JP2003160377A - Dielectric ceramic composition and multilayer ceramic component using the same - Google Patents

Abstract

(57) [Summary] A low-resistance conductor such as Cu or Ag can be fired at a temperature of 800 to 1000 ° C. or less, and can have a low dielectric loss tan δ (high Q).
Value), and a dielectric ceramic composition having a relative dielectric constant ε _r of about 8 to 30 so that the absolute value of the temperature coefficient τ _f of the resonance frequency is small and a multilayer ceramic part or the like can be formed to an appropriate size. provide. A general formula _{x (Zn 2 TiO 4) -} (1-x)
The present invention relates to a dielectric ceramic composition containing 5 to 150 parts by weight of a glass component with respect to 100 parts by weight of a main component represented by TiO ₂ and x in the range of 0.5 ≦ x <1.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a dielectric ceramic composition which can be co-fired with low resistance conductors such as Au, Ag and Cu and has a low dielectric loss (high Q value) suitable for laminated ceramic parts. , And a monolithic ceramic component such as a monolithic ceramic capacitor and an LC filter using the same. In particular, it relates to a dielectric ceramic composition composed of Zn ₂ TiO ₄ , TiO ₂ and a glass component, and a laminated ceramic component using the same.

[0002]

2. Description of the Related Art In recent years, with the integration of microwave circuits,
There is a demand for a compact dielectric resonator having a small dielectric loss (tan δ) and stable dielectric characteristics. The dielectric ceramic composition used for such a dielectric resonator has a relatively large relative permittivity ε _r , a large unloaded Q value, and a small temperature coefficient τ _f of the resonance frequency. Is required. Generally, the larger the relative permittivity ε _r , the smaller the resonator, but the higher the resonance frequency, the smaller the resonator. However, if the resonator becomes too small, the processing accuracy will decrease and it will be easily affected by the printing accuracy of the electrodes.Therefore, the relative permittivity ε _r should be within an appropriate range so that the resonator does not become too small depending on the application. Things are required.
The present invention relates to a dielectric ceramic composition having a relative dielectric constant ε _r of about 8 to 30.

As a dielectric ceramic composition of this type, BaO
-MgO-WO ₃ based material _{(JP-A-6-236708), Al 2 O 3 -TiO} 2 -Ta 2 O 5 based materials (JP-A 9-52760 JP) have been proposed.

[0004]

Recently, multilayer ceramic parts such as multilayer ceramic capacitors and LC filters in which dielectric ceramic compositions are laminated have been developed, and the dielectric ceramic composition and internal electrodes are laminated by simultaneous firing. Is being implemented. However, since the firing temperature of the dielectric porcelain composition is as high as 1300 to 1400 ° C., it is difficult to perform the firing with the internal electrode at the same time, and in order to form a laminated structure, palladium which can withstand high temperature as an electrode material is used. (Pd)
It was limited to materials such as platinum and platinum (Pt). For this reason,
Low resistance conductor and cheap silver (Ag), A as electrode material
There is a demand for a dielectric ceramic composition that can be co-fired at a low temperature of 1000 ° C. or lower using g-Pd, Cu and the like.

An object of the present invention is to make a low resistance conductor such as Cu or Ag co-fired so that the interior and the multilayer structure can be realized.
Can be fired at a temperature of up to 1000 ° C, has a low dielectric loss tan δ (high Q value), has a small absolute value of the resonance frequency temperature coefficient τ _f , and forms a multilayer ceramic component or the like in an appropriate size. So that the relative permittivity ε _r is 8 to 3
It is to provide a dielectric ceramic composition of about 0. Further, a dielectric layer made of such a dielectric ceramic composition and C
It is an object of the present invention to provide a monolithic ceramic component such as a monolithic ceramic capacitor or an LC filter having an internal electrode containing u or Ag as a main component.

