JP3193157B2 - Dielectric porcelain composition for low-temperature firing, dielectric resonator or dielectric filter obtained using the same, and methods for producing them - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric ceramic composition for low-temperature firing, and more particularly, to a low-temperature firing ceramic material suitably used for manufacturing a dielectric resonator having an inner conductor, such as a stripline type filter having a triplate structure. The present invention relates to a dielectric ceramic composition for high frequency which can be used. Further, the present invention provides a dielectric resonator obtained using such a dielectric ceramic composition or a dielectric filter comprising a plurality of the resonators,
Further, the present invention relates to an advantageous manufacturing method of the dielectric resonator or the dielectric filter.

[0002]

2. Description of the Related Art Today, coaxial dielectric filters using a high-permittivity porcelain composition are widely used in cellular phones, automobile telephones, and the like.
On the inner peripheral surface and outer peripheral surface of the cylindrical dielectric block, respectively, a plurality of coaxial resonators provided with an inner conductor and an outer conductor are coupled and configured, There is a limit to the miniaturization, and for this reason, a strip line type having a triplate structure in which a conductor is formed inside a dielectric is being studied. In this stripline type filter, conductors are arranged in a predetermined pattern in a plate-shaped dielectric and provided integrally, and a structure in which a plurality of resonators are formed is employed. (Thickness) can be reduced, so that the size can be reduced.

[0003] When a dielectric filter having an inner layer conductor such as a stripline type filter is manufactured, simultaneous firing of the inner layer conductor and the dielectric ceramic composition is required. Since the composition has a very high firing temperature, the composition is restricted by conductor materials that can be used as the inner layer conductor, and the composition has a low conduction resistance.
It was difficult to use g-based materials. For example, to use an Ag-Pd-based alloy or an Ag-Pt-based alloy as the inner layer conductor, the firing temperature of the dielectric ceramic composition is 1000 ° C.
In particular, in order to use Ag having a low conduction resistance alone, the firing temperature of the dielectric ceramic composition should be 90
It must be around 0 ° C. Therefore, there is a need for a dielectric ceramic composition that can be sintered at such a low firing temperature and has excellent high-frequency characteristics.

[0004] On the other hand, various types of dielectric ceramic compositions have been conventionally proposed.
Ba-Ti-RE-Bi-based oxide (RE: rare earth metal)
The dielectric ceramic composition composed of
It is also known as a material having a large no-load Q and a small temperature coefficient of the resonance frequency.
No. 107 and Japanese Unexamined Patent Publication No. 1-275466, etc. attempt to improve the relative dielectric constant and the temperature coefficient of the resonance frequency by further introducing SrO into such a composition system. In the dielectric porcelain composition,
In any case, there is a problem that the firing temperature is as high as 1300 ° C. to 1400 ° C. Therefore, attempts have been made to lower the firing temperature by adding a Pb oxide or the like.

For example, in US Pat. No. 3,811,937, a calcined mixture of barium oxide, titanium oxide, and rare earth oxide is added to CdO—PbO—Bi ₂ O _3.
A composition comprising 8 to 30% by weight of a base glass has been disclosed.
The firing is performed at a temperature of about 1150C. Also, in Japanese Patent Application Laid-Open No. Sho 59-214105, Ba
For an O—TiO ₂ —Nd ₂ O ₃ based composition, PbO,
By mixing the powders of Bi ₂ O ₃ , SiO ₂ and ZnO,
Firing at a temperature between 1050 ° C and 1150 ° C has been shown. Further, Japanese Patent Application Laid-Open No. Sho 60-124306 discloses that BaTiO ₃ —Nd ₂ O ₃ —TiO ₂ —Bi ₂ O
Against ₃ based _{compositions, Pb 3 O 4, B 2} O 3, SiO
₂ , a dielectric porcelain composition comprising a predetermined amount of each of ZnO is disclosed.
It has been revealed that firing can be performed at a firing temperature of Furthermore, Japanese Patent Application Laid-Open No. 2-44609 discloses BaTiO
_{3, Nd 2 O 3, TiO} 2, Bi 2 O 3, and Pb ₃ O
The composition consisting of _{4, 2CaO · 3B 2 O 3} , S
iO _2, and the dielectric ceramic composition obtained by adding ZnO is shown, it is clear that sintered at a firing temperature of from 1,000 to 1,050 ° C..

