JPH03278422A - Porcelain capacitor and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve relative permittivity by mixing 100 pts.wt. of specific basic component, 3.0 pts.wt. or less of first specific additive component, and 0.2-5 pts.wt. of second specific additive component of a specific range of a triangular diagram of mol% of composition range, and firing the mixture to form a dielectric porcelain composition. CONSTITUTION:100 pts.wt. of basic component represented by formula I, 3.0 pts.wt. or less of first additive component containing Cr2O3 and/or AlO3 and 0.2-5 pts.wt. of second additive component containing Li2O, SiO2 and MO (MO is one or more types of metal oxide selected from BaO, SrO, CaO, MgO and ZnO) are mixed and baked. The composition range of the second additive component is disposed in a range surrounded by straight lines for sequentially coupling points A-B-C-D-E-F-A of a triangular diagram shown by mole % of the composition range of the second additive component, and hence its relative permittivity can be set to 3000 or more. In formula I, M; Mg and/or Zn, L; Ca and/or Sr, R; one or more types or metal elements selected from Sc, Y, Gd, Dy, Ho, Er, Yb, Tb, Tm, Lu. Letters alpha, k, x, z, y; numerical values for satisfying formula II.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a ceramic capacitor having a single-layer or laminated structure in which a dielectric ceramic layer is sandwiched between at least two internal 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 an unsintered porcelain sheet (green sheet) made of dielectric porcelain raw material powder. A plurality of these sheets were stacked and pressed together, and fired at 1300° C. to 1600° C. in an oxidizing atmosphere.

Through this firing, the unsintered porcelain sheet made of the dielectric porcelain raw material powder becomes a dielectric porcelain layer, and the conductive paste of noble metal such as platinum or palladium becomes an internal electrode.

As mentioned above, if a conductive paste containing a noble metal such as platinum or palladium is used as the main component, the desired internal electrode can be obtained even if it is fired at a high temperature of 1300°C to 1600°C in an oxidizing atmosphere. I can do it.

However, since precious metals such as platinum and palladium are expensive, the cost of multilayer ceramic capacitors has inevitably increased.

Japanese Patent Publication No. 14607/1983, filed by the applicant, discloses (B
A dielectric ceramic composition is disclosed that includes a basic component consisting of am-x MxlO+t T i Ox (where M is Mg and/or Zn) and additive components consisting of Li2O and SiO2.

In addition, Japanese Patent Publication No. 61-14608 discloses that the dielectric ceramic composition described in Japanese Patent Publication No. 61-14607 is
k, L i 20 , S instead of i2O and 5if2
i O2 and MO (however, MO is BaO, CaO and S
one or more metal oxides selected from rO)
A dielectric ceramic composition is disclosed that includes an additive component consisting of.

In addition, in Japanese Patent Publication No. 61-1.4609, (B a
, -*-y Mz LylOkT i 02 (However, M is Mg and/or Zn, L is Sr and/or Ca
A dielectric ceramic composition is disclosed that includes a basic component consisting of ) and additive components consisting of L iz O and SiO□.

Further, in Japanese Patent Publication No. 14610/1982, k, Li 2 instead of L i t O and SiO□ in the dielectric ceramic composition described in Japanese Patent Publication No. 61-14609 mentioned above
0. S i Ox and MO (however, MO is Ear, C
A dielectric ceramic composition is disclosed that includes an additive component consisting of one or more metal oxides selected from aO and SrO.

In addition, in Japanese Patent Publication No. 14611/1983, (B ai
+-x M-)okT i 02 (However, M is Mg
.

one or more metal elements selected from Zn, Sr and Ca), and B2O3 and SiO
A dielectric ceramic composition containing an additive component consisting of □ is disclosed.

Also, in Japanese Patent Publication No. 62-1.595.

(B ay-x M,) O, T i 02 (However, M is Mg.

A basic component consisting of one or more metal elements selected from Zn, Sr, and Ca), B2O, and MO (
However, MO is Bao.

A dielectric ceramic composition containing an additive component consisting of one or more metal oxides selected from MgO, ZnO, SrO, and CaO is disclosed.

In addition, Japanese Patent Publication No. 62-1596 discloses that the dielectric ceramic composition B, 0
k instead of 3 and MO, Bias sio! and MO(
However, MO is BaO, MgO, ZnO, SrO and Ca
A dielectric ceramic composition is disclosed that includes an additive component consisting of one or more metal oxides selected from O.

If the dielectric ceramic composition disclosed in these documents is used as a dielectric layer, it can be heated to 1200°C in a reducing atmosphere.
Porcelain capacitors can be obtained by firing at the following temperatures:
Moreover, the relative permittivity of the dielectric ceramic composition is 2000 or more, and the temperature change rate of the relative permittivity is 1 at -25°C to +85°C.
It can be set in the range of 0%.

