JPH07106144A - Surface mounting type electron part and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a surface mounting type electronic part on which solderability can be inspected in a simple manner constituting no hindrance in the insulating property on the surface of a substrate, and also to provide the method of manufacture with which an external electrode can be formed on the side face of a substrate. CONSTITUTION:A U-shaped groove part 11 is formed on the bottom face of a mother substrate 10, and an external electrode 6 is formed on the groove part 11 and its circumference using a thick film method or a thin film method. Subsequently, the mother substrate 10 is cut for every one-unit constituent element by cutting wires 12 and 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount type electronic component of an inductance or a capacitor or a composite type of these, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, various surface mount electronic components have been provided in which a plurality of external electrodes are provided on the surface of a substrate in which circuit elements are encapsulated, or a substrate which itself has a circuit element function (for example, dielectric). ing. The method of forming the external electrodes of this type of electronic component is roughly classified into a method of forming the external electrodes at the stage of the mother substrate and a method of forming the external electrodes at a stage of cutting out one unit from the mother substrate. The method of forming the external electrodes at the stage of the mother substrate is efficient and preferable because the external electrodes can be collectively formed on the substrate and the handling is easy. However, the external electrode formed by this method is not formed on the side surface (cut surface) of the substrate after being cut out one by one, but is formed only on the bottom surface.

On the other hand, when this type of electronic component is surface-mounted on a printed circuit board, a solder fillet is used to visually inspect whether or not soldering is reliably performed (good or bad solderability). Need to be formed on the side surface of the substrate. However, in the electronic component manufactured by the method of forming the external electrodes at the stage of the mother substrate as described above, the external electrodes are not formed on the side surfaces, so that the solderability test is extremely difficult. On the other hand, it may not be preferable that the external electrode is provided on the entire side surface of the substrate, particularly up to the upper edge portion. This is because, for example, when providing some kind of circuit conductor on the upper surface of the substrate, there arises a problem in insulation.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to make it easy to inspect the solderability at the time of mounting on a printed circuit board and to prevent the insulation of the upper surface of the board from being hindered. It is to provide a mountable electronic component. Another object of the present invention is to provide a method for manufacturing a surface-mounted electronic component, which enables external electrodes to be formed on the side surface of a substrate cut out in one unit at the stage of a mother substrate.

In order to achieve the above object, an electronic component according to the present invention is a surface mount type electronic component in which a plurality of external electrodes are provided on the surface of a substrate enclosing a circuit element or a substrate having a circuit element function. The external electrode is provided from the bottom surface of the substrate to the side surface, and does not reach the upper edge portion of the side surface. In the above electronic component, since the external electrodes are provided from the bottom surface to the side surface of the board, the solder adheres to the side surface portion of the board during mounting on the printed board to form a so-called solder fillet. The solderability can be easily inspected by distinguishing the presence or absence of the fillet. Moreover, since the external electrode does not reach the upper edge of the substrate, it has good insulation properties from the upper surface of the substrate. For example, even when some circuit conductor is provided on the upper surface of the substrate, the conductor and the external electrode are not connected to each other. Does not impair the insulation properties of.

Further, in the manufacturing method according to the present invention, a mother substrate is manufactured, a groove portion is formed on the bottom surface of the mother substrate, an external electrode is provided in the groove portion, and then the mother substrate is cut into each unit of constituent elements. To do. The external electrodes are formed in or around the groove by a thick film method by printing or baking a conductive paste, or a thin film method such as vapor deposition or sputtering. In the electronic component cut out from the mother substrate in units of one, the external electrodes are also formed in the groove portion, that is, the side surface portion of the substrate.

[0007]

Embodiments of an electronic component and a manufacturing method thereof according to the present invention will be described below with reference to the accompanying drawings. 1 and 2 show a surface mount type inductor as a first embodiment. This inductor has recesses 5 and 5 on both lower sides of the substrate 1.
The external electrodes 6 and 6 are formed from the bottom surface of the substrate 1 to the recesses 5 and 5.

As shown in FIG. 2, the substrate 1 is formed by stacking a lower layer portion 1b similar to the upper layer portion 1a which is a laminated body of ceramic sheets, and a coil conductor 2 functioning as an inductance is provided on the lower layer portion 1b. Is provided. Both ends of the coil conductor 2 are extended to both side surfaces of the substrate 1 and electrically connected to the external electrodes 6 and 6. Next, a method for manufacturing this inductor will be described with reference to FIG.

First, the mother substrate 10 is manufactured. The mother board 10 is manufactured by forming one unit of constituent elements of an inductor in a planar continuous manner in the vertical and horizontal directions. That is, the coil conductor 2 is formed for each unit on the wide lower layer portion 1b,
A wide upper layer portion 1a is overlaid thereon and integrally fired. Next, a U-shaped groove 11 is formed on the bottom surface of the mother substrate 10 [see FIG. 3 (A)]. The groove 10 becomes the recesses 5 and 5 when cut in a later step.

