JPH03278412A - Porcelain capacitor and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve relative permittivity by mixing 100 pts.wt. of specific basic component, and 0.2-5 pts.wt. of 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 and 0.2-5 pts.wt. of additive component containing B2O3, SiO2 and MO (MO is metal oxide of one or more types selected from BaO, SrO, CaO, MgO and ZnO) are mixed and fired. The composition range of the 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 additive component, and hence dielectric porcelain composition having 3000 or more of its relative permittivity can be formed. In formula I, M; Ca and/or Sr, R; one or more types or metal elements selected from Sc, Y, Gd, Dy, Ho, Er, Yb. Letters k, x, z; numerical values for satisfying formulae II, III, IV.

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 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 as a main component is used, 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. be able to. 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 w-x M 1110 m TiO2 (however,
M is a basic component consisting of Mg and/or Zn) and Li-
0 and an additive component consisting of S i Oa are disclosed. In addition, Japanese Patent Publication No. 61-14608 discloses that the dielectric ceramic composition described in Japanese Patent Publication No. 61-14607 is
Instead of i z O and S x Ot, L i *
O, S i Oa and MO (however, %MO is Bad, Ca
A dielectric ceramic composition is disclosed that includes an additive component consisting of one or more metal oxides selected from O and SrO. Also, in Japanese Patent Publication No. 61-14609. (B ai+-x-y Mx LylOIIT i O
*(However, M is Mg and/or Zn, L is Sr and/or Ca), Li2O and Sin
Disclosed is a dielectric ceramic composition comprising an additive component consisting of. Further, in Japanese Patent Publication No. 61-14610, in place of L L 20 and Sin in the dielectric ceramic composition described in Japanese Patent Publication No. 61-14609, L i z
O, S i 02 and MO (However, MO is Bad, Ca
A dielectric ceramic composition is disclosed that includes an additive component consisting of one or more metal oxides selected from O and SrO. In addition, in Japanese Patent Publication No. 61-14611, (Bak
−x Mxloi+ T i Ox (However, M
g. A dielectric ceramic composition comprising a basic component consisting of one or more metal elements selected from Zn*Sr and Ca] and an additive component consisting of B2O3 and Stow is disclosed. In addition, in Japanese Patent Publication No. 1595/1983, (Bait-
n MX) Oi+ T i Ox (However, M is Mg
. One or more metal elements selected from Zn, Sr, and Ca), and B2O3 and MO (
However, MO is Bao. A dielectric ceramic composition containing an additive component consisting of one or more metal oxides selected from M g O, Z n O, S r O, and CaO is disclosed. In addition, Japanese Patent Publication No. 1596/1983 describes the B2O of the dielectric ceramic composition described in Japanese Patent Publication No. 1595/1982.
3 and B2O3 instead of MO. A dielectric ceramic composition is disclosed that includes an additive component consisting of Sin and MO (where MO is Bad. One or more metal oxides selected from MgO, ZnO, SrO, and CaO). . 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 11 from -25°C to +85°C.
It can be in the range of 0% to +10%. [Problems to be solved by the invention] By the way, with the increasing richness of electronic circuits in recent years,
There is a very strong demand for small-sized 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 used in various environments, they are equipped with a dielectric ceramic composition that has a smaller rate of change in relative dielectric constant over a wider temperature range than the dielectric ceramic compositions disclosed in the above-mentioned publications. There was a desire to develop a ceramic capacitor that would Therefore, the object of the present invention is to
Although it can be obtained by firing at temperatures below 200°C, it has a relative dielectric constant of 3000 or more and a dielectric loss tan δ of 2.
．． 5% or less, the resistivity ρ is 1xlO'MΩ・cm or more, and the temperature change rate of the dielectric constant is -15% to +15% (based on 25°C) at -55°C to 125°C, -25°C to 85
An object of the present invention is to provide a ceramic capacitor including a dielectric ceramic composition having a temperature range of -io% to +10% ($1 based on 20°C) and a method for manufacturing the same. [Means for Solving the Problems] A ceramic capacitor according to the present invention includes a dielectric ceramic layer made of a dielectric ceramic composition, and at least two or more internal electrodes sandwiching the dielectric ceramic layer, The dielectric ceramic composition contains 100 parts by weight of basic components and 2O
．． 2 to 5 parts by weight of additional components, and the basic component is (Bak-xMll)O*(T1+-zRz
)Ox-*yz (where M is Ca and/or Sr%R is Sc. 1 selected from Y, Gd, Dy, Ho, Er and Yb
or two or more metal elements, k, x, and z are numeric values satisfying 1 2O0 ≦ k≦ 1 2O5 0 2O1 ≦X≦0 2O5 0, 002 ≦Z ≦0.06), The additive components are B2O3, S i O==, and MO (however, MO is B a O, S r O, Ca O, M g O, and Z
one or more metal oxides selected from nO)
The composition range of the B2O3, the B2O3, and the MO is in the triangular diagram showing these compositions in mol%.
