JP2003277136A - Dielectric ceramic composition and multilayer ceramic electronic parts - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a dielectric ceramic composition which is suitable for composing a dielectric ceramic layer of a multilayer ceramic capacitor, has the satisfactory temperature properties of a dielectric constant, a reduced change in capacitance to d.c. voltage, has high reliability and is not made into a semiconductor even when fired in a reducing atmosphere. <P>SOLUTION: The dielectric ceramic composition is expressed by the general formula of (Ba<SB>1-x</SB>Ca<SB>x</SB>)<SB>m</SB>TiO<SB>3</SB>+α<SB>1</SB>BaO+α<SB>2</SB>CaO+-βMnO+γMgO+δSiO<SB>2</SB>+εLi<SB>2</SB>O; wherein, 0.04≤x≤0.20, 1.035<m+α<SB>1</SB>+α<SB>2</SB>≤1.07, 0.990≤m, 0.0001≤β≤0.05, 0.0001≤γ≤0.025, 0.002≤δ≤0.08, and 0.001≤ε≤0.05. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric ceramic composition and a monolithic ceramic electronic component such as a monolithic ceramic capacitor formed by using the dielectric ceramic composition. The present invention relates to an improvement for improving the temperature characteristic of the permittivity of a dielectric ceramic layer and advantageously improving the reliability.

[0002]

2. Description of the Related Art A monolithic ceramic capacitor, which is an example of a monolithic ceramic electronic component, has a state in which a plurality of laminated dielectric ceramic layers and internal electrodes formed along a specific interface between the dielectric ceramic layers are laminated. It has a laminated body. In such a monolithic ceramic capacitor, recently, in order to reduce the cost, an inexpensive base metal N, instead of an expensive noble metal such as Ag or Pd, has been used as a metal for providing a conductive component contained in the internal electrodes.
i is often used.

Further, when manufacturing a monolithic ceramic capacitor, a step of firing the above-mentioned green laminated body is carried out. As described above, when Ni or the like is used for the internal electrodes, it is necessary to apply a reducing atmosphere in which Ni or the like is not oxidized in this firing step. However, by firing in a reducing atmosphere, a ceramic made of barium titanate, for example, is usually reduced and becomes a semiconductor.

In order to solve this problem, for example, as shown in Japanese Patent Publication No. 57-42588, by making the barium site / titanium site ratio in the solid solution of barium titanate excessive than the stoichiometric ratio, Techniques for non-reduction of dielectric ceramic materials have been developed. Since then, it has become possible to put into practical use a monolithic ceramic capacitor that uses Ni or the like as an internal electrode, and its production volume is expanding.

[0005]

With the recent development of electronics technology, miniaturization of electronic parts has rapidly progressed, and the tendency of monolithic ceramic capacitors to be miniaturized and to have a large capacity has become remarkable. .

Further, in particular, for a monolithic ceramic capacitor, not only the above-mentioned increase in capacitance but also the temperature stability of capacitance is required, and as a high dielectric constant ceramic material having good temperature characteristics, Many materials have been proposed and put into practical use.

All of these materials have BaTiO ₃ as a main component, and the additive component is diffused into the BaTiO ₃ particles in the process of adding a rare earth element to this and sintering. It is known that the individual particles of the obtained sintered body have a core-shell structure composed of a core part in which an additive component is not diffused and a shell part in which an additive component is diffused. , The core part and the shell part are given by superposition of temperature characteristics of different dielectric constants.

By providing such a material, a monolithic ceramic capacitor having a small capacitance variation with temperature and a high capacitance is realized, which contributes to the market expansion.

However, the above-mentioned core-shell structure is
This is achieved by controlling the diffusion of additive components during the sintering process of ceramics. Therefore, if the additive components are excessive, flat temperature characteristics cannot be obtained. On the other hand, if the diffusion of the added component is insufficient, the reliability is poor. Therefore, when industrially mass-producing, it is relatively difficult to realize stable control of sintering and diffusion of additive components with the above-mentioned materials, and the temperature characteristic of the obtained dielectric constant is also relatively unstable. .

