JPH0525377B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a ceramic capacitor having a single-layer or laminated structure consisting of dielectric ceramic and at least two electrodes, and a method for manufacturing the same. [Conventional technology] Conventionally, when manufacturing multilayer ceramic capacitors,
A conductive paste of noble metals such as platinum or palladium is printed in a desired pattern on a green sheet (unsintered porcelain sheet) made of dielectric porcelain raw material powder, multiple sheets are stacked and pressed together, and oxidized at 1300°C to 1600°C. sintered in a neutral atmosphere. 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 _, states that ( _{Bakx Mx} ) _OkTiO2 (where M is at least one of Mg and Zn). species) and Li ₂
A dielectric ceramic composition is disclosed that includes an additive component consisting of O and SiO ₂ . Moreover, in Japanese Patent Publication No. 61-14608, instead of Li ₂ O and SiO ₂ in the above-mentioned Japanese Patent Publication No. 61-14607,
Li ₂ O, SiO ₂ and MO (however, MO is BaO, CaO and
A dielectric ceramic composition containing an additive component consisting of at least one type of SrO is disclosed. In addition, in Special Publication No. 61-14609, (Ba _kxy
M _x L _y ) O _k TiO ₂ (M is at least one of Mg and Zn, L is at least one of Sr and Ca)
A dielectric ceramic composition is disclosed that includes a basic component consisting of Li ₂ O and an additive component consisting of Li 2 O and SiO ₂ . Furthermore, in Japanese Patent Publication No. 61-14610, Li ₂ O, SiO ₂ and MO ( _however , MO is BaO, _CaO
and at least one of SrO) is disclosed. In addition, in Special Publication No. 61-14611, (Ba _kx
M _x )O _k TiO ₂ (where M is at least one of Mg, Zn, Sr, and Ca), and B _{2 O}
A dielectric ceramic composition is disclosed that includes an additive component consisting of SiO ₂ . In addition, in Special Publication No. 1595/1983, (Ba _kx M _x )
A basic component consisting of O _k TiO ₂ (where M is at least one of Mg, Zn, Sr, and Ca) and B ₂ O ₃ .
MO (However, MO is BaO, MgO, ZnO, SrO and
A dielectric ceramic composition containing an additive component consisting of at least one type of CaO is disclosed. In addition, in Japanese Patent Publication No. 62-1596, instead of B ₂ O ₃ and MO in the above-mentioned Japanese Patent Publication No. 62-1595, B ₂ O ₃
and SiO ₂ and MO (however, MO is BaO, MgO, ZnO,
A dielectric ceramic composition containing an additive component consisting of at least one of SrO and CaO is disclosed. The dielectric ceramic compositions disclosed in these are:
It can be obtained by firing in a reducing atmosphere of 1200℃ or less, has a dielectric constant of 2000 or more, and can have a temperature change rate of capacitance of ±10% from -25℃ to +85℃. be. [Problem to be solved by the invention] By the way, with the recent increase in the density of electronic circuits,
There is a strong demand for miniaturization of multilayer capacitors, and in order to meet this demand, the dielectric constant of the dielectric material has been improved to the ratio of the dielectric ceramic compositions disclosed in the above publications without deteriorating the rate of temperature change. It is desired to further increase the dielectric constant. Therefore, the purpose of the present invention is to provide a non-oxidizing atmosphere,
Porcelain capacitors equipped with dielectric porcelain that has 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 a temperature of 1200°C or lower. The object of the present invention is to provide a manufacturing method thereof. [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 is 100.0 parts by weight. It consists of a basic component, a first additive component of 0.01 to 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 _kxy
M _x L _y ) O _k TiO ₂ (However, M is at least one metal among Mg and Zn, L is at least one metal among Ca and Sr,