A first composition having a composition of 80 mol % and 19 mol % of the MO.
A second point B having a composition of 1 mol % of the B t Os, 39 mol % of the 5iOz, and 60 mol % of the MO; Oz
a third point C showing a composition in which the MO is 70 mol%; the B2O3 is 90 mol%; the 5iOz is 1 mol%;
a fourth dot having a composition of 9 mol% of the MO; 90 mol% of the B2O3; 9 mol% of the SiO□;
A fifth point E showing a composition of 1 mol% of the MO, and a sixth point F showing a composition of 19 mol% of Mii B2O3, 80 mol% of the 5iOz, and 1 mol% of the MO. This is within the area surrounded by six straight lines connected in sequence. Here, the value of k is preferably in the range of 1.00≦1.05. When the value of k is less than 1.00, the resistivity ρ becomes lXl0
'MΩ・C11, the temperature change rate of capacitance ΔC-5s+ΔC1□5 deviates from -15% to +15%, ΔC-2%+8Cas deviates from -10% to +10%, and k If the value of k exceeds 1.05, a dense sintered body cannot be obtained, but if the value of k exceeds 1.00≦1.05, a dense sintered body cannot be obtained.
This is because within the range of 0.05, a dense sintered body having desired electrical properties can be obtained. Also, the value of X is 0. The range of O1≦X≦0.05 is preferable. If the value of
．． If it exceeds 0.05, the capacitance temperature change rate ΔCC5 will deviate from -10% to +10%, but the value of X will be 0.0
This is because in the range of 1≦X≦0.05, a product having desired electrical characteristics can be obtained. Note that Ca and Sr, which are M components, act in the same manner as f and 2O.
Desired electrical characteristics can be obtained by using one or both of Ca and Sr within a range that satisfies 01≦X≦0.05. Also, the value of Z is 2O. The range of 002≦Z≦0.06 is preferable. When the value of Z is less than 0.002, the capacitance temperature change rate ΔC-65 deviates from -15% to +15%, ΔC-
2. If the value of Z deviates from -10% to +10% and the value of Z exceeds 0.06, a dense sintered body cannot be obtained, but in the range of 0.002≦Z≦0.06, This is because a dense sintered body having desired electrical properties can be obtained. Furthermore, the R component in the compositional formula of the basic components contributes to improving the temperature characteristics of capacitance. That is, by adding the R component, it becomes possible to easily keep the temperature change rate of capacitance ΔC45 to ΔC1□5 in the range of -15% to +15% in the range of -55°C to 125°C, and also It becomes possible to easily keep the temperature change rate of capacitance ΔC-zs to ΔCss in the range of -10% to +lO% in the range of 25°C to 85°C, and to reduce the temperature change rate of capacitance in each temperature range. This makes it possible to reduce the fluctuation range of the temperature change rate. The R component has the effect of increasing the resistivity ρ and the sinterability. Note that the R components Sc, Y, Gd, Dy, and Ho. Er and Yb work in the same way as f, and the same effect can be obtained even if one selected from them is used or a plurality of them are used in combination. However, the value of Z is desirably within the range of 0.002≦Z≦0.06, regardless of whether there is one type of R component or multiple types of R components. In addition, in the compositional formula of the basic components, X and Z naturally indicate the number of atoms of each element. In addition, a trace amount of MnOz (preferably 0.05 to 0.1% by weight) may be added to the basic components within a range that does not impede the purpose of the present invention.
) 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 Bad and SrO. It may also be an oxide or hydroxide such as CaO or other compounds. Next, the amount of the additive component to be added is 20 parts by weight per 100 parts by weight of the basic component. A range of 2 to 5 parts by weight is preferred. If the amount of the additive component added is less than 0.2 parts by weight, a dense sintered body cannot be obtained even if the firing temperature is 1250 ° C.
