JP2000272960A - Dielectric ceramic composition for microwave use, its production and electronic part for microwave use produced by using the dielectric ceramic composition for microwave use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric ceramic composition for microwave use having high Q-value and small τf and enabling the baking at a temperature as low as 1000 deg.C or below. SOLUTION: The objective composition is composed mainly of oxides of Al, Si and Sr, contains Al, Si and Sr in amounts of 10-60 wt.% in terms of Al2O3, 25-60 wt.% in terms of SiO2 and 7.5-50 wt.% in terms of SrO based on 100 wt.% of the sum of Al, Si, and Sr in terms of Al2O3 SiO2 and SrO and further contains 0.1-10 wt.% Bi in terms of Bi2O3 as an accessory ingredient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric porcelain composition used in a microwave region, and more particularly, to a high Q,
The present invention relates to a dielectric ceramic composition which has stable temperature characteristics and has a low-temperature sinterability that can be simultaneously fired with an internal electrode material such as silver or copper, a method for producing the same, and a microwave electronic component using the same.

[0002]

2. Description of the Related Art In recent years, with the development of communication technology using electromagnetic waves in the microwave range, such as automobile telephones, mobile telephones, and satellite broadcasting, there has been a demand for miniaturization of devices. For this purpose, it is necessary to reduce the size of individual components constituting the device.

[0003] Dielectric ceramic compositions are used in these microwave devices as materials for dielectric resonators, filters, multilayer inductors or multilayer capacitors, and high-frequency multilayer substrates obtained by combining these. If the size of the dielectric resonator uses the same resonance mode,
It is inversely proportional to the square root of the dielectric constant of the dielectric material. Therefore, in order to manufacture a small-sized dielectric resonator, a dielectric material having a high dielectric constant is required. Other characteristics required as a microwave dielectric material include a small dielectric loss tan δ (= 1 / Q) in the microwave region, that is, a large Q value, and a temperature coefficient τf of the resonance frequency. It must be as close to zero as possible.

Furthermore, dielectric resonators, filters, multilayer inductors, and internal electrodes of multilayer capacitors used in the microwave region must be made of a material having low resistance loss in the microwave band. Silver or copper
It is necessary to use a metal material having high conductivity such as gold. In addition, in order to reduce the size of these electronic components for microwaves, a multilayer electronic component obtained by simultaneously firing a multilayer structure of ceramics and internal electrodes has been attempted. Therefore, silver (melting point 961)
C.), copper (melting point 1083 ° C.), gold (melting point 1063 ° C.), and an electrode material having a low melting point, and co-firing with a dielectric material, the temperature of the dielectric material is 1000 ° C. or less, preferably 900 ° C. It must be a material that sinters at a temperature of not more than ℃.

[0005] As an example of a conventional dielectric material used in the microwave band, JP-A-8-325055 discloses an oxide of Al, Si, Pb, Na, K, Ca and Sr. In the porcelain composition, the composition ratio is Al
_{2 O 3 40~60%, SiO 2} 25~40%, Pb
O 5-15%, Na ₂ O 0.1-3%, K ₂ O1
A low-temperature fired porcelain composition comprising 3%, 1-6% CaO and 1-6% SrO is disclosed. According to this, 9
Low-temperature baking at about 00 ° C. is possible.

Another example of a dielectric material used in the conventional microwave band is disclosed in Japanese Patent Publication No. 6-74166.
No. 25-80% by weight of SiO ₂ , BaO, S
15 to 70% by weight of one or two of rO and B
Cr ₂ O as a main component consisting of 1.5 to 5% by weight of ₂ O _3
3 , a porcelain composition to which any one of CuO, NiO, Co ₂ O ₃ and Fe ₂ O ₃ is added, and when the additive is Cr ₂ O ₃ or CuO, 0.2 to 10% by weight %, And when the additives are NiO, Co ₂ O ₃ and Fe ₂ O ₃ , they are added in a range of 1 to 10% by weight. Have been. According to this, low-temperature baking at about 900 ° C. is possible.

[0007]

The problem to be solved by the present invention is disclosed in Japanese Patent Application Laid-Open No. 8-325.
In the porcelain composition disclosed in U.S. Pat.
-15% by weight. This PbO is generally used in such a porcelain composition because it is fired at a low temperature. However, this PbO is a harmful substance, and it is costly to treat waste and the like generated during the manufacturing process, and care must be taken in handling PbO during the manufacturing process.

[0008] Also disclosed in Japanese Patent Publication No. 6-74166.
In the porcelain composition described, B₂O ₃Is 1.5 to 5 weight
%. This B₂O₃Bake at low temperature
Therefore, it is generally used in such a porcelain composition.
You. But this B₂O₃When firing using
Since the dielectric loss at high frequencies increases, a high Q porcelain is obtained.
It is difficult to use
Boron evaporates during the process, damaging the furnace material,
Reacts with polar materials and dissolves in water and alcohol during the manufacturing process
Segregates during drying or reacts with the organic binder used.
Solving issues such as deteriorating binder performance
Need to obtain porcelain with a high Q factor
And when trying to establish a stable manufacturing process
Many problems had to be solved.

