JPH03159109A - Porcelain capacitor and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a porcelain capacitor which can be baked in a non-oxidized atmosphere at a temperature of 1200 deg.C or lower and has a high dielectric constant and also is provided with a dielectric porcelain device whose rate of change in temperature of the dielectric constant is small over a wide temperature range by composing a dielectric porcelain device of basic components made of (Bak-x-yMxLy)OkTiO2 and first and second additive components which are respectively specific. CONSTITUTION:A dielectric porcelain device 12 is composed of 100.0 pts.wt. of basic component, 0.01 to 3.00 pts.wt. of first additive component and 0.2 to 5.0 pts.wt. of second additive component, wherein the basic component is (Bak-x-yMxLy)OkTiO2 (where M refers to one or more among Mg and Zn, L refers to one or more among Ca and Sr, and k, y and x are numerals which respectively satisfy 1.00<=k<=1.05, 0<x<0.10, 0<y<=0.05 and 0.01<=x+y<=0.10), the first additive component is one or more among Cr2O3 and Al2O3 and the second additive component comprises Li2O, SiO2 and MO (where M is one or more among Ba, Sr, Ca Mg and Zn), while a composition range of Li2O, SiO2 and MO is within a region enclosed by five lines which sequentially connect points A to E in the shown triangular figure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a single-layer or laminated JiR ceramic capacitor comprising a dielectric ceramic and at least two electrodes, and a method for manufacturing the same.

[Prior Art] Conventionally, when manufacturing multilayer ceramic capacitors, a conductive paste of noble metal such as platinum or palladium is printed in a desired pattern on a green sheet (unsintered ceramic sheet) made of dielectric ceramic raw material powder. A plurality of these sheets were stacked and pressed together, and sintered in an oxidizing atmosphere at 1300°C to 1600°C. Thereby, the dielectric ceramic and the internal electrode can be obtained at the same time.

As mentioned above, if a noble metal is used, the intended internal electrode can be obtained even if it is sintered at high temperature in an oxidizing atmosphere. However, since precious metals such as platinum and palladium are expensive, the cost of multilayer ceramic capacitors has inevitably increased.

As a solution to the above-mentioned problem, Japanese Patent Publication No. 14607/1987, filed by the applicant, discloses (Bak-xM8) consisting of OkTiO2 (where M is at least one of Mg and Zn). Basic ingredients and L
A dielectric porcelain composition is disclosed that includes an additive component consisting of 120 and SiO2.

In addition, in Japanese Patent Publication No. 61-14608, instead of Li20 and S 102 in the above-mentioned Japanese Patent Publication No. 61-14607, L l 20, 3102, and MO (however, MO is at least one of BaO, CaO, and SrO) are used. A dielectric ceramic composition containing an additive component consisting of (1) is disclosed.

In addition, in Japanese Patent Publication No. 14609/1983, (B a
h-x-y MX L y ) o w T t 02
(However, M is at least one of Mg and Zn, L is at least one of Sr and Ca) and an additive component consisting of L l 20 and SiO2. Disclosed.

Moreover, in Japanese Patent Publication No. 14610/1982, Li2O and 5102
Instead of L l 20, S t O2 and MO (however,
A dielectric ceramic composition containing an additive component consisting of MO (at least one of Bad, CaO, and SrO) is disclosed.

In addition, in Japanese Patent Publication No. 14611/1983, (B a
M) OT i 02 (However, M is Mg,
A dielectric ceramic composition is disclosed that includes a basic component consisting of (at least one of Zn, Sr, and Ca) and additive components consisting of B2O3 and SiO□.

In addition, in Japanese Patent Publication No. 1595/1983, (Ba
M) A basic component consisting of OTiO2 (where M is at least one of Mg, Z-XXkn, Sr, and Ca), and B2O3 and MO (fjfi and MO is BaO1M).
A dielectric ceramic composition containing an additive component consisting of at least one of g05ZnO, SrO, and CaO is disclosed.

In addition, in Japanese Patent Publication No. 1596-1986, BO
A dielectric ceramic composition is disclosed that includes an additive component consisting of S t O2 and MO (where MO3 is at least one of Bad, MgO, ZnO, SrO, and CaO).

