JP3340723B2 - Method for producing dielectric porcelain composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
0 or more, and the capacity temperature characteristic satisfies the X8R characteristic (−55 to 150 ° C., ΔC = ± 15%) of the EIA standard,
Low dielectric loss, high dielectric constant and insulation resistance,
The present invention relates to a method for producing a reduction-resistant dielectric ceramic composition having excellent high-temperature accelerated life characteristics.

[0002]

2. Description of the Related Art Multilayer ceramic capacitors are widely used as small, large-capacity, highly reliable electronic components.
The number used in one electronic device is also large.
In recent years, with the miniaturization and high performance of devices, demands for further miniaturization, large capacity, low price, and high reliability of multilayer ceramic capacitors have become more and more severe.

As a dielectric ceramic composition having a high dielectric constant and a flat capacitance-temperature characteristic, BaTiO ₃ is mainly used, and Nb ₂ O ₅ —Co ₃ O ₄ , Mg
OY, rare earth elements (Dy, Ho, etc.), Bi ₂ O ₃
Composition with the addition of such -TiO ₂ are known. The temperature characteristic of the dielectric ceramic composition containing BaTiO ₃ as a main component is such that the Curie temperature of BaTiO ₃ is about 1
Since it is around 20, it is very difficult to satisfy the R characteristic (ΔC = ± 15%) of the capacitance temperature characteristic in a high temperature region of 130 ° C. or more. For this reason, the BaTiO ₃ based high dielectric constant material has the EIA standard X7R characteristic (−55 to 125 ° C., Δ
C = within ± 15%).

In recent years, multilayer ceramic capacitors have been used in various electronic devices such as an engine electronic control unit (ECU), a crank angle sensor, and an antilock brake system (ABS) module mounted in an engine room of an automobile. ing. Since these electronic devices are for stably performing engine control, drive control, and brake control, they are required to have good circuit temperature stability.

In an environment where these electronic devices are used, it is expected that the temperature drops to about -20 ° C. or less in winter in a cold region, and that the temperature rises to about + 130 ° C. or more in summer after the engine is started. Is done. Recently, there has been a tendency to reduce the number of wire harnesses connecting electronic devices and their controlled devices, and the electronic devices are sometimes installed outside the vehicle, so the environment for the electronic devices is becoming increasingly severe. Therefore, the conventional dielectric ceramic composition having the X7R characteristic cannot cope with these uses.

[0006] Further, as a temperature compensating capacitor material having excellent temperature characteristics, (Sr, Ca) (Ti, Zr) O
₃ system, Ca (Ti, Zr) O ₃ system, Nd ₂ O ₃
-2TiO ₂ -based, La ₂ O ₃ -2TiO ₂ -based and the like are generally known, but since these compositions have a very low relative dielectric constant (generally 100 or less), it is necessary to produce a capacitor having a large capacity. Is virtually impossible.

On the other hand, in order to satisfy X8R characteristics in a dielectric ceramic composition containing BaTiO ₃ as a main component,
It has been proposed to shift the Curie temperature to a higher temperature side by replacing Ba in BaTiO ₃ with Bi, Pb or the like (Japanese Patent Application Laid-Open Nos. 10-25157, 9).
-40465 publication). Also, BaTiO ₃ + CaZ
It has also been proposed to satisfy the X8R characteristic by selecting a composition of rO ₃ + ZnO + Nb ₂ O ₅ (JP-A-4-295048 and JP-A-4-29245).
No. 8, No. 4-292559, No. 5-1093
19, 6-243721). However, in any of these composition systems, P
Since b, Bi, and Zn are used, firing in an oxidizing atmosphere such as in air is a prerequisite. Therefore, inexpensive base metals such as Ni cannot be used for the internal electrodes of the capacitor,
There is a problem that expensive precious metals such as Pd, Au, and Ag must be used.

[0008]

In order to solve such a problem, the present applicant has proposed a dielectric porcelain composition in which Ni or a Ni alloy can be used as an internal electrode of a capacitor. Japanese Patent Application No. 10-2206, Japanese Patent Application No. 11-206291, Japanese Patent Application No. 11-2062
No. 92).

According to these techniques, Sc, Er, T
By including rare earth elements such as m, Yb, and Lu in the dielectric porcelain composition, the Curie temperature shifts to a higher temperature side, the rate of capacitance temperature change above the Curie temperature is flattened, and the reliability (high temperature load) increases. Life span, change in capacity posting, etc.)
Can be improved.

[0010] However, when the amount of the rare earth added to the dielectric ceramic composition is increased, the second phase mainly composed of the rare earth tends to precipitate in the dielectric. The precipitation of the second phase improves the strength of the dielectric. However, depending on the thickness of the dielectric layer, the deposited second phase becomes substantially equal to the thickness of the dielectric layer of the multilayer capacitor, and the It has been confirmed by the present inventors that the reliability may be degraded. Further, as the amount of the second phase precipitated in the dielectric layer increases, the product of the dielectric constant and the insulation resistance (CR
The present inventors have also confirmed that the product tends to decrease.

[0011] In addition, the multilayer ceramic capacitors mounted on automobiles have been increasing in capacity and miniaturization, and the thickness of the dielectric layer has tended to be further reduced. For this reason,
In particular, in the case of a dielectric porcelain composition in which a rare earth is added to the dielectric porcelain composition, a technique for controlling the size and amount of the deposited second phase is required.

By the way, in order to improve the reliability of the dielectric ceramic composition having the X7R characteristic, BaTiO as a main raw material is used.
No. ₃ and an additive are calcined in advance (Japanese Patent Publication No. Hei 7-118431). In the technique disclosed in this publication, the composition of a dielectric material finally synthesized is (Ba,
Mg, Ca, Sr, Zn) (Ti, R) O ₃ + (C
a, Ba) ZrO ₃ + glass. Then, R = Sc, Y, Gd, Dy, Ho, Er, Yb, T
b, Tm, Lu, (Ba + Mg + Ca + Sr
+ Zn) / (Ti + Zr + R).
BaTiO ₃ and additives are calcined so as to be in the range of 00 to 1.04.

However, according to this method, the alkaline earth (Mg, Ca, Sr, Ba) dissolves in the Ba site, and the rare earth (R = Sc, Y, Gd, Dy, Ho, E, E).
(r, Yb, Tb, Tm, Lu) are premised on forming a solid solution at the Ti site. Therefore, it is necessary to increase the amount of the alkaline earth added with the increase in the amount of the rare earth added. When the molar ratio is specified in this composition system, the high-temperature load life (IR life), which is the X8R characteristic, is deteriorated. In addition, when the amount of alkaline earth is increased, problems such as deterioration of sinterability occur. In addition, there is a problem that Zn easily evaporates.

An object of the present invention is to provide Ni and N for internal electrodes.
It can be suitably used as a dielectric porcelain composition for a multilayer chip capacitor in which a base metal such as an i-alloy can be used. An object of the present invention is to provide a method capable of manufacturing a dielectric ceramic composition having a small dielectric loss, a high dielectric constant and an insulation resistance, and an excellent high-temperature accelerated life characteristic while satisfying the X8R temperature characteristic. .

[0015]

In order to achieve the above object, a method for producing a dielectric ceramic composition according to the present invention comprises a main component comprising barium titanate and a second subcomponent which is a sintering aid. And a method for producing a dielectric ceramic composition having at least a sixth sub-component containing CaZrO ₃ or CaO + ZrO ₂ , and other sub-components, except for the second sub-component, with respect to the main component. Preparing a powder before calcining by mixing at least a part of the sixth sub-component and other sub-components; and calcining the powder before calcining to obtain a calcined powder. And a step of mixing at least the second subcomponent with the calcined powder to obtain a dielectric ceramic composition in which the ratio of each subcomponent to the main component is a predetermined molar ratio. Have.

In the present invention, titanium as the main component is used.
Barium acid has a composition formula of Ba_mTiO_{2 + m}Represented by
M in the above composition formula is 0.995 ≦ m ≦ 1.010
And the ratio of Ba to Ti is 0.995 ≦ Ba / Ti ≦
1.010, wherein the second subcomponent is SiO 2₂The lord
MO (where M is Ba, Ca, Sr and
And at least one element selected from Mg), Li₂
O and B ₂O₃At least one selected from
Preferably.

In the present invention, more preferably,
The second subcomponent is (Ba, Ca) _xSiO_{2 + x}
(Where x = 0.7 to 1.2)
You. The second subcomponent is considered to function as a sintering aid.
You. The second subcomponent is (Ba, Ca)_xSiO
_{2 + x}(Where x = 0.7 to 1.2)
In the case where the second subcomponent has Ba,
And the ratio of Ca to Ca is arbitrary and contains only one
But it is good.

According to a first aspect of the present invention, the other subcomponent is MgO, CaO, BaO, SrO and Cr.
A first subcomponent including at least one selected from ₂ O _3, a third subcomponent including at least one kind selected from V ₂ O 5, MoO ₃ and WO _3, an oxide of R1 (where R1 at least one selected from Sc, Er, Tm, Yb and Lu), and at least the second subcomponent is mixed with the calcined powder; The ratio of each subcomponent to 100 mol of the main component is as follows: the first subcomponent: 0.1 to 3 mol, the second subcomponent: 2 to 10 mol, the third subcomponent: 0.01 to 0.5 mol, Four subcomponents: 0.5 to 7 mol (however, the number of moles of the fourth subcomponent is a ratio of R1 alone), and sixth subcomponent: 0 to 5 mol (however, 0 is not included). It is preferable to obtain a dielectric porcelain composition.

According to a second aspect of the present invention, the other subcomponent is MgO, CaO, BaO, SrO and Cr.
A first subcomponent including at least one selected from ₂ O _3, a third subcomponent including at least one kind selected from V ₂ O 5, MoO ₃ and WO _3, an oxide of R1 (where R1 is a fourth subcomponent containing at least one selected from Sc, Er, Tm, Yb and Lu, and an oxide of R2 (where R2 is Y, Dy, Ho, T
b, at least one selected from Gd and Eu), and at least the second subcomponent is mixed with the calcined powder, and the main component 1
The ratio of each subcomponent with respect to 00 mol is as follows: first subcomponent: 0.1 to 3 mol, second subcomponent: 2 to 10 mol, third subcomponent: 0.01 to 0.5 mol, fourth subcomponent : 0.5 to 7 moles (where the number of moles of the fourth subcomponent is a ratio of R1 alone), the fifth subcomponent: 2 to 9 moles (however, the number of moles of the fifth subcomponent is R2 It is preferable to obtain a dielectric ceramic composition in which the sixth subcomponent is 0 to 5 mol (however, 0 is not included).