However, even in these conventional dielectric ceramic compositions which can be fired at a low temperature, the firing temperature is still as high as about 1000 ° C. or higher, and mainly Ag or Ag having a low conduction resistance is mainly used. Cannot be used as the internal conductor. For this reason, the content of Pd having a large conduction resistance is increased, and Ag-P
The fact is that only d-based alloys can be used. Moreover, in these conventional dielectric ceramic compositions for low-temperature firing, since a large amount of Pb oxide is added, there is a problem in handling in view of the toxicity of Pb oxide. there were.

Several prior art techniques for reducing the firing temperature of the dielectric ceramic composition to about 1000 ° C. are known, but the melting point of Ag is 962 ° C. or less, preferably 95%.
A technique for enabling sintering at 0 ° C. or less, more preferably around 900 ° C., has not yet been known.

[0008]

The present invention has been made in view of the above circumstances, and has as its object to have a high relative dielectric constant, a large unloaded Q, and a high resonance frequency. 962 to give a dielectric ceramic with a small temperature coefficient
At a sintering temperature of not more than 900 ° C. (melting point of Ag), preferably 900 ° C.
Sintering is possible at a sintering temperature of about ℃, and a large amount of Pb
An object of the present invention is to provide a dielectric porcelain composition for low-temperature sintering which does not need to contain an oxide. Another object of the present invention is to provide a dielectric resonator obtained by using such a dielectric porcelain composition or a dielectric filter comprising a plurality of such resonators, and furthermore, a dielectric filter comprising the same. It is to provide an advantageous method of manufacturing a resonator or a dielectric filter.

In order to solve such a problem, the present inventors have made various studies and found that BaO-SrO-C
against _{aO-TiO 2 -RE 2 O 3} -Bi 2 O 3 based dielectric ceramic composition, a predetermined amount of B ₂ O ₃ powder, or B ₂
It has been found that by adding a predetermined amount of each of ZnO and SiO ₂ together with the O ₃ powder, the firing temperature can be advantageously lowered while ensuring its excellent properties.

[0010]

That is, the present invention has been completed based on such findings, and the features thereof are as follows.
General formula: x [(1-ab) BaO.aSrO.bCa
O] · yTiO ₂ · z _{[(1-c) RE 2 O} 3 · cBi
₂ O ₃ ] (where RE represents a rare earth metal), and x, y, z and a, b, c in the general formula are
The following expressions, respectively: 0.10 ≦ x ≦ 0.20, 0.60 ≦
y ≦ 0.75, 0.10 ≦ z ≦ 0.25, x + y + z =
1,0 ≦ a ≦ 0.40, 0 ≦ b ≦ 0.20, and 0 ≦ c
≦ 0.30, a composition comprising barium oxide, strontium oxide, calcium oxide, titanium oxide, rare earth oxide, and bismuth oxide as a main component, and 100 parts by weight of the main component composition against it, there as an auxiliary component, a B ₂ O ₃ powder in low temperature fired dielectric ceramic composition comprising brought formulated in proportions of 0.1 to 7.5 parts by weight.

The present invention relates to a compound represented by the general formula: x [(1-a-
b) BaO · aSrO · bCaO] · yTiO ₂ · z
[(1-c) RE ₂ O ₃ .cBi ₂ O ₃ ] (provided that RE
Represents a rare earth metal), and x, y, z and a, b, c in the general formula are each represented by the following formula:
10 ≦ x ≦ 0.20, 0.60 ≦ y ≦ 0.75, 0.1
0 ≦ z ≦ 0.25, x + y + z = 1, 0 ≦ a ≦ 0.4
A composition comprising barium oxide, strontium oxide, calcium oxide, titanium oxide, rare earth oxide, and bismuth oxide, which is configured to satisfy 0, 0 ≦ b ≦ 0.20, and 0 ≦ c ≦ 0.30. As a main component, 100 parts by weight of the main component composition, as an auxiliary component, B
₂ O ₃ powder is added in a ratio of 0.1 to 7.5 parts by weight, and further, at least one of ZnO powder up to 8.0 parts by weight and SiO ₂ powder up to 3.0 parts by weight is blended. The dielectric ceramic composition for low-temperature firing described above is also characterized.