The dielectric ceramic composition disclosed in these documents can be obtained by firing in a reducing atmosphere at 1200°C or lower, has a relative dielectric constant of 2000 or more, and has a temperature change rate of capacitance of 125.
It can be adjusted within a range of ±10% from °C to +85 °C.

[Problem to be solved by the invention] Incidentally, with the recent increase in the density of electronic circuits, there is a strong demand for miniaturization of multilayer capacitors. It is desired to further increase the relative permittivity of the body over the relative permittivity of the dielectric ceramic compositions disclosed in the above-mentioned publications.

Therefore, the purpose of the present invention is to use a non-oxidizing atmosphere at 1200°C.
A ceramic capacitor equipped with a dielectric ceramic having a high dielectric constant and a small rate of change in dielectric constant over a wide temperature range, even though it is obtained by firing at the following temperatures, and a method for manufacturing the same. It is about providing.

[Means for Solving the Problems] To achieve the above object, the present invention provides a ceramic capacitor comprising a dielectric ceramic and at least two electrodes in contact with the ceramic, in which the ceramic has a weight of 100.0 parts of the basic component, 0.01 to 3.00 parts by weight of the first additive component, and 0.2 to 5.0 parts by weight of the second additive component, and the basic component is (Ba M L)
-x-yxyk to OTiO2 (However, M is at least one metal of Mg and Zn,
1, at least one metal selected from Ca, Sr, k,
x, y are numerical values that satisfy the following: 1.00≦k≦1.05 0<x<0.10 0<y≦0.05 0.01≦x+y≦0.10),
The first additive component is at least one metal oxide of Cr2O3 and Al2O3, and the second additive component is LiO, S t 02 and MO (however, MO is Ba
The composition range of L120, SiO□, MgO and ZnO is as shown in the triangular diagram showing these compositions in mol%. Said L l 20
A point (A) where S102 is 1 mol%, S102 is 80 mol%, and MO is 19 mol%, and point (A) where 120 is 1 mol%, SiO2 is 39 mol%, and MO is 60 mol%.
B), the above 120 is 30 mol%, and the above 5t02 is 3
0 mol%, the point (C) where the MO is 40 mol%, and the point (C) where the MO is 40 mol%, and the point (C) where the MO is 40 mol%
A point (D) where 120 is 50 mol%, the SiO2 is 50 mol%, and the MO is 0 mol%, and the Li2o is 20 mol%, the S t 02 is 80 mol%, and the MO is 0 mol%. This relates to a capacitor within the area surrounded by five straight lines connecting (E) in sequence. In addition,
In the composition formula showing the basic components, k-x and x of course indicate the number of atoms of each element, Ba is barium, 0 is oxygen, Ti is titanium, Mg is magnesium, and Zn is zinc. The first additive component Cr 203 is chromium oxide,
Al2O3 is aluminum oxide. In the second additive component, Li2O is lithium oxide, S I O2 is silicon oxide, BaO is barium oxide, SrO is strontium oxide, CaO is calcium oxide, MgO is magnesium oxide, and ZnO is zinc oxide.

The invention related to the manufacturing method includes a step of preparing a mixture of the above-mentioned basic component and first and second additive components, and at least #
, a step of making a molded product of the mixture having two electrode parts, a step of firing the molded product having the electrode part in a non-oxidizing atmosphere, and a step of baking the molded product obtained by the firing in an oxidizing atmosphere. The present invention relates to a method of manufacturing a ceramic capacitor including a step of heat treatment.

[Operation and Effect] The dielectric ceramic in the ceramic capacitor of the above invention can be obtained by firing in a non-oxidizing atmosphere at 1200°C or less. Therefore, it becomes possible to manufacture a ceramic capacitor by applying a conductive paste of a base metal such as nickel to a green sheet and firing the green sheet and the conductive paste simultaneously. By setting the composition of the dielectric ceramic within the range specified in the present invention, the dielectric constant can be increased to 3000.
As mentioned above, the dielectric loss tan is 2.5% or less, the resistivity ρ is more than lX106MO・C+a, and the temperature change rate of the dielectric constant is -15% to +15% at -155°C to 125°C (
(based on 25℃), -10% to +10 at -25℃ to 85℃
% (based on 20° C.) can be provided.

[Examples] Next, examples and examples according to the present invention will be described.