[0006]

Means for Solving the Problems The inventors of the present invention have made earnest studies to solve the above problems in conventional dielectric ceramic materials, and as a result, found that the following compositions satisfy the above requirements. I found it.

The present invention has the general formula x (Zn ₂ TiO ₄ )-
(1-x) TiO ₂ , wherein 5 parts by weight or more and 150 parts by weight or less of the glass component is contained with respect to 100 parts by weight of the main component having x in the range of 0.50 ≦ x <1. And a dielectric ceramic composition.

As the glass component, PbO-based glass is used.
Glass, ZnO glass, SiO_TwoGlass or Pb
O, ZnO, Bi_TwoO_Three, BaO, B_TwoO_Three, Si
O_Two, ZrO _Two, TiO_Two, Al_TwoO_Three, CaO, Sr
Gas composed of two or more metal oxides selected from the group of O
It is preferably lath.

Further, the present invention provides a laminated ceramic component including a plurality of dielectric layers, internal electrodes formed between the dielectric layers, and external electrodes electrically connected to the internal electrodes, wherein the dielectric The body layer is composed of a dielectric ceramic obtained by firing the dielectric ceramic composition, and the internal electrode is C
The present invention relates to a monolithic ceramic component which is formed of u alone or Ag alone or an alloy material containing Cu or Ag as a main component.

By using a specific composition of Zn ₂ TiO ₄ and TiO ₂ and a glass component, at a firing temperature of 1000 ° C. or less, the relative dielectric constant ε _r is about 8 to 30, the dielectric loss is small, and the resonance frequency is low. Absolute value of temperature coefficient of 60p
It can be pm / ° C. or less. This also allows
It is possible to provide a monolithic ceramic component having Cu or Ag alone or an internal electrode containing Cu or Ag as a main component.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The dielectric ceramic composition of the present invention will be specifically described below. The dielectric ceramic composition of the present invention has the general formula x (Zn ₂ TiO ₄ )-(1-x) TiO ₂
, And x is within the range of 0.5 ≦ x <1 1
5 parts by weight or more and 150 parts by weight of glass component per 100 parts by weight
It is characterized by containing less than or equal to parts by weight.

If x is less than 0.5 in the above composition, τ _f becomes +60 ppm / ° C. or more, which is not preferable.
In addition, the dielectric ceramic composition of the present invention contains 5 parts by weight of the glass component with respect to 100 parts by weight of the main component serving as the ceramic base material.
If it is less than part by weight, the firing temperature becomes high, and if it exceeds 150 parts by weight, the glass tends to elute and react with the setter.

Zn ₂ TiO ₄ used in the present invention can be obtained by mixing zinc oxide ZnO and TiO ₂ in a molar ratio of 2: 1 and firing. As a raw material of Zn ₂ TiO ₄ , besides TiO ₂ and ZnO, nitrates, carbonates, hydroxides, chlorides, which become oxides during firing, and organometallic compounds may be used.

The dielectric ceramic composition of the present invention is characterized by containing a predetermined amount of glass. Here, the glass is an amorphous solid substance, which is obtained by melting. Crystallized glass including partially crystallized glass is also included in the glass. The solid substance may be an inorganic substance made of an oxide, and the glass used in the present invention may be a PbO type glass, a ZnO type glass, a SiO ₂ type glass, or a glass made of another metal oxide. P
The bO-based glass is a glass containing PbO and contains PbO.
_{O-SiO 2, PbO-B} 2 O 3, or glass containing _{PbO-P 2 O 5, R} 2 O-PbO-SiO 2, R 2 O
_{-CaO-PbO-SiO 2, R} 2 O-ZnO-PbO
_{-SiO 2, R 2 O-Al} 2 O 3 -PbO-SiO 2 glass (however, where R is _Na 2 _{O, K} 2 O) containing the like are exemplified. ZnO-based glass is a glass containing _{ZnO, ZnO-Al 2 O 3} -BaO-Si
_{O 2, ZnO-Al 2 O} 3 -R 2 O-SiO 2, etc. are exemplified. SiO ₂ glass is a glass containing _{SiO 2, SiO 2 -Al 2 O} 3 -R 2 O, SiO
₂ -Al ₂ O ₃ -BaO, etc. are exemplified.

