JP2007123355A - Electronic component manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component manufacturing method which can increase the dimensional accuracy of a terminal electrode. <P>SOLUTION: In this manufacturing method of electronic components, an end face 5a of a flange 5 with a conductive paste 10 attached thereto is in contact with the surface Sa of a porous Japanese paper S. Using the capillary phenomenon between the end face 5a of the flange 5 and the surface Sa of the Japanese paper S, the Japanese paper S is made to absorb the conductive paste 10 to uniformly remove excessive conductive paste 10 attaching to the end face 5a of the flange 5. Consequently, there is little variation in an attaching amount of the conductive paste 10 on the end face 5a of the flange 5, and thereby the dimensional accuracy of the terminal electrode 3 can be increased which is formed through a drying/baking process. The dimensional accuracy of the terminal electrode 3 increases the dimensional accuracy in the longitudinal direction of a coil component 1, making the coil component 1 very reliable one. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an electronic component such as a chip-type coil component.

In an electronic component such as a chip-type coil component, terminal electrodes are formed at both ends of a chip element body. As a technique for forming such a terminal electrode, for example, there is a method for manufacturing a ceramic electronic component described in Patent Document 1. In this conventional method of manufacturing a ceramic electronic component, the dent in the terminal electrode is adjusted by adjusting the speed at which the end of the chip body is immersed in the conductive paste tank and the speed at which the end of the chip body is pulled up from the conductive paste tank. To prevent generation of bubbles and mixing of bubbles.
JP 2003-59786 A

  By the way, when the end of the chip body is immersed in the conductive paste tank, the conductive paste may adhere to the end surface of the chip body. In this case, for example, the amount of excess conductive paste attached may vary depending on the depth at which the end of the chip body is immersed in the conductive paste tank. There may be a problem that the dimensional accuracy of the electrode is lowered. In contrast, the above-described conventional method for manufacturing a ceramic electronic component does not include a step of adjusting the amount of conductive paste attached to the end face of the chip body, and it is difficult to improve the dimensional accuracy of the terminal electrode. there were.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an electronic component manufacturing method capable of improving the dimensional accuracy of the terminal electrode.

  In order to solve the above-described problems, an electronic component manufacturing method according to the present invention is a method for manufacturing an electronic component having terminal electrodes at both ends of an element body, in a conductive paste that is a material for forming terminal electrodes. It comprises a step of immersing the end of the element body and a step of bringing the end surface of the element body to which the conductive paste is adhered into contact with the surface of the porous material.

  In this electronic component manufacturing method, the end face of the element body to which the conductive paste is attached is brought into contact with the surface of the porous material. At this time, since a capillary phenomenon due to the surface tension of the conductive paste occurs between the end face of the element body and the surface of the porous material, excess conductive paste is uniformly distributed from the end face of the element body by the porous material. Removed. As a result, the adhesion amount of the conductive paste hardly varies at the end face of the element body, and the dimensional accuracy of the terminal electrode formed through the drying / baking process can be improved.

  The porous material is preferably Japanese paper. In this case, excess conductive paste can be removed quickly and reliably from the end face of the element body. Examples of Japanese paper include calligraphic paper (half paper), shoji paper, and the like.

  As described above, according to the electronic component manufacturing method of the present invention, the dimensional accuracy of the terminal electrode can be improved. This makes it possible to obtain a highly reliable electronic component.

  Hereinafter, preferred embodiments of an electronic component manufacturing method according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing a coil component which is an example of an electronic component manufactured by a method for manufacturing an electronic component according to an embodiment of the present invention. 2 is a cross-sectional view taken along line II-II in FIG.

  As shown in FIGS. 1 and 2, the coil component 1 includes a substantially rectangular parallelepiped core (element body) 2 and terminal electrodes 3 and 3 formed at both ends of the core 2 in the longitudinal direction. It is comprised as a chip-type coil component. The core 2 is a so-called drum-type core including a substantially quadrangular columnar core 4 and a pair of rectangular parallelepiped flange portions 5 and 5 formed at both ends of the core 4.

  As shown in FIG. 2, the core 4 and the flange 5 are integrally formed of a magnetic material such as ferrite, for example, and a coil 6 is formed on the peripheral surface of the core 4 by winding a conductive wire. ing. The periphery of the core 4 is filled with a protective layer 7 made of resin for protecting the coil 6.

  The terminal electrodes 3 and 3 have a two-layer structure including an inner electrode 8 and an outer electrode 9. The inner electrode 8 is formed so as to cover the end surface 5a of the flange portion 5 and the side surfaces 5b by sintering a conductive paste containing Ag, for example. The inner electrode 8 has a thickness of about 20 μm to about 30 μm. Although not shown, both ends of the coil 6 are electrically connected to the inner electrodes 8 by, for example, thermocompression bonding.