Further, in order to meet the above-mentioned demands for miniaturization and large capacity of the monolithic ceramic capacitor, it has become necessary to make the dielectric ceramic layers included in the laminate thinner and multilayer.

However, when the layer is thinned, the number of ceramic particles between the internal electrodes is reduced and the reliability is remarkably deteriorated. Therefore, there is a demand for the development of a material which has a small particle size of the ceramic particles and thereby has high reliability and excellent stability of the electric field strength of the dielectric constant.

However, in the conventional material having the core-shell structure, when the particle size of the ceramic particles is reduced, the diffusion of the additive component increases, and it becomes relatively difficult to secure the flat temperature characteristic.

From the above, it is practically difficult or impossible to achieve a sufficiently thin layer of the monolithic ceramic capacitor and a sufficient stabilization of the dielectric constant up to a high temperature while using a material having a core-shell structure. The current situation is possible.

The same applies not only to the above-mentioned monolithic ceramic capacitor but also to other monolithic ceramic electronic parts.

Therefore, an object of the present invention is to provide a dielectric ceramic composition and a monolithic ceramic electronic component constituted by using the dielectric ceramic composition, which can solve the above-mentioned problems. is there.

[0016]

Briefly, the dielectric ceramic composition according to the present invention is a material having no core-shell structure due to diffusion of an additive component, and therefore, with respect to the temperature characteristics and reliability of the dielectric constant. The material is not easily affected by firing conditions. Further, when a dielectric ceramic composition according to the present invention is used to manufacture, for example, a multilayer ceramic capacitor, it is necessary to satisfy the X7R characteristic defined by the EIA standard with respect to the temperature characteristic of capacitance even when the layer is thinned. Therefore, the rate of change of the capacitance with respect to the DC voltage is small, and high reliability can be realized.

More specifically, the dielectric cell according to the present invention is
The Lamic composition has the general formula: (Ba _1-xCa_x)_mTi
O₃+ Α₁BaO + α₂CaO + βMnO + γMgO +
δSiO₂+ ΕLi₂Represented by O, and 0.
04 ≦ x ≦ 0.20, 1.035 <m + α₁+ Α₂≤
1.07, 0.990 ≦ m, 0.0001 ≦ β ≦ 0.0
5, 0.0001 ≦ γ ≦ 0.025, 0.002 ≦ δ ≦
0.08 and 0.001 ≦ ε ≦ 0.05
It is characterized by adding.

The present invention is also directed to a monolithic ceramic electronic component comprising a laminate including a plurality of laminated dielectric ceramic layers and internal electrodes formed along specific interfaces between the dielectric ceramic layers. To be In this laminated ceramic electronic component, the dielectric ceramic layer is
It is characterized by comprising the dielectric ceramic composition as described above.

The internal electrodes described above preferably contain nickel or a nickel alloy.

In the laminated ceramic electronic component according to the present invention, an external electrode electrically connected to the internal electrode is formed on the outer surface of the above-mentioned laminated body, and the external electrode is
It is preferable to provide a sintered layer including a sintered body of conductive metal powder.

Further, in such a monolithic ceramic electronic component, the external electrode may include at least one plating layer formed on the above-mentioned sintered layer.

The present invention is particularly advantageously applied to laminated ceramic capacitors. In this case, a plurality of internal electrodes are formed so as to face each other via a dielectric ceramic layer so as to form a capacitance, and the external electrodes are electrically connected to a specific one of the internal electrodes. It is formed.

[0023]

FIG. 1 is a sectional view schematically showing a monolithic ceramic capacitor 1 as an example of a monolithic ceramic electronic component formed by using a dielectric ceramic composition according to the present invention.