[Problems to be solved by the invention] By the way, with the increasing density of electronic circuits in recent years,
There is a very strong demand for miniaturization of ceramic capacitors, and it has been desired to develop a ceramic capacitor equipped with a dielectric ceramic composition having a higher dielectric constant than the dielectric ceramic compositions disclosed in the above-mentioned publications. .

In addition, since ceramic capacitors are conveniently used in various environments, dielectric ceramic compositions with a smaller rate of change in dielectric constant over a wider temperature range than the dielectric ceramic compositions disclosed in the above-mentioned publications are used. There was a desire to develop a ceramic capacitor with this feature.

Therefore, the object of the present invention is to
Although it is obtained by firing at a temperature of 1200°C or less, it has a relative dielectric constant of 3000 or more and a dielectric loss ta.
nδ is 2.5% or less, resistivity ρ is 1X10'Ω・cm or more, and the temperature change rate of relative dielectric constant is 155℃ to 125℃
-15% to +15% (based on 25℃), -25℃ to 8
It is an object of the present invention to provide a ceramic capacitor equipped with a dielectric ceramic composition whose temperature ranges from -10% to +10% (based on 20°C) at 5°C, and a method for manufacturing the same.

[Means for Solving the Problems 1] A ceramic capacitor according to the present invention includes a dielectric ceramic layer made of a dielectric ceramic composition, and at least two internal electrodes sandwiching the dielectric ceramic layer. In the ceramic capacitor, the dielectric ceramic composition comprises 100 parts by weight of a basic component;
It consists of a calcined mixture of a first additive component of 3.0 parts by weight or less and a second additive component of 0.2 to 5 parts by weight, and the basic component is (1-αl (tBa+t-X -ffiMXt, ZI
L (Ti 1-yRyl O□-27□) + αBaZ
r0s (However, M is Mg and/or Zn, L is Ca and/or Zn, L is Sc, Y, Gd, Dy.

1 selected from Ho, Er, Yb, Tb, Tm, Lu
species or two or more metals, a, k, x.

z, y are 0, 005 ≦a≦0.04 1 , 00≦≦1 , 05 0<x<0.10 0<z ≦0.05 0, 01 ≦x+z ≦0.10 o<y≦0 .04), and the first
The additive component is Crz Ox and/or A1°0. The second additive component is L i x O, S i O2, and M
O (However, MO is B a O, S r O, Ca O,
(one or more metal oxides selected from MgO and ZnO), and the composition range of the Li2O, the SiO2, and the MO is a triangular diagram showing these compositions in mol%. A first point A having a composition of 1 mol % of the Li z O, 80 mol % of the SiO2, and 19 mol % of the MO; 39
mol %, a second point B where the MO has a composition of 60 mol %
and the L i t O is 30 mol % and the SiO2 is 30 mol %.
mol%, a third point C where the MO has a composition of 40 mol%
and the Li t O is 50 mol % and the Si O 2 is 50 mol %.
a fourth dot showing a composition of 0 mol%° and 0 mol% of the MO; 20 mol% of the Li-0 and 80 mol% of the SiO□;
, and the fifth point E where the MO has a composition of 0 mol %.

Here, the reason why 0.005≦α≦0.04 is set is that a is 0.
．． In the range of 005≦α≦0.04, a dielectric ceramic composition having desired electrical properties can be obtained, but when a is 0.
．． When it becomes less than 005, the temperature change rate of capacitance △C-2
5 is outside the range of -10% to +10%, ΔC-55 is -15
% to +15%, and if α exceeds 0.04, the temperature change rate ΔCas of capacitance will be -10% to +10%.
This is because it is outside the range of .

Also, 1.00≦≦1.05.

When k is in the range of 1.00≦1.05, a dielectric ceramic composition having desired electrical properties can be obtained.
becomes less than 1.00, the resistivity ρ becomes lX10'MΩ・
This is because when k is less than cm, it is significantly lower, and when k exceeds 1.05, a dense sintered body cannot be obtained.

Also, if 0.01≦x+z≦0.10, then x+z
In the range of 0.01≦x+z≦o, io, a dielectric ceramic composition with desired electrical properties can be obtained;
becomes less than 0.01, the rate of temperature change in capacitance I ΔC-
2, Outside the range of -10% to +10%, ΔC-55 is -1
If it is outside the range of 5% to +15% and X+Z exceeds 0.10, the temperature change of capacitance Cas will be -10% to +
This is because it is outside the 10% range.

However, even if x+z is within the range of 0.01≦x+z≦0.10, if Z exceeds 0.05, a dielectric ceramic composition having desired electrical properties cannot be obtained. Therefore, the upper limit value of X+Z is 0.10, but at the same time the upper limit value of Z must be set to 0.05.

In addition, Mg and Zn of the M component and Ca and Sr of the L component are f
Similarly, one or both of Mg and Zn can be used within the range that satisfies 2O<x<0.10, and O<z
One or both of Ca and Sr can be used within a range satisfying ≦0.05.

