JPH0547590A - Laminated electronic component - Google Patents

Abstract

PURPOSE:To provide a laminated electronic component possessed of a direction discriminating function of very high reliability. CONSTITUTION:Ceramic layers 20, 30, 40, and 50 where electrodes are formed as the component parts of an electronic component are laminated into one piece for the formation of a laminated electronic component, where ceramic layer 60 where a direction discriminating pattern of metal film is formed is inserted under the ceramic outermost layer 7.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a laminated LC filter, etc.
The present invention relates to a laminated electronic component formed by laminating ceramic layers, and particularly to a laminated electronic component having a function of identifying the directionality of the component body.

[0002]

2. Description of the Related Art For example, a laminated LC as a laminated electronic component
The filter has a completely monolithic structure by integrally firing a capacitor in which ceramic dielectric sheets having capacitance electrodes are laminated and an inductor in which ceramic dielectric sheets having electrode films or print coils are laminated. This is an LC circuit, but sometimes the components have directionality.

By the way, the above-mentioned laminated electronic components such as the laminated LC filter are often used as surface-mounted components in a printed circuit board. Therefore, the appearance shape is almost standardized, and the shape is a small chip-like substantially rectangular parallelepiped shape. Further, an internal electrode is formed inside the chip, and an external electrode that serves as a lead-out terminal of the internal electrode to the outside is formed on an outer surface portion of the chip.

When mounting a laminated electronic component having such an external shape at a predetermined position on a printed circuit board, its directionality must not be mistaken, and each external electrode must be accurately mounted at a predetermined position. .. The directionality of a laminated electronic component means specifying the three-dimensional direction of the component, that is, the front, back, left, right, and top and bottom directions, and when mounting the laminated electronic component, the directionality is clearly identified. It is necessary to do so. Therefore, in the related art, a method of stamping (or printing) a direction identification mark with black ink on a part of the surface of the formed laminated electronic component is often adopted.

[0005]

However, according to the above-mentioned method for stamping the direction identification mark, an extra step for stamping the direction identification mark is required in addition to the manufacturing process of the laminated electronic component. This complicates the process and inevitably leads to higher costs.

[0006] Further, since it is a method of applying ink,
I can not avoid the bulge of the application part,
This has resulted in the loss of surface smoothness in laminated electronic components. This leads to loss of the self-alignment effect at the time of soldering, and thus there is a large possibility of soldering failure. As one method of solving such a problem, a technique of simultaneously firing a direction identification mark inside the laminated electronic component at the stage of firing the laminated electronic component is disclosed in Japanese Patent Publication No. 3-856.
9 are disclosed. According to this technique, there is no need to provide a separate step for applying the direction identification mark, and the direction identification mark is formed inside the laminated electronic component, so that there is no problem with the surface smoothness of the laminated electronic component. Further, since it is fired and integrated with the laminated electronic component, its reliability as a mark function becomes extremely high.

However, in this technique, a mark made of a white dielectric material is formed on the printed board as a direction identification mark, and a Ba to brown-dark brown color is present on the upper part of the mark.
Since the laminated dielectric layer of TiO ₃ is provided, the contrast effect of the color tone between the two is used to aim at the mark identification effect. However, when the layer thickness of the laminated dielectric layer is increased, the contrast There is a high possibility that the direction identification effect will be reduced and the direction identification effect will be reduced.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a laminated electronic component having an extremely reliable direction identifying function.

[0009]

According to the present invention, a direction identification pattern is formed of a metal film inside a ceramic outermost layer in a laminated electronic component in which ceramic layers having electrodes of component elements are laminated and integrated. It is characterized in that a ceramic layer is inserted.

[0010]

According to the above structure, a laminated electronic component is formed by integrally laminating ceramic layers having electrodes as component elements. Further, inside the ceramic outermost layer of this laminated electronic component, a ceramic layer having a direction identification pattern for identifying the front / back, left / right and up / down directions of the laminated electronic component formed by a metal film is inserted.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 1 is an exploded perspective view showing a structure of a laminated LC filter 1 which is one of laminated electronic components according to the present invention. The laminated LC filter 1 has a predetermined thickness 6
Two ceramic dielectric layers 2 to 7 and various electrode patterns 20, 30, 40, 50, 60 inserted between the respective layers
(The portion shown by hatching in the drawing). In the drawings, any of the electrode patterns 20-60
Although both are drawn in the same square shape, the shape is actually different depending on the function as a circuit element. For example, the shield pattern 20 is formed on the upper surface portion of the lower ceramic outermost layer, and the coil pattern 30 is further stacked on the upper surface portion of the ceramic dielectric layer 3 laminated on the upper portion thereof. The capacitor pattern 40 is formed on the upper surface of the ceramic dielectric layer 4, and the shield pattern 50 is formed on the upper surface of the ceramic dielectric layer 5 which is further laminated thereon, and the ceramic dielectric layer 6 which is further laminated thereon. Direction identification patterns 60 are formed on the upper surface of each. Further, in the drawing, each ceramic dielectric layer 2 to 7 is shown in a block diagram.