In view of the above, the present invention is a porcelain composition containing no PbO and no boron compound, having a ε of about 6 to 8, a high Q value, a small τf, Moreover, a low temperature of 1000 ° C. or less, more preferably,
An object of the present invention is to provide a dielectric ceramic composition for microwaves that can be fired at a low temperature of 900 ° C. or less, to provide a method for producing the same, and to provide an electronic component for microwaves using the same. And

[0010]

According to a first aspect of the present invention, the main component is composed of an oxide of Al, Si, Sr,
When r is converted to Al ₂ O ₃ , SiO ₂ , and SrO to obtain a total of 100% by mass, r is 10 to 6 in terms of Al ₂ O _3.
0% by mass, 25 to 60% by mass in terms of SiO ₂ , 7.5 to 50% by mass in terms of SrO, containing Al, Si, Sr,
Bi ₂ O ₃ as a sub-component with respect to the total 100% by mass
It is a dielectric ceramic composition for microwaves containing 0.1 to 10% by mass of Bi in conversion.

In the second invention, the main components are Al, Si, Sr
Al, Si, and Sr are each converted to Al
_When converted to ₂ O ₃ , SiO ₂ and SrO to give a total of 100% by mass, 10 to 60% by mass in terms of Al ₂ O ₃ and SiO 2
25 to 60% by mass in terms of _2; 7.5 to 50 in terms of SrO
Weight% of Al, Si, and containing Sr, as a sub-component relative to the total 100 mass%, 0.1 to 1 in terms _{of Bi} 2 _{O 3}
Containing 0 mass% of Bi, further 0.1 in terms of Na ₂ O
5% by mass of Na, 0.1 to 5% by mass of K in terms of K ₂ O,
At least 1% of 0.1 to 5% by mass of Co in terms of CoO
A dielectric ceramic composition for microwaves containing at least one species.

According to a third aspect of the present invention, the main components are Al, Si, Sr
Al, Si, and Sr are each converted to Al
_When converted to ₂ O ₃ , SiO ₂ and SrO to give a total of 100% by mass, 10 to 60% by mass in terms of Al ₂ O ₃ and SiO 2
25 to 60% by mass in terms of _2; 7.5 to 50 in terms of SrO
Weight% of Al, Si, and containing Sr, as a sub-component relative to the total 100 mass%, 0.1 to 1 in terms _{of Bi} 2 _{O 3}
0 mass% Bi, and 0.01 to
5 wt% of Cu, a MnO ₂ converted at 0.01 to 5 mass% of Mn, microwave dielectric ceramic composition containing at least one or more of 0.01 to 5 mass% of Ag.

According to a fourth aspect of the present invention, the main component is Al, Si, Sr
Al, Si, and Sr are each converted to Al
_When converted to ₂ O ₃ , SiO ₂ and SrO to give a total of 100% by mass, 10 to 60% by mass in terms of Al ₂ O ₃ and SiO 2
25 to 60% by mass in terms of _2; 7.5 to 50 in terms of SrO
Weight% of Al, Si, and containing Sr, as a sub-component relative to the total 100 mass%, 0.1 to 1 in terms _{of Bi} 2 _{O 3}
Containing 0 mass% of Bi, further 0.1 in terms of Na ₂ O
5% by mass of Na, 0.1 to 5% by mass of K in terms of K ₂ O,
0.1 to 5% by mass of Co in terms of CoO, containing at least one of Co, and 0.01 to 5% by mass of Cu in terms of CuO, 0.01 to 5% by mass of Mn in terms of MnO ₂ ,
It is a dielectric ceramic composition for microwaves containing at least one or more of 0.01 to 5% by mass of Ag.

According to a fifth aspect of the present invention, the main components are Al, Si, S
r, Ti, Al, Si, Sr, Ti
Are converted to Al ₂ O ₃ , SiO ₂ , SrO, and TiO ₂ to give a total of 100% by mass, respectively, 10 to 60% by mass in terms of Al ₂ O ₃ , 25 to 60% by mass in terms of SiO ₂ ,
7.5 to 50 wt% in terms of SrO, 20 in terms of TiO ₂
Containing mass% or less of Al, Si, Sr, and Ti, the total as a sub-component relative to 100 mass%, _Bi 2 _{O 3} in terms of 0.1 to 10 wt% of a microwave dielectric ceramic containing Bi A composition.

