JP2002265266A - Dielectric porcelain composition and dielectric device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dielectric porcelain composition which has a high Qu value, εr (dielectric constant) of about 10 to 30 and a small absolute value of τf, and is burnable at <=950 deg.C. SOLUTION: A dielectric porcelain composition containing a first component and a second component (25 to 80 wt.%) is used. The first component is multiple oxide expressed by the compositional formula of xZrO2 -yTiO2 -zL(1+u)/3 M(2-u)/3 O2 (L is at least one kind of element selected from the groups consisting of Mg, Zn, Co and Mn; M is at least one element selected from the groups consisting of Nb and Ta; and, (x), (y), (z) and (u) are numerical values expressed by x+y+z=1, 0.10<=x<=0.60, 0.20<=y<=0.60, 0.01<=z<=0.70, and 0<=u<=1.90). The second component is a glass composition containing the oxide of at least one kind of element selected from the groups consisting of Si, B, Al, Ba, Ca, Sr, Zn, Ti, La and Nd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dielectric porcelain composition and a dielectric device. The dielectric ceramic composition of the present invention is particularly suitable as a material for a dielectric device used in a high frequency region such as a microwave or a millimeter wave band.

[0002]

2. Description of the Related Art In recent years, dielectric ceramics have been widely used for dielectric resonators and dielectric filters used in microwave and millimeter wave regions. For a dielectric used in such an application, the unloaded Q value (Qu value) is high, the relative permittivity (εr) is large, and the temperature coefficient (τf) of the resonance frequency is small and arbitrary. It has been required to be able to change to However, the larger the dielectric constant of the dielectric porcelain, the smaller the dielectric device. For this reason, a dielectric ceramic composition having a relatively small relative dielectric constant has been demanded in consideration of processing accuracy and conductor loss of a dielectric device with an increase in the frequency of a communication system.

On the other hand, by simultaneously firing a dielectric ceramic composition and a conductor having high conductivity (eg, Ag), a low-loss and inexpensive dielectric device can be realized. For this purpose, a dielectric porcelain composition that can be fired at a temperature of 950 ° C. or lower is required.

[0004] As the dielectric constant is small dielectric ceramic composition, conventionally, MgTiO ₃ -CaTiO ₃ based ceramic (see JP-A-6-92727) and, Al ₂ O ₃ based ceramic, and, Al ₂ O ₃ A porcelain composition in which a glass composition is added to a system porcelain is known.

[0005]

However, MgT
iO ₃ -CaTiO ₃ based ceramic is the dielectric properties are relatively good, can not be fired at 950 ° C. or lower. Also,
Al ₂ O ₃ -based porcelain has a high Qu value and a small εr of about 10, but has a large τf and cannot be fired at a temperature of 950 ° C. or lower. A porcelain composition obtained by adding a glass composition to an Al ₂ O ₃ porcelain has too large τf.

Accordingly, the present invention provides a high unloaded Q (Qu) value, a relative dielectric constant (εr) of about 10 to 30, a small absolute value of the temperature coefficient (τf) of the resonance frequency, and
An object of the present invention is to provide a dielectric ceramic composition that can be fired at a temperature of 950 ° C. or lower. Another object of the present invention is to
An object of the present invention is to provide a low-loss and low-cost dielectric device suitable for use in a high-frequency region such as a microwave band or a millimeter wave band.

[0007]

To achieve the above object, a dielectric ceramic composition of the present invention comprises a first component and a second component, and the content of the second component is from 25% by weight to 80%. weight%
Is within the range. The first component has a composition formula of xZrO ₂ −
It is a composite oxide represented by yTiO ₂ -zL _{(1 + u) / 3} M _{(2-u) / 3} O ₂ . The second component is Si, B, Al, B
It is a glass composition containing an oxide of at least one element selected from the group consisting of a, Ca, Sr, Zn, Ti, La and Nd. Here, L is at least one element selected from the group consisting of Mg, Zn, Co and Mn, M is at least one element selected from the group consisting of Nb and Ta, and x, y, z and u are It is a numerical value within the range represented by the following formula. x + y + z = 1 0.10 ≦ x ≦ 0.60 0.20 ≦ y ≦ 0.60 0.01 ≦ z ≦ 0.70 0 ≦ u ≦ 1.90

According to the above dielectric ceramic composition, the Qu value can be increased, the εr can be set to about 10 to 30, and the absolute value of τf can be reduced. Further, the dielectric ceramic composition,
It can be fired at a temperature of 950 ° C. or less. Note that u is 0 <u
It is preferable to satisfy the following. Further, the second component is preferably a glass composition containing Si and B (boron).