k, x, 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 first additive component is at least one metal oxide of Cr ₂ O ₃ and Al ₂ O ₃ , and the second additive component is B ₂ O ₃ , SiO _{2 ,} and MO (however, MO is BaO,
At least one of SrO, CaO, MgO and ZnO
and the composition range of the B ₂ O ₃ , the SiO ₂ and the MO is 1 mol % of the B ₂ O ₃ in the triangular diagram showing these compositions in mol %, A point A where SiO ₂ is 80 mol % and the MO is 19 mol %; a point B where the B ₂ O ₃ is 1 mol %, the SiO ₂ is 39 mol %, and the MO is 60 mol %; and the B ₂ O ₃
is 29 mol%, the SiO ₂ is 1 mol%, and the MO is 70
Point C of mol % and said B ₂ O ₃ is 90 mol %, said
A point D where SiO ₂ is 1 mol % and the MO is 9 mol %,
A point E where the B ₂ O ₃ is 90 mol %, the SiO ₂ is 9 mol %, and the MO is 1 mol %, and the B ₂ O ₃ is 19 mol %, the SiO ₂ is 80 mol %, and the MO is This relates to a capacitor that is within an area surrounded by six straight lines connecting points F of 1 mol % in sequence. In addition, in the composition formula showing the basic components, k-x,
Of course, x and k indicate the number of atoms of each element,
Ba is barium, O is oxygen, Ti is titanium, Mg is magnesium, Zn is zinc, Ca is calcium, Sr
is strontium. _Cr2 of the first additive component
_O3 is chromium oxide _{and Al2O3} is aluminum oxide. B ₂ O ₃ in the second additive component is boron oxide,
SiO ₂ 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 the steps of: preparing a mixture of the basic component and the first and second additive components; making a molded product of the mixture having at least two electrode parts; a step of firing the molded article in a non-oxidizing atmosphere;
The present invention relates to a method for manufacturing a ceramic capacitor, which includes a step of heat-treating the molded product obtained by the firing in an oxidizing atmosphere. [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 lower. 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 is 3000 or more, the dielectric loss tan δ is 2.5% or less, and the resistivity ρ is 1 × 10 ⁶
MΩ・cm or more, and the temperature change rate of relative permittivity is -15% to +15% (based on 25°C) from -55°C to 125°C, and -10% to +10% (based on 25°C) from -25°C to 85°C. We can provide capacitors with dielectric ceramics that fall within the temperature range (20℃ standard). [Examples] Next, Examples and Comparative Examples according to the present invention will be described. First, the compositional formula (Ba _kxy M _x L _y )O _k TiO ₂ of the basic component according to the present invention is converted to sample No. 1 in Table 1.
In other words, (Ba _0.96 M _0.04 L _0.02 ) O _1.02 TiO ₂ , more specifically, M _0.04 = Mg _0.03 Zn _0.01 and L _0.02 = Ca _0.01. Sr _0.01
Therefore, in order to obtain (Ba _0.96 Mg _0.03 Zn _0.01 Ca _0.01 Sr _0.01 ) O _1.02 TiO ₂ , BaCO ₃ (barium carbonate), MgO (magnesium oxide), ZnO (zinc oxide), and Prepare TiO ₂ (titanium oxide) without adding any impurities. BaCO ₃ : 1037.72g (equivalent to 0.96 mol part) MgO: 6.62g (equivalent to 0.03 mol part) ZnO: 4.46g (equivalent to 0.01 mol part) CaCO ₃ : 5.48 g (equivalent to 0.01 mole part) SrCO ₃ : 8.09 g (equivalent to 0.01 mole part) TiO ₂ : 437.63 g (equivalent to 1.00 mole part) were weighed. Next, put these weighed raw materials into a pot mill, add an alumina ball and 2.5 ml of water.
After wet stirring for 15 hours, the stirred material was placed in a stainless steel pot and heated to 150°C in a hot air dryer.
It was dried for 4 hours. Next, this dried material is coarsely pulverized, and the coarsely pulverized material is heated in a tunnel furnace at 1200°C in the atmosphere for 20 minutes.
After calcining for a period of time, the basic components having the above composition formula were obtained. On the other hand, in order to obtain the second additive component of sample No. 1 in Table 2, 0.99 g (1 mole part) of B ₂ O ₃ and SiO ₂ were added.