According to a first aspect of the present invention, the molar ratio of components contained in the powder before calcination: (Ba + Ca + metal element in first subcomponent) / (Ti + Zr + R1) is less than 1 or (Ba + Ca + R1). It is preferable that the powder before calcining is prepared and calcined so that / (Ti + Zr + metal element in the first subcomponent) exceeds 1.

According to a second aspect of the present invention, the molar ratio of the components contained in the powder before calcination: (Ba + Ca + metal element in the first subcomponent) / (Ti + Zr + R1 + R2) is less than 1 or (Ba + Ca + R1 + R2). / (Ti + Zr
It is preferable that the powder before calcining is prepared and calcined so that (+ the metal element in the first subcomponent) exceeds 1.

According to a second aspect of the present invention, when preparing the powder before calcination, it is preferable that the powder before calcination always contains the fifth subcomponent. Further, when preparing the powder before calcining, it is preferable that the powder before calcining always includes the first subcomponent. Furthermore, when preparing the powder before calcination,
It is more preferable that the powder before calcining always contains the first subcomponent, the fourth subcomponent, and the fifth subcomponent. Furthermore, the number of moles of the first subcomponent contained in the powder before calcining is the total number of moles of the fourth and fifth subcomponents (however, the number of moles of the fourth and fifth subcomponents). Is the ratio of R1 alone and R2 alone, respectively).

In the present invention, the powder before calcination is preferably used at a temperature of 700 to 1100 ° C., more preferably 800 ° C.
It is calcined at a temperature of 〜１０1050 ° C. Note that the calcination may be performed a plurality of times.

The calcined powder may be mixed with at least the second subcomponent. If necessary, the main component, the first subcomponent, the third subcomponent, the fourth subcomponent, and the fifth subcomponent may be mixed. One or more of the sub-component and the sixth sub-component may be further mixed as long as the composition of the dielectric ceramic composition finally obtained falls within the above range.

[0025]

According to the conventional method for producing a dielectric ceramic composition, barium titanate and an additive are mixed at once to prepare a mixed powder of the dielectric ceramic composition or a dielectric paste. However, according to this method, segregation of additives (first to sixth subcomponents) and the like occurs in the dielectric ceramic composition after firing, and the composition of each crystal varies. Such segregation deteriorates the dielectric constant and insulation resistance of the dielectric.

According to the present invention, except for the second sub-component, the main component and at least one of the first sub-component, the third sub-component, the fourth sub-component, the fifth sub-component and the sixth sub-component. And calcining the mixture to suppress the composition variation between the crystal grains, thereby suppressing the segregation of the segregated phase, controlling the size of the segregated phase, and satisfying the X8R characteristics while maintaining insulation. It is possible to manufacture a dielectric ceramic composition having improved reliability and relative permittivity and having excellent reliability. This was first discovered by the present inventors.

According to the present invention, two or more rare earth elements (fourth and fifth subcomponents) are contained in the dielectric porcelain composition.
In addition to the above, when the fifth subcomponent is always contained in the powder before calcination, the precipitation of the segregated phase is suppressed, the size of the segregated phase is controlled, and the CR is obtained while satisfying the X8R characteristic. The product and reliability can be improved, and a dielectric ceramic composition having excellent reliability can be manufactured. This was also found for the first time by the present inventors.

Further, according to the present invention, the effect of shifting the Curie temperature to the higher temperature side and the effect of flattening the capacitance temperature characteristic are obtained by including the sixth subcomponent in the dielectric ceramic composition. is there. It also has the effect of improving the CR product and the DC breakdown strength.

Since the capacitor manufactured by the method according to the present invention can satisfy X8R of the EIA standard, it can be used in an environment exposed to a high temperature such as an engine room of an automobile. In addition, the dielectric ceramic composition obtained by the manufacturing method according to the present invention does not contain elements such as Pb, Bi, and Zn which are evaporated and scattered, and therefore can be fired even in a reducing atmosphere. For this reason, it is possible to use a base metal such as Ni and a Ni alloy as the internal electrode, and it is possible to reduce the cost.

Further, the dielectric ceramic composition obtained by the production method according to the present invention can be used even when fired in a reducing atmosphere.
It satisfies the X8R characteristic, has little deterioration in the capacity aging characteristic and insulation resistance due to the application of a DC electric field, and has excellent reliability. For this reason, an effect can be expected as a method of suppressing the deterioration of the temperature change rate in the high temperature region due to the thinning of the multilayer capacitor.

Further, the dielectric porcelain composition obtained by the production method according to the present invention does not contain substances such as Pb, Bi and the like, so that a product having little adverse effect on the environment due to disposal and disposal after use is provided. it can.

Further, according to the production method of the present invention, a dielectric ceramic composition having a uniform structure with a small amount of heterophase formed by precipitation of an additive can be realized, and the dielectric constant of the dielectric ceramic composition can be improved. Insulation resistance can be improved. Further, the manufacturing method according to the present invention can provide a multilayer ceramic capacitor having high reliability, since it is possible to prevent a structural defect from occurring accidentally.

Further, since the hetero-phase precipitation can be suppressed without changing the additive composition, a dielectric ceramic composition having a capacity-temperature characteristic satisfying the X8R characteristic can be easily manufactured.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments shown in the drawings. FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor, FIG. 2 is a graph showing a preferable relationship between a fourth sub-component and a sixth sub-component in the dielectric ceramic composition according to one embodiment of the present invention, and FIG. And FIG. 4 is a graph showing the relationship between the content of the sixth subcomponent and the CR product, and FIG. 5 is obtained by a reference example of the present invention. FIG. 6 is a graph showing the capacitance temperature characteristics of the obtained dielectric ceramic composition, and FIG. 6 is a graph showing the capacitance temperature characteristics and the bias characteristics of the dielectric ceramic composition obtained according to the example of the present invention.

Multilayer Ceramic Capacitor Before describing the method for producing the dielectric ceramic composition according to the present invention, the multilayer ceramic capacitor will be described first. As shown in FIG. 1, a multilayer ceramic capacitor 1 according to one embodiment of the present invention has a capacitor element body 1 having a configuration in which dielectric layers 2 and internal electrode layers 3 are alternately stacked.
Has zero. At both ends of the capacitor element body 10, a pair of external electrodes 4 are formed which are electrically connected to the internal electrode layers 3 alternately arranged inside the element body 10. The shape of the capacitor element body 10 is not particularly limited, but is generally a rectangular parallelepiped. The dimensions are not particularly limited, and may be appropriately determined according to the application.
(0.6-5.6mm) x (0.3-5.0mm) x
(0.3 to 1.9 mm).

The internal electrode layers 3 are laminated so that each end face is alternately exposed on the surface of the two opposing ends of the capacitor element body 10. The pair of external electrodes 4 are formed at both ends of the capacitor element body 10 and connected to the exposed end faces of the alternately arranged internal electrode layers 3 to form a capacitor circuit.

[0037] Dielectric Layer 2 The dielectric layer 2 includes a dielectric ceramic composition obtained by the production method according to an embodiment of the present invention. The dielectric ceramic composition obtained by the manufacturing method according to one embodiment of the present invention includes a main component containing barium titanate, MgO, Ca
A first subcomponent containing at least one selected from O, BaO, SrO and Cr ₂ O ₃ , and SiO ₂ as a main component, and MO (where M is at least one selected from Ba, Ca, Sr and Mg) One element), Li ₂
A second subcomponent containing at least one selected from O and B ₂ O ₃ , V ₂ O ₅ , MoO ₃ and WO
_{A third} subcomponent containing at least one selected from the group consisting of R.3 and an oxide of R1 (where R1 is Sc, Er, Tm,
A fourth subcomponent containing at least one selected from Yb and Lu), and CaZrO ₃ or CaO + ZrO.
_{And a} sixth ceramic component containing at least a _second subcomponent.

The ratio of each of the above-mentioned sub-components to barium titanate, which is the main component, is as follows: 100 mol of barium titanate; 0.1 to 3 mol of the first sub-component; 2 to 10 mol of the second sub-component; 3 subcomponents: 0.01 to 0.5 mol, 4th subcomponent: 0.5 to 7 mol, 6th subcomponent: 0 to 5 mol (however, 0 is not included). Sub-component: 0.5 to 2.5 mol, Second sub-component: 2.0 to 5.0 mol, Third sub-component: 0.1 to 0.4 mol, Fourth sub-component: 0.5 to 5 0.0 mol, Sixth subcomponent: 0.5 to 3 mol.

The above ratio of the fourth subcomponent is not the molar ratio of R1 oxide but the molar ratio of R1 alone. That is, for example, when an oxide of Yb is used as the fourth subcomponent, the fact that the ratio of the fourth subcomponent is 1 mol means that Yb ₂
The ratio of O ₃ Instead of 1 mole, the ratio of Yb is meant to be 1 mol.

In the present specification, each oxide constituting the main component and each subcomponent is represented by a stoichiometric composition. However, the oxidation state of each oxide may deviate from the stoichiometric composition. Good. However, the above ratio of each subcomponent is determined by converting the amount of metal contained in the oxide constituting each subcomponent to an oxide having the above stoichiometric composition. In addition, as the raw material powder of the dielectric ceramic composition, the above-described oxides and mixtures thereof, and composite oxides can be used.In addition, various compounds that become the above-described oxides and composite oxides by firing, for example,
Carbonates, oxalates, nitrates, hydroxides, organometallic compounds and the like can be appropriately selected and used as a mixture.

The reasons for limiting the contents of the above subcomponents are as follows. The first subcomponent (MgO, CaO, BaO,
If the contents of SrO and Cr ₂ O ₃ ) are too small, the rate of change in capacity with temperature will increase. On the other hand, if the content is too large, the sinterability tends to deteriorate and the IR life tends to deteriorate. Note that the constituent ratio of each oxide in the first subcomponent is arbitrary.

