JPH0912361A - Dielectric porcelain composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dielectric porcelain compsn. of a uniform and very small grain diameter ensuring high density of dielectric porcelain. SOLUTION: Niobium oxide as an accessory constituent is incorporated by 0.3-5.0 pts.wt. (expressed in terms of Nb2 O3 ) into 100 pts.wt. principal compsn. contg. <=5mol% Bi2 O3 based on 100mol% compsn. represented by the general formula xBaO.yTiO2 .zR2 O3 , wherein R is one or more kinds of rare earth elements selected from among La, Pr, Nd and Sm, (x), (y) and (z) show molar ratio, x+y+z=1 and (x), (y) and (z) are within the range defined by (a) to (e) in the table.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a ceramic capacitor for electronic equipment and a dielectric ceramic composition used as a dielectric resonator in the microwave region.

[0002]

2. Description of the Related Art A conventional dielectric ceramic composition will be described below. The following systems are known as dielectric porcelain compositions.

[0003] _{BaO · TiO 2 · Nd 2 O} 3 system _{BaO · TiO 2 · Sm 2 O} 3 system _{Bi 2 O 3 · CaO · Nb} 2 O 5 · CuO system e.g. 0.09BaO · 0.56TiO ₂ · 0.35N
Using a dielectric porcelain composition having a composition ratio of dO _3/2 ,
Dielectric porcelain discs were produced, and electrical characteristics, crystal grain size and dielectric porcelain density were measured. Dielectric constant: 67, temperature coefficient of capacitance: N 40 ppm / ° C., Q: 3000, insulation resistance: 8.0 × 10 ¹² Ω, dielectric breakdown strength: ¹² kv / mm
And crystal grain size: 1 to 5 μm, and dielectric ceramic density:
A value of 5.6 g / cm ³ was obtained.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The dielectric ceramic having the above-mentioned structure has a large crystal grain size and a small element density. Then, when Cu plating is performed to form an electrode on the surface of this dielectric ceramic, when etching treatment is performed in an acid solution,
There is a problem in that the mechanical strength of the porcelain and the adhesive strength of the Cu electrode formed on the surface of the porcelain are reduced due to acid etching to the inside of the porcelain, which adversely affects the reliability of the dielectric device.

Therefore, an object of the present invention is to provide a dielectric ceramic composition having a uniform and fine crystal grain size and a high dielectric ceramic density.

[0006]

To achieve this object, the dielectric ceramic composition of the present invention has the general formula xBaO.yT
It is represented by iO ₂ · zR ₂ O _3, where R is La,
One or more rare earth elements selected from Pr, Nd, and Sm, x, y, and z represent a molar ratio, x + y + z = 1, and the values of x, y, and z are a, b, and a shown in (Table 2). c,
Composition 100 mol in the range of molar ratio surrounded by d and e
% Of Bi ₂ O ₃ to 5 mol% or less (however, 0 mo
(excluding 1%) 100 parts by weight of the main component composition contained in the range of 0.3 to 5.0 parts by weight of niobium oxide as a sub-component converted to Nb ₂ O _3. is there.

[0007]

[Table 2]

According to this structure, R in the general formula is La,
By selecting from Pr, Nd, Sm, La, Pr, N
The temperature coefficient of capacitance can be arbitrarily shifted in the positive direction in the order of d and Sm. In addition, by containing niobium oxide in the main component, the sinterability is improved, and the porcelain becomes denser and the crystal grains are made uniform and fine, so that the insulation resistance and the dielectric breakdown strength can be increased and the resonator It is possible to prevent the Q from decreasing.

Further, since the density of porcelain is high, when this dielectric ceramic composition is used to form and mount a multilayer electronic component such as a multilayer ceramic capacitor, it is possible to prevent chip standing, which is usually called the Manhattan phenomenon. it can.

