JP2002193667A - Dielectric ceramic and stacked electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric ceramic whose dielectric constant is high and whose temperature characteristics of the dielectric constant is good even if crystal particles are made to be fine particles and to provide a stacked electronic part whose reduction rate of electrostatic capacity is low even when a high voltage is applied by the dielectric ceramic. SOLUTION: The dielectric ceramic comprises a perovskite BTZ crystal particles which include at least one of Ba, Ti, Zr, Mg, Y, Er, and Yb as metal elements and perovskite BT crystal particles which include at least one of Ba, Ti, Mg, Y, Er, and Yb as metal elements, and these perovskite crystal particles have a core-shell structures, and the mean particle diameter is 0.3 to 1.0 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric ceramic and a multilayer electronic component, for example, a high-voltage multilayer ceramic capacitor in which a DC voltage applied to a dielectric layer is 2 V / .mu.m or more. The present invention relates to a dielectric porcelain and a laminated electronic component used for the like.

[0002]

2. Description of the Related Art In recent years, with the miniaturization and high performance of electronic devices, demands for miniaturization and large capacity of multilayer ceramic capacitors have been increasing. To meet such demands, multilayer ceramic capacitors (MLCs)
The capacitance is increased by reducing the thickness of the dielectric layer, and the size and the capacitance are increased by increasing the number of layers.

[0003] In order to reduce the size and capacity of the dielectric material,
Various characteristics are required, such as low dielectric loss, good temperature characteristics, and low dependence of the dielectric characteristics on the DC voltage, as well as a high dielectric constant.

Further, as the thickness of the multilayer ceramic capacitor is reduced, the size of particles is reduced in order to suppress a decrease in reliability due to an increase in an electric field applied to the multilayer ceramic capacitor.

It is known that the relative permittivity of barium titanate (BaTiO ₃ , also referred to as BT) as a conventional dielectric material depends on the particle diameter.
At μm, the relative permittivity shows the maximum value, and when the particle size is further reduced, the relative permittivity monotonously decreases. Currently, multilayer ceramic capacitors (ML) with small size, high capacitance and excellent temperature characteristics
C) The material is a BT-based material, and uses a sintered body having a submicron particle size and a large relative dielectric constant.

As a dielectric ceramic having good temperature characteristics, a BT-based material of a particle called a core-shell structure (having a different composition between a central portion and a peripheral portion) containing a small amount of zirconia or the like is known. Due to the effect of suppressing grain growth and the core-shell structure, a dielectric ceramic having good temperature characteristics has been manufactured.

[0007]

However, the BT material has a large decrease in the relative dielectric constant due to the application of a DC voltage,
When the thickness is reduced for miniaturization, the electric field applied to the BT-based material increases, so that there is a problem that the capacitance is largely reduced and the effective capacitance is reduced. For this reason, in MLC using BT, there was a limit in thinning.

[0008] When the particle size of BT is made smaller than submicron, the DC bias dependency can be improved, but the relative dielectric constant also decreases.
The C bias dependency could not be satisfied at the same time.

For the purpose of improving the DC bias dependency, a dielectric ceramic as disclosed in Japanese Patent Application Laid-Open No. 9-241075 has been conventionally known. In this publication,
The average particle diameter of the particles constituting the dielectric porcelain is 0.1 to 0.3.
It is described that a flat temperature characteristic and an excellent DC bias characteristic can be realized by miniaturization to μm and forming the dielectric ceramic by two or more kinds of fine particle crystals having different temperature characteristics.

Further, according to this publication, it is difficult to form a core-shell structure for realizing flat temperature characteristics and excellent DC bias characteristics with a particle size of 1 μm or less.
In order to obtain the same effect with a particle size of 1 μm or less, finer particles are further formed to reduce the dielectric activity of the dielectric ceramic, thereby obtaining flat temperature characteristics and excellent DC bias characteristics.

However, as described above, the relative dielectric constant monotonously decreases with the particle size.
At a particle size such as μm, a relative dielectric constant of only about 2100 was obtained at the maximum, and there was a limit to increasing the capacity.