If the content of the second subcomponent is too small, the capacity-temperature characteristics deteriorate and the IR (insulation resistance) decreases. On the other hand, if the content is too large, the IR life becomes insufficient and the dielectric constant sharply decreases. The second subcomponent mainly acts as a sintering aid, but also has the effect of improving the defect rate of the initial insulation resistance when the dielectric layer is thinned. Preferably, the second subcomponent is (Ba, C
a) _x SiO _{2 + x} (where x = 0.7 to 1.x)
2). BaO and CaO in _{[(Ba, Ca) x SiO} 2 + x] as a more preferable embodiment of the second subcomponent are also included in the first subcomponent, a composite oxide _{(Ba, Ca) x SiO 2} + x is In the present invention, it is preferable to add BaO and / or CaO as the above-mentioned composite oxide, because the melting point is low and the reactivity with the main component is good. _{X in} (Ba, Ca) xSiO2 _{+ x} as a more preferred embodiment of the _second subcomponent is preferably 0.7 to 1.2, and more preferably 0.8 to 1.1. If x is too small, that is, if there is too much SiO ₂ , the main component BaTiO
₃ and deteriorates the dielectric properties. on the other hand,
If x is too large, the melting point becomes high and the sinterability deteriorates, which is not preferable. The ratio between Ba and Ca is arbitrary, and may contain only one of them. Third subcomponent (V ₂ O ₅ , MoO ₃ and WO ₃ )
Shows the effect of flattening the capacitance-temperature characteristic at the Curie temperature or higher and the effect of improving the IR lifetime. If the content of the third subcomponent is too small, such an effect becomes insufficient. On the other hand, when the content is too large, the IR is significantly reduced. Note that the constituent ratio of each oxide in the third subcomponent is arbitrary.

The fourth subcomponent (R1 oxide) exhibits an effect of shifting the Curie temperature to a higher temperature side and an effect of flattening the capacitance-temperature characteristic. If the content of the fourth subcomponent is too small, such an effect becomes insufficient, and the capacity-temperature characteristics deteriorate. On the other hand, if the content is too large, the sinterability tends to deteriorate. Among the fourth subcomponents, a Yb oxide is preferable because it has a high property improving effect and is inexpensive.

In the dielectric ceramic composition of the present invention, if necessary, R2 oxide (where R2 is at least one selected from Y, Dy, Ho, Tb, Gd and Eu) may be used as a fifth subcomponent. Is preferably contained. The fifth subcomponent (R2 oxide) has an effect of improving IR and IR life, and has little adverse effect on the capacity-temperature characteristics. However, when the content of the R2 oxide is too large, the sinterability tends to deteriorate. Among the fifth subcomponents, a Y oxide is preferable because it has a high property improving effect and is inexpensive.

The total content of the fourth subcomponent and the fifth subcomponent is preferably 13 mol or less, more preferably 10 mol or less with respect to 100 mol of BaTiO _{3 as} the main component (however, the fourth subcomponent and the The number of moles of the fifth subcomponent is R
1 and R2 alone). This is for maintaining good sinterability.

In the dielectric ceramic composition of the present invention, CaZrO ₃ or CaO + ZrO is used as the sixth subcomponent.
₂ is included. In the sixth subcomponent, Ca and Zr
The molar ratio with is arbitrary, but preferably Ca / Zr =
0.5-1.5, more preferably Ca / Zr = 0.8-
1.5, particularly preferably Ca / Zr = 0.9 to 1.1.

In this case, preferably, the number of moles of the fourth subcomponent and the sixth subcomponent with respect to 100 moles of barium titanate as the main component (however, the number of moles of the fourth subcomponent is a ratio of R1 alone) Is represented by the X coordinate and the Y coordinate, respectively, the mole numbers of the fourth subcomponent and the sixth subcomponent are Y = 5, Y = 0, and Y = (2/3) X− (7
/ 3), within the range surrounded by the straight lines of X = 0.5 and X = 5 (but not on the boundary line of Y = 0) (area a in FIG. 2; other than Y = 0) Including on the border).

More preferably, the number of moles of the fourth subcomponent and the sixth subcomponent with respect to 100 moles of barium titanate as the main component (however, the number of moles of the fourth subcomponent is a ratio of R1 alone) , When represented by the X coordinate and the Y coordinate, respectively, the number of moles of the fourth subcomponent and the sixth subcomponent is
Y = 5, Y = 0, Y = (2/3) X− (7/3), Y =
-(1.5) X + 9.5, X = 1 and X = 5 are within the range (but not on the boundary of Y = 0) (area b in FIG. 2, Y = 0).

The sixth subcomponent (CaZrO ₃ or CaO
+ ZrO ₂ ) has an effect of shifting the Curie temperature to a higher temperature side and an effect of flattening the capacitance-temperature characteristic. It also has the effect of improving the CR product and the DC breakdown strength.
However, when the content of the sixth subcomponent is too large, the IR accelerated life is significantly deteriorated, and the capacity-temperature characteristic (X8R characteristic) is deteriorated. Therefore, the content of the sixth subcomponent is B
0 to 5 mol (but not including 0), preferably 0.5 to 5 mol, per 100 mol of aTiO _3.
3 moles.

The addition form of CaZrO ₃ is not particularly limited, and an oxide composed of Ca such as CaO, CaCO
_{3 and the} like, organic compounds, CaZrO _{3 and the} like.

By adjusting the contents of the fourth subcomponent (R1 oxide) and the sixth subcomponent (CaZrO ₃ etc.),
Capacitance-temperature characteristics (X8R characteristics) can be flattened, and high-temperature accelerated life and CR product can be improved. In particular, within the above-mentioned numerical range, the precipitation of a different phase is suppressed, and the structure can be made uniform. If the content of the fourth subcomponent and / or the fifth subcomponent is too large, the pyrochlore phase, which is a needle-like crystal, is likely to precipitate, and when the thickness between the dielectric layers of the multilayer ceramic capacitor is reduced, the characteristics deteriorate significantly ( (Reduction of CR product). On the other hand, if the content of the fourth subcomponent and / or the fifth subcomponent is too small, the capacity-temperature characteristics tend not to be satisfied.

Further, the dielectric ceramic composition of the present invention may contain MnO as a seventh subcomponent. The seventh subcomponent has the effect of promoting sintering, the effect of increasing IR, and the effect of improving IR life. In order to sufficiently obtain such an effect, the ratio of the seventh subcomponent to 100 mol of barium titanate is preferably 0.01 mol or more. However, if the content of the seventh subcomponent is too large, the capacity-temperature characteristics are adversely affected, so the content is preferably 0.5 mol or less.

In the dielectric porcelain composition of the present invention,
In addition to the above oxides, Al₂O₃ May be included
No. Al₂O₃Has a large effect on the capacitance-temperature characteristics
Not to improve sinterability, IR and IR life
You. Where Al₂O₃Too high content of sintering
Deteriorates and the IR decreases, so that Al₂O₃Is good
Preferably, BaTiO₃1 mol or less per 100 mol
Below, more preferably, 1 mole of the entire dielectric porcelain composition.
It is as follows.

At least one of Sr, Zr and Sn is composed of Ba in the main component of the perovskite structure.
Alternatively, when Ti is substituted, the Curie temperature shifts to a lower temperature side, so that the capacity-temperature characteristics at 125 ° C. or higher deteriorate. Therefore, BaTiO ₃ containing these elements is used.
It is preferable not to use [for example, (Ba, Sr) TiO ₃ ] as a main component. However, there is no particular problem as long as it is contained as an impurity (about 0.1 mol% or less of the whole dielectric ceramic composition).

The average crystal grain size of the dielectric ceramic composition of the present invention is not particularly limited, and may be appropriately determined, for example, within a range of 0.1 to 3.0 μm according to the thickness of the dielectric layer.
The capacitance-temperature characteristics tend to be worse as the dielectric layer is thinner, and worse as the average crystal grain size is smaller. For this reason, the dielectric ceramic composition of the present invention is particularly effective when the average crystal grain size needs to be reduced, specifically, when the average crystal grain size is 0.1 to 0.5 μm. is there. In addition, if the average crystal grain size is reduced, the IR life is prolonged, and the change with time in the capacity under a DC electric field is reduced, and from this point, the average crystal grain size is preferably small as described above. .

The Curie temperature (the phase transition temperature from ferroelectric to paraelectric) of the dielectric porcelain composition of the present invention can be changed by selecting the composition, but in order to satisfy the X8R characteristic. Is preferably 120 ° C. or higher, more preferably 123 ° C. or higher. The Curie temperature is
It can be measured by DSC (differential scanning calorimetry) or the like.

The thickness of the dielectric layer composed of the dielectric ceramic composition of the present invention is usually 40 μm or less per layer,
In particular, it is 30 μm or less. The lower limit of the thickness is usually 2 μm
It is about. The dielectric ceramic composition of the present invention is effective for improving the capacitance-temperature characteristics of a multilayer ceramic capacitor having such a thin dielectric layer. The number of stacked dielectric layers is usually about 2 to 300.

The multilayer ceramic capacitor using the dielectric ceramic composition of the present invention has a temperature of 80.degree.
It is suitable for use as an electronic component for equipment used in an environment of 0 ° C. In such a temperature range, the temperature characteristic of the capacitance satisfies the R characteristic of the EIA standard.
The X8R characteristics are also satisfied. In addition, the EIAJ standard B characteristic [capacity change rate within ± 10% at −25 to 85 ° C. (reference temperature 20 ° C.)] and the EIA standard X7R characteristic (−55 to 125
° C, ΔC = within ± 15%) at the same time.

In the case of a multilayer ceramic capacitor, the dielectric layer usually has a thickness of 0.02 V / μm or more, especially 0.2 V / μm.
Above, more than 0.5V / μm, generally 5V / μm
An AC electric field of less than about and a DC electric field of 5 V / μm or less are superimposed on the AC electric field. Even when such an electric field is applied, the temperature characteristics of the capacitance are extremely stable.

[0060] Without being limited internal electrode layers 3 A conductive material included in the internal electrode layer 3 in particular, since the material constituting the dielectric layer 2 has reduction resistance, a base metal can be used. As the base metal used as the conductive material, Ni or a Ni alloy is preferable. The Ni alloy is selected from Mn, Cr, Co and Al.
An alloy of at least one kind of element and Ni is preferable.
The content is preferably at least 95% by weight. In addition,
Various trace components such as P are contained in Ni or Ni alloy in an amount of 0.1%.
It may be contained up to about 1% by weight. The thickness of the internal electrode layer may be appropriately determined according to the application and the like.
It is preferably about 5 to 5 μm, particularly about 0.5 to 2.5 μm.

External electrode 4 The conductive material contained in the external electrode 4 is not particularly limited.
In the present invention, inexpensive Ni, Cu and their alloys can be used. The thickness of the external electrode may be appropriately determined according to the use or the like, but is usually preferably about 10 to 50 μm.