Furthermore, when a dielectric resonator is manufactured using the dielectric ceramic composition of the present invention, the adhesive strength between the dielectric resonator element body and the electrode is high even if the electrode is formed by electroless Cu plating. A highly reliable dielectric resonator can be obtained.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is
As a general formula, xBaO · yTiO_Two・ ZR_TwoO _ThreeRepresented by
R in this general formula is selected from La, Pr, Nd and Sm.
One or more rare earth elements, where x, y and z are
It represents the molar ratio, where x + y + z = 1 and the values of x, y and z are
The molar ratios surrounded by a, b, c, d and e shown in (Table 2)
For the composition 100 mol% in the range, Bi_TwoO_Three5
Included in the range of mol% or less (excluding 0 mol%)
As an auxiliary component to 100 parts by weight of the main component composition
At least niobium oxide_TwoO_FiveConverted to 0.
A dielectric material containing 3 to 5.0 parts by weight.
A porcelain composition, in which the crystal particles are uniformly refined,
High density, insulation resistance, dielectric breakdown strength,
It is possible to prevent the decrease.

The invention described in claim 2 has the general formula x
Represented by _{BaO · yTiO 2 · zR 2 O} 3, the general formula R is, La, Pr, Nd, is one or more rare earth elements selected from Sm, x, y and z represent mole ratios, x
+ Y + z = 1, and the values of x, y, and z shown in (Table 2) are a,
Composition 10 in a molar ratio range surrounded by b, c, d and e
Main component composition 1 containing PbO in an amount of 10 mol% or less (excluding 0 mol%) with respect to 0 mol%
A dielectric porcelain composition, characterized in that at least niobium oxide is contained in an amount of 0.3 to 5.0 parts by weight in terms of Nb ₂ O ₅ as an auxiliary component with respect to 00 parts by weight. The crystal particles are uniformly miniaturized, the porcelain density, the insulation resistance, and the dielectric breakdown strength are large, and the Q of the resonator can be prevented from lowering.

The invention described in claim 3 has the general formula x
Represented by _{BaO · yTiO 2 · zR 2 O} 3, the general formula R is La, Pr, Nd, is one or more rare earth elements selected from Sm, x, y and z represent mole ratios, x +
When y + z = 1, the values of x, y, and z shown in (Table 2) are a, b, and
Composition 100m in the range of molar ratio surrounded by c, d and e
5 mol% or less of Bi ₂ O ₃ with respect to ol% (however, 0
(Excluding mol%) and PbO in the range of 10 mol% or less (excluding 0 mol%) 1
A dielectric porcelain composition, characterized in that at least niobium oxide is contained in an amount of 0.3 to 5.0 parts by weight in terms of Nb ₂ O ₅ as an auxiliary component with respect to 00 parts by weight. The crystal particles are uniformly miniaturized, the porcelain density, the insulation resistance, and the dielectric breakdown strength are large, and the Q of the resonator can be prevented from lowering.

The invention according to claim 4 is the dielectric ceramic composition 100 according to any one of claims 1, 2 and 3.
With respect to parts by weight, Ge, Pb, F, Bi, and
Sb, B, Nb, P, Zn, Si, Al, Mo, W, L
i, Na, K, Ca, Ba, Mg, Ti, Zr, Sn,
In, Gd, La, Ce, Pr, Nd, Sm, Eu, D
y, Yb, Y, Fe, Cr, Mn, Co, Ni, Cu,
20 parts by weight of a low melting point substance or glass component containing at least two kinds selected from Ag and Au (however, 0
(Excluding parts by weight) A dielectric ceramic composition characterized by being added in the following range, which can be sintered at a low temperature of 900 to 1100 ° C.

According to the invention of claim 5, in place of the niobium oxide, tantalum oxide is converted into Ta ₂ O ₅ in an amount of 0.1 to 0.1.
10. The composition according to claim 1, containing 10.0 parts by weight.
The dielectric ceramic composition according to any one of 2, 3, and 4, which has high insulation resistance, dielectric breakdown strength, and Cu electrode adhesion strength.