In the present invention, when producing such a dielectric ceramic composition for low-temperature firing, the raw material composition for providing the main component composition is calcined at a temperature of 1050 ° C. or higher, and then The obtained calcined material is finely pulverized so that the average particle size is 0.8 μm or less, and then the powders of the sub-components B ₂ O ₃ , ZnO, and SiO ₂ are blended to obtain the low-temperature calcined material. The method of producing the dielectric ceramic composition is advantageously employed. By adopting such a production process, the decrease in the firing temperature of the dielectric ceramic composition is remarkably promoted, and the relative dielectric constant is further reduced. An increase in the rate and an increase in the no-load Q can also be advantageously achieved.

Further, according to the present invention, there is provided a dielectric resonator having a dielectric pattern and a conductor pattern formed in the dielectric ceramic by co-firing with the dielectric ceramic, or a dielectric comprising the resonator. In the body filter, the dielectric porcelain is composed of the dielectric porcelain composition as described above, that is, a dielectric porcelain obtained by firing the dielectric porcelain composition according to claim 1 or 2. On the other hand, the conductor pattern
The present invention also provides a dielectric resonator or a dielectric filter including the resonator, wherein the dielectric is formed of Ag alone or an alloy material containing Ag as a main component.

Further, the present invention provides a method for manufacturing a dielectric resonator having a dielectric ceramic and a conductor pattern provided in the dielectric ceramic or a dielectric filter comprising the resonator. 2. The method of claim 1 wherein said porcelain is provided.
Alternatively, a conductor layer made of Ag alone or an alloy material containing Ag as a main component, which gives the conductor pattern, is formed on a molded body made of the dielectric ceramic composition according to claim 2 or a calcined product thereof. The invention also provides a method for manufacturing a dielectric resonator or a dielectric filter comprising the resonator, wherein the dielectric resonator is provided and co-fired.

[0015]

[Specific constitution] By the way, in this dielectric ceramic composition, x [(1-ab) BaO.aSrO.bCa
O] means that part of BaO, one of the main components, is SrO and / or
Or CaO.
If the total content of aO, SrO, and CaO is less than 10 mol% (x <0.10), there is a problem that the relative dielectric constant of the obtained dielectric ceramic becomes low.
If it exceeds mol% (x> 0.20), there arises a problem that the temperature coefficient of the resonance frequency becomes too large.

The partial substitution of BaO is carried out with at least one of SrO and CaO.
Is replaced with SrO, the unloaded Q can be improved and the temperature coefficient of the resonance frequency can be reduced while maintaining a high dielectric constant. However, if the substitution ratio is more than 0.40 (a> 0.40), there arises a problem that both the dielectric constant and the no-load Q deteriorate. When a part of BaO is replaced by CaO, the temperature coefficient of the resonance frequency can be increased while maintaining a high dielectric constant and no-load Q.
When it exceeds 20 (b> 0.20), the problem that the no-load Q is rapidly deteriorated is caused. Therefore, these Sr
By adding O and CaO, control of the temperature coefficient of the resonance frequency is advantageously realized.

On the other hand, when the content of TiO ₂ is less than 60 mol% (y <0.60), sintering becomes difficult and a dense sintered body cannot be obtained. On the other hand, when it exceeds 75 mol% (y> 0.7
5) There is a problem that the temperature coefficient of the resonance frequency becomes too large in the positive direction.

Further, regarding the total amount of RE ₂ O ₃ and Bi ₂ O ₃ , in other words, [(1-c) RE ₂ O ₃ · cBi
The value of the ₂ O _3], when the content of the sum is less than 10 mole% (z <0.10), the temperature coefficient of resonant frequency becomes too positive large, whereas, the 25 mole% If it exceeds (z> 0.25), there arises a problem that the sinterability is poor and the relative dielectric constant is reduced.

