JPH0481104A - dielectric resonator - Google Patents

Abstract

PURPOSE:To realize a dielectric resonator made of a dielectric ceramic composition having a high dielectric constant by forming a dielectric body whose major component is expressed in aCaO.bSr0.cBi2O3.dTiO2 (constants a, b, c are specified) or whose component includes a specific quantity of Tl2O3 and Y203 in addition to the major component cylindrical and providing a conductive film to a prescribed position of its inner and outer surface. CONSTITUTION:The coaxial dielectric resonator is realized, in which a dielectric body having a composition whose major composition is expressed in aCaO.bSr0.cBi2O3.dTiO2 (a, b, c, d are in mol%) and in which the relation of 0<=<30, 0<b<=20, 10<=c<=50, 40<=d<=80 and 0<a+b<=30 exists or whose component includes at lest one kind of a 5wt.% of below of Tl2O3, a 5wt.% of below of Y2O3 and a 1wt.% of below of manganese carbide in addition to the major component, is formed cylindrical and a conductive film is provided in a prescribed position of its inner and outer surface.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electronic component using a dielectric ceramic composition.

(Prior Art) Conventionally, a coaxial dielectric resonator in which a cylindrical dielectric ceramic composition is formed and electrodes are formed on the outer periphery, inner periphery, and one end surface of the cylindrical dielectric material is used in combination with a capacitor. It is widely used as a component of bandpass filters and notch filters, which are components of communication equipment, wireless telephones, etc. The reason for this is that the dimensions of the resonant element can be shortened to 1/v'εr according to the dielectric constant (εr) of the dielectric, which is advantageous for miniaturization, and that by using this dielectric, the temperature It has good stability.

(Problems to be Solved by the Invention) Conventionally, dielectric ceramic compositions for this purpose have an εr of 10 to 1.
There are only 00 materials, and with the demand for miniaturization of electronic devices, E
A dielectric material with r of about 100 to 1000 has been desired.

However, until now, the main material for Er is Ba0
-TiO□-LnO (rare earth oxide) as main component and Pb
Most of the compositions added O, Bi2O, and the Er was 60 to 100.

In view of the above, an object of the present invention is to provide a dielectric resonator using a dielectric ceramic composition having a high dielectric constant.

(Means for Solving the Problems) The inventors have developed a dielectric composition that has already been announced (Japanese Patent Application No. 1983-
A dielectric resonator was formed by focusing on the fact that 267728) has a higher Er than the conventional Er<100.

The present invention provides acao-bsrO-cBi203・dT
The main component represented by io□ (a+ br C, d are mol%
) and 0≦a<30.0<b≦20.10≦c≦50.4
0≦d≦80, but O<a+b≦30 The composition itself or the above main components contain 5% by weight or less of T1□03, 5% by weight or less of Y2O, and 1% by weight of manganese carbonate.
This is a coaxial dielectric resonator in which a dielectric made of a composition containing at least one of the following is formed into a cylindrical shape, and conductive films are provided on predetermined portions of the inner and outer surfaces of the dielectric.

Also, acao・bSrO-cBj, 203・dTi
The main component represented by o2 (a, b, c, d are mol%) is O
≦a<30゜o<b≦20.10≦c≦50.40≦d
≦80, but O<a+b≦30 The composition itself or the above main component contains up to 5% by weight of T1□03, Y
A substrate-type dielectric in which a dielectric material made of a composition containing at least 5% by weight or less of 2O3 and 1% or less of manganese carbonate is formed into a plate shape, and a conductive film is provided on a predetermined portion of the surface of the dielectric material. It is a body resonator.

(Example) Example 1: Main component CaC0,, SrCO3+ B
i□O,, TiO2 each 2.86.1143.28,
57.57.14 mol% was weighed, and Mn was added as an additive.
CO3 was weighed as 0.01% by weight of the main component, put into a polyethylene pot containing an agate ball together with acetone, and wet-mixed for 16 hours.

After heating and drying this slurry, it was sized with a 5-mesh sieve, calcined in the air at 1000°C for 2 hours, and then put into a polyethylene pot containing agate balls together with acetone and crushed for 16 hours. .

After the obtained slurry was dried by heating, a polyvinyl alcohol aqueous solution was added to perform cross-mixing, and the slurry was granulated through a 32-mesh sieve to obtain granules.

The granules were molded in 1t7cxi and placed in air.

It was fired at 1200°C for 4 hours. The obtained fired body has an outer diameter of 1
It was processed into a cylindrical shape with a diameter of 4.0 nn, an inner diameter of 3.9 I, and a height of 14.13 mm to obtain a cylindrical dielectric. Furthermore, as shown in FIG. 1, electrodes 2 (
Electroless copper plating) was applied to form a coaxial dielectric resonator. Then, by using the coaxial dielectric resonator, BPF
(Bandpass filter) 4 that occurs when forming a circuit
Qo was calculated at the peak of 00 MHz. Table 1 shows the measurement results for the five samples.

- A dielectric substrate 3 with 2 sides and 0.6 mm thickness is formed by molding, firing and processing, and as shown in Figure 2, the back front and front side have a width of 1.5 m and a length of 7.0 m +. Electrode 2 was formed. The electrodes were formed by screen printing a silver-palladium-based conductor paste and then firing it at 850°C. Resonance frequency (f,) and Q of these five samples. The measurement results are shown in Table 2.

The length 1 of the coaxial dielectric resonator is the wavelength of the resonant frequency λ
, the volume of the resonator of the present invention is approximately 2 d, and the volume of the resonator of the present invention is approximately 2 d, which is based on the material with the largest εr (εr = approximately 10
0), it is approximately 4.8 d, which is less than 1/2 in volume ratio. As described above, the use of this material greatly contributes to the miniaturization of one communication device and is industrially useful.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view of Embodiment 1 according to the present invention, FIG. 1(b) is a sectional view of Embodiment 2 according to the present invention, and FIG. 2 is a perspective view of Embodiment 2. It is. 1... Cylindrical dielectric, 2... Electrode, 3... Dielectric substrate. Figure 11(b) Figure 2

Claims (2)

[Claims] 1. aCaO・bSrO・cBi_2O_3・dTiO
The main component represented by _2 (a, b, c, d are mol%),
0≦a<30, 0<b≦20, 10≦c≦50, 40≦
d≦80, but 0<a+b≦30. At least one of the following is added to the composition itself or the above-mentioned main components: 5% by weight or less of Tl_2O_3, 5% by weight or less of Y_2O_3, and 1% by weight or less of manganese carbonate. What is claimed is: 1. A coaxial dielectric resonator, characterized in that a dielectric material made of a composition is formed into a cylindrical shape, and a conductive film is provided on predetermined portions of the inner and outer surfaces of the dielectric material. 2. aCaO・bSrO・cBi_2O_3・dTiO
The main component represented by _2 (a, b, c, d are mol%),
0≦a<30, 0<b≦20, 10≦c≦50, 40≦
d≦80, but 0<a+b≦30, and at least one of the following is added to the composition itself or the above main components: 5% by weight or less of Tl_2O_3, 5% by weight or less of Y_2O_3, and 1% by weight or less of manganese carbonate. 1. A substrate-type dielectric resonator, characterized in that a dielectric made of a composition is formed into a plate shape, and a conductive film is provided on a predetermined portion of the surface of the dielectric.