JP2002080279A - Method of manufacturing dielectric ceramic composition and method of manufacturing electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing electronic component heightened in reliability such as a chip capacitor excellent in reduction resistance at firing having good capacitance temperature characteristics after the firing capable of improving acceleration life of insulating resistance. SOLUTION: The manufacturing method of the electronic parts having dielectric layer constituted of dielectric ceramic composition having main ingredient represented by a formula (Sr1-xCax)O}m.(Ti1-yZry)O2 in which mole ratio m is 0.995<=m<1.08, x is 0<=x<=1.00, y is 0<=y<=0.20 and a fourth sub ingredient containing oxide of R (R is at least one kind selected from among Sc, Y, La, Ce, Pr, Nb, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu). The method of manufacturing the dielectric ceramic composition is characterized by using raw material of composition which is previously reacted with raw material of main ingredient and at least a part of raw material of the fourth sub ingredient.

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 a dielectric layer of a multilayer ceramic capacitor, and an electronic component using the dielectric ceramic composition as a dielectric layer. About the method.

[0002]

2. Description of the Related Art A multilayer ceramic capacitor, which is an example of an electronic component, is formed by printing a conductive paste on a green sheet made of a predetermined dielectric ceramic composition, and laminating a plurality of green sheets printed with the conductive paste. The green sheet and the internal electrode are integrally fired and formed.

A conventional dielectric porcelain composition is reduced when fired 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 multilayer ceramic capacitor, it has been necessary to perform firing in an oxidizing atmosphere having a high oxygen partial pressure. Accordingly, as an internal electrode material that is fired simultaneously with the dielectric ceramic composition, an expensive noble metal that does not melt at the temperature at which the dielectric ceramic composition sinters and is not oxidized even when fired in an oxidizing atmosphere. (For example, palladium or platinum) must be used, which has been a great obstacle to reducing the price of the manufactured multilayer ceramic capacitor.

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

Hitherto, various proposals have been made as dielectric ceramic compositions in which a base metal can be used as a material for an internal electrode.

For example, Japanese Unexamined Patent Publication No. 63-224108
In the report, (Sr_1-xCa_x) _m(Ti_1-y
Zr_y) O₃Dielectric oxide of composition shown by
0.30 ≦ x ≦ 0.50, 0.03 ≦ y ≦ 0.2
0, 0.95 ≦ m ≦ 1.08) as a main component.
Mn as MnO
₂0.01 to 2.00 parts by weight in conversion, SiO₂To
0.10 to 4.00 parts by weight of the dielectric porcelain composition
It has been disclosed.

Japanese Patent Application Laid-Open No. 63-224109 discloses a dielectric porcelain composition containing 0.01 to 1.00 parts by weight of ZnO in addition to the above-mentioned main component, in addition to the above-mentioned Mn and SiO _2. It has been disclosed.

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

Further, Japanese Patent Publication No. 62-24388
In the report, (MeO)_kTiO₂Dielectric of composition shown by
Body oxides (where Me is Sr, Ca and Sr + Ca
A metal selected from the group consisting of 1.00 and 1.04).
And a glass component with respect to 100 parts by weight of the main component.
As Li₂O, M (where M is BaO, CaO
At least one metal oxide selected from and SrO
Product) and SiO₂ Is used at a predetermined molar ratio.
A dielectric porcelain composition containing from 2 to 10.0 parts by weight is disclosed.
It is.

[0010]

However, when the dielectric ceramic compositions described in these publications are manufactured by an ordinary method, the accelerated life of the insulation resistance after firing is insufficient in any case. When a multilayer ceramic capacitor having an internal electrode made of a base metal such as nickel is manufactured using a dielectric ceramic composition, there is a problem that the reliability of the obtained multilayer ceramic capacitor is reduced. In addition,
We have found that the molar ratio m is relatively low, ｛(Sr
_1-x Ca _x ) O｝ _m · (Ti _1-y Z
In r _y) composition system expressed by O _2, in order to enhance the accelerated lifetime of insulation resistance, it is proposed to add a rare earth component such as yttrium (Japanese Patent Application No. 2000-18
No. 7800). However, in the case of manufacturing by a usual method, it is difficult to extend the life even if a rare earth component is added, when the molar ratio m is relatively high in the range of 0.995 ≦ m <1.08.

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

[0012]

To achieve the above object, according to the Invention The production method of a dielectric ceramic composition according to the present invention, a composition formula _{{(Sr 1-x Ca x} ) O} m · (Ti
_1-y Zr _y) is represented by _{O 2,} the molar ratio m is 0.94 <m <1.08 in the composition formula, the symbol x is 0 ≦
a main component in which x ≦ 1.00 and the symbol y satisfies 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, at least one selected from Dy, Ho, Er, Tm, Yb, and Lu). The dielectric ceramic composition is manufactured using a composition raw material in which at least a part of the four subcomponent raw materials is reacted in advance.