Next, the external electrodes 6 are formed on the groove 11 and its periphery.
6 is formed [see FIG. 3 (B)]. The external electrodes 6 and 6 are formed by a thick film method such as printing and baking a conductive paste, or a thin film method such as vapor deposition or sputtering, by masking unnecessary portions. Next, the mother substrate 10 is cut out for each unit of component [see FIG. 3 (C)], and the inductor shown in FIG. 1 is obtained. The cutting is performed by a cut line 12 in the vertical direction and a cut line 13 in the center of the groove portion 11 in the horizontal direction. In FIG. 3, only two units of the mother substrate 10 are shown in the horizontal direction, but in reality, a plurality of units are used as one mother substrate.

FIG. 4 shows an oscillator in which the piezoelectric element 3 is enclosed in the substrate 1. The configuration and manufacturing process of the external electrodes 6 and 6 of this oscillator are the same as those described with reference to FIGS. In each of the electronic components shown in FIGS. 1 and 4, external electrodes 6 and 6 are formed on the side surface of the board 1, and when mounted on a printed circuit board (not shown), solder is applied to the side surface portion. A fillet is formed by adhesion, and solderability can be easily inspected. The external electrodes 6 and 6 are formed only on the lower half of the side surface, and have a creeping distance required for insulation with the upper surface of the substrate 1. Therefore, even when the circuit conductor is provided on the upper surface of the substrate 1, the insulating property between the circuit conductor and the external electrodes 6 and 6 can be secured, and the upper surface can be widely used.

By the way, the types of electronic parts according to the present invention are not limited to the above-mentioned inductors and oscillators, but widely extend to capacitors and composite parts thereof. Further, the substrate 1 itself is not only used for enclosing the circuit element, but also has a circuit element function (for example,
It may have a dielectric property).

FIG. 5 shows another type of electronic component, in which three groove portions 11 are formed on the bottom surface of the substrate 1 for each unit of component at the stage of the mother substrate, and the external electrodes 6 are formed in the groove portions 11. Is provided. The manufacturing process is the same as that of FIG. 3, but the position of the cut line 13 in the lateral direction and the position of the groove 11 with respect to the cut-out substrate 1 are different. Although the inside is not shown, it is configured as a composite component of an inductance and a capacitor, for example.

FIG. 6 shows various shapes of groove portions, the shapes of the external electrodes 6 formed in the groove portions, and the cut shape of the side surface of the substrate 1. In FIG. 6A, a V-shaped groove is formed on the bottom surface of the substrate 1, and the external electrode 6 is formed from the bottom surface to the inclined surface. In FIG. 6B, a V-shaped groove portion wider than that in FIG. 6A is formed, and the external electrode 6 is formed on the inclined surface. Figure 6
In (C), the upper surface side of the substrate 1 is also cut into a V shape. In FIG. 6D, a rectangular groove portion is formed, the external electrode 6 is formed on the vertical surface thereof, and the upper surface side is cut into a V shape. In FIG. 6E, a rectangular groove is formed, the external electrode 6 is formed from the bottom surface of the substrate 1 to the vertical surface, and the upper surface side is also cut into a rectangle.

According to the manufacturing method described above, since the external electrode 6 is formed on the mother substrate 10, it is simpler than the method in which the substrate 1 is cut out for each unit and then formed.
Suitable for mass production. Moreover, since the groove portion is formed in the mother substrate and the external electrode is formed in this groove portion, the external electrode is located on the side surface of the substrate cut out for each unit. In addition, the external electrode thus formed does not reach the upper edge portion of the substrate, and has good insulation with the upper surface of the substrate. Although the mother substrate 10 in the above embodiment is shown as a monolithic substrate, it may be formed of an aggregate obtained by joining electronic components.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment (inductor) of an electronic component according to the present invention.

FIG. 2 is a perspective view in which a part of the electronic component shown in FIG. 1 is cut away.

FIG. 3 is a perspective view showing a manufacturing process of the electronic component shown in FIG.

FIG. 4 is another embodiment (oscillator) of the electronic component according to the present invention.
Is a perspective view showing a part of which is cut away.

FIG. 5 is a perspective view showing another embodiment (LC composite component) of the electronic component according to the present invention.

FIG. 6 is a partial front view showing various external electrode configurations and cut shapes of electronic components manufactured by the manufacturing method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate 5 ... Recessed part (groove part) 6 ... External electrode 10 ... Mother substrate 11 ... Groove part

Claims (2)

[Claims] 1. A surface-mounted electronic component in which a plurality of external electrodes are provided on a surface of a substrate enclosing a circuit element or a substrate having a circuit element function, wherein the external electrode extends from a bottom surface of the substrate to a side surface and a side surface. The surface mount type electronic component is characterized in that it is provided without reaching the upper edge of the. 2. A method of manufacturing a surface mount electronic component, wherein a plurality of external electrodes are provided on the surface of a substrate enclosing a circuit element or a substrate having a circuit element function, wherein a component of one unit of the electronic component is its longitudinal and lateral directions. A step of manufacturing a mother substrate in a planarly continuous state, a step of forming a groove on the bottom surface of the mother substrate, a step of providing an external electrode in the groove, and a step of forming the mother substrate for each unit of one unit. A method of manufacturing a surface mount electronic component, comprising: a cutting step.