JPS59191203A - Dielectric porcelain material - Google Patents

Abstract

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

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a capacitor portion of an LC composite chip element, which is made of a low-temperature sintered dielectric ceramic material having a high Q, and is composed of 9% bulk sintered material. The present invention relates to a low-temperature sintered dielectric ceramic material suitable for use as a low-temperature sintered dielectric ceramic material.

[Prior art]

Conventionally, LC composite devices are constructed from a combination of separately manufactured coils and capacitors and are widely used, for example, as filters.

By the way, an LC composite element is generally used in which a capacitor and a wire-wound coil are appropriately combined, resin-molded, and lead wires are attached. However, this resin mold type is quite large and cannot accommodate the recent thinner and more portable electronic devices.

Therefore, as a corresponding item, the L of the lead dress and the
C composite chips are available.

By the way, this type of conventional LC composite chip component...

As shown in FIG. 1, a dielectric layer 1 is formed by printing a paste of dielectric powder such as TiOz or BaTiOs on a suitable removable substrate (not shown) by a printing method.

On top of that, a paste of metal powder such as Ag, Ag-Pd, Pd, etc. is printed on this dielectric layer 1 by a printing method to form an electrode 2, and then a dielectric layer 3 is printed on it. (shown exploded for clarity), another electrode 4 is formed on this dielectric layer 3. Then, on this electrode 4, an intermediate layer 5 made of a paste of glass powder or a 7-elite-dielectric powder mixture is printed, and on top of that, a magnetic layer 6 made of a paste of permeable magnetic ferrite powder is printed, and then the above-mentioned A coil-forming conductor 7 is printed using a powder paste similar to the metal powder described above, a magnetic layer 8 that masks a part of the conductor 7 is printed, and a conductor 9 to be connected to the conductor 7 is printed. Similarly, the magnetic layer 10. Conductor 11. Magnetic layer 12. Conductor 13. A magnetic layer 14 and a conductor 15 are printed, and finally a magnetic layer 16 is laminated.

The thus obtained laminate is fired at high temperature to convert it into an integral sintered body, and as shown in Fig. 2, appropriate external terminals (silver paste, etc.) 17°18 are baked on the exposed conductor ends at both ends. L.C.
Complete composite chip parts.

At this time, the equivalent circuit becomes as shown in FIG.

By the way, in the above case, the existence of the intermediate layer 5 is due to the following reason. That is, the dielectric layers 1 and 3 constituting the laminated body for a capacitor are composed of Ti02 and BaT103, and the magnetic layers 6 and 3 constituting the laminated body for a coil are composed of Ti02 and BaT103.
8. . . . etc. are composed of permeable magnetic 7E2ite, and therefore these dielectric layers and magnetic layers have different coefficients of thermal expansion. Therefore, if these dielectric layers and magnetic layers are simply laminated as they are, the shrinkage rates will be different during cooling after sintering, which will likely cause cracks and warpage, resulting in defective parts. Therefore, it was necessary to interpose an intermediate layer 5 having a coefficient of thermal expansion intermediate between these.

Instead of such a one-piece type, the dielectric and electrodes constituting the capacitor are laminated by sheet method, printing method, etc.
Sintering and laminating the magnetic material and electrodes that make up the inductor are performed separately, and each laminated chip is fired at a predetermined temperature to form a chip capacitor and a chip inductor, respectively, and these are bonded one by one to form an LC. They were creating a composite chip. However, in this method, the method of bonding the chip sintered body has the drawback that the manufacturing process is complicated because the chip sintered body is minute, and mass production cannot be easily carried out.

[Problem that the invention seeks to solve]

In this way, batch-fired LC composite chip parts have the problem of requiring an intermediate layer to absorb the difference in thermal expansion coefficient between the dielectric material in the capacitor part and the magnetic ferrite part in the inductor part. However, there is a problem in that a complicated process is required in which minute chips must be bonded using an intermediate adhesive layer that is sintered separately.