According to a sixth aspect of the present invention, the main components are Al, Si, S
r, Ti, Al, Si, Sr, Ti
Are converted to Al ₂ O ₃ , SiO ₂ , SrO, and TiO ₂ to give a total of 100% by mass, respectively, 10 to 60% by mass in terms of Al ₂ O ₃ , 25 to 60% by mass in terms of SiO ₂ ,
7.5 to 50 wt% in terms of SrO, 20 in terms of TiO ₂
Containing mass% or less of Al, Si, Sr, and Ti, as the sub ingredient with respect to the total 100 wt%, and containing Bi of 0.1 to 10 mass% in terms _{of Bi} 2 _{O 3,} further terms of Na ₂ O in microwave containing at least one or more of 0.1 to 5 mass% of Na, _{K 2} O in terms of 0.1 to 5 wt% of K, of 0.1 to 5 mass% in terms of CoO Co It is a dielectric porcelain composition.

According to a seventh aspect of the present invention, the main components are Al, Si, S
r, Ti, Al, Si, Sr, Ti
Are converted to Al ₂ O ₃ , SiO ₂ , SrO, and TiO ₂ to give a total of 100% by mass, respectively, 10 to 60% by mass in terms of Al ₂ O ₃ , 25 to 60% by mass in terms of SiO ₂ ,
7.5 to 50 wt% in terms of SrO, 20 in terms of TiO ₂
Containing mass% or less of Al, Si, Sr, and Ti, as the sub ingredient with respect to the total 100 mass%, _Bi 2 _{O 3} contained 0.1 to 10 mass% of Bi in terms 0 further terms of CuO 0.01 to 5% by mass of Cu and MnO _{2 in} terms of 0.01 to
It is a dielectric ceramic composition for microwaves containing at least one or more of 5% by mass of Mn and 0.01 to 5% by mass of Ag.

According to an eighth aspect of the present invention, the main components are Al, Si, S
r, Ti, Al, Si, Sr, Ti
Are converted to Al ₂ O ₃ , SiO ₂ , SrO, and TiO ₂ to give a total of 100% by mass, respectively, 10 to 60% by mass in terms of Al ₂ O ₃ , 25 to 60% by mass in terms of SiO ₂ ,
7.5 to 50 wt% in terms of SrO, 20 in terms of TiO ₂
Containing mass% or less of Al, Si, Sr, and Ti, as the sub ingredient with respect to the total 100 wt%, and containing Bi of 0.1 to 10 mass% in terms _{of Bi} 2 _{O 3,} further terms of Na ₂ O contains at least one more, and CuO of in 0.1 to 5 mass% of Na, _{K 2} O in terms of 0.1 to 5 wt% of K, of 0.1 to 5 mass% in terms of CoO Co 0.0 in conversion
1 to 5 mass% of Cu, Mn of 0.01 to 5 mass% with MnO ₂ in terms, is a microwave dielectric ceramic composition containing at least one or more of 0.01 to 5 mass% of Ag .

The ninth invention is directed to Al, Si, Sr or A
A microwave dielectric porcelain composition containing an oxide of l, Si, Sr, and Ti as a main component, and Bi as an auxiliary component, wherein the structure has an Al ₂ O ₃ crystal phase and at least Al, S
A dielectric ceramic composition for microwaves having a compound crystal phase containing i, Sr or Al, Si, Sr, Ti and having an fQ value of 5 THz or more.

The tenth invention is the first to ninth inventions.
The method for producing a dielectric ceramic composition for microwaves according to any one of claims 1 to ₃ , comprising a first heat treatment step for vitrifying elements other than Al ₂ O ₃ , and after the first heat treatment step, In addition to Al ₂ O ₃ , at least Al, Si, S
r or a second phase that forms a compound phase containing Al, Si, Sr, and Ti and has an fQ value of 5 THz or more.
A method for producing a dielectric ceramic composition for microwaves, comprising: In this method for producing a dielectric ceramic composition for microwaves, it is preferable that the second heat treatment step is performed at a heat treatment temperature higher than the heat treatment temperature of the first heat treatment step and 1000 ° C. or lower.

The eleventh invention is the first to ninth inventions.
An electronic component for microwaves, characterized by using any one of the dielectric ceramic compositions for microwaves according to the present invention. Electrodes may be formed on a dielectric layer made of the dielectric ceramic composition for microwaves, and a plurality of the dielectric layers may be laminated to constitute a microwave electronic component.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The dielectric ceramic composition for microwaves according to the present invention has, for example, a main component of Al, Si, Sr or Al,
It is composed of oxides of Si, Sr and Ti, each of which contains Al ₂
10 to 60% by mass in terms of O ₃ , 25 to 6 in terms of SiO ₂
0% by mass, 10 to 50% by mass in terms of SrO, 20% by mass or less in terms of TiO ₂ , and 100% by mass of the main component
On the other hand, the dielectric ceramic composition for microwaves contains 0.1 to 10% by mass of Bi in terms of Bi ₂ O ₃ as a sub-component and can be fired at a temperature of 1000 ° C. or lower or 900 ° C. or lower. Thereby, the dielectric ceramic composition of the present invention can be integrally sintered by using a metal material having high conductivity such as silver, copper, or gold as the internal electrode. Therefore, it is possible to configure a microwave electronic component having extremely low loss by using the internal electrode that uses the high Q value of the dielectric material of the present invention and suppresses the loss due to electric resistance.
Thereby, it is possible to realize a circuit device with excellent microwave characteristics and low loss by being applied to a dielectric resonator, a filter, a multilayer inductor or a multilayer capacitor, and a high-frequency multilayer substrate obtained by combining them. .

