electronic component 1 comprises: an element body 3 containing ceramic; and an external electrode 5. The external electrode 5 has: a sintered metal layer E1 disposed on the element body 3; an insulative resin layer E2 disposed on the sintered metal layer E1; and a conductive resin layer E3 disposed on the insulative resin layer E2. An outer edge E1a of the sintered metal layer E1 is exposed from the insulative resin layer E2. An outer edge E3a of the conductive resin layer E3 covers the outer edge E1a and comes into contact with the element body 3.SELECTED DRAWING: Figure 2

Description

One form of the present invention relates to an electronic component.

Patent Document 1 discloses a ceramic electronic component including a ceramic body and external electrodes. The external electrode includes a metal electrode layer, an insulating resin layer, and a conductive resin layer. The conductive resin layer absorbs the bending of the external electrode and suppresses the generation of cracks due to thermal shock. The insulating resin layer can reduce the proportion of the expensive conductive resin layer in the external electrode. As a result, the ceramic electronic component can be improved in reliability and economy.

International Publication No. 2014/024593

In the above ceramic electronic component, the insulating resin layer and the conductive resin layer do not reach the surface of the ceramic body, and a part of the metal electrode layer is exposed. Therefore, the metal electrode layer is oxidized and a metal oxide layer is formed between the metal electrode layer and the conductive resin layer. Since the metal oxide layer has low mechanical strength, a crack is likely to occur inside the metal oxide layer or between the metal oxide layer and the conductive resin layer, and the crack is the starting point between the metal electrode layer and the insulating resin layer or the insulating resin layer. Peeling may occur between the layer and the conductive resin layer.

One aspect of the present invention provides an electronic component capable of suppressing peeling of an external electrode.

An electronic component according to one aspect of the present invention includes an element body including ceramics and an external electrode, and the external electrode includes a sintered metal layer disposed on the element body and a sintered metal layer on the sintered metal layer. The insulating resin layer is disposed, and the conductive resin layer is disposed on the insulating resin layer, and the first outer edge portion of the sintered metal layer is exposed from the insulating resin layer. The second outer edge portion of the conductive resin layer covers the first outer edge portion and is in contact with the element body.

In the above one aspect, the conductive resin layer has a second outer edge portion that covers the first outer edge portion of the sintered metal layer exposed from the insulating resin layer and is in contact with the element body. Therefore, the oxidation of the sintered metal layer can be suppressed. Thereby, peeling of the external electrode can be suppressed.

In the above one aspect, the distance between the outer edge of the conductive resin layer and the outer edge of the sintered metal layer may be 50 μm or more. In this case, it is possible to reliably prevent oxygen from entering between the first outer edge portion of the sintered metal layer and the second outer edge portion of the conductive resin layer. Thereby, peeling of the external electrode can be further suppressed.

In the above one aspect, the thickness of the insulating resin layer may be 30% or more and 95% or less of the sum of the thickness of the conductive resin layer and the thickness of the insulating resin layer. The insulating resin layer does not contain a hard metal component. Therefore, the insulating resin layer has a higher effect of alleviating the stress applied to the external electrode than the conductive resin layer. Therefore, by setting the thickness of the insulating resin layer to 30% or more, the effect of relaxing the stress on the external electrode can be enhanced. By setting the thickness of the insulating resin layer to 95% or less, the conductivity of the external electrode can be ensured.

In the above one aspect, the insulating resin layer may include a thermosetting resin, and the glass transition temperature of the thermosetting resin may be 150° C. or higher. In this case, since the heat resistance of the external electrode is improved, the reliability against thermal shock is improved.

In the one aspect, the element body has a pair of main surfaces facing each other, and an end surface adjacent to the pair of main surfaces, the external electrode, at least one of the pair of main surfaces , And may be disposed on the end face. In this case, the stress applied to the external electrodes by the thermal shock can be relieved. As a result, the generation of cracks is suppressed, and thus the peeling of the external electrode is suppressed.

In the above one aspect, the external electrodes may be arranged on each of the pair of main surfaces. In this case, the stress applied to the external electrodes by the thermal shock can be relieved. As a result, the generation of cracks is suppressed, and thus the peeling of the external electrode is suppressed.

