JP2009170446A - Electronic component and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component which is easily manufactured and has an inductor reducing a resistance value built in, and to provide a method of manufacturing the same. <P>SOLUTION: A laminate 12 includes a plurality of magnetic substance layers 4 and 5 which are layered. Two external electrodes are formed on a side face of the laminate 12. A plurality of internal electrodes 8 constitute the inductor and are formed on the magnetic substance layer 4 so that both ends are electrically connected with the two external electrodes. Via conductors Ba-Bd electrically connect the plurality of internal electrodes 8a-8d. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic component and a method for manufacturing the same, and more particularly to an electronic component including a laminated body in which insulating layers are stacked and a method for manufacturing the same.

  As a method of manufacturing an electronic component that can reduce DC resistance without reducing impedance, a method of manufacturing a multilayer bead inductor described in Patent Document 1 has been proposed. In the method of manufacturing the multilayer bead inductor, a long and narrow hole is formed in a magnetic green sheet using a dicer, and a conductive paste is embedded in the long hole. A multilayer bead inductor having a rectangular parallelepiped through conductor is obtained by laminating a plurality of layers of the magnetic green sheets and forming external electrodes.

By the way, the manufacturing method of the multilayer bead inductor described in Patent Document 1 has a problem that the process becomes complicated. More specifically, in the method of manufacturing the multilayer bead inductor, as described above, it is necessary to form a long hole in the magnetic green sheet using a dicer or the like. In forming such a long hole, it is possible to cut the long side with a dicer, but it is difficult to cut the short side with a dicer.
JP-A-6-61084

  Accordingly, an object of the present invention is to provide an electronic component including an inductor that can be easily manufactured and that can reduce a resistance value, and a method for manufacturing the electronic component.

  According to a first aspect of the present invention, in an electronic component, an inductor is formed by a laminated body in which a plurality of insulating layers are laminated, a first external electrode and a second external electrode formed on a side surface of the laminated body. And a plurality of internal electrodes formed on the insulating layer such that both ends are electrically connected to the first external electrode and the second external electrode, and the plurality of internal electrodes And a via conductor that is electrically connected.

  According to the first invention, the internal electrodes are electrically connected by the via conductor. The via conductor is formed by forming a via hole in the insulating layer and filling the via hole with a conductive paste. Furthermore, since the via hole is generally formed by irradiating the insulating layer with a laser beam, a long hole is formed using a dicer as in the method of manufacturing a multilayer bead inductor described in Patent Document 1. There is no need to form. As a result, the manufacture of electronic components can be facilitated.

  In the first invention, the plurality of internal electrodes may be arranged so as to overlap when viewed in plan from the stacking direction.

  In the first invention, the plurality of internal electrodes may have the same shape.

  In the first invention, the laminated body has a rectangular parallelepiped shape, and the first external electrode and the second external electrode are respectively a first side surface and a second side extending in the longitudinal direction of the laminated body. It may be formed on the side surface.

  In the first invention, the via conductors may be arranged in a checkered pattern in the insulating layer when viewed in plan from the stacking direction.

  In the first invention, the insulating layer in which the via conductor is formed may be a nonmagnetic layer.

  According to a second aspect of the present invention, in the method for manufacturing an electronic component, a step of forming a via conductor in the insulating layer, and a step of forming an internal electrode drawn out on two sides in each of the plurality of rectangular insulating layers, And a step of forming a laminate by laminating the insulating layers so that the plurality of internal electrodes are electrically connected by the via conductors.

  In the second invention, the step of forming the via conductor includes a step of irradiating the insulating layer with a laser beam to form a via hole, and a step of filling the via hole with a conductive paste. You may go out.

  In the second invention, the step of filling the via hole with a conductive paste and the step of forming the internal electrode may be performed simultaneously.

  In the second invention, in the step of forming the internal electrodes, the plurality of internal electrodes having the same shape may be formed.

  In the second invention, in the step of forming the stacked body, the insulating layer may be stacked so that the plurality of internal electrodes overlap when viewed in plan from the stacking direction.

