JPS5942472B2 - dielectric resonator material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to dielectric resonator materials, particularly Ba〇, SrO, Mg
This relates to a dielectric resonator material composed of O and Nb2O5 components, and is a microwave dielectric material that has a large dielectric constant (ε), a large no-load Q, and excellent temperature stability (τf) of the resonant frequency. The purpose is to provide a composition suitable for

Conventionally, in the microwave region, dielectric materials have been applied to impedance matching of microwave circuits, dielectric resonators, and the like.

In recent years, especially as the integration technology of microwave circuits has progressed, there has been an active effort to use dielectric ceramics with high dielectric constant, low loss, and low cost to stabilize the frequency of oscillators and to miniaturize them. progress is being made. Conventionally, these dielectric materials include BaO-TiO2 compositions, compositions in which some of them are replaced with other elements, and TiO2 whose dielectric constant changes with negative temperature and TiO2 whose dielectric constant changes with temperature at a positive dielectric constant. In many cases, combinations of dielectric and dielectric compositions are used. However, these have many practical problems, such as large dielectric loss, large variations in temperature change in dielectric constant, and too high stability of resonance frequency.
The present invention eliminates these drawbacks, and the BaO-S
In the dielectric composition system composed of r0-MgO-Nb2O5, 3(Bal-xSrx)O.

This invention is based on the discovery that a solid solution composition of MgO-yNb2O5 can be synthesized as an excellent material for dielectric microwave resonators. Here, the material of the present invention has a composition formula of 3(Bal-xSrx)O-MgO.yNb2O5, where 0<X<1|・0.5≦y≦1.
5. The present invention will be explained below based on Examples.

First, BaCO3, SrC03, MgO, and Nb2O
Starting materials No. 5 were weighed according to each composition and wet mixed in a ball mill equipped with an agate ball and lined with rubber. This mixture was dried and then heated to 1200°C in air.
After calcining for 5 hours, the mixture was wet-pulverized in the ball mill.
After drying it, it was formed under a pressure of 700 kg/C7l and fired in air at a temperature within the range of 1460 to 1360°C for 2 hours to obtain samples having the compositions shown in the table below. Then, the dimensions of each sample were determined to be approximately 5 mm in diameter and 2 mm thick.
mm, the permittivity (ε) can be determined from its resonant frequency (approximately 11 GHz) and diameter, and the unloaded Q (
Qu) was measured. The temperature stability (τf) of the resonant frequency is determined by placing the dielectric resonator made of each sample in a temperature bath and setting it at -30
The trap frequency was determined by measuring the change in trap frequency as the temperature changed from °C to +70 °C. The results are shown in the table below. As is clear from the table, the composition of the present invention has a relatively large dielectric constant, a large no-load Q, and
Furthermore, it can be seen that it is an excellent material with improved temperature stability of resonance frequency.

Claims (1)

[Claims] 1 General formula 3 (Ba_1_-_xSr_x)O.MgO.yNb_2
In the composition represented by O_5, 0<x<1, 0.5
A dielectric resonator material characterized in that ≦y≦1.5.