JP3417931B2 - Method for producing dielectric porcelain composition and method for producing electronic component - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a dielectric ceramic composition used as, for example, a dielectric layer of a multilayer ceramic capacitor, and an electronic component using the dielectric ceramic composition as a dielectric layer. Regarding the method.

[0002]

2. Description of the Related Art A multilayer ceramic capacitor, which is an example of electronic parts, has a conductive paste printed on a green sheet of a predetermined dielectric ceramic composition, and a plurality of green sheets printed with the conductive paste are stacked. The green sheet and the internal electrodes are integrally fired to be formed.

A conventional dielectric ceramic composition is reduced by firing in a neutral or reducing atmosphere having a low oxygen partial pressure,
It had the property of becoming a semiconductor. For this reason, when manufacturing a monolithic ceramic capacitor, it has been forced to perform firing in an oxidizing atmosphere having a high oxygen partial pressure. Along with this, as an internal electrode material that is fired at the same time as the dielectric ceramic composition, an expensive noble metal that does not melt at the temperature at which the dielectric ceramic composition is sintered and is not oxidized even if fired in an oxidizing atmosphere It is necessary to use (for example, palladium, platinum, etc.), which has been a major obstacle to lowering the price of manufactured multilayer ceramic capacitors.

On the other hand, in order to use an inexpensive base metal (for example, nickel or copper) as a material for the internal electrodes, it does not become a semiconductor even if it is fired at a low temperature in a neutral or reducing atmosphere. It is necessary to develop a dielectric porcelain composition having excellent reducing properties and having a sufficient relative dielectric constant after firing and excellent dielectric properties (for example, a small rate of change in capacitance temperature).

Heretofore, various proposals have been made as a dielectric ceramic composition in which a base metal can be used as a material for the internal electrodes.

For example, JP-A-63-224108
In the report, (Sr_1-xCa_x) _m(Ti_1-y
Zr_y) O_ThreeDielectric oxide of composition shown by
, 0.30 ≦ x ≦ 0.50, 0.03 ≦ y ≦ 0.2
0, 0.95 ≦ m ≦ 1.08) as the main component
With respect to 100 parts by weight of Mn, Mn is added as an accessory component to MnO.
_Two0.01 to 2.00 parts by weight, SiO_TwoTo
A dielectric ceramic composition containing 0.10 to 4.00 parts by weight is
It is disclosed.

Further, in Japanese Patent Application Laid-Open No. 63-224109, there is disclosed a dielectric ceramic composition containing 0.01 to 1.00 parts by weight of ZnO in addition to Mn and SiO ₂ with respect to the main component. It is disclosed.

Further, in Japanese Patent Laid-Open No. 4-206109, (Sr _1-x Ca _x ) _m (Ti _1-y Zr
_y ) A dielectric oxide having a composition represented by O ₃ (provided that
0.30 ≦ x ≦ 0.50, 0.00 ≦ y ≦ 0.20,
Disclosed is a dielectric porcelain composition containing 0.95 ≦ m ≦ 1.08) as a main component and having a powder particle size in the range of 0.1 to 1.0 μm.

Furthermore, Japanese Examined Patent Publication No. 62-24388
In the report, (MeO)_kTiO_TwoDielectric of composition
Body oxide (however, Me is Sr, Ca and Sr + Ca
Mainly selected metal, k is 1.00 to 1.04)
The glass component is added to 100 parts by weight of this main component.
As Li_TwoO, M (however, M is BaO, CaO
And at least one metal oxide selected from SrO
Object) and SiO_Two Was used at a predetermined molar ratio of 0.
A dielectric ceramic composition containing 2 to 10.0 parts by weight is disclosed.
There is.

[0010]

However, when the dielectric porcelain compositions described in these publications are produced by a usual method, the accelerated life of insulation resistance after firing is insufficient, and When a dielectric ceramic composition is used to manufacture a multilayer ceramic capacitor having internal electrodes made of a base metal such as nickel, there is a problem that the reliability of the multilayer ceramic capacitor obtained is low. In addition,
The present inventors have found that the molar ratio m is relatively low, {(Sr
_1-x Ca _x ) O} _m · (Ti _1-y Z
In the composition system represented by r _y ) O ₂ , it has been proposed to add a rare earth component such as yttrium in order to increase the accelerated life of insulation resistance (Japanese Patent Application No. 2000-18).
7800). However, in the case of manufacturing by the usual method, it was difficult to extend the life even if the rare earth component was added, in the range where the molar ratio m was 0.995 ≦ m <1.08, which was a relatively high range.

An object of the present invention is to provide a method for producing a dielectric ceramic composition which has excellent reduction resistance during firing, has excellent capacity-temperature characteristics after firing, and can improve the accelerated life of insulation resistance, and reliability. It is to provide a method for manufacturing an electronic component such as a chip capacitor having improved properties.

[0012]

In order to achieve the above object, a method for producing a dielectric ceramic composition according to the present invention is a compositional formula {(Sr _1-x Ca _x ) O} _m · (Ti
_1-y Zr _y ) O ₂ , the molar ratio m in the composition formula is 0.94 <m <1.08, and the symbol x is 0 ≦.
x is ≤1.00 and the symbol y is 0≤y≤0.20, and an oxide of R (where R is Sc, Y, L
a, Ce, Pr, Nd, Pm, Sm, Eu, Gd, T
b, Dy, Ho, Er, Tm, Yb, and at least one selected from Lu) and a fourth subcomponent, and a method for producing a dielectric porcelain composition, comprising: It is characterized in that the dielectric ceramic composition is manufactured using a composition raw material obtained by previously reacting at least a part of the four subcomponent raw materials.

The method of manufacturing an electronic component according to the present invention has a composition
Expression {(Sr_1-xCa_x) O} _m・ (Ti
_1-yZr_y) O_TwoIt is represented by
The rule ratio m is 0.94 <m <1.08, and the symbol x is 0 ≦
x ≦ 1.00 and the symbol y is 0 ≦ y ≦ 0.20
Main component and oxide of R (where R is Sc, Y, L
a, Ce, Pr, Nd, Pm, Sm, Eu, Gd, T
Select from b, Dy, Ho, Er, Tm, Yb and Lu
And a fourth subcomponent comprising at least one)
Electronic part having a dielectric layer composed of an electric porcelain composition
A method of manufacturing a product, the method comprising:
Composition raw material obtained by pre-reacting at least a part of component raw materials
Is used to produce the dielectric ceramic composition.
And

It is considered that by pre-reacting at least a part of the fourth subcomponent raw material with the main component raw material, the distribution of the fourth subcomponent after the main calcination becomes more uniform (solid solution state). Preferably, the oxide of R contained in the fourth subcomponent is Sc, Y, Ce, Dy, Ho, Er, T.
It is at least one oxide of m, Yb, and Lu.

