JP2009176829A - Electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component that can suppress delamination and improve connectability between a lead-out electrode and an external electrode. <P>SOLUTION: A laminate is constituted by laminating a magnetic material layer. The internal electrode 8 is laminated together with the magnetic material layer. The external electrode is formed on a surface of the laminate. The lead-out electrode 9 electrically connects the internal electrode 8 and the external electrode to each other, and blank portions 16 which are exposed on a side surface while connected in one and where no electrode material is present are formed inside. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic component, and more particularly, to an electronic component including a laminate in which insulating layers are laminated.

  In the field of electronic components in which a plurality of insulating layers are laminated, various inventions have been proposed in order to prevent the occurrence of delamination. This delamination is particularly likely to occur at the boundary between the insulating electrode and the lead electrode for electrically connecting the element incorporated in the electronic component and the external electrode. This is because the extraction electrode and the insulating layer are formed of different materials, and the adhesion between the extraction electrode and the insulation layer is lower than the adhesion between the insulation layers.

  As a method for preventing the delamination, for example, it is conceivable to use an electronic component described in Patent Document 1. FIG. 7 is an enlarged view of the extraction electrode 100 of the electronic component described in Patent Document 1. As shown in FIG.

  As shown in FIG. 7, the extraction electrode 100 is provided with a plurality of slits 102. As described above, in the electronic component, by providing the slit 102 in the extraction electrode 100, the insulating layers come into contact with each other in the slit 102. As a result, in an electronic component to which the extraction electrode 100 is applied, delamination is less likely to occur at the boundary between the extraction electrode 100 and the insulating layer, compared to an electronic component having an extraction electrode without a slit.

However, an electronic component to which the extraction electrode 100 is applied has a problem that the connection between the extraction electrode 100 and the external electrode is poor. More specifically, the slit 102 is formed up to the end of the extraction electrode 100. Therefore, in the electronic component to which the extraction electrode 100 is applied, the contact area between the extraction electrode 100 and the external electrode is smaller than that of the electronic component having the extraction electrode in which the slit 102 is not formed. As a result, in an electronic component to which the extraction electrode 100 is applied, the connectivity between the extraction electrode 100 and the external electrode is deteriorated.
Japanese Patent Laid-Open No. 11-16759

  Accordingly, an object of the present invention is to provide an electronic component capable of suppressing the occurrence of delamination and improving the connectivity between the extraction electrode and the external electrode.

  The present invention provides an electronic component in which an insulating layer is laminated, an internal electrode laminated with the insulating layer, an external electrode formed on a side surface of the laminated body, the internal electrode, A lead electrode electrically connected to the external electrode, exposed from the side surface in a connected state, and a lead electrode in which a blank portion in which no electrode material is present is formed; It is characterized by providing.

  According to the present invention, the lead electrode is provided with a blank portion. In the blank portion, the insulating layers sandwiching the blank portion are in contact with each other. The adhesion between the insulating layers is higher than the adhesion between the insulating layer and the extraction electrode. Therefore, in the present invention, delamination is less likely to occur compared to an electronic component in which a blank portion is not provided in the extraction electrode.

  Furthermore, in the present invention, the extraction electrode is exposed in a connected state. Therefore, in the extraction electrode of the present invention, the area exposed from the laminated body is larger than the conventional extraction electrode shown in FIG. As a result, the contact area between the extraction electrode and the external electrode is increased, and the connectivity between the extraction electrode and the external electrode is improved.

  In the present invention, the blank portion may extend in a direction substantially perpendicular to the side surface where the extraction electrode is exposed.

  In the present invention, a plurality of the blank portions may be provided.

  In the present invention, the line width of the extraction electrode between the adjacent blank portions may be narrower than the line width of the internal electrode.

  In the present invention, the blank portion may be provided in a matrix.

  In the present invention, the extraction electrode may be formed thinner than the internal electrode.

  In the present invention, the internal electrode may constitute a coil or a capacitor.