According to a sixth aspect of the invention, the vanadium oxide is 0.002 in terms of V ₂ O ₅ in place of the niobium oxide.
The dielectric ceramic composition according to any one of claims 1, 2, 3 and 4, wherein the content is 5 to 1.000 parts by weight, the insulation resistance, the dielectric breakdown strength and the Cu electrode. It has a high adhesive strength.

According to a seventh aspect of the invention, in place of the niobium oxide, two or more kinds selected from Nb ₂ O ₅ , Ta ₂ O ₅ and V ₂ O ₅ are added, and Nb ₂ O ₅ is 0.3 to 10. 5.0 parts by weight, Ta ₂ O ₅ is 0.1 to 10.0 parts by weight, V ₂ O ₅ is 0.005 to 1.0
The dielectric ceramic composition according to any one of claims 1, 2, 3 and 4, characterized in that it is contained in a range of parts by weight, the dielectric constant, Q, insulation resistance, and dielectric breakdown. It has a high strength and a small temperature coefficient of positive capacitance.

[0018]

Embodiments of the present invention will be described below.

Example 1 As a starting material, chemically pure BaNb ₂ O ₆ (BaCo ₃ , Nb ₂ O ₅ having a predetermined molar ratio) was used.
Further, it was calcined in advance at a temperature of 1100 ° C. for 3 hours, and then finely ground to an average particle size of 0.5 μm. ), La ₂ O ₃ , P
_{r 6 O 11, Nd 2 O} 3, Sm 2 O 3, TiO 2, Bi 2 O 3, P
The bO and BaCO ₃ powders were weighed so as to have the composition ratios shown in (Table 3), put into a rubber-lined ball mill equipped with agate balls together with pure water, wet-mixed, and dehydrated and dried.

[0020]

[Table 3]

The dried powder was placed in a crucible of high alumina quality and calcined in air at 1100 ° C. for 2 hours. This calcined powder was put into a rubber-lined ball mill equipped with agate balls together with pure water, wet pulverized, and then dehydrated and dried. After adding an organic binder to the pulverized powder to make it homogeneous, 3
The particles were sized through a 2-mesh sieve, and molded into a diameter of 15 mm and a thickness of 0.4 mm at a molding pressure of 1 ton / cm ² using a mold and a hydraulic press. Then, the molded disc is put into an alumina-based sheath coated with zirconia powder, and the disc is put in air at 125
Firing was performed at a firing temperature of 0 to 1450 ° C. for 2 hours to obtain dielectric porcelain having the composition ratio shown in Sample Nos. 1 to 14 of (Table 3).

The thickness, diameter and weight of the dielectric ceramic disk thus obtained were measured, and the weight was divided by the volume calculated from the thickness and diameter to obtain the dielectric ceramic density.

Samples for measuring the dielectric constant, Q, and temperature coefficient of capacitance were printed with silver electrodes on both sides of the dielectric ceramic disk. Samples for measuring insulation resistance and dielectric breakdown strength were prepared on the outer circumference of the dielectric ceramic disk. A portion without a silver electrode having a width of 1 mm was provided inside and the silver electrode was baked. Then, the dielectric constant, Q, and temperature coefficient of capacitance are measured at a measuring temperature of 20 ° C., a measuring voltage of 1.0 Vrms, and a measuring frequency of 1 MHz using a model 4275A of a digital LCR meter manufactured by Yokogawa Hewlett-Packard Co. I asked more. The temperature coefficient of capacitance is 20 ° C.
And the electrostatic capacity at 85 ° C. were measured and determined by the following formula.

TC = (C-Co) / Co × 1/65 × 10 ⁶ TC: Temperature coefficient of capacitance (ppm / ° C.) Co: Capacitance at 20 ° C. (pF) C: Static at 85 ° C. Capacitance (pF) Further, the dielectric constant was obtained from the following equation.