The reaction method is not limited to a solid phase method such as a calcining method, but may be a liquid phase synthesis method such as an oxalate method, a hydrothermal synthesis method or a sol-gel method. In addition, "at least one part" means at least one part of 4th subcomponent raw material corresponding to the total amount of 4th subcomponent which will be contained in a final composition. However, it is preferable to react all of the fourth subcomponent to be contained in the final composition.

Preferably, a composition raw material in which 100 mol of the main component raw material is previously reacted with 0.02 mol or more and less than 2 mol of the fourth subcomponent raw material in terms of R in the oxide. To use.

Preferably, the main component material is a compositional formula {(Sr _1-x Ca _x ) O} _{m '.} (Ti _1-y
Zr _y ) O ₂ and has a molar ratio m ′ in the above composition formula.
Is m ′ ≦ m with respect to the molar ratio m of the final composition.

Preferably, after adding a substance containing at least one element of Sr and Ca to the composition raw material, more preferably a substance containing at least one element of Sr and Ca without adding a substance containing Ti. After adding, it is baked.

Preferably, the molar ratio m'in the composition formula of the main component raw material is 0.9 <m '.

[0020]

Function: Composition formula {(Sr_1-xCa_x) O}_m・
(Ti_1-yZr_y) O_Two And in particular the composition
The molar ratio m in the formula is relatively high (0.995 ≦ m <1.0
8) Dielectric porcelain having a main component and a specific fourth subcomponent
When the composition is produced by a usual method, the insulation resistance
It is difficult to improve the accelerated life (high temperature load life)
It has been clarified by the present inventors. The original
The cause is the grain boundary part or triple point in the dielectric ceramic composition after firing.
Segregated a large amount of R or R oxide in the fourth subcomponent raw material
However, it is considered that it is not evenly distributed in the grains.
It

In the method for producing a dielectric ceramic composition according to the present invention, the dielectric ceramic composition is prepared by using a composition raw material obtained by previously reacting at least a part of the fourth subcomponent raw material with the main component raw material. By producing, a reduction resistance at the time of firing is excellent, an excellent capacity-temperature characteristic is obtained after firing, and R of the fourth sub ingredient material or R of the fourth sub ingredient material is present in the grain boundaries in the dielectric ceramic composition after firing. Since the oxide of R is uniformly distributed, it is possible to manufacture a dielectric ceramic composition having an accelerated insulation resistance lifetime (for example, 200 ° C., DC 8 V / μm). In particular, the composition formula {(Sr
_1-x Ca _x ) O} _{m ′} · (Ti _1-y Z
When the main component raw material represented by r _y ) O ₂ is used, R of the fourth sub ingredient raw material is added to the dielectric ceramic composition after firing.
Alternatively, the oxide of R tends to be more uniformly distributed, which further improves the accelerated life of the insulation resistance of the obtained dielectric ceramic composition. In addition, in the range where the molar ratio m in the composition formula is relatively low (0.94 <m <0.995), even if the fourth sub ingredient material is not reacted with the main ingredient material in advance, It has been clarified by the present inventors that in the dielectric ceramic composition, the fourth subcomponent is almost uniformly distributed in the grains of the main component. However, even if the molar ratio m is relatively low,
By producing the dielectric ceramic composition using the composition raw material in which the sub-component raw material is preliminarily reacted, the fourth sub-component raw material is not pre-reacted with the main component raw material, that is, with respect to the main component raw material. The fourth subcomponent is more likely to be more evenly distributed in the grains of the main component, as compared with the case where a raw material obtained by post-adding the fourth subcomponent raw material is used. As a result, further improvement in accelerated life of insulation resistance can be expected.

In the method of manufacturing an electronic component according to the present invention, it is possible to manufacture an electronic component such as a chip capacitor having excellent capacitance-temperature characteristics, improved accelerated life of insulation resistance, and improved reliability.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on the embodiments shown in the drawings. FIG. 1 is a sectional view of a monolithic ceramic capacitor according to an embodiment of the present invention. Before describing the method for producing a dielectric ceramic composition according to the present invention, first, a laminated ceramic capacitor will be described.

Monolithic Ceramic Capacitor As shown in FIG. 1, a monolithic ceramic capacitor 1 as an electronic component according to an embodiment of the present invention has a structure in which dielectric layers 2 and internal electrode layers 3 are alternately laminated. It has a capacitor element body 10.

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 usually a rectangular parallelepiped. Further, the size is not particularly limited, and may be an appropriate size according to the application, but normally,
(0.6 to 5.6 mm) x (0.3 to 5.0 mm) x
(0.3 to 1.9 mm).

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

Dielectric Layer 2 The dielectric layer 2 contains the dielectric ceramic composition obtained by the manufacturing method of the present invention. Such a dielectric porcelain composition,
Compositional formula {(Sr _1-x Ca _x ) O} _m · (Ti
_1-y Zr _y ) O ₂ having a main component.
At this time, the amount of oxygen (O) may be slightly deviated from the stoichiometric composition of the above formula.

In the above formula, the symbol x is 0≤x≤1.00,
Preferably 0.30 ≦ x ≦ 0.50. x represents the number of Ca atoms, and the phase transition point of the crystal can be arbitrarily shifted by changing x, that is, the Ca / Sr ratio. Therefore, the temperature coefficient of capacitance and the relative permittivity can be controlled arbitrarily. When x is in the above range, the phase transition point of the crystal exists near room temperature, and the temperature characteristic of capacitance can be improved. However, in the present invention, Sr and C
The ratio with a is arbitrary and may contain only one.

In the above formula, the symbol y is 0≤y≤0.20,
Preferably 0 ≦ y ≦ 0.10. By setting y to 0.20 or less, a decrease in relative permittivity can be prevented. y is Z
Represents the number of r atoms, but is more difficult to reduce than TiO ₂ Z
Reduction resistance tends to be further increased by substituting rO ₂ . However, in the present invention, Zr does not necessarily have to be contained, and only Ti may be contained.

In the above formula, the molar ratio m should be larger than 0.94, preferably 0.995 ≦ m <1.08. By making m larger than 0.94, it is possible to prevent semiconducting from occurring in firing in a reducing atmosphere, and particularly when m is made 0.995 or more, the oxygen partial pressure during firing is made lower. Has a long life, and m is 1.08
When the amount is less than the range, a dense sintered body can be obtained without increasing the firing temperature.

