JP2768455B2 - Dielectric porcelain and dielectric resonator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The invention relates in particular to microwaves,
The present invention relates to a dielectric porcelain or a dielectric porcelain composition and a dielectric resonator used in a high frequency region such as a millimeter wave band.

[0002]

2. Description of the Related Art In recent years, dielectric porcelain has been widely used for dielectric resonators, filters, and the like in a microwave or millimeter wave region having a wavelength of several cm or less (hereinafter, these are collectively referred to as microwaves). The dielectric material used in such an application has a high unloaded Q (Qu) value, a large relative permittivity (ε _r ), and can arbitrarily change the temperature coefficient (τ _f ) of the resonance frequency, that is, a desired value. Is required.

Conventionally, various materials have been reported as materials suitable for such uses, and ZrTiO ₄ -based porcelain is one of them. ZrO ₂ —SnO ₂ —TiO
One example is a _two- system porcelain.
No. 769, ZrO ₂ -SnO ₂ -T
iO ₂ -MgO porcelain and ZrO ₂ -SnO ₂ -TiO ₂ -CoO proposed in JP-A-2-192460.
-Nb ₂ O ₅ porcelain, and the like are known.

[0004]

However, ZrT
Although the iO ₄ porcelain has a large relative dielectric constant of 45, the temperature coefficient of the resonance frequency is 54 ppm / ° C., which is large on the positive side.
The temperature coefficient of the resonance frequency fluctuates greatly due to the thermal history during firing. In the ZrO ₂ —SnO ₂ —TiO ₂ based porcelain, the temperature coefficient of the resonance frequency achieves a small value near 0 ppm / ° C., but there is a problem with the fluctuation of the temperature coefficient of the resonance frequency due to the heat history.

Further, conventional materials have various problems such as a low relative dielectric constant, a low unloaded Q value, and a failure to achieve a desired temperature coefficient of resonance frequency.

Further, in general, the product of the resonance frequency (f) and the Qu value is assumed to be constant for the same material. However, in practice, when f decreases (ie, when the element is made larger).
The fQu product is significantly deteriorated (reduced). Therefore, it is strongly desired that a microwave dielectric element such as a dielectric resonator for a mobile communication base station used in a relatively low frequency range has a higher unloaded Q value. . Further, since a dielectric resonator used in a relatively low frequency region becomes very large, it is strongly desired to further reduce the size.

A first object of the present invention is to provide a conventional ZrTiO.
_{In order} to reduce the variation of the temperature coefficient of the resonance frequency due to the heat history during firing of the ₄ series and ZrO ₂ -SnO ₂ -TiO ₂ series porcelain .
It is an object of the present invention to provide a dielectric ceramic having a specific composition . A second object of the present invention is to provide a dielectric ceramic having a high unloaded Q value, a large relative permittivity, and capable of arbitrarily changing a temperature coefficient of a resonance frequency (that is, a temperature coefficient of a desired value). It is to be.

[0008] Further, a third object of the present invention is to provide 0.8 to 5 parts.
An object of the present invention is to provide a small TE ₀₁ δ-mode dielectric resonator having a high unloaded Q value in a frequency range of GHz. The present invention seeks to achieve one or more of the three objects of the present invention.

[0009]

Means for Solving the Problems In order to achieve the above object, each invention of the present application has the following arrangement.

(1) Both Zr and Ti components and ｛Mg, C
o, Zn, Ni, Mn} at least one component selected from the group (A) and {Nb, Ta} the group (B)
From a composite oxide with at least one component selected from
Consisting of dielectric ceramic.

(2) The composition formula is xZrO ₂ -yTiO ₂
A group (A) in which the symbol A is composed of {Mg, Co, Zn, Ni, Mn} when expressed by −zA _{(1 + w) / 3} Nb _{(2-w) / 3} O ₂
At least one component selected from the group consisting of
A dielectric porcelain composition in which y, z, and w are in the ranges shown by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following).

[0012]

(Equation 5)

(3) The composition formula is xZrO ₂ -yTiO ₂
A group (A) in which the symbol A is composed of {Mg, Co, Zn, Ni, Mn} when represented by −zA _{(1 + w) / 3} Ta _{(2-w) / 3} O _2.
At least one component selected from the group consisting of
A dielectric porcelain composition in which y, z, and w are in the ranges shown by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following).

[0014]

(Equation 6)

(4) @Mg, Co, Zn, Ni, M
a ZrTiO ₄ phase or crystallographically in which at least one component selected from the group (A) consisting of n} and at least one component selected from the group (B) consisting of {Nb, Ta} are solid-solution substituted; The above (1) having a ZrTiO ₄ phase as a main component
A dielectric porcelain according to Item.