The monolithic ceramic capacitor 1 constitutes a chip-shaped electronic component having a rectangular parallelepiped shape as a whole, and includes a laminate 2 which is a component body. Laminate 2
Is composed of a plurality of laminated dielectric ceramic layers 3 and a plurality of internal electrodes 4 and 5 respectively formed along a plurality of specific interfaces between the plurality of dielectric ceramic layers 3. The internal electrodes 4 and 5 are formed so as to reach the outer surface of the laminated body 2, but the internal electrode 4 and the other end surface 7 that are drawn out to one end face 6 of the laminated body 2.
The internal electrodes 5 drawn out up to the above are alternately arranged inside the laminated body 2.

External electrodes 8 and 9 are formed on the outer surfaces of the laminate 2 and on the end faces 6 and 7, respectively. The external electrodes 8 and 9 include sintered layers 10 and 11 formed on the end faces 6 and 7 and containing a sintered body of conductive metal powder. Further, if necessary, the sintered layer 10
And 11 are formed with first plating layers 12 and 13 made of nickel, copper, etc., respectively, and second plating layers 14 and 15 made of solder, tin, etc. are formed thereon, respectively. .

Next, a method for manufacturing the above-mentioned monolithic ceramic capacitor 1 will be described in the order of manufacturing steps.

First, a dielectric ceramic raw material powder is prepared, made into a slurry, and this slurry is formed into a sheet to obtain a ceramic green sheet for the dielectric ceramic layer 3. Here, as the dielectric ceramic raw material powder, as will be described in detail later, the raw material powder for the dielectric ceramic composition according to the present invention is used.

Next, the internal electrodes 4 and 5 are formed on each one main surface of the specific one of the ceramic green sheets. The internal electrodes 4 and 5 are made of nickel, nickel alloy,
It contains a base metal such as copper or a copper alloy, or a noble metal such as silver, palladium, or a silver-palladium alloy as a conductive component, and particularly preferably contains nickel or a nickel alloy. The internal electrodes 4 and 5 are usually formed by a printing method such as a screen printing method or a transfer method using a conductive paste containing a conductive component as described above. Good.

Next, a required number of ceramic green sheets for the dielectric ceramic layer 3 on which the internal electrodes 4 or 5 are formed are laminated, and an appropriate number of these ceramic green sheets are formed without the internal electrodes. The raw laminate is obtained by pressing them with a state of being sandwiched by.

Next, this raw laminated body is fired at a prescribed temperature in a prescribed reducing atmosphere to obtain a sintered laminated body 2 as shown in FIG.

Then, outer electrodes 8 and 9 are formed on both end surfaces 6 and 7 of the laminate 2 so as to be electrically connected to specific ones of the inner electrodes 4 and 5. As the conductive material of the sintered layers 10 and 11 provided on the external electrodes 8 and 9, the same conductive material as that of the internal electrodes 4 and 5 can be used. The sintered layers 10 and 11 are usually made of a conductive metal powder made of B ₂ O ₃ —SiO ₂ —BaO system or L.
It is formed by applying a conductive paste obtained by adding a glass frit such as i ₂ O—SiO ₂ —BaO system and baking it.

The conductive paste to be the sintered layers 10 and 11 is usually applied to the laminated body 2 after sintering and baked as described above, but applied to the raw laminated body before baking. However, it may be baked at the same time as the firing for obtaining the laminated body 2.

Next, on each of the sintered layers 10 and 11,
First plating layer 10 by plating nickel, copper, etc.
And 11 are formed. Finally, the first plating layers 10 and 11 are plated with solder, tin or the like to form the second plating layers 12 and 13 to complete the monolithic ceramic capacitor 1.

In such a monolithic ceramic capacitor, the dielectric ceramic layer 3 has the general formula: (Ba _1-x Ca _x ) _m TiO ₃ + α ₁ BaO + α _{2 as described above.}
CaO + βMnO + γMgO + δSiO ₂ + εLi ₂ O
And is composed of a dielectric ceramic composition.