When the particle size of the raw material is 0.3 μm or less, a solid solution is easily formed at the time of sintering and the particles grow, so that it is necessary to produce a dense sintered body while maintaining the raw material particle size. Various conditions were required, and fabrication was difficult.

Accordingly, the present invention provides a dielectric porcelain having a large relative dielectric constant and good relative dielectric constant temperature characteristics even when the crystal grains are finely divided, so that even when a high voltage is applied, the dielectric porcelain can be statically charged. It is an object of the present invention to provide a dielectric porcelain and a multilayer electronic component having a small capacity reduction rate.

[0014]

The inventor of the present invention has studied the above problems, and as a result, has found that a BT material exhibiting a large relative dielectric constant and excellent in temperature characteristics and a large Ba (Ti _1-x Zr _x ) O, which shows a temperature characteristic of the relative permittivity and a flat DC bias characteristic.
₃ (hereinafter also referred to as BTZ) has a large relative dielectric constant by forming a coexisting structure with a submicron size and forming a core-shell structure in each particle, and has a flat temperature characteristic and The present inventors have found that a dielectric ceramic excellent in DC bias characteristics can be realized, and have reached the present invention.

That is, the dielectric porcelain of the present invention is a perovskite type B containing Ba, Ti, Zr, Mg as a metal element and at least one of Y, Er and Yb.
TZ crystal particles, Ba, Ti, Mg as metal elements,
A perovskite-type BT crystal particle containing at least one of Y, Er and Yb;
The Z crystal particles and the BT crystal particles have a core-shell structure, and have an average particle size of 0.3 to 1.0 μm.

In general, BT exhibits a large relative dielectric constant exceeding 4000 due to an increase in atomic fluctuations accompanying the successive phase transition, but has a high relative dielectric constant due to the successive phase transition, and therefore, BT has a high relative dielectric constant.
The application of an external field such as a bias greatly reduces the relative dielectric constant.

On the other hand, in BTZ, the peak of the sequential phase transition observed in BT converges to one point, and is broad (flat) and has a large relative dielectric constant. When the particle size of the BTZ is 1 μm or less, the fluctuation of atoms due to the phase transition is reduced, and only the peak value decreases while the relative dielectric constant maintains a large value as a whole, showing a flat temperature characteristic.

This is because the dielectric activity associated with the phase transition is reduced and the polarization characteristics of the atoms are in a dielectric ground state close to that of a paraelectric, so that the peak of the relative dielectric constant is reduced and a broader temperature characteristic is obtained. It is because it becomes. This reduces the dependence on an external field such as a DC bias. Also, BTZ
When compared with the same particle size, the fine particles have a higher dielectric constant than BT and have less DC bias dependency.

That is, the dielectric porcelain of the present invention has a coexistence structure of a BT crystal particle having a high relative dielectric constant and excellent in temperature characteristics and a BTZ crystal particle having a relatively high dielectric constant and excellent DC bias characteristics. By realizing the dielectric material, a dielectric material having a high dielectric constant, flat temperature characteristics, and excellent DC bias characteristics can be realized.

Further, since the BT crystal particles and the BTZ crystal particles have a core-shell structure, the peak of the relative dielectric constant becomes broader, and the temperature characteristics and the DC bias characteristics can be further improved.

Further, in the BTZ crystal grains of the dielectric ceramic of the present invention, it is desirable that a part of the B site is substituted with 5 to 30 mol% of Zr. Within this range, BT
When the broad peak of the relative permittivity of the Z crystal particles is near room temperature and a composite structure is formed with the BT crystal particles, a large capacitance can be secured in a temperature range used as a capacitor.

Further, the dielectric porcelain of the present invention comprises Ca and / or Mn as metal elements, CaCO ₃ , MnCO ₃
It is desirable to contain each 0.4% by weight or less in conversion. These metal elements enable porcelain densification while suppressing grain growth of BT and BTZ crystals during sintering, and BT and BTZ having a structure composed of fine crystals even in normal firing without pressurization. A sintered body can be easily manufactured. Also,
These elements partially diffuse into the particles to form a core-shell structure.

