JPS6376313A - Laminated lc filter component - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to laminated LC filter components. More specifically, the present invention relates to a laminated LC filter component that is equipped with a filter circuit network, has fewer defects, and has good mechanical properties.

[Prior art and its problems]

Filter circuits have a wide range of applications in electronic circuits. For example, a filter circuit as shown in FIG. 1 (1m) has a frequency-attenuation characteristic as shown in FIG. 1(b).

As can be seen from figure (a), such a filter circuit requires multiple combinations of many capacitors and inductors, so it is easy to connect individual circuit elements to realize a sophisticated filter circuit. Not.

One known method for dealing with this problem is to manufacture filter components by lamination or vapor deposition. However, a method of simultaneously realizing a large number of circuit patterns through a unified and reasonable manufacturing process has not been successfully achieved except for those with a small number of elements. In particular, no good method has been devised for the coil or inductor portion of the filter component. Furthermore, when combining the parts of the multilayer composite capacitor and the part of the multilayer composite coil by weight, the affinity between the dielectric of the former and the magnetism of the latter is low, and there is a difference between them due to heat shrinkage during firing. There is a difference in the coefficient of expansion and expansion, which causes problems such as cracks and distortion in the fired crystal.

[Purpose of the invention]

It is an object of the present invention to provide a laminated LCy filter component with a simplified manufacturing process, fewer defective products, and good mechanical properties.

[Summary of the Invention] The laminated filter component of the present invention includes a laminated capacitor part and a laminated coil part, each of which contains a plurality of capacitors and a plurality of coils, and in which the lead-out portions of these capacitors and coils are exposed on the periphery. , an intermediate material layer having sintering characteristics between the dielectric layer and the magnetic layer facing each other is interposed between the sintered body, which is weighted together, and the fill and capacitor through its circumferential surface, which is necessary for the LC filter. The lead-out portion is configured to have a predetermined external terminal provided on the lead-out portion and to connect these portions so as to perform a proper wire connection.

A major advantage of the present invention is that the use of an intermediate material layer suppresses the occurrence of defects due to cracks, warpage, and distortion in laminated C filter components, and provides a product of high quality. Further, in the present invention, coupling between LC elements is performed by external terminals, and a complex filter can be easily realized. Further, the present invention has the advantage that the laminated coil portion can be laminated with about half a turn of conductive tm and magnetic layers in a reasonable manner to realize a plurality of coils at the same time.

[Detailed description of the invention]

FIG. 2 shows an example of a method for realizing the laminated LC filter circuit of FIG. 1 (&) consisting of four coils and nine capacitors. However, the method described here, especially IPf1
Special f in the coil part! The four-layer process provides a filter circuit with a larger number of coils and capacitors.
! I-layer LC filter components can also be manufactured easily.

Note that the lamination is performed by a well-known printing method, and the dielectric layer is made of B.
m T i O s T i O! Base 1 capacitor electrodes and coil conductor layers made of dielectric powder such as A
.

- It is formed by screen printing or the like using a metal powder paste such as P as A g.

The intermediate material layer is similarly formed by printing from paste. The intermediate material has properties intermediate between the magnetic layer and the dielectric layer, which not only prevents cracking and warping due to firing shrinkage, but also prevents cracking and warping due to firing shrinkage. ) and a barrier that suppresses characteristic deterioration due to diffusion of Nl, Cm, etc. between the dielectric layers. Non-magnetic Cu-based ferrites and materials containing Nl, such as CuSNl, pose problems in their diffusion.Therefore, it is necessary to design an intermediate material layer that improves all of these aspects. Preferred intermediate materials are Cu--Zn-based 7-elite powder and TlOs powder, and especially when the former is used on the magnetic ferrite side and T S OH on the dielectric side, excellent effects can be obtained.

(1) to (15) in FIG. 2 show the sequential manufacturing process of the laminated C filter component of the embodiment. Note that the diagram emphasizes the various patterns exposed on the top surface, and does not pay attention to the thickness, but it is approximately several to several + pm per layer.
I would like to be understood as such.

Steps (1) to (5) form a multilayer capacitor section.

In step (1), the ls electric body W11 is formed. Actually, it is formed on a substrate with good releasability (not shown). Thereon, in step (2), a capacitance forming electrode conductor 2 having a lead-out portion 3 to the periphery is formed. This pattern is such that a predetermined number of capacitors (nine in the example shown) can be formed. Next, in step (3), a dielectric layer 4 is formed on the entire surface, and then a capacitance forming electrode conductor layer 5 having a counter electrode is formed. Drawer part 6
is in the same position as the drawer part 3 (Fig. 1(a)
) in parallel to each coil (to make 4 capacitors) and in different positions (grounding example in Figure 1 (&) to make 5 capacitors connected to GND)
including. In step (5), a dielectric layer 7 is formed over the entire surface. In this way, the capacitor section 8 is obtained.

In step (6), an intermediate material M is applied to the entire surface of this capacitor section 8.
! Form J19.