In the dielectric ceramic composition according to the present invention, in addition to the main component represented by the above composition formula, an oxide of R (provided that R is
Is Sc, Y, La, Ce, Pr, Nd, Pm, Sm,
It also has a fourth subcomponent which comprises at least one selected from Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. The fourth subcomponent has the effect of improving the high temperature load life (accelerated life of insulation resistance), and also has an initial insulation resistance (IR) when the dielectric is thinned (for example, about 4 μm).
It also has the effect of improving the defective rate. From the viewpoint of improving the defect rate (the rate of non-defective products in the initial IR is preferably 15% or more), Sc, Y, Ce, Dy, Ho, Er, Tm, Yb.
It is more preferable to contain at least one oxide of Lu and Lu. Relatively high molar ratio m of main component 0.9
Even in the range of 95 ≦ m <1.08, by adding a predetermined amount of the fourth subcomponent at the timing described later, the dielectric characteristics are not deteriorated, and the accelerated life of the insulation resistance of the dielectric layer 2 (high temperature load life) ) Can be improved, and the reliability of the obtained multilayer ceramic capacitor 1 can be significantly improved. Note that the molar ratio m of the main component is relatively low, 0.94 <m <0.
Even in the range of 995, by adding a predetermined amount of the fourth subcomponent at the timing described below, the fourth subcomponent can be added at the timing described below.
The acceleration life (high temperature load life) of the insulation resistance of the dielectric layer 2 is improved as compared with the case where no subcomponent is added.

The ratio of the fourth subcomponent with respect to 100 mol of the main component is 0.02 mol ≦ fourth subcomponent <2 mol, preferably 0.02 ≦ fourth subcomponent ≦ 0. It is 6. By setting the ratio of the fourth subcomponent to such a range, the accelerated life of the insulation resistance can be particularly improved in the range where the molar ratio m of the main component is relatively high.

In the present invention, R contained in the fourth subcomponent is
It is preferable that the oxide of (1) contains particles that are substantially uniformly distributed in the particles. In the present invention, a predetermined amount of a fourth subcomponent is contained with respect to the main component, and in particular, particles in which R or an oxide of R in the fourth subcomponent is substantially uniformly distributed in the particles. It is more effective to improve the accelerated life of insulation resistance by containing

The dielectric ceramic composition obtained by the manufacturing method of the present invention for forming the dielectric layer 2 contains V, Nb,
A predetermined amount of the first subcomponent containing at least one selected from oxides of W, Ta and Mo and / or compounds which become these oxides after firing may be added. By adding a predetermined amount of such a first subcomponent, it is possible to perform low temperature firing without deteriorating the dielectric properties, and to improve the accelerated life (high temperature load life) of the insulation resistance even when the dielectric layer is thin. . When the first subcomponent is added, the ratio of the first subcomponent with respect to 100 mol of the main component is 0.01 mol ≦ first subcomponent <2 mol, preferably 0. 04 mol ≦ first subcomponent ≦
It is 0.6 mol.

Further, the dielectric ceramic composition is further added with a second subcomponent containing an oxide of Mn (for example, MnO) and / or a compound (for example, MnCO ₃ ) which becomes an oxide of Mn by firing. May be. This second subcomponent has the effect of promoting sintering and the effect of improving the high temperature load life, and also has an initial insulation resistance (IR) defect rate when the dielectric layer 2 is thinned to, for example, about 4 μm. It also has a reducing effect. When adding the second sub ingredient,
The ratio of the second subcomponent with respect to 100 mol of the main component is 0 mol ≦ second subcomponent <4 mol, preferably 0.05 mol ≦ second subcomponent ≦ 1.4 mol in terms of metal element in the oxide. Is.

Further, the dielectric ceramic composition contains SiO
_Two, MO (where M is Ba, Ca, Sr and M
at least one element selected from g), Li_TwoO oh
And B _TwoO_ThreeIncluding at least one selected from
A predetermined amount of 3 subcomponents may be added. This third sub-product
The component mainly acts as a sintering aid. The third subcomponent
When added, it is based on 100 mol of the main component
The ratio of the third subcomponent is 0 mol <third oxide equivalent
Subcomponent <15 mol, preferably 0.2 mol ≤ third subcomponent
≦ 6 mol.

Various conditions such as the number of laminated layers and the thickness of the dielectric layer 2 shown in FIG. 1 may be appropriately determined according to the purpose and application. The dielectric layer 2 is composed of grains and a grain boundary phase, and the average grain size of the grains of the dielectric layer 2 is 1 to 5 μm.
It is preferable that there is a degree. This grain boundary phase is usually an oxide of the material forming the dielectric material or the internal electrode material,
An oxide of a material added separately, and further, an oxide of a material mixed as an impurity during the process are used as components, and are usually made of glass or glass.

Internal Electrode Layer 3 The conductive material contained in the internal electrode layer 3 is not particularly limited, but a base metal can be used because the constituent material of the dielectric layer 2 has reduction resistance. As the base metal used as the conductive material, Ni or Ni alloy is preferable. The Ni alloy is selected from Mn, Cr, Co and Al 1
An alloy of one or more elements and Ni is preferable, and Ni in the alloy is
The content is preferably 95% by weight or more. In addition,
The Ni or Ni alloy may contain various trace components such as P, Fe and Mg in an amount of about 0.1% by weight or less. The thickness of the internal electrode layer may be appropriately determined according to the application, etc., but is usually 0.5 to 5 μm, and particularly preferably 1 to 2.5 μm.

External Electrode 4 The conductive material contained in the external electrode 4 is not particularly limited, but Cu, Cu alloy, Ni, Ni alloy or the like is usually used. Of course, Ag, Ag-Pd alloy, etc. can also be used. In the present embodiment, inexpensive Ni and C are used.
u and alloys of these are used. The thickness of the external electrode may be appropriately determined according to the application, etc., but is usually 10 to 50 μm.
It is preferably about m.

The multilayer ceramic capacitor 1 produced by using a production method of a dielectric ceramic composition according to the production method the present invention of a multilayer ceramic capacitor is produced by producing a green chip by a normal printing method or sheet method using a paste After firing, the external electrodes are printed or transferred and fired. The manufacturing method will be specifically described below. The dielectric layer paste, the internal electrode paste, and the external electrode paste are manufactured.

Dielectric Layer Paste First, the dielectric ceramic composition raw material contained in the dielectric layer paste is prepared. In the present invention, the dielectric ceramic composition raw material includes a composition raw material in which the fourth subcomponent raw material is preliminarily reacted with the main component raw material. It is considered that the fourth subcomponent raw material is in a solid solution state in the main component raw material of the composition raw material.

The fourth subcomponent material is an oxide of R (where R is Sc, Y, La, Ce, Pr, Nd, P).
m, Sm, Eu, Gd, Tb, Dy, Ho, Er, T
at least one selected from m, Yb and Lu). From the viewpoint of improving the defective rate, Sc, Y, C
It is more preferable to contain at least one oxide of e, Dy, Ho, Er, Tm, Yb and Lu.