However, this dielectric ceramic composition is
In the above general formula, 0.04 ≦ x ≦ 0.20, 1.035 <m + α ₁ + α ₂ ≦ 1.07, 0.990 ≦ m, 0.0001 ≦ β ≦ 0.05, 0.0001 ≦ γ It satisfies the conditions of ≦ 0.025, 0.002 ≦ δ ≦ 0.08, and 0.001 ≦ ε ≦ 0.05.

This dielectric ceramic composition can be sintered without becoming a semiconductor even when fired in a reducing atmosphere. Further, when the dielectric ceramic composition is used to form the dielectric ceramic layer 3 of the multilayer ceramic capacitor 1 as described above, the temperature characteristic of the capacitance is X7R characteristic (-) specified by the EIA standard. 55
The change in capacity is within ± 15% at ℃ to +125 ℃),
The rate of change of the capacitance with respect to the DC voltage is small, the insulation resistance is high, and the reliability can be high.

Starting materials for such a dielectric ceramic composition are: a compound represented by (Ba _1-x Ca _x ) _m TiO ₃ ; a Ba compound; a Ca compound; and a Mn compound.
Although it contains a Mg compound, a Si compound, and a Li compound, the method for producing the raw material powder of the dielectric ceramic composition can realize the compound represented by (Ba _1-x Ca _x ) _m TiO _3. If so, any method may be adopted.

For example, (Ba _1-x Ca _x ) _m TiO ₃
The compounds represented by are BaCO ₃ , TiO _2, and CaC.
It can be obtained by a step of mixing O ₃ and a step of reacting BaCO ₃ , TiO ₂ and CaCO ₃ by heat-treating this mixture.

In addition, the compound represented by (Ba _1-x Ca _x ) _m TiO ₃ can also be obtained by a hydrothermal synthesis method, a hydrolysis method, or a wet synthesis method such as a sol-gel method.

Then, the compound represented by (Ba _1-x Ca _x ) _m TiO ₃ and the additive components Ba, Ca, M
A raw material powder for the dielectric ceramic composition can be obtained by mixing, for example, each oxide of n, Mg, Si, and Li and heat-treating them.

The additive components Ba, Ca, Mn,
As the compounds of Mg, Si and Li, in addition to using the oxide powder as described above, a solution of alkoxide or organic metal or carbonic acid can be used as long as it can form the dielectric ceramic composition as described above. Compound powder may be used, and depending on the form of the additive components used,
The properties of the obtained dielectric ceramic composition are not impaired.

The dielectric ceramic composition according to the present invention is fired to form the dielectric ceramic layer 3 of the monolithic ceramic capacitor 1 shown in FIG. In such a firing step, a metal such as nickel, nickel alloy, copper, copper alloy, silver, palladium or silver-palladium alloy contained in the internal electrodes 4 and 5 may diffuse into the dielectric ceramic layer 3. is there. However, according to the dielectric ceramic composition of the present invention, it has been confirmed that even if such a metal component is diffused, its electrical characteristics are not substantially affected.

Next, the present invention will be described more specifically based on experimental examples. This experimental example also serves as a basis for limiting the composition range according to the present invention.

In this experimental example, a monolithic ceramic capacitor as shown in FIG. 1 was produced.

First, as a starting material, high-purity Ti
O ₂ , BaCO ₃ and CaCO ₃ were prepared, and the content of Ca as shown in Table 1 below, ie, “Ca modification amount:
x ”and“ (Ba, Ca) / Ti ratio: m ”, and then mixed and pulverized. After drying, add 10 to each powder.
It is heated at a temperature of 00 ° C. or higher, whereby the average particle size of 0.20 μm of each of the types A to I (Ba _1-x
A Ca _x ) _m TiO ₃ powder was synthesized.

[0046]

[Table 1]

Further, BaCO ₃ powder, CaCO ₃ powder,
MgCO ₃ powder, MnCO ₃ powder, Si ₂ O powder and Li ₂ O powder were prepared.

Next, using these raw material powders, the raw material powders were blended so as to have the compositions shown in Tables 2 and 3 to obtain a blend.

