JPH03263707A - Dielectric porcelain composition - Google Patents

Abstract

PURPOSE:To obtain a dielectric porcelain composition with a high specific dielectric constant, a small temperature coefficient of resonant frequency varied in a wide range from the plus side to the minus side by specifying the composition ratio of the composition made of barium oxide, nickel oxide, niobium oxide, strontium oxide, and zinc oxide. CONSTITUTION:The composition formula of a dielectric porcelain composition is expressed by (1-X)Ba(Ni1/3Nb2/3)O3-XSr(Zn1/3Nb2/3)O3, and its constituent composition is within 0.4<=X<=0.9wt.%. The dielectric porcelain composition has a large dielectric constant about 37 and the relatively large no-load Q 7000 or above, and the temperature coefficient of resonant frequency is varied in the wide range (+50)-(-25)ppm/ deg.C. This dielectric porcelain composition is very useful for the TE01delta mode resonant element for stabilizing the frequency of a local oscillator circuit for the down converter of a satellite transmission/ reception antenna section and the material for various communication ceramic elements. It can be also used as the material for a microwave integration circuit board and a high-frequency power capacitor.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a dielectric ceramic composition with a high dielectric constant, and in particular has a high dielectric constant, a relatively large no-load Q value, and a small temperature change in resonant frequency. , and has a high dielectric constant having a wide range of values from positive values to negative values [Conventional technology] High dielectric constant dielectric fiff device string used as S plate (conventionally, microwave collector circuit) and inductor material for high frequency power Among the powerful materials, 13ao-Ti02 series dielectric porcelain &amp;
Il-based materials were often used.

However, with these materials, it was not possible to obtain an unloaded Q of 5000 or less, or a negative value of the temperature coefficient '1' of the resonance frequency.

Therefore, for example, if the entire microwave circuit has positive temperature characteristics, f+
By using a circuit with a temperature characteristic of , the temperature dependence of the frequency is made zero for the entire circuit. It could not be used as a so-called temperature compensation dielectric element.

In order to improve these points, BaO, SrOlNbgO
Dielectric materials containing s as a component (for example, JP-A-55-104
49) and 5r (Ni,.

,Nt)z/3)03,Ba(Ni+z3
Nbtis)03, SrZrO3, BaZr03
(7) A dielectric ceramic composition consisting of four sheets has been proposed (see, for example, Japanese Patent Laid-Open No. 61-61.76).

[Problem to be solved by the invention]

However, these dielectric materials &! The part name of the component R is that the temperature coefficient of the dielectric constant is 3 digits, which is a large sum, and the latter has a relatively low dielectric constant of about 29 to 32, so it does not necessarily meet the above conditions. It wasn't something.

Therefore, 1-1 of the present invention has a high dielectric constant of about ε-37, a high value of 11-free Q of 7000 or more, and a small temperature coefficient of resonance frequency, and a wide range of implants from the busis side to the negative side. This paper presents a dielectric material and a transducer material U4 that takes the following values.

[F stage for solving problems]

In order to achieve the above-mentioned L1 target, the present inventor conducted extensive research and found that barium oxide J2, chive oxide, dioxide, oxidized chloride [1 inch. The composition formula (l X)! %a(Ni+zJhz/,)0:+-X
Sf (ZnizJbyy>) 03 and f: 15, ri 17
) It has been found that a dielectric ceramic composition having a component composition in the range of 0, -°'.

(Function) Each time the dielectric ceramic composition of the present invention is used,
ε-37 culm degree and high relative dielectric constant, Asahi load Ω is 700
It was possible to obtain a dielectric ceramic composition having a relatively large temperature coefficient of 0 or more and a temperature coefficient of a resonance frequency as wide as +5 Op pm---25 pp pm.

〔Example〕

An embodiment of the present invention will be described.

Starting material/: L-i7 Commercially available i7) It a CO3,
The composition of Ni01Nb205, S r C03, and ZnO after the boundary is 4-4.
Ru.

That is, its composition J: (, (1-X)Ba(Ni+zJbzy:+)03-XSr
When expressed as (Zri+zJbzz)03(1), it is automatically scaled to Table 1, which will be described later, in the range of 0.≦X≦i.

The weighed starting materials were wet-mixed in a ball mill for 20 hours, dehydrated and dried, and mixed at 1000 to 12
Temporarily bake for an hour.

Next, this pre-calcined body was finely ground, and the resulting rice powder was granulated with an appropriate amount of binder.
A cylindrical molded product with a height of 7ynm is created.

The cylindrical molded product is heated stably at about 2 intercostals at 1350 to 1600 ''C and then subjected to main firing.

The obtained dielectric ceramic set pli has a diameter of 10 nm.
,.

Pressure is applied to a cylindrical body with a height of 5 mrn.

Next, depending on THo and mode of the resonator, which is made up of a σ) circle jt body sandwiched between two parallel metal plates, the temperature is 25℃7
('; Relative permittivity at Hz and no 11, martyrdom (),
Measure.

Also, the resonant frequency temperature coefficient ゛1゛□ is from -40℃ to 180℃.
Calculate from the change in resonance frequency due to temperature change in °C.

The measurement results are shown in Table 1.

Go to 4゛i, in the table I, sample kl with index mark I=J
, 2, ;(, 4, 5, 17, 10, 19 do not include the implementation number 8' of the present invention.

As is clear from Table 1, the dielectric ceramic composition of the present invention contains the components &II in the compositional formula as shown in (1) below.
IIi.

The fraction of weight 11 is in the range of 0.4≦X≦0.9.

This is because when X = less than 0.4, the dielectric constant ε is 36
．． In addition to being as small as 1 or less, the no-load Q is also as small as 7000 or less (for example, see Sample N [L1 to L5 in Table 1).

Furthermore, when X = 0.9 is exceeded, the no-load Q is 600.
It becomes relatively small, 0 or less, and the object of the present invention cannot be achieved (for example, see Sample N [L17 to 19 in Table 1)].

〔Effect of the invention〕

The dielectric ceramic composition of the present invention has a high relative dielectric constant of approximately 37 fa degrees, a relatively large no-load Q of 7000 or more, and a temperature coefficient of resonant frequency of +50 to 25 pp m/
``C varies over a wide range.

Therefore, the dielectric ceramic composition of the present invention is very useful as a material for various communication ceramic elements, including TEo1δ mode resonant elements for frequency stabilization of local oscillation circuits for down converters in satellite broadcast receiving antennas. .

Furthermore, it can be used as a material for microwave integrated circuit boards and high-frequency power capacitors.

Claims (1)

[Claims] Consists of barium oxide, nickel oxide, niobium oxide, strontium oxide, and zinc oxide, whose composition formula is (1-X)Ba(Ni_1_/_3Nb_2_/_3)
O_3-XSr(Zn_1_/_3Nb_2_/_3)
When expressed as O_3, the component composition is 0.4≦ in weight fraction
A dielectric ceramic composition characterized in that X≦0.9.