[0013] The method for manufacturing an electronic component according to the present invention is characterized in that the composition
Equation ｛(Sr_1-xCa_x) O｝ _m・ (Ti
_1-yZr_y) O₂Represented by the formula in the above formula.
Is 0.94 <m <1.08, and the symbol x is 0 ≦
x ≦ 1.00, and the symbol y is 0 ≦ y ≦ 0.20
A main component and an 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
Having at least one of the following:
Electronic part having dielectric layer composed of dielectric ceramic composition
A method of manufacturing a product, wherein a fourth sub
Composition raw material in which at least a part of the component raw materials are reacted in advance
Using the above to produce the dielectric ceramic composition
And

By preliminarily reacting at least a part of the fourth subcomponent material with the main component material, it is considered that the distribution of the fourth subcomponent after the main firing 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 a part" means at least a part of the fourth subcomponent raw material corresponding to the total amount of the fourth subcomponent to be included in the final composition. However, it is preferable to react the entire amount of the fourth subcomponent to be included in the final composition.

Preferably, a composition raw material in which 0.04 mol or more and less than 2 mol, in terms of R in the oxide, of the fourth subcomponent raw material is previously reacted with 100 mol of the main component raw material is used. Used.

Preferably, the main component material has a composition formula {(Sr _1-x Ca _x ) O} _{m ′} · (Ti _1-y
Zr _y) is represented by _{O 2,} the molar ratio in the composition formula m '
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 Is added and then fired.

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

[0020]

[Function] Composition formula ｛(Sr_1-xCa_x) O｝_m・
(Ti_1-yZr_y) O₂ 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
If the composition is manufactured in the usual way, the insulation resistance
It is difficult to improve accelerated life (high temperature load life)
Have been clarified by the present inventors. That field
The cause is the grain boundary and triple point in the dielectric ceramic composition after firing.
Segregation of a large amount of R or R oxides in the fourth subcomponent raw material
Is not distributed uniformly in the grains.
You.

In the method for producing a dielectric porcelain composition according to the present invention, the dielectric porcelain composition is obtained by using a composition raw material in which at least a part of a fourth subcomponent raw material is previously reacted with a main component raw material. By the production of, the excellent resistance to reduction during firing, has excellent capacity temperature characteristics after firing, and furthermore, R or R of the fourth subcomponent material in the grain boundaries in the dielectric ceramic composition after firing Since the oxides of R are uniformly distributed, it is possible to manufacture a dielectric ceramic composition having an improved accelerated life of insulation resistance (for example, 200 ° C., 8 V DC / μm). In particular, the composition formula (Sr) having a molar ratio m ′ smaller than the molar ratio m after firing.
_1-x Ca _x ) O｝ _{m ′} · (Ti _1-y Z
r _y ) When the main component material represented by O ₂ is used, the fourth subcomponent material, R, is added to the fired dielectric ceramic composition.
Alternatively, the oxide of R is more likely to be distributed more uniformly, whereby the accelerated life of the insulation resistance of the obtained dielectric ceramic composition is further improved. 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 subcomponent material is not previously reacted with the main component material, the calcination after firing is not required. The present inventors have found that in the dielectric ceramic composition, the fourth subcomponent is almost uniformly distributed in the grains of the main component. However, even in such a range where the molar ratio m is relatively low, the fourth
By producing the dielectric porcelain composition using the composition raw material in which the sub-component raw materials are pre-reacted, the fourth sub-component raw material is not preliminarily reacted with the main raw material, that is, with respect to the main raw material. As a result, the fourth subcomponent is more likely to be more uniformly distributed in the grains of the main component as compared with the case where the raw material to which the fourth subcomponent raw material is added later is used. As a result, a further improvement in the accelerated life of the insulation resistance can be expected.

According to 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, an improved accelerated life of insulation resistance, and improved reliability.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments shown in the drawings. FIG. 1 is a sectional view of a multilayer ceramic capacitor according to one embodiment of the present invention. Before describing the method for producing the dielectric ceramic composition according to the present invention, first, a multilayer ceramic capacitor will be described.

[0024] As shown in multilayer ceramic capacitors Figure 1, a multilayer ceramic capacitor 1 as an electronic device according to an embodiment of the present invention, comprised of dielectric layers 2 and internal electrode layers 3 stacked alternately It has a capacitor element body 10.

A pair of external electrodes 4 are formed at both ends of the capacitor element body 10 so as to be 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 surfaces 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.

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,
Composition formula {(Sr _1-x Ca _x ) O} _m · (Ti
Having a principal component represented by _{1-y Zr y) O 2} .
At this time, the amount of oxygen (O) may slightly deviate 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 it is possible to arbitrarily shift the phase transition point of the crystal by changing x, that is, the Ca / Sr ratio. Therefore, the capacitance temperature coefficient and the relative permittivity can be arbitrarily controlled. When x is in the above range, the phase transition point of the crystal exists near room temperature, and the temperature characteristics of the 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 the relative dielectric constant is prevented. y is Z
represents the number of r atoms, but is harder to reduce than TiO ₂
Substitution of rO ₂ tends to further increase the reduction resistance. However, in the present invention, Zr does not necessarily have to be contained, and may contain only Ti.