In the one aspect, the element body further has a pair of side surfaces facing each other and adjacent to the pair of main surfaces and the end surface, and the external electrode is also disposed on the pair of side surfaces. Good. In this case, the stress applied to the external electrodes by the thermal shock can be further alleviated. As a result, the generation of cracks is further suppressed, so that the peeling of the external electrode is further suppressed.

In the above one aspect, the first outer edge portion and the second outer edge portion may be disposed on at least one of the pair of main surfaces. In this case, oxidation of the sintered metal layer can be suppressed on at least one of the pair of main surfaces. Thereby, peeling of the external electrode can be suppressed.

According to one aspect of the present invention, there is provided an electronic component capable of suppressing the occurrence of peeling in an external electrode.

It is a perspective view which shows the electronic component which concerns on one Embodiment. It is sectional drawing which shows the electronic component of FIG. It is sectional drawing which shows the electronic component of FIG.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In the description, the same elements or elements having the same function will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a perspective view showing an electronic component according to an embodiment. 2 and 3 are sectional views showing the electronic component of FIG. As shown in FIGS. 1 to 3, the electronic component 1 according to the embodiment includes a ceramic-containing element body 3 and a pair of external electrodes 5. The electronic component 1 is, for example, a monolithic ceramic capacitor. The electronic component 1 may be, for example, a piezoelectric element.

The element body 3 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and ridges, and a rectangular parallelepiped shape with rounded corners and ridges. The element body 3 has, as outer surfaces, a pair of main surfaces 3a facing each other, a pair of side surfaces 3c facing each other, and a pair of end surfaces 3e facing each other. Each main surface 3a, each side surface 3c, and each end surface 3e has a rectangular shape. The direction in which the pair of main surfaces 3a are opposed is the first direction D1, the direction in which the pair of side surfaces 3c is opposed is the second direction D2, and the direction in which the pair of end surfaces 3e is opposed is the third direction. The direction is D3.

The first direction D1 is a direction orthogonal to each main surface 3a. The second direction D2 is a direction orthogonal to each side surface 3c. The third direction D3 is a direction orthogonal to each end surface 3e. The first direction D1, the second direction D2, and the third direction D3 intersect (here, are orthogonal to each other). The first direction D1 is the height direction of the element body 3. The second direction D2 is the width direction of the element body 3. The third direction D3 is the length direction of the element body 3. In the present embodiment, the length of the element body 3 (length in the third direction D3) is the height of the element body 3 (length in the first direction D1), and the width of the element body 3 (second). Length in the direction D2). The length of the element body is, for example, 5.7 mm, the height of the element body 3 is, for example, 2.75 mm, and the width of the element body 3 is, for example, 5.0 mm.

The pair of main surfaces 3a extends in the second direction D2 so as to connect the pair of side surfaces 3c. The pair of main surfaces 3a also extends in the third direction D3 so as to connect the pair of end surfaces 3e. The pair of side surfaces 3c extends in the first direction D1 so as to connect the pair of main surfaces 3a. The pair of side surfaces 3c also extends in the third direction D3 so as to connect the pair of end surfaces 3e. The pair of end surfaces 3e extends in the first direction D1 so as to connect the pair of main surfaces 3a. The pair of end faces 3e also extends in the second direction D2 so as to connect the pair of side faces 3c.

Each main surface 3a is adjacent to each of the pair of side surfaces 3c and the pair of end surfaces 3e. Each side surface 3c is adjacent to each of the pair of main surfaces 3a and the pair of end surfaces 3e. Each end surface 3e is adjacent to each of the pair of main surfaces 3a and the pair of side surfaces 3c.

The element body 3 includes a plurality of laminated dielectric layers. The stacking direction of the plurality of dielectric layers coincides with the direction in which the pair of main surfaces 3a face each other, that is, the first direction D1. Each dielectric layer is formed of a ceramic green sheet sintered body containing, for example, a dielectric material (dielectric ceramic such as BaTiO ₃ system, Ba(Ti,Zr)O ₃ system, or (Ba,Ca)TiO ₃ system). It is configured. In the actual element body 3, the respective dielectric layers are integrated so that the boundaries between the respective dielectric layers cannot be visually recognized.

The electronic component 1 is solder-mounted on an electronic device (for example, a circuit board or an electronic component). The electronic component 1 may be mounted with a sintered metal or a conductive adhesive. In the electronic component 1, one main surface 3a is a mounting surface facing the electronic device.