In the laminated LC filter 1 having the above structure, the coil pattern 30 and the capacitor pattern 40 form a filter circuit using an LC resonance circuit. Also, regarding the shield patterns 20 and 50,
It is provided to protect such a filter circuit from an external electromagnetic field. Further, the direction identification pattern 60 is peculiar to the laminated electronic component according to the present invention, and the direction (front and back, left and right, up and down direction) of the laminated electronic component (usually, its appearance is formed in a rectangular parallelepiped shape). It is provided to identify that. Note that this direction identification pattern is necessary for mounting the laminated LC filter 1 at a predetermined position on a circuit board (not shown) without confusing the directionality thereof.

On the other hand, each electrode is formed inside the laminated electronic component by the coil pattern 30 and the capacitor pattern 40 (this is referred to as an internal electrode), and these internal electrodes serve as lead-out terminals to the outside of the laminated electronic component. External electrodes (not shown) are formed on the outer surface portion. Then, in the completed laminated LC filter 1, a so-called filter function is executed with respect to the current input through the external electrode.

FIG. 2 is a top view showing a typical example of the direction identification pattern formed on the ceramic dielectric sheet 10.
Each of the patterns (a) to (d) has a configuration in which the direction identification marks 11 to 15 (portions shown by hatching) are formed on a part of the surface of the ceramic dielectric sheet 10.
(A) is an upper left directional pattern, (b) is an upper right directional pattern, (c) is a lower right upper left directional pattern, (d)
Indicate the upward central patterns, respectively.

By forming such direction identification marks 11 to 15 on the surface of the ceramic dielectric sheet 10, the directionality of the laminated electronic component can be identified at a glance. Further, regarding the shape of the mark, a quadrangle is used in the embodiment, but of course, the shape is not limited to this, and a mark having a triangular shape or the like may be used.

Next, the laminated LC filter 1 having the above structure
The processing flow of will be described. The outline of this processing flow is that after printing each electrode pattern on each ceramic dielectric sheet, and then stacking this printed sheet and a dummy sheet (which is an unprinted ceramic dielectric sheet) with a predetermined thickness Then, heat press bonding is performed to obtain a laminated semi-finished product.
Subsequently, this laminated semi-finished product is cut into chips and fired, and external electrodes are attached to the outer surface portions thereof to form an integrated laminated electronic component.

The optimum method for inserting the direction identification pattern 60 in the above basic manufacturing flow is as follows. That is, like the other electrode patterns, the direction identification pattern is printed as a metal film for forming electrodes on the surface of the ceramic dielectric sheet, and this sheet is laminated together with other sheets as one lamination component. Also, a white type is used as the ceramic dielectric sheet for printing, and a black paste is used for printing the direction identification pattern 60. By doing so, the contrast of the color tone of the direction identification pattern with respect to the ceramic dielectric sheet becomes large, so that the identification of such pattern becomes extremely easy.

On the other hand, regarding the insertion position of the direction identification pattern 60, in consideration of the easiness of identification from the surface of the component, the laminated L
The direction identification pattern 60 is provided inside the ceramic dielectric layer 7 (see FIG. 1) which is the outermost layer of the C filter 1 and covers at least 20 to 100 μm from the chip surface.
Adjust so that is located. Further, the direction identification pattern 6
Regarding the material for forming 0, it is necessary to have the same thermal characteristics as those of the metal films forming the other electrodes when firing, and a material that does not affect the electrical characteristics of the laminated LC filter 1 at all. It is necessary to be. Therefore, in the present invention, the same metal film material as the metal film forming the other electrodes is used, and the above conditions as the material for forming the direction identification pattern 60 are successfully satisfied.

[0019]

As described above, according to the present invention, in a laminated electronic component such as a laminated LC filter, a laminated inductor, a laminated capacitor or the like, a direction identification pattern is inserted inside the outermost ceramic layer, so that The pattern can be easily identified. Further, since the pattern is formed by firing inside the laminated electronic component, the reliability as an identification mark is extremely high. Furthermore, when the pattern is formed of the same metal film material as that of the other internal electrodes, there is no problem in stacking and integration, and there is no influence on the electrical characteristics of the stacked electronic component. Therefore, by using the laminated electronic component according to the present invention, it is possible to surely mount the laminated electronic component at a predetermined position on the printed circuit board without mistaking its directionality.

Further, unlike the prior art, it is not necessary to separately provide a process for attaching the direction identification pattern, so that the manufacturing cost of the laminated electronic component can be reduced. Further, since the surface smoothness of the laminated electronic component is not impaired, there is also a secondary effect that it does not cause any trouble in soldering at the time of mounting.

[Brief description of drawings]

FIG. 1 is a laminated L which is one of laminated electronic components according to the present invention.
It is an exploded perspective view showing composition of a C filter.

FIG. 2 is a top view showing a typical example of a direction identification pattern formed on a ceramic dielectric sheet.

[Description of Reference Signs] 1 laminated LC filter 2 to 7 ceramic dielectric layer 20, 50 shield pattern 30 coil pattern 40 capacitor pattern 60 direction identification pattern

Claims (1)

[Claims] 1. A laminated electronic component in which ceramic layers having electrodes of component elements are laminated and integrated, and a ceramic layer having a direction identification pattern formed of a metal film is inserted inside a ceramic outermost layer. A laminated electronic component characterized by.