In the present invention, RE (rare earth metal) in RE ₂ O ₃ includes Nd, Sm, La, C
e, Pr, etc. Among them, Nd or Nd or Sm and / or La is preferably used in combination with Nd. N
When using Sm and / or La in combination with d, the temperature coefficient can be controlled while maintaining a high dielectric constant and no-load Q. However, when such Sm and / or La are combined, the ratio of Sm or La to the entire RE is 20 mol%.
It is desirable that the temperature be less than or equal to the above value. If the temperature exceeds the value, there arises a problem that the temperature coefficient of the resonance frequency greatly changes negatively or positively. In the case where Ce or Pr is used as RE, it is introduced after being converted into trivalent atoms.

Further, when RE ₂ O ₃ is replaced with Bi ₂ O ₃ , the relative dielectric constant is increased, and the temperature coefficient of the resonance frequency can be reduced. In particular, in order to obtain a sufficient substitution effect by Bi ₂ O ₃ , 5 mol% or more (c ≧
0.05) is desirable. However, BiO ₂
It reaches the substitution amount more than 15 to 20 mole percent of, and in the temperature coefficient begins to increase, also as the substitution amount of Bi ₂ O ₃ increases, since the unloaded Q decreases, Bi ₂ O
The substitution amount of ₃ is practically 30 mol% or less (c ≦ 0.3
0) is appropriate.

The present invention comprises a porcelain composition composed of barium oxide, strontium oxide, calcium oxide, titanium oxide, rare earth oxide and bismuth oxide at the above-mentioned ratios as a main component. As described later, a predetermined main component is added to such a main component composition. However, the improvement of no-load Q and the resonance For the purpose of correcting the temperature coefficient of frequency, aluminum oxide, iron oxide, manganese oxide, chromium oxide, zinc oxide,
Addition of a metal oxide such as tin oxide or zirconium oxide may be used at all.

In addition, B ₂ O added as an auxiliary component to the main component porcelain composition according to the present invention as described above.
₃ powder or B ₂ O ₃ powder and ZnO and / or S
Each powder of iO ₂ contains 0.1 to 7.5 parts by weight of boron oxide (B ₂ O ₃ ) per 100 parts by weight of the main component porcelain composition, and further contains zinc oxide (Zn) together with the boron oxide.
O) is from 0 to 8.0 parts by weight and / or silicon oxide (SiO
₂ ) must be used at a ratio of 0 to 3.0 parts by weight.

If the amount of B ₂ O ₃ added is less than 0.1 part by weight, the firing temperature of the dielectric ceramic composition may increase. On the other hand, if the amount exceeds 7.5 parts by weight. This causes a problem that the no-load Q becomes small.
Further, ZnO can improve the relative dielectric constant by its addition. However, when the addition amount exceeds 8.0 parts by weight, the unloaded Q of the target dielectric ceramic composition can be improved.
This causes a problem that the size becomes smaller. Further, the addition of SiO ₂ can improve the no-load Q, but when the addition amount exceeds 3.0 parts by weight, vitrification becomes difficult, and in addition, the purpose is improved. This is because this causes a problem that the firing temperature of the dielectric ceramic composition becomes high. Note that such B ₂ O ₃ , ZnO,
The preferred range of each powder of SiO ₂ is B ₂ O
₃ 0.5 to 3.0 parts by weight of powder, 0.5 to ZnO powder
5.0 parts by weight, SiO ₂ is 0.5 to 1.0 parts by weight.

In particular, in the present invention, the B ₂ O ₃ component is
The reason for adding as a single component (powder) instead of synthesizing it with other additional components to form a compound is that B ₂ O ₃ alone has a melting point as low as about 450 ° C. and has a great effect of lowering the firing temperature. is there. The B ₂ O ₃ powder includes B
H ₃ B which gives B ₂ O ₃ in addition to the powder of ₂ O ₃ itself
It is also possible to use O ₃ (boric acid) powder. This is because H ₃ BO ₃ changes to B ₂ O ₃ powder at around 300 ° C. In contrast, for example, ZnO and B ₂ O
_When the compound of No. ₃ is used, its melting point is 961 ° C. (ZnO
(B ₂ O ₃ ) or higher, which makes it difficult to sufficiently lower the firing temperature.