As shown in FIGS. 2 and 3, the electronic component 1 includes a plurality of internal electrodes 7 and 9 as internal conductors. The internal electrodes 7 and 9 are made of a conductive material usually used as internal electrodes of a laminated electric element. A base metal (for example, Ni or Cu) is used as the conductive material. The internal electrodes 7 and 9 are configured as a sintered body of a conductive paste containing the above conductive material. In this embodiment, the internal electrodes 7 and 9 are made of Ni.

The internal electrode 7 and the internal electrode 9 are arranged at different positions (layers) in the stacking direction (that is, the first direction D1). That is, the internal electrodes 7 and the internal electrodes 9 are alternately arranged in the element body 3 so as to face each other with a gap in the stacking direction. The polarities of the internal electrode 7 and the internal electrode 9 are different from each other. One end of each of the internal electrodes 7 and 9 is exposed at one corresponding end face 3e of the pair of end faces 3e.

The pair of external electrodes 5 are arranged on the end face 3e side (end face 3e and its periphery) of the element body 3, that is, at the end portions of the element body 3 in the third direction D3. The pair of external electrodes 5 are separated from each other. Each external electrode 5 is arranged on the electrode portion 5a arranged on each main surface 3a, the electrode portion 5c arranged on each side surface 3c, and the corresponding one end surface 3e of the pair of end surfaces 3e. And an electrode portion 5e which is formed. The external electrodes 5 are formed on five surfaces, that is, a pair of main surfaces 3a, a pair of side surfaces 3c, and one end surface 3e. The electrode portions 5a, 5c, 5e adjacent to each other are physically and electrically connected to each other.

The electrode portion 5e covers all the one end portions exposed to the end faces 3e of the corresponding internal electrodes 7, 9. The internal electrodes 7 and 9 are directly connected to the corresponding electrode portions 5e. The internal electrodes 7 and 9 are electrically connected to the corresponding external electrodes 5.

As shown in FIGS. 2 and 3, the external electrode 5 includes a sintered metal layer E1 arranged on the element body 3, an insulating resin layer E2 arranged on the sintered metal layer E1, Conductive resin layer E3 disposed on insulating resin layer E2, first plating layer E4 disposed on conductive resin layer E3, and second plating disposed on first plating layer E4 And a layer E5. The second plating layer E5 constitutes the outermost layer of the external electrode 5. The external electrode 5 has a five-layer structure.

The sintered metal layer E1 is formed so as to cover five surfaces of the pair of main surfaces 3a, the pair of side surfaces 3c, and one end surface 3e. The outer edge portion E1a (first outer edge portion) of the sintered metal layer E1 is arranged on each of the pair of main surfaces 3a and the pair of side surfaces 3c. The outer edge portion E1a is exposed from the insulating resin layer E2. The outer edge portion E1a is exposed from the insulating resin layer E2 over the entire circumference. That is, when viewed from the first direction D1 and the second direction D2, the outer edge E1b of the sintered metal layer E1 is located inside the element body 3 with respect to the outer edge E2b of the insulating resin layer E2. The sintered metal layer E1 is also a base metal layer for forming the insulating resin layer E2.

The sintered metal layer E1 contains a metal component and a glass component. The metal component is Cu, for example. The metal component may be Ni. Thus, the sintered metal layer E1 contains a base metal. The sintered metal layer E1 is formed by applying a conductive paste to the surface of the element body 3 and baking it to sinter the metal components. As the conductive paste, for example, a mixture of a metal powder such as Cu or Ni with a glass component, an organic binder, and an organic solvent is used.

The insulating resin layer E2 covers the entire sintered metal layer E1 except the outer edge portion E1a. The insulating resin layer E2 is arranged on the five surfaces of the pair of main surfaces 3a, the pair of side surfaces 3c, and one end surface 3e. The insulating resin layer E2 is separated from the element body 3. The insulating resin layer E2 is not in contact with the element body 3.