K = 143.8 × Co × t / D ² K: Dielectric constant Co: Capacitance (pF) at 20 ° C. D: Diameter of dielectric ceramic (mm) t: Thickness of dielectric ceramic (mm ) Further, the insulation resistance was measured using Yokogawa Hewlett-Packard Co., Ltd. HR meter model 4329A at a measurement voltage of 50V. D. C. The measurement time was 1 minute.

Regarding the dielectric breakdown strength, a high voltage power source PHS35K-3 type manufactured by Kikusui Electronics Co., Ltd. was used, the sample was put in silicon oil, and the dielectric breakdown voltage was obtained by the step-up speed of 50 V / sec. It was divided by the thickness to obtain the dielectric breakdown strength per 1 mm.

The crystal grain size was determined by observing with an optical microscope at a magnification of 400. The above measurement results are sample numbers 1 to 14
The results are shown separately (Table 4).

[0028]

[Table 4]

FIG. 1 is a ternary diagram showing the composition range of the main components of the composition according to the present invention, and the reason why the composition range of the main components is limited will be described with reference to FIG. That is, it is extremely difficult to sinter in the A region, and the dielectric constant, Q value,
Insulation resistance decreases. Further, in the B region, the Q value decreases and the temperature coefficient of capacitance increases to the negative side, which is not practical. Further, in the C region, the temperature coefficient of capacitance becomes too large on the minus side, which is not practical. Then, in the region D, the temperature coefficient of capacitance shifts in the positive direction, but the dielectric constant is small and it becomes impractical. Also, R is La, Pr,
By selecting from Nd and Sm, La, Pr, Nd and Sm
It is possible to shift the temperature coefficient of capacitance in the positive direction in this order without significantly decreasing the dielectric constant.
The temperature coefficient of capacitance can be arbitrarily adjusted by one or a combination of r, Nd and Sm.

In addition, Bi ₂ O ₃ and PbO are added to the composition range limited to the above, or Nb ₂ O ₅ is further added to the main component containing at the same time to form crystalline particles. Uniform miniaturization and densification are achieved, and it is possible to increase the insulation resistance, the dielectric breakdown strength, and the adhesive strength of the Cu electrode. Further, the conductor loss due to the electrodes is reduced, and the Q of the resonator can be prevented from lowering. Bi
_When the content of ₂ O ₃ or PbO is not present at all or is excessive, a porous porcelain is formed, and the insulation resistance, the dielectric breakdown strength and the Cu electrode adhesion strength are significantly reduced. In addition, by containing the subordinate component Nb ₂ O ₅ which is an essential component with respect to the main component, it has an effect of increasing the insulation resistance, the dielectric breakdown strength and the Cu electrode adhesive strength, and the main content of Nb ₂ O ₅ is If the amount is less than 0.3 parts by weight based on 100 parts by weight of the component, the dielectric breakdown strength and the electrode adhesion strength are not so large, and thus it was excluded from the scope of the present invention. On the other hand, when the content of Nb ₂ O ₅ exceeds 5.0 parts by weight with respect to the main component, Q, the insulation resistance decreases, and the capacitance temperature coefficient increases to the negative side, which is not practical.

The Nb source, which is an essential subcomponent, is Nb ₂ O ₅
Although the starting material may be a starting material, titanium oxide or BaNb ₂ O ₆ , RNbTiO ₆ (R =
La, Pr, Nd, Sm), BiNbO ₄ , Pb ₃ Nb ₄
Use a precursor synthesized with one or more of the main components such as O ₁₃ as a starting material, and use an Nb source with a raw material powder having an average particle size of 0.8 μm or less (maximum particle size distribution of 1.0 μm or less). Is desirable. The reason for this is that compared to when the starting material is Nb ₂ O ₅ , it is more evenly dispersed and solid-solubilized in the ceramics, improving composition homogeneity, and as a result, the sintering reaction proceeds uniformly and abnormal crystal grains occur. This is because grain growth is suppressed and the fine structure is made uniform and fine. Particle size 1.0 μm
When the above Nb source raw material powder is mixed, abnormal grain growth may occur at the time of sintering due to a decrease in composition homogeneity, resulting in a decrease in insulation resistance, dielectric breakdown strength, and Cu electrode adhesion strength.