Further, to the B ₂ O ₃ powder, a ZnO component and a SiO ₂ component are also added as individual powders. In particular, compounds containing boron oxide such as ZnO—B ₂ O ₃ , for example, ZnO.B ₂ O ₃ , 5ZnO.2B
Addition in the form of ₂ O ₃ etc. must be avoided. However, when added in the form of a compound, the above-mentioned B ₂ O ₃
This is because not only the effect of adding powder alone cannot be obtained, but also the effect of adding the above-mentioned ZnO and SiO ₂ components becomes small. Also, the ZnO component, after firing,
This is because the compound does not form a compound with the B ₂ O ₃ component or the SiO ₂ component, and as it is understood from the fact that it coexists with TiO ₂ , the function as a single component is considered important.

The dielectric porcelain composition according to the present invention is different from the aforementioned main component porcelain composition in that
₂ O ₃ powder, or B ₂ O _3, ZnO, but is manufactured by allowed blended powders of SiO ₂ as subcomponent, such subcomponent serving B ₂ O _3, ZnO, in the formulation of SiO ₂ powder Prior to this, the above-mentioned main component porcelain composition is prepared by calcining and pulverizing the raw material composition giving the composition. When a calcination temperature of 900 ° C. or more is employed for the calcination, a decrease in the calcination temperature of the dielectric ceramic composition, an increase in the relative dielectric constant, and an increase in the no-load Q accompanying the increase in the calcination temperature are recognized. It is done. In particular, at a calcination temperature of 1050 ° C. or more, the effect is remarkable.
The calcination is performed at a temperature of 050 ° C. or higher. However, if the calcining temperature exceeds 1350 ° C., the calcined material hardens significantly after calcining, which causes a problem in handling. Therefore, preferably, the calcining temperature of 1100 ° C. to 1300 ° C. is advantageously employed. Becomes

When the calcined material obtained by calcining in this manner is pulverized, the lower the average particle size of the pulverized material, the more the decrease in the firing temperature of the dielectric ceramic composition is promoted, and It is possible to increase the permittivity and the unloaded Q. Therefore, in the present invention, 0.8
The calcined product is pulverized so as to have an average particle size of not more than μm. However, when the average particle size of the calcined and pulverized product is smaller than 0.1 μm, the moldability of the obtained dielectric porcelain composition is reduced, and for example, it is difficult to form a tape by a normal doctor blade method or the like. It is desirable to control the average particle size of the calcined and pulverized product to about 0.1 to 0.8 μm. In addition, the particle diameter of such a fine pulverized product is generally measured by using a laser diffraction scattering method.

[0028]

EXAMPLES Hereinafter, some examples of the present invention will be described to clarify the present invention more specifically. However, the present invention does not impose any restrictions due to the description of such examples. Needless to say, it is not what we receive. In addition, various changes, modifications, improvements, and the like can be made to the present invention based on the knowledge of those skilled in the art without departing from the spirit of the present invention, in addition to the examples described below. Should be understood.

Example 1 High purity barium carbonate, strontium carbonate, calcium carbonate, titanium oxide, neodymium oxide, samarium oxide,
Using lanthanum oxide and bismuth oxide, their components are:
Various types of x, y, z, RE, and
Each was weighed so as to give a, b, and c values, charged into a polyethylene pot together with zirconia cobblestone, added with pure water, and wet mixed. Then, the obtained mixture was taken out of the pot, dried, put into an alumina crucible, and calcined at a temperature of 1250 ° C. for 4 hours in an air atmosphere. Next, the calcined product is disintegrated, and again put together with zirconia cobblestone in a polyethylene pot, and pulverized until the average particle diameter measured using a laser diffraction scattering method becomes 0.8 μm or less. This was performed to obtain various calcined and pulverized products.