First, in order to obtain the composition formula 4 of the basic component according to the present invention in the proportions shown in the x, y, columns of Sample No. 1, in other words, (BaML) OT O,960,040,021,02 102 , more specifically, MO,04=MgO,03
ZnO.

Since ol and L = Ca Sr,
0.02 0.01 0.01 (Ba
Mg Zn Ca Sr
)0.96 0.03 0.01 0.
01 0.0101, 02T l 02, B a CO3 (barium carbonate), Mg0 (magnesium oxide), Zn0 (zinc oxide), CaC03 (calcium carbonate), SrCO3 (strontium carbonate and Prepare TlO2 (titanium oxide) and prepare without adding impurities: BaC0: 1037.72g (equivalent to 0.96 mol part) MgO: 6.62g (equivalent to 0.03 mol part) ZnO
:4.46g (equivalent to 0.01 mole part)CaCO:5.
48g (equivalent to 0.01 mole part) S r Co 3 :
8.09 g < 0, equivalent to 01 mole part) TiOz
: 437.63 g (Weigh out the equivalent of 1,00 mole parts.)

Next, these weighed raw materials are placed in a pot mill.
After adding the alumina balls and 2.5 J of water and stirring for 15 hours, the stirred material was placed in a stainless steel pot and dried at 150°C for 4 hours in a hot air dryer. The material was coarsely pulverized, and the coarsely pulverized material was calcined in the atmosphere at 1200° C. for 2 hours in a tunnel furnace to obtain the basic components of the above compositional formula.

On the other hand, in order to obtain the second additive component of sample Nα1 in Table 2, 0.43 g (1 mole part) of L i 20 and S
68.76g (80 mol parts) of iO2 and BaCO3
10.73g (3.8 mol parts) of
．． 03g (3.8 mol parts) and 5.44g of CaCO3
g (3,8 mol parts) and 2.19 g (3,8 mol parts) of Mgo.
8 mol parts) and 4.42 g (3.8 mol parts) of ZnO
Weigh each and add alcohol to this mixture at 300C.
C was added and stirred for 10 hours using an alumina ball in a polyethylene pot, then pre-calcined in the air at 1000°C for 2 hours, put into an alumina pot with 300cc of water, pulverized with an alumina ball for 15 hours, and then , 15
After drying at 0°C for 4 hours, L i20 was 1 mol%, S
io2 is 80 mol%, MO is 19 mol% (Ba03.
8 mol%±SrO3, 8 mol% + Ca03.8 mol%+
A powder of a second additive component having a composition of 3.8 mol% Mgo and 8 mol% ZnO was obtained. Note that the proportions of BaO, SrO, CaO, MgO, and ZnO, which are the contents of MO, are all 20 mol% as shown in Table 2.

Next, 2 parts by weight (20g) of the second additive component was added to 100 parts by weight (1000g>) of the basic component, and further, the particles were well-aligned with an average particle size of 0.5ttm as the first additive component. 0.1 part by weight of Cr 203 with a purity of 99.0% or more (
1 g), and further, 15% by weight of an organic binder consisting of an aqueous solution of acrylic ester polymer, glycerin, and condensed phosphate based on the total weight of the basic component and the first and second additive components, and , add 50% water by weight,
These were placed in a ball mill, pulverized and mixed to prepare a slurry of porcelain raw materials.

Next, the above slurry is degassed by putting it into a vacuum defoaming machine, and this slurry is put into a reverse roll coater, and the thin film molding obtained from this is continuously coated on a long polyester film, and the same This was dried on a film by heating to 100° C. to obtain an unsintered porcelain sheet with a thickness of about 25 μm. This sheet is long, but it can be divided into 10
Use by cutting into squares with cn angles.

On the other hand, the conductive paste for internal electrodes has an average particle size of 1.5 μm.
10g of nickel powder and 0.9g of ethyl cellulose
was dissolved in 9.1 g of butylcarpitol and placed in a stirrer and stirred for 10 hours. Make 5 patterns of this conductive paste with a length of 14011+ and a width of 7
After printing on one side of the green porcelain sheet through a screen of 0.00, it was dried.