(5) @Mg, Co, Zn, Ni, M
a ZrTiO ₄ phase or crystallographically in which at least one component selected from the group (A) consisting of n} and at least one component selected from the group (B) consisting of {Nb, Ta} are solid-solution substituted; A ZrTiO ₄ phase as the main component, and a / b
(However, the symbols a and b are the groups (A) and (B), respectively)
(Indicating the sum of the mole fractions of the components) is 0.5 or more and 1.0 or less.

(6) Both Zr and Ti components and ｛Mg, C
o, Zn, Ni, Mn} at least one component selected from the group (A) and {Nb, Ta} a group (B)
From a composite oxide with at least one component selected from
Consisting consisting dielectric ceramic TE ₀₁ [delta] -mode dielectric resonator.

(7) The composition formula is xZrO ₂ -yTiO ₂
A group (A) in which the symbol A is composed of {Mg, Co, Zn, Ni, Mn} when expressed by −zA _{(1 + w) / 3} Nb _{(2-w) / 3} O ₂
At least one component selected from the group consisting of
TE ₀₁ δ-mode dielectric composed of dielectric porcelain in which y, z, and w are in the ranges represented by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following): Body resonator.

[0019]

(Equation 7)

(8) The composition formula is xZrO ₂ -yTiO ₂
A group (A) in which the symbol A is composed of {Mg, Co, Zn, Ni, Mn} when represented by −zA _{(1 + w) / 3} Ta _{(2-w) / 3} O _2.
At least one component selected from the group consisting of
TE ₀₁ δ-mode dielectric composed of dielectric porcelain in which y, z, and w are in the ranges represented by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following): Body resonator.

[0021]

(Equation 8)

(9) @Mg, Co, Zn, Ni, M
a ZrTiO ₄ phase or crystallographically in which at least one component selected from the group (A) consisting of n} and at least one component selected from the group (B) consisting of {Nb, Ta} are solid-solution substituted; The TE ₀₁ δ-mode dielectric resonator according to the above mode (6), comprising a dielectric ceramic mainly composed of a ZrTiO ₄ phase.

(10) @Mg, Co, Zn, Ni, M
a ZrTiO ₄ phase or crystallographically in which at least one component selected from the group (A) consisting of n} and at least one component selected from the group (B) consisting of {Nb, Ta} are solid-solution substituted; A ZrTiO ₄ phase as the main component, and a / b
(However, the symbols a and b are the groups (A) and (B), respectively)
(Indicating the sum of the mole fractions of the components) is 0.5 to 1.0.
₀₁ δ mode dielectric resonator.

[0024]

According to the structure of the dielectric ceramic of the present invention described in the above item (1), ZrTiO ₄ and ZrO ₂ —SnO ₂ —T
It is possible to provide a dielectric ceramic in which the fluctuation of the temperature coefficient of the resonance frequency due to the heat history at the time of firing the iO ₂ ceramic is reduced. According to the configuration of the dielectric porcelain or the dielectric porcelain composition of the present invention described in the above (2) to (5), the unloaded Q value is high, the relative dielectric constant is large, and the temperature coefficient of the resonance frequency is high. Can be arbitrarily changed, and a dielectric porcelain or a dielectric porcelain composition can be provided.

According to the TE ₀₁ δ-mode dielectric resonator of the present invention described in the above items (6) to (10),
Has a high no-load Q in the frequency range of 0.8 to 5 GHz,
In addition, a small dielectric resonator can be realized.

[0026]

EXAMPLES As starting materials for the dielectric porcelain of the present invention, oxides, carbonates, hydroxides of the above-mentioned elements,
Any of alkoxide and the like may be used.

As a method of mixing the raw material powder, a wet mixing method of mixing with water or an organic solvent in a ball mill,
A dry mixing method of mixing with a mixer or the like or mixing in a ball mill without using a solvent is generally used, and any of them may be used. Further, an alkoxide method or a coprecipitation method may be used depending on a starting material. That is, various known techniques that can be employed when manufacturing dielectric porcelain can be employed. It is desirable to use a solvent for mixing in a ball mill because the process is relatively complicated and it is easy to obtain a homogeneous mixture.In addition, a dispersant is used to improve the dispersibility of the powder, and the pH is adjusted. May go.

The mixture does not have to be calcined, but calcining can shorten the calcining time. The calcination temperature varies depending on the composition, but is usually about 800 to 1250 ° C. for about 2 to 8 hours.