[0049]

[Table 2]

[0050]

[Table 3]

Next, the compositions of the respective samples shown in Tables 2 and 3 were heat-treated at a temperature of 1000 to 1050 ° C. for 2 hours to obtain calcined products.

Next, a polyvinyl butyral binder and an organic solvent such as ethanol were added to each calcined product, and the mixture was wet-mixed by a ball mill to prepare a ceramic slurry.

Next, the ceramic slurry was formed into a sheet by the doctor blade method and had a thickness of 2.8 μm.
To obtain a rectangular ceramic green sheet.

Next, a conductive paste containing nickel as a main component was printed on the ceramic green sheet to form a conductive paste film to be an internal electrode.

Next, a plurality of ceramic green sheets were laminated so that the drawn-out sides of the above-mentioned conductive paste film were staggered to obtain a raw laminate.

Next, the green laminate was heated in a nitrogen atmosphere to a temperature of 350 ° C. to burn the binder, and then the H ₂ —N ₂ — with an oxygen partial pressure of 10 ⁻⁹ to 10 ⁻¹² MPa was used. H
_{In a} reducing atmosphere consisting of ₂ O gas, firing was performed at each temperature shown in Tables 4 and 5 for 2 hours to obtain a sintered laminate.

Next, on both end faces of the sintered laminated body, B
A conductive paste containing a ₂ O ₃ —SiO ₂ —BaO type glass frit and containing silver as a conductive component was applied, and baked at a temperature of 600 ° C. in a nitrogen atmosphere to be electrically connected to internal electrodes. The external electrode was formed.

The external dimensions of the monolithic ceramic capacitor thus obtained are 5.0 mm in width and 5.7 in length.
mm and the thickness was 2.4 mm, and the thickness of the dielectric ceramic layer interposed between the internal electrodes was 2.0 μm. The number of effective dielectric ceramic layers is 5, and
The counter electrode area per layer was 16.3 × 10 ⁻⁶ m ² .

The electrical characteristics of these obtained samples were measured.

Capacitance (C) and dielectric loss (tan)
δ) was measured according to JIS standard “5102” with an automatic bridge type measuring device, and the dielectric constant (ε) was calculated from the obtained capacitance.

A DC voltage of 10 V was applied for 2 minutes using an insulation resistance tester to obtain the insulation resistance (R) at 25 ° C., and the specific resistance (logρ) was calculated from this.

The rate of change in capacitance with respect to temperature change (rate of change in capacity temperature) is within the range of −55 ° C. to + 125 ° C. (ΔC ₁₂₅ /
C ₂₅ ).

Further, the rate of change of capacitance with respect to DC voltage (rate of change in capacitance electric field) is 2 when the DC voltage is not applied.
Based on the capacitance at 5 ° C, the rate of change of the capacitance (ΔC _DC4V /
C _DC0V ).

As a high temperature load test, a temperature of 150 ° C.
A direct current voltage of 20 V was applied to measure the change over time of the insulation resistance, and the time when the insulation resistance value of each sample became 10 ⁵ Ω or less was regarded as a failure, and the average failure time was calculated.

The evaluation results of the above electrical characteristics are shown in Tables 4 and 5.

[0066]

[Table 4]

[0067]

[Table 5]

The preferred ranges for the electrical characteristics shown in Tables 4 and 5 are as follows.

The dielectric constant is 1500 or more,
The dielectric loss is 3.0% or less, the capacitance temperature change rate is within ± 15%, and the capacitance electric field change rate is within an absolute value of 10%.

The specific resistance (logρ) is 1
It is 3.0 Ω · cm or more, and the average failure time is 100 hours or more.

Further, in order to evaluate the structure of the ceramic particles, the dielectric ceramic layer portion in the laminated body after firing was subjected to Ar ion milling to make it into a thin piece, which was then magnified at 400,000 times using a high resolution electron microscope. Observed at double.

In the following, the reason why the composition range is limited in the present invention will be described.

