JPS62157609A - Radio frequency dielectric porcelain compound - 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> This invention relates to a dielectric ceramic composition for high frequency use.

<Prior Art> Dielectric ceramics have been widely used in dielectric resonators, dielectric substrates for MIC, and the like in high frequency regions such as microwaves and millimeter waves.

In this case, the Q value is high and the temperature coefficient of the resonance frequency (τf
) is approximately OI)l)m/'C. For example, as a high Q value, JP-A-58-
45155, the general formula Ba(ZrX
z” yTaZ 〉0.02≦x≦0.13.0.2 in the composition represented by 07/2-X/2-37/2
8≦y≦0.33.0.59≦z≦0.65, (however,
x+y+z=1) and the general formula Ba""v"xTayNbz)07/2- disclosed in JP-A-58-60661
In the composition expressed as 3v/2-3x/2, 0.0
3≦■≦0.33.0, 03≦x≦0.33, O≦y
≦0.70, O≦Z≦0.70 (however, v+x
A dielectric ceramic composition is known which is characterized in that it lies in the range of +y+z=1>.

The former material made of Ba (ZrZnTa)O has a Q value of 91 at 7GH2 in the microwave band.
00 (however, temperature coefficient of resonance frequency (τf) = 1
ppm 7°C), and the latter Ba (ZTI NL T
aNb) Those made from O-based materials have a Q value of 1030.
0 (However, temperature coefficient of resonance frequency (τf) = OpI
)m/'C:).

<Problems to be Solved by the Invention> However, recently, the frequency range used has become even higher, and materials with a correspondingly higher Q value are required.

To improve this Q value, Ba <”lr, ZTI
, Ni.

Ta, Nb) 03 series materials and N of these
Materials are provided in which L is replaced with 6. However, the firing temperature of these materials is as high as 1550° C., which is a major obstacle to improving productivity and has the drawback of increasing costs.

<Means for Solving the Problems> In view of the above, the main purpose of the present invention is to provide a dielectric porcelain composition that has a higher Q value than conventional ones in the high frequency range, can be fired at low temperatures, and is highly productive. By providing things.

That is, the present invention is based on the general formula Ba ("lr x Zn
y NL z TaU NbV )07/2-X/2-
3y/2-32/2'' In the composition represented, o,
oi≦x≦0.06.0.28≦y≦0.33, 0
．． 01 ≦z≦ 0.05 , 0.52 ≦u≦0.6
5, O≦V≦0.13 (However, x + y + z + u +
v=1) and NL is (NL 1-w C
The main component is a substance substituted in the range of 0≦w≦1, which is written as 0 w ＞, and a lanthanide oxide is added to this
When expressed as 2 o3, at least 1 of the Me2O3
This is a dielectric ceramic composition for high frequency which contains 0.05 to 2.0 mol% of seeds.

<Operation> According to the present invention, the Q value in the microwave band is higher than the conventional one, and is higher than that in the 1-10GH2 band, which is 10-50.
A high-frequency dielectric ceramic composition can be obtained that can be used up to the GHZ band, has a good temperature coefficient of resonance frequency, and has a high dielectric constant.

Here, the addition of lanthanide oxides is 15
High temperature firing around 50'C is required (Zr Zn
This makes it possible to obtain a good sintered body by sintering the NLTaNb)03-based material at a lower temperature of 1450 to 1500'C without lowering the Q value.

<Example> Hereinafter, this invention will be explained in detail with reference to Examples.

High purity BaCO3, ZrO2, ZTIO, NLO, T
a205, Nb205, CO203 rough La2O3
, Nd203, Sm2O3, LeO1Pr203, etc., were weighed so as to obtain porcelain having the composition shown in Table 1, and the weighed raw materials were wet mixed for 2 hours.

Next, the mixture was calcined at 1200° C. for 2 hours, and a binder was added to the colander and wet-mixed again for 2 hours, followed by dehydration and sizing.

The powder thus obtained was molded into a disk with a diameter of 12 mm and a thickness of 6 mm under a pressure of 2000 KgJ.
A porcelain sample was obtained by firing at 450-1500°C for 4 hours.

For this ceramic sample, the dielectric constant (ε, ), Q value, and temperature coefficient of resonance frequency (τf) at a frequency of 7GH2 were measured. The results are shown in Table 1. The dielectric materials marked with * in the table are outside the scope of this invention, having been fired at 1550'C for 4 hours, and all others are within the scope of this invention.

The following relationship is established between the temperature coefficient of frequency (τf), the temperature change rate of dielectric constant (τ5), and the linear expansion coefficient α of the ceramic sample.

τf=−1/2τ5−α The reason for limiting the composition range of the high frequency dielectric ceramic of the present invention is as follows.

(1) Sintering does not occur when x<0.01. Also x>0
．． 06, the Q value decreases, which is not desirable (sample number 23
reference).

(2) No sintering when V<0.28 or y>0.33.

(3) No sintering when z < 0.01 (sample number 2
In addition, when Z>0.05, the Q value decreases, which is not preferable (see sample number 21).

(4) Sintering does not occur when u≦0.52 or u>0.85.

(5) When ■≧0.13, the Q value decreases (see sample number 24).

<Effects of the Invention> As described above, the present invention exhibits a high dielectric constant, and as for the Q value, the temperature coefficient of the resonance frequency r f = 1
Since it exhibits a value of 17,500 in ppm/'C, it is possible to obtain a high-frequency dielectric ceramic with a Q value 1.7 times higher than that of conventional materials.

Claims (1)

[Claims] General formula Ba(Zr_xZn_yNi_zTa_uNb_v)O
＿7＿／＿２＿−＿x＿／＿２＿−＿３＿y＿／＿２＿
In the composition represented by −_3_z_/_2, 0.0
1≦x≦0.06, 0.28≦y≦0.33, 0.01
≦z≦0.05, 0.52≦u≦0.65, 0<v≦0
．． 13 (however, x+y+z+u+v=1), and when Ni is written as (Ni_1_-_wCo_w), the main component is substituted in the range of 0≦w≦1, and lanthanide-based oxides are added to this. is expressed as Me_2O_3, at least one of the Me_2O_3 is 0.05
A high frequency dielectric ceramic composition containing 2.0 mol% of .