It is desirable that the value of X+Z 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.

Also, the reason why o<y≦0.04 is set is that y is 0<y≦0.
If y is in the range of 0.04, a dielectric ceramic composition with desired electrical properties can be obtained, but if y exceeds 0.04, a dense sintered body cannot be obtained.

Then, the R components Sc, Y, Dy, and Ho.

Er, Yb work in the same way as f, and 1 selected from these
Similar results can be obtained using one or more. Regardless of whether there is one type of R component or multiple types of R components, it is desirable that the value of y be in the range of 0.04 or less. Further, if y is 0.04 or less, even a trace amount close to 2O has a certain effect.

In the composition formula, the component represented by R contributes to improving the temperature characteristics of capacitance. That is, by adding the R component, the temperature
Temperature change rate of capacitance ΔC-5, ~Δ in the range of 25℃
C1□ can be easily kept within the range of -15% to +15%, and the temperature change rate of capacitance △C-25 to △CAs in the range of -25°C to 85°C can be kept within the range of -25% to +15%. 10%~
It becomes possible to easily keep the capacitance within the range of +10%, and it is possible to reduce the fluctuation range of the temperature change rate of capacitance in each temperature range.

Moreover, the R component has the effect of increasing the resistivity p and the effect of increasing sinterability.

In addition, in the composition formula showing the basic components, X.

y and z indicate the number of atoms of each element, and 1-a and α are IB&m-x-z'tA*Lx)Ok(Tt+-yRy
The ratio of lOx-yyz to Ba1rn3 in the second term is shown in moles.

In addition, among the basic components, a trace amount of M n Oz (preferably 0.05 to O,
A mineralizing agent such as 1% by weight) may be added to improve sinterability. Further, other substances may be added as necessary.

In addition, starting materials for obtaining the basic components may be other than those shown in Examples, such as BaO and SrO.

It may also be an oxide or hydroxide such as CaO or other compounds.

Next, the upper limit of the first additive component was set at 3.0 parts by weight.
When the amount of the first additive component added is 3.0 parts by weight, a dielectric ceramic composition having desired electrical properties can be obtained; however, when the amount exceeds 3.01 parts by weight, This is because a dense sintered body cannot be obtained even if fired at ℃.

Even if the first additive component is in an extremely small amount (0<first additive component) within the range of 3.0 parts by weight or less, it has a certain effect. However, in consideration of variations in electrical properties during mass production, it is desirable to add 0.001 part by weight or more.

Note that the first additional components are CrzOs and A1□O.

The toba works in the same way as the i, and the same result can be obtained by using one selected from these, or by using a plurality of them.

Whether the first additive component is one type or multiple types, the amount added is desirably within a range of 3.0 parts by weight or less.

This first additive component contributes to improving the temperature characteristics of capacitance. That is, by adding the first additive component, the temperature of -55°C to 1
Temperature change rate of capacitance ΔC-55 to Δ in the range of 25℃
CI□5 can be easily kept within the range of -15% to +15%, and the temperature change rate of capacitance △C-25 to ΔCs5 in the range of -25°C to 85°C can be set to -10%. %～
It becomes possible to easily keep the capacitance within the 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.

Next, the second additive component was set in the range of 0.2 to 5 parts by weight relative to 100 parts by weight of the basic component. A dielectric ceramic composition having electrical properties can be obtained, but if the second additive component is less than 0.2 parts by weight, the firing temperature will be 1250°C.
However, a dense sintered body cannot be obtained even if the second additive component is 5
If it exceeds parts by weight, the relative dielectric constant ε becomes less than 3000, and the temperature change rate ΔCa5 of capacitance is -10% to +
This is because it is outside the 10% range.

The composition of the second additive component is Li2O, S i 02 and MO
In the triangular diagram showing the composition in mol%, the first to
5, the area surrounded by the five straight lines connecting A-E in this order is the reason why if the composition of the second additive component is within this area, the dielectric material has the desired electrical characteristics. Although a ceramic composition can be obtained, if the composition of the second additive component is outside this range, a dense sintered body cannot be obtained.

Note that the MO acid components are BaO, MgO, and ZnO.

It may be either one of SrO or CaO, or it may be in an appropriate ratio. Further, the starting materials for the additive components may be other compounds such as oxides and hydroxides other than those shown in the examples.

Next, the method for manufacturing a ceramic capacitor according to the present invention includes the above basic components and the first method. a step of preparing a mixture of unsintered porcelain powder comprising a second additive component; a step of forming an unsintered porcelain sheet comprising the mixture; The method comprises a step of forming a laminate sandwiched between films, a step of firing the laminate in a non-oxidizing atmosphere, and a step of heat-treating the fired laminate in an oxidizing atmosphere. be.

Here, the firing temperature in the non-oxidizing atmosphere can be varied depending on the electrode material.