Next, 100 parts by weight of the various calcined and pulverized materials thus obtained were mixed with B ₂ O ₃ powder and Zn as auxiliary components.
Predetermined amount of O powder and SiO ₂ powder (amount shown in Table 1)
Were put together with zirconia cobblestone into a polyethylene pot, pure water was added, and wet-mixed. At that time, 1% by weight of PVA was added as a binder. After the obtained mixture was dried, the mixture was passed through a sieve with openings of 355 μm and granulated.

[0031] Thus various granulated powder obtained by using a press molding machine, surface pressure: 1 ton / molded at cm ^2, a disc-shaped test piece size of each 20 mm.phi × 15 mm ^t I got The obtained test pieces were fired in air at 900 ° C. for 2 hours to produce various dielectric ceramic samples. Furthermore, polishing the sample obtained by this firing to the size of the disc-shaped diameter of 16 mm × 8 mm ^t, respectively, to measure the dielectric properties. The relative permittivity (εr) and the no-load Q were measured by a parallel conductor plate type dielectric resonator method, and the temperature coefficient (τf) of the resonance frequency was measured in a range of −25 ° C. to + 75 ° C. The measurement frequency was 2 to 4 GHz. Table 2 shows the obtained results.

[0032]

[Table 1]

[0033]

[Table 2]

Example 2 The calcined and pulverized product obtained as No. 14 in Example 1 was used, and 100 parts by weight of the calcined and pulverized product were mixed with B ₂ O ₃ powder (external 1.
0 parts by weight), polyvinyl butyral (external 8 parts by weight),
A plasticizer and a deflocculant were put into an alumina pot together with zirconia cobblestone, and a mixed solution of toluene and isopropyl alcohol was further added and wet-mixed.

Next, the mixture was defoamed and formed into a green tape having a thickness of 250 μm by a doctor blade method. Then, a conductive pattern of a 900 MHz _Z- band two-stage bandpass filter was printed on the obtained green tape using a printing Ag paste. Next, 20 green tapes were heated at a temperature of 100 so as to sandwich the green tape on which the conductor pattern was printed.
The layers were laminated under the conditions of a temperature of 100 ° C. and a pressure of 100 kgf / cm ² . Then, after cutting the laminate, 900 ° C. in air.
By sintering at a temperature of 2 hours, a stripline type filter having a structure as shown in FIG. 1 was produced. In the stripline filter shown in FIG. 1, the dielectric substrate 16 has a three-layer structure, and is integrated by simultaneous firing with a conductor. A plurality of resonance electrodes 12, 12 are built in one layer of the dielectric substrate 16, and a pair of coupling electrodes 20, 20 are built in a different layer. On the other hand, an earth electrode 14 is provided on substantially the entire outer surface of the dielectric substrate 16, and a pair of input / output terminals is provided on a pair of opposing side surfaces in a state of being disconnected from the earth electrode 14. Terminal 1
8, 18 are provided. Then, the coupling electrodes 20, 20 are extended, and the end of the extended portion 20a is extended to the outer surface of the dielectric substrate 16, so that the input / output terminal 18 on the outer surface and the inner coupling are formed. That is, the electrodes 20 are connected to each other.

The filter characteristics of the stripline type filter thus obtained were measured using a network analyzer. As a result, the center frequency was 900 MHz.
_Z , insertion loss: 1.5 dB.

[0037]

As is apparent from the above description, the dielectric porcelain composition according to the present invention comprises barium oxide (BaO),
Strontium oxide (SrO), calcium oxide (Ca
O), titanium oxide (TiO ₂ ), rare earth oxide (RE
₂ O ₃ ) and bismuth oxide (Bi ₂ O ₃ ) as main components, each of which is contained in a specific amount, and a predetermined amount of B ₂ O ₃ powder or ZnO, SiO ₂ together with B ₂ O ₃ powder
By containing a predetermined amount of each powder of
It is possible to sinter at a firing temperature of 962 ° C. (the melting point of Ag) or lower, preferably at a firing temperature of around 900 ° C.,
As a result, a dielectric filter such as a stripline type filter having an inner conductor made of Ag alone or an alloy material containing Ag as a main component having low conduction resistance can be advantageously manufactured. Body porcelain
It has the features of having a high relative dielectric constant, a large unloaded Q, and a small temperature coefficient of the resonance frequency.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a form of a laminated structure of a dielectric filter manufactured in Example 2.