In the above formula, the molar ratio m should be larger than 0.94, preferably 0.995 ≦ m <1.08. By setting m to be larger than 0.94, it is possible to prevent the semiconductor from being converted into a semiconductor during firing in a reducing atmosphere. In particular, when m is set to 0.995 or more, the oxygen partial pressure during firing can be further reduced. , The life is extended, and m is set to 1.08
By setting it to less than 1, a dense sintered body can be obtained without raising 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 (however, R
Are Sc, Y, La, Ce, Pr, Nd, Pm, Sm,
And at least one selected from the group consisting of Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu). This fourth subcomponent has the effect of improving the high-temperature load life (the accelerated life of the insulation resistance) and the initial insulation resistance (IR) when the dielectric is made thin (for example, about 4 μm).
It also has the effect of improving the defective rate. From the viewpoint of the improvement of the defective rate (the good rate of the initial IR is preferably 15% or more), Sc, Y, Ce, Dy, Ho, Er, Tm, and Yb
And at least one oxide of Lu. The molar ratio m of the main component is relatively high 0.9
Even in the range of 95 ≦ m <1.08, by adding a predetermined amount of the fourth subcomponent at a 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 greatly 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 later, the fourth subcomponent is added at the timing described later.
As compared with the case where no subcomponent is added, the accelerated life (high-temperature load life) of the insulation resistance of the dielectric layer 2 is improved.

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

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

The dielectric ceramic composition obtained by the method of the present invention for forming the dielectric layer 2 includes V, Nb,
A first subcomponent containing at least one selected from oxides of W, Ta and Mo and / or compounds that become these oxides after firing may be added in a predetermined amount. By adding the first subcomponent in a predetermined amount, low-temperature sintering can be performed without deteriorating the dielectric characteristics, and the accelerated life of the insulation resistance (high-temperature load life) can be improved even when the dielectric layer is thinned. . When the first subcomponent is added, the ratio of the first subcomponent to 100 mol of the main component is 0.01 mol ≦ first subcomponent <2 mol, preferably 0.1 mol, in terms of metal element in the oxide. 04 mol ≦ first subcomponent ≦
0.6 mol.

The dielectric porcelain composition further includes 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. You may. The second subcomponent has the effect of promoting sintering and the effect of improving the high-temperature load life, and reduces the initial insulation resistance (IR) failure rate when the dielectric layer 2 is thinned to, for example, about 4 μm. It also has the effect of lowering. When adding the second subcomponent,
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 the metal element in the oxide. It is.

Further, the dielectric ceramic composition includes SiO 2
₂, MO (where M is Ba, Ca, Sr and M
g), Li₂O
And B ₂O₃A number that includes at least one selected from
A prescribed amount of the three subcomponents may be added. This third by-product
The component acts mainly as a sintering aid. The third subcomponent
In the case of adding, based on 100 moles of the main component
The ratio of the third subcomponent is 0 mol <third in terms of oxide.
Subcomponent <15 mol, preferably 0.2 mol ≦ third subcomponent
≦ 6 mol.

Note that various conditions such as the number of 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 a material constituting the dielectric material or the internal electrode material,
An oxide of a material separately added, or an oxide of a material mixed as an impurity during the process is used as a component and is 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 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,
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 and the like, but is usually preferably 0.5 to 5 μm, particularly preferably about 1 to 2.5 μm.

External Electrode 4 The conductive material contained in the external electrode 4 is not particularly limited, but usually Cu or Cu alloy, Ni or Ni alloy or the like is used. Incidentally, Ag, Ag-Pd alloy or the like can of course be used. In this embodiment, inexpensive Ni, C
u and their alloys are used. The thickness of the external electrode may be appropriately determined according to the application and the like.
m is preferable.

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, this is manufactured by printing or transferring an external electrode and firing. Hereinafter, the manufacturing method will be specifically described. A paste for a dielectric layer, a paste for an internal electrode, and a paste for an external electrode are respectively manufactured.

The dielectric layer paste is prepared first the dielectric ceramic composition material included in the dielectric layer paste. In the present invention, the dielectric ceramic composition raw material includes a composition raw material obtained by previously reacting a fourth subcomponent raw material with a main component raw material. It is considered that the fourth subcomponent raw material is in a solid solution in the main component raw material of the composition raw material.

As the fourth subcomponent material, an oxide of R (where R is Sc, Y, La, Ce, Pr, Nd, P
m, Sm, Eu, Gd, Tb, Dy, Ho, Er, T
m, Yb, and Lu). From the viewpoint of improving the defect 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
｛(Sr_1-xCa_x) O｝_{m '}・ (Ti_1-y
Zr_y) O₂Is used. In addition, this implementation
In the embodiment, the molar ratio m ′ in the composition formula is determined by the composition formula ｛(S
r_1-xCa_x) O｝_m ・ (Ti_1-yZ
r_y) O₂The fired dielectric porcelain composition represented by
Less than the molar ratio m of the oxide in the composition formula
(M '<m). However, in the present invention, the raw material stage
The molar ratio m 'in the floor and the molar 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 smaller than the molar ratio m after firing.
In this case, the fired dielectric ceramic constituting the dielectric layer 2
Oxidation of R or R of the fourth subcomponent raw material in the grain boundary in the composition
Objects are easier to distribute more evenly,
The accelerated life of insulation resistance of the dielectric ceramic composition
Layer can be improved. The lower limit of the molar ratio m 'is based on the principle of preventing semiconductor conversion.
For this reason, preferably set to be greater than 0.9
And more preferably 0.92 ≦ m ′ ≦ 1.06, furthermore
0.92 ≦ m ′ ≦ 1.02, particularly preferably
0.94 ≦ m ′ ≦ 1.00.