When using nickel as the internal electrode, the temperature is 1050℃~12
Almost no aggregation of nickel particles occurs in the temperature range of 00°C. Further, the non-oxidizing atmosphere may be not only a reducing atmosphere such as H2 or GO, but also a neutral atmosphere such as N2 or Ar.

Furthermore, the temperature of the heat treatment in the oxidizing atmosphere can be varied in consideration of the electrode material such as nickel and the oxidation of the ceramic.

Although the temperature of this heat treatment was set to 600°C in the example, it is not limited thereto, and may be any temperature lower than the sintering temperature, preferably in the range of 500°C to 1000°C.

Note that the present invention is of course applicable to -M single-layer ceramic capacitors other than multilayer ceramic capacitors.

[Example 1] First, the preparation method of sample N011 shown in Table 1 and its electrical characteristics will be explained.

Weigh each of the compounds of 1 ball of Gosei Doudan, and mix the stiff compound with Botmill fpot m1L11k, alumina ball, and 2 parts of water.
．． The mixture was added at 5° C. and stirred and mixed for 15 hours to obtain a raw material mixture.

Here, the weight (g) and molar parts of the compound of Formulation 1 are the first term (BaM-++-zM++LzlOi+(Tit-yR
y)02-yza (hereinafter referred to as the first basic component) is (B a a, 96M go, asS ro, o
+) O1, o2 (T 1 o, e*Y b n, al
) Or, ee5.

Next, put this raw material mixture into a stainless steel pot, dry it at 150°C for 4 hours using a hot air dryer, coarsely crush this dried raw material mixture, and use a tunnel furnace to crush this coarsely crushed raw material mixture. The powder was calcined for 2 hours at about 1200° C. to obtain a powder of the first basic component in the composition formula (1) of the above basic component.

In addition, BaZrOx in the second term of the basic component composition formula (1)
(hereinafter referred to as the second basic component), k, Ba
Weighed 615.61g of the former and 384.39g of the latter so that the moles of C0- and Zr02 were equal, mixed them, dried them, pulverized them, and then heated them at about 1250°C in the atmosphere. It was calcined for 2 hours.

Then, as shown in sample No. 61 in Table 1, k, 98 mol parts (976.28 g) of powder of the first basic component so that k, 1-0 is 0.98 mol, and a is 0.02 mol, 2 molar parts f23.85 g) of powder of the second basic component were mixed to obtain 1000 g of the basic component.

Preparation of the second additive composition Also, each of the compounds of Formulation 2 was weighed and mixed, 300 cc of alcohol was added to this mixture, and the mixture was stirred for 10 hours using an alumina ball in a polyethylene pot.
Thereafter, it was temporarily formed in the atmosphere at a temperature of 1000° C. for 2 hours.

Here, the weight (g) of the compound of formulation 2 is as follows: L 120 is 1 mol%, SiOz is 80 mol%, MO is 19 mol% (BaOf3.8 mol%l+ca, 0(9.5 mol%
)+Mg0f5.7 mol%)) This is a value calculated to have a composition of

Next, put the material obtained by the above calcination into an alumina pot with 300cc of water, and use an alumina ball to
The powder was pulverized for hours and then dried at 150° C. for 4 hours to obtain a powder of the second additive component.

Note that the proportions of BaO, CaO, and MgO, which are the contents of MO, are k, 20 mol%, 50 mol%, and 30 mol%, as shown in Table 1.

21 Unier primary k, 100 parts by weight (}Ooog) of the basic component k,
As the first additive component, CrzOx and Alz with a purity of 99.0% or more with an average particle size of 0.5μm and well-aligned particles
0.1 parts by weight (1 g) of each of Oz, and 2 parts by weight (20 g) of the second additive component, and then from the water droplet liquid of the acrylic acid ester polymer, glycerin, and condensed phosphate. Add 15% by weight of an organic binder based on the total amount of the basic component and the first and second additive components, add 50% by weight of water, and place these in a ball mill to grind and mix. A slurry of porcelain raw material was prepared.

Next to forming the unfired porcelain sheet, remove the slurry by vacuum. The slurry is put into a reverse roll coater, and the resulting thin film molded product is continuously coated on a long polyester film. was heated to 100° C. and dried to obtain an unsintered porcelain sheet with a thickness of about 25 am. This sheet is long, but
Cut this into 10cm squares and use.

Preparation and printing of conductive paste On the other hand, conductive paste for internal electrodes has an average particle size of 1.5
10g of μm nickel powder and 0.9g of ethyl cellulose
g was concentrated with 9.1 g of butylcarpitol and placed in a stirrer and stirred for 10 hours. Then, 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.

Layering of Unsintered Magnetic Sheets Two unsintered porcelain sheets were laminated with the above-mentioned printed side 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.

After pressing and cutting the waste, this laminate was heated at a temperature of about 50°C for about 40 minutes in the thickness direction.
The laminate was crimped under a load of 1,000 tons, and then the laminate was cut into a lattice shape to obtain 50 laminate chips.