In the dielectric ceramic composition of the present invention, a preferable example of the second component is 30 to 60% by weight of SiO ₂ ,
A glass composition comprising ３０30% by weight of B ₂ O ₃ , 2-10% by weight of Al ₂ O ₃ and 20-50% by weight of QO.
Another preferred example of the second component is 30-60% by weight of Si
O ₂ , 2 to 10 wt% B ₂ O ₃ , 2 to 10 wt% Al ₂
O _3, a glass composition comprising La ₂ O ₃ 20 to 50 wt% of QO and 5-15% by weight. Another preferred example of the second component is 40 to 60% by weight of SiO2, ₂ to 1%.
0 wt% of B ₂ O _3, 2~10 wt% of Al ₂ O _3, 20~
A glass composition comprising 50% by weight of QO and 1 to 5% by weight of ZnO. Yet another preferred embodiment of the second component is 15 to 30 wt% of SiO _2, 5 to 20 wt% of B
aO, 5-15 wt% RO, 10-25 wt% Zn
O, it is a glass composition comprising 10 to 30 wt% of TiO ₂ and 10 to 30 wt% of T ₂ O _3. In the above description of the second component, Q is at least one element selected from the group consisting of Ba and Ca, and R is Ca and Sr
At least one element selected from the group consisting of
T is at least one element selected from the group consisting of La and Nd.

[0010] In the dielectric ceramic composition of the present invention, the first component is at least one element selected from the group consisting of Mg, Zn, Co and Mn, and at least one element selected from the group consisting of Nb and Ta. It is preferable that the ZrTiO ₄ phase in which the solid solution substitution is performed is used as the main phase. In addition,
In the present specification, the “main phase” means that the content is 50% by weight.
The above components are referred to. In the first component, 0.5 ≦
It is preferable that a / b ≦ 1.9. Where a is
Mg are dissolved replaced ZrTiO _4, Zn, the sum of the molar fraction of at least one element selected from the group consisting of Co and Mn, b is, Nb in solid solution substitution in ZrTiO ₄ and Ta Is the sum of the mole fractions of at least one element selected from the group consisting of

[0011] A dielectric device of the present invention includes a dielectric porcelain and a conductor formed so as to be in contact with the dielectric porcelain, wherein the dielectric porcelain comprises the dielectric porcelain composition of the present invention, and the conductor is It is characterized by containing at least one element selected from Ag and Pd as a main component. This dielectric device is suitable for use in a high frequency region such as a microwave band or a millimeter wave band, and has low loss. In addition, this dielectric device can be manufactured at low cost because the dielectric porcelain and the conductor can be fired simultaneously.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below.

(Embodiment 1) In Embodiment 1, a dielectric ceramic composition of the present invention will be described. The dielectric ceramic composition of the present invention contains a first component and a second component, and the content of the second component is in the range of 25% by weight to 80% by weight. The dielectric ceramic composition of the present invention may be composed of only the first component and the second component. If the content of the second component is out of the above range, it cannot be fired at a temperature of 950 ° C. or lower, or a high Qu value cannot be obtained. The content of the second component is 35
More preferably, it is in the range of from 75% by weight to 75% by weight.

The second component is composed of Si, B, Al, Ba,
It is a glass composition containing an oxide of at least one element selected from the group consisting of Ca, Sr, Zn, Ti, La and Nd. As specific examples of the second component, four preferable examples are shown below. (1) 30 to 60 wt% of SiO _2, 2 to 30 wt% of B ₂ O _3, 2~10 wt% of Al ₂ O ₃ and 20 to 50% by weight glass composition comprising QO of. (2) 30-60 wt% of SiO _2, 2 to 10 wt% of B ₂ O _3, 2 to 10 wt% of Al ₂ O _3, 20 to 50 wt%
Glass composition comprising La ₂ O ₃ of QO and 5-15 wt%. (3) 40-60% by weight of SiO ₂ , 2-10% by weight of B ₂ O ₃ , 2-10% by weight of Al ₂ O ₃ , 20-50% by weight
A glass composition comprising QO and 1-5 wt% ZnO. (4) 15 to 30 wt% of SiO _2, 5 to 20 wt% of BaO, 5 to 15 wt% of RO, 10 to 25 wt% of Z
nO, 10-30 wt% of the glass composition comprising TiO ₂ and 10 to 30 wt% of T ₂ O _3.