68.38 g (80 mol parts), 10.67 g (3.8 mol parts) of BaCO ₃ , 7.98 g (3.8 mol parts) of SrCO ₃ , and CaCO ₃
5.41g (3.8 mol parts) of MgO and 2.18g (3.8 mol parts) of MgO
Weighed 4.40g (3.8 mol parts) of ZnO and
300 c.c. of alcohol was added to this mixture, stirred for 10 hours using an alumina ball in a polyethylene pot, then pre-calcined in the air at 1000℃ for 2 hours, and poured into an alumina pot with 300 c.c. of water. , crushed with alumina balls for 15 hours, and then dried at 150°C for 4 hours to obtain 1 mol% B ₂ O ₃ , 80 mol% SiO ₂ , 19 mol% MO (BaO 3.8 mol% + SrO
3.8 mol% + CaO 3.8 mol% + MgO 3.8 mol% +
A powder of a second additive component having a composition of 3.8 mol % ZnO was obtained. In addition, the contents of MO, BaO and SrO,
As shown in Table 2, the proportions of CaO, MgO, and ZnO are all 20 mol%. Next, 2 parts by weight (20g) of a second additive component is added to 100 parts by weight (1000g) of the base component, and further,
As the first additive component, 0.1 part by weight (1 g) of Cr ₂ O ₃ with an average particle size of 0.5 μm, well-organized particles, and a purity of 99.0% or more is added, and furthermore, acrylic ester polymer, glycerin, and condensed phosphate. An organic binder consisting of an aqueous solution of 15% by weight is added to the total weight of the basic component and the first and second additive components, and further,
50% by weight of water was added, and the mixture was placed in a ball mill and ground and mixed to prepare a slurry of porcelain raw materials. Next, the above slurry is put into a vacuum deaerator to degas it, and this slurry is put into a reverse roll coater, and the resulting thin film molded product is continuously received on a long polyester film. This was heated to 100°C and dried to obtain an unsintered porcelain sheet with a thickness of about 25 μm. This sheet is long, but it is cut into 10cm squares. On the other hand, the conductive paste for internal electrodes has an average particle size of
10g of 1.5μm nickel powder and ethyl cellulose
A solution of 0.9 g dissolved in 9.1 g of butyl carbitol was placed in a stirrer and stirred for 10 hours. This conductive paste was printed on one side of the unsintered porcelain sheet through a screen having 50 patterns of 14 mm in length and 7 mm in width, and then 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 each having a thickness of 60 μm were laminated on the upper and lower surfaces of this laminate. Next, this laminate was compressed at a temperature of about 50° C. by applying a load of about 40 tons in the thickness direction. 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. After that, the atmosphere of the furnace is changed from the atmosphere to H ₂ (2% by volume) + N ₂
(98% by volume). Then, while maintaining the reducing atmosphere in the furnace as described above, the laminate heating temperature was increased from 600°C to the sintering temperature of 1150°C.
Raise the temperature at a rate of 100℃/h to 1150℃ (maximum temperature)
After holding for 3 hours, the temperature was lowered to 600°C at a rate of 100°C/h, and the atmosphere was changed to air (oxidizing atmosphere).
Instead, oxidation treatment was performed by holding the temperature at 600°C for 30 minutes, and then cooling to room temperature to produce a laminated sintered chip. Next, in order to obtain the multilayer ceramic capacitor 10 shown in FIG. 1, a pair of external electrodes 16 were formed on a multilayer sintered chip 15 consisting of three dielectric ceramic layers 12 and two internal electrodes 14. In addition, external electrode 1
In step 6, a conductive paste consisting of zinc, glass frit, and vehicle is applied to the side surface of the sintered chip 15 where the electrodes are exposed, dried, and then heated in the atmosphere at a temperature of 550°C. A zinc electrode layer 18 is formed by baking for 15 minutes, a copper layer 20 is formed thereon by electroless plating, and a Pb-Sn solder layer 22 is further formed on this by electroplating. The thickness of the dielectric ceramic layer 12 of this capacitor 10 is 0.02 mm, and the opposing area of a pair of internal electrodes 14 is 5 mm.
×5mm= ^25mm2 . Note that the porcelain layer 12 after sintering
The composition of is substantially the same as the mixed composition of the basic components and additive components before sintering. Next, the electrical characteristics of the capacitor 10 were measured and the average values were calculated. As shown in Table 3, the relative dielectric constant ε _s is 3810, the tan δ is 1/1%, and the resistivity ρ is
3.8×10 ⁶ MΩ・cm, capacitance change rate ΔC _-55 at -55℃ and +125℃ based on capacitance at 25℃,
ΔC ₁₂₅ is -10.6%, +3.6%, capacitance change rate ΔC _-25 at -25℃ and +85℃ based on capacitance at 20℃, ΔC ₈₅ is -5.1%, -6.1%. It was hot. Note that the electrical characteristics were measured in the following manner. (A) The relative permittivity ε _s is determined by measuring the capacitance under the conditions of temperature 20°C, frequency 1kHz, and voltage (effective value) 1.0V, and the measured value is calculated using the opposing area of 25 mm ² of the pair of internal electrodes 14 and the pair of Thickness of porcelain layer 12 between internal electrodes 14: 0.02
Calculated from mm. (B) Dielectric loss tanδ (%) was measured under the same conditions as the relative dielectric constant. (C) Resistivity ρ (MΩ・cm) at a temperature of 20℃
After applying DC 100V for 1 minute, the resistance value between the pair of external electrodes 16 was measured, and calculated based on this measured value and the dimensions. (D) Temperature characteristics of capacitance are measured by placing the sample in a thermostatic chamber at -55°C, -25°C, 0°C, +20°C, 25°C, +40°C.