Next to the footwear chip, this laminate chip was placed in a furnace capable of firing in an atmosphere, and heated to 600°C at a rate of 100°C/h in an air atmosphere.
The organic binder was burned by increasing the temperature to .

Thereafter, the atmosphere in the furnace was changed from air to a reducing atmosphere of H2 (2% by volume) and 10N2 (98% by volume). Then, while maintaining the furnace in this reducing atmosphere, the heating temperature of the stacked chips was increased from 600°C to the sintering temperature of 1130°C at a rate of 100°C/h to 1130°C (maximum temperature). After holding for 3 hours, 600℃ at a rate of 100℃/h.
The temperature was lowered to .degree. C., the atmosphere was changed to an air atmosphere (oxidizing atmosphere), 600.degree. C. was maintained for 30 minutes to carry out oxidation treatment, and then cooled to room temperature to obtain a laminated sintered body chip.

Next, zinc, glass frit, and vehicle (
A conductive paste consisting of a vehicle) was applied and dried, and this was baked in the air at a temperature of 550°C for 15 minutes to form a zinc electrode layer, and then a copper layer was further formed on this using an electroless plating method. , and then on top of this, Pb-
A 5N solder layer was provided to form a pair of external electrodes.

As a result, as shown in FIG. 1, the three dielectric ceramic layers 1
2 and two layers of internal electrodes 14.
A multilayer ceramic capacitor 10 was obtained in which a pair of external electrodes 16 were formed on the capacitor 5.

Here, the external electrode 16 includes a zinc electrode N18, a copper layer 20 formed on the zinc electrode layer 18, and a copper layer 20 formed on the zinc electrode layer 18.
and a Pb-5n solder layer 22 formed on top of the Pb-5n solder layer 22.

Note that the dielectric ceramic layer 12 of this multilayer ceramic capacitor 10
The thickness of the dielectric ceramic layer 12 is 0.02 mm, and the opposing area of the pair of internal electrodes 14 is 5 mm x 5 mm = 25 mm.The composition of the dielectric ceramic layer 12 after sintering is determined by mixing the basic components and additive components before sintering. The composition is substantially the same.

I'm in a bad mood.

Next, measure the electrical characteristics of the multilayer ceramic capacitor 10,
The average values were calculated, and as shown in Table 2, k, dielectric constant ε, 3850, tan δ 1.0%, resistivity ρ 6.7X 106 MΩ・cm, based on capacitance at 25°C Rate of change in capacitance △C at -55℃ and +125℃
-55, ΔC125 -9.5%, +3.8%, 20℃
-25℃ based on the capacitance of .

Rate of change in capacitance ΔC-z5 at +85°C. ΔC8, is 4
．． 7%, -5.2%.

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

The relative dielectric constant ε6 of fAl is at a temperature of 20°C and a frequency of 1 kHz.
, the capacitance was measured under the condition of voltage (effective value) 1.0V,
This measurement value and the opposing area of the pair of internal electrodes 14 are 25 mm.
2 and the thickness of the dielectric ceramic layer 12 between the pair of internal electrodes 14 of 0.02 mm.

fB) Dielectric loss tan δ (%) was measured under the same conditions as the above measurement of relative dielectric constant.

The fcl resistivity ρ (MΩ・cm) is determined by applying DC 100V for 1 minute at a temperature of 20°C,
The resistance value between them was measured and calculated based on this measured value and the dimensions.

(D) Temperature characteristics of capacitance: -55°C, -25°C, 0°C, +20°C with the sample placed in a constant temperature bath.

+25℃, +40℃, +60℃, +85℃.

Frequency 1k at each temperature of +105℃ and +125℃
The capacitance was measured under the conditions of Hz and voltage (effective value) lOV, and the rate of change at each temperature with respect to the capacitance at 20°C and 25°C was obtained.

The method for preparing sample No. 001 and its characteristics have been described above, but samples Nos. 2 to 101 also include the composition of the basic component, the first and second additive components, their ratios, and firing in a reducing atmosphere. Except for changing the temperature as shown in Tables 1 and 2, a multilayer ceramic capacitor was prepared in the same manner as the sample No. 1, and its electrical characteristics were measured in the same manner.

Table 1 shows the composition of the basic components and additive components of each sample, and Table 2 shows the firing temperature and electrical characteristics of each sample.

Note that 1-〇 and a in the basic component column of Table 1 are the first basic component elements Bai+-x-zM, Lz) Oi+ (TL 1
-ITRy) 02-2/2 and the second basic component (Barro
The proportion of w) is shown in moles, and k-x-z, x, z,
The ratio of the number of atoms of each element in the compositional formula (1) of the basic components described above is shown.

Mg and Zn in the X column indicate the contents of M in the compositional formula (1) of the basic component mentioned above, the number of atoms of these is shown in these columns, and the number of these atoms is shown in the total column. The total value (X value) is shown.