The composition formula ｛(Sr_1-xCa
_x) O｝_{m '}・ (Ti_1-yZr _y) O₂In table
The main component materials used are not only the so-called solid phase method, but also the so-called liquid
It may be obtained by a phase method. The solid phase method
For example, SrCO₃, CaCO₃, TiO₂, Z
rO₂When using as starting materials
Raw materials are obtained by weighing, mixing, calcining, and pulverizing.
It is a method. The liquid phase synthesis methods include the oxalate method, water
Examples include a thermal synthesis method and a sol-gel method. In addition, a mole
Sr_tTiO₃And b moles of Ca_{t '}TiO₃
And c moles of Sr _{t ''}ZrO₃And d moles of Ca
_{t '''}ZrO₃To mix raw materials
, M ′ is m ′ = (at + bt ′ + ct ″ + d
t "") / (a + b + c + d)
You.

In order to react the fourth subcomponent raw material with such a main component raw material, when producing the main component raw material,
The starting material may be mixed with a fourth subcomponent material, and the composition material may be obtained by a solid phase method, a liquid phase method, or the like. Alternatively, the composition raw material may be obtained by adding the fourth subcomponent raw material thereto. In any case, the amount of R in the oxide 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, based on 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 material in such a range, the accelerated life of insulation resistance of the obtained dielectric ceramic composition can be improved.

Hereinafter, a method of obtaining a composition raw material by reacting the fourth subcomponent raw material when producing the main component raw material by the solid phase method will be described as an example.

First, SrCO ₃ , CaCO ₃ , TiO ₂ , ZrO ₂
A pre-calcining raw material is prepared by weighing a predetermined amount of a fourth sub-component raw material such as Y ₂ O _{3 in} addition to each main raw material such as Y ₂ O ₃ , mixing and drying.

Next, the prepared powder before calcining is calcined. The calcination conditions are not particularly limited, but are preferably performed under the following conditions. The heating rate is preferably 50 to
400 ° C./hour, more preferably 100 to 300 ° C./hour. The holding temperature is preferably between 500 and 1200
° C, more preferably 700 to 1100 ° C. The temperature holding time is preferably 0.5 to 6 hours, more preferably 1 to 3 hours. The treatment atmosphere may be any of air, nitrogen and a reducing atmosphere.

Next, the calcined calcined powder is coarsely pulverized by an alumina roll or the like, and then the composition formula {(Sr _1-x Ca _x ) O} _m · (Ti
_1-y Zr _y) is mixed with raw material powders to achieve _{O 2.} At this time, the first to third subcomponent raw materials may be added as necessary. However, the first to third subcomponent raw materials may be added before calcining. 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 material, a single oxide or a composite oxide of a compound of Mn and / or a compound which becomes a Mn oxide 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 one selected from i ₂ O and B ₂ O ₃
One is used.

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

Thereafter, this mixed powder is added, if necessary,
By mixing and drying with a ball mill or the like, 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 obtained by previously reacting at least a part of the fourth subcomponent raw material with the main component raw material is used.
By subjecting it to the calcination described below, the R in the fourth subcomponent material is added to the grain boundary portion and the triple point in the baked dielectric ceramic composition.
Alternatively, as a result of the oxide of R not being segregated and being uniformly distributed in the grains, the accelerated life of insulation resistance can be improved.

In particular, in the present 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 form the composition raw material. After that, a predetermined amount of raw material that is insufficient with respect to the final composition is post-added to adjust the final composition to obtain a dielectric ceramic composition raw material. By firing the raw material thus prepared, R of the fourth subcomponent raw material is more likely to be distributed more uniformly in the grain boundaries in the fired dielectric porcelain composition. The accelerated life of the insulation resistance of the porcelain composition is further improved.

Examples of the compound which becomes an oxide upon firing include carbonates, nitrates, oxalates, and organometallic compounds. Of course, an oxide and a compound which becomes an oxide by firing may be used in combination. The content of each compound in the raw material of the dielectric ceramic composition may be determined so as to have the above-described composition of the dielectric ceramic composition after firing. Before coating, the particle size of the dielectric ceramic composition powder is
Usually, the average particle size is about 0.0005 to 5 μm.

Next, this dielectric ceramic composition raw material 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 raw material and an organic vehicle, or may be an aqueous paint.

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 ordinary various binders such as ethyl cellulose and polyvinyl butyral. In addition, the organic solvent used at this time is not particularly limited, and may be appropriately selected from organic solvents such as terpineol, butyl carbitol, acetone, and toluene depending on a method such as a printing method or a sheet method.