In the present invention, the dielectric ceramic composition for microwaves may further contain Na (0.1 to 5% by mass in terms of Na ₂ O) and K (0.1 to 5% in terms of K ₂ O) as accessory components. %) And Co (0.1 to 5% by mass in terms of CoO). These subcomponents have an effect of lowering the softening point of the glass when components other than Al ₂ O ₃ are vitrified in the calcining step, and a material that starts shrinking at a lower temperature is obtained.
And in the firing step, it is possible to obtain a high Q dielectric property at a firing temperature of 1000 ° C. or less,
It is preferable to include them.

In the present invention, Cu (C)
0.01 to 5 mass% in uO terms), Mn (0.01 to 5 mass% with MnO ₂ in terms), Ag: it is preferable to contain at least one or more of 0.01 to 5 mass%.
These subcomponents have an effect of promoting crystallization of the dielectric ceramic composition mainly in the firing step, and are added to achieve low-temperature sintering.

In the present invention, the reasons for specifying each component range are as follows. Al is 10 in terms of Al ₂ O ₃
If the amount is less than 10% by mass, low-temperature firing at 1000 ° C. or lower
Since the sintering density does not sufficiently increase, the porcelain becomes porous, and good characteristics cannot be obtained due to moisture absorption or the like. On the other hand, if the content is more than 60% by mass, the sintering density is not sufficiently increased even at a low temperature of 1000 ° C. or less, so that the porcelain becomes porous and good characteristics cannot be obtained due to moisture absorption or the like.

When the content of Si is less than 25% by mass in terms of SiO ₂ , the sintered density does not increase sufficiently at a low temperature of 1000 ° C. or lower, so that the porcelain becomes porous and good characteristics are obtained by moisture absorption and the like. I can't. On the other hand, if the content is more than 60% by mass, the sintering density is not sufficiently increased even at a low temperature of 1000 ° C. or less, so that the porcelain becomes porous and good characteristics cannot be obtained due to moisture absorption or the like.

When Sr is less than 10% by mass in terms of SrO, the sintering density does not increase sufficiently at a low temperature of 1000 ° C. or less, so that the porcelain becomes porous and good characteristics are obtained by moisture absorption and the like. Absent. On the other hand, if the content is more than 50% by mass, the sintering density is not sufficiently increased even at a low temperature of 1000 ° C. or lower, so that the porcelain becomes porous and good characteristics cannot be obtained due to moisture absorption or the like.

If Ti is more than 20% by mass in terms of TiO ₂ , the sintering density does not increase sufficiently at a low temperature of 1000 ° C. or less, so that the porcelain becomes porous and good characteristics are obtained by moisture absorption and the like. At the same time, the temperature coefficient of the resonance frequency of the porcelain increases with an increase in the Ti content, and good characteristics cannot be obtained. The temperature coefficient τf of the resonance frequency of the porcelain in the case where Ti is not contained increases from −20 to −40 ppm / ° C. as the blending amount of Ti increases, and
It is also easy to adjust f to 0 ppm / ° C.

Further, the dielectric porcelain composition according to the present invention comprises:
In the calcining step in the manufacturing process, SiO ₂ , S, excluding Al ₂ O ₃ , among the components constituting the dielectric ceramic composition
By vitrification of the rO and the additive of the accessory component, in the subsequent firing step, the generated glass material functions as a sintering accelerator, and densification is achieved.
It is considered that the component containing l ₂ O ₃ is crystallized to exhibit a high Q dielectric property.

Bi is added to achieve low temperature sintering. That is, by adding this Bi,
When the components other than Al ₂ O ₃ are vitrified in the calcining step, the softening point of the glass is reduced, and a material that starts shrinking at a lower temperature is obtained. It is possible to obtain high Q dielectric characteristics at the following firing temperatures. However, when the content is more than 10% by mass in terms of Bi ₂ O ₃ , the Q value becomes small. For this reason, 10 mass% or less is desirable. More preferably, it is at most 5% by mass. On the other hand, if it is less than 0.1% by mass, the effect of addition is small and crystallization at lower temperatures becomes difficult. It is more preferably at least 0.2% by mass.