Manufacturing Method of Multilayer Ceramic Capacitor A multilayer ceramic capacitor manufactured by using the manufacturing method of the dielectric ceramic composition according to the present invention is manufactured by forming a green chip by a normal printing method or a sheet method using a paste. After baking this, the external electrode is manufactured by printing or transferring and baking. Hereinafter, the manufacturing method will be specifically described.

First, a dielectric ceramic composition powder contained in the dielectric layer paste is prepared. In the present invention, calcination is performed before obtaining the dielectric ceramic composition powder having the above-described composition.
That is, as shown in FIG. 3, except for the second subcomponent (for example, (Ba, Ca) _x SiO _{2+ x} ), the main component (for example, BaTiO ₃ ), the first subcomponent (for example, MgCO ₃ ), and the third Secondary components (eg, V
₂ O ₅ ), the fourth subcomponent (for example, Yb
₂ O _3), fifth and mixing at least one of the sub-component (e.g. _Y 2 _{O 3)} and the sixth subcomponent (e.g. CaZrO _3), and dried to prepare a pre-calcination powder.

This pre-calcined powder is then calcined. The calcination conditions are not particularly limited, but are preferably performed under the following conditions. Heating rate: 50 to 400 ° C / hour, especially 100 to 300
° C / hour, holding temperature: 700 ° C to 1100 ° C, especially 700 ° C to 90 °
0 ° C., temperature holding time: 0.5 to 6 hours, particularly 1 to 3 hours Atmosphere: in air and nitrogen.

The calcined calcined powder is roughly pulverized by an alumina roll or the like, and then, as shown in FIG. 3, at least a second subcomponent (for example, (Ba, Ca) _x SiO 2).
_{2 + x} ), and optionally,
The remaining additives are added to the final composition described above. Thereafter, the mixed powder is mixed by a ball mill or the like, if necessary, and dried to obtain a dielectric ceramic composition powder having the composition of the present invention.

Next, this dielectric ceramic composition powder is made into a paint to prepare a dielectric layer paste. The dielectric layer paste may be an organic paint obtained by kneading a dielectric ceramic composition powder and an organic vehicle, or may be an aqueous paint.

As the dielectric ceramic composition powder, the above-mentioned oxides, mixtures thereof, and composite oxides can be used. In addition, various compounds that become the above-mentioned oxides and composite oxides by firing, for example, carbon dioxide Salts, oxalates, nitrates, hydroxides, organometallic compounds and the like can be appropriately selected and mixed for use. The content of each compound in the dielectric porcelain composition powder may be determined so as to have the above-described composition of the dielectric porcelain composition after firing. The particle size of the dielectric porcelain composition powder before coating is usually about 0.1 to 3 μm in average particle size.

The organic vehicle is obtained by dissolving a binder in an organic solvent. The binder used for the organic vehicle is not particularly limited, and may be appropriately selected from various ordinary binders such as ethyl cellulose and polyvinyl butyral. In addition, the organic solvent to be used is not particularly limited, and may be appropriately selected from various organic solvents such as terpineol, butyl carbitol, acetone, and toluene according to a method to be used such as a printing method and a sheet method.

In the case where the dielectric layer paste is an aqueous paint, an aqueous vehicle in which a water-soluble binder or dispersant is dissolved in water may be kneaded with a dielectric material. The water-soluble binder used for the aqueous vehicle is not particularly limited, and for example, polyvinyl alcohol, cellulose, a water-soluble acrylic resin, or the like may be used.

The paste for the internal electrode layer comprises a conductive material comprising the above-mentioned various dielectric metals or alloys, or various oxides, organometallic compounds, resinates, etc. which become the above-mentioned conductive material after firing, and the above-mentioned organic vehicle. It is prepared by kneading. The external electrode paste may be prepared in the same manner as the internal electrode layer paste described above.

The content of the organic vehicle in each of the above pastes is not particularly limited, and may be a usual content, for example, about 1 to 5% by weight of a binder and about 10 to 50% by weight of a solvent. Further, each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators, and the like, as necessary. Their total content is 1
The content is preferably 0% by weight or less.

When a printing method is used, the dielectric layer paste and the internal electrode layer paste are laminated and printed on a substrate such as PET, cut into a predetermined shape, and then separated from the substrate to form a green chip.

When the sheet method is used, a green sheet is formed by using a dielectric layer paste, an internal electrode layer paste is printed thereon, and these are laminated to form a green chip.

Before firing, the green chip is subjected to a binder removal treatment. The binder removal treatment may be performed under ordinary conditions. However, when a base metal such as Ni or a Ni alloy is used as the conductive material of the internal electrode layer, it is particularly preferable to perform the treatment under the following conditions. Heating rate: 5 to 300 ° C / hour, especially 10 to 100 ° C / hour
Time, holding temperature: 180 to 400 ° C, especially 200 to 300 ° C, Temperature holding time: 0.5 to 24 hours, especially 5 to 20 hours, Atmosphere: in air.

The atmosphere at the time of firing the green chip may be appropriately determined according to the type of the conductive material in the internal electrode layer paste, but when a base metal such as Ni or a Ni alloy is used as the conductive material, the firing atmosphere may be changed. Oxygen partial pressure is 10 ⁻⁸ to 1
Preferably, the pressure is ^0-12 atm. If the oxygen partial pressure is less than the above range, the conductive material of the internal electrode layer may abnormally sinter and be interrupted. If the oxygen partial pressure exceeds the above range, the internal electrode layer tends to be oxidized.

The holding temperature at the time of firing is preferably 1
100-1400 ° C, more preferably 1200-136
0 ° C, more preferably 1200-1340 ° C.
If the holding temperature is less than the above range, the densification becomes insufficient, and if the holding temperature exceeds the above range, the electrode is interrupted due to abnormal sintering of the internal electrode layer, the deterioration of the capacitance temperature characteristic due to the diffusion of the internal electrode layer constituent material, the dielectric Reduction of the body porcelain composition is likely to occur.

Various conditions other than the above conditions are preferably selected from the following ranges. Heating rate: 50 to 500 ° C / hour, especially 200 to 300
° C / hour, temperature holding time: 0.5-8 hours, especially 1-3 hours, cooling rate: 50-500 ° C / hour, especially 200-300
° C / hour. Note that the firing atmosphere is preferably a reducing atmosphere. As the atmosphere gas, for example, a mixed gas of N ₂ and H ₂ is preferably used after being humidified.

When firing in a reducing atmosphere, the capacitor element body is preferably annealed. Annealing is a process for re-oxidizing the dielectric layer, which can significantly increase the IR life, thereby improving reliability.

The oxygen partial pressure in the annealing atmosphere is 10 ⁻⁹
Atmospheric pressure or higher, preferably 10 ⁻⁶ atmospheric pressure or higher, especially 10 ⁻⁵
The pressure is preferably set to 10 to 10 ^-4 atm. When the oxygen partial pressure is less than the above range, it is difficult to reoxidize the dielectric layer, and when the oxygen partial pressure exceeds the above range, the internal electrode layer tends to be oxidized.

The holding temperature at the time of annealing is preferably 1100 ° C. or less, particularly preferably 500 to 1100 ° C. If the holding temperature is lower than the above range, the oxidation of the dielectric layer becomes insufficient, so that the IR is low and the IR life tends to be short. On the other hand, when the holding temperature exceeds the above-mentioned range, not only the internal electrode layer is oxidized and the capacity is reduced, but also the internal electrode layer reacts with the dielectric substrate, so that the capacity-temperature characteristic deteriorates and I
A reduction in R and a reduction in IR life are likely to occur. Note that the annealing may include only the temperature increasing process and the temperature decreasing process. That is, the temperature holding time may be set to zero. In this case, the holding temperature is synonymous with the maximum temperature.

Various conditions other than the above conditions are preferably selected from the following ranges. Temperature holding time: 0 to 20 hours, especially 6 to 10 hours, Cooling rate: 50 to 500 ° C / hour, especially 100 to 300
° C / hour It is preferable to use a humidified N ₂ gas or the like as the atmosphere gas.

In the above-described binder removal processing, firing and annealing, for example, a wetter may be used to humidify the N ₂ gas or the mixed gas. in this case,
The water temperature is preferably about 5 to 75C.

The binder removal processing, firing and annealing are performed as follows.
It may be performed continuously or independently. When these are continuously performed, after removing the binder, the atmosphere is changed without cooling, and then the temperature is raised to the holding temperature at the time of firing, firing is performed, and then cooling is performed, and the temperature reaches the holding temperature of annealing. It is preferable to perform the annealing while changing the atmosphere. On the other hand, when performing these independently, at the time of firing, after raising the temperature under N ₂ gas atmosphere with N ₂ gas or wet to the holding temperature of the binder removal processing, further continuing the heating to change the atmosphere After cooling to the holding temperature at the time of annealing, it is preferable to change to an N ₂ gas or humidified N ₂ gas atmosphere again and continue cooling. In annealing, N ₂
After the temperature is raised to the holding temperature in the gas atmosphere, the atmosphere may be changed, or the entire annealing process may be performed in a humidified N ₂ gas atmosphere.

The end surface of the capacitor element body obtained as described above is polished by, for example, barrel polishing or sand blasting, and the external electrode paste is printed or transferred and baked to form the external electrode 4. The firing condition of the external electrode paste is preferably, for example, about 600 minutes to about 800 ° C. for about 10 minutes to about 1 hour in a humidified mixed gas of N ₂ and H ₂ . Then, if necessary, a coating layer is formed on the surface of the external electrode 4 by plating or the like.

The multilayer ceramic capacitor of the present invention manufactured as described above is used at a temperature of 80 ° C. or more, particularly 125 ° C. or more and 150 ° C. or less. 12 like this
Even at a temperature of 5 ° C. or more and 150 ° C. or less, the rate of change in capacitance with temperature satisfies the EIA standard R characteristic. Further, even when an electric field strength of 0.02 V / μm or more, particularly 0.2 V / μm or more and 0.5 V / μm or more and a DC electric field of 5 V / μm or less are superimposed upon use, the rate of change of the capacitance temperature is obtained Is stable.

The multilayer ceramic capacitor of the present invention manufactured as described above is mounted on a printed circuit board or the like by soldering or the like, and is used for various electronic devices and the like.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, the dielectric porcelain composition obtained by the production method according to the present invention is not limited to being used only for a multilayer ceramic capacitor, but may be used for other electronic components on which a dielectric layer is formed.