The water-based paint is obtained by dissolving a water-soluble binder, a dispersant, and the like in water. The water-soluble binder is not particularly limited, and may be polyvinyl alcohol, cellulose, water-soluble acrylic resin, emulsion, or the like. May be selected as appropriate.

Internal electrode paste and external electrode paste The internal electrode paste is made of 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. And the above-mentioned organic vehicle. The external electrode paste is also prepared in the same manner as the internal electrode paste.

The content of the organic vehicle in each of the above-mentioned 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. Each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators, and the like, as necessary.

When the printing method is used, a dielectric chip and an internal electrode paste are laminated and printed on a substrate such as polyethylene terephthalate, cut into a predetermined shape, and then peeled off 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 thereon, and these are laminated to form a green chip.

Next, the green chip is subjected to binder removal treatment and firing.

The binder removal treatment may be performed under ordinary conditions. In particular, when a base metal such as Ni or a Ni alloy is used as the conductive material of the internal electrode layer, the temperature increase rate is set to 5 in an air atmosphere. ~ 3
00 ° C / hour, more preferably 10 to 100 ° C / hour,
The holding temperature is 180 to 400 ° C, more preferably 200 to 400 ° C.
The temperature is kept at 300 ° C. for 0.5 to 24 hours, more preferably 5 to 20 hours.

The firing atmosphere of the fired 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 oxygen partial pressure of the firing atmosphere is preferably 10 ⁻¹⁰ to 10
^-3 Pa, more preferably 10 ^{-10 to} 6 × 10
^-5 Pa. If the oxygen partial pressure at the time of firing is too low, the conductive material of the internal electrode will be abnormally sintered and will be interrupted. If the oxygen partial pressure is too high, the internal electrode may be oxidized.
In particular, by sintering by adjusting the oxygen partial pressure to 10 ^{−10 to} 6 × 10 ⁻⁵ Pa, the obtained multilayer ceramic capacitor has excellent capacity-temperature characteristics, and has an improved accelerated life of insulation resistance. 1 can be improved.

The holding temperature for firing is 1000 to 1400
° C, more preferably from 1200 to 1380 ° C. If the holding temperature is too low, the densification becomes insufficient, and if the holding temperature is too high, the capacitance-temperature characteristics deteriorate due to the interruption of the electrodes due to abnormal sintering of the internal electrodes or the 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.
° C / hour, the temperature holding time is 0.5-8 hours, more preferably 1-3 hours, the cooling rate is 50-500 ° C / hour, more preferably 200-300 ° C / hour, and the firing atmosphere is a reducing atmosphere. It is desirable to use, for example, a wet mixed gas of nitrogen gas and hydrogen gas as the atmosphere gas.

When firing in a reducing atmosphere, it is desirable to perform annealing (heat treatment) on the sintered body of the capacitor chip.

Annealing (Heat Treatment) Annealing is a process for reoxidizing the dielectric layer, and can increase the insulation resistance. The oxygen partial pressure of 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 less, more preferably 500 to 1100 ° C. If the holding temperature is too low, the reoxidation of the dielectric layer becomes insufficient, the insulation resistance is deteriorated, and the accelerated life is shortened. On the other hand, if the holding temperature is too high, not only is the internal electrode oxidized to lower the capacity, but also reacts with the dielectric substrate, which deteriorates the capacity temperature characteristic, insulation resistance and accelerated life thereof. Note that the annealing may be constituted by only the temperature raising step and the temperature lowering step. In this case, the temperature holding time is zero,
The holding temperature is synonymous with the maximum temperature.

Other annealing conditions include a temperature holding time of 0 to 20 hours, more preferably 6 to 10 hours,
The cooling rate is 50 to 500 ° C./hour, more preferably 10 to 500 ° C./hour.
The temperature is set to 0 to 300 ° C./hour, and as an atmosphere gas for annealing, for example, it is desirable to use a wetted nitrogen 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 treatment and the annealing step. It is desirable to be set to ° C.

The binder removal processing, firing and annealing may be performed continuously or independently of each other. In the case where these steps are continuously performed, the atmosphere is changed without cooling after the binder removal processing, the temperature is raised to the holding temperature at the time of firing, and firing is performed. When the temperature reaches the above, it is more preferable to change the atmosphere and perform the annealing treatment. On the other hand, when these are performed independently, it is necessary to raise the temperature in the nitrogen gas or humidified nitrogen gas atmosphere to the holding temperature at the time of the binder removal treatment, and then change the atmosphere and continue the temperature increase. Preferably, after cooling to the holding temperature for annealing, it is preferable to change to a nitrogen gas or humidified nitrogen gas atmosphere again and continue cooling. Further, regarding the annealing, the atmosphere may be changed after the temperature is raised to the holding temperature in the nitrogen gas atmosphere, or the entire annealing process may be performed in a humidified nitrogen gas atmosphere.

The end body 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 conditions for the external electrode paste are preferably, for example, about 10 minutes to 1 hour at 600 to 800 ° C. in a humidified mixed gas of 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 multilayer ceramic capacitor 1 of the present embodiment manufactured as described above has excellent capacitance-temperature characteristics, an improved accelerated life of insulation resistance, and improved reliability.