Furthermore, when the amount of the additive component exceeds 5 parts by weight, the dielectric constant ε8 becomes less than 3000, and the temperature change rate ΔC-5s of capacitance deviates from -15% to +15%, but when the additive component is 0. This is because when the amount is in the range of 2 to 5 parts by weight, desired electrical characteristics can be obtained. The composition of the additive component is preferably within the area surrounded by six straight lines connecting the first to sixth points A to F of the triangular diagram showing the composition ratio of B-0--SiO□-MO in mol%. . If the composition of the additive component is outside this range, a dense sintered body cannot be obtained, but if the composition is within this range, a sintered body with desired electrical properties can be obtained. . Note that the starting materials for the additive components may be other compounds such as oxides and hydroxides. Next, 5, the method for manufacturing a ceramic capacitor according to the present invention includes the steps of preparing a mixture of unsintered porcelain powder consisting of the above-mentioned basic components and additive components, and forming an unsintered porcelain sheet consisting of the mixture. a step of forming a laminate in which the unsintered porcelain sheet is sandwiched between at least two conductive paste films; a step of firing the laminate in a non-oxidizing atmosphere; The method includes a step of heat-treating the laminate in an oxidizing atmosphere. 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 N2 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 600°C in the example, it is not limited to this (it may be any temperature lower than the sintering temperature, preferably in the range of 500°C to 1000°C. The present invention is of course applicable to general single-layer ceramic capacitors other than multilayer ceramic capacitors. [Example] First, the preparation method of sample No. 1 in Table 1 and its electrical properties will be explained. Kibeyo

[The compounds of Vertical 1-Blade Formulation 1 were each weighed and mixed in a 3:00 p.m. ceremony to obtain a raw material mixture. Here, the weight (g) and molar parts of the compound of Formulation 1 are values calculated so that the general formula of the basic components is: Next, this raw material mixture was dried at 150° C. for 4 hours, pulverized, and calcined in the air at a temperature of about 1200° C. for 2 hours to obtain a powder of the basic component. 11 In addition, the compounds of Formulation 2 were each weighed and mixed, 300 cc of alcohol was added to this mixture, and after stirring for 10 hours using an alumina ball in a polyethylene pot, the mixture was heated to a temperature of 1000°C in the atmosphere. It was pre-baked for 2 hours. Here, the weight (g) and molar parts of the compound of formulation 2 are B2
O3 is 1 mol%, SiO□ is 80 mol%, MO is 19 mol% (BaO (3°8 mol%) + CaO (3.8 mol%) + SrO (3.8 mol%) +
This value was calculated so that the composition would be MgO (3.8 mol%) + ZnO (3.8 mol%). Next, the material obtained by this calcining was placed in an alumina pot with 300 cc of water, and an alumina ball was used to
Grind for hours, then dry at 150°C for 4 hours,
A powder of additive components was obtained. In addition, the contents of MO are Bad and Cab. As shown in Table 1, the proportions of SrO, MgO and ZnO are all 20 mol%. 2522 momme] 1 Next, to 100 parts by weight (1000 g) of the above basic component, 2 parts by weight (20 g) of the above additive components were added, and an aqueous solution of acrylic acid ester polymer glycerin and condensed phosphate was added. An organic binder consisting of 15% by weight is added based on the total weight of the basic components and additive components, and
0% by weight of water was added, and these were placed in a ball mill to be ground and mixed to prepare a slurry of porcelain raw materials. Formation of an unsintered porcelain sheet Next, the above slurry is put into a vacuum defoaming machine to be defoamed, 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. The receiver was removed and dried on the same film by heating at 100° C. to obtain an unsintered porcelain sheet with a thickness of about 25 LLm. This sheet is long, but it is
Cut into 0 cm squares and use. Preparation and printing of conductive paste On the other hand, the 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 dissolved in 9.1 g of butylcarpitol were 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 each having a length of 14 mm and a width of 7 mm, and then dried. Layer of Magnetic 1 Sheet Next, two unsintered porcelain sheets were laminated with the 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. Further, four unsintered porcelain sheets each having a thickness of 60 μm were laminated on the upper and lower surfaces of this laminate. After applying pressure to the μ material, the laminate was heated approximately 4 mm in the thickness direction at a temperature of approximately 50°C.
A load of 0 tons was applied to bond the parts. Thereafter, this laminate was cut into a grid shape to obtain 50 laminate chips. Next to the chip, this laminate chip is placed in a furnace capable of atmosphere firing, and heated to 600°C at a rate of 100°C/h in an atmospheric atmosphere.