The laminated electronic component of the present invention is a laminated electronic component in which dielectric layers and internal electrodes made of a base metal are alternately laminated, wherein the dielectric layer is made of the above-mentioned dielectric ceramic. It is. The BT according to the present invention, which has a large relative dielectric constant, good dielectric constant temperature characteristics, and excellent DC bias characteristics.
-By using the BTZ composite dielectric porcelain for the dielectric layer, a large-capacity multilayer capacitor can be obtained without increasing the number of layers by reducing the thickness.

Further, since the crystal grain size is small, it is easy to make the dielectric layer thinner, and it is possible to further improve the capacitance and further reduce the size. Further, by using a base metal as an internal electrode, an inexpensive laminated electronic component can be obtained.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The dielectric porcelain of the present invention comprises Ba, Ti, Zr, Mg as metal elements, Y, Er and Yb.
A perovskite-type BTZ crystal particle containing at least one of Ba, Ti, and Mg as metal elements.
And perovskite-type BT crystal particles containing at least one of Y, Er and Yb,
The Z crystal particles and the BT crystal particles have a core-shell structure, and have an average particle size of 0.3 to 1.0 μm.

The reason why the average particle diameter of the BTZ crystal particles and the BT crystal particles is 0.3 to 1.0 μm is that the average particle diameter is 0.1 μm.
If it is smaller than 3 μm, the relative dielectric constant of both BT and BTZ is small. In addition, solid solution easily occurs between the two, and it is difficult to realize a coexisting structure.
When the average particle size is larger than 1.0 μm, BT
This is because the relative permittivity monotonously decreases with the grain size in the crystal grains, and the relative permittivity in the BTZ crystal grains increases in proportion to the grain size, but exceeds 1 μm. This is because temperature characteristics are greatly deteriorated. The average particle size of the BTZ crystal particles and the BT crystal particles is desirably 0.4 to 0.8 μm from the viewpoint of improvement in relative dielectric constant and stability of temperature characteristics.

In the dielectric porcelain of the present invention, the BTZ crystal particles and the BT crystal particles have a core-shell structure, and each particle has a different composition in the central portion and the peripheral portion.

In the present invention, the reason why the BTZ crystal particles and the BT crystal particles exhibit a core-shell structure is as follows.

BTZ particles are liable to undergo grain growth due to atomic diffusion during sintering, and it is difficult to obtain a dense sintered body having a small particle size. In a sintered body of a mixture of BT and BTZ,
Since BT has a lower sintering temperature than BTZ, BT promotes solid solution between the two and easily forms a solid solution. If the particle size is smaller than submicron, the surface area occupies a large proportion of the particle volume, and the surface energy is large, so that it becomes unstable in terms of energy. Stabilizes by lowering.

For this reason, grain growth tends to occur, and it is difficult to obtain a dense sintered body composed of fine particles. Especially 0.3μ
A sintered body of BT and BTZ having a small particle size smaller than m easily causes solid solution and grain growth, and a large particle size exceeding 1 μm unless a material that suppresses the movement of atoms between particles is introduced between particles. , And it is difficult to obtain a dense sintered body having a fine particle size of submicron or less.

On the other hand, by introducing a rare earth element such as Mg and Y as an additive together with the fine crystal raw material, and further adjusting the firing conditions, a fine particle sintered body reflecting the size of the raw material crystal particles is obtained. Can do things. These additives promote sintering together with Mn and glass by diffusing to the particle surface to form a liquid phase, and also Ba and Ti between BT and BTZ which are near and at the grain boundaries and are the parent phase. ,
It suppresses the movement of Zr atoms and suppresses grain growth. As a result, a crystal phase in which the additive is diffused and dissolved in the particle surface is formed.

As described above, the particle size of BT and BTZ is increased to submicron, specifically, 0.3 μm or more.
BTZ and BT which are easy to form a solid solution and easily grow grains by adjusting the sintering conditions by introducing an additive which suppresses solid solution.
Can be produced.

In the dielectric porcelain of the present invention, it is desirable that a part of the B site of the BTZ crystal particles is substituted with 5 to 30 mol% of Zr. Within this range, BTZ
When the broad peak of the relative permittivity of the crystal particles is near room temperature and a composite structure is formed with the BT crystal particles, a large capacitance can be secured in a temperature range used as a capacitor.