Here, similarly to the above, Q is Ba and C
a is at least one element selected from the group consisting of Ca, S is at least one element selected from the group consisting of Ca and Sr, and T is at least one element selected from the group consisting of La and Nd. is there. When the second component is out of the above range, the second component may not be vitrified or may have an excessively high hygroscopicity.

The first component has a composition formula xZrO ₂ -yT
iO is a _{2 -zL (1 + u) /} 3 M composite oxide represented by _{(2-u) / 3 O} 2. Here, L is at least one element selected from the group consisting of Mg, Zn, Co and Mn.
Represents at least one selected from the group consisting of Nb and Ta
Elements. Further, x, y, z and u are represented by “x +
y + z = 1 ”,“ 0.10 ≦ x ≦ 0.60 ”,“ 0.2
0 ≦ y ≦ 0.60 ”,“ 0.01 ≦ z ≦ 0.70 ”,
It is a numerical value that satisfies “0 ≦ u ≦ 1.90”. x, y and z are, respectively, ZrO ₂ , TiO ₂ and L _{(1 + u) / 3}
M is equal to _{(2-u) / 3 O} 2 mole fraction. x, y, z and u
Is outside the above range, a high Qu value cannot be obtained. x,
y, z and u are 0.300 ≦ x ≦ 0.400;
0.400 ≦ y ≦ 0.560 and 0.100 ≦ z ≦ 0.
It is particularly preferable to satisfy 300 and 0.01 ≦ u ≦ 0.20.

It is preferable that the first component has a ZrTiO ₄ phase in which the above-mentioned element L and the above-mentioned element M are solid-solution substituted as a main phase. In other words, the first component is preferably composed mainly of ZrTiO _{4 in} which the above-mentioned element L and the above-mentioned element M are solid-solution substituted. In the present specification, the “main component”
A component having a content of 50% by weight or more. ZrTiO ₄ in which element L and element M are dissolved (that is, ZrTiO ₄
, And a solid solution of element L and element M) have a slightly different crystal structure from ZrTiO ₄ crystal. The first component is ZrTiO
_In the case where the solid solution of ( ₄ ) is the main component, the mole fraction a of the solid solution element L and the mole fraction b of the solid solution element M are 0.5 ≦ a / b ≦ 1. .9 (more preferably 0.5
08 ≦ a / b ≦ 0.667).

An example of the method for producing the dielectric ceramic composition of the present invention will be described below. First, a powder of a starting material for a dielectric porcelain is prepared, and this powder is mixed. The starting material of the dielectric porcelain is not particularly limited, and oxides, carbonates, hydroxides, chlorides, alkoxides, or the like of each component element can be used.

As a method for mixing the raw material powders, a wet mixing method in which the powders are mixed together with water or an organic solvent in a ball mill can be used. Also, a dry mixing method of mixing with a mixer or the like or mixing in a ball mill without using a solvent can be used. Further, an alkoxide method or a coprecipitation method can be used depending on the starting materials. Among these mixing methods, a method of mixing in a ball mill using a solvent is preferable because the process is relatively simple and a homogeneous mixture is easily obtained. Note that a dispersant may be used or pH may be adjusted to enhance the dispersibility of the powder.

Next, the obtained mixture is calcined. The conditions for calcining the mixture vary depending on the composition, but are usually 700.
Heating may be performed at a temperature of about 1300 ° C. for about 1 to 8 hours. When vitrification is necessary, the mixture that has been heated and melted may be rapidly cooled. The quenching can be performed by dropping the molten mixture into water or dropping it on a metal plate.

Next, the obtained calcined product or glass compound is pulverized into a powder. Grinding of calcined product or glass compound is performed by ball mill, high-speed rotary grinder, medium stirring mill,
Alternatively, it can be performed using an airflow pulverizer or the like.

