JP2018041904A - Electronic component device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component device in which decrease in bonding strength, via the juncture of an external electrode and a metal terminal, is suppressed.SOLUTION: An electronic component device ED1 includes an electronic component (multilayer capacitor 1) having an elementary body 3 and an external electrode 5 arranged therein, a metal terminal 20 to be connected electrically with the external electrode 5, and a juncture 30 for bonding and electrically connecting the external electrode 5 and metal terminal 20. Outermost layer of the external electrode 5 is a layer containing a precious metal. Outermost layer of the metal terminal 20 is a layer containing a precious metal. The juncture 30 contains a precious metal as main component.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic component device including an electronic component and a metal terminal.

  An electronic component including an element body and an external electrode disposed on the element body, a metal terminal electrically connected to the external electrode, and the external electrode and the metal terminal are joined and electrically connected. An electronic component device including a joint is known (for example, see Patent Document 1).

JP 2002-056763 A

  An object of one aspect of the present invention is to provide an electronic component device in which a decrease in bonding strength through a bonding portion between an external electrode and a metal terminal is suppressed.

  The present inventors conducted a research study on an electronic component device in which a decrease in bonding strength via a bonding portion between an external electrode and a metal terminal is suppressed. As a result, the present inventors have found the following facts and arrived at the present invention.

  When the joining portion is formed of solder, a plating layer made of Sn is employed as the outermost layers of the external electrode and the metal terminal in consideration of compatibility with the solder. In this case, it has been found that, in continuous use in a high temperature environment (for example, an environment exceeding 150 ° C.), the bonding strength through the bonding portion between the external electrode and the metal terminal is lowered.

  The plating layer made of Sn is usually formed on the plating layer made of Ni. The plating layer made of Ni is formed on the base metal layer. The plating layer made of Ni prevents the base metal layer from being eroded by solder. The base metal layer is made of a sintered metal layer such as Cu, for example. In these structures, Ni and Sn are alloyed by heat when the external electrode and the metal terminal are joined by the solder, the thickness of the plating layer made of Ni is reduced, and a part of the base metal layer is applied to the solder. There is a risk of exposure.

  When a part of the base metal layer is exposed to the solder, when the electronic component device is continuously used in a high temperature environment, the metal constituting the base metal layer (for example, Cu described above) is bonded. In some cases, a plating layer made of Ni of a metal terminal is passed through the portion, and a compound is formed with Ni. When a compound is formed by the metal constituting the base metal layer and Ni, voids are formed in the plated layer made of Ni of the metal terminal, and the plated layer made of Ni is easily peeled off from the metal terminal, and the external electrode The joint strength through the joint between the metal terminal and the metal terminal is lowered.

  And the present inventors conducted further research and found the following facts. That is, each outermost layer of the external electrode and the metal terminal contains a noble metal, and the joining portion contains the noble metal as a main component, so that the joining strength through the joining portion between the external electrode and the metal terminal is increased. Reduction is suppressed. The noble metal is a metal that is relatively less likely to cause an alloy reaction and is more stable than Cu or the like from the viewpoint of alloying. The noble metal is, for example, Ag, Au, Pt, Pd or the like.

  An electronic component device according to one aspect of the present invention includes an electronic component including an element body and an external electrode disposed on the element body, a metal terminal electrically connected to the external electrode, and the external electrode And a joint part that joins and electrically connects the metal terminal, and the outermost layer of the external electrode is a layer containing a noble metal, and the outermost layer of the metal terminal is a layer containing a noble metal, The joint contains a precious metal as a main component.

  In the electronic component device according to one aspect of the present invention, the joint portion contains a noble metal as a main component, and each outermost layer of the external electrode and the metal terminal contains a noble metal. Thereby, in the electronic component device according to this aspect, a decrease in bonding strength via the bonding portion between the external electrode and the metal terminal is suppressed.

  According to the one aspect of the present invention, it is possible to provide an electronic component device in which a decrease in bonding strength via a bonding portion between an external electrode and a metal terminal is suppressed.

It is a perspective view which shows the electronic component apparatus which concerns on one Embodiment. It is a figure for demonstrating the cross-sectional structure of the electronic component apparatus which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

  With reference to FIG.1 and FIG.2, the structure of electronic component apparatus ED1 which concerns on this embodiment is demonstrated. FIG. 1 is a perspective view showing an electronic component device according to this embodiment. FIG. 2 is a view for explaining a cross-sectional configuration of the electronic component device according to the present embodiment.

  As shown in FIGS. 1 and 2, the electronic component device ED <b> 1 includes the multilayer capacitor 1, a pair of metal terminals 20, and a joint portion 30. The electronic component device ED1 includes a multilayer capacitor 1 as an electronic component.