Next, two unsintered porcelain sheets were laminated with the printed surfaces facing up. At this time, the adjacent upper and lower sheets were arranged so that their printed surfaces were shifted by about half in the longitudinal direction of the pattern. Furthermore, four unsintered porcelain sheets with a thickness of 60 μm were laminated on each of the upper and lower surfaces of this laminate.Next, this laminate was subjected to a load of approximately 40 tons in the thickness direction at a temperature of approximately 50°C. It was crimped. Thereafter, this laminate was cut into a grid shape to obtain 50 laminate chips.

Next, this laminate was placed in a furnace capable of firing in an atmosphere, and the temperature was raised to 600° C. at a rate of 100° C./h in an air atmosphere to burn the organic binder. Thereafter, the atmosphere in the furnace was changed from air to an atmosphere containing H2 (2% by volume) and N2 (98% by volume). Then, while maintaining the reducing atmosphere in the furnace as described above, the heating temperature of the laminate was increased from 600°C to the sintering temperature of 1150°C at a rate of 100°C/h to 1150°C (maximum temperature). After holding for 3 hours, 100℃
The temperature was lowered to 600°C at a rate of /h, the atmosphere was changed to air atmosphere (oxidizing atmosphere), 600°C was maintained for 30 minutes to carry out oxidation treatment, and then the laminated sintered chips were cooled to room temperature. Created.

Next, in order to obtain the multilayer ceramic capacitor 10 shown in FIG. 1, a pair of external electrodes 16 were formed on the multilayer sintered chip 15 consisting of three dielectric ceramic layers 12 and two internal electrodes 14. Note that the external electrode 16 is made of zinc and glass frit on the side surface of the sintered chip 15 where the electrode is exposed.
A conductive paste consisting of frit and vehicle is applied and dried, and then heated in the atmosphere for 50 minutes.
Baking was performed at a temperature of 50''C for 15 minutes to form a zinc electrode layer 18, on which a copper layer 20 was formed by electroless plating, and further on this a pbSn solder layer 22 was provided by electroplating. consists of things.

The thickness of the dielectric ceramic layer 12 of this capacitor 10 is 0.0
2 m, and the opposing area of the pair of internal electrodes 14 is 5 tan
S■=25m2. Note that the composition of the ceramic layer 12 after sintering is substantially the same as the mixed composition of the basic components and additive components before sintering.

Next, when the electrical characteristics of the capacitor 10 were measured and the average value was calculated, as shown in Table 3, the relative dielectric constant ε was 3.
800, tan δ is 1.1%, resistivity ρ is 3.8X10
-55 based on 6MΩ・C1l, 25℃ capacitance
Rate of change of capacitance at °C and +125 °C ΔC, ΔC125
-10°5%, 55 +3.6%, -25°C based on 20°C capacitance
The capacitance change rates ΔC and Δ25C85 at 1+85°C were -5.0% and -5.9%.

Note that the electrical characteristics were measured in the following manner.

(A) The relative permittivity ε is at a temperature of 20°C and a frequency of 1k.
Hz, voltage (effective value) 1. The capacitance is measured under OV conditions, and the measured value is 25cm2, which is the opposing area of the pair of internal electrodes 14.
The thickness of the ceramic layer 12 between the pair of internal electrodes 14 is 0.02f.
Calculated from l.

(B) Dielectric loss tan δ (%) was measured under the same conditions as the relative dielectric constant.

(C) Resistivity ρ (MΩ・cn) was calculated by measuring the resistance value between the pair of external electrodes 16 after applying DClooV for 1 minute at a temperature of 20° C. based on this measured value and the dimensions. .

(D) Temperature characteristics of capacitance were measured by placing the sample in a constant temperature bath, -55°C, -25°C, 0°C, +20°C, 25°C,
-1-40℃, +60'C1785℃, +105℃
, +125°C, frequency 1 kHz,
Voltage (effective value) 1. Measure the capacitance under OV conditions,
It was obtained by determining the rate of change at each temperature with respect to the capacitance at 0°C and 25°C.

The preparation method of sample NQI and its characteristics have been described above, but samples NG2 to NG106 also have basic components,
A multilayer ceramic capacitor was manufactured in exactly the same manner as Sample NQI, except that the composition of the second additive component, their proportions, and the firing temperature in a reducing atmosphere were changed as shown in Tables 1 to 3. The electrical characteristics were measured using the same method.

