JPS59196505A - High frequency 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 relates to a dielectric ceramic composition for high frequency use.

In high frequency regions such as microwaves and millimeter waves, dielectric ceramics are widely used for dielectric resonators, dielectric substrates for IVI IC, and the like.

Conventionally, as this type of dielectric porcelain, for example, Zn 02
- Sn 02-T', 02 series material, Ba2Tjl
OJ6. (Ba, Sr) (7,r, Ti)
There are Ch-based materials, Ba (Zn, Ta) 03-based materials, etc.

These various materials have a dielectric constant (Sr) in the microwave band.
is reported to have characteristics of 20 to 40, Q of 4,000 to 8,000, and a thirst coefficient vl(τf) of the resonance frequency of approximately O1'1llll/°C i4.

15. Ba (Zn, Ta) Os-based material 1 is a suitable conventional example of the present invention. This day a (7T1
．． Regarding Ta) 03 series materials, see JP-A-53-3!145.
There is a detailed explanation in Publication No. 4! [It has been.

According to its detailed description, 1360~. Dielectric porcelain was obtained by firing in air for 2 hours at a temperature range of 1460°C, and its size was set to 5 mm in inner diameter and 2 mm in thickness, and the resonance frequency (
Habo 11QI”? ) and the dielectric constant), and also measured the zero charge Q using the band reflection method, and the humidity coefficient (τchi) of the resonant frequency in the temperature range of -30℃ to +70℃, and found that for 4. 25 to 30, and 3520 for Q, and 5 to 20 ppm/°C for 3730 and l.

Recently, the following reports have been made regarding this Ba(Zn, Ta) 03-based material.

In other words, for Ba (χη, Ta) 03, dielectric porcelain was fired using the normal firing method, but the firing conditions were set to a maximum temperature of 1650°C and a firing time of 2 to 1.
The results are considered over a 20 hour period.

According to this, porcelain fired for 120 hours showed a Q value of 14,000 when measured in a waveguide, and when porcelain fired for 2 hours was measured using the same method (12G
HZ) 10,000 to 11,000 (7) It is said to indicate the Q value.

The reason for the change in Q value due to firing time is as follows.

First of all, Ba (Zn!4Nby,) 03 is "Q r
dcring in Com-pounds o
f the A (s,',, Tag, 47)
Os T Vne”, r, Ga1asso and
J, Pyle, Inorganic Che
mistry, vol12. l'Je, 3. p 4
82-484, it has a cubic composite velorskite structure consisting of ΔBo3, and its crystal structure is hexagonal (@exagona) due to the Kawaguchi II arrangement of 7Tl and Ta. l) forms a superlattice.

jl - Figure 1 shows the crystal structure of this Ra (ZnJaΩ03), in which 7.n 1 and Ta 2 at the B position are 1:
2 has an ordered arrangement. a33 represents l'3a, and 4 represents O.

However, this ordered structure Ll and the fired strip A' [and J-] vary greatly. That is, as shown in FIG. 2, the firing temperature was set to 13! When we investigated the dependence of the (422) and (226) reflection patterns on the firing time in X-ray diffraction of porcelain at 10°C, we found that the formation of an ordered arrangement of Zn and Ta was insufficient with a firing time of about 2 hours. can be,
On the other hand, it is explained that at a firing time of 120 hours, Zn and Ta are sufficiently ordered, and this leads to an improvement in the Q value.

However, in order to produce porcelain with a high Q value, maintaining the firing time for as long as 120 hours is a major obstacle to improving productivity and increases costs.

In addition, operating the furnace or forming furnace for a long time at a high temperature of P 12 Q Il','i shortens the life of the firing furnace, which also leads to loss of high quality products. Especially Irro.

Recently, the frequency range used has become even higher, and a material P1 with an even higher Q value is required in response to this.

In view of the above points, the present inventors have conducted extensive research and found that it does not require a long firing time, has a high dielectric constant in the high frequency range, has a high Q value, and has a temperature coefficient of Orlnm / We have discovered a dielectric ceramic composition for high frequencies that can obtain any value centered around °C.

That is, the gist of this invention is that BaO17, r
02, ZTlO1Ta20. When this is expressed as the general formula Ba (Zy%Zn, TaL) 0%-%-"X, x, y, and z are o.

2≦×≦ 0.13.0.28≦y≦0.33.0.5
The main component is one in the range of 9≦7≦0.65 (however, x+y+z=1), and 70 atomic % or less of ZTl is substituted with either NL or Co, or both, and Y2O3 is added to this. This is a high frequency dielectric ceramic composition containing 0.1 to 1.0 mol%.

Here, Ba (Zr, Zn, Ta, > Qs-+54-
At 1%, x, y.