Ca and Sr in the Z column indicate the contents of the composition formula (1) of the basic components, the numbers of these atoms are shown in these columns, and the total value ( Z value) is shown.

The amount of the additive component added is shown in parts by weight based on 100 parts by weight of the basic component. In the column of MO content of additive ingredients, B
a O, M g O, Z n O, S r O and Ca
The proportion of O is shown in mole %.

In Table 2, the temperature characteristics of capacitance are as follows: △(,,,f%) and △Cog-(%) ), 20
The capacitance change rates at 5°C and +5°C based on the capacitance at °C are shown as Δ(%) and ΔC8,(%).

Table 2 (1) ※marked μ sin hair wounds 7 bite cases Table 2 (2) ※marked; Rito is H" 舊芉Table 2 (3) ※marked Table 2 (4) of 7-bite cases marked with * Marked Table 2 (5) Samples marked with * are from Tables 1 and 2 of comparative examples As is clear, according to the sample according to the present invention, when fired at 1200°C or less in a non-oxidizing atmosphere, the relative dielectric constant ε.

is 3000 or more, dielectric loss tan δ is 2.5% or less,
Resistivity ρ is 1x106MΩ・cm or more, temperature change rate of capacitance ΔC-55 and ΔC1□5 is -15% to +15%
Within the range of temperature change rate of capacitance ΔC-2, and ΔCs
It is possible to obtain a ceramic capacitor having electrical characteristics in which s is in the range of -10% to +10%.

On the other hand, No, 11-16.30,35,40°41
,．． 45, 46.49, 50.55.58-61.66
．． 67.71, 75, 87, 96°97.103 and 1
According to sample No. 04, a ceramic capacitor having desired electrical characteristics could not be obtained. Therefore, these samples are outside the scope of this invention.

Table 2 shows only the temperature change rate of capacitance ΔC-5a, 8C128+ ΔC-2s, and ΔCas, but the temperature change rate of capacitance in the range of -25°C to +85°C of the samples belonging to the scope of the present invention is The temperature change rate ΔC of various capacitances is -10% to
Within the range of +10%, and -55℃ to +125℃
The rate of temperature change ΔC for various capacitances in the range -15%
It falls within the range of ~+15%. - Next, the reason for limiting the composition range of the dielectric ceramic composition used in the ceramic capacitor according to the present invention will be described.

If the value of
-5s is outside the range of 115% to +15%, but X+2
The values of k, o, oi as shown in sample No. 51.52
In this case, a dielectric ceramic composition having desired electrical properties can be obtained. Therefore, the lower limit of the value of X+Z is 0
．． It is 01.

On the other hand, when the value of x+z is k, 0.12 as shown in Sample No. 55.59°60 and 66, ΔC11s is outside the range of -10% to +10%, but the value of X+Z is 5
k, 0 as shown in sample No. 57, 62, 63 and 65
．． In the case of 10, a dielectric ceramic composition having desired electrical properties can be obtained.

However, as shown in sample No. 61, the value of X+Z is k, 0.
Even if Z is 0.06, if the value of Z exceeds 0.05, a dielectric ceramic composition having desired electrical characteristics cannot be obtained.

Therefore, the upper limit of X+Z is 0.10, but at the same time Z
The upper limit of must be 0.05.

In addition, Mg and Zn of the M component and Ca and Sr of the L component work in the same way as f, and Mg and Zn in the range satisfying 2O<x<0.10.
and Zn or both, and O<
One or both of Ca and Sr can be used within a range that satisfies z≦0.05. Then, M component and L
It is desirable that the value of X+Z be in the range of 0.01 to 0.10, regardless of whether one component or several components are used.

If the value of y is k, 0.06 as shown in sample No. 40, a dense sintered body cannot be obtained, but if the value of y is k, 0.04 as shown in sample No. 39, a dense sintered body cannot be obtained. In this case, a dielectric ceramic composition having desired electrical properties can be obtained.

Therefore, the upper limit of y is 0.04.

Note that the R components Sc, Y, Dy, Ho, and Er.

Yb works in the same way as f, and the same result can be obtained even if one selected from them or a plurality of them are used. In any case where there is one type of R component or multiple types of R components, it is desirable that the value of y is in the range of 0.04 or less. Further, if y is 0.04 or less, even a small amount close to 0 will have a certain effect.

In the composition formula, the component represented by R contributes to improving the temperature characteristics of capacitance. That is, by adding the R component, the temperature
Temperature change rate of capacitance ΔC4,, ~△ in the range of 25℃
It becomes possible to easily keep C118 within the range of -15% to +15%, and the temperature change rate of capacitance ΔC-3, ~ΔCss in the range of -25°C to 85°C is -10% ~
It becomes possible to easily keep the capacitance within the 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 R component has the effect of increasing the resistivity ρ and the effect of increasing sinterability.