  The multilayer capacitor 1 includes an element body 3 having a rectangular parallelepiped shape and a pair of external electrodes 5 disposed on the outer surface of the element body 3. The pair of external electrodes 5 are separated from each other. The rectangular parallelepiped shape includes a rectangular parallelepiped shape in which corners and ridges are chamfered, and a rectangular parallelepiped shape in which corners and ridges are rounded.

  The element body 3 includes, as outer surfaces, a pair of end faces 3a facing each other, a pair of rectangular side faces 3b facing each other, and a pair of rectangular side faces 3c facing each other. Have. The direction in which the pair of end surfaces 3a are facing is the first direction D1, the direction in which the pair of side surfaces 3b is facing is the second direction D2, and the direction in which the pair of side surfaces 3c is facing is the third direction. D3. The first direction D1 is orthogonal to the second direction D2. The third direction D3 is orthogonal to the first direction D1 and the second direction D2. The first direction D1 is the longitudinal direction of the element body 3.

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

The element body 3 is configured by laminating a plurality of dielectric layers in a direction (second direction D2) in which the pair of side surfaces 3b face each other. In the element body 3, the stacking direction of the plurality of dielectric layers coincides with the second direction D2. Each dielectric layer is made of a sintered body of a ceramic green sheet containing a dielectric material (dielectric ceramic such as BaTiO ₃ series, Ba (Ti, Zr) O ₃ series, or (Ba, Ca) TiO ₃ series), for example. It is configured. In the actual element body 3, the dielectric layers are integrated so that the boundary between the dielectric layers is not visible. In the element body 3, the stacking direction of the plurality of dielectric layers may coincide with the third direction D3.

  As shown in FIG. 2, the multilayer capacitor 1 includes a plurality of internal electrodes 7 and 9. The internal electrodes 7 and 9 are made of a conductive material that is normally used as an internal electrode of a laminated electric element. As the conductive material, a base metal (for example, Ni or Cu) is used. The internal electrodes 7 and 9 are configured as a sintered body of a conductive paste containing the conductive material. In the present 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 second direction D2. 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 second direction D2. The internal electrode 7 and the internal electrode 9 have different polarities. When the stacking direction of the plurality of dielectric layers is the third direction D3, the internal electrode 7 and the internal electrode 9 are arranged at different positions (layers) in the third direction D3.

  The external electrodes 5 are disposed on the end face 3 a side of the element body 3, that is, at the end of the element body 3. The external electrode 5 has an electrode portion disposed on the end surface 3a, an electrode portion disposed on the pair of side surfaces 3b, and an electrode portion disposed on the pair of side surfaces 3c. That is, the external electrode 5 is formed on five surfaces, that is, one end surface 3a, a pair of side surfaces 3b, and a pair of side surfaces 3c. The electrode portions adjacent to each other are connected at the ridge portion of the element body 3 and are electrically connected.

  The electrode portion disposed on the end surface 3a is disposed so as to cover all the portions exposed to the end surface 3a of the corresponding internal electrodes 7, 9, and the internal electrodes 7, 9 are electrodes disposed on the end surface 3a. Connected directly to the part. Thereby, the internal electrodes 7 and 9 are electrically connected to the corresponding external electrodes 5.

  As shown in FIG. 2, the external electrode 5 includes a first electrode layer 11 and a second electrode layer 13. That is, each electrode portion of the external electrode 5 includes the first electrode layer 11 and the second electrode layer 13. The second electrode layer 13 constitutes the outermost layer of the external electrode 5.

  The first electrode layer 11 is formed by applying and baking a conductive paste on the surface of the element body 3. The first electrode layer 11 is a sintered metal layer formed by sintering a metal component (metal powder) contained in the conductive paste. That is, the first electrode layer 11 is a sintered metal layer formed on the element body 3. In the present embodiment, the first electrode layer 11 is a sintered metal layer made of Cu. The first electrode layer 11 may be a sintered metal layer made of Ni. Thus, the first electrode layer 11 contains Cu or Ni. As the conductive paste, a powder made of Cu or Ni mixed with a glass component, an organic binder, and an organic solvent is used.

  The second electrode layer 13 is formed by applying a conductive paste for forming the second electrode layer 13 to the surface of the conductive paste for forming the first electrode layer 11 and baking them simultaneously. Yes. The second electrode layer 13 is also a sintered metal layer formed by sintering a metal component (metal powder) contained in the conductive paste. That is, the second electrode layer 13 is a sintered metal layer formed on the element body 3 simultaneously with the first electrode layer 11.