  According to the present invention, since the blank portion is provided in the extraction electrode, delamination hardly occurs. Furthermore, in the present invention, since the extraction electrode is exposed in a connected state, the connectivity between the extraction electrode and the external electrode is improved.

  Hereinafter, an electronic component according to an embodiment of the present invention will be described. FIG. 1 is an external perspective view of the electronic component 10. FIG. 2 is an exploded view of the laminate 12 of the electronic component 10. FIG. 3 is an enlarged view of the extraction electrodes 9a and 9e. Hereinafter, the direction in which the ceramic green sheets are laminated when the electronic component 10 is formed is defined as the lamination direction. The stacking direction is the z-axis direction, the longitudinal direction of the electronic component 10 is the x-axis direction, and the direction orthogonal to the x-axis and the z-axis is the y-axis direction. The x axis, the y axis, and the z axis are parallel to the sides constituting the electronic component 10.

(About the configuration of electronic components)
As shown in FIG. 1, the electronic component 10 includes a rectangular parallelepiped laminated body 12 including a coil therein, and external electrodes 14 a and 14 b formed on the surface of the laminated body 12. The laminated body 12 has a rectangular parallelepiped shape. In FIG. 1, the surface of the laminated body 12 located at both ends in the z-axis direction is referred to as an upper surface S1 and a lower surface S2. Moreover, the surface of the laminated body 12 located at both ends in the y-axis direction is referred to as a side surface Sa and a side surface Sb. Furthermore, the surface of the laminated body 12 located at both ends in the x-axis direction is referred to as a side surface Sd and a side surface Se. The external electrodes 14a and 14b are formed so as to cover the side surfaces Sd and Se, respectively.

  The laminated body 12 is configured by laminating a plurality of internal electrodes and a plurality of magnetic layers together. Specifically, it is as follows. As shown in FIG. 2, the laminated body 12 is formed by laminating a plurality of magnetic layers 4a to 4e and 5a to 5f made of ferrite having high magnetic permeability (for example, Ni—Zn—Cu ferrite or Ni—Zn ferrite). It is constituted by. The plurality of magnetic layers 4a to 4e and 5a to 5f are rectangular insulating layers each having substantially the same area and shape.

  Internal electrodes 8a to 8e are formed on the main surfaces of the magnetic layers 4a to 4e, respectively. In addition, lead electrodes 9a and 9e are formed on the main surfaces of the magnetic layers 4a and 4e. Furthermore, via conductors Ba to Bd are formed in the magnetic layers 4a to 4d, respectively. In the following, when the individual magnetic layers 4a to 4e, 5a to 5f, the internal electrodes 8a to 8e, the lead electrodes 9a and 9e, and the via conductors Ba to Bd are shown, an alphabet is added after the reference symbol, When the body layers 4a to 4e, 5a to 5f, the internal electrodes 8a to 8e, the lead electrodes 9a and 9e, and the via conductors Ba to Bd are collectively referred to, the alphabet after the reference sign is omitted.

  As shown in FIG. 2, each internal electrode 8 is made of a conductive material made of Ag and has a “U” shape. However, the internal electrodes 8a and 8e arranged on the uppermost side and the lower side in the z-axis direction have an “L” shape. Thereby, one internal electrode 8 constitutes a part of the coil L corresponding to 3/4 turns. The internal electrode 8 may be made of a conductive material such as a noble metal containing Pd, Au, Pt or the like as a main component or an alloy thereof.

  As shown in FIG. 2, the via conductor B is made of a conductive material made of Ag, and is formed at one end of the internal electrode 8 so as to penetrate the magnetic layer 4 in the z-axis direction. Thereby, the via conductor B electrically connects the internal electrodes 8 adjacent in the z-axis direction. As a result, the plurality of internal electrodes 8 constitute a helical coil L.