℃, +60℃, +85℃, +105℃, +125℃ under the conditions of frequency 1kHz and voltage (effective value) 1.0V, and the capacitance at 20℃ and 25℃ is measured. It was obtained by determining the rate of change at each temperature. The preparation method and characteristics of sample No. 1 have been described above, but samples No. 2 to 99 have also been described regarding the composition of the basic component, the first and second additive components, their ratios, and the reducing atmosphere. Multilayer ceramic capacitors were manufactured in exactly the same manner as Sample No. 1, except that the firing temperature was changed as shown in Tables 1 to 3, and the electrical characteristics were measured in the same manner. 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. Table 3 shows the firing temperature and electrical properties of each sample. Note that x, y, and k in the column of basic components in Table 1 indicate the number of atoms of each element in the composition formula, that is, the ratio of the number of atoms of each element when the number of atoms of Ti is 1. Mg and Zn in the x column are
The contents of M in the general formula are shown, the Mg and Zn columns show the number of these atoms, the y column Ca and Sr show the contents of the general formula L, and the Ca and Sr columns show these atoms. The number of atoms is shown, and the total value (y) of these is shown in the total column. In the x+y column, Mg, Zn, Ca,
The sum of the numbers of Sr atoms is shown. 1st and 2nd
The amount of the additional component added is shown in parts by weight based on 100 parts by weight of the basic component. The MO content column of the second additive component in Table 2 contains BaO, MgO, ZnO,
The proportions of SrO and CaO are shown in mol%. Third
In the table, the temperature characteristics of capacitance are as follows: ΔC _-55 (%) ΔC ₁₂₅ (%), capacitance change rate at -55°C and +125°C based on the capacitance at 25°C, The capacitance change rate at -25°C and +85°C based on the capacitance is shown as ΔC _-25 (%) and ΔC ₈₅ (%).

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[Table] As is clear from Tables 1 to 3, the samples according to the present invention have a relative dielectric constant ε _s of 3000 or more and a dielectric loss tan δ when fired in a non-oxidizing atmosphere at 1200°C or lower.
2.5% or less, resistivity ρ is 1×10 ⁶ MΩ・cm or more, temperature change rate of capacitance ΔC _-55 and ΔC ₁₂₅ is -15% ~
+15%, ΔC _-25 and ΔC ₈₅ are in the range of -10% to +10%, making it possible to obtain a capacitor with desired characteristics. On the other hand, sample Nos. 7 to 10, 26, 31, 32, 37, 38,
50-56, 64-70, 75, 76, 80, 81, 90, 91, 92,
98 and 99 cannot achieve the object of the present invention. Therefore, these are outside the scope of the present invention. Although only ΔC _-55 , ΔC ₁₂₅ , ΔC _-25 and ΔC ₈₅ are shown in Table 3, various capacitance changes in the range of -25°C to +85°C of samples belonging to the scope of the present invention are shown. The rate 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. are in the range of −15% to +15%. Next, the reasons for limiting the composition will be described. If the value of x+y is zero as shown in sample No. 38 and 56, ΔC _-55 will be outside the range of -15% to +15% and ΔC _-25 will be outside the range of -10% to +15%. However, the sample
As shown in Nos. 39, 40, 41, 42, 57, and 58, when the value of x+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. 52-55 and 65-69,
When the value of x+y is 0.12, ΔC ₈₅ is -10% to +
Although it is outside the range of 10%, desired electrical characteristics can be obtained when the value of x+y is 0.10, as shown in Sample Nos. 46 to 49, 62, and 63. However, as shown in sample Nos. 50, 51, and 64, even if the value of x+y is 0.10, if the value of y exceeds 0.05, ΔC ₈₅ is out of the range. Therefore, the upper limit of x+y is 0.10, but at the same time the upper limit of y must be set to 0.05. In addition, Mg and Zn of M component and Ca and L component
Sr works in almost the same way, and one or both of Mg and Zn should be used within the range that satisfies 0<x<0.10, and Ca and Sr should be used within the range that satisfies 0<y≦0.05.