When the amount of B site substituted by Zr is less than 5 mol%, the dielectric properties of BTZ are not much different from BT, and the effectiveness of forming a composite structure of BTZ and BT is small. On the other hand, if it is more than 30 mol%, the peak temperature of the relative dielectric constant is too low, so that a sufficient relative dielectric constant cannot be obtained in the operating temperature range of the capacitor. Also, when the amount of Zr is large, the value of the relative dielectric constant becomes small, and a sufficient relative dielectric constant cannot be obtained. BT
The replacement amount of the B site by Zr in the Z crystal particles is preferably 5 to 20 mol% from the viewpoint of the relative dielectric constant, the peak temperature, and the peak broadness.

Further, the dielectric porcelain of the present invention is characterized in that at least one of Ca and Mn is used as a metal element and CaCO ₃ , M
It is desirable to contain each in a ratio of 0.4% by weight or less in terms of nCO ₃ . These metal components increase the electrical insulation of the dielectric porcelain, increase the high-temperature load life, and enhance the reliability. If the amount is more than 0.4% by weight, the insulating property decreases.

The dielectric porcelain of the present invention comprises BT crystal particles and B
Consisting of TZ crystal particles, Mg, Y, Er, Yb
One of them is almost completely dissolved in the BT crystal particles and the BTZ crystal particles, but may be partially present at the grain boundaries. When it exists at the grain boundary, it mainly exists as amorphous.

In the BT crystal particles and BTZ crystal particles, Ba, Ti, and Zr are uniformly present, and Mg,
One of Y, Er and Yb is mainly BT crystal particles, BT
It is present at the outer periphery of the Z crystal grain, and has a core-shell structure having different compositions at the center and the periphery of the crystal grain.

Further, Ca and Mn to be added are dissolved in BT crystal particles or BTZ crystal particles or exist as amorphous mainly at grain boundaries.

In order to manufacture the dielectric porcelain of the present invention, for example, a sol-gel method, an oxalic acid method, and a hydrothermal synthesis method are used.
BT having a predetermined composition and an average particle size of 0.1 to 1 μm
Z powder and BT powder are used.

Further, a predetermined amount of an oxide or carbonate of a metal element such as Mg, Ca, Mn, Y, Er, or Yb is added to the BTZ and the BT powder, and the powder is added with a rotary mill or the like.
After wet mixing for 8 hours and drying, a predetermined amount of an organic binder such as PVA is added and granulated, formed into a predetermined shape, and degreased in the air, vacuum or nitrogen as required, and then dried. Fire in medium or reducing atmosphere.

At this time, the firing temperature is from 1050 to 1150
By sintering at 10 ° C., particularly 1075 to 1125 ° C. for 1 to 10 hours, the dielectric porcelain of the present invention can be manufactured.

In order to exhibit a core-shell structure, the firing temperature is important. The firing temperature is 1050-1150 ° C
Is desirable. If the temperature is lower than 1050 ° C., sintering does not proceed sufficiently, so that a dense sintered body cannot be obtained. Also,
At a temperature higher than 1150 ° C., BT does not contain Zr, so that Zr easily diffuses into BT, and as a result, BT and B
A TZ solid solution is formed. Firing temperature 1050
By setting the temperature to １1150 ° C., the diffusion of Zr is suppressed, and a core-shell structure of the additive element and BT or BTZ is formed, whereby sintering is promoted and a dense composite structure can be formed.

In the above-described dielectric porcelain, BTZ crystal grains and BT crystal grains have a core-shell structure and an average particle diameter of 0.3 to 1.0 μm. By realizing a coexistence structure of BT crystal particles exhibiting a dielectric constant and excellent temperature characteristics and BTZ crystal particles having a relatively high dielectric constant and excellent DC bias characteristics, it has a high dielectric constant and a flat temperature characteristic. In addition, a dielectric material having excellent DC bias characteristics can be realized.

Further, since the BT crystal particles and BTZ crystal particles have a core-shell structure, the temperature characteristics and the D
C bias characteristics can be improved.