[Explanation of symbols]

 12 Resonance electrode 14 Earth electrode 16 Dielectric substrate 18 Input / output terminal 20 Coupling electrode

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-3-290358 (JP, A) JP-A-2-44609 (JP, A) JP-A-60-124306 (JP, A) JP-A-63- 285150 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C04B 35/42-35/49 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. Sintering at a firing temperature of 962 ° C. or less
, Dielectric ceramic composition containing no Pb oxide
And having the general formula: x [(1-ab) BaO.aS
rO · bCaO] · yTiO ₂ · z [(1-c) RE ₂
O ₃ .cBi ₂ O ₃ ] (wherein RE represents a rare earth metal), and x, y, z and a, b, c in the general formula are each represented by the following formula: 0.10 ≦ x ≦ 0.2
0, 0.60 ≦ y ≦ 0.75, 0.10 ≦ z ≦ 0.2
5, x + y + z = 1, 0 ≦ a ≦ 0.40, 0 ≦ b ≦ 0.
20, and a composition composed of barium oxide, strontium oxide, calcium oxide, titanium oxide, rare earth oxide, and bismuth oxide, which is configured to satisfy 0 ≦ c ≦ 0.30. Thing 10
Relative to 0 parts by weight, as an auxiliary component, a B ₂ O ₃ powder 0.
A dielectric ceramic composition for low-temperature firing, wherein the dielectric ceramic composition is blended in an amount of 1 to 7.5 parts by weight. 2. Sintering at a firing temperature of 962 ° C. or lower.
, Dielectric ceramic composition containing no Pb oxide
And having the general formula: x [(1-ab) BaO.aS
rO · bCaO] · yTiO ₂ · z [(1-c) RE ₂
O ₃ .cBi ₂ O ₃ ] (wherein RE represents a rare earth metal), and x, y, z and a, b, c in the general formula are each represented by the following formula: 0.10 ≦ x ≦ 0.2
0, 0.60 ≦ y ≦ 0.75, 0.10 ≦ z ≦ 0.2
5, x + y + z = 1, 0 ≦ a ≦ 0.40, 0 ≦ b ≦ 0.
20, and a composition composed of barium oxide, strontium oxide, calcium oxide, titanium oxide, rare earth oxide, and bismuth oxide, which is configured to satisfy 0 ≦ c ≦ 0.30. Thing 10
Relative to 0 parts by weight, as an auxiliary component, a B ₂ O ₃ powder 0.
1 to 7.5 parts by weight, and additionally up to 8.0 parts by weight of ZnO powder and up to 3.0 parts by weight of SiO ₂
A dielectric ceramic composition for low-temperature firing, wherein at least one of the powders is blended. 3. A dielectric ceramic and a conductor pattern formed in the dielectric ceramic by co-firing with the dielectric ceramic.
2. A dielectric resonator having a resonator or a dielectric filter comprising said resonator, wherein said dielectric porcelain is made of said dielectric ceramic.
Alternatively, while the dielectric ceramic composition according to claim 2 is constituted by a dielectric ceramic obtained by firing, the conductor pattern is formed of Ag alone or an alloy material containing Ag as a main component. A dielectric resonator or a dielectric filter comprising the resonator. 4. When manufacturing a dielectric resonator having a dielectric ceramic and a conductor pattern provided in the dielectric ceramic or a dielectric filter comprising the resonator, the dielectric ceramic is provided. A molded body made of the dielectric ceramic composition according to claim 1 or 2, or a calcined product thereof, which is made of Ag alone or an alloy material mainly composed of Ag to give the conductor pattern. A method for manufacturing a dielectric resonator or a dielectric filter comprising the resonator, wherein a conductive layer to be formed is provided and co-fired.