Further, as the glass used in the present invention,
In addition to PbO-based glass, ZnO-based glass, and SiO ₂ -based glass, glasses made of various metal oxides can also be used, and PbO, ZnO, Bi ₂ O ₃ , BaO, B ₂ O can be used.
₃ , SiO ₂ , ZrO ₂ , TiO ₂ , Al ₂ O ₃ , Ca
Glass made of two or more kinds of metal oxides selected from the group consisting of O and SrO is also used. As the glass, either amorphous glass or crystalline glass may be used. When PbO is contained, the firing temperature tends to decrease, but the unloaded Q value tends to decrease, and the content of PbO component in the glass is 4
It is preferably 0% by weight or less. In addition, glass containing SiO ₂ and Al ₂ O ₃ components at the same time in the glass (that is, SiO ₂ −
Al ₂ O ₃ based glass) is particularly suitable as the glass used in the present invention. In particular, according to the present invention, _ZnO-Al 2 _{O 3}
-BaO-SiO ₂ is preferable from the viewpoint that it is possible to obtain a high unloaded Q value.

According to the invention, the general formula x (Zn ₂ TiO _2
4 )-(1-x) TiO ₂ and x is 0.5 ≦ x <
By including 5 parts by weight or more and 150 parts by weight or less of the glass component with respect to 100 parts by weight of the main component within the range of 1, it is possible to perform low-temperature sintering at a firing temperature of 800 to 1000 ° C. and a relative dielectric constant ε. _r is about 8 to 30, the unloaded Q value is large, and the temperature coefficient τ _f of the resonance frequency is ± 60 ppm / ° C.
It is possible to obtain a dielectric porcelain composition having the property of being within.

In the present invention, Zn ₂ TiO ₄ , T before firing is used.
The io ₂ and glass particles are individually crushed and mixed, or each particle is crushed after mixing, but the average particle size of these raw material particles before firing is less than 5 μm, preferably 1 μm or less. Further, low temperature firing becomes possible. If the average particle size is made too small, it may be difficult to handle. Therefore, the average particle size is preferably 0.05 μm or more.

Next, a method for producing the dielectric ceramic composition of the present invention will be described. First, titanium oxide and zinc oxide are weighed in a predetermined ratio and wet-mixed with a solvent such as water or alcohol. Then, after removing water, alcohol, etc., the product is crushed and then crushed in an oxygen-containing atmosphere (for example, air atmosphere) to 90
Calcination is performed at 0 to 1200 ° C. for about 1 to 5 hours. The calcined powder thus obtained is Zn ₂ TiO ₄ . The Zn ₂ TiO ₄ , TiO ₂ and glass are weighed in a predetermined ratio and wet mixed with a solvent such as water or alcohol.
Then, after removing water, alcohol, etc., it grind | pulverizes and produces raw material powder.

The dielectric properties of the dielectric ceramic composition of the present invention are evaluated by the shape of pellets. Specifically, the raw material powder is mixed with an organic binder such as polyvinyl alcohol, homogenized, dried and pulverized, and then pressure-molded into a pellet shape (pressure 100 to 1000 kg / cm ² ). The obtained molded product is fired at 800 to 1000 ° C. in an oxygen-containing gas atmosphere such as air to obtain Zn ₂
It is possible to obtain a dielectric ceramic composition in which a TiO ₄ phase, a TiO ₂ phase and a glass phase coexist.

The thus-obtained dielectric ceramic composition is processed into various shapes and sizes as required, or is formed into a sheet by a doctor blade method or the like, and laminated with a sheet and an electrode to obtain various laminated ceramic parts. It can be used as a material. Examples of the monolithic ceramic parts include monolithic ceramic capacitors, LC filters, dielectric resonators and dielectric substrates.