The multilayer ceramic capacitor 1 manufactured as described above is mounted on a printed circuit board by soldering or the like, and is used for various electronic devices.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments at all, and may be implemented in various modes without departing from the gist of the present invention. Of course.

For example, the dielectric porcelain composition obtained by the manufacturing method according to the present invention is not limited to being used only for multilayer ceramic capacitors, but may be used for other electronic parts on which a dielectric layer is formed. .

[0077]

Next, the present invention will be described in more detail by way of examples which embody the embodiments of the present invention. However,
The present invention is not limited to only these examples.

Example 1 In this example, a sample of a multilayer ceramic capacitor was manufactured in 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) having an average particle size of 0.1 to 1 μm was used.
₃ , CaCO ₃ , TiO ₂ ) and first to fourth subcomponent raw materials. In this embodiment, a carbonate (second sub-component: MnCO ₃ ) is used as a raw material of MnO, and an oxide (first sub-component: V ₂ O ₅ , third sub-component: S) is used as another raw material.
iO ₂ + CaO, fourth subcomponent: Y ₂ O ₃ ) was used.

Next, the main component raw materials (SrCO ₃ , CaC
O ₃ and TiO ₂ ) and a predetermined amount of Y ₂ O ₃ were mixed and dried to obtain a powder before calcining. The addition amount of Y ₂ O ₃ shown in Tables 1 to 4 is the number of moles in terms of Y and the number of moles based on 100 moles of the final composition of the main component.

Next, the material obtained by calcining the powder before calcining was pulverized with an alumina roll to obtain calcined powder (composition raw material). For calcination, the heating rate is 300 ° C.
/ Hour, holding temperature was 1100 ° C., and temperature holding time was 2 hours in an air atmosphere.

Next, with respect to the calcined powder,
₂O₅, MnCO₃, (SiO ₂+ CaO)
And Y₂O₃Is added in a predetermined amount, and SrCO₃,
CaCO₃And TiO₂Is added by a predetermined amount, and ｛(S
r_0.64Ca_0.36) O｝ _m・ TiO₂(Master
Min) + V₂O₅(First subcomponent) + MnCO₃(No.
2 subcomponents) + (SiO₂+ CaO) (third subcomponent) +
Y₂O₃In the (fourth subcomponent), the composition after firing is
Weigh so as to have the compounding ratio shown in each sample of Tables 1 to 4.
Was. After that, each of these was mixed at 16:00 with a ball mill.
After wet mixing and drying, the final dielectric ceramic composition
Raw material was obtained.

100 parts by weight of the dielectric ceramic composition raw material 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, thereby obtaining a dielectric layer paste.

Paste for Internal Electrode Layer Next, Ni particles 100 having an average particle size of 0.2 to 0.8 μm
Parts 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 with a three-roll mill to form a paste, which is used for an internal electrode layer. A paste was obtained.

External electrode paste Next, 100 parts by weight of Cu particles having an average particle size 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 and kneaded to obtain a paste for an external electrode.

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 an internal electrode layer paste was printed thereon. The sheet was peeled off.

Next, these green sheets and protective green sheets (without printing the internal electrode layer paste) were laminated and pressed to obtain a green chip. The number of stacked sheets having internal electrodes was four.

Next, the green chip is cut into a predetermined size, the binder is removed, baked, and annealed (heat treatment).
Was performed under the conditions of a heating time of 15 ° C./hour, a holding temperature of 280 ° C., a holding time of 8 hours, and an air atmosphere. The firing was performed at a heating 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 (the oxygen partial pressure was 4-1, 4-2, 5, 5-
1, 19, 19-1 to 19-13 are 1 × 10 ⁻⁶ Pa,
Other samples were performed under the conditions of 5 × 10 ⁻⁶ Pa). Annealing was performed under the 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). The humidification of the atmosphere gas during firing and annealing includes:
A wetter with a water temperature of 35 ° C. was used.

Next, after polishing the end face of the laminated ceramic fired body by sand blasting, the external electrode paste was transferred to the end face, and fired at 800 ° C. for 10 minutes in a humidified N ₂ + H ₂ atmosphere to be fired. To form
A sample of the multilayer ceramic capacitor 1 having the configuration 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 between the internal electrode layers was 4, and the thickness was 4 μm.
m, and the thickness of the internal electrode layer was 1.5 μm. The following characteristics were evaluated for each sample.

A sample of a dielectric constant (εr) and an insulation resistance (IR) capacitor was measured at a reference temperature of 25 ° C. using a digital LCR meter (4274A manufactured by YHP) at a frequency of 1 kHz and an input signal level (measurement voltage) of 1 Vrms. Under the conditions, the capacitance was measured. Then, a relative dielectric constant (no unit) was calculated from the obtained capacitance, the electrode dimensions of the capacitor sample, and the distance between the electrodes. Thereafter, the insulation resistance IR after applying DC 50 V to the capacitor sample at 25 ° C. for 60 seconds at 25 ° C. was measured using an insulation resistance meter (R8340A manufactured by Advantest), and the measured value, the electrode area and the thickness of the capacitor sample were measured. , The specific resistance ρ (unit: Ωcm) was obtained by calculation. The results are shown in Tables 1 to 4. As an evaluation, the relative dielectric constant εr is an important characteristic for producing a small-sized and high-dielectric-constant capacitor, and is set to 180 or more, more preferably 200 or more. A specific resistance value of 1 × 10 ¹² Ωcm or more was determined to be good. The value of the relative permittivity εr is determined by the number of capacitor samples n = 10
It was determined from the average value of the values measured using the test pieces. The value of the specific resistance ρ was an average value of the specific resistances of 10 good products.