The insulating resin layer E2 contains, for example, a thermosetting resin. The glass transition temperature (Tg) of the thermosetting resin is, for example, 150° C. or higher. The thermosetting resin is, for example, phenol resin, acrylic resin, silicone resin, epoxy resin, or polyimide resin. The insulating resin layer E2 may include an ultraviolet curable resin, a thermoplastic resin, or the like. The insulating resin layer E2 does not contain a filler. The insulating resin layer E2 is formed by curing the insulating resin applied on the sintered metal layer E1. As the insulating resin, for example, a mixture of thermosetting resin, organic binder, and organic solvent is used.

The conductive resin layer E3 covers the entire insulating resin layer E2, the outer edge portion E1a of the sintered metal layer E1, and a part of the element body 3. The outer edge portion E3a (second outer edge portion) of the conductive resin layer E3 covers the outer edge portion E1a of the sintered metal layer E1 and is in contact with part of the element body 3. Here, a part of the element body 3 is a part of each main surface 3a and each side surface 3c. That is, the outer edge portion E3a is arranged on each main surface 3a and each side surface 3c similarly to the outer edge portion E1a. The outer edge portion E3a covers the entire circumference of the outer edge portion E1a. The outer edge E3b of the conductive resin layer E3 is located inside the element body 3 with respect to the outer edge E1b of the sintered metal layer E1 and the outer edge E2b of the insulating resin layer E2 when viewed from the first direction D1 and the second direction D2. ing.

The conductive resin layer E3 contains a metal component and a resin component. The metal component is, for example, Ag or Cu. The resin component is, for example, a thermosetting resin. The thermosetting resin is, for example, phenol resin, acrylic resin, silicone resin, epoxy resin, or polyimide resin. The resin component may be a resin such as an ultraviolet curable resin or a thermoplastic resin. The resin component may be the same as or different from the resin contained in the insulating resin layer E2.

The conductive resin layer E3 is formed by curing the conductive resin applied to the entire insulating resin layer E2, a part of the pair of main surfaces 3a, and a part of the pair of side surfaces 3c. As the conductive resin, for example, a mixture of conductive particles, a thermosetting resin, an organic binder, and an organic solvent is used. As the conductive particles, for example, Ag powder, Cu powder, or coated particles are used. The coated particles include, for example, resin particles and a metal layer such as Ag or Cu that coats the surfaces of the resin particles.

The first plating layer E4 is formed on the conductive resin layer E3 by a plating method. In the present embodiment, the first plating layer E4 is a Ni plating layer formed on the conductive resin layer E3 by Ni plating. The first plating layer E4 may be a Sn plating layer, a Cu plating layer, or an Au plating layer. In this way, the first plating layer E4 contains Ni, Sn, Cu, or Au.

The second plating layer E5 is formed on the first plating layer E4 by a plating method. In the present embodiment, the second plating layer E5 is a Sn plating layer formed by Sn plating on the first plating layer E4. The second plating layer E5 may be a Cu plating layer, a Pd plating layer or an Au plating layer. Thus, the second plating layer E5 contains Sn, Cu, Pd or Au. The first plating layer E4 and the second plating layer E5 form a plating layer formed on the conductive resin layer E3. That is, in this embodiment, the plating layer formed on the conductive resin layer E3 has a two-layer structure.

Each of the electrode portions 5a, 5c, 5e has a sintered metal layer E1, an insulating resin layer E2, a conductive resin layer E3, a first plating layer E4, and a second plating layer E5. That is, each electrode portion 5a, 5c, 5e has a five-layer structure.

The sintered metal layer E1 included in each of the electrode portions 5a, 5c and 5e is integrally formed. The insulating resin layer E2 included in each of the electrode portions 5a, 5c, 5e is integrally formed. The conductive resin layer E3 included in each of the electrode portions 5a, 5c, 5e is integrally formed. The 1st plating layer E4 which each electrode part 5a, 5c, 5e has is integrally formed. The second plating layer E5 included in each of the electrode portions 5a, 5c, 5e is integrally formed.

The distance L1 between the outer edge E3b of the conductive resin layer E3 and the outer edge E1b of the sintered metal layer E1 is 50 μm or more. The distance L1 is a distance in the third direction D3. The distance L1 can be measured as follows, for example.