When Na is less than 0.1% by mass in terms of Na ₂ O, similarly to Bi, the softening point of the glass increases and sintering at low temperatures becomes difficult. Therefore, a dense material cannot be obtained by firing at 1000 ° C. or lower. In addition, 5% by mass
If it exceeds, the dielectric loss becomes too large and practicality is lost. Therefore, the content is preferably 0.1 to 5% by mass in terms of Na ₂ O.

K is, like Na, 0.1 K in terms of K ₂ O.
If the amount is less than 1% by mass, the softening point of the glass becomes high and sintering becomes difficult, so that a dense material cannot be obtained. If the amount exceeds 5% by mass, the dielectric loss becomes too large, which is not practical. For this reason,
0.1 to 5 wt% in K ₂ O in terms are preferred.

Co, like Na, has the effect of lowering the softening point of the glass produced in the calcining step, and is added to achieve low-temperature sintering.
If the amount is less than 1% by mass, the effect of the addition is small, so that it is difficult to obtain a dense material by firing at 900 ° C. or lower. If it exceeds 5% by mass, the crystallization temperature will be 1
When the temperature becomes 000 ° C. or higher, the dielectric loss becomes too large at 1000 ° C. or lower, and practicality is lost. Therefore, the content is preferably 0.1 to 5% by mass in terms of CoO.

Ag is added in the same manner as Na to lower the softening point of the glass and to promote crystallization, and is added to achieve low-temperature sintering. %, The dielectric loss becomes too large,
Not practical. For this reason, it is preferable to add 5 mass% or less of Ag. More preferably, it is at most 2% by mass.

Further, Cu has an effect of promoting crystallization of the dielectric ceramic composition in the firing step, and is added to achieve low-temperature sintering. The effect of the addition is small, and it is difficult to obtain a material having a high Q by firing at 900 ° C. or lower. Also,
If the content exceeds 5% by mass, the low-temperature sinterability is impaired.
It is preferably 0.01 to 5% by mass in terms of O.

Mn has an effect of promoting crystallization of the dielectric ceramic composition in the firing step, similarly to Cu.
It is added to achieve low-temperature sintering, but if it is less than 0.01% by mass in terms of MnO ₂ , the effect of addition is small,
Firing at 900 ° C. or lower makes it difficult to obtain a high Q material. If the content exceeds 5% by mass, low-temperature sinterability is impaired. Therefore, the content is preferably 0.01 to 5% by mass in terms of MnO ₂ .

In the present invention, ε is about 6 to 8 and the absolute value of τf is small (50 pp) by the above specific component composition.
m / ° C or less), fQ (f is the resonance frequency) value is 5000G
It is possible to obtain a dielectric ceramic composition for microwaves that can be sintered at a temperature of not less than 1000 Hz and not less than 5 Hz (5 THz).

As described above, since firing can be performed at a temperature of 1000 ° C. or less or 900 ° C. or less, the dielectric ceramic composition of the present invention uses a metal material having high conductivity, such as silver, copper, or gold, as an internal electrode, and Sintering can be performed. Thus, by suppressing the loss due to the high Q value of the dielectric material of the present invention and the electrical resistance of the internal electrode, it is possible to configure a microwave electronic component with extremely small loss. Thereby, it is possible to realize a circuit device with excellent microwave characteristics and low loss by being applied to a dielectric resonator, a filter, a multilayer inductor or a multilayer capacitor, and a high-frequency multilayer substrate obtained by combining them. .

On the other hand, when copper is used as the internal electrode material, the firing atmosphere needs to be adjusted. When silver is used as the internal electrode material, the firing can be performed in air. Man-hours can be reduced. The dielectric ceramic composition of the present invention can be fired at 900 ° C.
Another feature is that silver can be integrally sintered in air using silver.

[0039]

The embodiments will be described below in detail. (Example 1) As starting materials, purity: 99.9%, average grain size
0.5 μm diameter Al₂O₃Powder, purity 99.9% or more,
SiO with an average particle size of 0.5 μm or less₂Powder, purity 99.9
%, SrO powder having an average particle size of 0.5 μm, purity 99.9
%, TiO2 powder having an average particle diameter of 0.5 μm, purity 99.9
%, Bi having an average particle size of 0.5 to 5 μm₂O₃Powder, Na₂
CO₃Powder, K₂CO₃Powder, CuO powder, Ag powder,
MnO2 powder, Co₃O ₄Using powder, Table 1, Table 2, Table
Weigh according to the mass ratio shown in 3.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

These powders are charged into a polyethylene ball mill, and further, zirconium oxide balls and pure water are charged, and wet mixing is performed for 20 hours. After heating and drying the mixed slurry to evaporate the water, the mixed slurry is crushed by a raikai machine, placed in an alumina crucible, and calcined at 700 to 850 ° C for 2 hours. The calcined powder is put into the above-mentioned ball mill and is charged at 20 to 40.
Wet pulverization is carried out for an hour and dried to obtain a raw material powder. 10% by mass of a 10% aqueous solution of polyvinyl alcohol is added as a binder to the powder, and the mixture is kneaded in a mortar, passed through a 32-mesh sieve, and sized to obtain a granulated powder. This powder was charged into a mold and pressed under a pressure of 2 GPa to obtain a columnar shaped sample.