When the value of a is k, zero as shown in sample No. 41.46, the temperature change rate ΔC-25 of capacitance is -10% to
ΔC-58 is outside the range of +10% and ΔC-58 is outside the range of -15% to +15%, but if the value of α is k, 0.005 as shown in test NNo. 42.47, the desired A dielectric ceramic composition having electrical properties can be obtained. Therefore,
The lower limit value of α is 0.005.

On the other hand, the value of α is k as shown in sample No. 45.49,
In the case of 0.05, the capacitance temperature change rate ΔC86 is outside the range of -10% to +10%, but the value of α is 0.04 as shown in sample No. 44.48. in case of,
A dielectric ceramic composition having desired electrical properties can be obtained. Therefore, the upper limit value of α is 0.04.

When the value of k is smaller than 1.0 as shown in sample No. 67, the resistivity ρ becomes significantly lower than 1×10'MΩ・cm; As shown in No. 68, when k is 1.00, a dielectric ceramic composition having desired electrical characteristics can be obtained. Therefore, the lower limit value of k is 1.00.

On the other hand, the value of k is 1.0 as shown in sample No. 71.
If it is larger than 5, a dense sintered body cannot be obtained, but
When the value of k is 1.05 as shown in Sample No. 70, a dielectric ceramic composition having desired electrical characteristics can be obtained. Therefore, the upper limit of k is l 05.

Croom and/or All0. The added amount of the first additive component consisting of sample No. 96°97.103 and 104
As shown in , if k is more than 3.0 parts by weight, 12
Although a dense sintered body cannot be obtained even if fired at 50°C, sample No.

As shown in 95.102, when k is added in an amount of 3.0 parts by weight, a dielectric ceramic composition having desired electrical properties can be obtained. Therefore, the upper limit of the first additive component is 3.
It is 0 parts by weight.

The first additive component has a certain effect even in a very small amount within a range of 3.0 parts by weight or less.

However, in consideration of variations in electrical properties during mass production, it is desirable to add 0.001 part by weight or more.

Note that the first additive components Cr z Os and Al t O
s works in the same way as 　　, and the same result can be obtained even if one selected from these is used or a plurality of them are used. Whether the first additive component is one type or multiple types, the amount added is desirably within a range of 3.0 parts by weight or less.

This first additive component contributes to improving the temperature characteristics of capacitance. That is, by adding the first additive component, the temperature of -55°C to 1
Temperature change rate of capacitance ΔC-@! in the range of 25℃! 1~
It becomes possible to easily keep ΔC1□ in the range of -15% to +15%, and the temperature change rate of capacitance Δc-Is to ΔCas in the range of -25°C to 85°C can be set to -10% to
It becomes possible to easily keep it within the range of +1.0%,
In addition, 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 slightly increasing the resistivity ρ.

When the amount of the second additive component is zero, sample No. 30
As shown in k, even if the firing temperature is 1250°C, a dense sintered body cannot be obtained, but when the amount added is 0.2 parts by weight per 100 parts by weight of the basic components, sample No. As shown in 31.

A sintered body having desired electrical properties can be obtained by firing at 1200°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. 35, when the amount of the second additive component is 7.0 parts by weight, the dielectric constant ε1 is 300 parts by weight.
However, as shown in sample No. 34, when the amount added is 5.0 parts by weight, it has the desired electrical characteristics. A sintered body is obtained. Therefore, the upper limit of the amount of the second additive component added is 5.0 parts by weight.

A preferred composition of the second additive component is L 120 in FIG.
S i,Oz It can be determined based on a triangular diagram showing the composition ratio of MO.

The first point A in the triangular diagram is L i z O of sample No. 1.
is 1 mol%, SiOz is 80 mol%, MO is 19 mol%, and the second point B is Li of sample No. 2,
0 is 1 mol%, SiO2 is 39 mol%, MO is 60 mol%, and the third point C is the L of sample No. 3.
l20 is 30 mol%, S i Ox is 30 mol%, M
O shows a composition of 40 mol%, and the fourth spot is sample No.
4 Li, 0 is 50 mol%, S i O2 is 50 mol%
, exhibits a composition of 0 mol% MO, and if the fifth point E, sample N
o-5 (7) LiaO is 20 mo JI, %, Sin.

has a composition of 80 mol % and 0 mol % of MO.

The composition of the additive components 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 in this order in the triangular diagram shown in Figure 2. 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, dense sintered bodies cannot be obtained as shown in Sample Nos. 11 to 16.

In addition, MO acid components such as k, B a O, M g O, and Z n O as shown in sample Nos. 17 to 21.

It may be either one of SrO or CaO, or it may be in an appropriate ratio as shown in other samples.