The multilayer ceramic component of the present invention comprises a plurality of dielectric layers, internal electrodes formed between the dielectric layers, and external electrodes electrically connected to the internal electrodes.
The dielectric layer is made of a dielectric ceramic obtained by firing the dielectric ceramic composition, and the internal electrodes are made of Cu simple substance or Ag simple substance, or an alloy material containing Cu or Ag as a main component. ing. The multilayer ceramic component of the present invention comprises a dielectric layer containing a dielectric ceramic composition and Cu.
It is obtained by co-firing a simple substance or a simple substance of Ag, or an alloy material containing Cu or Ag as a main component.

As an embodiment of the above-mentioned laminated ceramic component, for example, a triplate type resonator shown in FIG. 1 can be cited. FIG. 1 is a perspective view showing a triplate type resonator according to one embodiment of the present invention. As shown in FIG. 1, the triplate-type resonator includes a plurality of dielectric layers, an internal electrode 2 formed between the dielectric layers, and an external electrode 3 electrically connected to the internal electrode. It is a multilayer ceramic component provided. The triplate type resonator is
It is obtained by stacking a plurality of dielectric ceramic layers 1 with the internal electrode 2 arranged in the central portion. The internal electrode 2 is formed so as to penetrate from the first surface A shown in FIG. 1 to the second surface B opposite thereto, and only the first surface A is an open surface,
The external electrodes 3 are formed on the five surfaces of the resonator except the first surface A, and the internal electrodes 2 and the external electrodes 3 are formed on the second surface B.
Are connected. The material of the internal electrode 2 is Cu or A
g, or these are the main components. Since the dielectric ceramic composition of the present invention can be fired at a low temperature, these internal electrode materials can be used.

[0023]

Example 1 0.33 mol of titanium oxide (TiO ₂ ) and zinc oxide (Zn)
0.66 mol of O) was put in a ball mill together with ethanol and wet-mixed for 12 hours. After the solution was desolvated, it was pulverized and calcined at 1000 ° C. in an air atmosphere to obtain a Zn ₂ TiO ₄ calcined powder. Table 1 shows the Zn ₂ TiO ₄ calcined powder and TiO _2.
The material prepared with the compounding amount shown in was used as the base material. 52% by weight of ZnO, Si based on 100 parts by weight of the base material
O ₂ 6 wt%, Al ₂ O ₃ 12 wt%, B ₂ O ₃
What was added with 10 parts by weight of glass powder composed of 30% by weight was put into a ball mill and wet-mixed for 24 hours.
After desolvation of the solution, the raw material particles were pulverized until the average particle size became 1 μm, an appropriate amount of polyvinyl alcohol solution was added to the pulverized product, and the mixture was dried, and then formed into pellets having a diameter of 12 mm and a thickness of 4 mm, and the pellet was placed in an air atmosphere It was baked at 900 ° C. for 2 hours. The X-ray diffraction diagram of the produced sintered body is shown in FIG. As shown in FIG. 2, it can be seen that the Zn ₂ TiO ₄ phase and the TiO ₂ phase coexist also in the sintered body of the dielectric ceramic composition of the present invention.

The dielectric ceramic composition thus obtained was processed into a size having a diameter of 7 mm and a thickness of 3 mm and then subjected to an unloaded Q at a resonance frequency of 7 to 11 GHz by a dielectric resonance method.
The value, the relative permittivity ε _r, and the temperature coefficient τ _f of the resonance frequency were obtained. The results are shown in Table 2.