(Example 2) Sample No. 7 shown in (Table 3) used in Example 1 was used as a basic component, and a low melting point substance or a glass component which becomes a liquid phase at 1100 ° C or less had an average particle size of 0.4 to
Finely pulverized to 0.6 μm (maximum value of particle size distribution is 1.0 μm or less) was added, and treated in the same manner as in Example 1 except that the calcination temperature and the firing temperature were changed to appropriate values (Table 5). The dielectric ceramics shown in sample numbers 15 to 29 shown in FIG.
The characteristics are measured in the same manner as in 1. and the result is sample number 1.
It shows in (Table 6) separately for 5 to 29.

[0033]

[Table 5]

[0034]

[Table 6]

The reason for limiting the composition range and composition of the main component is the same as that of the first embodiment, and therefore its explanation is omitted.

By incorporating a low melting point substance or a glass component into the main component, 11
At a low temperature of 00 ° C. or lower, it is sufficiently wetted to promote sintering, and at the same time, it reacts with the main component composition, so that the firing temperature can be lowered. When the content of the low melting point substance or the glass component exceeds 20 parts by weight with respect to 100 parts by weight of the main component, a secondary phase having a low dielectric constant, a low Q and weak mechanical strength is precipitated, or sintering is inhibited. There is a case. For this reason, the dielectric constant is lowered and the Q value and the adhesive strength of the electrodes are lowered, which makes it impractical. Therefore, it was excluded from the scope of the present invention.

The particle diameters of the low melting point substance and the glass component are
When a material having a large particle size is mixed, it may segregate at the grain boundary portion during sintering, which may adversely affect the mechanical strength and the adhesive strength of the Cu electrode. Therefore, it is desirable that the maximum is 1.0 μm or less.

In this embodiment, sample numbers 15 to 1
8, 20-22, 24, 26-28, other than the low melting point substances and glass components, Ge, Pb, F, Bi, Sb,
B, Nb, P, Zn, Si, Al, Mo, W, Li, N
a, K, Ca, Ba, Mg, Ti, Zr, Sn, In,
Gd, La, Ce, Pr, Nd, Sm, Eu, Dy, Y
900 to 1100 ° C. having the characteristics of the above composition by containing a low melting point substance or a glass component made of at least two kinds selected from b, Y, Fe, Cr, Mn, Co, Ni, Cu, Ag and Au. It is possible to obtain a dielectric ceramic composition that can be sintered at low temperature. Therefore, it is possible to co-fire with high-conductivity electrodes such as low melting point Ag, Ag-Pd, Au, etc., which have excellent high-frequency characteristics, and realize a highly reliable laminated high-frequency dielectric filter and excellent high-frequency characteristics of laminated ceramic capacitors. can do.

(Example 3) High-purity BaNb of Example 1
Instead of ₂ O ₆ , high-purity Ba that was synthesized in the same way in advance was used.
Ta ₂ O ₆ powder was weighed so as to have the composition ratio shown in (Table 7), and the subsequent steps were processed in the same manner as in Example 1 to obtain the dielectric composition having the composition ratio shown in Sample Nos. 30 to 34 of (Table 7). A body porcelain disk was obtained and treated in the same manner as in Example 1 to measure characteristics, and the results are shown in Table 8 for each of sample numbers 30 to 34.

[0040]

[Table 7]

[0041]

[Table 8]

The reason for limiting the composition range and composition of the main component is the same as that of the first embodiment, and therefore its explanation is omitted.

