JPS6054901B2 - Dielectric ceramic composition for high frequency - Google Patents

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, ZrO has been used as this type of dielectric ceramic.

1Sn0. -TiO. Materials, mountains. Ti, O. . , (B
a,Br)(Zr,Ti)O. based materials, Ba(Zn, T
a) O. Materials such as these are known. These materials have a dielectric constant (E, ) of 20 to 40 and a Q of 40 in the microwave band.
00~8000) Temperature coefficient (Tf) of resonance frequency is 0p
Although it is an excellent material with characteristics of μm/° C., recently, the frequency range in which it is used has become even higher, and there is a corresponding demand for a material with an even higher Q value. Therefore, it is an object of the present invention to provide a dielectric ceramic composition that has a higher Q in the high frequency region than conventional compositions.

That is, the gist of this invention is that the general formula (B
a, -, Srv) (ZrxZnyTa2)O, 12-J
2-O,I.

In the composition represented by 0.02≦ri≦0.13,
0.02≦X≦0.13, 0.28≦y≦0.33, 0
．． It is characterized by being in the range of 59≦z≦0.65 (where x+y+z=1)6. Hereinafter, this invention will be explained in detail according to examples. High purity BaCO
3, srcoa, 2ro2, 2no, and Ta2O5 were weighed 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 heated to 2000 to 12 at a pressure of 9/c71f.
Molded into a disk from the dimensions of Tmφ×6Tfn, 1450
C. for 4 hours to obtain a porcelain sample. For the obtained porcelain sample, the dielectric constant E at a frequency of 7GH2,
Q) and the temperature coefficient Tf of the resonance frequency were measured, and the results are shown in Table 1. Items marked with * in Table 1 are outside the scope of this invention, and all others are within the scope of this invention. The temperature coefficient τf of the resonant frequency in Table I is a value determined in the temperature range of +25°C to +85°C based on the following equation.

Here, τε: Temperature change rate of dielectric constant ε α: Linear expansion coefficient of porcelain sample As is clear from Table 1, the present invention is as follows:
In addition to exhibiting a high dielectric constant, the γf is also good, and in particular, a maximum value of Q of 14,200 has been obtained, making it a high-frequency product useful for applications such as dielectric resonators and dielectric substrates for ■C in the high-frequency region. We can provide dielectric porcelain for use.

Claims (1)

[Claims] 1 General formula (Ba_1_-_vSr_v) (Zr_xZ
n_yTa_z)O_7/_2_-_x/_2_-_3
In the composition represented by _y/_2, 0.02≦v≦
0.13, 0.02≦x≦0.13, 0.28≦y≦0
．． 33, 0.59≦z≦0.65 (however, x+y+z
A dielectric ceramic composition for high frequency use, characterized in that the composition is in the range of =1).