The organic binder was burned. After that, the atmosphere of the furnace was changed from the atmosphere to H2 (2% by volume) + N.
, (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 1150°C.
Raise the temperature at a rate of 100°C/h to 1150°C (maximum temperature)
After holding for 3 hours, the temperature was lowered to 600°C at a rate of 100°C/h, the atmosphere was changed to an air atmosphere (oxidizing atmosphere), and 600°C was held for 30 minutes to perform oxidation treatment.
Thereafter, it was cooled to room temperature to obtain a laminated sintered body chip. Outside! ! very! 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 laminated ceramic capacitor lO was obtained in which a pair of external electrodes 16 were formed on the laminate 5. Here, the external electrode 16 includes a zinc electrode layer 18, 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.Electricity 1 Next, the electrical characteristics of the multilayer ceramic capacitor 10 are measured,
The average values were calculated, and as shown in Table 2, the relative dielectric constant ε is 3530, tan δ is 1.2%, resistivity ρ is 4.8XIO'MΩ・cm, and the capacitance at 25°C is Rate of change in capacitance ΔC- at -55℃ and +125℃ based on standard
6゜ΔC1□ is -11.4%, +6.3%, and the rate of change in capacitance at -25℃ and +85℃ based on the capacitance at 20℃ is C-25+ ΔC115 is -7.1 %. -5.2%. Note that the electrical characteristics were measured in the following manner. The relative dielectric constant ε8 of f'Al is at a temperature of 20°C and a frequency of 1kHz.
, voltage (effective value) 1. Measure the capacitance under OV conditions,
This measurement value and the opposing area of the pair of internal electrodes 14 are 25 mm.
2 and the fBl dielectric loss tan δ (%) calculated from the thickness of 0.02 mm of the dielectric ceramic layer 12 between the pair of internal electrodes 14 was measured under the same conditions as the above-mentioned measurement of the dielectric constant. fcl resistance resistivity (Ω cm) is the difference between the pair of external electrodes 16 after applying DClooV 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. The temperature characteristics of +01 capacitance are as follows: -55°C, -25°C, 20°C, +20°C when the sample is placed in a constant temperature bath. +25℃, +40℃, +60℃, +85℃. Frequency 1 at each temperature of +105℃ and +125℃
The capacitance was measured under the conditions of kHz and a voltage (effective value) of 1.0 V, and the rate of change at each temperature with respect to the capacitance at 20° C. and 25° C. was obtained. The preparation method of samples No. 1 and their characteristics have been described above, but for samples No. 32 to 81, the compositions of the basic components and additive components, their ratios, and the firing temperature in a reducing atmosphere are shown in Table 1. A multilayer ceramic capacitor was prepared in exactly the same manner as the sample N011, except for the changes shown in Table 2, and the 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 properties of each sample. Note that x and z in the basic component column of Table 1 are the number of atoms of each element in the composition formula (1) of the basic component described above, that is, (
The ratio of the number of atoms of each element is shown when the number of atoms of Ti+R) is 1. In addition, Ca and Sr in the column X indicate the contents of M in the basic component composition formula (1) described above, and Sc, Y, Gd in the column 2,
Dy, Ho, Er, and Yb indicate the content of R in the basic component composition formula (1) described above. The numbers of these atoms are shown in these columns, and the total values of Ca and Sr are shown in the total column. The amount of the additive component added is shown in parts by weight based on 100 parts by weight of the basic component. B in the column of MO content of additive ingredients.
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: ΔC-5-(%) and ΔC1□5 (%) So, 2
The capacitance change rate at -25℃ and +85℃ based on the capacitance at 0"C is △(,,, (%) and ΔCs5 (%)
is shown. Table 2 (1) *Marked t-fin Table 2 (2) *Marked ντ1 [7bite cases Table 2 (3) *Marked M-Fin combination No. 2 Table (4) The relative dielectric constant ε is 3000 or more, and the tan δ is 2.
5% or less, resistivity ρ is l×10'MΩ・cm or more, temperature change rate of capacitance is 〇-5, and ΔC1□ is -15%.