As a method of pulverizing the calcined product or the mixture, there is a method using a ball mill, a high-speed rotary pulverizer, a medium stirring mill, an air current pulverizer, or the like, and any of them may be used. The molding is usually performed into a desired shape by press molding.
Although not particularly limited, the pressure in press molding is usually in the range of about 0.5 to 1.5 ton / cm ² .

The firing is not particularly limited because it varies depending on the composition, the size of the molded product, and the like, but is usually performed at about 400 to 700 ° C. for about 1 to 100 hours to remove the binder. , 1300-16
It is desirable to bake at about 50 ° C. for about 1 to 100 hours.

Hereinafter, the present invention will be further described with reference to specific examples. Example 1 As starting materials, chemically high-purity ZrO ₂ , TiO ₂ , M
gO, CoO, ZnO, NiO, Nb ₂ O ₅ , MnCO
Using No. ₃ , these were weighed to have a predetermined composition, and were wet-mixed with ethanol using a ball mill. The volume ratio of powder to ethanol is about 2: 3. The mixture was taken out of the ball mill, dried, and then calcined in air at 1000 ° C. for 2 hours. The calcined product was wet-pulverized in the ball mill together with ethanol. After the pulverized slurry was taken out of the ball mill and dried, 8% by weight of a polyvinyl alcohol solution having a concentration of 6% as a binder was added to the powder, mixed and homogenized, and sized through a 32 mesh sieve. The sized powder is 7 mm in diameter at a molding pressure of 1.3 ton / cm ² using a mold and a hydraulic press.
It was formed into a disk having a thickness of about 3 mm. After placing the molded body in a high-purity magnesia pod and holding it in the air at a temperature of 600 ° C. for 4 hours to perform binder-out, it is held in the air at a temperature of 1500 ° C. for 24 hours and firing. , Quenching (outside furnace and air cooling) or 1000
C. (at a cooling rate of 20.degree. C./hr) to obtain dielectric porcelain.

The resonance frequency of the obtained dielectric ceramic was determined from the measurement by the conductor cavity type dielectric cylinder resonator method. The temperature coefficient (τ _f ) of the resonance frequency was determined in the range of −25 ° C. to 85 ° C.

The composition of the dielectric ceramic thus produced is shown in Table 1 and the cooling conditions after firing and the temperature coefficient of the resonance frequency (ppm / ° C.) are shown in Table 2. In Tables 1 and 2, those marked with * are comparative examples.

[0034]

[Table 1]

[0035]

[Table 2]

As is clear from the results shown in Table 2,
In the dielectric ceramics of Sample Nos. 3 to 10, the fluctuation of the temperature coefficient of the resonance frequency due to the heat history at the time of firing the ZrTiO ₄ and ZrO ₂ —SnO ₂ —TiO ₂ ceramics is reduced. For sample numbers 3 to 10, Al ₂ O ₃ , Si
O ₂ , BaCO ₃ , SrCO ₃ , La ₂ O ₃ , Sm ₂ O
The same effect was confirmed for dielectric ceramics to which at least one of ₃ was added at 0.5 mol%. In addition, other components may be added as long as the object of the present invention is not impaired.

According to the configuration of the above item (1) of the present invention, Zr
It is understood that it is possible to reduce the variation of the temperature coefficient of resonant frequency due to TiO ₄ based and ZrO ₂ -SnO ₂ -TiO ₂ based heat history during sintering porcelain. Example 2 As starting materials, chemically pure ZrO ₂ , TiO ₂ , M
gO, CoO, ZnO, NiO, MnCO ₃ , Nb ₂ O
Using No. ₅ , these were weighed to have a predetermined composition, and wet-mixed with ethanol using a ball mill. The volume ratio of powder to ethanol is about 2: 3. The mixture was taken out of the ball mill, dried and calcined in air at a temperature of 800 to 1250 ° C. for 2 to 8 hours. The calcined product was wet-pulverized in the ball mill together with ethanol. After taking out the pulverized slurry from the ball mill and drying, 8% by weight of a polyvinyl alcohol solution having a concentration of 6% as a binder is added to the powder, mixed and homogenized.
The mixture was sized through a 32-mesh sieve. The sized powder is molded using a mold and a hydraulic press at a molding pressure of 1.3 ton / cm ^2.
Into a disk having a diameter of 7 mm and a thickness of about 3 mm. The molded body is placed in a high-purity magnesia pod and kept in the air at a temperature of 400 ° C. to 700 ° C. for 4 to 8 hours to perform binder-out, and then in the air at 1300 ° C.
It was kept at a temperature of 1650 ° C. for 1 to 100 hours and fired to obtain a dielectric ceramic.