Table 1 shows the composition and amount of the basic component and the first additive component of each sample, and the amount of the second additive component, and Table 2 shows the composition of the second additive component of each sample. show,
Table 3 shows the firing temperature and electrical properties of each sample. Note that x and y between the basic components in Table 1 indicate the number of atoms of each element in the composition formula, that is, the number of Ti atoms. Mg, Zn in the Mx column, which indicates the ratio of the number of atoms of each element when set to 1.
indicates the content of M in the general formula, and the numbers of these atoms are shown in the Mg and Zn columns. Therefore, the value of X is determined by the sum of the number of Mg atoms and the number of Zn atoms. Ca and Sr in the Ly column show the contents of the general formula, and the numbers of these atoms are shown in the Ca and Sr columns. Therefore, the value of y is Ca
It is determined by the sum of the number of atoms of Sr and the number of atoms of Sr. x+y
The column ultimately shows the sum of the numbers of atoms of Mg, Zn, Ca, and Sr. The amounts of the first and second additive components are expressed in parts by weight relative to 100 parts by weight of the basic component. In the column of MO content of the second additive component in Table 2, BaO1
The proportions of Mg01ZnO1SrO and CaO are shown in mol%. In Table 3, the temperature characteristics of capacitance are 2
Based on the capacitance at 5℃, the capacitance change rate at 55℃ and +125℃ is ΔC (%) ΔC (%), the capacitance at 20℃ is -55125. The capacitance change rate in degrees Celsius is expressed as ΔC (%) and ΔC (%).

As is clear from Tables 1 to 3, the samples according to the present invention have a relative dielectric constant ε of 3000 or more and a dielectric loss tan δ of 2.5 when fired in a non-oxidizing atmosphere at 1200°C or less.
% or less, resistivity ρ is 1 x 106 MΩ・C11 or more, temperature change rate of capacitance ΔC-55 and ΔC is -15% to +1
5%, ΔC-25 and 25 ΔC85 are in the range of -10% to +10%, making it possible to obtain a capacitor with desired characteristics. On the other hand, trial: nNo,
11-16.27.32.33.38.39.44.4
5.57-63.71-77.82.83.87.88
．． 97.98.99.105.106 cannot achieve the purpose of the present invention, and therefore they are outside the scope of the present invention.

Although only ΔC, ΔC, ΔC, Δ-55125-25 C85 is shown in Table 3, it is one of the samples belonging to the scope of the present invention. The rate of change ΔC falls within the range of -10% to +10%, and
The various capacitance change rates ΔC in the range of −55° C. to +125° C. fall within the range of −15% to +15%.

Next, the reasons for limiting the composition will be described.

If the values of x and y are zero as shown in sample No. 45.63, ΔC-55 will be outside the range of -15% to +15%, but as shown in sample No. 46 to 49.64.65. ,x+
When the value of y is 0.01, desired electrical characteristics can be obtained. Therefore, the lower limit of the value of x+y is 0.01. On the other hand, as shown in sample Nos. 59-62 and 72-76, when the value of x+y is 0.12, 8085 is outside the range of -10% to +10%, but sample No. 53
~ As shown in 56.69.70, the value of x+y is 0.10
In this case, desired electrical characteristics can be obtained.

However, even if the value of x+y is 0.1, as in sample No. 057.58.71, if the value of y exceeds 0.05, a dense sintered body cannot be obtained.

Therefore, the upper limit of x+y is 0.10, but at the same time y
The upper limit of the value must be set to 0.05.

In addition, Mg and Zn of the M component and Ca and Sr of the M component work almost similarly, and Mg and Zn act in almost the same way.
and Zn or both, and O<y
One or both of Ca and Sr can be used within a range satisfying ≦0.05. It is desirable that the values of x and y be in the range of 0.01 to 0.10 in any case of one or more of the M component and the Y component.

When the value of k is smaller than 1°0, as shown in sample No. 077.83, ρ becomes full at the end of 1xlO6MΩ・CI, which is significantly lower, but as shown in sample No. 078.84, the value of k When is 1.00, desired electrical characteristics can be obtained. Therefore, the lower limit of the value of k is 1.00. On the other hand, the value of k is 1.05 as shown in sample number 82.87.
If it is larger, a dense sintered body cannot be obtained, but as shown in sample No. 81.86, when the value of k is 1.05, desired electrical characteristics can be obtained. Therefore, the upper limit of the value of k is 1.05.

