JP2007188957A - Surface-mounting electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface-mounting electronic component that can realize improvement in integration density, and can also control generation of fault in solder fillet. <P>SOLUTION: In a coil component 1, side surfaces 2c, 2c of a coil structure 2 are inclined and a cross-section of the coil structure 2 is formed in the shape of a trapezoid that is extending toward the opposing surface 2b from the side of mounting surface 2a. Therefore, since a forming tolerance of solder fillet may be provided in a space formed by a circuit board and the side surfaces 2c, 2c on the occasion of mounting to the circuit board in the coil component 1, an interval to the adjacent other electronic components may be reduced at the time of mounting and thereby improvement in integration efficiency can be realized. In addition, since an opening angles formed by the circuit board and the side surfaces 2c, 2c are respectively formed as acute angles, generation of fault such as crack in the solder fillet can be restricted even when a bending stress, etc. is applied to the circuit board. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a surface mount electronic component.

As a technique related to this type of field, for example, there is a multilayer ceramic capacitor described in Patent Document 1. This conventional multilayer ceramic capacitor has a ceramic element having a cross-sectional shape that expands toward the mounting surface when mounted on a substrate, thereby improving mounting stability.
JP-A-9-260184

  However, in the above-described conventional multilayer ceramic capacitor, it is necessary to secure a margin for forming a solder fillet used for board mounting around a mounting surface having a large area. There was a limit. In addition, since the open angle formed by the substrate and the side surface of the ceramic element is an obtuse angle, there is a problem in that defects such as cracks are likely to occur in the solder fillet when stress such as bending is applied to the substrate. If such a problem occurs, the electrical connection between the element and the substrate is broken, and the function as an electronic component may be lost.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a surface-mounted electronic component that can improve the integration efficiency and suppress the occurrence of defects in the solder fillet.

  In order to solve the above problems, a surface-mount electronic component according to the present invention includes a mounting surface, a facing surface facing the mounting surface, and an element body having a side surface intersecting the mounting surface and the facing surface. A surface-mounted electronic component having a terminal electrode provided, the side surface of which is inclined so that the cross-sectional shape of the element body extends from the mounting surface side to the opposing surface side, Is characterized by having an electrode portion formed on a side surface.

  In this surface mount type electronic component, the side surface of the element body is inclined so that the cross-sectional shape of the element body becomes wider from the mounting surface side toward the opposing surface side. It is possible to provide a margin for forming a solder fillet in a space formed by the side surface of the element body. As a result, in the surface-mounted electronic component, it is possible to reduce the interval between other electronic components adjacent to each other at the time of mounting, and it is possible to improve the integration efficiency. In addition, since the open angle formed by the substrate and the side surface of the element body is an acute angle, the load on the solder fillet can be suppressed even when a stress such as bending is applied to the substrate, and there is a problem such as a crack in the solder fillet. Generation can be suppressed.

  In addition, it is preferable that another side surface that is adjacent to the side surface and intersects the mounting surface and the opposing surface is further provided, and the electrode portion is formed apart from a boundary line between the side surface and the other side surface. In this way, when the side electrode portion is formed, a phenomenon (film blur) in which the electrode film wraps around the other surface of the element body can be suppressed.

  The cross-sectional shape of the element body is preferably a trapezoid. In this case, the element body can be easily manufactured by dicing or the like, and the cost of the electronic component can be reduced.

  Moreover, it is preferable that a terminal electrode further has the electrode part formed in the mounting surface following the electrode part. In this case, since the area of the terminal electrode can be sufficiently secured, the solder adhesion strength at the time of board mounting can be sufficiently secured.

  Moreover, it is preferable that the electrode part formed in the mounting surface is formed away from the boundary line between the mounting surface and the other side surface. In this case, film blurring at the time of forming the electrode portion on the mounting surface can be suppressed.

  Moreover, it is preferable that two or more side surfaces are formed. In this case, even when the electronic component is expanded to a multi-terminal product, the above-described effects can be exhibited.

  As described above, according to the surface mount electronic component according to the present invention, it is possible to improve the integration efficiency and to suppress the occurrence of defects in the solder fillet.