Next, a binder is added to the obtained powder, followed by molding. The molding of the powder is usually performed by press molding. Although not particularly limited, the pressure in press molding is preferably about 50 to 200 MPa. The binder is not particularly limited as long as it is a binder used at the time of molding the ceramic. For example, polyvinyl alcohol-based binder, polyvinyl butyral-based binder,
An acrylic resin-based binder, a wax-based binder, or the like can be used. Although the amount of the binder used is not particularly limited, it is usually preferable to set the content of the binder (solid content) to about 0.05 to 1% by weight of the whole.

Next, the formed material is fired to obtain a dielectric ceramic made of the composition of the present invention. The firing conditions are not particularly limited, but after heating at about 400 to 700 ° C. for about 1 to 24 hours to remove the binder,
It is preferable to bake at about 800 to 950 ° C. for about 2 to 100 hours.

Embodiment 2 In Embodiment 2, a dielectric device of the present invention will be described. The dielectric device of the present invention includes a dielectric porcelain made of the dielectric porcelain composition of Embodiment 1 and a conductor (for example, two pieces) formed inside and / or on the surface of the dielectric porcelain so as to be in contact with the dielectric porcelain. Above electrode patterns). This conductor can be formed of a metal containing at least one element selected from Ag and Pd as a main component, and can be formed of, for example, Ag alone or Pd alone.

Examples of the dielectric device of the present invention include a dielectric filter, a dielectric resonator, a dielectric duplexer, and a dielectric coupler. An example of the dielectric filter among them will be described in a second embodiment.

[0026]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

Example 1 In Example 1, an example of the dielectric ceramic composition of the present invention will be described.

As starting materials for the first component, ZrO ₂ , T
iO ₂ , MgO, ZnO, CoO, Nb ₂ O ₅ , Ta
₂ O ₅ and Mn ₃ O ₄ were prepared. Then, these were weighed to have a predetermined composition, and wet-mixed with ethanol using a ball mill. The volume ratio between the powder and ethanol was about 2: 3. The mixture was taken out of the ball mill and dried at 120 ° C.
The mixture was calcined at a temperature of 2 ° C. for 2 hours to obtain a dielectric crystal (first component) powder.

As starting materials for the second component, SiO ₂ , B ₂
O ₃ , Al ₂ O ₃ , BaO, CaO, SrO, ZnO, T
iO ₂ , La ₂ O ₃ , and Nd ₂ O ₃ were prepared. Then, these were weighed to have a predetermined composition, and wet-mixed with ethanol using a ball mill. The volume ratio between the powder and ethanol was about 2: 3. The mixture was removed from the ball mill and dried at 120 ° C. Further, the dried mixture was placed in a platinum crucible, and exposed to air for 130 minutes.
Melted at a temperature of 0 ° C. Then, the melt was quenched by dropping it into water to obtain glass. The obtained glass was pulverized and dried in the same manner as in the mixing to obtain a glass powder (second component).

Next, the dielectric powder (first component) and the glass powder (second component) were blended at a predetermined ratio, and wet pulverized together with ethanol in a ball mill to obtain a slurry. The slurry was taken out of the ball mill and dried to obtain a powder. 8% by weight of a polyvinyl alcohol solution having a concentration of 6% as a binder was added to this powder, mixed and homogenized, and the obtained mixture was sized through a 32 mesh sieve. The sized powder was molded into a disk (diameter 13 mm, thickness about 6 mm) at a molding pressure of 130 MPa using a mold and a hydraulic press. This compact was placed in a high-purity magnesia pod and kept in air at a temperature of 500 ° C. for 4 hours to remove the binder. afterwards,
The sintering was carried out in air at a temperature of 800 to 950 ° C. for 4 hours. Thus, a dielectric ceramic made of the dielectric ceramic composition of the present invention was obtained.

The electrical characteristics of the obtained dielectric porcelain were evaluated. Specifically, the Hakki-Coleman resonator method using a network analyzer (Hakki
and Coleman's resonator m
method: In another expression, the Qf value (the product of the Qu value and the resonance frequency) and the relative permittivity (εr) were obtained from the measurement by the conductor cavity type dielectric cylinder resonator method). The temperature coefficient (τf) of the resonance frequency was determined in the range of −25 ° C. to 85 ° C. The resonance frequency was in the range of 6 to 13 GHz.

Table 1 shows the composition and state of the produced second component, and Table 2 shows the composition of the obtained dielectric ceramic composition. Table 3 shows the electrical characteristics. Samples marked with * in Tables 2 and 3 are comparative examples.