In this embodiment, the composition formula is used as the main component raw material.
{(Sr_1-xCa_x) O}_{m '}・ (Ti_1-y
Zr_y) O_TwoThe raw material represented by is used. Also this implementation
In the form, the molar ratio m ′ in the composition formula is expressed by the composition formula {(S
r_1-xCa_x) O}_m ・ (Ti_1-yZ
r_y) O_TwoIn the dielectric ceramic composition after firing represented by
To be smaller than the molar ratio m of the oxide in the composition formula in
(M '<m). However, in the present invention, the raw material stage
Molar ratio m ′ in the floor and the molar ratio in the dielectric ceramic composition after firing
The ratio m may be set to be the same (m '= m). Raw material stage
The molar ratio m'in the above is set to be smaller than the molar ratio m after firing.
By placing the dielectric layer 2, the dielectric porcelain after firing is formed.
Oxidation of R or R of the fourth subcomponent raw material within the grain boundary in the composition
Things are more evenly distributed, which helps
The accelerated life of the insulation resistance of the dielectric ceramic composition
The layers can be improved. The lower limit of the molar ratio m'is the reason for preventing semiconductor formation.
For the reason, preferably set to be larger than 0.9
More preferably 0.92 ≦ m ′ ≦ 1.06, and
Preferably 0.92 ≦ m ′ ≦ 1.02, particularly preferably
0.94 ≦ m ′ ≦ 1.00.

Such a composition formula {(Sr_1-xCa
_x) O}_{m '}・ (Ti_1-yZr _y) O_TwoTable
The main component materials to be used are so-called solid phase method and so-called liquid
It may be obtained by the phase method. Solid-phase method
SrCO_Three, CaCO_Three, TiO_Two, Z
rO_TwoWhen using as a starting material,
Raw materials are obtained by weighing, mixing, calcining and crushing.
Method. Liquid phase synthesis methods include the oxalate method and water.
A thermal synthesis method, a sol-gel method and the like can be mentioned. Note that a mole
Sr_tTiO_ThreeAnd b mol of Ca_{t '}TiO_Three
And c mol of Sr _{t ''}ZrO_ThreeAnd d mol of Ca
_{t '''}ZrO_ThreeWhen combining raw materials by combining
, M'is m '= (at + bt' + ct '' + d
t ′ ″) / (a + b + c + d)
It

In order to react the fourth sub ingredient material with such a main ingredient material, in producing the main ingredient material,
A fourth subcomponent material may be mixed with the starting material to obtain the composition material by a solid phase method, a liquid phase method, or the like. Alternatively, once the main ingredient material is solid phase method or liquid phase method. It is also possible to obtain the composition raw material by manufacturing the above-mentioned material by adding the fourth subcomponent raw material thereto. In any case, it is preferably 0.02 mol or more and less than 2 mol, more preferably 0.02 mol or more and 0.6 mol or less in terms of R in the oxide with respect to 100 mol of the main component raw material. The composition raw material is obtained by previously reacting the fourth subcomponent raw material. By setting the content of the fourth subcomponent raw material within such a range, the accelerated life of the insulation resistance of the obtained dielectric ceramic composition can be improved.

An example of a method of reacting the fourth subcomponent raw material to obtain the raw material of the composition when producing the main component raw material by the solid phase method will be described below.

First, for example, SrCO ₃ , CaCO ₃ , TiO ₂ and ZrO _{2 are provided} so as to have a predetermined m ′.
In addition to the respective main component raw materials such as, a predetermined amount of a fourth subcomponent raw material such as Y ₂ O ₃ is weighed, mixed, and dried to prepare a pre-calcination raw material.

Then, the prepared powder before calcination is calcined. The calcination conditions are not particularly limited, but it is preferable to carry out the following conditions. The temperature rising rate is preferably 50 to
The temperature is 400 ° C./hour, more preferably 100 to 300 ° C./hour. The holding temperature is preferably 500 to 1200.
C., more preferably 700 to 1100.degree. The temperature holding time is preferably 0.5 to 6 hours, more preferably 1 to 3 hours. The treatment atmosphere may be air, nitrogen, or a reducing atmosphere.

Then, the calcined powder that has been calcined is roughly crushed by an alumina roll or the like, and then the compositional formula of the final product {(Sr _1-x Ca _x ) O} _m · (Ti
_1-y Zr _y ) O ₂ to be mixed with the raw material powder. At this time, first to third subcomponent materials may be added if necessary. However, you may add the 1st-3rd subcomponent raw material before calcination. As the first subcomponent raw material, one or more single oxides or composite oxides selected from oxides of V, Nb, W, Ta and Mo and / or compounds that become these oxides after firing are used. . As the second subcomponent raw material, a single oxide or a complex oxide of an oxide of Mn and / or a compound that becomes an oxide of Mn by firing is used. As the third subcomponent raw material, SiO ₂ , MO (where M is Ba, Ca, S
at least one element selected from r and Mg), L
at least 1 selected from i ₂ O and B ₂ O ₃
One is used.

In this embodiment, m '<m (however, m' = m may be used in the present invention), so that the raw material powder for achieving the composition formula of the final product is Sr rather than Ti and / or Zr. And / or Ca-rich substance powder. More preferably, the substance does not contain Ti and / or Zr but contains Sr and / or Ca.

Thereafter, this mixed powder is, if necessary,
By mixing with a ball mill or the like and drying, a dielectric ceramic composition raw material having the composition of the present invention can be obtained.

That is, in the present invention, a dielectric ceramic composition raw material containing a composition raw material in which at least a part of the fourth subcomponent raw material is preliminarily reacted with the main component raw material is used,
By subjecting it to firing to be described later, R in the fourth subcomponent raw material is added to grain boundaries and triple points in the fired dielectric ceramic composition.
Alternatively, the oxide of R does not segregate and is uniformly distributed in the grains, so that the accelerated life of the insulation resistance can be improved.

In particular, in this embodiment, the molar ratio m ′ of the main component raw material is set to be smaller than the molar ratio m after firing, and at this stage, at least a part of the fourth subcomponent raw material is reacted to make the composition raw material. After that, a predetermined amount of the raw material, which is insufficient with respect to the final composition, is post-added and adjusted to the final composition to obtain a dielectric ceramic composition raw material. By firing the raw material prepared in this manner, R of the fourth subcomponent raw material is more likely to be evenly distributed in the grain boundaries in the fired dielectric ceramic composition, whereby the resulting dielectric is obtained. The accelerated life of insulation resistance of the porcelain composition is further improved.

Examples of the compound that becomes an oxide by firing include carbonate, nitrate, oxalate, and organometallic compound. Of course, an oxide and a compound that becomes an oxide by firing may be used together. The content of each compound in the raw material of the dielectric ceramic composition may be determined so as to be the above-mentioned composition of the dielectric ceramic composition after firing. The particle size of the dielectric ceramic composition powder in the state before being made into a paint is
Usually, the average particle size is about 0.0005 to 5 μm.