Cr2O3 and/or Al2O3 as the first additive component
When the amount of addition is incense as shown in sample No. 088.99,
ΔC-5 is less than 15%, but sample No. 89
．． As shown in 90.100.101, desired characteristics can be obtained when the amount added is 0.01 part by weight per 100 parts by weight of the basic component.

Therefore, the lower limit of the first additive component is 0.01.

On the other hand, as shown in sample N097.98.105.106, when the amount added is more than 3.0 parts by weight, a dense sintered body cannot be obtained even if fired at 1250°C, but sample Nα94
．． As shown in 95.96.104, when the amount added is 3.0 parts by weight, desired characteristics can be obtained. Therefore, the first
The upper limit of the added components is 3.0 parts by weight. Note that Cr2O3 and A I 203, which are the first additive components, work almost in the same way, and the same result can be obtained even if one selected from them is used or a plurality of them are used. And, regardless of whether the first additive component is one type or multiple types, the amount added is preferably in the range of 0.01 to 3.0.
Note that this first additive component contributes to improving the temperature characteristics of capacitance. That is, by adding the first additive component, the temperature change rate Δ of capacitance in the range of -55°C to 125°C
It becomes possible to easily keep C-5, ~ΔC125 in the range of -15% to +15%, and it also allows for -25°C to 85°
Temperature change rate of capacitance in the range of C ΔC-25 to ΔC8
5 can be easily kept within the range of -10% to +10%, and the fluctuation width of the temperature change rate of capacitance in each temperature range can be reduced. Further, the first additive component has the effect of increasing the resistivity ρ.

When the amount of the second additive component added is zero, sample No. 27
．． As is clear from 33.39, the firing temperature is 1250℃
Although a dense sintered body cannot be obtained even with sample No. 28,
．． As shown in 34.40, when the amount added is 0.2 parts by weight per 100 parts by weight of the basic components, a sintered body having desired electrical properties can be obtained by firing at 1190°C. Therefore, the lower limit of the second additive component is 0.2 parts by weight. On the other hand, as shown in sample No. 32.38.44, it is outside the range of the second added acid, but as shown in sample No. 31.37.43, when the amount added is 5.0 parts by weight, the desired properties are achieved. can be obtained. Therefore, the upper limit of the amount added is 5.0 parts by weight.

A preferred composition of the second additive component is Li O
It can be determined based on a triangular diagram showing the composition ratio of 5ty2 MO. The first point (A) in the triangular diagram is the sample Nα
1 L 120 is 1 mol%, 5102 is 80 mol%, M
The second point (B) shows a composition of 19 mol% O, sample No. 2 has a composition of 1 mol% L 120, 39 mol% SiO2, 60 mol% MO, and the third point (B) Point (C)
is sample No. 3, LiO is 30 mol%, S t
Shows a composition of 30 mol% O2 and 40 mol% MO,
The fourth point (D) shows the composition of sample NQ4 with 50 mol% of LiO, 50 mol% of S t O2, and 0 mol% of MO, and the fifth point (E) shows the composition of sample No. 5 Noshi 120
is 20 mol%, SiO2 is 80 mol%, MO is 0 mol%
The composition of

The composition of the second additive component of the sample that falls within the scope of the present invention is within the area surrounded by five straight lines connecting points 1 to 5 (A) to (E) in the triangular diagram in order. There is. If the composition is within this range, desired electrical characteristics can be obtained.

On the other hand, if the composition of the second additive component is outside the range specified in the present invention, as in samples l1iQ11-16, a dense sintered body cannot be obtained. As shown in (BaO2MgO, ZnO1
It may be either one of Sro or CaO, or it may be in an appropriate ratio as shown in other samples [Modifications] The embodiments of the present invention have been described above, but the present invention The present invention is not limited to this, and the following modifications are possible, for example.

(a) A trace amount of M n O2 (preferably 0.05-0.
1% by weight) may be added to improve sinterability, and other substances may be added as necessary.

(b) The starting materials may be combined with oxides or hydroxides or other compounds other than those shown in the examples.

(c) Even if the temperature of the treatment in the oxidizing atmosphere after the treatment in the non-oxidizing atmosphere during firing is lower than the sintering temperature other than 600°C (preferably in the range of 500°C to 1000°C). good. That is, various changes can be made in consideration of the electrode material such as nickel and the oxidation of the ceramic.