In Tables 1 to 5, the sample symbols or sample numbers marked with * are samples outside the composition range according to the present invention.

Sample 1, which is outside the scope of the present invention, is shown in Table 2
As shown in (Ba_1-xCa_x) _mTiO₃As powder
, “A” is used, and this “A” is shown in Table 1 and Table 2.
As shown in, the Ca modification amount x is 0.04 which is less than 0.04.
It is 3. Therefore, in Sample 1, as shown in Table 4,
The average failure time is as short as 10 hours.

On the other hand, similarly, in Sample 2 outside the scope of the present invention, as shown in Table 2, (Ba _1-x Ca _x ) _m T
"B" is used as the iO ₃ powder, and this "B" is
As shown in Table 1 and Table 2, the Ca modification amount x is 0.20.
Is over 0.21. Therefore, in sample 2, as shown in Table 4, the dielectric constant was as small as 1120, the capacitance temperature change rate was large as -17.2%, and the mean failure time was 80 hours, which was relatively short.

Further, in Sample 3 outside the scope of the present invention, as shown in Table 2, "C" is used as the (Ba _1-x Ca _x ) _m TiO ₃ powder, and this "C" is 1 and Table 2, the (Ba, Ca) / Ti ratio m was 0.99.
It is 0.988 which is less than 0. Therefore, in sample 3, as shown in Table 4, the average failure time was so short that it could not be measured, and the failure occurred at the moment when the voltage was applied at a high temperature.

Further, as shown in Table 2, in Samples 4 to 6 outside the scope of the present invention, as shown in Table 2, (Ba, Ca) / Ti ratio m and B
Sum of aO content α ₁ and CaO content α ₂ , ie m
+ Α ₁ + α ₂ is 1.072, which exceeds 1.07.
Therefore, in these Samples 4 to 6, sintering was insufficient, and as shown in Table 4, tan δ was larger than 3.0%, the capacity temperature change rate exceeded the range of ± 15%, and the specific resistance ( log ρ) was lower than 13.0 Ω · cm, the mean failure time was extremely short to the extent that it could not be measured, and failure occurred at the moment when voltage was applied at high temperature.

On the other hand, similarly, in Samples 7 and 8 which are outside the scope of the present invention, as shown in Table 2, m + α ₁ + α ₂
Is 1.032 or less and 1.032. Therefore, in Samples 7 and 8, as shown in Table 4, the dielectric loss was 3.0.
%, And the rate of change in capacitance electric field is 10% in absolute value.
And the mean time to failure was shortened to 40 hours and 35 hours, respectively.

Further, as shown in Table 2, in the sample 9 outside the scope of the present invention, the MnO content β was 0.0001.
It is less than 0.00005. Therefore, in sample 9,
As shown in Table 4, the specific resistance was lower than 13.0 Ω · cm, the average failure time was remarkably short so that it could not be measured, and the failure occurred at the moment when the voltage was applied at high temperature.

On the other hand, similarly, in the sample 10 outside the scope of the present invention, as shown in Table 2, the MnO content β was 0.
It is 0.06 which exceeds 05. Therefore, in sample 10, as shown in Table 4, the capacity-temperature change rate was out of the range of ± 15% and the specific resistance was also lower than 13.0 Ω · cm.

Further, as shown in Table 2, in Sample 11 outside the scope of the present invention, the MgO content γ was 0.0001.
It is less than 0.00005. Therefore, in Sample 11, as shown in Table 4, the dielectric loss is larger than 3.0%, the capacitance electric field change rate exceeds 10% in absolute value, and the specific resistance is smaller than 13.0 Ω · cm. The average failure time was so short that it could not be measured, and the failure occurred at the moment when voltage was applied at high temperature.