From the measurement of the obtained dielectric porcelain by the conductor cavity type dielectric cylinder resonator method, the resonance frequency and the unloaded Q (Q
_u ) value and relative permittivity (ε _r ) were determined. The temperature coefficient (τ _f ) of the resonance frequency was determined in the range of −25 ° C. to 85 ° C. The resonance frequency was in the range of 5-10 GHz.

The relative permittivity, the temperature coefficient of the resonance frequency (ppm / ° C.) and the no-load Q value thus obtained are shown in Tables 3 to 9. In Tables 3 to 9, those marked with * are comparative examples.

[0040]

[Table 3]

[0041]

[Table 4]

[0042]

[Table 5]

[0043]

[Table 6]

[0044]

[Table 7]

[0045]

[Table 8]

[0046]

[Table 9]

As is evident from the results shown in Tables 3 to 9, the dielectric ceramic compositions in the composition range described in the above item (2) of the present invention have a relative dielectric constant in a microwave frequency band. Has a high no-load Q value while maintaining a large value.

On the other hand, when x is larger than 0.60, the no-load Q value is remarkably low as in sample numbers 54 to 56 and sample number 123, and the object of the present invention cannot be achieved. Also, when x is smaller than 0.10, the no-load Q value is low as in sample numbers 60 and 61 and sample number 126, and the object of the present invention cannot be achieved.

When y is larger than 0.60, the no-load Q value is remarkably lowered as shown in Sample Nos. 26 to 29 and Sample No. 116, and Sample Nos. 15 to 18 are obtained even when y is smaller than 0.20. And the no-load Q value is too low as in sample No. 114, so that the object of the present invention cannot be achieved.

When z is larger than 0.70, the no-load Q value is reduced as shown in Sample Nos. 30 to 33 and Sample No. 117, and when z is smaller than 0.01, Sample No. 36 is obtained.
As described above, the temperature coefficient of the resonance frequency becomes extremely large and the no-load Q value becomes extremely low, so that the object of the present invention cannot be achieved.

The unloaded Q value can be improved by making w larger than 0. However, when w is larger than 1.50, Sample Nos. 93 to 96 and Sample No. 13
3, the no-load Q value is degraded. However, even with sample number 133, the characteristics were good as compared with the conventional dielectric porcelain.

A (where A is Mg, Co, Z
When at least one element selected from n, Ni, and Mn is used, and a powder obtained by calcining an oxide of Nb at 800 to 1200 ° C. in advance is used as a raw material powder, the no-load Q value can be improved. It was confirmed within the composition range of this example.

Also, by adding a small amount of additives,
Can be improved, and the characteristics are not greatly deteriorated.
It was confirmed within the composition range. For example, Al
_TwoO _ThreeOf 0.08 wt. %, The baking temperature is about
50 ℃ lower, SiO_TwoOf 0.08 wt. % Added
The co-firing temperature drops by about 25 ° C.
Did not change much. In addition, BaCO_Three, SrCO
_Three, La_TwoO_Three, Sm _TwoO_Three0.1 at least one of
The characteristics of the dielectric porcelain to which mol% was added changed significantly.
Did not convert. In addition, other components other than this
It may be added as long as the purpose of the light is not impaired.

Example 3 As starting materials, chemically high-purity ZrO ₂ , TiO ₂ , M
gO, CoO, ZnO, NiO, MnCO ₃ , Ta ₂ O
Using No. ₅ , these were weighed to have a predetermined composition, and wet-mixed with ethanol using a ball mill. The volume ratio of powder to ethanol is about 2: 3. The mixture was taken out of the ball mill, dried and calcined in air at a temperature of 900 to 1250 ° C. for 2 to 8 hours. The calcined product was wet-pulverized in the ball mill together with ethanol. After the pulverized slurry was taken out of the ball mill and dried, 8% by weight of a polyvinyl alcohol solution having a concentration of 6% as a binder was added to the powder, mixed and homogenized.
The particles were sieved through a mesh sieve. The sized powder was molded into a disk having a diameter of 7 mm and a thickness of about 3 mm at a molding pressure of 1.3 ton / cm ² using a mold and a hydraulic press. Place the compact in a high-purity magnesia pod and place it in air for 40 minutes.
After the binder-out was performed at a temperature of 0 ° C. to 700 ° C. for 4 to 8 hours, the temperature was reduced to 1300 ° C. to 16 ° C. in air.
The resultant was held at a temperature of 50 ° C. for 1 to 100 hours and fired to obtain a dielectric ceramic.