(Table 1) 記号 symbol Glass composition Glass (% by weight) ) State SiO ₂ B ₂ O ₃ Al ₂ O ₃ BaO CaO ZnO La ₂ O ₃ SrO TiO ₂ Nd ₂ O ₃ ─────────────────────── ───────────── e 78 1 1 5 5 8 2 Not vitrified f 10 40 15 35 Hygroscopic Yes g 15 15 60 10 Not vitrified h 30 30 10 15 15 Good i 60 2 2 36 good j 40 5 5 25 25 good k 50 20 10 20 good l 60 10 2 20 8 good m 30 10 5 25 25 5 good n 43 2 10 30 15 good p 44 5 6 35 10 good q 60 10 2 13 10 5 good r 40 2 7 35 15 1 good s 55 10 10 20 5 good t 50 5 5 25 13 2 good v 15 20 10 10 15 5 10 15 good w 30 5 3 25 5 2 25 5 good A 20 15 7 10 5 3 30 10 Good B 18 17 5 15 5 22 18 Good C 22 13 3 15 7 18 22 Good D 19 16 8 13 4 20 20 Good ─────────────── ─────────── ──────────

(Table 2) 試 料 Sample First component Second component No. LMxyzu Sample content (% by weight) ──────────────────────────────────── * 1 Mg Nb 0.400 0.150 0.450 0 p 40 2 Mg Nb 0.200 0.200 0.600 0 p 40 3 Mg Nb 0.450 0.200 0.350 0 p 40 4 Mg Nb 0.200 0.600 0.200 0 p 40 5 Zn Nb 0.200 0.600 0.200 0 p 40 * 6 Mg Nb 0.150 0.700 0.150 0 p 40 7 Mg Nb 0.100 0.200 0.700 0 p 40 * 8 0.550 0.450 0 0 p 40 9 Mg Nb 0.490 0.500 0.010 0 p 40 10 Zn Nb 0.490 0.500 0.010 0 p 40 11 Mg Nb 0.350 0.450 0.200 0 p 40 12 Mg _9/10 Nb 0.340 0.520 0.140 0 p 40 Mn _1/10 13 Zn _9/10 Nb 0.340 0.520 0.140 0 p 40 Mn _1/10 14 Mn Nb 0.340 0.520 0.140 0 p 40 15 Mg _9/10 Ta 0.340 0.520 0.140 0 p 40 Mn _1/10 16 Mg _9/10 Nb _1/2 0.340 0.520 0.140 0 p 40 Mn _1/10 Ta _1/2 17 Mg _9/10 Nb 0.340 0.520 0.140 0.1 p 40 Mn _1/10 18 Mg _{9 / 10} Nb 0.3 40 0.520 0.140 0.96 p 40 Mn _1/10 19 Mg _9/10 Nb 0.340 0.520 0.140 1.9 p 40 Mn _1/10 * 20 Mg _9/10 Nb 0.340 0.520 0.140 1.95 p 40 Mn _1/10 * 21 Mg Nb 0.650 0.200 0.150 0 p 40 22 Mg Nb 0.600 0.300 0.100 0 p 40 * 23 Mg Nb 0.050 0.500 0.450 0 p 40 * 24 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 15 Mn _1/10 25 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 25 Mn _1/10 26 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 35 Mn _1/10 27 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 43 Mn _1/10 28 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 60 Mn _1/10 29 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 70 Mn _1/10 * 30 Mg _9/10 Nb 0.360 0.540 0.100 0.1 p 90 Mn _1/10 31 Mg _9/10 Nb 0.360 0.540 0.100 0.1 h 43 Mn _{1 / 10} 32 Mg _9/10 Nb 0.360 0.540 0.100 0.1 i 43 Mn _1/10 33 Mg _9/10 Nb 0.360 0.540 0.100 0.1 j 43 Mn _1/10 34 Mg _9/10 Nb 0.360 0.540 0.100 0.1 k 35 Mn _1/10 35 Mg _9/10 Nb 0.360 0.540 0.100 0.1 k 43 Mn _1/10 36 Mg _9/10 Nb 0.360 0.540 0.100 0.1 k 60 Mn _1/10 37 Mg _9/10 Nb 0.360 0.540 0.100 0.1 l 43 Mn _1/10 38 Mg _9/10 Nb 0.360 0.540 0.100 0.1 m 43 Mn _1/10 39 Mg _9/10 Nb 0.360 0.540 0.100 0.1 n 43 Mn _1/10 40 Mg _9/10 Nb 0.360 0.540 0.100 0.1 q 43 Mn _1/10 41 Mg _9/10 Nb 0.360 0.540 0.100 0.1 r 43 Mn _1/10 42 Mg _9/10 Nb 0.360 0.540 0.100 0.1 s 43 Mn _1/10 43 Mg _9/10 Nb 0.360 0.540 0.100 0.1 t 35 Mn _1/10 44 Mg _9/10 Nb 0.360 0.540 0.100 0.1 t 43 Mn _1/10 45 Mg _9/10 Nb 0.360 0.540 0.100 0.1 t 60 Mn _1/10 46 Co _9/10 Nb _1/2 0.340 0.520 0.140 0 p 40 Mn _1/10 Ta _1/2 47 Co _9/10 Nb 0.340 0.520 0.140 0.1 p 40 Mn _1/10 48 Co _9/10 Nb 0.340 0.520 0.140 0.96 p 40 Mn _1/10 49 Mg _9/10 Nb 0.340 0.520 0.140 0.1 v 70 Mn _1/10 50 Mg _9/10 Nb 0.340 0.520 0.140 0.1 w 70 Mn _1/10 51 Mg _9/10 Nb 0.340 0.520 0.140 0.1 A 70 Mn _1/10 52 Mg _9/10 Nb 0.340 0.520 0.140 0.1 B 70 Mn _1/10 53 Mg _9/10 Nb 0.340 0.520 0.140 0.1 C 75 Mn _1/10 54 Mg _9/10 Nb 0.340 0.520 0.140 0.1 D 75 Mn _1/10 55 Mg _9/10 Nb 0.340 0.520 0.140 0.1 D 80 Mn _1/10 ───────────────────────────── ─────── In Table 2, x, y, z and u represent the first component _{Narushiki: xZrO 2 -yTiO 2 -zL (1} + u) / 3 M (2-u) / 3 O
₂ (L and M are as described above). When a plurality of elements are indicated as elements L and M, such as Mg _9/10 and Mn _1/10 , _9/10 and 1/10
The molar fraction of each element is shown.