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

The organic vehicle is a binder dissolved in an organic solvent, and the binder used in the organic vehicle is not particularly limited and may be appropriately selected from various ordinary binders such as ethyl cellulose and polyvinyl butyral. The organic solvent used at this time is also not particularly limited, and may be appropriately selected from organic solvents such as terpineol, butyl carbitol, acetone, and toluene according to the printing method, the sheet method, or the like.

The water-soluble paint is a water-soluble binder, dispersant or the like dissolved in water, and the water-soluble binder is not particularly limited, and includes polyvinyl alcohol, cellulose, water-soluble acrylic resin, emulsion and the like. Can be selected as appropriate.

Internal Electrode Paste, External Electrode Paste The internal electrode paste is a conductive material made of the above-mentioned various conductive metals or alloys, or various oxides, organometallic compounds, resinates, etc. which become the above-mentioned conductive material after firing. It is prepared by kneading the above-mentioned organic vehicle. The external electrode paste is also prepared in the same manner as this internal electrode paste.

The content of the organic vehicle in each of the above-mentioned pastes is not particularly limited, and may be a normal content, for example, about 1 to 5% by weight of the binder and about 10 to 50% by weight of the solvent. In addition, each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators and the like, if necessary.

When the printing method is used, the dielectric paste and the internal electrode paste are laminated and printed on a substrate such as polyethylene terephthalate, cut into a predetermined shape and then peeled from the substrate to obtain a green chip. On the other hand, when the sheet method is used, a green sheet is formed using a dielectric paste, an internal electrode paste is printed on the green sheet, and then these are laminated to form a green chip.

Next, this green chip is subjected to binder removal processing and firing.

Binder removal treatment The binder removal treatment may be performed under normal conditions. Particularly when a base metal such as Ni or Ni alloy is used as the conductive material of the internal electrode layers, the temperature rising rate is 5 in an air atmosphere. ~ 3
00 ° C / hour, more preferably 10 to 100 ° C / hour,
Holding temperature is 180 to 400 ° C, more preferably 200 to
The temperature is maintained at 300 ° C. for 0.5 to 24 hours, more preferably 5 to 20 hours.

Firing The firing atmosphere of the green chip may be appropriately determined according to the type of conductive material in the internal electrode layer paste, but when a base metal such as Ni or Ni alloy is used as the conductive material,
The oxygen partial pressure in the firing atmosphere is preferably 10 ⁻¹⁰ to 10
⁻³ Pa, and more preferably 10 ^{−10 to} 6 × 10
^-5 Pa. If the oxygen partial pressure during firing is too low, the conductive material of the internal electrodes may abnormally sinter and break, and if the oxygen partial pressure is too high, the internal electrodes may be oxidized.
In particular, by adjusting the oxygen partial pressure to 10 ^{−10 to} 6 × 10 ⁻⁵ Pa and performing firing, it has excellent capacity-temperature characteristics, and further, the accelerated life of insulation resistance is improved, and the obtained multilayer ceramic capacitor is obtained. The reliability of 1 can be improved.

The holding temperature for firing is 1000 to 1400.
C., more preferably 1200 to 1380.degree. This is because if the holding temperature is too low, the densification becomes insufficient, and if the holding temperature is too high, the capacity-temperature characteristic deteriorates due to electrode breakage due to abnormal sintering of the internal electrode or diffusion of the internal electrode material.

Other firing conditions include a heating rate of 50 to 500 ° C./hour, more preferably 200 to 300.
C./hour, the temperature holding time is 0.5 to 8 hours, more preferably 1 to 3 hours, the cooling rate is 50 to 500.degree. C./hour, more preferably 200 to 300.degree. C./hour, and the firing atmosphere is a reducing atmosphere. It is desirable that the mixed gas of nitrogen gas and hydrogen gas be used as the atmosphere gas.

When firing in a reducing atmosphere, it is desirable to anneal (heat treat) the sintered body of the capacitor chip.

Annealing (heat treatment) Annealing is a process for re-oxidizing the dielectric layer, which can increase the insulation resistance. The oxygen partial pressure in the annealing atmosphere is preferably 10 ⁻⁴ Pa or more, more preferably 10 ⁻¹ to 10 Pa. If the oxygen partial pressure is too low, reoxidation of the dielectric layer 2 becomes difficult, and if the oxygen partial pressure is too high, the internal electrode layer 3 may be oxidized.

The holding temperature at the time of annealing is 1100 ° C. or lower, and more preferably 500 to 1100 ° C. If the holding temperature is too low, the reoxidation of the dielectric layer will be insufficient, the insulation resistance will be deteriorated, and the accelerated life will be shortened. Further, if the holding temperature is too high, not only the internal electrode is oxidized to reduce the capacity but also reacts with the dielectric substrate, which deteriorates the capacity-temperature characteristic, insulation resistance and its accelerated life. It should be noted that the annealing may be composed of only the temperature raising process and the temperature lowering process. In this case the temperature hold time is zero,
The holding temperature is synonymous with the maximum temperature.

As other annealing conditions, the temperature holding time is 0 to 20 hours, more preferably 6 to 10 hours,
The cooling rate is 50 to 500 ° C./hour, more preferably 10
It is desirable to use 0 to 300 ° C./hour, and use, for example, a humidified nitrogen gas as the annealing atmosphere gas.

As in the case of the above-described firing, a wetter or the like can be used to humidify the nitrogen gas or the mixed gas in the binder removal processing and the annealing step, and the water temperature in this case is 5 to 75. It is desirable to set the temperature to ° C.

The binder removal processing, firing and annealing may be performed continuously or independently of each other. When performing these continuously, the atmosphere is changed without cooling after the binder removal treatment, the temperature is raised to the holding temperature at the time of firing, and firing is performed, followed by cooling and the holding temperature of annealing. It is more preferable to change the atmosphere and perform the annealing treatment when the temperature reaches. On the other hand, when performing these independently, regarding firing, after raising the temperature to the holding temperature during the binder removal treatment in a nitrogen gas or humidified nitrogen gas atmosphere, the atmosphere can be changed and the temperature can be further continued. After cooling to the annealing holding temperature, it is preferable to change the atmosphere to nitrogen gas or a humidified nitrogen gas atmosphere again and continue cooling. Regarding annealing, the atmosphere may be changed after the temperature is raised to the holding temperature in a nitrogen gas atmosphere, or a wet nitrogen gas atmosphere may be used for all the annealing steps.

The capacitor fired body obtained as described above is subjected to end face polishing by, for example, barrel polishing or sandblasting, and the external electrode paste is printed or transferred and fired to form the external electrode 4. The firing conditions of the external electrode paste are preferably, for example, about 10 minutes to 1 hour at 600 to 800 ° C. in a mixed gas of humidified nitrogen gas and hydrogen gas. Then, if necessary, a coating layer (pad layer) is formed on the surface of the external electrode 4 by plating or the like.

The monolithic ceramic capacitor 1 of the present embodiment manufactured in this manner has excellent capacitance-temperature characteristics, the accelerated life of the insulation resistance is improved, and the reliability is improved.