  The outer electrode 9 is formed so as to cover the inner electrode 8 by sintering a conductive paste containing Ag, for example. The thickness of the outer electrode 9 is smaller than the thickness of the inner electrode 8 on the end surface 5 a side of the flange portion 5. A metal plating layer (not shown) having a thickness of about 30 μm is formed on the surface of the outer electrode 9 by, for example, a wet plating method. The outer electrode 9 overlaps the boundary portion between the side surface of the inner electrode 8 and the surface of the protective layer 7, thereby protecting the thermocompression bonding portion between the both end portions of the coil 6 and each inner electrode 8. It also has a function.

  Next, the manufacturing method of such a coil component 1 is demonstrated.

  First, the core 2 before forming the terminal electrode 3 is prepared, and the inner electrode 8 is formed in advance so as to cover the end surface 5a and the side surfaces 5b of the flange portion 5. Next, after the coil 6 is wound and pressed and the protective layer 7 is formed, for example, by using a dipping method (dipping method) or the like, the outer electrode 9 is provided around the inner electrode 8 as shown in FIG. The conductive paste 10 for forming the film is applied.

  When the conductive paste 10 is applied, as shown in the figure, when the conductive paste 10 is excessively attached to the end surface of the core 2, that is, the end surface 5a of the flange portion 5 so as to rise from the end surface 5a. There is. The amount of the extra conductive paste 10 attached may vary depending on, for example, the depth at which the flange 5 is immersed in the conductive paste 10. There may be a problem of reduced accuracy.

  On the other hand, in this electronic component manufacturing method, as shown in FIG. 4, after applying the conductive paste 10 to the end surface 5a of the flange 5, the end surface 5a of the flange 5 is applied to the Japanese paper S (porous material). Is brought into contact with the surface Sa. At this time, a capillary phenomenon due to the surface tension of the conductive paste 10 occurs between the end surface 5a of the collar portion 5 and the surface Sa of the Japanese paper S, and an excessive conductive paste adhering to the end surface 5a of the collar portion 5 is generated. Absorbed by Japanese paper S.

  Thereby, when the core 2 is pulled up from the Japanese paper S, as shown in FIG. 5, the conductive paste 10 on the end surface 5 a of the collar portion 5 is uniformly attached with a thickness smaller than the thickness of the inner electrode 8. Become. Thereafter, the outer electrode 9 is formed through a predetermined drying / baking process, whereby the chip-type coil component 1 shown in FIGS. 1 and 2 is completed.

  As described above, in this method of manufacturing an electronic component, the end surface 5a of the collar portion 5 to which the conductive paste 10 is adhered is brought into contact with the surface Sa of the Japanese paper S that is a porous material. Then, the conductive paper 10 is absorbed by the Japanese paper S using the capillary phenomenon that occurs between the end surface 5a of the collar portion 5 and the surface Sa of the Japanese paper S at the time of contact, and adheres to the end surface 5a of the collar portion 5. The excess conductive paste 10 is removed uniformly. As a result, the adhesion amount of the conductive paste 10 hardly varies at the end surface 5a of the flange portion 5, and the dimensional accuracy of the terminal electrode 3 formed through the drying and baking processes can be improved. This increases the dimensional accuracy in the longitudinal direction of the coil component 1 and enables the manufacture of the highly reliable coil component 1.

  Moreover, in this electronic component manufacturing method, since the Japanese paper S is used as the porous material, the excess conductive paste 10 can be quickly and surely removed from the end surface 5a of the flange portion 5. As such Japanese paper, for example, calligraphy paper (half paper), shoji paper or the like can be used. In the above embodiment, the conductive paste 10 is not completely removed from the end surface 5a of the collar portion 5 by the Japanese paper S, but remains uniformly with a thickness smaller than the thickness of the inner electrode 8. Thereby, the mounting strength at the time of mounting the coil component 1 is ensured.

  The present invention is not limited to the above embodiment. For example, this electronic component manufacturing method is not limited to the coil component 1 illustrated in the above embodiment, but can be applied to other chip-type electronic components such as a multilayer capacitor and a multilayer inductor. Moreover, in the said embodiment, although the Japanese paper S was illustrated as a porous material, it replaces with the Japanese paper S and sponge material, cloth, a metal mesh, a dimple (dimple) processed material, etc. can also be utilized.

It is a perspective view which shows the coil component which is an example of the electronic component manufactured by the manufacturing method of the electronic component which concerns on one Embodiment of this invention. It is the II-II sectional view taken on the line in FIG. It is a figure which shows the manufacturing process of the coil components shown in FIG. FIG. 4 is a diagram showing a manufacturing process subsequent to FIG. 3. FIG. 5 is a diagram showing a manufacturing process subsequent to FIG. 4.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Coil component (electronic component), 2 ... Core (element | base_body), 3 ... Terminal electrode, 5 ... A collar part (edge part of an element | base_body), 5a ... End surface, 10 ... Conductive paste, S ... Japanese paper (porous) Material), Sa ... surface.

Claims (2)

A method of manufacturing an electronic component having terminal electrodes at both ends of an element body,
A step of immersing the end of the element body in a conductive paste which is a forming material of the terminal electrode;
And a step of bringing the end face of the element body to which the conductive paste is adhered into contact with the surface of a porous material.   The method for manufacturing an electronic component according to claim 1, wherein the porous material is Japanese paper.

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