This sample was heated to 600 ° C. in air for 10 minutes.
The temperature was raised at 0 ° C./h, and after 2 hours, the temperature was raised from 800 to 900 ° C. at a rate of 200 ° C./h.
Sintering was performed by cooling at a rate of 00 ° C./h, and the sintered density was calculated from the dimensions and mass of the obtained sintered body. Further, the resonance frequency f ₀ and the no-load Q value Q ₀ were obtained by the dielectric resonator method. From the dimensions of the fired body and f ₀ and Q ₀ , the f · Q value was calculated from the product of f ₀ and the reciprocal of the relative dielectric constant and the dielectric loss coefficient tan δ. The resonance frequency was 8 to 14 GHz. The results are shown in Tables 4, 5, and 6. The firing atmosphere is not limited to air, and the same dielectric characteristics are exhibited even in a non-reducing atmosphere such as nitrogen. The crystallization state of the sample is
The state of vitrification and crystallization was measured and confirmed with an X-ray diffractometer. Samples with no * mark are examples of the present invention, and sample numbers with * marks are comparative examples outside the scope of the present invention.

According to the comparative example in which the sample number is marked with *,
As described in the embodiment of the present invention, in a sample prepared outside the scope of the invention defined in the present invention, the sample is porous at a low firing temperature of 1000 ° C. or less because the sample is not densified, It is clear that the fQ value is low and the dielectric properties cannot be measured because the crystal is not crystallized even if it is densified. On the other hand, in the examples in which the sample number is not marked with *, the composition is within the range of the composition specified in the present invention.
0 ℃ or less, and even densified below sintering temperature Ioi 900 ° C., a dielectric constant of 6 to 9, fQ value or more is obtained dielectric properties 5 THz, further the temperature coefficient of the resonant frequency by the amount of TiO ₂ Is clearly controllable and can be approached to 0 ppm / ° C.

The sample No. FIG. 2 shows the X-ray diffraction pattern of the dielectric ceramic composition for microwave having the composition No. 73 after calcining at 800 ° C., and FIG. 1 shows the X-ray diffraction pattern after sintering it at 900 ° C. Show. The X-ray diffraction pattern of the 800 ° C. calcination showed a halo pattern in which elements other than the Al ₂ O ₃ crystal were vitrified, although there were some small peaks of unreacted elements and the like. In the X-ray diffraction pattern after further sintering at 900 ° C., halo patterns are reduced, and SrAl ₂ Si ₂ O ₈ and N
A crystal phase considered to be a feldspar-group solid solution containing a and K was precipitated.

[0047]

[Table 4]

[0048]

[Table 5]

[0049]

[Table 6]

Embodiment 2 Hereinafter, a laminated low-pass filter will be described with reference to FIGS. 3 and 4 as an example of an electronic component for microwave constituted by using the dielectric ceramic composition for microwave according to the present invention. FIG. 3 is a perspective view of the laminated low-pass filter, and FIG. 4 is an exploded perspective view showing the internal structure thereof.

The pulverized powder obtained in Example 1 is put into a polyethylene ball mill together with a predetermined amount of a binder (for example, polyvinyl butyral) and a plasticizer, and further a zirconium oxide ball and a solvent (for example, ethyl alcohol and butanol) are put. The slurry subjected to wet mixing for 20 hours was subjected to vacuum concentration treatment to adjust the viscosity. Next, this slurry was applied on a film by a doctor blade method and dried to obtain a green sheet. This sheet is cut into a predetermined size to form through holes 5 and 6 necessary for the component circuit, and an Ag electrode paste is applied by printing to form conductor patterns 1, 2, 3, 4 and a capacitor constituting an inductor. Constituent conductor patterns 7, 8, 9 and ground electrodes 10, 11 were formed. Further, the respective layers 12 to 17 were laminated and pressure-bonded, and cut into predetermined dimensions. After the obtained chip was subjected to degreasing firing and barrel polishing, external electrodes 20a to 20j for electrical coupling to a circuit board were formed. If the external electrode is silver-based, Ni plating is applied because solder erosion may occur and adversely affect the mechanical and electrical reliability of the electrical component. Further, solder plating is formed to improve solder wettability. In this way 2
A laminated low-pass filter 18 in which three inductors and three capacitors were connected in a π-type was obtained. When the electrical characteristics of this laminated low-pass filter were measured, excellent characteristics were obtained in which the insertion loss in the pass band was about 0.2 dB. Further, other electronic components for microwaves were formed using the dielectric ceramic composition for microwaves of the present invention, and similarly excellent electrical characteristics were obtained.