[0025]

[Table 1]

[0026]

[Table 2]

100 g of a mixture of the base material and glass
On the other hand, 9 g of polyvinyl butyral as a binder, 6 g of dibutyl phthalate as a plasticizer, 60 g of toluene as a solvent and 30 g of isopropyl alcohol were added, and a green sheet having a thickness of 100 μm was prepared by a doctor blade method. And this green sheet, 65
Twenty-two layers were laminated by thermocompression bonding with a pressure of 200 kg / cm ² at a temperature of ° C. At that time, the layer printed with Ag as the internal electrode was arranged so as to come to the central portion in the thickness direction.
The obtained laminate was fired at 900 ° C. for 2 hours, and then an external electrode was formed to produce a triplate type resonator. The size is 4.9 mm in width, 1.7 mm in height, and 8.4 mm in length.

The obtained triplate-type resonator is
The unloaded Q value was evaluated at a resonance frequency of 2 GHz. That
As a result, the firing temperature was 900 ° C, the shrinkage rate was 19%, and the relative dielectric
Rate ε _rIs 21, the temperature coefficient τ of the resonance frequency_fIs 0 ppm / ° C
The unloaded Q was 210. Thus, according to the present invention,
By using the dielectric ceramic composition
A triplate-type resonator having is obtained.

Examples 2 to 4 Zn ₂ TiO ₄ and TiO ₂ are shown in Table 1 as in Example 1 above.
A base material was obtained by mixing in the compounding amounts shown in Table 1. After mixing the base material and glass in the compounding amounts shown in Table 1, a pellet-shaped sintered body was prepared under the same conditions as in Example 1 and Various properties were evaluated in the same manner as in Example 1. The results are shown in Table 2.

Examples 5 to 9 As in Example 1 above, Zn ₂ TiO ₄ and TiO ₂ are shown in Table 1.
A base material was obtained by mixing in the compounding amounts shown in Table 1. After mixing the base material and glass in the compounding amounts shown in Table 1, a pellet-shaped sintered body was prepared under the same conditions as in Example 1 and Various properties were evaluated in the same manner as in Example 1. The results are shown in Table 2.

Examples 10 to 14 Table 1 shows Zn ₂ TiO ₄ and TiO ₂ as in Example 1 above.
A base material was obtained by mixing in the compounding amounts shown in Table 1. The base material and various glasses shown in Table 1 were mixed in the compounding amounts shown in Table 1, and pelletized sintered bodies were prepared under the same conditions as in Example 1. Was manufactured, and various characteristics were evaluated by the same method as in Example 1.
The results are shown in Table 2.

Examples 15 and 16 Zn ₂ TiO ₄ and TiO ₂ are shown in Table 1 as in Example 1 above.
As a base material, the base material is mixed with the compounding amounts shown in Table 1. After mixing the base material and various glasses shown in Table 1 with the compounding amounts shown in Table 1, until the particle size reaches the average particle size shown in Table 1. Crush,
A pellet-shaped sintered body was produced under the same conditions as in Example 1, and various characteristics were evaluated in the same manner as in Example 1. The results are shown in Table 2.

Comparative Examples 1 to 4 Zn ₂ TiO ₄ and TiO ₂ are shown in Table 1 as in Example 1 above.
The glass having the compounding amount shown in Table 1 was used as a base material, the glass shown in Table 1 was mixed with the compounding amount shown in Table 1, and a pellet-shaped sintered body was produced under the same conditions as in Example 1. However, if the amount of glass added is less than 5 parts by weight with respect to 100 parts by weight of the base material, sintering cannot be performed below 1000 ° C.
If it was not raised to 0 ° C., it could not be densified. On the other hand, when the amount exceeded 150 parts by weight, the glass was eluted and reacted with the setter, and a good sintered body could not be obtained. The results are shown in Table 2.

Comparative Examples 5 to 7 As in Example 1 above, Zn ₂ TiO ₄ and TiO ₂ are shown in Table 1.
A base material was obtained by mixing in the compounding amounts shown in Table 1. After mixing the base material and glass in the compounding amounts shown in Table 1, pellet-shaped sintered bodies were produced under the same conditions as in Example 1. However, under the condition of x <0.5, the temperature coefficient τ _f of the resonance frequency is +6.
It became 0 ppm / ° C or higher. The results are shown in Table 2.