[Means for solving problems]

In order to improve this problem, the inventors of the present invention have developed a structure in which the coefficient of thermal expansion is between 90 and 100 x 10''/'C when fired together with magnetic ferrite. There is no difference.

As a result of searching for a material with sufficient adhesive strength for this purpose, it was found that a sintered body consisting mainly of Tie2 of CuO or a mixture of CuO and Mn oxide would achieve the desired purpose.

Moreover, it was found that the material of the present invention satisfies all electrical properties and can be sintered at a relatively low temperature (has a sintering temperature and shrinkage rate comparable to that of magnetic ferrite).

Therefore, it is possible to manufacture an LC composite chip by laminating and firing the KLC integrated before firing, so there is no need to glue sintered bodies one by one as in the past, and mass production is easy. This has the advantage that the amount of material consumed can be reduced since no intermediate layer or intermediate adhesive layer is required, and manufacturing costs can be reduced.

〔Example〕

Next, the present invention will be explained in detail.

Example 1 Commercially available titanium oxide, oxidized steel, and manganese carbonate.

'rio, 9s, o mol%, Cu05.0 mol%, MnC010,757wt% were weighed to give a weight of 100g.

Add 200g of pure water and 120g of agate stone to this.

The mixture was placed in a ball mill and mixed for 16 hours, followed by dehydration and drying. Then, 50g of dry powder, 16g of ethylcellulose 8-ti solution (solvent: terpineol) as a binder, and 25g of terpineol as a solvent were weighed out, stirred for 3 hours in a Raikai machine, and processed with three rolls to form a paste.

This paste and the paste of Ag powder were alternately laminated by screen printing to make a chip capacitor. After drying,
Cut the sintered body into chips with dimensions of 4.5 x 3.2 m, and
A chip capacitor was obtained by sintering in air at °C for 2 hours. The various properties obtained were as shown in Table 1.

Here, α is the coefficient of thermal expansion, and sh is the shrinkage rate, which indicates the shrinkage state after firing based on the dimensions before firing.

IR is insulation resistance, v is breakdown voltage, and shows the case where the distance is 50 μm.

Example 2 A chip capacitor was manufactured in the same manner as in Example 1, except that the blending ratio of titanium oxide and oxidized steel was changed.

Its properties are shown in Table 2.

Table 2 (margin) The above characteristics are all satisfied as a capacitor part of an LC composite chip component.

Example 3 Ni and Cu obtained by firing in air at a firing temperature of 860°C.

Zn ferrite has the characteristics /i=109,Q(
4MHz)=56, 5h=16.5%, α=94X1
[Magnetic ferrite having a temperature of 1-10°C is laminated with a number of turns of 10T8, and the dielectric material of Example 1 is laminated thereon, and L
A C composite chip component was prepared and fired in air at 860° C. for 2 hours to obtain a sintered body of an LC composite chip component. The frequency characteristics of the attenuation amount are shown in FIG. This chip has a resonant frequency of 5.936 MHz and an attenuation of 25.35 dB, which is sufficient for practical use.

〔effect〕

According to the present invention, it is possible to provide a dielectric material that has approximately the same coefficient of thermal expansion as magnetic ferrite and can be fired at the same temperature. can be fired in bulk.As a result,
Very small LC composite chip parts can be efficiently produced.

[Brief explanation of the drawing]

1 to 3 are explanatory diagrams of a conventional LC composite chip component requiring an intermediate layer, and FIG. 4 is a characteristic diagram of a composite chip component according to an embodiment of the present invention. 1.3 Dielectric layer 2.4 Electrode 5 Intermediate layer

Claims (1)

[Claims] (11T loz (50-99-9%/”ly
) t cuo (0.1 to 50 mol%) dielectric ceramic material for ceramic capacitors. (2) The dielectric ceramic material according to claim (1), wherein up to 5.0 w% of Mn'IcMnC0 is added to the dielectric.