From the measurement of the obtained dielectric porcelain by the conductor cavity type dielectric cylinder resonator method, the resonance frequency and the no-load Q
The (Q _u ) value and the relative permittivity (ε _r ) were determined. The temperature coefficient (τ _f ) of the resonance frequency was determined in the range of −25 ° C. to 85 ° C. The resonance frequency was in the range of 5-10 GHz.

The relative permittivity, the temperature coefficient of the resonance frequency (ppm / ° C.) and the no-load Q value thus obtained are shown in Tables 10 to 11. (Table 10) to (Table 1)
Those marked with * in 1) are comparative examples outside the scope of the present invention.

[0057]

[Table 10]

[0058]

[Table 11]

As is clear from the results shown in Tables 10 to 11, the dielectric ceramic composition of the present invention within the composition range of the above item (3) has a large relative dielectric constant in a microwave frequency band. It has a high no-load Q value while keeping the value.

When x is larger than 0.60, the no-load Q value becomes extremely low as in sample No. 152, so that the object of the present invention cannot be achieved. Also, x
Is smaller than 0.10, the unloaded Q value is low as in Sample No. 155, so that the object of the present invention cannot be achieved.

When y is larger than 0.60, the no-load Q value is remarkably reduced as in sample No. 138, and when y is smaller than 0.10.
As described above, the unloaded Q value becomes too low, so that the object of the present invention cannot be achieved.

When z is larger than 0.80, the no-load Q value is low as in sample No. 139, and when z is less than 0.01, the no-load Q value is extremely low as in sample No. 141. However, the object of the present invention cannot be achieved.

The unloaded Q value can be improved by making w larger than 0. However, when w is larger than 1.00, the unloaded Q value becomes extremely low as in sample number 168. However, the object of the present invention cannot be achieved.

A (where A is Mg, Co, Z
When at least one element selected from the group consisting of n, Ni, and Mn is used, and a powder obtained by calcining an oxide of Ta at 800 to 1200 ° C. in advance is used as a raw material powder, the no-load Q value can be improved. It was confirmed within the composition range of this example.

Further, sintering properties can be obtained by adding a small amount of additives.
Can be improved, and the characteristics are not greatly deteriorated.
It was confirmed within the composition range. For example, if the sample number 151
_TwoO _ThreeOf 0.08 wt. %, The baking temperature is about
100 ℃ lower, SiO_TwoOf 0.08 wt. % Added
In this case, the firing temperature drops by about 50 ° C
Did not deteriorate significantly. In addition, BaCO_Three, SrC
O_Three, La_TwoO_Three, Sm_TwoO_ThreeAt least one of.
The characteristics are large even for dielectric porcelain to which 1 mol% is added.
Did not deteriorate. In addition, other components
It may be added as long as the object of the invention is not impaired.

From the powder X-ray diffraction of the dielectric porcelain within the composition range of Examples 1 to 3 of the present invention, a ZrTiO ₄ phase or a crystallographically ZrTiO ₄ phase was confirmed.
Furthermore, ZrTiO ₄ phase or crystallographically ZrTiO _4
The composition analysis of a fractured surface and a polished surface of a dielectric ceramic mainly composed of _four phases by a local X-ray diffractometer shows that Zr, Ti, A, B (where A is Mg) , C
o, Zn, Ni, and Mn, and B represents at least one element selected from Nb and Ta). It was consistent with the composition ratio of other crystal grains constituting the main phase in the body porcelain. Further, it was confirmed that all the blended A and B components were present in a single grain.

Further, it was confirmed that the dielectric constant of the Zr, Ti, A, B components in a single grain is larger than that of the ZrTiO ₄ porcelain obtained under the same firing conditions. Was done. From these facts, ZrTiO ₄
It was confirmed that the ZrTiO ₄ phase was solid-solution substituted with the A and B components in a phase or crystallographically.

Such a dielectric porcelain has a particularly high no-load Q value, a large relative dielectric constant, excellent temperature stability of the resonance frequency, and a ratio a of the mole fraction of the component A and the component B described above.
When / b was 0.5 or more and 1.0 or less, the no-load Q value was further higher.

From the above results, the dielectric porcelain described in the above items (4) and (5) of the present invention has a high unloaded Q value while keeping the relative dielectric constant large in the microwave frequency band. However, it is recognized that the temperature stability of the resonance frequency is excellent.