~ +15%, ΔC-25 and △CaS -10% ~ +1
0% range, making it possible to obtain a ceramic capacitor with desired characteristics. On the other hand, sample No. 11-13, 26, 31°32.40
~45,49.50,55.56゜62.63.69,
80.81 cannot achieve the purpose of the present invention. Therefore, these are outside the scope of the present invention. Table 2 shows the temperature change rate of capacitance ΔC-m5+ΔCIx
Although only sr △C-zs+ ΔC□ is shown, the temperature change rate ΔC of various capacitances in the range of 25°C to +85°C is -10% to +lO
%, and the rate of change of various capacitances ΔC in the range of -55°C to +125°C is -15% to +15%.
is within the range. Next, the reasons for limiting the composition range of the dielectric ceramic composition of the present invention will be described. First, when the value of X is zero as shown in sample No. 32, the temperature change rate ΔC-6 of capacitance is 115%
Although it is outside the range of +15%, desired electrical characteristics can be obtained when the value of %X is 0.01 as shown in sample No. 33.34. Therefore, the lower limit of X is 0.01. On the other hand, as shown in sample Nos. 40 to 44, the value of X is 0.
．． In the case of Sample No. 38.06, the temperature change rate ΔCas of capacitance is outside the range of -10% to +10%.
As shown in 39, when the value of X is 0.05, desired electrical characteristics can be obtained. Therefore, the upper limit of X is 0
．． It is 05. Note that Ca and Sr, which are M components, act in the same manner as f and 2O.
Desired electrical characteristics can be obtained by using one or both of Ca and Sr within a range that satisfies 01≦X≦0.05. As shown in sample No. 45, when the value of k is 0.98, ρ is 1. It is significantly lower than XlO'MΩ・C11, and the temperature change rate of capacitance ΔC-5s+ ΔC-2
, and 15% each. Although it is significantly worse than -10%, sample No. 46
As shown in the figure, when the value of 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, the value of k is 1.0 as shown in sample No. 49.
In the case of sample No. 7, a dense sintered body cannot be obtained, but in the case of sample No.
As shown in 48, 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
It is. The value of Z is 2 as shown in sample No. 50.56.63.
In the case of O, the temperature change rate of capacitance △C-5, ΔC-2
, are 15% each. Sample No. does not satisfy -10% or less. As shown in 51 57.64, when the value of Z is 0.002, desired electrical characteristics can be obtained. Therefore, the lower limit of 2 is 0.002. On the other hand, the value of Z is sample No. 55.62.69°80.8
As shown in 1, 2O. In the case of sample No. 54.07, a dense sintered body could not be obtained even if fired at 1250°C.
As shown in 61.68 and 78.79, when the value is 0.06, desired electrical characteristics can be obtained. Therefore, the upper limit of the value of 2 is 0.06. Note that the R components are Sc, Y, Gd, Dy, and Ho. Er and Yb work in the same way as f, and the same result can be obtained even if one selected from them is used or a plurality of them are used in combination. It is desirable that the value of 2 is in the range of 0.002 to 0.06, regardless of whether there is one type of R component or multiple types of R components. The component represented by R in the compositional formula contributes to improving the temperature characteristics of capacitance. That is, by adding the R component, the temperature change rate ΔC of capacitance in the range of -55°C to 125°C, SS to ΔC12, is increased by -15% to +15%.
It becomes possible to easily keep the temperature within the range of -25℃.
Temperature change rate of capacitance ΔC-25 in the range of ~85℃
It becomes possible to easily keep ΔC85 within the range of -10% to +10%, and it is possible to reduce the range of variation in the temperature change rate of capacitance in each temperature range. Moreover, the R component has the effect of increasing the resistivity ρ and the effect of increasing the sinterability. In addition, when the amount of additive components added is zero, sample N092
As is clear from No. 6, even if the firing temperature is 1250°C, a dense sintered body cannot be obtained. However, as shown in sample No. 27, the addition amount is 0.00% per 100 parts by weight of the basic components.
In the case of 2 parts by weight, desired electrical properties can be obtained by firing at 1190°C. Therefore, the lower limit of the additive component is 0.2 part by weight. On the other hand, as shown in sample No. 31, when the amount of the additive component is 7.0 parts by weight, the relative dielectric constant ε8 is less than 3000, and the temperature change rate ΔC-m5 of capacitance is Although it is outside the range of 15% to +15%, as shown in sample No. 30, when the amount added is 5.0 parts by weight, desired electrical characteristics can be obtained. Therefore, the upper limit of the amount added is 5.0 parts by weight. The preferred composition of the additive components is B203-3 i in Figure 2.