First, a cross-sectional view of the external electrode 5 is acquired. For example, a cross-sectional view of the external electrode 5 when the external electrode 5 is cut along a plane orthogonal to the first direction D1 or the second direction D2 is obtained. The distance L1 is measured by performing image analysis on the acquired cross-sectional view. The cross section is, for example, a plane orthogonal to the first direction D1 and equidistant from the pair of main surfaces 3a, or a plane orthogonal to the second direction D2 and equidistant from the pair of side surfaces 3c. It can be a face. The distance L1 can be, for example, the minimum value of a plurality of measurement results in a plurality of cross-sectional views.

The distance L2 between the outer edge E1b of the sintered metal layer E1 and the outer edge E2b of the insulating resin layer E2 is, for example, 20 μm or more and 300 μm or less. The distance L2 is a distance in the third direction D3. The distance L2 can be measured, for example, in the same manner as the distance L1. The distance L2 is the length in the third direction D3 of the outer edge portion E1a of the sintered metal layer E1 exposed from the insulating resin layer E2. When the distance L2 is 20 μm or more, the electrical connection between the sintered metal layer E1 and the conductive resin layer E3 can be ensured. When the distance L2 is 300 μm or less, the effect of suppressing cracks can be improved.

The sum of the thickness t1 of the insulating resin layer E2 and the thickness t2 of the conductive resin layer E3 is, for example, 50 μm or more and 200 μm or less. The thickness t1 and the thickness t2 are measured, for example, by image-analyzing a cross-sectional view of the external electrode 5. The thickness t1 and the thickness t2 can be, for example, the thickness of the insulating resin layer E2 and the thickness of the conductive resin layer E3 on the end face 3e. The thickness t1 and the thickness t2 may be, for example, the thickness of the insulating resin layer E2 and the thickness of the conductive resin layer E3 at the center of the end face 3e.

The thickness t1 of the insulating resin layer E2 is 30% or more and 95% or less of the sum of the thickness t1 of the insulating resin layer E2 and the thickness t2 of the conductive resin layer E3. The thickness t1 is, for example, 15 μm or more and 190 μm or less. The thickness t2 is, for example, 10 μm or more and 140 μm or less.

As described above, in the electronic component 1, the conductive resin layer E3 covers the outer edge portion E1a of the sintered metal layer E1 exposed from the insulating resin layer E2 and is in contact with the element body E3a. have. Therefore, oxidation of the sintered metal layer E1 can be suppressed. Thereby, peeling of the external electrode 5 can be suppressed. If the outer edge portion E1a is exposed from the outer edge portion E3a, not only the outer edge portion E1a but the entire surface of the sintered metal layer E1 may be oxidized. According to the electronic component 1, it is possible to effectively suppress the oxidation of the sintered metal layer E1 in the manufacturing process, particularly when the conductive resin to be the conductive resin layer E3 is applied.

The distance L1 between the outer edge E3b of the conductive resin layer E3 and the outer edge E1b of the sintered metal layer E1 is 50 μm or more. Therefore, it is possible to reliably prevent oxygen from entering between the outer edge portion E1a of the sintered metal layer E1 and the outer edge portion E3a of the conductive resin layer E3. Thereby, peeling of the external electrode 5 can be further suppressed. The distance L1 may be 100 μm or more, or 200 μm or more.

The thickness t1 of the insulating resin layer E2 is 30% or more and 95% or less of the sum of the thickness t2 of the conductive resin layer E3 and the thickness t1 of the insulating resin layer E2. Compared to the conductive resin layer E3 containing a metal component, the insulating resin layer E2 containing no metal component has a higher effect of relaxing the stress applied to the external electrode. Therefore, by setting the thickness t1 of the insulating resin layer E2 to 30% or more, the effect of relaxing the stress on the external electrode 5 can be enhanced. Further, by setting the thickness t1 of the insulating resin layer E2 to 95% or less, the conductivity of the external electrode 5 can be ensured.

The insulating resin layer E2 contains a thermosetting resin, and the glass transition temperature of the thermosetting resin is 150° C. or higher. Therefore, the heat resistance of the external electrode 5 is improved, and the reliability against thermal shock is improved.