Example 4 A chemically pure ZrO was used as a starting material._Two, TiO_Two, M
gO, CoO, ZnO, NiO, MnCO_Three, Nb_TwoO
_FiveThese are weighed to obtain the prescribed composition, and
The mixture was wet-mixed with ethanol using a Lumil. powder
The volume ratio between ethanol and ethanol is about 2: 3. This mixture
After taking out from the ball mill and drying, in air
Calcination was performed at a temperature of 900 to 1250 ° C. for 2 to 8 hours. Calcined
The product is wet-pulverized in the above ball mill together with ethanol.
did. Remove the ground slurry from the ball mill and dry
After that, a 6% concentration polyvinyl chloride as a binder for the powder
Add 10% by weight of alcohol solution and mix
And sieved through a 32 mesh sieve. Sized powder
Is a molding pressure of 1 ton / cm using a mold and a hydraulic press. ^Two
To form cylinders of 16mm, 35mm, 70mm in diameter
Was. The diameter: thickness of the compact was about 2: 1.
Place the compact in a high-purity magnesia pod
At 400 ° C to 700 ° C for 2 to 100 hours
After holding the binder out, in the air
Hold at a temperature of 1300 ° C to 1650 ° C for 1 to 100 hours
And fired to obtain a dielectric porcelain.

The obtained dielectric porcelain was plated with silver (with a thickness of 10 μm).
m) placed in the center of the copper cylindrical cavity
Electromagnetic waves transmitted from the antenna provided on the side of the cavity
Dielectric TE₀₁Dielectric material utilizing δ mode resonance
A shaker was configured. The inner dimensions of the copper cylindrical cavity are dielectric
The diameter and thickness of the porcelain are about 4 times each, and the thickness is 5m
m. Measurement by vector network analyzer
Resonance frequency and Q _uThe value was determined. In addition, diameter 16m
m, the resonance frequency is 2 to 5 GHz and 3
1 to 2.5 GHz for 5 mm, 0.6 to 70 mm
It was 1.5 GHz.

The resonance frequency (f) obtained as described above
And f × Qu values are shown in (Table 12) to (Table 13). In Tables 12 to 13, those marked with * are comparative examples outside the scope of the present invention.

[0073]

[Table 12]

[0074]

[Table 13]

As is clear from the results shown in Tables 12 and 13, TE ₀₁ described in the above item (7) of the present invention was used.
It has been found that a δ-mode dielectric resonator has a high unloaded Q factor in the microwave frequency band, and particularly has a significantly higher unloaded Q factor in a relatively low frequency band.

The volume of the dielectric ceramic at a resonance frequency of 0.8 GHz is, for example, ZrO ₂ —SnO ₂ —TiO.
Approximately 113 cc for ₂ series porcelain (ε _r = 37.0), Ba (Mg
_{About 1/3} Ta _2/3 ) O ₃ ceramic (ε _r = 24.0) is about 200
For example, the volume of sample number 177 of the present invention is about 83 cc. Since the volume of the TE ₀₁ [delta] -mode dielectric resonator comprising one corresponding to the volume of the dielectric ceramic, wherein the present invention (7) TE ₀₁ δ-mode dielectric resonator according to claim at a relatively low frequency range It becomes extremely small.
Further, since the dielectric ceramic is extremely small and lightweight as compared with the conventional one, there is an advantage that the raw material cost and the manufacturing cost of the dielectric resonator are reduced.

Example 5 As starting materials, chemically high-purity ZrO ₂ , TiO ₂ , M
gO, CoO, ZnO, NiO, MnCO ₃ , Ta ₂ O
Using No. ₅ , these were weighed to have a predetermined composition, and wet-mixed with ethanol using a ball mill. The volume ratio of powder to ethanol is about 2: 3. The mixture was taken out of the ball mill, dried and calcined in air at a temperature of 900 to 1250 ° C. for 2 to 8 hours. The calcined product was wet-pulverized in the ball mill together with ethanol. After the pulverized slurry was taken out of the ball mill and dried, 8% by weight of a polyvinyl alcohol solution having a concentration of 6% as a binder was added to the powder, mixed and homogenized.
The particles were sieved through a mesh sieve. The sized powder was molded into a disk having a diameter of 7 mm, 16 mm, 42 mm, and 70 mm at a molding pressure of 1.3 ton / cm ² using a mold and a hydraulic press. The diameter: thickness of the compact was about 2: 1. The molded body is placed in a high-purity magnesia pod, and is heated in air at a temperature of 1300 ° C. to 1650 ° C. for 1 to 10 minutes.
This was held for 0 hour and fired to obtain a dielectric porcelain. The obtained dielectric porcelain is placed in the center of a silver-plated (10 μm-thick) copper cylindrical cavity, and the TE ₀₁ δ mode resonance of the dielectric due to electromagnetic waves transmitted from an antenna provided on the side of the cavity is measured. The dielectric resonator used was constructed.