  As shown in FIG. 2, each of the extraction electrodes 9a and 9e has a magnetic body so that one end is connected to the internal electrodes 8a and 8e and the other end is connected to one and exposed from the side surfaces Se and Sd. It is formed on the layers 4a and 4e. The lead electrodes 9a and 9e are electrically connected to the external electrodes 14b and 14a through portions exposed from the side surfaces Se and Sd of the multilayer body 12, respectively. Thereby, the extraction electrodes 9a and 9e electrically connect the internal electrodes 8a and 8e and the external electrodes 14b and 14a. The extraction electrodes 9a and 9e are formed thinner than the internal electrodes 8a and 8e, respectively.

  Further, as shown in FIG. 3, a plurality of blank portions 16a and 16e in which no electrode material exists are formed inside the extraction electrodes 9a and 9e, respectively. The blank portions 16a and 16e extend parallel to each other in a direction (x-axis direction) substantially perpendicular to the side surfaces Sd and Se, respectively. The blank portions 16a and 16e are formed such that the line width w of the extraction electrodes 9a and 9e between the adjacent blank portions 16a and 16e is narrower than the line width W of the internal electrodes 8a and 8e. In the blank portion 16a, the magnetic layer 5c and the magnetic layer 4a sandwiching the blank portion 16a are in contact with each other. Similarly, in the blank portion 16e, the magnetic layer 4d and the magnetic layer 4e sandwiching the blank portion 16e are in contact with each other. When the individual blank portions 16a and 16e are shown, an alphabet is added after the reference symbol, and when the blank portions 16a and 16e are collectively referred to, the alphabet after the reference symbol is omitted.

  The laminated body 12 is formed by stacking the magnetic layers 5a to 5c, 4a to 4e, and 5d to 5f in the exploded perspective view shown in FIG. 2 in this order from the upper side in the z-axis direction. Furthermore, when the external electrodes 14a and 14b are formed on the surface of the laminate 12, the electronic component 10 is obtained.

(About electronic component manufacturing methods)
Hereinafter, a method for manufacturing the electronic component 10 will be described with reference to FIGS. 1 and 2.

First, the ceramic green sheets to be the magnetic layers 4 and 5 are produced as follows. Ferric oxide (Fe ₂ O ₃ ) 49.0 mol%, zinc oxide (ZnO) 18.0 mol%, nickel oxide (NiO) 22.0 mol%, and copper oxide (CuO) 11.0 mol% Each material weighed in the above ratio is put into a ball mill as a raw material, and wet blending is performed. The obtained mixture is dried and pulverized, and the obtained powder is calcined at 800 ° C. for 1 hour. The obtained calcined powder is wet pulverized by a ball mill, dried and crushed to obtain a ferrite ceramic powder having a particle size of 2 μm.

  A binder (vinyl acetate, water-soluble acrylic, etc.), a plasticizer, a wetting material, and a dispersing agent are added to the ferrite ceramic powder, followed by mixing with a ball mill, and then defoaming is performed under reduced pressure. The obtained ceramic slurry is formed into a sheet by the doctor blade method and dried to produce a ceramic green sheet having a desired film thickness (for example, 50 μm).

  Next, via conductors Ba to Bd are formed in the ceramic green sheets to be the magnetic layers 4a to 4d, respectively. Specifically, a via hole is formed by irradiating a ceramic green sheet to be the magnetic layers 4a to 4d with a laser beam. Next, the via hole is filled with a conductive paste such as Ag, Pd, Cu, Au or an alloy thereof by a method such as printing.

  Next, a conductive paste mainly composed of Ag, Pd, Cu, Au, or an alloy thereof is applied to the ceramic green sheets to be the magnetic layers 4a to 4e by a method such as a screen printing method or a photolithography method. By coating, the internal electrode 8 and the extraction electrode 9 are formed. The via conductors Ba to Bd may be formed simultaneously with the formation of the internal electrode 8 and the extraction electrode 9.