The temperature characteristic of the capacitance was measured using a LCR meter for a sample of the capacitor.
The capacitance at a voltage of 1 kHz and 1 V is measured, and when the reference temperature is set to 20 ° C., the capacitance change rate with respect to the temperature is −2000 to 0 ppm / ° C. within a temperature range of 20 to 85 ° C.
Was checked to determine whether or not the condition was satisfied, and the case where the condition was satisfied was evaluated as ○, and the case where the condition was not satisfied was evaluated as ×. The results are shown in Tables 1 to 4.

High-Temperature Load Life (Accelerated Life of Insulation Resistance ) The high-temperature load life of a capacitor sample was measured by maintaining a DC voltage of 8 V / μm at 200 ° C. This high-temperature load life was evaluated for ten capacitor samples (dielectric layer thickness 4 μm) and the average life time was measured. Table 1 shows the results
To Table 4 below. As an evaluation, the high-temperature load life is particularly important when the thickness of the dielectric layer is reduced, 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]

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

From the results shown in Table 1, the addition of the fourth subcomponent was
Regarding the timing of addition, the following was confirmed. In samples 1-2
Is ｛(Sr_0.64Ca_0.36) O｝_{m '}
・ TiO₂At the time of mixing (main ingredient material),
Before calcining raw materials₂O₃ (4th sub ingredient material)
And reacting the fourth sub-component material with the main component material in advance.
After obtaining the composition raw material,₂O₅, MnCO₃You
And (SiO₂+ CaO) (first to third subcomponent raw materials)
And baking is performed. In contrast, sample 3
After the preparation of the main ingredient material,
Later, the fourth subcomponent material is added together with the first to third subcomponent materials.
In addition, firing is performed. In comparison between sample 1 and sample 3,
Thus, as in sample 3, the fourth subcomponent raw material is temporarily used as the main component raw material.
If added after baking, high temperature load life (accelerated life of insulation resistance)
Life) is inadequate. On the other hand, the fourth
Add the sub ingredient material before calcining the main ingredient material and react in advance
If you keep it, enough relative dielectric constant and insulation resistance (specific resistance)
Is not reduced by firing in a reducing atmosphere.
Nickel, which is the internal electrode material, does not oxidize,
It was confirmed that an excellent dielectric ceramic composition was obtained.
Was. In addition, it has excellent capacity-temperature characteristics and high temperature load.
Life time (accelerated life of insulation resistance) is about 3 times that of sample 3.
It was confirmed that it could 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 where <m, sample 1 where final m = raw material m ′
About 1.5 times more (by the way,
About 5 times), high temperature load life (accelerated life of insulation resistance)
Life) can be improved.

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

Note that in Samples 5 and 5-1, the fourth
Although the timing of addition of the auxiliary component raw materials is different, the raw material m 'of the main component is 0.985 and the final m
= 0.995. In Sample 6 and Sample 6-1, the raw material m 'of the main component is 0.985, but the final m of the main component is 1.005. Sample 2 and Sample 2-1
In each case, the raw material m 'of the main component is 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 becomes larger. Due to this difference, the high-temperature load life of Sample 5 is about 1.5 times longer than that of Sample 5-1. However, the high-temperature load life of Sample 6 is about 3 times that of Sample 6-1. Sample 2
The high-temperature load life is about five times as long as -1. Therefore, even in the samples (Sample 5, Sample 6, and Sample 2) in which the fourth subcomponent material was added before the main component material was calcined and reacted in advance, the larger the final m value of the main component was, the longer the life was. It was also confirmed that the effect of improvement was remarkable.

Further, in the comparison between Sample 4-1 and Sample 4-2, even if m = 0.885 as in Sample 4-2, the fourth subcomponent raw material reacts in advance with the main component raw material. By using the raw material thus mixed, Y or Y ₂ O
₃ results are more evenly distributed, high temperature load lifetime was improved more than about three times the 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 reacting the fourth subcomponent raw material with the main component raw material in advance.
It was confirmed that it was effective in improving the high temperature load life.