On the other hand, similarly, in the sample 12 outside the scope of the present invention, as shown in Table 2, the MgO content γ was 0.
It is 0.027, which exceeds 025. Therefore, sample 12
Then, the sintering was insufficient, and as shown in Table 4, the dielectric constant was as low as 950, the dielectric loss was large as 12.3%, and the capacity temperature change rate exceeded the range of ± 15%, The specific resistance was lower than 13.0 Ω · cm, the average failure time was extremely short to the extent that it could not be measured, and a failure occurred at the moment when a voltage was applied at a high temperature.

Further, as shown in Table 2, in the sample 13 outside the scope of the present invention, the SiO ₂ content δ was 0.002.
It is less than 0.0015. Therefore, in sample 13,
Insufficient sintering resulted in a dielectric constant of 98, as shown in Table 4.
It is as low as 0 and the dielectric loss is as large as 13.1%.
The capacity temperature change rate exceeds ± 15%, the specific resistance is lower than 13.0 Ω · cm, and the average failure time is extremely short to the extent that it cannot be measured. A failure occurs at the moment when voltage is applied at high temperature. It was

On the other hand, similarly, in the sample 14 outside the scope of the present invention, as shown in Table 2, the SiO ₂ content δ is 0.085 which exceeds 0.08. Therefore, sample 1
In No. 4, as shown in Table 4, the capacity temperature change rate is ± 15%.
The average failure time was as short as 10 hours.

Further, in the sample 15 outside the scope of the present invention, as shown in Table 2, the Li ₂ O content ε was 0.001.
Is less than 0.0008. Therefore, in sample 15,
Insufficient sintering resulted in a dielectric constant of 10 as shown in Table 4.
It is as low as 20, the dielectric loss is large as 11.5%, the capacity temperature change rate exceeds ± 15%, and the specific resistance is 13.0.
It was lower than Ω · cm, and the mean time to failure was extremely short to the extent that it could not be measured.

On the other hand, similarly, in sample 16 outside the scope of the present invention, as shown in Table 2, the Li ₂ O content ε is 0.055, which is more than 0.055. Therefore, sample 1
6, the capacity temperature change rate is ± 15% as shown in Table 4.
The average failure time was 60 hours, which was relatively short.

For these, it is within the scope of the present invention.
In Samples 17 to 35, from Table 1 and Table 2 or Table 3,
Is clear. Ca modification amount x is 0.04 ≦ x ≦
The condition of 0.20 is satisfied. (Ba, Ca) / Ti
The ratio m satisfies the condition of 0.990 ≦ m. Also, this
Samples 17-35 within the scope of the invention of Table 2 or Table 2 or
The following is clear from Table 3. (Ba, Ca) / T
i ratio m and BaO content α₁And CaO content α₂Sum of,
That is, m + α₁+ Α₂Is 1.035 <m + α ₁+ Α₂
The relationship is ≦ 1.07. MnO content β is 0.000
The condition of 1 ≦ β ≦ 0.05 is satisfied. MgO content
γ satisfies the condition of 0.0001 ≦ γ ≦ 0.025
It SiO₂Content δ is 0.002 ≦ δ ≦ 0.08
Satisfies the matter. Furthermore, Li₂O content ε is 0.0
The condition of 01 ≦ ε ≦ 0.05 is satisfied.

Therefore, in these samples 17 to 35, as shown in Tables 4 and 5, the dielectric constant is 1500 or more, the dielectric loss is 3.0% or less, and the capacity temperature change rate is within ± 15%. , The capacitance electric field change rate is 10% or less in absolute value, the specific resistance is 13.0 Ω · cm or more, and the average failure time is 100 hours or more, which is excellent in reliability. It could be fired at a temperature of 1200 ° C. or lower.

Further, in Samples 17 to 35, when the dielectric ceramic portion after sintering was observed with a high resolution electron microscope, it was confirmed that there were no particles having a core-shell structure and the domain structure was formed up to the end. It was

While the present invention has been described with reference to a laminated ceramic capacitor, the dielectric ceramic composition according to the present invention is formed along a plurality of laminated dielectric ceramic layers and a specific interface between the dielectric ceramic layers. A laminated ceramic electronic component including a laminated body including the formed internal electrodes can be advantageously used as a material for the dielectric ceramic layer in a laminated ceramic electronic component other than the laminated ceramic capacitor.