The inclusion of the sub-component Ta ₂ O ₅ with respect to the main component has the effect of increasing the insulation resistance, the dielectric breakdown strength and the Cu electrode adhesion strength, and the content of Ta ₂ O ₅ is 100 wt. If the amount is less than 0.1 parts by weight, the dielectric breakdown strength and the Cu electrode adhesion strength are not so large, and therefore, were excluded from the scope of the present invention. On the other hand, when the content of Ta ₂ O ₅ exceeds 10.0 parts by weight with respect to the main component, Q, insulation resistance and Cu
The electrode adhesion strength decreases, and the capacitance temperature coefficient increases to the negative side, making it impractical. Further, similar effects to those in Example 2 can be obtained even if a low melting point substance or a glass component is contained.

Example 4 High-purity BaNb of Example 1
Instead of ₂ O ₆ , high-purity Ba that was synthesized in the same way in advance was used.
The V ₂ O ₆ powder was weighed so as to have the composition ratio shown in (Table 9), and the subsequent steps were processed in the same manner as in Example 1 to obtain the dielectric composition having the composition ratio shown in Sample Nos. 35 to 39 of (Table 9). A body porcelain disk was obtained, treated in the same manner as in Example 1, and the characteristics were measured. The results are shown in Table 10 for each of sample numbers 35 to 39.

[0045]

[Table 9]

[0046]

[Table 10]

The reason for limiting the composition range and the constitution of the main component is the same as that of the first embodiment, and the explanation thereof will be omitted.

By containing the auxiliary component V ₂ O ₅ with respect to the main component, it has the effect of increasing the insulation resistance, the dielectric breakdown strength and the Cu electrode adhesion strength, and the content of V ₂ O ₅ is the main component 1.
When the amount is less than 0.005 parts by weight with respect to 00 parts by weight, the dielectric breakdown strength and the Cu electrode adhesive strength are not so large, and thus it was excluded from the scope of the present invention. On the other hand, when the content of V ₂ O ₅ exceeds 1.000 parts by weight with respect to the main component, Q, insulation resistance, C
The u-electrode adhesion strength is reduced, making it impractical. Further, similar effects to those in Example 2 can be obtained even if a low melting point substance or a glass component is contained.

Example 5 High-purity BaNb of Example 1
Instead of ₂ O ₆ , high-purity Nb ₂ O ₅ , Ta ₂ O ₅ and V ₂ O ₅ powder finely pulverized to an average particle size of 0.5 μm were weighed so that the composition ratio shown in (Table 11) was obtained. , The subsequent steps in Example 1
The dielectric porcelain discs having the composition ratios shown in Sample Nos. 40 to 44 of Table 11 are obtained in the same manner as in (1), and the characteristics are measured in the same manner as in Example 1 and the results are measured for each of Sample Nos. 40 to 44. It shows in (Table 12).

[0050]

[Table 11]

[0051]

[Table 12]

The reason why the composition range and composition of the main component are limited is the same as in Example 1, and the description thereof is omitted.

With respect to the main component, subcomponents Nb ₂ O ₅ and Ta
By containing ₂ O ₅ and V ₂ O ₅ , it has an effect of increasing insulation resistance, dielectric breakdown strength and Cu electrode adhesive strength,
The content of Nb ₂ O ₅ , Ta ₂ O ₅ and V ₂ O ₅ is the main component,
When the amount is less than the specific amount, the dielectric breakdown strength and the Cu electrode adhesive strength are not so large, and thus it is excluded from the scope of the present invention. on the other hand,
The content of Nb ₂ O ₅ , Ta ₂ O ₅ and V ₂ O ₅ is the main component,
If it exceeds a specific amount, Q and insulation resistance will decrease, and the temperature coefficient of capacitance will increase to the negative side, making it impractical.
_{Further, Nb 2 O 5, Ta 2} O 5, V 2 O by containing two or more selected from _{5, Nb 2 O 5, Ta} 2 O 5, V 2 O 5
The dielectric constant, Q, and
The insulation resistance and breakdown voltage are large, and the temperature coefficient of capacitance can be reduced. Further, similar effects to those in Example 2 can be obtained even if a low melting point substance or a glass component is contained.

