JPS61191557A - Manufacture of ceramic material for dielectric resonator - 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 Field of Industrial Application The present invention relates to a method for manufacturing a ceramic material for a dielectric resonator, and in particular to a method for manufacturing a ceramic material for a dielectric resonator.
The present invention relates to a manufacturing method that can stably obtain a high Q in a short firing time in a%) O, based materials.

Conventional technology In recent years, with the advancement of technology for high-frequency circuits that handle microwaves and millimeter waves (hereinafter collectively referred to as microwaves) with wavelengths of several centimeters or less, there has been active progress in miniaturizing these circuits. It is being

Until now, cavity resonators, antennas, etc. have been used in these high-frequency circuits, but their size is comparable to the wavelength of microwaves, which has been an obstacle to miniaturization. In order to solve this problem, methods have been taken to completely shorten the wavelength itself by using dielectric ceramics with a high dielectric constant1. Among these methods, B a (Z n
'73 N b'/3 ) 03-Ba(ZnlTa2
/3) O3-based materials have a dielectric constant of about 30, and 12Gll
It is known that the value of the unloaded Q of z reaches 14000 (J, Am, Ceram, Soc, vol 6
6°421-423 (1983) J.

Problem Ba (Z”'Ia Nb213) Os Ba (
As mentioned earlier, the Zn '7'l T a'7310s material is an excellent material that exhibits a very high Q in the microwave region, but it cannot be produced using the usual manufacturing method, that is, using B a CO3+ Z as the starting material. O+Nb2O5,T
In the method of simultaneously mixing predetermined amounts of a203f and calcining them, a long firing time is required to obtain a high Q. For example, Ba(ZnV3Ta+!()O).

However, there was a problem in that in order to obtain a Q of 14,000, approximately 120 hours of firing time was required at 1,350°C.

In view of this problem, in the present invention, B a (Z nv3
N b2I3) Os B a (Z nV'(T
a%) The purpose of this invention is to provide a manufacturing method that can stably obtain high Q in a short firing time in 03-based materials. .

Means to Solve All Problems As a technical means of the present invention to solve the above problems, as a result of examining various factors in the manufacturing method, we found that the starting raw material Zn,
It has been found that the above problems can be solved by calcining the Nb and Ta components at a temperature of 750° C. or more and 125° C. or less, and then calcining this and the remaining components again. .

In other words, according to the manufacturing method claimed in the claims of the present invention, by first calcining the Zn, Wb, and Ta components, Z.
By first forming a nNb2O6-ZnTa, 06-based composite oxide having a cooybite type structure and reacting this with the Ba component, Ba(ZnNb2O6)05
In the Ba(ZnMTaM)03-based solid solution, the ordering of Zn, Wb, and Ta is promoted, and a high Q can be stably obtained in a short firing time.

Example starting materials include chemically highly purified aCOs lNb.
O, Ta205. ZnOf was used. After correcting the purity of these, the predetermined amount was calculated. Next, N of these
b2O5, Ta205. ZnO'fr: Weighed and mixed in a ball mill for 17 hours using agate cobblestones and pure water as a solvent. After drying, the mixture was granulated through a 32-mesh sieve, and calcined in air at a predetermined temperature of 760°C to 1250°C for 2 hours. Calcined products and BaCO5k
The mixture was weighed again to a predetermined amount, and mixed using an agate cobblestone and pure water in a ball mill for 17 hours. After drying, add 5 wt% of pure water and granulate it through a 32 mesh sieve.
It was molded at a molding pressure of 1,000 ml, and calcined for 2 hours at 1100° C. in an alumina cracked crucible.

The calcined product was coarsely ground into rice-grain-sized pieces using an alumina back-hole punch, and then ground for 20 hours in a ball mill using agate boulders and pure water as a solvent. After drying this, 8 wt % of 3 wt % polyvinyl alcohol solution was added, and after making it homogeneous, it was granulated by passing through a 32 mesh sieve.
It was molded at a molding pressure of kg r/cU.

The molded body was heated to 700°C in air for 1 hour to burn out the binder, then transferred to a magnesia container and heated at a heating rate of 2.
The temperature was raised to a predetermined temperature at a rate of 00° C./hr, held for a predetermined time, and then lowered.

The dielectric properties were measured by the dielectric resonator method, and the resonant frequency and no-load Q were determined. The resonance frequency is about 12Gllz1. Table 1 shows that in addition to Ba(ZnV3Nb%)OsBa(ZnTaM)05 system, ZnO9Nb205. Ta2
The temperature at which 05 is mixed first and calcined, and the firing temperature is 1350.
No load (l is shown) when firing time is 30 hours at °C.

Samples marked above are comparative examples outside the scope of the claims. Further, in this example, ZnO, Nb2 as starting materials were used.
O,..., Ta205 was used, but the same effect can be expected by using other substances such as hydroxide, carbonate 1, etc.

Table 1 Effects of the Invention As described above, according to the manufacturing method claimed in the present invention, Ba (Znl, 4Nb%)03-Ba (Zn
1, 4Ta%) Since a stable high Q can be obtained in a short firing time in the 03-based material, it is an excellent method for producing ceramic materials for dielectric resonators that is highly suitable for mass production.

Claims (1)

[Claims] Ba(Zn_1_/_3Nb_2_/_3)O_3-B
In the manufacturing process of a(Zn_1_/_3Ta_2_/_3)O_3-based ceramic material for dielectric resonators, the starting material Z
A method for manufacturing a ceramic material for a dielectric resonator, comprising the steps of calcining n, Nb, and Ta components at a temperature of 750° C. or higher and 1250° C. or lower, and mixing and calcining the same with a Ba component again.