The inner diameter of the copper cylindrical cavity is about four times the diameter and thickness of the dielectric ceramic, and the thickness is 5 mm. The resonance frequency and the Qu value were obtained from the measurement by the vector network analyzer. In the case of a molded product having a diameter of 7 mm, the resonance frequency is 8 to 9 GHz and 16 mm.
3-4 GHz, 42 mm 1-2 GHz, 70 m
m was 0.6 to 0.9 GHz.

The resonance frequency (f) obtained as described above
And f × Qu values are shown in (Table 14). (Table 1
Those marked with * in 4) are comparative examples outside the scope of the present invention.

[0080]

[Table 14]

As is clear from the results shown in Table 14, the TE ₀₁ δ mode dielectric resonator according to the above mode (8) has a high unloaded Q value in a microwave frequency band, In particular, it has a remarkably high unloaded Q factor in a relatively low frequency band.

The volume of the dielectric ceramic at a resonance frequency of 0.8 GHz is, for example, ZrO ₂ —SnO ₂ —TiO
Approximately 113 cc for ₂ series porcelain (ε _r = 37.0), Ba (Mg
_{About 1/3} Ta _2/3 ) O ₃ ceramic (ε _r = 24.0) is about 200
cc, for example, the volume of sample number 211 of the present invention is about 98 cc. Since the volume of the TE ₀₁ [delta] -mode dielectric resonator comprising one corresponding to the volume of the dielectric ceramic, wherein the present invention (8) TE ₀₁ δ-mode dielectric resonator according to claim at a relatively low frequency range It becomes extremely small.
Further, since the dielectric ceramic is extremely small and lightweight as compared with the conventional one, there is an advantage that the raw material cost and the manufacturing cost of the dielectric resonator are reduced.

In the fourth and fifth embodiments, a cylindrical dielectric ceramic is used. However, the present invention is not limited to this. For example, a ring-shaped dielectric ceramic may be used. That a TE ₀₁ δ-mode dielectric resonator having an equivalent or higher unloaded Q factor can be constructed,
The present inventors have confirmed.

As shown in the first embodiment, Z
r and Ti components, and {Mg, Co, Zn, Ni, Mn}
At least one component selected from the group consisting of:
The dielectric porcelain mainly composed of a composite oxide with at least one component selected from the group (B) consisting of {Nb, Ta} is obtained by firing ZrTiO ₄ and ZrO ₂ —SnO ₂ —TiO ₂ porcelain. Since the fluctuation of the temperature coefficient of the resonance frequency due to the heat history at the time can be reduced, the TE ₀₁ δ-mode dielectric resonator made of such a dielectric porcelain, that is, the TE according to the above item (6) of the present invention. ₀₁ δ mode dielectric resonators are useful.

Further, from the powder X-ray diffraction of the dielectric ceramics in Examples 1 to 5 of the present invention, a ZrTiO ₄ phase or a crystallographically ZrTiO ₄ phase was confirmed. Further, the composition analysis of a fractured surface and a polished surface of a dielectric ceramic mainly composed of a ZrTiO ₄ phase or a crystallographically ZrTiO ₄ phase by local X-ray diffractometer shows that Zr, Ti, A, B (where A is Mg, Co,
At least one element selected from the group consisting of Zn, Ni, and Mn, and B represents at least one element selected from the group consisting of Nb and Ta). Was consistent with the composition ratio of other crystal grains constituting the main phase in the same dielectric ceramic. Further, it was confirmed that all the blended A and B components were present in a single grain.

Further, it was confirmed that the dielectric constant of the Zr, Ti, A, and B components in a single grain is larger than that of the ZrTiO ₄ porcelain obtained under the same firing conditions. Was done. From these facts, ZrTiO ₄
It was confirmed that the ZrTiO ₄ phase was solid-solution substituted with the A and B components in a phase or crystallographically.

Such a dielectric porcelain has a particularly high no-load Q value, a large relative dielectric constant, excellent temperature stability of the resonance frequency, and a ratio a of the mole fraction of the component A and the component B described above.
When / b was 0.5 or more and 1.0 or less, the no-load Q value was further higher. That is, the TE ₀₁ δ-mode dielectric resonator according to the above (9) and (10) of the present invention comprising such a dielectric porcelain has a high relative dielectric constant in a microwave frequency band. It has the advantage of having a high no-load Q value and excellent temperature stability of the resonance frequency.