(Table 3) 試 料 Sample firing temperature Qf εr τf number (° C) (GHz) (ppm) / ℃) ──────────────────────────── * 1 950 Unmeasurable 2 950 4000 12.3 -40 3 950 4500 16.2 12 4 900 4200 19.8 38 5 850 4300 18.5 29 * 6 900 950 32.2 67 7 950 4900 10.8 -38 * 8 950 800 18.8 78 9 900 4000 18.5 37 10 900 4200 16.9 23 11 900 6000 17.2 16 12 900 9500 18.0 5 13 850 8600 16.9- 3 14 850 6200 15.2 25 15 900 9900 16.7 1 16 900 11000 17.8 2 17 900 13600 17.5 -2 18 900 10900 15.3 -12 19 950 6800 14.1 -25 * 20 950 650 11.3 -56 * 21 950 Measurement impossible 22 950 4200 14.6 36 * 23 950 360 15.9 54 * 24 950 Unmeasurable 25 950 6000 12.3 29 26 950 12000 16.4 12 27 900 14200 17.8 2 28 850 12300 15.0 -8 29 800 8500 12.4 18 * 30 800 670 9.8 32 31 950 6800 16.5 25 32 950 6000 15.8 13 33 950 6300 16.1 10 34 950 8100 15.8 21 35 900 10600 18.4 7 36 850 7400 13.4 -9 37 900 9500 16.9 16 38 900 8400 16.3 7 39 900 7500 16.5 12 40 950 6300 15.2 29 41 950 7400 16.0 16 42 950 8500 16.3 9 43 950 9500 15.9 22 44 900 11200 17.5 6 45 850 10000 15.9 -8 46 900 9600 17.5 8 47 900 12400 17.8 2 48 900 10000 16.0 -3 49 900 4000 29.8 18 50 900 4200 19.6 -16 51 900 4500 24.9 -8 52 900 4800 26.4 -5 53 850 4700 27.0 -11 54 850 4100 26.5 -9 55 850 4050 25.8 -7 示 す As shown in Table 3, high Qf of 4000 or more Value (4000 or more), ε of about 10 to 30
r, τf having a small absolute value (40 ppm / ° C. or less in absolute value) could be obtained. In addition, the high electrical characteristics could be achieved at a low firing temperature of 950 ° C. or less. On the other hand, in the sample of the comparative example marked with *, the electrical characteristics could not be measured without sintering, or even if sintering was possible, at least one of the above-mentioned characteristics (Qf value, εr, τf) was within the above-mentioned preferred range. Did not enter. In the sample of the comparative example, particularly, the Qf value was significantly reduced.