The monolithic ceramic capacitor 1 thus manufactured is mounted on a printed board by soldering or the like and used in various electronic devices.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention. Of course.

For example, the dielectric ceramic composition obtained by the manufacturing method according to the present invention is not only used for a laminated ceramic capacitor, but may be used for other electronic parts in which a dielectric layer is formed. .

[0077]

EXAMPLES Next, the present invention will be described in more detail with reference to examples in which the embodiments of the present invention are more specified. However,
The invention is not limited to only these examples.

Example 1 In this example, a sample of a laminated ceramic capacitor was prepared by the following procedure. First, the following pastes were prepared.

Dielectric Layer Paste First, as a starting material for producing a dielectric material, a main component material (SrCO 3) having an average particle diameter of 0.1 to 1 μm is used.
₃ , CaCO ₃ , TiO ₂ ) and first to fourth subcomponent raw materials were prepared. In this embodiment, carbonate (second subcomponent: MnCO ₃ ) is used as a raw material of MnO, and oxides (first subcomponent: V ₂ O ₅ and third subcomponent: S are used as other raw materials.
iO ₂ + CaO, fourth subcomponent: Y ₂ O ₃ ) was used.

Next, the main component raw materials (SrCO ₃ , CaC) were weighed in predetermined amounts so as to have m'shown in Tables 1 to 4.
O ₃ and TiO ₂ ) and a predetermined amount of Y ₂ O ₃ were mixed and dried to obtain a pre-calcination powder. The addition amount of Y ₂ O ₃ shown in Tables 1 to 4 is the number of moles in terms of Y and is the number of moles with respect to 100 moles of the final composition of the main component.

Next, the material obtained by calcining the pre-calcined powder was pulverized with an alumina roll to obtain calcined powder (composition raw material). The temperature increase rate of calcination is 300 ° C
/ Hr, the holding temperature was 1100 ° C, and the temperature holding time was 2 hours in the air atmosphere.

Next, with respect to this calcined powder, V
_TwoO₅, MnCO_Three, (SiO _Two+ CaO)
And Y_TwoO_ThreeOf SrCO_Three,
CaCO_ThreeAnd TiO_TwoAdd a predetermined amount of {(S
r_0.64Ca_0.36) O} _m・ TiO_Two(Main character
Min) + V_TwoO₅(First subcomponent) + MnCO_Three(No.
2 subcomponents) + (SiO_Two+ CaO) (3rd subcomponent) +
Y_TwoO_ThreeIn the (fourth accessory component), the composition after firing is
Weigh it so that the compounding ratio shown in each sample in Tables 1 to 4 is obtained.
It was After that, each of them is made by ball mill at 16:00.
Dielectric porcelain composition with final composition after wet mixing and drying
I got the raw material.

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

Internal Electrode Layer Paste Next, Ni particles 100 having an average particle size of 0.2 to 0.8 μm are prepared.
By weight, 40 parts by weight of an organic vehicle (8 parts by weight of ethyl cellulose dissolved in 92 parts by weight of butyl carbitol) and 10 parts by weight of butyl carbitol are kneaded into a paste to form an internal electrode layer. I got a paste.

External electrode paste Next, 100 parts by weight of Cu particles having an average particle diameter of 0.5 μm, 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 butyl carbitol. 7 parts by weight was kneaded into a paste to obtain an external electrode paste.

Preparation of Green Chip Next, a 6 μm-thick green sheet was formed on a PET film using the above-mentioned dielectric layer paste, and the internal electrode layer paste was printed on the green sheet. The sheet was peeled off.

Then, these green sheets and a protective green sheet (without printing the internal electrode layer paste) were laminated and pressure-bonded to obtain a green chip. The number of laminated sheets having internal electrodes was four.

Next, the green chip is cut into a predetermined size, binder removal processing, firing and annealing (heat treatment).
The binder removal treatment was performed under conditions of a temperature rising time of 15 ° C./hour, a holding temperature of 280 ° C., a holding time of 8 hours, and an air atmosphere. Further, the firing was performed at a temperature rising rate of 200 ° C./hour, a holding temperature of 1200 to 1380 ° C., a holding time of 2 hours, a cooling rate of 300 ° C./hour, and a humidified N ₂ + H ₂ mixed gas atmosphere (oxygen partial pressure was measured in Sample 4, 4-1,4-2,5,5-
1, 19, 19-1 to 19-13 is 1 × 10 ⁻⁶ Pa,
Other samples were tested under the condition of 5 × 10 ⁻⁶ Pa). The annealing was performed under conditions of a holding temperature of 900 ° C., a temperature holding time of 9 hours, a cooling rate of 300 ° C./hour, and a humidified N ₂ gas atmosphere (oxygen partial pressure is 3.54 × 10 ⁻² Pa). In addition, for the humidification of the atmosphere gas at the time of firing and annealing,
A wetter having a water temperature of 35 ° C. was used.

Next, after polishing the end surface of the laminated ceramic fired body by sandblasting, the external electrode paste was transferred to the end surface and fired at 800 ° C. for 10 minutes in a humidified N ₂ + H ₂ atmosphere to external electrode. To form
A sample of the monolithic ceramic capacitor 1 having the structure shown in FIG. 1 was obtained.

The size of each sample thus obtained was 3.2 mm × 1.6 mm × 0.6 mm, the number of dielectric layers sandwiched by the internal electrode layers was 4, and the thickness thereof was 4 μm.
m, and the thickness of the internal electrode layer was 1.5 μm. The following characteristics of each sample were evaluated.

With respect to a sample of a dielectric constant (εr) and an insulation resistance (IR) capacitor, a digital LCR meter (4274A manufactured by YHP) at a reference temperature of 25 ° C., a frequency of 1 kHz and an input signal level (measurement voltage) of 1 Vrms The capacitance was measured under the conditions. Then, the relative permittivity (no unit) was calculated from the obtained capacitance, the electrode size of the capacitor sample, and the distance between the electrodes. Then, using an insulation resistance meter (R8340A manufactured by Advantest Corporation), DC50V was applied to the capacitor sample at 25 ° C. for 60 seconds to measure the insulation resistance IR, and the measured value and the electrode area and thickness of the capacitor sample were measured. Then, the specific resistance ρ (unit: Ωcm) was calculated. The results are shown in Tables 1 to 4. As an evaluation, the relative permittivity εr is an important characteristic for producing a small-sized capacitor having a high permittivity, and a value of 180 or more, and more preferably 200 or more is considered good. A specific resistance value of 1 × 10 ¹² Ωcm or more was considered good. The value of relative permittivity εr is the number of capacitor samples n = 10
It was calculated from the average value of the values measured using the individual pieces. The value of the specific resistance ρ was the average value of the specific resistances of 10 non-defective products.