  2nd invention WHEREIN: You may further provide the process of forming a 1st external electrode and a 2nd external electrode in the side surface of the said laminated body from which the said internal electrode is pulled out.

  In the second invention, in the step of forming the first external electrode and the second external electrode, the first external electrode and the second external electrode are respectively formed in the longitudinal direction of the rectangular parallelepiped laminate. You may form in the 1st side surface and 2nd side surface which are extended to.

  In the second invention, in the step of forming the via conductor, the insulating layer may be arranged in a checkered pattern when viewed in plan from the stacking direction.

  In the second invention, in the step of forming the via conductor, the via conductor may be formed in the insulating layer which is a non-magnetic layer.

  According to the present invention, since the internal electrodes are electrically connected by the via conductor, the manufacture of the electronic component can be facilitated.

  Below, the electronic component which concerns on one Embodiment of this invention, and its manufacturing method are demonstrated. FIG. 1 is an external perspective view of the electronic component 10. FIG. 2 is an exploded perspective view of the laminate 12. Hereinafter, the direction in which the ceramic green sheets are laminated when the electronic component 1 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 inductors and external electrodes 14a and 14b. 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 which is located at both ends in the y-axis direction and extends so as to have a longitudinal direction in the x-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 Sa and Sb, 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 4 a to 4 e and 5 a to 5 f made of high permeability ferrite (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. Further, a plurality of 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 and the via conductors Ba to Bd are shown, an alphabet is added after the reference symbol, and the magnetic layers 4a to 4e and the via conductors Ba to Bd are collectively referred to. Shall omit the alphabet after the reference sign.

  Each of the internal electrodes 8 is made of a conductive material made of Ag, constitutes an inductor, and one magnetic layer 4 is formed so that both ends thereof are electrically connected to the external electrode 14a and the external electrode 14b. Formed on top. That is, the internal electrode 8 is not formed across the plurality of magnetic layers 4. In the present embodiment, each internal electrode 8 is a linear electrode, and is formed on the magnetic layer 4 so as to extend in a direction perpendicular to the side surface Sa. Each internal electrode 8 has the same shape. Further, the vicinity of both ends of the internal electrode 8 is formed thicker than the other portions in order to improve the reliability of connection with the external electrodes 14a and 14b. Note that the shapes of the internal electrodes 8 do not necessarily have to be completely matched. The internal electrode 8 may have variations due to manufacturing errors, for example.

  The via conductor B is made of a conductive material made of Ag, is formed so as to penetrate the magnetic layer 4 in the z-axis direction, and electrically connects the internal electrodes 8 facing each other. A plurality of via conductors B are provided in the magnetic layer 4 so as to be arranged in two rows in the y-axis direction.

  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. At this time, the magnetic layers 4 and 5 are laminated so that the internal electrodes 8a to 8e overlap when viewed in plan from 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. Ferrous oxide (Fe ₂ O ₃ ), zinc oxide (ZnO), nickel oxide (NiO), and copper oxide (CuO) were weighed at a predetermined ratio and each material was put into a ball mill as a raw material. I do. 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 on the ceramic green sheets to be the magnetic layers 4a to 4d. 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, on the ceramic green sheets to be the magnetic layers 4a to 4e, a conductive paste mainly composed of Ag, Pd, Cu, Au, or an alloy thereof is applied by a method such as a screen printing method or a photolithography method. Is applied to form internal electrodes 8a to 8e having a line width of 500 μm. At this time, in each of the magnetic layers 4a to 4e, the internal electrodes 8a to 8e are formed so as to be drawn out to two sides (a front side and a back side in the y-axis direction). In the present embodiment, the internal electrodes 8a to 8e are formed to have the same shape. Note that the step of forming the internal electrodes 8a to 8d and the step of filling the via hole with the conductive paste may be performed simultaneously.

  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. When the ceramic green sheets to be the magnetic layers 4d, 4c, 4b, and 4a are laminated, the ceramic greens are arranged so that the internal electrodes 8 facing each other are electrically connected by the via conductors Ba to Bd. Laminate sheets. For example, as shown in FIG. 2, a ceramic green sheet to be the magnetic layer 4 may be laminated so that the internal electrodes 8 overlap when viewed in plan from the z-axis direction. 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 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 890 ° C. for 2.5 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 800 ° C. for 60 minutes. The external electrodes 14a and 14b are formed on the side surfaces Sa and Sb, respectively, as shown in FIG. The internal electrodes 8a to 8e are electrically connected to the external electrode 14a and the external electrode 14b.