  Next, each ceramic green sheet is laminated. Specifically, a ceramic green sheet to be the magnetic layer 5f is disposed. Next, the ceramic green sheet to be the magnetic layer 5e is placed and temporarily pressed onto the ceramic green sheet to be the magnetic layer 5f. Thereafter, the ceramic green sheets to be the magnetic layers 5d, 4e, 4d, 4c, 4b, 4a, 5c, 5b, and 5a are similarly laminated and temporarily pressed in this order. Thereby, a mother laminated body is formed. The mother laminate is subjected to main pressure bonding by a hydrostatic pressure press or the like.

  Next, the mother laminate is cut into a laminate 12 having a size of 2.0 mm × 1.25 mm × 1.25 mm by guillotine cutting. Thereby, the unfired laminated body 12 is obtained. The unfired laminate 12 is subjected to binder removal processing and firing. The binder removal treatment is performed, for example, in a low oxygen atmosphere at 500 ° C. for 2 hours. Firing is performed, for example, at 850 to 900 ° C. for 1.5 hours. Thereby, the baked laminated body 12 is obtained. External electrodes 14a and 14b are formed on the surface of the laminate 12 by applying and baking an electrode paste whose main component is silver by a method such as dipping. The external electrodes 14a and 14b are dried at 120 ° C. for 10 minutes, and the external electrodes 14a and 14b are baked at 780 ° C. for 2.5 hours. The external electrodes 14a and 14b are formed on the side surfaces Sd and Se, respectively, as shown in FIG.

  Finally, Ni plating / Sn plating is performed on the surfaces of the external electrodes 14a and 14b. Through the above steps, the electronic component 10 as shown in FIG. 1 is completed.

(effect)
According to the electronic component 10, the extraction electrodes 9 a and 9 e are exposed in a state of being connected to one from the side surfaces Sd and Se, and the blank portion 16 is provided inside the extraction electrode 9. Therefore, in the electronic component 10, as described below, it is possible to suppress the occurrence of delamination and improve the connectivity between the extraction electrode 9 and the external electrode 14.

  In the electronic component 10, as shown in FIG. 3, a blank portion 16 is provided in the extraction electrode 9. In the blank portion 16a, the magnetic layer 5c and the magnetic layer 4a sandwiching the blank portion 16a are in contact with each other. Similarly, in the blank portion 16e, the magnetic layer 4d and the magnetic layer 4e sandwiching the blank portion 16e are in contact with each other. The adhesion between the magnetic layers 4 and 5 is higher than the adhesion between the magnetic layers 4 and 5 and the extraction electrode 9. Therefore, in the electronic component 10, delamination is less likely to occur compared to an electronic component in which a blank portion is not provided in the extraction electrode.

  Furthermore, since the extraction electrodes 9a and 9e are formed thinner than the internal electrodes 8a and 8e, it is possible to more effectively suppress the occurrence of delamination at the boundary between the extraction electrode 9 and the magnetic layers 4 and 5.

  Furthermore, in the electronic component 10, as shown in FIG.2 and FIG.3, the extraction electrode 9 is exposed from the laminated body 12 in the state connected to one. Therefore, in the extraction electrode 9, the area exposed from the stacked body 12 is larger than that of the extraction electrode 100 shown in FIG. As a result, the contact area between the extraction electrode 9 and the external electrode 14 is increased, and the connectivity between the extraction electrode 9 and the external electrode 14 is improved.

  Further, in the extraction electrode 9 shown in FIG. 3, a plurality of blank portions 16 are formed so as to be parallel to each other so as to extend in the x-axis direction. Therefore, the extraction electrode 9 forms a plurality of current paths extending in the x-axis direction as indicated by arrows in FIG. As a result, the internal electrode 8 and the external electrode 14 can be connected by the extraction electrode 9 even if a defect occurs in a part of the extraction electrode 9 due to the formation failure of the extraction electrode 9.

  Further, since the blank portion 16 is provided in the lead electrode 9, the lead electrode 9 can be formed with less conductive paste than the lead electrode not provided with the blank portion.