[0088]

EXAMPLES Hereinafter, the present invention will be described based on more detailed examples, but the present invention is not limited to these examples.

Example 1 A sample of a multilayer ceramic capacitor was manufactured by the following procedure. First, the following pastes were prepared.

[0090]Paste for dielectric layer Each of the main component raw materials (BaTiO 3) having a particle size of 0.1 to 1 μm
₃) And minor component raw materials were prepared. MgO and Mn
Carbonate is used for the raw material of O, and oxide is used for the other raw materials.
Was. The raw material of the second subcomponent includes (Ba)_0.6Ca
_0.4) SiO₃Was used. Note that (Ba_0.6
Ca_0.4) SiO₃Is BaCO ₃, CaCO
₃And SiO₂For 16 hours by ball mill
After mixing, drying and firing in air at 1150 ° C,
By wet grinding with a ball mill for 100 hours.
Manufactured. In addition, CaZrO as the sixth subcomponent is used.
₃Is CaCO₃And ZrO₃To ball mill
After 16 hours wet mixing and drying, in air at 1150 ° C
And then wet crushing for 24 hours with a ball mill
It was manufactured by doing.

[0091] First, as the main component BaTiO _3, and MgCO ₃ which is a raw material of the first subcomponent are mixed, and dried to prepare a pre-calcination powder. As shown in Table 1, the powder before calcining was 0.9 mol of Mg with respect to 100 mol of BaTiO ₃ (in the table, BT).
CO ₃ was contained. The molar ratio of the specific component in the powder before calcination: (Ba + Mg + Ca) / (Ti + Z
r + Yb + Y), as shown in Table 1,
1.009 and (Ba + Ca + Yb + Y) / (Ti
+ Mg + Zr) was 0.991.

Next, the powder before calcining was calcined. The calcination conditions were as follows. Temperature rising rate: 300 ° C./hour, holding temperature (T1 in Table 2): 900 ° C., temperature holding time: 2 hours, atmosphere: in air.

The material obtained by the calcining was made of aluminum.
Pulverized with narole to obtain a calcined powder,
As shown in Table 2, 3.0 mol of (B
a_{0 . 6}Ca_0.4) SiO₃(In the table, BCG
0.374 mol of MnCO₃,
0.1 mole V₂O₅, 1.0 mol of Yb
₂O₃ , 2.0 moles of Y₂O₃And 1.0 mol
CaZrO₃And wet with a ball mill at 16 o'clock.
Dry after mixing formula, dielectric porcelain composition powder of final composition
I got a body. In the table, CaZrO₃Is represented by CZ
ing.

100 parts by weight of the dielectric ceramic composition powder thus obtained, 4.8 parts by weight of acrylic resin, 40 parts by weight of methylene chloride, 20 parts by weight of ethyl acetate, and 6 parts by weight of mineral spirit And 4 parts by weight of acetone were mixed with a ball mill to form a paste.

100 parts by weight of Ni particles having an average particle diameter of 0.2 to 0.8 μm for an internal electrode layer paste, 40 parts by weight of an organic vehicle (8 parts by weight of ethyl cellulose dissolved in 92 parts by weight of butyl carbitol); 10 parts by weight of butyl carbitol was kneaded with a three-roll mill to form a paste.

100 parts by weight of Cu particles having an average particle size of 0.5 μm for the external electrode paste, 35 parts by weight of an organic vehicle (8 parts by weight of ethyl cellulose resin dissolved in 92 parts by weight of butyl carbitol) and 7 parts by weight of butyl carbitol And kneaded to form a paste.

Preparation of Green Chip The above dielectric layer paste was used to form a green chip on a PET film.
A green sheet having a thickness of 15 μm was formed. 15μ thick
After printing the internal electrode paste on the surface of the m green sheet, the sheet was peeled off from the PET film. Next, the green sheet 4 after printing the internal electrode layer paste
The layers were sandwiched between protective green sheets (without printing the internal electrode layer paste) having a thickness of 15 μm and laminated, and then pressed to obtain a green chip.

Firing First, the green chip is cut into a predetermined size, and after performing binder removal processing, firing and annealing under the following conditions,
External electrodes were formed to obtain a sample of the multilayer ceramic capacitor having the configuration shown in FIG.

Debinding Process Conditions Temperature rise rate: 15 ° C./hour, holding temperature: 280 ° C., temperature holding time: 8 hours, atmosphere: in air.

Firing conditions Temperature rising rate: 200 ° C./hour, holding temperature (T2 in Table 2): temperature shown in Table 2, temperature holding time: 2 hours, cooling rate: 300 ° C./hour, atmosphere gas: humidified N ₂ + _{H 2} mixed gas, oxygen partial pressure: ^{10 -9} atm.

Annealing condition holding temperature: 900 ° C., temperature holding time: 9 hours, cooling rate: 300 ° C./hour, atmosphere gas: humidified N ₂ gas, oxygen partial pressure: 10 ⁻⁵ atm. A wetter with a water temperature of 35 ° C. was used for humidification of the atmosphere gas.

External Electrode The external electrode is obtained by polishing the end face of the fired body by sandblasting, transferring the above-mentioned external electrode paste to the end face, and firing at 800 ° C. for 10 minutes in a humidified N ₂ + H ₂ atmosphere. Formed.

[0103] The sample size of this way, each sample thus obtained is 3.2
mm × 1.6 mm × 0.6 mm, the number of dielectric layers sandwiched between the internal electrode layers is 4, the thickness thereof is 10 μm,
The thickness of the internal electrode layer was 1.5 μm.

In addition to the capacitor samples, disk-shaped samples were also prepared. This disk-shaped sample had the same composition as the dielectric layer of the capacitor sample and the same sintering conditions, and was formed by coating an In-Ga electrode having a diameter of 5 mm on both surfaces of the sample. The following characteristics were evaluated for each sample. Relative dielectric constant (εr), dielectric loss (tanD) The capacitance and ta of a disc-shaped sample at 25 ° C. under the conditions of 1 kHz and 1 Vrms by an LCR meter.
The nD was measured. Then, the relative dielectric constant was calculated from the capacitance, the electrode dimensions, and the thickness of the sample. Table 3 shows the results. The higher the relative permittivity, the better. The lower the dielectric loss, the better.

Insulation Resistance (ρ) The specific resistance at 25 ° C. was measured for a sample of the multilayer chip capacitor. The specific resistance was measured using an insulation resistance tester (R8340A manufactured by Advantest Co., Ltd.) (50 V-1
Value)). Table 3 shows the results. The higher the insulation resistance, the better. The CR product in Table 3 is the product of the dielectric constant and the insulation resistance. CaZrO ₃ in dielectric porcelain composition
FIG. 4 shows an example of the relationship between the content of NR and the CR product.

Breakdown voltage (VB) The breakdown voltage was measured by applying a DC voltage to a sample of a four-layer multilayer chip capacitor at a boosting speed of 100 V / sec and observing a leakage current of 100 mA. I asked by doing. Table 3 shows the results. The higher the breakdown voltage, the better.

IR life under DC electric field (high temperature accelerated life) An acceleration test was performed on a sample of the multilayer chip capacitor at 200 ° C. under an electric field of 18 V / μm, and the insulation resistance was 1%.
The time required to reach MΩ or less was defined as the life time. Table 3 shows the results. The longer the life, the better the durability of the capacitor.

Temperature characteristics of capacitance : -55 to 16
The capacity was measured in a temperature range of 0 ° C., and it was examined whether or not the X8R characteristics were satisfied. Further, an LCR meter was used for the measurement, and the measurement voltage was 1 V.

[0109]

[Table 1]

[0110]

[Table 2]

[0111]

[Table 3]

[0112] and BaTiO ₃ is Embodiment 2 main components, and MgCO ₃ which is a raw material of the first subcomponent, and CaZrO ₃ is a sixth sub ingredients are mixed and dried, the calcination powder body Got ready. As shown in Table 1, the powder before calcination was 100 mol of B
against aTiO _3, and 0.9 mole of MgCO _3,
1.0 mol of CaZrO ₃ . The molar ratio of the specific component in the powder before calcining: (Ba + M
g + Ca) / (Ti + Zr + Yb + Y) was found to be 1.009 and (Ba + C) as shown in Table 1.
a + Yb + Y) / (Ti + Mg + Zr) was 0.991.

Next, the pre-calcined powder was calcined. As shown in Table 2, 3.0 mol of (B) was added to the calcined powder.
a _0.6 Ca _0.4 ) SiO ₃ , 0.374 mol of MnCO ₃ , 0.1 mol of V ₂ O ₅ , 1.0 mol of Yb ₂ O ₃ and 2.0 mol of Y ₂ O ₃ Except for the addition, a columnar sample and a capacitor sample were prepared in the same manner as in Example 1 above.
The same test was performed. Table 3 shows the results.

[0114] and BaTiO ₃ is Embodiment 3 main component, and MgCO ₃ which is a raw material of the first auxiliary component, a _Y 2 _{O 3} is a fifth subcomponent,
The powder before calcining was prepared by mixing with CaZrO _{3 as} the sixth subcomponent and drying. As shown in Table 1, the powder before calcination was 0.9 mol of MgCO ₃ and 2.0 mol of Y ₂ with respect to 100 mol of BaTiO ₃ .
O ₃ and 1.0 mole of CaZrO ₃ were contained. Further, the molar ratio of the specific component in the powder before calcination:
When (Ba + Mg + Ca) / (Ti + Zr + Yb + Y) was examined, it was 0.989, as shown in Table 1,
(Ba + Ca + Yb + Y) / (Ti + Mg + Zr) was 1.011.

Next, the powder before calcining was calcined, and as shown in Table 2, 3.0 mol of (B) was added to the calcined powder.
a _0.6 Ca _0.4 ) SiO ₃ , 0.374 mol of MnCO ₃ , 0.1 mol of V ₂ O ₅ , 1.0 mol of Yb ₂ O ₃ Similarly, a columnar sample and a capacitor sample were prepared, and the same test as in Example 1 was performed. Table 3 shows the results.