The method of manufacturing the dielectric ceramics in the examples
By law, BaNb_TwoO₆, BaTa_TwoO₆, BaV_TwoO₆, V
_TwoO_Five, Ta_TwoO_Five, Nb_TwoO_Five, La_TwoO_Three, Pr₆O₁₁, N
d_TwoO_Three, Sm_TwoO_Three, TiO_Two, And BaCO_ThreeUse
However, the method is not limited to this method, and the desired composition
Ratio of BaTiO3_Three, Bi_TwoTi_ThreeO₉, R _TwoT
i_TwoO₇Compounds such as (R = La, Pr, Nd, Sm),
Or by heating in air such as carbonate, hydroxide,
V_TwoO_Five, Ta_TwoO_Five, Nb_TwoO_Five, La_TwoO_Three, Pr₆O₁₁,
Nd_TwoO_Three, Sm_TwoO_Three, TiO_TwoAnd the combination that becomes BaO
It is possible to obtain the same characteristics as those of the example even if the product is used.
You.

Further, even if the main component is preliminarily calcined and the subcomponents are added, the same characteristics as those of the embodiment can be obtained.

Further, it is generally used for dielectric ceramics.
Titanium dioxide as an industrial raw material, such as Titanium Industry Co., Ltd.
Titanium dioxide KA-10C manufactured by Furukawa Mining Co., Ltd.
Titanium FA-55W has a maximum Nb of 0.45% by weight._TwoO_Five
Examples of using these titanium dioxides
100 weight of the main component even if the dielectric ceramic of the main component of 1 is made
Nb_TwoO_FiveContent of up to 0.2 parts by weight
Yes, it is outside the scope of the present invention.
Nb in titanium_TwoO_FiveInsufficient Nb considering the amount _TwoO_FiveIncluding
To obtain the same characteristics as the embodiment.
Can be.

In addition to the above basic composition, Si
O_Two, MnO_Two, Fe_TwoO_Three, ZnO, Al _TwoO_ThreeEtc. in general
Characteristics of salts and oxides, which are considered to be flux,
Can be added as long as it does not impair.

[0058]

As described above, the dielectric ceramic composition of the present invention is represented by the general formula xBaO.yTiO ₂ .zR ₂ O _3, where R is at least one selected from La, Pr, Nd and Sm. Is a rare earth element, x, y and z represent molar ratios, x + y + z = 1, and the values of x, y and z are (Table 2).
The main component composition containing Bi ₂ O _{3 in an amount} of 5 mol% or less (excluding 0 mol%) with respect to a composition of 100 mol% in a molar ratio range surrounded by a, b, c, d and e shown in In the above general formula, 0.3 to 5.0 parts by weight of niobium oxide is converted into Nb ₂ O ₃ with respect to 100 parts by weight of the compound, and R in the general formula is La, Pr, N
By selecting from d, Sm, La, Pr, Nd, Sm
In this order, the temperature coefficient of capacitance can be arbitrarily shifted in the positive direction.

Further, by containing niobium oxide in the main component, the sinterability is improved, and the crystal grains are made finer with the densification of the porcelain, so that the insulation resistance and the dielectric breakdown strength can be increased. It is possible to prevent the Q of the resonator from decreasing.

Furthermore, since the density of the dielectric ceramic is high, when this dielectric ceramic composition is used to form and mount a multilayer electronic component such as a multilayer ceramic capacitor, chip standing, which is usually called the Manhattan phenomenon, is prevented. be able to.

Further, when a dielectric resonator is manufactured using the dielectric ceramic composition of the present invention, the adhesive strength between the dielectric resonator element body and the electrode is high even if the electrode is formed by electroless Cu plating. Thus, a highly reliable dielectric resonator can be obtained.

Furthermore, the capacitor, the microwave dielectric resonator and the laminated dielectric filter using the dielectric ceramic composition of the present invention largely contribute to the miniaturization and high reliability of electric equipment and communication equipment. It has a great industrial utility value.