[0091]

As described above, according to the dielectric ceramic composition of the present invention, the temperature characteristics of the dielectric constant of the sintered body obtained by firing the composition are good, and the static characteristics with respect to the DC voltage are high. A small change in capacitance and high reliability can be provided.

Further, the dielectric ceramic composition according to the present invention does not become a semiconductor even when fired in a reducing atmosphere,
Since a high specific resistance can be given, if a laminated ceramic electronic component such as a laminated ceramic capacitor is formed using a sintered body obtained by firing this, base metal is used as a conductive component contained in the internal electrodes. A certain nickel or nickel alloy can be used without any problems, and as a result, the cost of the monolithic ceramic electronic component can be reduced.

Further, according to the dielectric ceramic composition of the present invention, the temperature characteristics of the dielectric constant of the sintered body obtained by firing the composition are not flattened based on the core-shell structure, but rather the composition is not flat. Since the material is flattened based on the original temperature characteristics of the material, it is possible to reduce the variation in the temperature characteristics of the dielectric constant due to the firing temperature. Therefore, a monolithic ceramic electronic component such as a monolithic ceramic capacitor formed by using this dielectric ceramic composition can have small variations in characteristics, stable temperature characteristics of permittivity, and excellent characteristics.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing a monolithic ceramic capacitor 1 as an example of a monolithic ceramic electronic component formed by using a dielectric ceramic composition according to the present invention.

[Explanation of symbols]

1 Multilayer ceramic capacitors 2 laminate 3 Dielectric ceramic layer 4,5 internal electrodes 8,9 External electrode 10,11 Sintered layer 12, 13, 14, 15 Plating layer

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4G031 AA01 AA03 AA04 AA06 AA11                       AA19 AA30 BA09 CA08 GA01                       GA04 GA06 GA10 GA11                 5E001 AB03 AE02 AE03 AH01 AH05                       AH09 AJ01 AJ02                 5G303 AA01 AB11 AB20 BA12 CA01                       CB03 CB06 CB16 CB17 CB18                       CB30 CB35

Claims (6)

[Claims] 1. A general formula: (Ba _1-x Ca _x ) _m TiO ₃
+ Α ₁ BaO + α ₂ CaO + βMnO + γMgO + δS
A dielectric ceramic composition represented by iO ₂ + εLi ₂ O, wherein 0.04 ≦ x ≦ 0.20, 1.035 <m + α ₁ + α ₂ ≦ 1.07, 0.990 ≦ m, 0.0001 A dielectric ceramic composition satisfying the conditions of ≦ β ≦ 0.05, 0.0001 ≦ γ ≦ 0.025, 0.002 ≦ δ ≦ 0.08, and 0.001 ≦ ε ≦ 0.05. 2. A laminate, comprising: a plurality of laminated dielectric ceramic layers and internal electrodes formed along a specific interface between the dielectric ceramic layers, wherein the dielectric ceramic layer comprises: A laminated ceramic electronic component comprising the dielectric ceramic composition as described in 1. 3. The multilayer ceramic electronic component of claim 2, wherein the internal electrodes include nickel or a nickel alloy. 4. An outer electrode electrically connected to the inner electrode is formed on an outer surface of the laminate, and the outer electrode comprises a sintered layer containing a sintered body of conductive metal powder. The multilayer ceramic electronic component according to claim 2 or 3, which is provided. 5. The monolithic ceramic electronic component according to claim 4, wherein the external electrode includes at least one plating layer formed on the sintered layer. 6. A plurality of the internal electrodes are formed to face each other via the dielectric ceramic layer so as to form a capacitance, and are electrically connected to a specific one of the internal electrodes. The multilayer ceramic electronic component according to claim 4, wherein the external electrode is formed as described above to form a multilayer ceramic capacitor.