One or both of these can be used. It is desirable that the value of x+y be in the range of 0.01 to 0.10 in either case of one or more of the M component and the L component. When the value of k is smaller than 1.0, as shown in samples No. 70 and 76, ρ becomes less than 1×10 ⁶ MΩ・cm, which is significantly lower, but as shown in samples No. 71 and 77, , k 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, as shown in sample Nos. 75 and 80, the value of k is
When the value of k is greater than 1.05, a dense sintered body cannot be obtained, but as shown in Sample Nos. 74 and 79, 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. Cr ₂ O ₃ and/or Al ₂ O ₃ as the first additive component
If the amount added is zero as shown in sample Nos. 81 and 92,
Although ΔC _-55 is less than -15%, sample No. 82, 83,
As shown in 93 and 94, when the amount added is 0.01 part by weight per 100 parts by weight of the basic component, desired characteristics can be obtained. Therefore, the lower limit of the first additive component is
It is 0.01. On the other hand, when the amount added is more than 3.0 parts by weight as shown in sample Nos. 90, 91, 98, and 99, 1250
Although a dense sintered body cannot be obtained even if fired at 0.degree. C., desired characteristics can be obtained when the amount added is 3.0 parts by weight, as shown in sample Nos. 87, 88, 89, and 97. Therefore, the upper limit of the first additive component is 3.0 parts by weight.
Note that Cr ₂ O ₃ and Al ₂ O ₃ , which are the first additive components, work in almost the same way, and the same results can be obtained even if one selected from them or a combination of them is used. It will be done. 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 is -55℃~
Temperature change rate of capacitance ΔC in the range of 125℃ _-55 ~
It becomes possible to easily keep ΔC ₁₂₅ within the range of -15% to +15%, and the temperature change rate of capacitance ΔC _-25 to ΔC ₈₅ in the range of -25°C to 85°C can be reduced to -10%. +
It becomes possible to easily keep the capacitance within a range of 10%, and it is possible to reduce the fluctuation range of the temperature change rate of capacitance in each temperature range. Further, the first additive component has the effect of slightly increasing the resistivity ρ. If the amount of the second additive component is zero, the sample
As is clear from Nos. 26 and 32, a dense sintered body cannot be obtained even at a firing temperature of 1250°C, but sample No.
27 and 33, 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 Nos. 31 and 37, when the amount of the second additive component is 6.0 parts by weight, ε _s is 3000 parts by weight.
Furthermore, ΔC _-55 is outside the range of -15% to +15%, but as shown in sample Nos. 30 and 36, the amount added is
In the case of 5.0 parts by weight, desired properties can be obtained. Therefore, the upper limit of the amount added is 5.0 parts by weight. The preferred composition of the second additive component is shown in FIG.
It can be determined based on a triangular diagram showing the composition ratio of _{B2O3 - SiO2} -MO. First point A of the triangular diagram
indicates a composition of sample No. 1 with 1 mol% B ₂ O ₃ , 80 mol% SiO ₂ , and 19 mol% MO, and the second point B
indicates the composition of sample No. 2 with 1 mol% B ₂ O ₃ , 39 mol% SiO ₂ , and 60 mol% MO, and the third point C
indicates the composition of sample No. 3 with 29 mol% B ₂ O ₃ , 1 mol% SiO ₂ , and 70 mol% MO, and the fourth point D
indicates the composition of sample No. 4 with 90 mol% B ₂ O ₃ , 1 mol% SiO ₂ , and 9 mol% MO, and the fifth point E
indicates the composition of Sample No. 5 with 90 mol% of B ₂ O ₃ , 9 mol% of SiO _2, and 1 mol% of MO, and the sixth point F shows the composition of Sample No. 6 with 19% of B ₂ O ₃ mol%, _SiO2 80 mol%,
It shows a composition of 1 mol% MO. The composition of the second additive component of the sample belonging to the scope of the present invention is 6
The composition is within the area surrounded by straight lines in the book.