[Brief description of the drawings]

FIG. 1 is a ternary diagram illustrating a composition range of main components of a dielectric ceramic composition according to an embodiment of the present invention.

Claims (7)

[Claims] 1. A general formula of xBaO.yTiO ₂ .z
It is represented by R ₂ O _3, where R is La, Pr, N
d, one or more rare earth elements selected from Sm,
x, y and z represent molar ratios, where x + y + z = 1,
For a composition of 100 mol% in which the values of y and z are in the range of molar ratios surrounded by a, b, c, d and e shown in (Table 1),
With respect to 100 parts by weight of the main component composition containing Bi ₂ O _{3 in an amount} of 5 mol% or less (excluding 0 mol%), at least niobium oxide as a sub-component is converted to Nb ₂ O ₅ and converted to 0. A dielectric ceramic composition containing 3 to 5.0 parts by weight. [Table 1] 2. A general formula of xBaO.yTiO ₂ .z
It is represented by R ₂ O _3, where R is La, Pr, N
d, one or more rare earth elements selected from Sm,
x, y and z represent molar ratios, where x + y + z = 1,
For a composition of 100 mol% in which the values of y and z are in the range of molar ratios surrounded by a, b, c, d and e shown in (Table 1),
With respect to 100 parts by weight of the main component composition containing PbO in the range of 10 mol% or less (excluding 0 mol%), at least niobium oxide as an auxiliary component is converted to Nb ₂ O ₅ and the amount is 0.3 to ₅ A dielectric ceramic composition containing 0.0 part by weight. 3. A general formula of xBaO.yTiO ₂ .z
It is represented by R ₂ O _3, where R is La, Pr, N
d, one or more rare earth elements selected from Sm,
x, y and z represent molar ratios, where x + y + z = 1,
For a composition of 100 mol% in which the values of y and z are in the range of molar ratios surrounded by a, b, c, d and e shown in (Table 1),
Bi ₂ O ₃ is 5 mol% or less (however, 0 mol% is excluded) and PbO is 10 mol% or less (however, 0 mol%
% Except 100% by weight of the main component composition contained in the range of at least niobium oxide as an auxiliary component.
A dielectric ceramic composition containing 0.3 to 5.0 parts by weight in terms of ₂ O ₅ . 4. Based on 100 parts by weight of the dielectric ceramic composition according to claim 1, Ge, Pb, F, Bi, Sb, B, Nb, P,
Zn, Si, Al, Mo, W, Li, Na, K, Ca,
Ba, Mg, Ti, Zr, Sn, In, Gd, La, C
e, Pr, Nd, Sm, Eu, Dy, Yb, Y, Fe,
A low melting point substance or glass component consisting of at least two selected from Cr, Mn, Co, Ni, Cu, Ag and Au is added in an amount of 20 parts by weight (excluding 0 parts by weight) or less. A dielectric porcelain composition characterized by: 5. A tantalum oxide is contained in an amount of 0.1 to 10.0 parts by weight in terms of Ta ₂ O ₅ in place of the niobium oxide. 4. The dielectric ceramic composition as described in any one of 4. 6. The method according to claim 1, wherein the vanadium oxide is contained in an amount of 0.005 to 1.000 parts by weight in terms of V ₂ O ₅ in place of the niobium oxide. 4. The dielectric ceramic composition as described in any one of 4. 7. Nb ₂ O ₅ , Ta instead of niobium oxide
Nb ₂ O ₅ has two or more kinds selected from V ₂ O ₅ and V ₂ O ₅ .
3 to 5.0 parts by weight, Ta ₂ O _{5 in an amount} of 0.1 to 10.0 parts by weight, and V ₂ O _{5 in an amount} of 0.005 to 1.0 parts by weight. Item 5. The dielectric ceramic composition according to any one of items 1, 2, 3 and 4.