  Hereinafter, preferred embodiments of a surface mount electronic component according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view of a coil component shown as an embodiment of a surface mount electronic component according to the present invention. 2 is a side view of the coil component shown in FIG. 1, and FIG. 3 is a view of the coil component as viewed from the mounting surface side.

  As shown in FIGS. 1 to 3, the coil component 1 includes a flat core structure (element body) 2 and a pair of terminal electrodes 3 and 3. As shown in FIG. 8, the pair of terminal electrodes 3 and 3 are electrically connected to a member (for example, the electrode pad 19 a of the circuit board 19) on which the coil component 1 is mounted. The bottom surface of the core structure 2 is a mounting surface 2a that faces the circuit board 19 when the core structure 2 is mounted, and the top surface of the core structure 2 is opposite to the facing surface 2b that faces the mounting surface 2a. It has become.

  Further, in the core structure 2, the side surfaces 2c and 2c and the other side surfaces 2d and 2d facing each other are such that the cross-sectional shape of the core structure 2 spreads from the mounting surface 2a side to the facing surface 2b side. It is inclined to become. Thereby, in the core structure 2, the cross-sectional shape in the direction intersecting with the mounting surface 2a and the facing surface 2b has, for example, a lower base of about 2.3 mm, an upper base of about 2.5 mm, and a height of about 0.8 mm. It has a trapezoidal shape.

  The core structure 2 is configured by coupling a bridge-type ferrite core 4B to a ferrite core 4A that constitutes the mounting surface 2a side, whereby a substantially closed magnetic circuit is provided in an outer portion of the core structure 2. Is formed. Between the ferrite core 4A and the ferrite core 4B, as shown in FIG. 4, a flat air gap S penetrating from one side of the side surfaces 2c and 2c to the other is formed. A coil substrate 8 is fixed via an adhesive layer 7.

  As shown in FIG. 5, the coil substrate 8 has a substantially square shape, and a circular opening 9 for inserting an inner leg portion (not shown) of the ferrite core 4 </ b> A is inserted at a substantially center of the coil substrate 8. Is formed. Lead-out end electrodes 10 are respectively formed at the corners on both sides of the coil substrate 8.

  On both surfaces of the coil substrate 8, spiral coils 11, 11 surrounding the opening 9 are formed by plating and growing a conductive material such as Cu. One end portions of the coils 11, 11 on both sides are electrically connected to each other via a contact portion 12 provided on the peripheral portion of the opening 9, and the other end portions of the coils 11, 11 are connected to one side of the coil substrate 8. The lead-out end electrode 10 provided on the other side and the lead-out end electrode 10 provided on the other side are respectively electrically connected.

  As shown in FIGS. 1 to 3, each of the terminal electrodes 3 and 3 has a boundary portion between the side surface 2c and the opposite surface 2b from the boundary portion between the mounting surface 2a and the side surface 2c along the side surface 2c where the gap S faces. And an electrode portion 3b formed on the edge of the mounting surface 2a continuously to the electrode portion 3a. A plurality of plating layers (not shown) made of, for example, Cu, Ni, Sn, or the like are formed on the surfaces of the terminal electrodes 3 and 3.

  The electrode portion 3a and the electrode portion 3b are integrally formed by sputtering of a conductor material such as Cu or Cr. As shown in FIG. 3, the electrode portion 3a is formed away from the boundary line L1 between the side surface 2c and the other side surface 2d, and the electrode portion 3b is formed from the boundary line L2 between the mounting surface 2a and the other side surface 2d. They are spaced apart.

  The electrode portion 3a is formed so as to completely cover the gap S, and each lead-out end electrode 10 of the coil substrate 8 is electrically connected to the electrode portion 3a. Therefore, when a predetermined voltage is applied to the lead-out end electrodes 10 and 10 provided on one and the other sides of the coil substrate 8 via the terminal electrodes 3 and 3, they are formed on both surfaces of the coil substrate 8. A current is generated in the coils 11 and 11.

  Next, a method for manufacturing the coil component 1 having the above-described configuration will be described with reference to FIGS.