[Effects of the Invention] According to the present invention, since the composition of the dielectric ceramic composition is as described above, the dielectric constant is 3000 or more and the dielectric loss t is
anδ is 2.5% or less, resistivity ρ is lX10'MΩ・c
m or more, and the temperature change rate of the relative permittivity is -55°C
-15% to +15% at ~125℃ (based on 25℃), -
-10% to +10% at 25℃ to 85℃ (based on 20℃)
It is possible to provide a ceramic capacitor with a dielectric ceramic composition falling within the range of .

Further, according to the present invention, in a non-oxidizing atmosphere, 12
Since it can be obtained by firing at a temperature of 00°C or less, it is 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 at the same time. can.

[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 the second additive component. 12...Porcelain layer, 14...Internal electrode, 16...-External electrode.

Claims (1)

[Claims] 1. A ceramic capacitor comprising a dielectric ceramic layer made of a dielectric ceramic composition and at least two or more internal electrodes sandwiching the dielectric ceramic layer, wherein the dielectric ceramic composition contains 100 parts by weight of the basic ingredients and
It is made by baking a mixture of 3.0 parts by weight or less of the first additive component and 0.2 to 5 parts by weight of the second additive component, and the basic component is (1-α) {(Ba_k_-_x_- ＿zM_xL_z
)O_k(Ti_1_-_yR_y}O_2_-_y_
/_2}+αBaZrO_3 (where M is Mg and/or Zn, L is Ca and/or Sr, R is Sc, Y, Gd
, Dy, Ho, Er, Yb, Tb, Tm, one or more metals selected from Lu, α, k, x, z, y
is 0.005≦α≦0.04 1.00≦k≦1.05 0<x<0.10 0<z≦0.05 0.01≦x+z≦0.10 0<y≦0.04 satisfying the above-mentioned first
The additive component consists of Cr_2O_3 and/or Al_2O_3, and the second additive component consists of Li_2O, SiO_2, and MO (However, MO is BaO, SrO, CaO, MgO, and ZnO.
(one or more metal oxides selected from), and the composition range of the Li_2O, the SiO_2, and the MO is such that the Li_2O is 1 mol in the triangular diagram showing these compositions in mol%. %, a first point A having a composition of 80 mol% of the SiO_2 and 19 mol% of the MO, and a composition of 1 mol% of the Li_2O, 39 mol% of the SiO_2, and 60 mol% of the MO. a second point B; a third point C having a composition of 30 mol% of the Li_2O, 30 mol% of the SiO_2, and 40 mol% of the MO; 50 mol% of the Li_2O and 50 mol% of the SiO_2; %, a fourth point D having a composition of 0 mol% of the MO, and a fifth point E having a composition of 20 mol% of the Li_2O, 80 mol% of the SiO_2, and 0 mol% of the MO. A ceramic capacitor characterized by being located within an area surrounded by five straight lines connected in this order. 2. A step of preparing a mixture made of unsintered porcelain powder, a step of forming an unsintered porcelain sheet made of the mixture, and a lamination in which the unsintered porcelain sheet is sandwiched between at least two or more conductive paste films. forming a product, firing the laminate in a non-oxidizing atmosphere, and heat-treating the fired laminate in an oxidizing atmosphere, from the unsintered porcelain powder. The mixture consists of 100 parts by weight of the basic component, 3.0 parts by weight or less of the first added component, and 0.2 to 5 parts by weight of the second added component, and the basic component is (1-α). ((Ba_k_−_x_−_zM_xL_z
)O_k(Ti_1_-_yR_y)O_2_-_y_
/_2}+αBaZrO_3 (However, M is Mg and/or Zn, L is Ca and/or Sr, R is Sc, Y, Gd, Dy, Ho, Er, Yb,
One or more metals selected from Tb, Tm, and Lu, α, k, x, z, and y are 0.005≦α≦0.04 1.00≦k≦1.05 0<x< 0.10 0<z≦0.05 0.01≦x+z≦0.10 0<y≦0.04), and the first
The additive component consists of Cr_2O_3 and/or Al_2O_3, and the second additive component consists of Li_2O, SiO_2, and MO (However, MO is BaO, SrO, CaO, MgO, and ZnO.
(one or more metal oxides selected from), and the composition range of the Li_2O, the SiO_2, and the MO is such that the Li_2O is 1 mol in the triangular diagram showing these compositions in mol%. %, a first point A having a composition of 80 mol% of the SiO_2 and 19 mol% of the MO, and a composition of 1 mol% of the Li_2O, 39 mol% of the SiO_2, and 60 mol% of the MO. a second point B; a third point C having a composition of 30 mol% of the Li_2O, 30 mol% of the SiO_2, and 40 mol% of the MO; 50 mol% of the Li_2O and 50 mol% of the SiO_2; %, a fourth point D having a composition of 0 mol% of the MO, and a fifth point E having a composition of 20 mol% of the Li_2O, 80 mol% of the SiO_2, and 0 mol% of the MO. A method for manufacturing a ceramic capacitor, characterized in that the capacitor is located within an area surrounded by five straight lines connected in this order.