(Modification)
The electronic component according to the present invention is not limited to the electronic component 10 according to the embodiment. Therefore, the design of the electronic component 10 may be changed as appropriate. Below, the electronic component 10 which concerns on a modification is demonstrated, referring drawings. FIG. 4 is an enlarged view of the extraction electrodes 9a and 9e of the electronic component 10 according to the first modification. FIG. 5 is an enlarged view of the extraction electrodes 9a and 9e of the electronic component 10 according to the second modification. In the extraction electrodes 9a and 9e shown in FIGS. 4 and 5, the same components as those of the extraction electrodes 9a and 9e in FIG.

  As with the extraction electrodes 9a and 9e shown in FIG. 4, a plurality of blank portions 16a and 16e may be provided so as to extend in the y-axis direction. Further, like the lead electrodes 9a and 9e shown in FIG. 5, a plurality of blank portions 16a and 16e may be provided in a matrix. In particular, in the extraction electrodes 9a and 9e shown in FIG. 5, a plurality of current paths are formed in the y-axis direction in addition to the x-axis direction. Therefore, even if a defect occurs in a part of the extraction electrode 9 due to poor formation of the extraction electrode 9, the internal electrode 8 and the external electrode 14 can be more reliably connected by the extraction electrode 9.

(Other embodiments)
The internal electrode 8 of the electronic component 10 may constitute an element other than the coil L. For example, the internal electrode 8 ′ may constitute a capacitor C as in the exploded perspective view of the multilayer body 12 ′ of the electronic component 10 ′ according to another embodiment shown in FIG. In this case, the internal electrode 8′a and the internal electrode 8′e are opposed to each other with the dielectric layer 4′a interposed therebetween. Then, when viewed in plan from the z-axis direction, portions protruding from the internal electrode 8 ′ become extraction electrodes 9′a and 9′e. The extraction electrodes 9′a and 9′e have a structure shown in FIGS.

1 is an external perspective view of an electronic component according to the present invention. It is an exploded view of the laminated body of the said electronic component. It is an enlarged view of an extraction electrode. It is an enlarged view of the extraction electrode of the electronic component which concerns on a 1st modification. It is an enlarged view of the extraction electrode of the electronic component which concerns on a 2nd modification. It is a disassembled perspective view of the laminated body of the electronic component which concerns on other embodiment. 6 is an enlarged view of an extraction electrode of an electronic component described in Patent Document 1. FIG.

Explanation of symbols

4a, 4b, 4c, 4d, 4e, 5a, 5b, 5c, 5d, 5e, 5f, 4'a, 4'e, 5'a, 5'b, 5'c, 5'd, 5'e, 5'f Magnetic layer 8a, 8b, 8c, 8d, 8e, 8'a, 8'e Internal electrode 9a, 9e, 9'a, 9'e Lead electrode 10 Electronic component 12, 12 'Laminated body 14a, 14b External electrode 16a, 16e Blank area

Claims (7)

A laminated body in which insulating layers are laminated;
An internal electrode laminated with the insulating layer;
An external electrode formed on a side surface of the laminate;
A lead electrode that electrically connects the internal electrode and the external electrode, and is exposed from the side surface in a connected state, and a blank portion in which no electrode material is present is formed inside. An extraction electrode;
Providing
Electronic parts characterized by The blank portion extends in a direction substantially perpendicular to the side surface where the extraction electrode is exposed;
The electronic component according to claim 1. A plurality of the blank portions are provided;
The electronic component according to claim 2. The line width of the lead electrode between the adjacent blank portions is narrower than the line width of the internal electrode;
The electronic component according to claim 3. The blank portions are provided in a matrix,
The electronic component according to claim 1. The extraction electrode is formed thinner than the internal electrode;
The electronic component according to claim 1, wherein: The internal electrode constitutes a coil or a capacitor;
The electronic component according to claim 1, wherein:

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