[0035]

According to the dielectric ceramic composition of the present invention, the relative permittivity ε _r is 8 to 30, the unloaded Q value is large,
Moreover, it is possible to provide a dielectric ceramic composition having a small temperature coefficient τ _{f of} resonance frequency within ± 60 ppm / ° C.
Further, since the firing can be performed at a temperature of 1000 ° C. or less, the power cost required for firing can be reduced and Cu alone or A
It is possible to co-fire with a low-resistance conductor made of a simple substance of g or an alloy material containing Cu or Ag as a main component, and it is possible to provide a laminated component using this as an internal electrode.

[Brief description of drawings]

FIG. 1 is an example of a monolithic ceramic component according to the present invention.

2 is an X-ray diffraction diagram of a sintered body of the dielectric ceramic composition according to the present invention obtained in Example 1. FIG.

[Explanation of symbols]

1 Dielectric ceramic layer 2 internal electrodes 3 external electrodes

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01B 3/12 304 H01B 3/12 304 H01G 4/12 358 H01G 4/12 358 361 361 (72) Inventor Koichi Fukuda Yamaguchi 5 1978, Koji, Ube City, Ube Pref. F-term inside Ube Research Center, Ube Industries Ltd. (reference) 4G031 AA04 AA05 AA06 AA11 AA12 AA26 AA28 AA29 AA30 AA32 AA35 BA09 CA01 CA08 GA01 GA04 GA06 GA09 GA11 4G062 AA08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A08 A 08 A 08 A 08 A 08 A 08 A 08 A 08 A 08 A 08 A 0 DA06 DB03 DB04 DC04 DC05 DD01 DE01 DE04 DE05 DE06 DF01 DF02 DF03 DF04 EA01 EB01 EC01 ED01 EE01 EF01 EG01 FA01 FB01 FC01 FD01 FE01 FF01 FG01 FH01 FJ01 FK01 FL01 GA01 GA10 GB01 GC01 GD01 GE01 HH01 HH03 HH05 HH07 HH09 HH11 HH13 HH15 HH17 HH20 JJ01 JJ03 JJ05 JJ07 JJ10 KK01 KK03 KK05 KK07 KK10 MM13 MM27 MM31 NN26 NN32 NN34 PP04 5E001 AC09 AE02 AE03 AF03 AH01 AH09 AJ01 AJ02 5G303 AA01 AB06 AB07 AB08 AB11 BA12 CA03 CB01 CB02 CB03 CB05 CB06 CB25 CB30 CB32 CB35 CB38 CB39

Claims (3)

[Claims] 1. The general formula x (Zn ₂ TiO ₄ )-(1-
x) A dielectric material containing 5 parts by weight or more and 150 parts by weight or less of a glass component with respect to 100 parts by weight of a main component represented by TiO ₂ and x falling within a range of 0.5 ≦ x <1. Body porcelain composition. 2. The glass component is PbO-based glass, Z
nO glass, SiO_TwoGlass, PbO, Zn
O, Bi_TwoO_Three, BaO, B_TwoO_Three, SiO _Two, ZrO
_Two, TiO_Two, Al_TwoO_Three, CaO, SrO
Selected from glasses consisting of two or more selected metal oxides
1. At least one of the following:
The dielectric ceramic composition described. 3. A multilayer ceramic component comprising a plurality of dielectric layers, internal electrodes formed between the dielectric layers, and external electrodes electrically connected to the internal electrodes, wherein the dielectric layers are A dielectric porcelain obtained by firing the dielectric porcelain composition according to claim 1 or 2, wherein the internal electrodes are Cu simple substance or Ag simple substance, or Cu or A.
A monolithic ceramic part formed of an alloy material containing g as a main component.