It can be determined based on a triangular diagram showing the composition ratio of O and -MO. The first voice in the triangular diagram, A, is sample No. 1, and B2O3 of 1 is 1.
mol%, 5iO- shows a composition of 80 mol%, MO shows a composition of 19 mol%, and the second point B shows that 82O3 of sample No. 2 is 1
mol%, SiO2 is 39 mol%, MO is 60 mol%, and the third point C is that B2O3 of sample No. 3 is 2
9 mol%, SiO2 is 1 mol%, MO is 70 mol%.
mol%, Sin, shows a composition of 1 mol%, MO is 9 mol%, and the fifth point E has sample No. 5 with 90 mol% of B2O3, 9 mol% of SiOt, and 1 mol of MO. % composition, and the sixth point F is sample No. 6 with B2O3 of 19
The composition is 80 mol% of 5iO- and 1 mol% of MO. The composition of the additive components of the sample that falls within the scope of the present invention is within the region surrounded by six straight lines connecting the first to sixth points A to F of the triangular diagram in order. If the composition is within this region,
Desired electrical characteristics can be obtained. On the other hand, if the composition of the additive components falls outside the range specified in the present invention, as in Samples Nos. 11 to 13, a dense sintered body cannot be obtained. In addition, MO acid components such as BaO, MgO, and ZnO as shown in Sample Nos. 14 to 18. It may be any one of S r Or Ca O, or 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 lX1O'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 additive components. 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 firing a mixture with 0.2 to 5 parts by weight of additional components, and the basic component is (Ba_k_-_xM_x)O_k(Ti_1_-_z
R_z) O_2_-_z_/_2 (where M is Ca and/or Sr, R is one or more metal elements selected from Sc, Y, Gd, Dy, Ho, Er, and Yb,
k, x, and z are made of substances expressed by numerical values satisfying 1.00≦k≦1.05, 0.01≦x≦0.05, 0.002≦z≦0.06, and the additive component is B_2O_3 , SiO_2, and MO (where MO is one or more metal oxides selected from BaO, SrO, CaO, MgO, and ZnO), and the composition range of the B_2O_3, the SiO_2, and the MO is , in a triangular diagram showing these compositions in mol%, a first point A indicating a composition of 1 mol% of the B_2O_3, 80 mol% of the SiO_2, and 19 mol% of the MO; and 1 mol% of the B_2O_3. , a second point B having a composition of 39 mol% of the SiO_2 and 60 mol% of the MO; and a second point B having a composition of 29 mol% of the B_2O_3, 1 mol% of the SiO_2, and 70 mol% of the MO. 3 point C, and a fourth point D showing a composition of 90 mol% of B_2O_3, 1 mol% of SiO_2, and 9 mol% of MO; and 90 mol% of B_2O_3 and 9 mol% of SiO_2. , a fifth point E in which the MO has a composition of 1 mol %, the B_2O_3 is 19 mol %, and the SiO_2 is 80 mol %.
mol %, and the MO is located within a region surrounded by six straight lines connecting in this order a sixth point F showing a composition of 1 mol %. 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 and 0.2 to 5 parts by weight of additional components, and the basic component is (Ba_k_-_xM_x)O_k(Ti_1_-_z
R_z) O_2_-_z_/_2 (where M is Ca and/or Sr, R is one or more metal elements selected from Sc, Y, Gd, Dy, Ho, Er, and Yb,
k, x, and z are made of substances expressed by numerical values satisfying 1.00≦k≦1.05, 0.01≦x≦0.05, 0.002≦z≦0.06, and the additive component is B_2O_3 , SiO_2, and MO (where MO is one or more metal oxides selected from BaO, SrO, CaO, MgO, and ZnO), and the composition range of the B_2O_3, the SiO_2, and the MO is , in a triangular diagram showing these compositions in mol%, a first point A indicating a composition of 1 mol% of the B_2O_3, 80 mol% of the SiO_2, and 19 mol% of the MO; and 1 mol% of the B_2O_3. , a second point B having a composition of 39 mol% of the SiO_2 and 60 mol% of the MO; and a second point B having a composition of 29 mol% of the B_2O_3, 1 mol% of the SiO_2, and 70 mol% of the MO. 3 point C, and a fourth point D showing a composition of 90 mol% of B_2O_3, 1 mol% of SiO_2, and 9 mol% of MO; and 90 mol% of B_2O_3 and 9 mol% of SiO_2. , a fifth point E in which the MO has a composition of 1 mol %, the B_2O_3 is 19 mol %, and the SiO_2 is 80 mol %.
A method for manufacturing a ceramic capacitor, characterized in that the MO is located within an area surrounded by six straight lines connecting in this order to a sixth point F showing a composition of 1 mol %.