Temperature Characteristics of Capacitance Using an LCR meter for a capacitor sample,
When the capacitance at a voltage of 1 kHz and 1 V is measured and the reference temperature is 20 ° C., the capacitance change rate with respect to temperature is −2000 to 0 ppm / ° C. within a temperature range of 20 to 85 ° C.
It was examined whether or not was satisfied, and when it was satisfied, it was evaluated as ◯, and when not satisfied, it was evaluated as x. The results are shown in Tables 1 to 4.

High temperature load life (accelerated life of insulation resistance) The high temperature load life was measured by holding a DC voltage of 8 V / μm at 200 ° C. on a capacitor sample. This high-temperature load life was evaluated by measuring the average life time of 10 capacitor samples (dielectric layer thickness 4 μm). The results are shown in Table 1.
~ Shown in Table 4. As an evaluation, the high temperature load life is particularly important when thinning the dielectric layer, and the time from the start of application until the resistance drops by one digit is defined as the life.

[0094]

[Table 1]

[0095]

[Table 2]

[0096]

[Table 3]

[0097]

[Table 4]

In Tables 1 to 4, the number of moles of the main additive after addition and the number of moles of the first to fourth subcomponents are ratios with respect to the final composition of 100 moles. Further Table 1
In the numerical value of the specific resistance (ρ) in Table 4, “mE +
“N” means “m × 10 ^{+ n} ”.

From the results shown in Table 1, addition of the fourth subcomponent was confirmed.
With regard to the timing of addition, the following can be confirmed. Samples 1-2
Is {(Sr_0.64Ca_0.36) O}_{m '}
・ TiO_TwoWhen preparing (main ingredient material), that is, the main ingredient
Y before calcination of raw materials_TwoO_Three (4th sub ingredient material) added
Then, the fourth sub ingredient material is made to react in advance with the main ingredient material.
After obtaining the composition raw material_TwoO₅, MnCO_ThreeOh
And (SiO_Two+ CaO) (first to third subcomponent raw materials)
Is added for firing. On the other hand, in sample 3,
Is after preparing the main ingredient materials, that is, calcination of the main ingredient materials
Later, the fourth sub-component raw material is added together with the first to third sub-component raw materials.
In addition, firing is performed. To compare sample 1 and sample 3
Then, as in Sample 3, the fourth subcomponent raw material
When added after baking, high temperature load life (insulation resistance accelerated life)
Life is insufficient. On the other hand, as in sample 1, the fourth
Preliminary reaction by adding auxiliary ingredient materials before calcination of the main ingredient materials
By doing so, a sufficient dielectric constant and insulation resistance (specific resistance)
And is not reduced even when fired in a reducing atmosphere.
Nickel, which is the internal electrode material, does not oxidize and is resistant to reduction.
It can be confirmed that an excellent dielectric porcelain composition was obtained.
It was In addition, it has excellent capacity-temperature characteristics and high temperature load.
Life (accelerated life of insulation resistance) is about 3 times that of sample 3.
It was confirmed that it can be improved every time. Between sample 1 and sample 2
In comparison, the final m of the main component is m ′ with respect to the raw material m ′.
In Sample 2 with <m, Sample 1 with final m = raw material m ′
About 1.5 times more than that (By the way, for sample 3
About 5 times), high temperature load life (acceleration life of insulation resistance)
It was confirmed that the life can be improved.

From the results shown in Table 2, the final m of the main component
Regarding the value, the following can be confirmed. M as in sample 4
In the case of = 0.94, even if the fourth sub ingredient material was reacted with the main ingredient material in advance, the dielectric was reduced by firing in a reducing atmosphere, and sufficient insulation resistance could not be obtained. Further, when m = 1.08 as in Sample 7, a dense sintered body can be obtained even if the fourth subcomponent raw material is preliminarily reacted with the main component raw material or is fired at 1380 ° C. (high temperature). I couldn't do it. On the other hand, in comparison between sample 5 and sample 5-1, a raw material obtained by previously reacting the fourth subcomponent raw material with the main component raw material is used, even if m = 0.995 as in sample 5 which is relatively high. As a result, Y or Y ₂ O ₃ was uniformly distributed in the grains, and as a result, the high temperature load life was about 1.
It has improved about 5 times. In the comparison between sample 6 and sample 6-1, even if the sample 6 is relatively high as m = 1.005, by using the raw material obtained by previously reacting the fourth subcomponent raw material with the main component raw material, Y or Y ₂ O _{3 in}
Was evenly distributed, and the high temperature load life was improved to about 4 times that of Sample 6-1. In comparison between sample 2 and sample 2-1, even if m = 1.02, which is relatively high as in sample 6, by using a raw material obtained by previously reacting the fourth subcomponent raw material with the main raw material, In addition, the high temperature load life was improved to about 5 times that of Sample 2-1.

In Sample 5 and Sample 5-1, the fourth
Although the timing of addition of the subcomponent raw material is different, the main component raw material m '= 0.985 in each case, and the final main component m
= 0.995. In each of Sample 6 and Sample 6-1, the raw material of the main component is m ′ = 0.985, but the final m of the main component is 1.015. Sample 2 and Sample 2-1
In each case, the raw material of the main component is m ′ = 0.985, but the final m of the main component is 1.02. That is, (Sample 2 and Sample 2-1), (Sample 6 and Sample 6-
In the order of 1) and (Sample 5 and Sample 5-1), the final m value of the main component is larger. Due to this difference, the sample 5 has a high temperature load life improved by about 1.5 times that of the sample 5-1, but the sample 6 has a high temperature load life of about 3 times that of the sample 6-1. Improved, in sample 2, sample 2
The high temperature load life is improved about 5 times compared to -1. From this, even in the samples (Sample 5, Sample 6 and Sample 2) in which the fourth sub ingredient material was added before the calcination of the main ingredient material and preliminarily reacted, the larger the final m value of the main ingredient, the longer the life. It was also confirmed that the effect of the improvement was remarkable.

In comparison between sample 4-1 and sample 4-2, the fourth subcomponent raw material was previously reacted with the main component raw material even if sample 4-2 had a relatively low m = 0.985. By using the above-mentioned raw material, Y or Y ₂ O is contained in the grains.
As a result of ₃ being distributed more uniformly, the high temperature load life was improved about 3 times or more as compared with Sample 4-1. From this, even if the final m of the main component is relatively low, it is better to use the raw material obtained by previously reacting the fourth subcomponent raw material with the main component raw material.
It was confirmed that it was effective in improving the high temperature load life.