The element body 3 has a pair of main surfaces 3a, a pair of side surfaces 3c, and a pair of end surfaces 3e, and each external electrode 5 has a pair of main surfaces 3a, a pair of side surfaces 3c, and a pair of end surfaces 3e. Of the corresponding one of the end faces 3e. Therefore, for example, as compared with the case where the external electrode 5 is formed only on the one main surface 3a, the stress applied from the mounting substrate to the external electrode 5 by the thermal shock can be relaxed. As a result, the generation of cracks is suppressed, and thus the peeling of the external electrode 5 is further suppressed. Further, as a result of relaxing the stress applied to the external electrode 5, the stress applied to the element body 3 through the external electrode 5 is also relaxed. As a result, the occurrence of cracks in the element body 3 is also suppressed.

The present invention is not necessarily limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

Each external electrode 5 may be arranged only on one main surface 3a. That is, the external electrode 5 may have one electrode portion 5a and may not have the other electrode portion 5a, the electrode portion 5e, and the pair of electrode portions 5c.

The pair of external electrodes 5 may be arranged on three surfaces of one main surface 3a and a pair of end surfaces 3e facing each other. That is, each external electrode 5 may be arranged on two surfaces of the one main surface 3a and the corresponding one end surface 3e of the pair of end surfaces 3e. That is, the external electrode 5 may have one electrode portion 5a and the electrode portion 5e, and may not have the other electrode portion 5a and the pair of electrode portions 5c. In this case, as compared with the case where the external electrode 5 is formed only on the one main surface 3a, the stress applied from the mounting substrate to the external electrode 5 due to thermal shock can be relaxed. As a result, the generation of cracks is suppressed, and thus the peeling of the external electrode 5 is suppressed. The length of the electrode portion 5e in the first direction D1 may be shorter than the length of the end face 3e in the first direction D1. That is, the electrode portion 5e may be separated from the other main surface 3a. The length of one of the electrode portions 5a and 5e in the second direction D2 may be shorter than the length of the end surface 3e in the second direction D2. That is, the external electrode 5 may be arranged on a part of the one main surface 3a in the second direction D2 and a part of the end surface 3e in the second direction D2. The length of the electrode portion 5e in the first direction D1 may be shorter than the length of the end face 3e in the first direction D1. That is, the external electrode 5 may be separated from the other main surface 3a.

The pair of external electrodes 5 may be arranged on four surfaces of a pair of main surfaces 3a facing each other and a pair of end surfaces 3e facing each other. That is, each external electrode 5 may be disposed on three surfaces of the pair of main surfaces 3a and the corresponding one end surface 3e of the pair of end surfaces 3e. That is, the external electrode 5 may include the pair of electrode portions 5a and 5e and may not include the pair of electrode portions 5c. Also in this case, as compared with the case where the external electrode 5 is formed only on the one main surface 3a, the stress applied from the mounting substrate to the external electrode 5 due to the thermal shock can be relaxed. As a result, the generation of cracks is suppressed, and thus the peeling of the external electrode 5 is suppressed. The length of the pair of electrode portions 5a and 5e in the second direction D2 may be shorter than the length of the end surface 3e in the second direction D2. That is, the external electrode 5 may be arranged on a part of the pair of main surfaces 3a in the second direction D2 and a part of the end surface 3e in the second direction D2.

The outer edge portion E1a and the outer edge portion E3a may be disposed on at least one of the pair of main surfaces 3a. That is, the entire circumference of the outer edge of the sintered metal layer E1 does not have to be the outer edge E1a. Further, the entire circumference of the outer edge portion of the conductive resin layer E3 may not be the outer edge portion E3a. Even in this case, oxidation of the sintered metal layer E1 can be suppressed on at least one of the pair of main surfaces 3a. Thereby, peeling of the external electrode 5 can be suppressed.

The effects of the electronic component according to the above-described embodiment will be specifically described with reference to examples and comparative examples.

[Influence of distance L1]
The influence of the distance L1 (see FIG. 2) between the outer edge of the conductive resin layer and the outer edge of the sintered metal layer on the peeling of the external electrode was evaluated. Samples 1 to 10 were used for this evaluation.

(Sample 1)
As the electronic component according to the example, the sample 1 corresponding to the electronic component according to the above-described embodiment was prepared. In Sample 1, the outer edge of the conductive resin layer covered the outer edge of the sintered metal layer and was in contact with the element body. Regarding the size (chip size) of Sample 1, the length was 5.7 mm, the width was 5.0 mm, the height was 2.75 mm, and the distance L1 (see FIG. 2) was 10 μm. The thickness t1 (see FIG. 2) of the insulating resin layer is 15 μm, the thickness t2 of the conductive resin layer (see FIG. 2) is 55 μm, the sum of the thickness of the insulating resin layer and the thickness of the conductive resin layer (the entire resin layer). Thickness) was 70 μm. The glass transition temperature (Tg) of the thermosetting resin contained in the insulating resin layer was 120°C.