[0116] and BaTiO ₃ is Embodiment 4 main components, and MgCO ₃ which is a raw material of the first subcomponent, fourth a subcomponent _Yb 2 O
₃ and CaZrO _{3 as} a sixth subcomponent,
By drying, powder before calcination was prepared. As shown in Table 1, the powder before calcining was 100 mol of BaTiO ₃
In contrast, 0.9 mol of MgCO ₃ , 1.0 mol of Yb ₂ O ₃ and 1.0 mol of CaZrO ₃ were contained. The molar ratio of the specific component in the powder before calcination: (Ba + Mg + Ca) / (Ti + Zr + Yb +
Y) was 0.989, as shown in Table 1, and was found to be (Ba + Ca + Yb + Y) / (Ti + Mg + Z).
r) was 1.011.

Next, the powder before calcining was calcined, and 3.0 mol of (B) was added to the calcined powder as shown in Table 2.
a _0.6 Ca _0.4 ) SiO ₃ , 0.374 mol of MnCO ₃ , 0.1 mol of V ₂ O ₅ , 2.0 mol of Y ₂ O ₃ Similarly, a columnar sample and a capacitor sample were prepared, and the same test as in Example 1 was performed. Table 3 shows the results
Shown in

[0118]Example 5 BaTiO as the main component₃And the raw material of the first subcomponent
MgCO₃And the fourth subcomponent Yb₂O
₃And the fifth subcomponent Y₂O₃And the sixth subcomponent
CaZrO₃By mixing and drying
And calcined powder was prepared. As shown in Table 1, before calcining
The powder is 100 moles of BaTiO₃For 0.9
Molar MgCO₃And 1.0 mole of Yb₂O
₃And 2.0 moles of Y ₂O₃And 1.0 mole of C
aZrO₃Was contained. Also, this calcined powder
Molar ratio of specific component in body: (Ba + Mg + Ca) / (T
i + Zr + Yb + Y), as shown in Table 1.
0.952, and (Ba + Ca + Yb + Y) /
(Ti + Mg + Zr) was 1.051.

Next, the pre-calcined powder was calcined, and 3.0 mol of (B) was added to the calcined powder as shown in Table 2.
a _0.6 Ca _0.4 ) SiO ₃ , 0.374 mol of MnCO ₃ , and 0.1 mol of V ₂ O ₅ were added in the same manner as in Example 1 except that a cylindrical sample and a capacitor were added. And the same test as in Example 1 was performed. Table 3 shows the results.

[0120]Example 6 BaTiO as the main component₃And the raw material of the first subcomponent
MgCO₃And the third subcomponent V₂O₅When,
Yb which is the fourth subcomponent₂O₃And the fifth subcomponent
Y₂O₃And CaZrO as the sixth subcomponent₃When,
MnCO as a raw material of the seventh subcomponent₃And mix and dry
Thus, a powder before calcining was prepared. See Table 1
As described above, the powder before calcination is made of 100 mol of BaTiO.₃To
And 0.9 mol of MgCO₃And 0.374 mole of
MnCO₃And 0.1 mol of V ₂O₅And 1.0
Mole of Yb₂O₃And 2.0 moles of Y₂O
₃And 1.0 mole of CaZrO₃And contain
Was. The molar ratio of the specific component in the powder before calcining: (B
a + Mg + Ca) / (Ti + Zr + Yb + Y)
However, as shown in Table 1, it is 0.952, and (Ba
+ Ca + Yb + Y) / (Ti + Mg + Zr) is 1.05
It was one.

Next, the powder before calcining was calcined, and 3.0 mol of (B) was added to the calcined powder as shown in Table 2.
a _0.6 Ca _0.4 ) A columnar sample and a capacitor sample were prepared in the same manner as in Example 1 except that SiO ₃ was added, and the same test as in Example 1 was performed. Table 1 shows the results.

Example 7 A powder before calcining was prepared by mixing and drying only BaTiO _{3 as a} main component. Molar ratio of specific component in this powder before calcining: (Ba + Mg + Ca) / (Ti + Z
r + Yb + Y), as shown in Table 1,
1.000, (Ba + Ca + Yb + Y) / (Ti
+ Mg + Zr) was 1.000.

Next, the powder before calcination is calcined,
As shown in Table 2, 3.0 mol of (B
a_0.6Ca_0.4) SiO₃, 0.9 mol M
gCO₃0.374 mol of MnCO₃, 0.1 m
Le V₂O₅, 1.0 mol of Yb₂O₃2.
0 moles of Y₂O₃And 1.0 mole of CaZrO
₃Was added in the same manner as in Example 1 except that
Prepare a columnar sample and a capacitor sample, and
The same test as in Example 1 was performed. Table 3 shows the results. Ma
In addition, in this example, the additive (Y
FIG. 7 shows the degree of dispersion of (b, Y, Mg, Ca). further,
In this example, the TEM observation image of the calcined powder was
As shown in FIG. Note that, in FIG.
As for the V value (%), the lower the value, the better the degree of dispersion.
Indicates that C. V value is the value of X-ray in EPMA analysis.
A histogram of the count values is created, and its standard deviation σ and
And an average value x were determined. V = σ / x. Ma
The TEM observation image is a product number JEM- manufactured by JEOL Ltd.
Photographed using 3010. In addition, for TEM observation
After dispersing the powder sample in ethanol,
Made by dropping on an icro grid and drying
did.

[0124]Comparative Example 1 As shown in Tables 1 and 2, the main component was not calcined.
BaTiO₃: 0.9 mol of M to 100 mol
gCO₃0.374 mol of MnCO₃3.0 m
(Ba_0.6Ca_0.4) SiO₃, 0.1
Mole V₂O ₅, 1.0 mol of Yb₂O₃,
2.0 moles of Y₂O₃And 1.0 mole of CaZr
O₃Except that firing was performed using a mixed powder containing
The same as in Example 1 above,
Prepare a sample of the capacitor and conduct the same test as in Example 1.
Was done. Table 3 shows the results. The characteristics of this composition
Molar ratio of constant component: (Ba + Mg + Ca) / (Ti + Zr
+ Yb + Y), as shown in Table 1, 1.
000 and (Ba + Ca + Yb + Y) / (Ti + M
g + Zr) was 1.000.

FIG. 7 shows the degree of dispersion of the additives (Yb, Y, Mg, Ca) in the powder after mixing and before firing in Comparative Example 1. Further, in Comparative Example 1, a TEM observation image of the powder after mixing and before firing is shown in FIG.

[0126] and BaTiO ₃ is a comparative example 2 the main component, and MgCO ₃ which is a raw material of the first subcomponent, a second subcomponent _{(Ba 0.6} C
a _0.4 ) SiO ₃ was mixed and dried to prepare a powder before calcination (not including CZ). As shown in Table 1, the powder before calcination contained 100 moles of BaTiO _3.
In contrast, 0.9 mol of MgCO ₃ and 3.0 mol of (Ba _0.6 Ca _0.4 ) SiO ₃ were contained. Further, the molar ratio of the specific component in the powder before calcination:
When (Ba + Mg + Ca) / (Ti + Zr + Yb + Y) was examined, it was 1.009, as shown in Table 1,
(Ba + Ca + Yb + Y) / (Ti + Mg + Zr) was 0.991.

Next, the pre-calcined powder was calcined, and 3.0 mol of (B) was added to the calcined powder as shown in Table 2.
a _0.6 Ca _0.4 ) SiO ₃ , 0.374 mol of MnCO ₃ , 0.1 mol of V ₂ O ₅ , 1.0 mol of Yb ₂ O ₃ and 2.0 mol of Y ₂ O ₃ Except for the addition (excluding CZ), a cylindrical sample and a capacitor sample were prepared in the same manner as in Example 1, and the same test as in Example 1 was performed. Table 3 shows the results. Example 8 As shown in Tables 1 and 2, a cylindrical sample and a capacitor sample were prepared in the same manner as in Example 4 except that CZ was added at the time of coating. The test was performed. Table 3 shows the results.

Example 9 As shown in Tables 1 and 2, a cylindrical sample and a capacitor sample were prepared in the same manner as in Example 3 except that CZ was added at the time of coating. The same test was performed. Table 3 shows the results.

Example 10 As shown in Tables 1 and 2, a cylindrical sample and a capacitor sample were prepared in the same manner as in Example 5 except that CZ was added at the time of coating. The same test was performed. Table 3 shows the results.

Example 11 As shown in Tables 1 and 2, a columnar sample and a capacitor sample were prepared in the same manner as in Example 6 except that CZ was added at the time of coating. The same test was performed. Table 3 shows the results.

Example 12 As shown in Tables 1 and 2, M as the raw material of the first subcomponent
A columnar sample and a capacitor sample were prepared in the same manner as in Example 1 except that CZ was added to the powder before calcining instead of gCO ₃ , and the same test as in Example 1 was performed. . Table 3 shows the results.

Reference Example 1 A cylindrical sample and a capacitor sample were prepared in the same manner as in Example 6 except that the calcination temperature (T1) was set at 600 ° C., and the same test as in Example 1 was performed. went. Table 3 shows the results. FIG. 7 shows the degree of dispersion of the additives (Yb, Y, Mg, Ca) in the calcined powder in this reference example. Further, in this reference example, a TEM observation image of the calcined powder is shown in FIG.

Example 13 A cylindrical sample and a capacitor sample were prepared in the same manner as in Example 6 except that the calcination temperature (T1) was set at 700 ° C., and the same test as in Example 1 was performed. went. Table 3 shows the results. FIG. 7 shows the degree of dispersion of the additives (Yb, Y, Mg, Ca) in the calcined powder in this example. Further, in this example, a TEM observation image of the calcined powder is shown in FIG.

Example 14 A cylindrical sample and a capacitor sample were prepared in the same manner as in Example 6 except that the calcination temperature (T1) was set to 800 ° C., and a test similar to that in Example 1 was performed. went. Table 3 shows the results. FIG. 7 shows the degree of dispersion of the additives (Yb, Y, Mg, Ca) in the calcined powder in this example. Further, in this example, a TEM observation image of the calcined powder is shown in FIG.

Example 15 A cylindrical sample and a capacitor sample were prepared in the same manner as in Example 6 except that the calcination temperature (T1) was set to 1000 ° C., and a test similar to that in Example 1 was performed. went.
Table 3 shows the results. FIG. 7 shows the degree of dispersion of the additives (Yb, Y, Mg, Ca) in the calcined powder in this example. Further, in this example, a TEM observation image of the powder after calcining is shown in FIG.

Example 16 A cylindrical sample and a capacitor sample were prepared in the same manner as in Example 6 except that the calcination temperature (T1) was set at 1100 ° C., and the same test as in Example 1 was performed. went.
Table 3 shows the results. FIG. 7 shows the degree of dispersion of the additives (Yb, Y, Mg, Ca) in the calcined powder in this example. Further, in this example, a TEM observation image of the calcined powder is shown in FIG.

