JPS59228310A - Microwave dielectric porcelain composition - 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 The present invention provides Ba (Co, Nbz) Oj-Ba
(Z''/aN b-/,) 0. The present invention relates to a dielectric ceramic composition for microwave use.

In recent years, resonators, filters, and the like made of dielectric materials have been used in car telephones and satellite broadcasting receivers that utilize microwaves. Dielectric materials used in such applications are required to have a high dielectric constant, low loss, and high stability. 3aQ-T, which is conventionally used while
The tQ-based or Zr 2 O, -SnOz-Ti 2 O, based dielectric materials cannot be said to have sufficiently small dielectric loss, nor do they have sufficiently satisfactory temperature stability. In particular, as circuit technology improves, the overall performance of devices incorporating dielectric materials (e.g., high temperature stability) is sought after, and the dielectric materials used in the peripheral circuit parts, etc. It is required to have characteristics that can perform temperature compensation suitable for the temperature characteristics.

The purpose of the present invention is to further improve the properties of these conventional dielectric materials, to create a microwave dielectric material that exhibits a higher dielectric constant, lower loss, and can freely adjust the temperature coefficient of the resonant frequency. An object of the present invention is to provide a porcelain composition.

In the present invention, by forming a solid solution of B a (Co, N b,...) O and Ba (Zn, 7°N bH) O ) was completed based on the knowledge that the electrical characteristics of the resonant frequency were significantly improved and that the humidity coefficient of the resonant frequency could be freely adjusted to a desired value by changing the composition ratio.

The present invention will be explained in more detail below.

The present invention provides B a (G 0 IAN 11%) Os
and Ba(Znt/.

A dielectric ceramic composition consisting of a solid solution with N b, A) Oh. The composition ratio of the solid solution may be completely arbitrary. Here, when the composition is expressed by the general formula (1% formula %) 0, as the value of composition ratio x increases, the temperature coefficient τ of the resonance frequency becomes negative (about -10 ppm/℃)
The gusset changes almost linearly from the positive side (approximately +30 ppIIl/°C). Therefore, in reality, the value of x is determined to provide the optimum temperature coefficient depending on the requirements of the device in which the resonator or filter using the dielectric material is installed.

The manufacturing method may be a conventional powder molding method. That is, the calcined powder may be granulated by adding an organic binder, pressure-molded into a predetermined shape, and then fired.

As mentioned above, the present invention provides B a (Cr Oy, N
bys') Oa and B a (Z nHN b〃)
By forming an @ solution with OB, the dielectric loss is sufficiently small and the temperature coefficient of the resonant frequency can be freely adjusted in a wide range from the negative side to the positive side, but the more preferable value of composition ratio x is 0.15 (X (0.75).

Within this range, the temperature coefficient τf of the resonant frequency is -5
This is because it can be kept within the range of ~+20 (ppm/°C). This is based on a request from the equipment side.
This is because it is generally desired that the value can be adjusted to any value within this range and that the loss is low.

Next, an experimental example will be described.

Example 1 Ba (Cod) obtained by firing at 100°C for 6 hours
N l)%) Oa and 3a (ZnxNby,) O
The raw material powders in a were weighed and blended, pulverized in a ball mill for 40 hours, and dried. Add an organic binder such as polyvinyl alcohol to this, granulate it, and
Molding is performed at a pressure of 0 kQ/Cf. Next, this molded body is
Bake at a temperature of 350-1500°C for 2-40 hours. By processing this fired product into cylinders with a diameter of 12111 + 11φ and a height of 5.5 mm, 7
Various samples were obtained. Then, the dielectric constant ε, the dielectric one-member loss tan δ, and the temperature coefficient τf of the resonance frequency were measured by the dielectric resonator method. Ill constant) frequency is approximately 6.5G HZ
It is.

Table 1 shows the composition ratio X and electrical characteristics of each sample.

Note that here, Q = 1/tan δ, and the unit of τ( is ppm/°C. Also, *m1 indicates the case of a more desirable composition ratio. Temperature coefficient of resonance frequency with respect to composition ratio X The graph of is shown in the drawing.As is clear from this drawing, as the value of the composition ratio Approximately +30
The negative side hX, 1, and 11 changes almost linearly up to ppm/°C. 1. Both the dielectric constant and the dielectric constant tend to increase slightly as the set ratio X increases.

On the other hand, Q tends to decrease slightly in the middle part (0, 3 (x (0, 7)), but it has a good value of 6000 or more regardless of the deviation. The resonant frequency temperature coefficient can be freely adjusted over a wide range (one range) by simply changing the .

The present invention is based on the above Y(D, B a (Coy, N 1
+=A) 08 and B a (Z n,, N b,, >
By forming a solid solution with o, it is possible to increase the dielectric constant and extremely reduce dielectric loss in the microwave band, and also to increase the temperature coefficient of the resonant frequency over a wide range from the negative side force to the positive side. It has many outstanding effects, such as being able to freely adjust the dielectric material and therefore significantly improving the temperature stability of devices incorporated with microwave resonators and filters made of this dielectric material. It is Uchino who plays.

[Brief explanation of the drawing]

The drawing is B a (Z n/l, N b2/,) o
, is the humidity coefficient of the resonant frequency with respect to the change in the composition ratio x of
Fig. 1 shows the changes in . Patent Applicant: Fuji Electrochemical Co., Ltd.
Shigeru Makido Araki Tomonosuke #L Be Rin X

Claims (1)

[Claims] 1, B a (G O, IN b%) Os
A dielectric ceramic composition for microwave use, comprising a solid solution of B a (Z n,, N b,,) ON.