(Samples 2-8)
Samples 2 to 8 were prepared in the same manner as Sample 1 except that the distance L1 was set to the value shown in Table 1. Also in Samples 2 to 8, the outer edge portion of the conductive resin layer covered the outer edge portion of the sintered metal layer and was in contact with the element body.

(Sample 9)
Sample 9 was prepared as an electronic component according to the comparative example. As shown in Table 1, in Sample 9, the distance L1 was 0 μm. That is, in Sample 9, the outer edge of the conductive resin layer and the outer edge of the sintered metal layer were made to coincide when viewed from the main surface side and the side surface side of the element body. The outer edge portion of the conductive resin layer covers the outer edge portion of the sintered metal layer when viewed from the main surface side and the side surface side of the element body, but is not in contact with the element body.

(Sample 10)
Sample 10 was prepared as an electronic component according to the comparative example. As shown in Table 1, in Sample 10, the distance L1 was set to −100 μm. That is, in Sample 10, the outer edge of the conductive resin layer was located at a position of 100 μm inside the element body as compared with the outer edge of the sintered metal layer when viewed from the main surface side and the side surface side of the element body. The outer edge of the sintered metal layer is exposed from the conductive resin layer.

With respect to Samples 1 to 10 as described above, the thermal shock test was performed in which the environmental temperature was changed to a low temperature (-55°C) and a high temperature (150°C) every 30 minutes, and the number of repetitions until the external electrodes were peeled off was counted ( Temperature cycle test) was performed. The test results of this thermal shock test are shown in Table 1.

As shown in Table 1, the peeling of the external electrode occurred in Sample 9 at 800 times and in Sample 10 at 500 times, whereas in Samples 1 to 8, peeling of the external electrode did not occur until 1200 times or more. In Sample 9, the conductive resin layer covers the sintered metal layer when viewed from the main surface side and the side surface side of the element body, but is not in contact with the element body. Therefore, the outer edge portion of the conductive resin layer covers the outer edge portion of the sintered metal layer, and the sintered metal layer is more easily oxidized than in Samples 1 to 8 in contact with the element body, and peeling of the external electrode occurs. It seems that it was easy. In Sample 10, since the sintered metal layer was exposed, it is considered that the sintered metal layer was more easily oxidized than Sample 9, and the external electrode was likely to be peeled off. Further, according to the comparison of the test results of Samples 1 to 8, it was found that the longer the distance L1 is, the more the number of times until peeling of the external electrode occurs.

[Influence of thickness ratio of insulating resin layer]
The thickness ratio of the insulating resin layer to the sum (thickness of the entire resin layer) of the thickness t2 of the conductive resin layer (see FIG. 2) and the thickness t1 of the insulating resin layer (see FIG. 2) is used for peeling the external electrode. We evaluated the impact. Samples 4, 11 to 17 were used for this evaluation.

(Samples 11 to 15)
Samples 11 to 15 were prepared in the same manner as Sample 4, except that the thickness t1 of the insulating resin layer and the thickness t2 of the conductive resin layer were changed and the thickness ratio of the insulating resin layer was set to the value shown in Table 2. ..

(Samples 16 and 17)
Same as Sample 1 except that the distance L1, the thickness t1 of the insulating resin layer, the thickness t2 of the conductive resin layer, the thickness of the entire resin layer, and the thickness ratio of the insulating resin layer were set to the values shown in Table 2. Samples 16 and 17 were prepared.

With respect to Samples 4 and 11 to 17 as described above, the thermal shock is obtained by changing the environmental temperature to a low temperature (-55°C) and a high temperature (175°C) every 30 minutes and counting the number of repetitions until the external electrode is peeled off. The test was conducted. The test results of this thermal shock test are shown in Table 2.