  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 and the manufacturing method thereof, the internal electrode 8 is electrically connected by the via conductor B. The via conductor B is formed by forming a via hole in the magnetic layer 4 and filling the via hole with a conductive paste. In general, the via hole is formed by irradiating the magnetic layer 4 with a laser beam. Therefore, as in the method of manufacturing a multilayer bead inductor described in Patent Document 1, a long hole is formed using a dicer. There is no need to form. That is, the via hole can be easily formed as compared to the long hole. As a result, according to the electronic component 10 and the manufacturing method thereof, the electronic component 10 can be easily manufactured.

  Also, by providing the via conductor B, the resistance value of the electronic component 10 can be reduced. Furthermore, by providing the via conductor B, it is possible to increase the inductance of the electronic component 10 by reducing the number of the internal electrodes 8 while keeping the resistance value of the electronic component 10 low.

  In addition, as shown in FIG. 2, by forming a large number of via conductors B in the magnetic layer 4, the resistance value of the electronic component 10 can be further reduced.

  According to the electronic component 10, as shown in FIG. 1, external electrodes 14a and 14b are formed on side surfaces Sa and Sb extending in the longitudinal direction. Therefore, in the electronic component 10, the distance between the external electrode 14a and the external electrode 14b is smaller than when the external electrodes 14a and 14b are formed on the side surfaces Sd and Se. As a result, the length of the internal electrode 8 that connects the external electrode 14a and the external electrode 14b can be shortened, and the resistance value of the electronic component 10 can be reduced. In particular, in the present embodiment, the internal electrode 8 extends linearly in a direction perpendicular to the side surface Sa. Therefore, the length of the internal electrode 8 is the shortest. As a result, the resistance value of the electronic component 10 can be reduced more effectively.

  Further, according to the electronic component 10, as shown in FIG. 1, the external electrodes 14a and 14b are formed on the side surfaces Sa and Sb extending in the longitudinal direction. Therefore, in the electronic component 10, the external electrodes 14a and 14b can be made larger than when the external electrodes 14a and 14b are formed on the side surfaces Sd and Se. When the electronic component 10 is mounted on the circuit board, the contact area between the circuit board and the external electrodes 14a and 14b increases. As a result, the heat dissipation of the electronic component 10 is improved.

(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. Hereinafter, an electronic component according to a modification will be described with reference to the drawings. FIG. 3 is an exploded perspective view of an electronic component laminate 12a according to a modification. In the laminated body 12a of FIG. 3, the same reference numerals are assigned to the same components as those of the laminated body 12 of FIG.

  In the multilayer body 12 shown in FIG. 2, the via conductors B are formed so as to be arranged in two rows in the y-axis direction in the magnetic layer 4 when viewed in plan from the z-axis direction. On the other hand, in the laminated body 12a shown in FIG. 3, the via conductors B are arranged in a checkered pattern when viewed in plan from the z-axis direction. By arranging the via conductor B as shown in FIG. 3, it is possible to improve the DC superposition characteristics of the electronic component 10 as described below with reference to the drawings. FIG. 4 is an explanatory view of the electronic component 10 including the stacked body 12a shown in FIG. 3 as viewed in plan from the x-axis direction.

  In the laminated body 12a shown in FIG. 3, since the via conductors B are arranged in a checkered pattern, the interval between the via conductors B adjacent in the y-axis direction is larger than that of the laminated body 12 shown in FIG. . Therefore, in the multilayer body 12a shown in FIG. 3, the diameter of the via conductor B can be made larger than that of the multilayer body 12 shown in FIG. Therefore, as shown in FIG. 4, when viewed in plan from the x-axis direction, the area occupied by the via conductor B in the region sandwiched between the internal electrodes 8 can be increased. Since the magnetic flux is blocked by the via conductor B, the magnetic flux density in the region sandwiched between the internal electrodes 8 is smaller in the laminated body shown in FIG. 3 than in the laminated body shown in FIG. As a result, the occurrence of magnetic saturation in the region sandwiched between the internal electrodes 8 is suppressed, and the DC superposition characteristics of the electronic component 10 are improved.