  In the present embodiment, the second electrode layer 13 is a sintered metal layer made of an AgPdCu alloy. Therefore, the second electrode layer 13 contains a noble metal. In the present embodiment, the second electrode layer 13 contains Ag. The second electrode layer 13 contains Pd. The second electrode layer 13 may contain a noble metal other than Ag or Pd.

  In the present embodiment, the conductive paste for forming the second electrode layer 13 is a powder made of AgPdCu alloy mixed with a glass component, an organic binder, and an organic solvent.

  The metal terminal 20 is disposed so as to face the end surface 3a of the multilayer capacitor 1 (element body 3). The metal terminal 20 is electrically connected to the external electrode 5. The metal terminal 20 is electrically connected to the corresponding internal electrodes 7 and 9 through the external electrode 5.

  The metal terminal 20 includes a connection portion 21 and a leg portion 23. The connection part 21 is located facing the end surface 3a. An electrode portion disposed on the end face 3 a of the external electrode 5 is electrically connected to the connection portion 21. The connecting portion 21 extends in the second direction D2, and has a rectangular shape when viewed from the first direction D1.

  The leg portion 23 extends from one end of the connection portion 21. The leg part 23 has the 1st part 23a and the 2nd part 23b. The first portion 23a extends from one end of the connection portion 21 in the second direction D2. That is, the first portion 23a extends in the same direction (second direction D2) as the connection portion 21, and the connection portion 21 and the first portion 23a are located on the same plane.

  The second portion 23b extends in the first direction D1 from one end of the first portion 23a, and has a rectangular shape when viewed from the second direction D2. The first portion 23a and the second portion 23b extend in directions that intersect each other (in the present embodiment, directions that are orthogonal to each other). The second portion 23b is connected to another electronic device (for example, a circuit board or an electronic component).

  The first portion 23a connects the connecting portion 21 and the second portion 23b. That is, the first portion 23a extends in the second direction D2 so as to connect between one end of the connection portion 21 and one end of the second portion 23b. The connection portion 21 and the second portion 23b are positioned so as to be separated from the length of the first portion 23a when viewed in the second direction D2. The connecting portion 21 and the leg portion 23 (the first portion 23a and the second portion 23b) are integrally formed.

  The metal terminal 20 has the base material 25 and the metal layer 27, respectively, as FIG. 2 shows. That is, the connection part 21 and the leg part 23 of the metal terminal 20 include the base material 25 and the metal layer 27. The metal layer 27 constitutes the outermost layer of the metal terminal 20.

  The base material 25 is made of a metal material. In this embodiment, the base material 25 consists of a Fe-Ni alloy.

  The metal layer 27 is formed on the base material 25 by a plating method. The metal layer 27 is a plating layer (plating layer made of Ag) formed on the base material 25 by Ag plating. Therefore, the metal layer 27 contains a noble metal. In the present embodiment, the metal layer 27 contains Ag. The metal layer 27 may contain a noble metal other than Ag.

  The joint portion 30 joins the external electrode 5 and the metal terminal 20. In the present embodiment, the second electrode layer 13 included in the electrode portion disposed on the end surface 3 a of the external electrode 5 and the connection portion 21 of the metal terminal 20 are joined by the joint portion 30. The joint portion 30 has conductivity, and the external electrode 5 and the metal terminal 20 are electrically connected through the joint portion 30.

  The joint portion 30 is formed of a conductive adhesive whose conductive filler is made of Ag. Therefore, the joining part 30 contains a noble metal as a main component. In the present embodiment, the joint portion 30 contains Ag as a main component. The joining part 30 may contain a noble metal other than Ag as a main component.

  In this embodiment, the joining part 30 is comprised with resin (for example, thermosetting resin etc.) and the electroconductive filler which consists of Ag. As the thermosetting resin, for example, a phenol resin, an acrylic resin, a silicone resin, an epoxy resin, or a polyimide resin is used. The joint part 30 is also a conductive resin layer.

  The joining part 30 can be formed as follows. At least one of the second electrode layer 13 included in the electrode portion disposed on the end surface 3a of the external electrode 5 and the connection portion 21 of the metal terminal 20 is applied with the conductive adhesive in an uncured state, The external electrode 5 (second electrode layer 13) and the connection portion 21 (metal layer 27) are brought into contact with the conductive adhesive. The conductive adhesive is cured with the external electrode 5 and the connection portion 21 facing each other through the conductive adhesive. Thereby, the joint portion 30 is formed, and the external electrode 5 and the connection portion 21 are physically and electrically connected via the joint portion 30.

  As described above, in the present embodiment, the joint portion 30 contains the noble metal (Ag) as a main component, and the outermost layers (the second electrode layer 13 and the metal layer 27) of the external electrode 5 and the metal terminal 20. ) Contains noble metal (Ag). The noble metal is a metal that is relatively less likely to cause an alloy reaction and is more stable than Cu or the like from the viewpoint of alloying. Therefore, in the electronic component device ED1, a decrease in bonding strength via the bonding portion 30 between the external electrode 5 and the metal terminal 20 is suppressed even during continuous use in a high temperature environment.