For samples other than the comparative example, powder X-ray diffraction
The measurement showed that ZrTiO_FourThe phases were confirmed. Ma
ZrTiO_FourFracture surface of dielectric porcelain whose main phase is
And the polished surface, the composition using a local X-ray diffractometer
The analysis showed that Zr, Ti, element L
And all of the element M were confirmed to be present. Further
In addition, the composition ratio depends on the crystal grains constituting the main phase.
Qualitatively identical. All ingredients formulated as the first component
Confirmation that element L and element M exist in a single crystal grain
Was done. In addition, Zr, Ti,
In the dielectric porcelain where each element of element L and element M exists
Is the ZrTiO obtained under the same firing conditions. _FourCompare with porcelain
As a result, it was confirmed that the lattice constant was increased. This
From these, ZrTiO_FourThe phases include the element L and the element
It was confirmed that both of the element M were subjected to solid solution substitution.

With respect to the above dielectric porcelain, the mole fractions of the elements L and M dissolved in the ZrTiO ₄ phase were quantified using a local X-ray diffractometer. As a result, the dielectric porcelain having the value of a / b of 0.5 or more and 1.9 or less (sample number 1)
1 to 18, 25 to 29, 31 to 48), it was confirmed that a higher Qf value (6000 or more) was exhibited.

(Example 2) In Example 2, an example in which a dielectric filter was manufactured using the same dielectric ceramic composition as Sample Nos. 16, 27 and 44 of Example 1 will be described.

In Example 2, a laminated dielectric filter 10 as shown in FIG. 1 was manufactured. Dielectric filter 10
Includes a dielectric porcelain 1 and electrodes formed inside and on the surface of the dielectric porcelain 1. A method for manufacturing the dielectric filter 10 will be described with reference to FIG. First, unsintered sheets 3a, 3b, 3 made of a dielectric ceramic composition
c, 3d and 3e are formed, and the internal electrodes 4a, 4b, 4c, 4d, 4e, 4f and 4
g formed. The same dielectric porcelain composition as that of Sample No. 16, 27 or 44 of Example 1 was used as the dielectric porcelain composition. The internal electrodes were formed of Ag paste.

Next, the sheets 3a to 3e were laminated, and an Ag paste was applied to the laminate to form terminal electrodes 2a, 2b, 2c and 2d. Finally, the laminate and the electrodes were fired simultaneously. The firing was performed under the same conditions as in Example 1.

When the performance of this dielectric filter was evaluated, the insertion loss was one half that of a conventional dielectric filter using a composition obtained by adding glass to Al ₂ O ₃ . Further, the temperature coefficient at the center frequency (about 5 GHz) is about 10 times smaller than that of the conventional dielectric filter.
It was one in one. From the above, it was confirmed that the dielectric device of Example 2 can be used as a low-loss dielectric device suitable for use in a high frequency region such as a microwave band or a millimeter wave band. As described above, the laminated dielectric device of the present invention can be manufactured by simultaneously firing the dielectric ceramic composition and an electrode material such as an Ag paste, so that it can be manufactured extremely efficiently.

Although the embodiments of the present invention have been described with reference to the examples, the present invention is not limited to the above embodiments, but can be applied to other embodiments based on the technical idea of the present invention. .

[0043]

As described above, according to the present invention,
A dielectric ceramic composition having a high Qu value, a εr of about 10 to 30, a small absolute value of τf, and being sinterable at a temperature of 950 ° C. or less can be obtained. According to the present invention,
A low-loss and inexpensive dielectric device suitable for use in a high frequency region such as a microwave band or a millimeter wave band can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a dielectric device of the present invention.