  Further, in the multilayer bodies 12 and 12a shown in FIGS. 2 and 3, the magnetic body layer 4 in which the via conductor B is formed may be a non-magnetic body layer. Thereby, the occurrence of magnetic saturation in the region sandwiched between the internal electrodes 8 is more effectively suppressed, and the direct current superimposition characteristics of the electronic component 10 can be further improved.

1 is an external perspective view of an electronic component according to the present invention. It is a disassembled perspective view of the laminated body of the said electronic component. It is a disassembled perspective view of the laminated body of the electronic component which concerns on a modification. It is explanatory drawing which planarly viewed the electronic component containing the laminated body shown in FIG. 3 from the x-axis direction.

Explanation of symbols

4a, 4b, 4c, 4d, 4e, 5a, 5b, 5c, 5d, 5e, 5f Magnetic layer 8a, 8b, 8c, 8d, 8e Internal electrode 10 Electronic component 12, 12a Laminated body 14a, 14b External electrode Ba, Bb, Bc, Bd Via conductor

Claims (15)

A laminate formed by laminating a plurality of insulating layers;
A first external electrode and a second external electrode formed on a side surface of the laminate;
A plurality of internal electrodes formed in the insulating layer so that both ends thereof are electrically connected to the first external electrode and the second external electrode;
Via conductors electrically connecting the plurality of internal electrodes;
Having
Electronic parts characterized by The plurality of internal electrodes are arranged so as to overlap when viewed in plan from the stacking direction,
The electronic component according to claim 1. The plurality of internal electrodes have the same shape;
The electronic component according to claim 2. The laminate is a rectangular parallelepiped,
The first external electrode and the second external electrode are respectively formed on a first side surface and a second side surface extending in a longitudinal direction of the multilayer body;
The electronic component according to any one of claims 1 to 3, wherein: The via conductors are arranged in a checkered pattern in the insulating layer when viewed in plan from the stacking direction;
The electronic component according to claim 1, wherein: The insulating layer in which the via conductor is formed is a non-magnetic layer;
The electronic component according to claim 1, wherein: Forming a via conductor in the insulating layer;
Forming an internal electrode drawn out on two sides in each of a plurality of rectangular insulating layers;
Laminating the insulating layers to form a laminate so that the plurality of internal electrodes are electrically connected by the via conductors;
Having
A method of manufacturing an electronic component characterized by the above. The step of forming the via conductor includes
Irradiating the insulating layer with a laser beam to form a via hole;
Filling the via hole with a conductive paste;
Including
The manufacturing method of the electronic component of Claim 7 characterized by these. The step of filling the via hole with a conductive paste and the step of forming the internal electrode are performed simultaneously;
The method of manufacturing an electronic component according to claim 8. Forming the plurality of internal electrodes having the same shape in the step of forming the internal electrodes;
A method for manufacturing an electronic component according to claim 7, wherein: In the step of forming the laminate, the insulating layer is laminated so that the plurality of internal electrodes overlap when viewed in plan from the lamination direction;
The method for manufacturing an electronic component according to claim 7, wherein: Forming a first external electrode and a second external electrode on a side surface of the laminate from which the internal electrode is drawn,
More
The method of manufacturing an electronic component according to claim 7, wherein: In the step of forming the first external electrode and the second external electrode, each of the first external electrode and the second external electrode extends in the longitudinal direction of the rectangular parallelepiped laminate. Forming on the side surface and the second side surface,
The method of manufacturing an electronic component according to claim 12. In the step of forming the via conductor, when viewed in plan from the stacking direction, the insulating layer is arranged in a checkered pattern,
The method of manufacturing an electronic component according to claim 7, wherein In the step of forming the via conductor, forming the via conductor in the insulating layer that is a non-magnetic layer;
The method for manufacturing an electronic component according to claim 7, wherein

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