4-Z is limited to a range of 1 yaku (shi) each from the next ii T sokuyama.

The reason for setting X in the range of 0.02 to 0.13 is that if X is less than 0.02, Q will decrease;
This is because if it exceeds 3, the jt resonance frequency temperature coefficient becomes large on the positive side.

The reason (2) is set to 0.28 to 0.33 is because if this value is less than 0.28 or exceeds 0.33, sintering becomes difficult.

The reason why 7 is set to 0.59 to 0.65 is because if l is less than 0.59, and if it exceeds 0 or 65, sintering becomes difficult.

Also Fla (ZrllZn, Ta,) oya-%-
'% of Zn is replaced by N1 or either or both, the amount of substitution is 70 atomic % or less and 1 is 7
This is because the temperature coefficient of the resonance frequency becomes too large on the negative side when the temperature exceeds 0%.

Next, the amount of Y2O3 added to the above V component is 0.
The reason why it is specified as 1 to 1.0 mol % is that below 0.1 mol %, there is no effect of increasing the Q value, and above 1.0 mol %, the dielectric constant and Q value decrease.

This invention will be explained in detail below with reference to Examples.

Example m High purity Ba CO3,7,r Op as PI,
'In O, Ta 2or, NjO, (', 0203
, Y203, the weighed raw materials were placed in a rubber-lined ball mill together with agate stone and pure water, and mixed in a groove for 2 hours. Next, this mixture was dehydrated and dry-bombed, and then heated to 1200°C.
Calcined for 2 hours, then put this calcined product in a ball mill with an agate stone.
The mixture was placed in either pure water or an organic binder and subjected to groove pulverization for 2 hours.

Next, after drying this pulverized product, it was granulated by passing through a 50 mesh mesh, and the obtained powder was molded into a disk with dimensions of 12 mmφ x 6 mm at a pressure of 2000 kaJ9. The sample was fired at ℃ for 4 hours, yielding 1 q of porcelain samples.

The dielectric constant (ε), Q, and temperature coefficient (-) of the resonant frequency were measured using the vibrator method for the dielectric material 4 at a frequency of 7GH7, and the results are shown in Table 1.

(1) In Table 1, the items are outside the scope of this invention, and everything else is within the scope of this invention. 1 Table 1 = 23 - 1 in Table 1 , Trial 1'!1 Number 1 , 441 ,
, '+ 2, 55t; I: Part of 7□ left N1. CA
The composition that can be obtained by replacing any one of Gj,〃h/)
1゜'', which is outside the scope of the invention of
fFi is 70 atomic%.
It is excluded from the scope of this invention.

Trial number wing 1, 2, 3.10.1 ['i, 17, 2:i
,70,3(1,36,42,43°49.52.55
is an example in which Y2O3 is not added, and is an example of this invention! i
It's outrageous.

Next IZ KL i'l number 9.15, 22, 28, 3
Adding 5,4L48tJ, Y2O3 in an amount of 1.01% or more lowers the lightning resistance and QIff, so it was excluded from the scope of this invention.

Further trial 1'1 month 1-571;1. Ba (7, r
,7. TI, Ta7. > Oy, -1, -f×, ■, 7
The value of 1) is out of the range of the present invention, and sintering is difficult, and the values of f11, f, and t are decreased.

For exam 1' + 1st month/19, 50, 52.53,
The characteristic f1 is not shown because sufficiently sintered porcelain could not be obtained and it was impossible to measure the characteristic.

As detailed above, according to the present invention, it is possible to obtain a dielectric ceramic composition for high frequencies which has a high dielectric constant and exhibits a high Q value which has not been previously obtained by adding Y2O3. In addition, by appropriately selecting a base in which a part of Zn is replaced with either or both of NLl, etc., the temperature coefficient of the resonance frequency can be set to any value on the positive or negative side around Oppm/°C. It is.

Therefore, according to the present invention, it is possible to provide a high frequency dielectric ceramic composition useful for applications such as dielectric resonators, dielectric adjustment rods, and dielectric substrates for MIC.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the crystal structure of Ba (Z++xTag) 03, and FIG. 2 is an X-ray diffraction diagram of Ba (ZnNa%) 03 shown in relation to firing time. Patent applicant Murata Manufacturing Co., Ltd.

Claims (1)

[Claims] It consists of BaO, ZrO2, ZTIO, Ta20r, and is expressed by the general formula Ba (Zy, Zn, TaJ 0%-%-%
When expressed as, x, y, and Z are 0.02≦×≦0.13
．． 0.28≦y≦0.33.0.59≦2≦0.65
(However, x+y+z=1) and Zn
The main component is one in which 70 atomic percent or less of
．． A high frequency dielectric ceramic composition containing 1 to 1.0 mol%.