  First, as shown in FIG. 6A, for example, a flat base material 13 in which the core structure 2 and the coil substrate 8 are formed in a 6 × 6 matrix is prepared, and the mounting surface 2 a in the core structure 2 is planned. The base material 13 is placed on the dicing tape 14 so that the side faces upward. Next, as shown in FIG. 6B, by dicing, grooves 16 having a V-shaped cross section having a predetermined depth are formed in a lattice shape from the planned mounting surface 2a side of the base material 13, and each core structure 2 is formed. Separate from each other.

  After the groove 16 is formed, each lead-out end electrode 10 exposed on the surface of the groove 16 is cleaned. That is, the surface treatment by plasma is performed through each step of degreasing, dilute sulfuric acid cleaning, water cleaning, IPA (isopropyl alcohol) cleaning and drying of each lead-out electrode 10. After cleaning each lead-out electrode 10, as shown in FIG. 7A, a mask 17 having a predetermined pattern is disposed on the planned mounting surface 2a side of the base material 13, and the mounting surface 2a of each core structure 2 and Terminal electrodes 3 and 3 are collectively formed in a predetermined region on the surface of the groove 16. By removing the mask 17, a total of 36 elements 18 corresponding to coil components are produced on the base material 13.

  Further, as shown in FIG. 7B, the base material 13 is inverted and placed on the dicing tape 14 so that the planned mounting surface 2a side of each core structure 2 faces downward. And the element 18 corresponding to a coil component is divided | segmented separately as shown in FIG.7 (c) by shaving the fixed surface 2b plan side of the base material 13 by dicing. Finally, when a plating layer is formed on the terminal electrodes 3 and 3 of each element 18 by barrel plating, for example, the coil component 1 shown in FIGS. 1 to 3 is completed. Alternatively, the coil component 1 shown in FIGS. 1 to 3 may be obtained by first performing plating in the state of the base material 13 and then dividing each element 18.

  In this coil component 1, the side surfaces 2 c and 2 c of the coil structure 2 are inclined, and the cross-sectional shape of the coil structure 2 is a trapezoidal shape that spreads from the mounting surface 2 a side to the opposing surface 2 b side. With such a configuration, in the coil component 1, as shown in FIG. 8, for example, when mounting on the circuit board 19, the solder fillet 20 is formed in the space T formed by the circuit board 19 and the side surfaces 2c and 2c. A margin can be provided. Thereby, in the coil component 1, it becomes possible to make a space | interval with the other electronic component (not shown) adjacent in the case of mounting, and can implement | achieve the improvement of integration efficiency.

  Further, as shown in FIG. 8, since the open angle θ formed between the circuit board 19 and the side surfaces 2c and 2c is an acute angle, a load on the solder fillet 20 is applied even when a stress such as bending is applied to the circuit board 19. It is possible to suppress the occurrence of defects such as cracks in the solder fillet 20. Furthermore, when the coil component 1 is arranged on the circuit board 19 as compared with the case where the cross-sectional shape of the core structure 2 is narrowed from the mounting surface 2a side to the facing surface 2b side, The number of vertices visually recognized at can be reduced. For this reason, it becomes possible to improve a worker's visibility.

  In the coil component 1, the terminal electrodes 3 and 3 are formed along the side surface 2 c where the air gap S faces from the boundary portion between the mounting surface 2 a and the side surface 2 c to the boundary portion between the side surface 2 c and the facing surface 2 b. The electrode portion 3a and the electrode portion 3b formed on the edge of the mounting surface 2a continuously to the electrode portion 3a. For this reason, since the area of the terminal electrodes 3 and 3 can be sufficiently secured, the solder adhesion strength can be sufficiently secured when mounted on the circuit board 19.