Reference Example 2 A cylindrical sample and a capacitor sample were prepared in the same manner as in Example 6 except that the calcination temperature (T1) was 1200 ° C., and a test similar to that in Example 1 was performed. went.
Table 3 shows the results.

[0138] and BaTiO ₃ is an embodiment 17 the main component, and MgCO ₃ which is a raw material of the first auxiliary component, and _V 2 _{O 5} as a third subcomponent,
By mixing and drying the fourth subcomponent Yb ₂ O ₃ and the seventh subcomponent raw material MnCO ₃ ,
Powder before calcining was prepared. As shown in Table 1, the powder before calcination was composed of 3.5 mol of MgCO ₃ , 0.374 mol of MnCO _3, and 100 mol of BaTiO ₃ .
0.1 mole of V ₂ O ₅ and 1.0 mole of Yb ₂ O
₃ was contained. Further, the molar ratio of the specific component in the powder before calcination: (Ba + Mg + Ca) / (Ti + Zr)
+ Yb + Y), as shown in Table 1, 1.
015 and (Ba + Ca + Yb + Y) / (Ti + M
g + Zr) was 0.986. Next, the powder before calcination is calcined at 1000 ° C.
As shown in Table 2, 3.0 mol of (Ba _0.6 Ca
_0.4 ) SiO ₃ and 1.0 mole of CaZrO ₃
Was added and calcined at 1320 ° C., and a columnar sample and a capacitor sample were prepared in the same manner as in Example 1, and the same test as in Example 1 was performed. Table 1 shows the results.

[0139] and BaTiO ₃ is an embodiment 18 the main component, and MgCO ₃ which is a raw material of the first auxiliary component, and _V 2 _{O 5} as a third subcomponent,
By mixing and drying the fourth subcomponent Yb ₂ O ₃ and the seventh subcomponent raw material MnCO ₃ ,
Powder before calcining was prepared. As shown in Table 1, the powder before calcination was composed of 3.0 mol of MgCO ₃ , 0.374 mol of MnCO _3, and 100 mol of BaTiO ₃ .
0.1 mole of V ₂ O ₅ and 0.5 mole of Yb ₂ O
₃ was contained. The molar ratio of the specific component in the powder before calcination: (Ba + Mg + Ca) / (Ti + Zr
+ Yb + Y), as shown in Table 1, 1.
020 and (Ba + Ca + Yb + Y) / (Ti + M
g + Zr) was 0.981. Next, the calcined powder was calcined at 1000 ° C.
As shown in Table 2, 3.0 mol of (Ba _0.6 Ca
_0.4 ) SiO ₃ and 1.0 mole of CaZrO ₃
Was added and calcined at 1320 ° C., and a columnar sample and a capacitor sample were prepared in the same manner as in Example 1, and the same test as in Example 1 was performed. Table 1 shows the results.

[0140] and BaTiO ₃ is an embodiment 19 the main component, and MgCO ₃ which is a raw material of the first auxiliary component, and _V 2 _{O 5} as a third subcomponent,
Yb ₂ O ₃ as a fourth sub-component, Y ₂ O _{3 as} a fifth sub-component, and MnCO _{3 as} a raw material of a seventh sub-component
And dried, to prepare a powder before calcination. As shown in Table 1, the powder before calcination was 100 mol of B
against aTiO _3, and 3.0 mole of MgCO _3,
0.374 mol of MnCO ₃ and 0.1 mol of V ₂
And O _5, 0.5 moles of _Yb 2 _{O 3,} had been contained and a 0.5 mole _Y 2 _{O 3.} Further, the molar ratio of the specific component in the powder before calcination: (Ba + Mg + Ca) / (T
When (i + Zr + Yb + Y) was examined, as shown in Table 1, it was 1.010, and (Ba + Ca + Yb + Y) /
(Ti + Mg + Zr) was 0.990. Next, the powder before calcining was calcined at 1000 ° C., and as shown in Table 2, 3.0 mol of (Ba) was added to the calcined powder.
_0.6 Ca _0.4 ) SiO ₃ and 1.0 mol of C
A columnar sample and a capacitor sample were prepared in the same manner as in Example 1 except that aZrO ₃ was added and calcined at 1320 ° C., and the same test as in Example 1 was performed. Table 1 shows the results.

[0141]Reference Example 3 BaTiO as the main component₃For 100 moles, the first
MgCO which is a raw material of subcomponent₃And 1.0 mol
(Ba as an accessory component_0.6Ca_0.4) SiO
₃And 3.0 moles of V as the third subcomponent₂O₅To
0.1 mol and the fourth subcomponent Yb₂O₃To 2.
13 moles and the fifth subcomponent Y₂O₃ 2.0 mol
And CaZrO as the sixth subcomponent₃From 0 to 6.0 mol
And MnCO which is a raw material of the seventh subcomponent₃0.374
Example 2 except that calcination was not performed using mol
In the same manner as in 1, CaZrO₃Dielectric with different contents of
Capacitors having a dielectric layer composed of a ceramic composition
Sensor samples were prepared. For those samples
Then, a CR product was obtained in the same manner as in Example 1. CaZrO
₃FIG. 4 shows the relationship between the content of and the CR product. As shown in FIG.
As described above, the range of CZ is from 0 to 5 mol (however, 0 includes
Was confirmed to be preferable.

Reference Example 4 In the same manner as in Reference Example 3, C was added in the range of 0.5 to 5.0 mol.
A plurality of capacitor samples each having a dielectric layer composed of a dielectric ceramic composition having a different content of aZrO ₃ were prepared, and the capacitance was measured in a temperature range of −55 to 160 ° C.
It was examined whether the 8R characteristic was satisfied. As shown in FIG. 5, it was confirmed that when the CZ was in the range of 0.5 to 5 mol, the X8R characteristics were satisfied. FIG. 5 also shows a rectangular range satisfying the X8R characteristic.

Example 20 As a second subcomponent, instead of 3.0 mol of BCG,
Example 14 except that 3.0 mol of Li ₂ O—BaO—SiO ₂ mixed powder (molar ratio 2: 4: 4) was used.
In the same manner as in the above, a columnar sample and a capacitor sample were prepared, and the same test as in Example 14 was performed. Table 4 shows the results.

Comparative Example 3 As a second subcomponent, instead of 3.0 mol of BCG,
A columnar sample and a capacitor sample were prepared in the same manner as in Comparative Example 1 except that a 3.0 mol Li ₂ O—BaO—SiO ₂ mixed powder (molar ratio 2: 4: 4) was used. Then, the same test as in Comparative Example 1 was performed. Table 4 shows the results.

[0145]Example 21 As a second subcomponent, instead of 3.0 moles of BCG,
3.0 moles of B₂O₃ -BaO-SiO₂Mixed powder
(Molar ratio 1: 4.5: 4.5) except that
In the same manner as in Example 14, a cylindrical sample and a capacitor
And the same test as in Example 14 was performed.
Was. Table 4 shows the results.

[0146]Comparative Example 4 As a second subcomponent, instead of 3.0 moles of BCG,
3.0 moles of B₂O₃ -BaO-SiO₂Mixed powder
(Molar ratio 1: 4.5: 4.5) except that the above ratio was used.
As in Comparative Example 1, the cylindrical sample and the capacitor
A sample was prepared, and the same test as in Comparative Example 1 was performed.
Table 4 shows the results.

Example 22 As a second subcomponent, instead of 3.0 mol of BCG,
Example 14 except that 3.0 mol of Li ₂ O—BaO—SiO ₂ mixed powder (molar ratio 4: 2: 4) was used.
In the same manner as in the above, a columnar sample and a capacitor sample were prepared, and the same test as in Example 14 was performed. Table 4 shows the results.

Comparative Example 5 As a second subcomponent, instead of 3.0 mol of BCG,
3.0 mol of _{Li 2} O-BaO-SiO 2 mixed powder (molar ratio 4: 2: 4) except for using, in the same manner as in Comparative Example 1, prepared a cylindrical sample, and a sample of the capacitor Then, the same test as in Comparative Example 1 was performed. Table 4 shows the results.

[0149]

[Table 4]

As shown in Evaluation Tables 1 to 3, when Examples 1 to 7 of the present invention are compared with Comparative Example 1, there is no significant difference in dielectric constant, dielectric loss, CR product, and the like. As shown in (1), the bias characteristics (DC bias characteristic (DC voltage application dependency of dielectric constant) and TC bias characteristic (capacitance temperature characteristic when DC voltage is applied)) are significantly improved in the example as compared with the comparative example. I was able to confirm. In FIG. 6, the graph of the black dots on the upper side shows the normal temperature characteristics, and the graph of the white dots on the lower side shows the temperature characteristics when a DC electric field of 5 V / μm is applied.

In particular, Examples 3 to 6, 8 to 11, and 13 to 1
As shown in 6, the molar ratio of the components contained in the powder before calcining: (Ba + Mg + Ca) / (Ti + Zr + Yb + Y)
Is less than 1, or (Ba + Ca + Yb + Y) / (Ti +
When Mg + Zr) exceeded 1, it was confirmed that the IR life was particularly improved as compared with the other examples.

As can be seen from a comparison between Example 1 and Example 7, when preparing the powder before calcination, the powder before calcination contains MgCO, which is the raw material of the first subcomponent. It was confirmed that the inclusion of ₃ improved the CR product.

As can be seen by comparing Examples 3 to 6 with the other examples, the number of moles of MgCO ₃ as the raw material of the first subcomponent contained in the powder before calcining was Yb ₂ O _{3 as} a fourth subcomponent and Y ₂ O as a fifth subcomponent
It was confirmed that when the total number of moles was smaller than ₃ , the IR life was improved.

As can be seen from a comparison between Example 2 and Comparative Example 2, according to the method of the present invention, CaZrO ₃ as the sixth subcomponent is contained in the dielectric ceramic composition. It was confirmed that the CR product could be increased. This became clear also from Reference Example 3 shown in FIG.

By comparing Examples 13 to 16 with Reference Examples 1 and 2, the calcining temperature was 700 to 110.
It was confirmed that a temperature of 0 ° C. was preferable. Note that, with reference to FIG. 7, it was found that the degree of dispersion of Ca was particularly improved by increasing the calcining temperature. 8 to 1
By referring to No. 4, it was confirmed that the sintering and grain growth of the additive started rapidly from the calcination temperature of 900 ° C. or higher. Further, by observing FIGS. 8 to 14, it can be seen that the additive component is reactively fixed to the surface of barium titanate due to calcination, and a pseudo coating with the additive is realized. It has been found.