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 falls outside the range specified in the present invention, as in Samples Nos. 7 to 10, a dense sintered body cannot be obtained. In addition, the MO component may be any one of BaO, MgO, ZnO, SrO, CaO as shown in Sample Nos. 17 to 21, or may be in an appropriate ratio as shown in other samples. . [Modifications] Although the embodiments of the present invention have been described above, the present invention is not limited thereto, and, for example, the following modifications are possible. (a) A trace amount of a mineralizing agent such as MnO ₂ (preferably 0.05 to 0.1% by weight) may be added to the basic components to improve the sinterability, within a range that does not impede the object of the present invention. Further, other substances may be added as necessary. (b) The starting materials may be hydroxides or other compounds other than those shown in the examples. (c) 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℃ (preferably 500℃ to 1000℃).
range). That is, various changes can be made in consideration of the electrode material such as nickel and the oxidation of porcelain. (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, almost no aggregation 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 drawings]

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. 12...Porcelain layer, 14...Internal electrode, 16...
external electrode.

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 3.00 parts by weight of a first component. It consists of an additive component and 0.2 to 5.0 parts by weight of a second additive component, and the basic component is ( _Bakxy M _x L _y )O _k TiO ₂ (where M is at least one of Mg and Zn). metal, L is at least one metal among Ca and Sr,
k, x, y are numerical values satisfying 1.00≦k≦1.05 0<x<0.10 0<y≦0.05 0.01≦x+y≦0.10), and the first additive component is Cr ₂ O ₃ and Al ₂ O ₃ The second additive component is at least one metal oxide selected from the group consisting of B ₂ O ₃ , SiO ₂ and MO (wherein MO is at least one metal oxide selected from BaO, SrO, CaO, MgO and ZnO). In a triangular diagram in which the composition ranges of the B ₂ O ₃ , the SiO ₂ and the MO are expressed in mol %, the B ₂ O ₃ is 1 mol %, the SiO ₂ is 80 mol%,
Point A where the MO is 19 mol %, the B ₂ O ₃ is 1 mol %, the SiO ₂ is 39 mol %,
Point B where the MO is 60 mol%, the B ₂ O ₃ is 29 mol%, the SiO ₂ is 1 mol%,
Point C where the MO is 70 mol %, the B ₂ O ₃ is 90 mol %, the SiO ₂ is 1 mol %,
Point D where the MO is 9 mol %, the B ₂ O ₃ is 90 mol %, the SiO ₂ is 9 mol %,
Point E where the MO is 1 mol %, the B ₂ O ₃ is 19 mol %, the SiO ₂ is 80 mol %,
A capacitor characterized in that the MO is within a region surrounded by six straight lines sequentially connecting points F of 1 mol %. 2 Consists of 100.0 parts by weight 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 _kxy M _x L _y ) O _k TiO ₂ (However, M is at least one metal among Mg and Zn, L is at least one metal among Ca and Sr,
k, x, 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 first additive component is at least one metal oxide of Cr ₂ O ₃ and Al ₂ O ₃ , and the second additive component is B ₂ O ₃ , SiO _{2 ,} and MO (however, MO is BaO,
At least one of SrO, CaO, MgO and ZnO
and the composition range of the B ₂ O ₃ , the SiO ₂ and the MO is 1 mol % of the B ₂ O ₃ in the triangular diagram showing these compositions in mol %, A point A where SiO ₂ is 80 mol % and the MO is 19 mol %; a point B where the B ₂ O ₃ is 1 mol %, the SiO ₂ is 39 mol %, and the MO is 60 mol %; and the B ₂ O ₃
is 29 mol%, the SiO ₂ is 1 mol%, and the MO is 70
Point C of mol % and said B ₂ O ₃ is 90 mol %, said
A point D where SiO ₂ is 1 mol % and the MO is 9 mol %,
A point E where the B ₂ O ₃ is 90 mol %, the SiO ₂ is 9 mol %, and the MO is 1 mol %, and the B ₂ O ₃ is 19 mol %, the SiO ₂ is 80 mol %, and the MO is A step of preparing a mixture characterized by being within an area surrounded by six straight lines connecting points F of 1 mol% in order, and producing a molded product of the mixture having at least two electrode parts. A method for manufacturing a ceramic capacitor, comprising: firing the molded product having the electrode portion in a non-oxidizing atmosphere; and heat-treating the molded product obtained by the firing in an oxidizing atmosphere.