  Furthermore, the electrode portion 3a is formed away from the boundary line L1 between the side surface 2c and the other side surface 2d, and the electrode portion 3b is formed away from the boundary line L2 between the mounting surface 2a and the other side surface 2d. ing. Thereby, for example, a phenomenon (film blur) in which the film of the electrode portions 3a and 3b formed by sputtering wraps around the other surface of the core structure 2 can be suppressed. By suppressing film blurring, unnecessary growth of the plating layer can be suppressed in the step of forming the plating layer after the terminal electrodes 3 and 3 are formed.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the pair of terminal electrodes 3 and 3 are formed on the side surfaces 2c and 2c, but two or more pairs of terminal electrodes 3 and 3 may be formed. That is, as shown in FIG. 9, the terminal electrodes 3 may be formed on each of the side surfaces 2c and 2c and the other side surfaces 2d and 2d to form two pairs of terminal electrodes 3 and 3. As shown in FIG. Three terminal electrodes 3 spaced apart from each other may be formed on each of 2c and 2c and the other side surfaces 2d and 2d, and six pairs of terminal electrodes 3 and 3 may be formed. In such a case, even if the coil component 1 is expanded to a multi-terminal product, the above-described effects can be exhibited.

  Moreover, a pair of side surfaces having an inclination as described above may be used. In this case, as shown in FIG. 11, only the substantially central part of the side surfaces 30c, 30c facing each other in the core structure 30 may be inclined, and the terminal electrode 31 may be formed on this inclined part, as shown in FIG. In addition, the entire side surfaces 40c and 40c facing each other in the core structure 40 may be inclined, and the terminal electrode 41 may be formed so as to cover the entire surface of the inclined portion. Although not shown, for example, the planar shape of the core structure may be a polygonal shape such as a regular hexagon, and each side surface of the core structure may be selectively inclined.

  The present invention can also be applied to other surface-mounted electronic components such as chip capacitors, chip varistors, chip inductors, and chip beads.

It is a perspective view of the coil component shown as one Embodiment of the surface mount type electronic component which concerns on this invention. It is a side view of a coil component. It is the figure which looked at coil components from the mounting surface side. It is a perspective view which shows the state which removed the terminal electrode from the coil components shown in FIG. It is a top view of a coil substrate. It is a figure which shows the manufacturing process of the coil components shown in FIG. FIG. 8 is a diagram showing a manufacturing process subsequent to FIG. 7. It is a figure which shows the state which mounted the coil components on the circuit board. It is the figure which looked at the coil components which concern on a modification from the mounting surface side. It is the figure which looked at the coil components which concern on another modification from the mounting surface side. It is the figure which looked at the coil components which concern on another modification from the mounting surface side. It is the figure which looked at the coil components which concern on another modification from the mounting surface side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Coil components (surface mount type electronic component), 2, 30, 40 ... Core structure (element body), 2a ... Mounting surface, 2b ... Opposing surface, 2c, 30c, 40c ... Side surface, 2d ... Other side surface, 3, 31, 41 ... terminal electrodes, 3a ... electrode portions formed on side surfaces, 3b ... electrode portions formed on mounting surface, L1 ... boundary line between side surfaces and other side surfaces, L2 ... mounting surface and other side surfaces And the border.

Claims (6)

A surface-mount type electronic component comprising a mounting surface, an opposing surface facing the mounting surface, an element body having a side surface intersecting the mounting surface and the opposing surface, and a terminal electrode provided on the element body Because
The side surface is inclined such that a cross-sectional shape of the element body is widened from the mounting surface side toward the opposing surface side,
The surface mount type electronic component according to claim 1, wherein the terminal electrode has an electrode portion formed on the side surface. And further comprising another side surface adjacent to the side surface and intersecting the mounting surface and the facing surface,
The surface-mount type electronic component according to claim 1, wherein the electrode portion is formed apart from a boundary line between the side surface and the other side surface.   The surface-mount type electronic component according to claim 1, wherein a cross-sectional shape of the element body is a trapezoid.   The surface-mounted electronic component according to claim 1, wherein the terminal electrode further includes an electrode portion that is continuous with the electrode portion and formed on the mounting surface.   The surface-mount type electronic component according to claim 4, wherein the electrode portion formed on the mounting surface is formed apart from a boundary line between the mounting surface and the other side surface.   The surface-mount type electronic component according to any one of claims 1 to 5, wherein two or more pairs of the side surfaces are formed.

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