[0088]

According to the constitution of the dielectric porcelain and the porcelain composition according to the present invention, both Zr and Ti components and ｛Mg, C
o, Zn, Ni, Mn｝
Group consisting of at least one kind of component and {Nb, Ta} (B)
From a composite oxide with at least one component selected from
The conventional ZrTiO ₄
Systems and ZrO ₂ -SnO ₂ -TiO ₂ system porcelain have
In addition, the temperature coefficient of the resonance frequency fluctuates due to the heat history during firing.
Problem can be reduced. Further, the unloaded Q value is high, and the temperature coefficient of the resonance frequency can be arbitrarily changed without lowering the relative permittivity.

Further, according to the configuration of the TE ₀₁ δ mode dielectric resonator according to the present invention, the TE ₀₁ δ mode dielectric resonator has a high no-load Q value in the frequency range of 0.8 to 5 GHz, and has a small TE ₀₁ δ.
A mode dielectric resonator can be realized.

The dielectric porcelain and the porcelain composition according to the present invention in which the Nb element is used can be a less expensive dielectric porcelain and porcelain composition.

Claims (10)

(57) [Claims] 1. Zr and Ti components and ｛Mg, Co, Z
n, Ni, at least a one component selected from the group consisting of Mn} (A), a composite oxide of {Nb, at least one component selected from the group consisting of Ta} (B) induced < br /> Electric porcelain. 2. A composition formula of xZrO ₂ -yTiO ₂ -zA
_{When represented by (1 + w) / 3} Nb _{(2-w) / 3} O ₂ , the symbol A is at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} And x, y,
A dielectric porcelain composition in which z and w are in the ranges shown by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following). (Equation 1) 3. A composition formula of xZrO ₂ -yTiO ₂ -zA
_{When represented by (1 + w) / 3} Ta _{(2-w) / 3} O ₂ , the symbol A is at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} And x, y,
A dielectric porcelain composition in which z and w are in the ranges shown by the following formulas (however, x, y, and z are mole fractions, and w is a numerical value represented by the following). (Equation 2) 4. At least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} and {N
b, dielectric ceramic according to claim 1 containing as a main component at least ZrTiO ₄ phase one component is dissolved substituted or crystallographically ZrTiO ₄ phase selected from the group (B) consisting of Ta} . 5. At least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} and {N
b, Ta}, a ZrTiO ₄ phase in which at least one component selected from the group (B) selected from the group consisting of solid solution substitution or a crystallographically ZrTiO ₄ phase is the main component, and a / b (the symbol a And b represent the sum of the mole fractions of the components of the groups (A) and (B), respectively) from 0.5 to 1.0. 6. Both Zr and Ti components and ｛Mg, Co, Z
n, Ni, at least a one component selected from the group consisting of Mn} (A), a composite oxide of {Nb, at least one component selected from the group consisting of Ta} (B) induced < A TE ₀₁ δ mode dielectric resonator made of an electric porcelain. 7. A composition formula of xZrO ₂ -yTiO ₂ -zA
_{When represented by (1 + w) / 3} Nb _{(2-w) / 3} O ₂ , the symbol A is at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} And x, y,
TE ₀₁ δ-mode dielectric resonance composed of a dielectric porcelain in which z and w are in the ranges represented by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following). vessel. (Equation 3) 8. A composition formula of xZrO ₂ -yTiO ₂ -zA
_{When represented by (1 + w) / 3} Ta _{(2-w) / 3} O ₂ , the symbol A is at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} And x, y,
TE ₀₁ δ-mode dielectric resonance composed of a dielectric porcelain in which z and w are in the ranges represented by the following formulas (where x, y, and z are mole fractions, and w is a numerical value represented by the following). vessel. (Equation 4) 9. At least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} and {N
7. A dielectric ceramic comprising at least one component selected from the group (B) consisting of b, Ta｝ and a solid solution-substituted ZrTiO ₄ phase or a crystallographically ZrTiO ₄ phase as a main component. The described TE ₀₁ δ mode dielectric resonator. 10. At least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni, Mn} and {N
b, Ta}, a ZrTiO ₄ phase in which at least one component selected from the group (B) selected from the group consisting of solid solution substitution or a crystallographically ZrTiO ₄ phase is the main component, and a / b (the symbol a and b each said group (a) and (B) TE ₀₁ δ-mode according to claim 6 showing the sum of the mole fraction of component) is made of dielectric ceramic is 0.5 to 1.0 Dielectric resonator.