FIG. 2 is a perspective view showing an internal electrode structure of an example of the dielectric device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dielectric porcelain 2a, 2b, 2c, 2d Terminal electrode 3a, 3b, 3c, 3d, 3e Sheet 4a, 4b, 4c, 4d, 4e, 4f, 4g Internal electrode 10 Dielectric filter

Continued on the front page (72) Inventor Junichi Kato 1006 Kadoma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. 4G031 AA03 AA04 AA05 AA06 AA07 AA09 AA11 AA12 AA14 AA15 AA19 AA22 AA26 AA28 AA29 AA30 BA09 5G303 AA07 AB06 AB08 AB10 AB15 CA01 CA03 CB09 CB17 CB18 CB21 CB33 CB35 00638 CB38

Claims (8)

[Claims] 1. A dielectric porcelain composition comprising a first component and a second component, wherein the content of the second component is in a range of 25% by weight to 80% by weight, and the first component is Having the composition formula xZrO ₂ -yTiO ₂ -zL
A composite oxide represented by _{(1 + u) / 3} M _{(2-u) / 3} O ₂ , wherein the second component is Si, B, Al, Ba, Ca, Sr,
A dielectric ceramic composition comprising a glass composition containing an oxide of at least one element selected from the group consisting of Zn, Ti, La and Nd. Where L is M
g is at least one element selected from the group consisting of Zn, Co and Mn; M is at least one element selected from the group consisting of Nb and Ta;
z and u are numerical values within the range represented by the following formula. x + y + z = 1 0.10 ≦ x ≦ 0.60 0.20 ≦ y ≦ 0.60 0.01 ≦ z ≦ 0.70 0 ≦ u ≦ 1.90 2. The method according to claim 1, wherein the second component comprises 30 to 60% by weight of S.
iO ₂ , 2-30% by weight B ₂ O ₃ , 2-10% by weight A
The dielectric ceramic composition according to claim 1, which is a glass composition comprising QO of l ₂ O ₃ and 20 to 50 wt%. However,
Q is at least one element selected from the group consisting of Ba and Ca. 3. The method according to claim 2, wherein the second component is 30 to 60% by weight of S.
iO ₂ , 2-10% by weight B ₂ O ₃ , 2-10% by weight A
l ₂ O _3, 20~50 wt% of QO and 5-15 wt%
The dielectric porcelain composition according to claim 1, which is a glass composition containing the following La ₂ O ₃ . Here, Q is at least one element selected from the group consisting of Ba and Ca. 4. The method according to claim 1, wherein the second component comprises 40 to 60% by weight of S.
iO ₂ , 2-10% by weight B ₂ O ₃ , 2-10% by weight A
l ₂ O _3, a dielectric ceramic composition according to claim 1, which is a glass composition comprising 20 to 50 wt% of QO and 1-5 wt% of ZnO. Here, Q is at least one element selected from the group consisting of Ba and Ca. 5. The method according to claim 1, wherein the second component is 15 to 30% by weight of S.
iO ₂ , 5-20 wt% BaO, 5-15 wt% R
O, 10-25 wt% ZnO, 10-30 wt% T
The dielectric ceramic composition according to claim 1, which is a glass composition comprising iO ₂ and 10 to 30 wt% of T ₂ O _3. Here, R is at least one element selected from the group consisting of Ca and Sr, and T is at least one element selected from the group consisting of La and Nd. 6. The first component, wherein at least one element selected from the group consisting of Mg, Zn, Co and Mn and at least one element selected from the group consisting of Nb and Ta are subjected to solid solution substitution. The dielectric ceramic composition according to any one of claims 1 to 5, wherein a main phase is a ZrTiO ₄ phase. 7. In the first component, 0.5 ≦ a / b
7. The dielectric ceramic composition according to claim 6, wherein ≤1.9. Here, a is Mg, Z which is substituted for ZrTiO ₄ by solid solution.
n is the sum of the mole fractions of at least one element selected from the group consisting of n, Co and Mn, and b is ZrTiO
₄ is the sum of the mole fractions of at least one element selected from the group consisting of Nb and Ta which are solid-solution substituted. 8. A dielectric ceramic, comprising: a dielectric ceramic; and a conductor formed so as to be in contact with the dielectric ceramic, wherein the dielectric ceramic is made of the dielectric ceramic composition according to claim 1; A dielectric device, wherein the conductor contains at least one element selected from Ag and Pd as a main component.