As described above, the dielectric ceramic composition of the present invention can be used at a temperature of 1000 ° C. or lower or 90 ° C. even in various production methods.
A dense sintered body can be obtained at a firing temperature of 0 ° C or less,
And the dielectric constant ε is about 6 to 9, and the absolute value of τf is 50 pp.
At m / ° C. or less, a fQ value of 5 THz or more could be obtained. Thereby, silver, copper, or gold can be used as a material for the internal electrode, and is useful for various microwave components.

[0053]

According to the present invention, a dielectric ceramic composition for microwaves is a material which can be sintered at 1000 ° C. or lower or 900 ° C. or lower, has a dielectric constant of about 6 to 9, and has a Q value of A high dielectric material can be obtained. As a result, dielectric resonators for microwaves, filters, multilayer inductors,
Excellent microwave characteristics and low loss as a microwave component such as a multilayer capacitor can be obtained. In particular, it is an excellent material for a laminated microwave component that forms an internal circuit by co-firing with an electrode material such as silver or copper, and for a high-frequency laminated substrate in which these are combined. Also, the material of the present invention, even at frequencies lower than microwaves,
Similarly, it is a material that can form a high-performance laminated circuit board,
Further, it can be used as a material that is not co-fired with the electrode material.

[Brief description of the drawings]

FIG. 1 is an X-ray diffraction pattern diagram of a microwave dielectric of the present invention after sintering.

FIG. 2 is an X-ray diffraction pattern diagram of a microwave dielectric of the present invention before sintering.

FIG. 3 is a perspective view of a microwave electronic component according to one embodiment of the present invention.

FIG. 4 is an exploded perspective view of a microwave electronic component according to one embodiment of the present invention.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H03H 7/075 H03H 7/075 A

Claims (13)

