JPS5860660A - Dielectric ceramic composition for high frequency - 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 The present invention relates to a dielectric ceramic composition for high frequency use.

In high frequency regions such as microwaves and millimeter waves, dielectric ceramics are widely used for dielectric resonators, dielectric substrates for MIC, and the like.

Conventionally, as this type of dielectric ceramic, ZrO2-8nO
, -TiOJ material, B az Ti@02 o
, (B a -S r )(Zr, Ti)03-based material,
Ba (Zn, Ta)0. Materials such as these are known.

These materials have a dielectric constant (gr) of 20 in the microwave band.
~40, Q is 4000~8000°, and the temperature coefficient (τf) of the resonance frequency is oppm, which is an excellent material with the characteristics of “c,” but recently, the frequency range used has become even higher, and it is compatible with this. Therefore, materials with even higher Q values are required.

Therefore, an object of the present invention is to provide a dielectric ceramic composition having a higher Q than the conventional one in a high frequency region.

That is, the gist of this invention is that the general formula Ba
(Nk, TayNb,)07/, -3x7. In the composition represented by 0.2≦X≦0.45.0≦y≦
0.67.0≦2≦0.67 (7: dashi, x+y+z=
It is characterized by being within the range of 1).

Hereinafter, this invention will be explained in detail according to examples.

High purity Bac'Os%Nip, Ta2O,, Nb2O
, to obtain porcelain having the composition shown in Table 1, and the weighed raw materials were wet mixed for 2 hours. Next, calcination was performed at 1200° C. for 2 hours, and a binder was added and wet-mixed again for 2 hours, followed by dehydration and sizing. The obtained powder was molded into a disk with dimensions of 12 Hayabusttx6wyzt at a pressure of 2000Kg/d, and
A porcelain sample was obtained by firing at 0°C for 4 hours.

The dielectric constant (4, Q) and temperature coefficient (Tf) of the resonant frequency were measured for the obtained ceramic sample at a frequency of 7 GHz, and the results are shown in Table 1. In Table 1, the * mark indicates the scope of this invention. everything else is within the scope of this invention.

Mar=lf; Figure 1 shows that among the compositions according to this invention, N
ip, Tag, 7. , NbO, /2N+' indicates the composition range. The numbers in the figure match the sample numbers in Table 1. The temperature coefficient (Tf) of the resonant frequency is +25°C to +85°C.
The value is calculated based on the following formula.

τi''-+τE-(1 Here, τE: Temperature change rate of dielectric constant (6) a=Linear expansion coefficient of porcelain sample As is clear from Table 1, according to the present invention,
In addition to showing a high list rate, f is also good, and in particular, a value of up to 9200 has been obtained for Q, making it useful for applications such as tsuba electric resonators and dielectric substrates for MIC in the high frequency region. Crocodile electric porcelain for high frequency use can be provided.

It should be noted that samples having compositions outside the scope of this invention (sample numbers 9 to 11) cannot be sintered and cannot be put to practical use.

[Brief explanation of drawings]

FIG. 1 shows Nip among the compositions according to the present invention. It is a ternary diagram showing the composition range of T a Os 72 , NbO5/. Patent applicant Murata Manufacturing Co., Ltd. (4)

Claims (1)

[Claims] General formula Ba (NixTayNbz)0,7. -1x7
．． In the composition represented by 0.2≦X≦0.45.
0≦y≦0.67.0≦2≦0.67 (However, x+
A dielectric ceramic composition for high frequency use, characterized in that the composition is in the range of y+z=i).