From the results shown in Table 3, it was confirmed that the amount of the fourth subcomponent material added was as follows. When Y was not added at all as in Sample 8 and the amount of Y added was 2 mol as in Sample 13, no improvement in high temperature load life (accelerated life of insulation resistance) was observed. On the other hand, in the samples 2 to 6 containing the fourth subcomponent in a predetermined amount, m =
Even if it is relatively high as 1.02, it has a sufficient relative dielectric constant and insulation resistance (specific resistance), is not reduced even by firing in a reducing atmosphere, and nickel, which is an internal electrode material, is not oxidized. A dielectric ceramic composition having excellent reduction resistance was obtained. In addition, the capacity-temperature characteristics are excellent, and the high temperature load life (accelerated life of insulation resistance) is also improved.

From the results shown in Table 4, the following can be confirmed for the raw material m'value of the main component. In the case of m ′ = 0.9 as in Sample 14, even if the fourth subcomponent material was reacted with the main component material in advance, the dielectric was reduced by firing in a reducing atmosphere and sufficient insulation resistance was obtained. There wasn't.
When m ′ = 1.08 as in Sample 18, the effect of improving the high temperature load life was not observed even when the fourth subcomponent raw material was preliminarily reacted with the main component raw material. Sample 15-
17 and Sample 1, the final main component m = 1.
02, but the raw material m'value of the main component is Sample 1, Sample 1
7, the sample 16 and the sample 15 become smaller in this order. On the other hand, the high temperature load life time was
7, sample 16 and sample 15 are increasing in this order. From this, even in the sample in which the fourth sub ingredient material was added before the calcination of the main ingredient material and reacted in advance, the smaller the raw material m'value of the main ingredient, that is, the larger the difference from the final m value, It was also confirmed that the life time improved.

Example 2 Number of moles of first subcomponent (converted to V) = 0.2 moles, number of moles of second subcomponent (converted to Mn) = 0.37 moles, number of moles of third subcomponent = (2 0.5 + 2.5) mol, except for the fourth
The kind of R as a sub-component was changed as shown in Table 5, and 0.07 mol of the rare earth elements in the oxide was added to the pre-calcined powder, and calcined. The annealing temperature was 1100 ° C. and the holding time was 3 hours. In this way, a plurality of capacitor samples were prepared, and the defective occurrence rate of the initial insulation resistance (IR) of these samples was calculated. The results are shown in Table 5.

[0106]

[Table 5]

From the results shown in Table 5, Y, Sc, C
When oxides of e, Dy, Ho, Er, Tm, Yb and Lu were added (Sample 19 to Sample 19-8), T
Compared with the case where the oxides of b, Gd, Eu, Sm, and La were added (Samples 19-9 to 19-13), the non-defective rate of the initial insulation resistance (IR) was improved, that is, thinning (interlayer It was confirmed that the initial IR defect rate in the case of 4 μm) can be significantly reduced.

[0108]

As described above, according to the present invention, a dielectric material having excellent reduction resistance during firing, excellent capacitance-temperature characteristics after firing, and capable of improving the accelerated life of insulation resistance. It is possible to provide a method for producing a porcelain composition and a method for producing an electronic component such as a chip capacitor having improved reliability.

[Brief description of drawings]

FIG. 1 is a sectional view of a monolithic ceramic capacitor according to an embodiment of the present invention.

[Explanation of symbols] 1. Multilayer ceramic capacitor 10 ... Capacitor element body 2 ... Dielectric layer 3 ... Internal electrode layer 4 ... External electrode

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI H01G 4/12 418 H01G 4/12 418 (72) Inventor Mikio Takahashi 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (56) References JP-A-9-77555 (JP, A) JP-A-3-97669 (JP, A) JP-A-7-211138 (JP, A) JP-A-8-301657 (JP, A) JP-A-8-301658 (JP, A) JP-A-2001-247364 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C04B 35/42-35/50 CA (STN) REGISTRY (STN)

Claims (7)

(57) [Claims] 1. A composition formula {(Sr _1-x Ca _x ) O}
_m · (Ti _1-y Zr _y ) O ₂ , the molar ratio m in the composition formula is 0.94 <m <1.08, and the symbol x is 0 ≦ x ≦ 1.00. The symbol y is 0 ≦ y ≦ 0.
20 and the oxide of R (where R is Sc, Y, Ce, Pr, P
m, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb
And at least one selected from Lu)
A method for producing a dielectric porcelain composition having a subcomponent, wherein the dielectric porcelain composition is prepared by using a composition raw material obtained by previously reacting at least a part of a fourth subcomponent raw material with a main component raw material. A method for producing a dielectric ceramic composition, which comprises producing an article. 2. The dielectric according to claim 1, wherein the oxide of R contained in the fourth subcomponent is at least one oxide of Sc, Y, Ce, Dy, Ho, Er, Tm, Yb and Lu. A method for producing a body porcelain composition. 3. With respect to 100 mol of the main component raw material,
3. The method for producing a dielectric ceramic composition according to claim 1, wherein 0.04 mol or more and less than 2 mol of the fourth subcomponent raw material in the oxide is preliminarily reacted. 4. A composition formula {(Sr _1-x Ca _x ) O}
_m · (Ti _1-y Zr _y ) O ₂ , the molar ratio m in the composition formula is 0.94 <m <1.08, and the symbol x is 0 ≦ x ≦ 1.00. The symbol y is 0 ≦ y ≦ 0.
20 and the oxide of R (where R is Sc, Y, Ce, Pr, P
m, Eu , Gd, Tb, Dy, Ho, Er, Tm, Yb
And at least one selected from Lu)
A method for producing a dielectric ceramic composition having a subcomponent, comprising: a composition formula {(Sr _1-x Ca _x ) O} _{m ′} · (Ti
_1-y Zr _y ) O ₂ and the molar ratio m ′ in the composition formula is m ′ < m with respect to the molar ratio m of the final composition. A method for producing a dielectric ceramic composition, characterized in that the dielectric ceramic composition is produced using a composition raw material obtained by preliminarily reacting at least a part of the raw material. 5. The dielectric porcelain composition according to claim 4, wherein the dielectric porcelain composition is produced by adding a substance containing at least one element of Sr and Ca to the composition raw material and then firing the mixture. Production method. 6. A composition formula {(Sr _1-x Ca _x ) O}
_m · (Ti _1-y Zr _y ) O ₂ , the molar ratio m in the composition formula is 0.94 <m <1.08, and the symbol x is 0 ≦ x ≦ 1.00. The symbol y is 0 ≦ y ≦ 0.
20 and the oxide of R (where R is Sc, Y, Ce, Pr, P
m, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb
And at least one selected from Lu)
A method of manufacturing an electronic component having a dielectric layer composed of a dielectric porcelain composition having a subcomponent, wherein at least a part of the fourth subcomponent raw material is previously reacted with the main component raw material. A method for manufacturing an electronic component, which comprises manufacturing the dielectric ceramic composition using a composition raw material. 7. The electron according to claim 6, wherein the oxide of R contained in the fourth subcomponent is at least one oxide of Sc, Y, Ce, Dy, Ho, Er, Tm, Yb and Lu. Manufacturing method of parts.