  The second electrode layer 13 of the external electrode 5, the metal layer 27 of the metal terminal 20, and the joint portion 30 may contain inevitable trace amounts of impurities.

  As mentioned above, although embodiment of this invention has been described, this invention is not necessarily limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the summary.

  The second electrode layer 13 is not limited to a sintered metal layer, and may be a plating layer formed on the first electrode layer 11. That is, the second electrode layer 13 may be formed on the first electrode layer 11 by a plating method. In this case, the second electrode layer 13 is a noble metal plating layer (plating layer made of noble metal) formed on the first electrode layer 11 by noble metal plating. The noble metal plating layer includes an Ag plating layer, an Au plating layer, a Pt plating layer, or a Pd plating layer.

  The second electrode layer 13 may be a conductive resin layer formed on the first electrode layer 11. That is, the second electrode layer 13 may be formed by curing a conductive resin applied on the first electrode layer 11. In this case, the second electrode layer 13 is formed so as to cover the entire first electrode layer 11. The first electrode layer 11 is a base metal layer for forming the second electrode layer 13. As the conductive resin, a thermosetting resin (for example, the above-described epoxy resin) mixed with a conductive filler and an organic solvent is used. As the conductive filler, Ag powder, Au powder, Pt powder, Pd powder, or the like is used.

  When the second electrode layer 13 is a sintered metal layer or a plated layer, the joint is not limited to a conductive adhesive, but a sintered noble metal (for example, sintered Ag, sintered Au, sintered Pt). Or sintered Pd). In this case, the joining part 30 can be formed as follows. A conductive paste is applied to at least one of the second electrode layer 13 included in the electrode portion disposed on the end surface 3a of the external electrode 5 and the connection portion 21 of the metal terminal 20, and the external electrode is applied to the conductive paste. 5 (second electrode layer 13) and the connecting portion 21 (metal layer 27) are brought into contact with each other. The conductive paste is baked in a state where the external electrode 5 and the connection portion 21 face each other with the conductive paste interposed therebetween. Thereby, the external electrode 5 and the connection part 21 are physically and electrically connected via the joining part 30.

  The conductive paste for forming the joint portion 30 is made of a noble metal powder (for example, a powder made of Ag, a powder made of Au, a powder made of Pt, or a powder made of Pd), an organic binder, and an organic solvent. A mixture of these is used. That is, the joint part 30 is also a sintered metal layer formed by sintering a noble metal contained in the conductive paste.

  The metal layer 27 does not need to cover the entire base material 25. For example, the metal layer 27 may be formed only in a region facing the external electrode 5 in the connection portion 21.

  In the present embodiment, the multilayer capacitor 1 is described as an example of the electronic component, but the applicable electronic component is not limited to the multilayer capacitor 1. The applicable electronic component is, for example, a multilayer electronic component such as a multilayer inductor, a multilayer varistor, a multilayer piezoelectric actuator, a multilayer thermistor, or a multilayer composite component, or an electronic component other than the multilayer electronic component.

  DESCRIPTION OF SYMBOLS 1 ... Multilayer capacitor, 3 ... Element body, 5 ... External electrode, 11 ... 1st electrode layer, 13 ... 2nd electrode layer, 20 ... Metal terminal, 21 ... Connection part, 23 ... Leg part, 25 ... Base material, 27 ... Metal layer, 30 ... Junction, ED1 ... Electronic component device.

Claims (7)

An electronic component comprising an element body and an external electrode disposed on the element body;
A metal terminal electrically connected to the external electrode;
A joint portion that joins and electrically connects the external electrode and the metal terminal;
The outermost layer of the external electrode is a layer containing a noble metal;
The outermost layer of the metal terminal is a layer containing a noble metal;
An electronic component device in which the joint includes a precious metal as a main component.   The electronic component device according to claim 1, wherein the outermost layer of the metal terminal is a plating layer made of Ag.   The electronic component device according to claim 1, wherein the outermost layer of the external electrode is a sintered metal layer made of an AgPdCu alloy.   The electronic component device according to claim 1, wherein the outermost layer of the external electrode is a plating layer made of Ag.   The electronic component device according to claim 1, wherein the outermost layer of the external electrode is a conductive resin layer containing Ag.   The electronic component device according to any one of claims 3 to 4, wherein the joint portion is formed of a conductive adhesive whose conductive filler is made of Ag.   The electronic component device according to claim 3 or 4, wherein the joint portion is formed of sintered Ag.

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