(d) The firing temperature in a non-oxidizing atmosphere can be varied depending on the electrode material. When nickel is used as the internal electrode, hardly any agglomeration of nickel particles occurs in the range of 1050°C to 1200°C.

(e) Sintering may be performed in a neutral atmosphere.

(f> It is of course applicable to general single-layer ceramic capacitors other than multilayer ceramic capacitors.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a multilayer ceramic capacitor according to an embodiment of the present invention, and FIG. 2 is a triangular diagram showing the composition range of additive components. l2...Porcelain layer, 14...Internal electrode, 6...External type pole. Figure 1 Figure 2

Claims (1)

[Scope of Claims] [1] A ceramic capacitor comprising dielectric ceramic and at least two electrodes in contact with the ceramic, wherein the ceramic contains 100.0 parts by weight of a basic component and 0.01 to 0.01 parts by weight of a basic component.
It consists of a first additive component of 3.00 parts by weight and a second additive component of 0.2 to 5.0 parts by weight, and the basic component is (Ba_k_−_x_−_yM_xL_y)O_kTi
O_2 (However, M is at least one metal among Mg and Zn, L is at least one metal among Ca and Sr, k
, y, and x are numerical values that satisfy 1.00≦k≦1.05 0<x<0.10 0<y≦0.05 0.01≦x+y≦0.10), and Added components are Cr_2O_3 and Al_2O_3
The second additive component is at least one metal oxide of Li_2O, SiO_2, and MO (however, MO
is made of at least one metal oxide of BaO, SrO, CaO, MgO, and ZnO, and the Li_
The composition range of 2O, the SiO_2, and the MO is a point (A) where the Li_2O is 1 mol%, the SiO_2 is 80 mol%, and the MO is 19 mol% in a triangular diagram showing these compositions in mol%. , said Li_2
O is 1 mol%, the SiO_2 is 39 mol%, the MO
Point (B) where Li_2O is 60 mol%, point (C) where Li_2O is 30 mol%, SiO_2 is 30 mol%, and MO is 40 mol%, and Li_2O is 50 mol% and the S
Point (D) where iO_2 is 50 mol% and the MO is 0 mol%
, the Li_2O is 20 mol%, and the SiO_2 is 8 mol%.
0 mol %, and the capacitor is within an area surrounded by five straight lines sequentially connecting the point (E) where the MO is 0 mol %. [2] 100.0 parts by weight of basic components, and 0.01 to 3.
00 parts by weight of the first additive component and 0.2 to 5.0 parts by weight of the second additive component, the basic component being (Ba_k_-_x_-_yM_xL_y)O_kTi
O_2 (However, M is at least one metal among Mg and Zn, L is at least one metal among Ca and Sr, k
, x, and y are numerical values that satisfy 1.00≦k≦1.05 0<x<0.10 0<y≦0.05 0.01≦x+y≦0.10), The additive component is at least one metal oxide of Cr_2O_3 and Al_2O_3, and the second additive component is Li_2O, SiO_2, and M
O (however, MO is at least one metal oxide of BaO, SrO, CaO, MgO and ZnO),
In addition, the composition range of the Li_2O, the SiO_2, and the MO is 1 mol% for the Li_2O and 80 mol% for the SiO_2 in a triangular diagram showing these compositions in mol%.
, the point (A) where the MO is 19 mol%, and the Li_2O
is 1 mol%, the SiO_2 is 39 mol%, the MO is 60 mol%, and the Li_2O is 30 mol%.
, the SiO_2 is 30 mol%, the MO is 40 mol%
point (C), the Li_2O is 50 mol%, the Si
Point (D) where O_2 is 50 mol% and the MO is 0 mol%, and the Li_2O is 20 mol% and the SiO_2 is 80 mol%.
mol%, connect the point (E) where the MO is 0 mol% in order 5
a step of preparing a mixture characterized in that it is within an area surrounded by a straight line of a book; a step of making a molded article of the mixture having at least two electrode portions; and a step of forming the molded article having the electrode portions. A method for manufacturing a ceramic capacitor, comprising: firing the molded product in a non-oxidizing atmosphere; and heat-treating the molded product obtained by the firing in an oxidizing atmosphere.