[Claims] 1. The method according to claim 1, wherein the main component is composed of oxides of Al, Si, and Sr, and Al, Si, and Sr are replaced by Al ₂ O ₃ and Si, respectively.
When converted to O ₂ and SrO to give a total of 100% by mass, A
10 to 60% by mass in terms of l ₂ O ₃ , 25 in terms of SiO ₂
６０60% by mass, 7.5 to 50% by mass of A in terms of SrO
l, Si, contains Sr, the total as a sub-component relative to 100 mass%, _Bi 2 _{O 3} microwave dielectric, characterized by containing 0.1 to 10 mass% of Bi in terms of Porcelain composition. 2. The main component is composed of oxides of Al, Si and Sr, and Al, Si and Sr are replaced by Al ₂ O ₃ and Si, respectively.
When converted to O ₂ and SrO to give a total of 100% by mass, A
10 to 60% by mass in terms of l ₂ O ₃ , 25 in terms of SiO ₂
６０60% by mass, 7.5 to 50% by mass of A in terms of SrO
l, Si, contains Sr, as a sub-component relative to the total 100 wt%, and containing Bi of 0.1 to 10 mass% in terms _{of Bi} 2 _{O 3,} further terms of Na ₂ O 0.1-5 mass% of Na, _{K 2} O in terms of 0.1 to 5 wt% of K, microwave, characterized by containing the above at least one of 0.1 to 5 mass% of Co in terms of CoO Dielectric porcelain composition. 3. The main component is composed of oxides of Al, Si, and Sr, and Al, Si, and Sr are replaced by Al ₂ O ₃ and Si, respectively.
When converted to O ₂ and SrO to give a total of 100% by mass, A
10 to 60% by mass in terms of l ₂ O ₃ , 25 in terms of SiO ₂
６０60% by mass, 7.5 to 50% by mass of A in terms of SrO
l, Si, contains Sr, as a sub-component relative to the total 100 mass%, _Bi 2 _{O 3} contained 0.1 to 10 mass% of Bi in terms of further 0.01 to 5 mass% in terms of CuO Of Cu, MnO of 0.01 to 5% by mass in terms of MnO ₂ .
A dielectric ceramic composition for microwaves, comprising at least one of Ag in an amount of from 1 to 5% by mass. 4. The main component is composed of oxides of Al, Si, and Sr, and Al, Si, and Sr are converted to Al ₂ O ₃ and Si, respectively.
When converted to O ₂ and SrO to give a total of 100% by mass, A
10 to 60% by mass in terms of l ₂ O ₃ , 25 in terms of SiO ₂
６０60% by mass, 7.5 to 50% by mass of A in terms of SrO
l, Si, contains Sr, as a sub-component relative to the total 100 wt%, and containing Bi of 0.1 to 10 mass% in terms _{of Bi} 2 _{O 3,} further terms of Na ₂ O 0.1-5 contains at least one or more of the mass% of Na, _{K 2} O in terms of 0.1 to 5 wt% of K, of 0.1 to 5 mass% in terms of CoO Co, and 0.01 in terms of CuO 5% by mass of Cu,
Mn of 0.01 to 5% by mass in terms of MnO ₂ , 0.01 to
A dielectric ceramic composition for microwaves, comprising at least one of 5% by mass of Ag. 5. The method according to claim 1, wherein the main component is composed of oxides of Al, Si, Sr, and Ti.
₂ O ₃ , SiO ₂ , SrO, TiO ₂ , and total 10
When set to 0 wt%, _Al 2 _{O 3} 10 to 60 wt% in terms of 25 to 60 wt% in terms of SiO _2, from 7.5 to 50 mass% in terms of SrO, 20 mass% of Al in terms of TiO ₂ , Si, Sr, containing Ti, relative to the total 100 wt% as an auxiliary component, calculated as _Bi 2 _{O 3} 0.1-10
What is claimed is: 1. A dielectric ceramic composition for microwaves, comprising Bi by mass. 6. Oxidation of main components Al, Si, Sr, Ti
Al, Si, Sr, and Ti are each
₂O₃, SiO₂, SrO, TiO₂Converted to 10
0% by mass, Al₂O₃10-60 mass in conversion
%, SiO₂25-60 mass% in conversion, SrO conversion
7.5 to 50% by mass, TiO₂20% by mass or less in conversion
Al, Si, Sr, Ti, 100 mass in total
% As an accessory component to Bi₂O₃0.1 to 10 in conversion
% Bi by mass and Na ₂0.1-5 in O conversion
Mass% Na, K₂0.1 to 5% by mass of K and C in terms of O
at least one of 0.1 to 5% by mass of Co in terms of oO;
Microwave induction characterized by containing at least one species
Electric porcelain composition. 7. The main component is composed of oxides of Al, Si, Sr and Ti, and Al, Si, Sr and Ti are
₂ O ₃ , SiO ₂ , SrO, TiO ₂ , and total 10
When set to 0 wt%, _Al 2 _{O 3} 10 to 60 wt% in terms of 25 to 60 wt% in terms of SiO _2, from 7.5 to 50 mass% in terms of SrO, 20 mass% of Al in terms of TiO ₂ , Si, Sr, containing Ti, relative to the total 100 wt% as an auxiliary component, calculated as _Bi 2 _{O 3} 0.1-10
% Of Bi, and 0.01 to 5 in terms of CuO.
% Of Cu, 0.01 to 5% by weight of M in terms of MnO ₂
n. A dielectric ceramic composition for microwaves, comprising at least one or more of Ag of 0.01 to 5% by mass. 8. Oxidation of Al, Si, Sr, and Ti as main components
Al, Si, Sr, and Ti are each
₂O₃, SiO₂, SrO, TiO₂Converted to 10
0% by mass, Al₂O₃10-60 mass in conversion
%, SiO₂25-60 mass% in conversion, SrO conversion
7.5 to 50% by mass, TiO₂20% by mass or less in conversion
Al, Si, Sr, Ti, 100 mass in total
% As an accessory component to Bi₂O₃0.1 to 10 in conversion
% Bi by mass and Na ₂0.1-5 in O conversion
Mass% Na, K₂0.1 to 5% by mass of K and C in terms of O
at least one of 0.1 to 5% by mass of Co in terms of oO;
At least 0.01% by mass in terms of CuO
Cu, MnO₂Mn of 0.01 to 5% by mass in conversion,
At least one or more of 0.01 to 5% by mass of Ag
Microwave dielectric porcelain characterized by containing
Composition. 9. Al, Si, Sr or Al, Si, S
A dielectric ceramic composition for microwaves comprising an oxide of r and Ti as a main component and Bi as an auxiliary component, wherein the structure has an Al ₂ O ₃ crystal phase and at least Al, Si, Sr or Al, Si. , Sr, Ti
A dielectric ceramic composition for microwaves having a Q value of 5 THz or more. 10. The method for producing a dielectric ceramic composition for microwave according to any one of claims 1 to 9, wherein
_A first heat treatment step for vitrifying elements other than ₂ O ₃ ,
After the first heat treatment step, Al ₂ O ₃ is added to the structure.
In addition to at least Al, Si, Sr or Al, Si, S
forming a compound crystal phase containing r and Ti, and f
A method for producing a dielectric ceramic composition for microwaves, comprising a second heat treatment step so that the Q value becomes 5 THz or more. 11. The microwave dielectric ceramic composition according to claim 10, wherein the second heat treatment step is performed at a heat treatment temperature higher than the heat treatment temperature of the first heat treatment step and 1000 ° C. or less. Production method. 12. An electronic component for microwaves, comprising using the dielectric ceramic composition for microwaves according to any one of claims 1 to 9. 13. The microwave electron according to claim 12, wherein an electrode is formed on a dielectric layer made of the dielectric ceramic composition for microwave, and a plurality of the dielectric layers are laminated. parts.