Steps (7) to (20) show a method of forming a coil portion. In step (7), the magnetic layer 10 is applied to the entire surface of the intermediate material layer 19.
, and then in step (8), conductors 11 for four coil halves having lead-out portions 12 are formed. When the conductors 11 are arranged as shown in the figure, the thickness can be easily balanced, and a plurality of coils can be formed at the same time. In step (9), magnetic layers 1 are placed on both sides of the laminate.
3, and then in step (10) print the previous coil conductor 1.
1. Print approximately one turn of coil conductor 14 to be connected to 1.

Next, a magnetic material M15 is formed in the central portion. Magnetic layer 1
5.15 has some overlapping parts, but can generally form a uniform thickness throughout. Thereafter, in the same manner, the coil conductor 16 for about a hand turn, the magnetic layer 17, and the coil conductor 1B for about a hand turn are laminated, and the lead-out part 19 of the conductor 18 is locally placed at a different position from the lead-out part 12. (Step (11))
, (12), (13), (14)). Finally, in step 15, a magnetic layer is formed on the entire surface to complete the lamination.

By firing this laminate at a high temperature, a laminate consisting of a composite capacitor section 8, an intermediate material layer 9, and a composite fill section 21 is obtained as shown in FIG. If necessary, trimming conductor 2
1. Holes 22 and 23 (for inserting magnetic plugs, etc.) may be provided.

Finally, external terminal electrodes T1 to T12 are formed by baking a conductive paste. It will be apparent that these external terminals interconnect the coil and capacitor to realize the circuit of FIG.

Example 1 A sintered body with a three-layer structure using a non-magnetic z,-(uP intermediate material shown in Table 1 as the intermediate material layer, B a 710 g as the dielectric layer, and M+a-Zn ferrite as the magnetic layer) was made. The Cu distribution in the thickness direction was analyzed. Table 2 shows the results using a sample without an intermediate layer as a control. The sample without an intermediate layer cracked and warped. Compositions 1 to 4 did not have this problem.As can be seen from Table 2, copper that existed in the dielectric layer and magnetic layer generally diffuses to the interface.Also, when the C11 concentration in the intermediate material increases, the copper that existed near the interface The copper present in each layer increased in the dielectric layer, the magnetic material, and the magnetic material, and the same was true in the case where there was no intermediate material layer.
3, Cvs is smaller than in the case without intermediate material. Therefore, for compositions 1 to 4, the interface Cu is not much different from the case without the intermediate material layer.
Although it has a high concentration, it is significantly superior in terms of cracking and warping, and moreover, it can be seen that the impurity Ct1 does not diffuse into each layer. The results for Composition 4 show that there is no problem even if the intermediate layer contains a considerable amount of Cu.

Example 2 T on the 1g electric body side 10. Except for using non-magnetic Zn+Cu ferrite having the composition shown in Table 3 on the magnetic side,
A three-layer sintered body similar to 1 was made and analyzed.

The results are shown in Table 4 along with the control. It can be seen that diffusion to both sides can be ignored when the intermediate material layer is made of 2 mm.

[Effect]

As described above, in the present invention, a complicated LC circuit pattern can be easily realized by printing and sintering. Furthermore, by using intermediate materials, products with less distortion and fewer defects can be provided. The above-mentioned effects can be achieved, such as the ability to easily perform complex connections between the coil section and the capacitor section using peripheral external terminals.

In the above embodiment, one capacitor part and one fill part were used, but it will be clear to those skilled in the art that any number of capacitor parts and fill parts may be combined by interposing an intermediate material layer.

Table 1 (Unit is wt%) Table 2 Cu analysis value Table 3 Table 4 Cu analysis value

[Brief explanation of the drawing]

Figure 1(a) is a diagram showing the LC filter circuit, Figure 1(b)
) is a graph showing the same attenuation-frequency characteristics, Figure 2 (1) ~
(15) is a sequential process diagram for manufacturing a laminated LCy filter component according to an embodiment of the present invention, FIG. 3 is a perspective view of a component manufactured by the method shown in FIG. 2, and FIG. 4 is a laminated LC filter component of the present invention. This is a completed diagram. (0) (b) Figure 1 Figure 3 Figure 4

Claims (4)

[Claims] (1) A multilayer capacitor section that contains multiple capacitors and the lead-out portions of their electrodes are exposed on the periphery, and a multilayer inductor that contains multiple coils and the lead-out portions of each coil are exposed on the periphery. The coil is drawn out onto the circumferential surface of a sintered body in which the parts are superimposed with an intermediate material layer having sintering properties intermediate between the former surface dielectric layer and the latter surface magnetic layer interposed therebetween. A laminated LC filter component comprising an external terminal for mutually coupling a capacitor lead-out part, a capacitor lead-out part, and an external circuit so that a predetermined filter is constructed. (2) The filter connects one lead-out end of a predetermined capacitor to a common external grounding terminal, connects it to an external terminal that connects the coils in series, and connects the other lead-out end of these capacitors to a common grounding external terminal that connects the coils in series. The laminated LC filter according to item 1 above, which is connected to an external terminal. (3) The multilayer LC filter according to item 2 above, wherein the external terminal is formed such that a capacitor other than the predetermined capacitor is inserted between both ends of each coil. (4) The intermediate material layer is made of non-magnetic Cu-Zn ferrite, Ti
The laminated LC filter according to any one of items 1 to 3, comprising O_2 or a combination thereof.