From the results shown in Table 3, the following can be confirmed with respect to the added amount of the fourth subcomponent raw material. When Y was not added at all as in Sample 8, and when the addition amount of Y was 2 mol as in Sample 13, improvement in high temperature load life (accelerated life of insulation resistance) was not observed. On the other hand, in samples 2 to 6 containing a predetermined amount of the fourth subcomponent, 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 when fired in a reducing atmosphere, and does not oxidize nickel as an internal electrode material. A dielectric ceramic composition having excellent reduction resistance was obtained. Further, the capacitance-temperature characteristics were excellent, and the high-temperature load life (accelerated life of insulation resistance) was 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 where m ′ = 0.9 as in Sample 14, even if the fourth sub-component material is preliminarily reacted with the main component material, the dielectric is reduced by firing in a reducing atmosphere, and sufficient insulation resistance can be obtained. Did not.
Further, when m ′ = 1.08 as in Sample 18, even if the fourth subcomponent raw material was previously reacted with the main component raw material, the effect of improving the high temperature load life was not observed. Samples 15 to
17 and Sample 1, both of the final components m = 1.
02, but the raw material m 'value of the main component was Sample 1, Sample 1
7, sample 16 and sample 15 are reduced in this order. On the other hand, the high-temperature load life time of Sample 1, Sample 1
7, sample 16 and sample 15 increase in order. From this, even in a sample in which the fourth sub-component material was added and reacted before calcining of the main component material, as the raw material m 'value of the main component became smaller, that is, as the difference from the final m value became larger, It was also confirmed that the lifetime was improved.

Example 2 The number of moles of the first subcomponent (in terms of V) = 0.2 mole, the number of moles of the second subcomponent (in terms of Mn) = 0.37 mole, and the number of moles of the third subcomponent = (2 .5 + 2.5) mole,
The kind of R as a sub-component was changed as shown in Table 5, and these were added to the powder before calcining in an amount of 0.07 mol in terms of the rare earth element in the oxide, and calcined. The annealing temperature was 1100 ° C. and the holding time was 3 hours. In this way, a plurality of capacitor samples were manufactured, and the defect occurrence rate of the initial insulation resistance (IR) of these samples was calculated. Table 5 shows the results.

[0106]

[Table 5]

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

[0108]

As described above, according to the present invention, a dielectric material which is excellent in reduction resistance during firing, has excellent capacity temperature characteristics after firing, and can improve the accelerated life of insulation resistance. A method for producing a porcelain composition and a method for producing an electronic component such as a chip capacitor with improved reliability can be provided.

[Brief description of the drawings]

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

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 multilayer ceramic capacitor 10 capacitor element body 2 dielectric layer 3 internal electrode layer 4 external electrode

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) H01G 4/12 418 H01G 4/12 418 (72) Inventor Takashi Fukui 1-13-1 Nihonbashi, Chuo-ku, Tokyo No. TDC Corporation (72) Inventor Mikio Takahashi 1-13-1, Nihonbashi, Chuo-ku, Tokyo FTD term (reference) 4G031 AA04 AA05 AA07 AA08 AA09 AA11 AA12 BA09 GA02 5E001 AB03 AE01 AH01 AH09 AJ01 AJ02 5G303 AA01 AB01 AB06 AB11 AB14 AB20 BA12 CA01 CB06 CB08 CB15 CB22 CB26 CB32 CB35 CB39 CB40 CB41 CB43 DA06

Claims (7)

[Claims] 1. Composition formula ｛(Sr_1-xCa_x) O｝
_m・ (Ti_1-y Zr_y) O₂Represented by the group
The molar ratio m in the formula is 0.94 <m <1.08.
The symbol x is 0 ≦ x ≦ 1.00, and the symbol y is 0 ≦ y ≦ 0.
20 and an oxide of R (where R is Sc, Y, La, Ce, P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
o, Er, Tm, Yb and Lu
Dielectric ceramic composition having a fourth subcomponent containing
A method for producing a product, wherein at least a part of a fourth subcomponent material is added to a main component material.
Using the composition material reacted in advance, the dielectric ceramic set
Production of a dielectric porcelain composition characterized by producing a product
Construction method. 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 moles of the main component material,
The method for producing a dielectric porcelain composition according to claim 1 or 2, wherein 0.04 mol or more and less than 2 mol of the fourth subcomponent material are converted in advance in terms of R in the oxide. 4. The method according to claim 1, wherein the main component material has a composition formula ｛(Sr
_1-xCa_x) O｝ _{m '}・ (Ti_1-yZ
r_y) O₂And the molar ratio m 'in the composition formula
Satisfies m ′ ≦ m with respect to the molar ratio m of the final composition.
Item 4. A method for producing the dielectric ceramic composition according to any one of Items 1 to 3.
Law. 5. The dielectric porcelain composition according to claim 4, wherein a material containing at least one element of Sr and Ca is added to the composition raw material, followed by firing to produce the dielectric porcelain composition. Production method. 6. The composition formula ｛(Sr_1-xCa_x) O｝
_m・ (Ti_1-y Zr_y) O₂Represented by the group
The molar ratio m in the formula is 0.94 <m <1.08.
The symbol x is 0 ≦ x ≦ 1.00, and the symbol y is 0 ≦ y ≦ 0.
20 and an oxide of R (where R is Sc, Y, La, Ce, P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
o, Er, Tm, Yb and Lu
Dielectric ceramic composition having a fourth subcomponent containing
Of electronic components having a dielectric layer composed of an object
A method, wherein at least a portion of the fourth subcomponent material is based on the main component material.
Using the composition material reacted in advance, the dielectric ceramic set
A method for producing an electronic component, comprising producing a product. 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. The method of manufacturing the part.