As shown in Table 2, by comparing the test results of Samples 4 and 11 to 15, it was found that the higher the thickness ratio of the insulating resin layer, the more the number of times until the peeling of the external electrode occurred. .. Further, the comparison of the test results of Samples 16 and 17 also revealed that the higher the thickness ratio of the insulating resin layer is, the more the number of times until peeling of the external electrode occurs. According to the comparison of the test results of Samples 13 and 16, when the insulating resin layer has the same thickness ratio, the longer the distance L1 and the larger the thickness of the entire resin layer, the number of times until peeling of the external electrode occurs. Was found to increase. Further, according to the comparison of the test results of Samples 14 and 17, when the insulating resin layer has the same thickness ratio, the distance L1 is longer and the thickness of the entire resin layer is larger until peeling of the external electrode occurs. It turns out that the number of times increases.

[Evaluation of glass transition temperature]
The effect of the glass transition temperature on the exfoliation of the external electrode was evaluated. Samples 4, 14, and 18 to 22 were used for this evaluation.

(Samples 18 to 20)
Samples 18 to 20 were prepared in the same manner as Sample 4, except that the thermosetting resin having the glass transition temperature (Tg) shown in Table 3 was used for the insulating resin layer.

(Samples 21 and 22)
Samples 21 and 22 were prepared in the same manner as Sample 14 except that the thermosetting resin having the glass transition temperature (Tg) shown in Table 3 was used for the insulating resin layer.
did.

With respect to the samples 4, 14, 18 to 22 as described above, the environmental temperature was changed to a low temperature (-55°C) and a high temperature (175°C) every 30 minutes, and the number of repetitions until the external electrode was peeled off was counted. A thermal shock test was carried out. The test results of this thermal shock test are shown in Table 3.

As shown in Table 3, by comparing the test results of Samples 4 and 18 to 20, it was found that the higher the glass transition temperature, the more the number of times until the peeling of the external electrode occurred. In addition, the comparison of the test results of Samples 14, 21, and 22 also revealed that the higher the glass transition temperature, the more the number of times until the peeling of the external electrode occurs. According to the comparison of the test results of Samples 4 and 14, the comparison of the test results of Samples 19 and 21, and the comparison of the test results of Samples 20 and 22, when the glass transition temperatures are the same, the thickness of the insulating resin layer is It was found that the higher the ratio, the greater the number of times until peeling of the external electrode occurs.

DESCRIPTION OF SYMBOLS 1... Electronic component, 3... Element body, 3a... Main surface, 3c... Side surface, 3e... End surface, 5... External electrode, E1... Sintered metal layer, E1a... Outer edge (first outer edge), E1b... Outer edge, E2... Insulating resin layer, E2b... Outer edge, 7, 9... Internal electrode, E3... Conductive resin layer, E3a... Outer edge (second outer edge), E3b... Outer edge, E4... First plating layer, E5... 2 plating layers.

Claims (8)

An element body including a ceramic and an external electrode,
The external electrode is
A sintered metal layer disposed on the element body,
An insulating resin layer disposed on the sintered metal layer,
A conductive resin layer disposed on the insulating resin layer,
The first outer edge portion of the sintered metal layer is exposed from the insulating resin layer,
An electronic component in which the second outer edge portion of the conductive resin layer covers the first outer edge portion and is in contact with the element body. The electronic component according to claim 1, wherein a distance between an outer edge of the conductive resin layer and an outer edge of the sintered metal layer is 50 μm or more. The electronic component according to claim 1, wherein the thickness of the insulating resin layer is 30% or more and 95% or less of the sum of the thickness of the conductive resin layer and the thickness of the insulating resin layer. The insulating resin layer contains a thermosetting resin,
The electronic component according to claim 1, wherein the thermosetting resin has a glass transition temperature of 150° C. or higher. The element body has a pair of main surfaces facing each other, and an end surface adjacent to the pair of main surfaces,
The electronic component according to claim 1, wherein the external electrode is arranged on at least one of the pair of main surfaces and the end surface. The electronic component according to claim 5, wherein the external electrode is disposed on each of the pair of main surfaces. The element body further has a pair of side surfaces facing each other and adjacent to the pair of main surfaces and the end surface,
The electronic component according to claim 5, wherein the external electrode is also arranged on the pair of side surfaces. The electronic component according to claim 5, wherein the first outer edge portion and the second outer edge portion are arranged on at least one of the pair of main surfaces.

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