Further, from the results shown in FIG. 5 and FIG.
In the examples of the present invention, it was confirmed that the X8R characteristics could be satisfied.

Further, Examples 3 to 6 and Examples 1, 2, 7
As can be seen from the comparison, the rare earth element (Y
Or Yb) can be confirmed to improve the IR life characteristics. At the time of calcination, the fifth sub-component Y ₂ O _{3 is} more preferable than the fourth component Yb ₂ O _3.
It was confirmed that by making O ₃ essential, the IR life characteristics were improved.

From the results shown in FIGS. 4 and 5 and Tables 1 to 3, the sample of this embodiment satisfies the X8R characteristic,
In addition, it was found that the relative permittivity and the insulation resistance were sufficiently high, the IR life characteristics were excellent, and the dielectric loss was small. In addition, the sample of the present embodiment has X8R characteristics,
B characteristic of EIAJ standard and X7 of EIA standard
The R characteristics were also satisfied. Furthermore, from the results shown in Table 4,
It was confirmed that the effects of the present invention can be obtained also when a sintering aid mainly containing silicon oxide other than BCG is used as the second subcomponent.

[0159]

As described above, according to the present invention, a dielectric ceramic composition for a multilayer chip capacitor in which a base metal such as Ni and a Ni alloy can be used for an internal electrode can be suitably used, and , Controlling the precipitation of foreign phases other than the main composition, controlling the microstructure of the dielectric, and satisfying the dielectric loss, CR product and I
It is possible to manufacture a dielectric ceramic composition with improved R life and excellent reliability.

[Brief description of the drawings]

FIG. 1 is a sectional view of a multilayer ceramic capacitor.

FIG. 2 is a graph showing a preferable relationship between a fourth sub-component and a sixth sub-component in the dielectric ceramic composition according to one embodiment of the present invention.

FIG. 3 is a flowchart of a method for manufacturing the capacitor shown in FIG. 1 according to an embodiment of the present invention.

FIG. 4 is a graph showing the relationship between the content of a sixth subcomponent and the CR product.

FIG. 5 is a graph showing the capacitance-temperature characteristics of the dielectric ceramic composition obtained according to the example of the present invention.

FIG. 6 is a graph showing capacitance-temperature characteristics and bias characteristics of a dielectric ceramic composition obtained according to an example of the present invention.

FIG. 7 is a graph showing the degree of dispersion of additives in the powder after calcination.

FIG. 8 is a photograph showing a TEM observation image of powder after mixing and before firing in the dielectric ceramic composition according to Comparative Example 1.

FIG. 9 is a photograph showing a TEM observation image of the calcined powder in the dielectric ceramic composition according to Reference Example 1.

FIG. 10 is a photograph showing a TEM observation image of a calcined powder in the dielectric ceramic composition according to Example 13.

FIG. 11 is a photograph showing a TEM observation image of a calcined powder in the dielectric ceramic composition according to Example 14.

FIG. 12 is a photograph showing a TEM observation image of a calcined powder in the dielectric ceramic composition according to Example 7.

FIG. 13 is a photograph showing a TEM observation image of the calcined powder in the dielectric ceramic composition according to Example 15.

FIG. 14 is a photograph showing a TEM observation image of a calcined powder in the dielectric ceramic composition according to Reference Example 2.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Multilayer ceramic capacitor 2 ... Dielectric layer 3 ... Internal electrode layer 4 ... External electrode 10 ... Capacitor element main body

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-5460 (JP, A) JP-A-2000-154057 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C04B 35/42-35/50 CA (STN) REGISTRY (STN)

Claims (10)

(57) [Claims] And 1. A main component consisting of barium titanate, a second subcomponent is a sintering aid, and a sixth subcomponent including CaZrO ₃ or CaO + ZrO _2, and a other subcomponents at least the Excluding the second subcomponent, mixing the main component with at least a part of the sixth subcomponent and other subcomponents to prepare a powder before calcining; Preparing a calcined powder by calcining the pre-powder; and mixing at least the second subcomponent with the calcined powder, wherein a ratio of each subcomponent to the main component is a predetermined molar ratio. a manufacturing method of a dielectric ceramic composition having the steps of: obtaining a dielectric ceramic composition is a barium titanate being the main component expressed by a composition formula Ba _m
TiO _{2 + m} where _m in the above composition formula is 0.99
5 ≦ m ≦ 1.010 and the ratio of Ba to Ti is 0.9
95 ≦ Ba / Ti ≦ 1.010, the second subcomponent is mainly composed of SiO ₂ , and MO (where M is at least one element selected from Ba, Ca, Sr and Mg); Li ₂ O and B ₂ O
_And at least one selected from the group consisting of MgO, CaO, BaO, SrO and Cr ₂ O ₃
A first subcomponent including at least one selected from, a third subcomponent including at least one kind selected from _V 2 _O 5, MoO ₃ and WO _3, an oxide of R1 (however, R1 Sc , Er, Tm, Yb
And at least one selected from Lu)
And at least a sub-component, wherein at least the second sub-component is mixed with the calcined powder, and the ratio of each sub-component with respect to 100 mol of the main component is: first sub-component: 0.1 to 3 Mol, 2nd subcomponent: 2 to 10 mol, 3rd subcomponent: 0.01 to 0.5 mol, 4th subcomponent: 0.5 to 7 mol (however, the number of moles of the 4th subcomponent is R1 A method for producing a dielectric porcelain composition, characterized by obtaining a dielectric porcelain composition in which the sixth subcomponent is 0 to 5 mol (however, 0 is not included). 2. The molar ratio of components contained in the powder before calcination: (Ba + Ca + metal element in first subcomponent) / (Ti
+ Zr + R1) is less than 1 or (Ba + Ca + R1)
2. The dielectric ceramic composition according to claim 1 , wherein the powder before calcining is prepared and calcined so that // (Ti + Zr + metal element in the first subcomponent) exceeds 1. 3. Production method. 3. A main component consisting of barium titanate, 6 comprises a second subcomponent is a sintering aid, CaZrO ₃ or CaO + ZrO ₂ sub
A component and at least other subcomponents, and excluding the second subcomponent with respect to the main component.
6 sub-components and at least part of other sub-components
Mixing the door, preparing a step of preparing a pre-calcination powder, the calcined spent powder was calcined said pre-calcination powder
And at least the second subcomponent is mixed with the calcined powder.
And the ratio of each subcomponent to the main component is a predetermined molar ratio.
A manufacturing method of a dielectric ceramic composition and a step of obtaining a certain dielectric ceramic composition, a barium titanate being the main component, formula Ba _m
TiO _{2 + m} where _m in the above composition formula is 0.99
5 ≦ m ≦ 1.010 and the ratio of Ba to Ti is 0.9
95 ≦ Ba / Ti ≦ 1.010, the second subcomponent is mainly composed of SiO ₂ , and MO (where M is at least one element selected from Ba, Ca, Sr and Mg); Li ₂ O and B ₂ O
_And at least one selected from the group consisting of MgO, CaO, BaO, SrO and Cr ₂ O ₃
A first subcomponent including at least one selected from, a third subcomponent including at least one kind selected from _V 2 _O 5, MoO ₃ and WO _3, an oxide of R1 (however, R1 Sc , Er, Tm, Yb
And at least one selected from Lu)
An auxiliary component and an oxide of R2 (where R2 is Y, Dy, Ho, Tb,
And at least a fifth subcomponent containing at least one selected from Gd and Eu), wherein at least the second subcomponent is mixed with the calcined powder, and each subcomponent with respect to 100 mol of the main component. The ratio of the first subcomponent: 0.1 to 3 mol, the second subcomponent: 2 to 10 mol, the third subcomponent: 0.01 to 0.5 mol, the fourth subcomponent: 0.5 to 7 Mole (however, the number of moles of the fourth subcomponent is a ratio of R1 alone), the fifth subcomponent: 2 to 9 moles (however, the number of moles of the fifth subcomponent is a ratio of R2 alone) ), A sixth subcomponent: a method for producing a dielectric porcelain composition, comprising obtaining a dielectric porcelain composition having 0 to 5 moles (however, 0 is not included). Wherein the molar ratio of the components contained in the pre-calcination in the powder: (Ba + Ca + first metal element in the subcomponent) / (Ti
+ Zr + R1 + R2) is less than 1 or (Ba + Ca +
4. The dielectric ceramic composition according to claim 3 , wherein the powder before calcining is prepared and calcined so that (R1 + R2) / (Ti + Zr + metal element in the first subcomponent) exceeds 1. Method of manufacturing a product. Except wherein said second subcomponent, said main component, the first subcomponent, third subcomponent, fourth subcomponent, at least one of the fifth subcomponent and sixth subcomponent mixing, in preparing pre-calcination powder, the pre-calcination powder, also claim 3, characterized in that to always include the fifth subcomponent
5. The method for producing a dielectric ceramic composition according to item 4 . Except wherein said second subcomponent, said main component, the first subcomponent, third subcomponent, fourth subcomponent, at least one of the fifth subcomponent and sixth subcomponent mixing, in preparing pre-calcination powder, the pre-calcination powder, claim, characterized in that to always include the first subcomponent 3-5
The method for producing a dielectric ceramic composition according to any one of the above. 7. Except for the second subcomponent, the main component and at least one of the first subcomponent, the third subcomponent, the fourth subcomponent, the fifth subcomponent, and the sixth subcomponent. mixing, in preparing pre-calcination powder, the pre-calcination powder, the first subcomponent, claim 3, the fourth subcomponent and the fifth, characterized in that always include a subcomponent manufacturing method of a dielectric ceramic composition according to any one 6 of. 8. moles of the first subcomponent included in the pre-calcination in the powder is the fourth subcomponent and the total number of moles of the fifth subcomponent (note that the fourth subcomponent and the fifth subcomponent The method according to claim 7 , wherein the number of moles is smaller than R1 alone and R2 alone. 9. The pre-calcined powder is heated at 700 to 1100 ° C.
The method for producing a dielectric ceramic composition according to any one of claims 1 to 8 , wherein the calcining is performed at a temperature of: 10. The method for producing a dielectric ceramic composition according to claim 1, wherein the calcining is performed a plurality of times.