The multilayer electronic component comprising the multilayer ceramic capacitor of the present invention is constituted by alternately laminating the dielectric layers composed of the dielectric ceramic and the internal electrodes composed of the base metal. As the base metal, there are Ni, Cu, and the like, but Ni is preferably used because it is particularly inexpensive.

A method for manufacturing a laminated electronic component according to the present invention will be described. First, a pulling method, a doctor blade method, a reverse roll coater, and a raw material powder obtained by adding a predetermined amount of oxides or carbonates of Mg, Ca, Mn, Y, Er, and Yb to the BT and BTZ powders and mixing them. A dielectric sheet is produced by a well-known forming method such as a gravure coating method, a screen printing method, and a gravure printing method.

The thickness of the dielectric sheet is small,
1 to 10 μm, especially 1 to 5 μm for the reason of large capacity
m is desirable.

Next, a conductive paste containing, for example, Ni is applied to the surface of the dielectric sheet by screen printing.
An internal electrode pattern is formed by coating by a known printing method such as gravure printing or offset printing. The thickness of the internal electrode pattern is desirably 2 μm or less, particularly preferably 1 μm or less, from the viewpoint of miniaturization and high reliability of the capacitor.

Then, a plurality of dielectric sheets to which the conductive paste is applied are laminated and pressed, and the laminated molded body is placed in the atmosphere at 250 to 300 ° C. or in a low oxygen atmosphere having an oxygen partial pressure of 0.1 to 1 Pa in a range of 500 to 800. After degreased at ℃, it is fired in a non-oxidizing atmosphere at 1,050 to 1,150 ° C for 2-3 hours. Further, if desired, the reduced dielectric layer is oxidized by performing reoxidation treatment at 900 to 1100 ° C. for 5 to 15 hours under a low oxygen partial pressure of about 0.1 to 10 ⁻⁴ Pa. This results in a dielectric layer having good insulating properties.

Finally, a Cu paste is applied to each end face of the obtained laminated sintered body and baked, Ni / Sn plating is performed, and external electrodes electrically connected to the internal electrodes are formed to form a laminate. A ceramic capacitor can be manufactured.

In a multilayer electronic component comprising such a multilayer ceramic capacitor, by using a dielectric ceramic having a high dielectric constant and excellent DC bias characteristics, a higher capacity and a smaller size can be further promoted. Also,
By using a dielectric porcelain having a small average particle size, the thickness of the dielectric can be easily reduced, the capacitance can be improved and the size can be reduced, and a base metal such as Ni or Cu can be used as a conductor. By using this, an inexpensive multilayer ceramic capacitor can be obtained.

[0052]

EXAMPLE 1 BaTiO ₃ (average particle size 0.2, 0.4 μm) powder and Ba (Ti _1-x Zr _x ) O produced by a hydrothermal synthesis method
₃ (x is the value shown in Table 1, average particle size 0.2, 0.3, 0.
5 μm) powder, MgCO ₃ , Y ₂ O ₃ , Er ₂ O ₃ , Yb ₂
O ₃ , MnCO ₃ , and CaCO ₃ were added in the amounts shown in Table 1, and a glass filler composed of Si, Li, Ba, and Ca was added in an amount of 1.2% by weight based on the total amount.
The mixture was wet-mixed for 24 hours with a rotary mill using a ZrO ₂ ball of mφ.

After the slurry was discharged and dried, about 2% by weight of an organic binder was added and granulated.
It was formed into a diameter of 16 mm. After the molded body was degreased, it was fired in the air at the temperature shown in Table 1 for 2 hours.

The cross section of the obtained sintered body was observed with a scanning electron microscope (SEM), and the average particle size of the porcelain was determined by an intercept method.

Further, the sample was polished to a thickness of 400 μm, and In—Ga was applied to the upper and lower surfaces of the sample to form electrodes.

The electrical characteristics were measured at -25 using an LCR meter.
AC 1V, measurement frequency 1k in the temperature range of ℃ ~ 85 ℃
The capacitance was measured under the condition of Hz, and the relative permittivity was calculated.
The temperature change rate TCC of the relative dielectric constant is expressed as TCC = ｛ε (T) −
It was determined by the equation of ε (20 ° C.)｝ / ε (20 ° C.). 20
C is the reference temperature.

DC bias dependency of relative permittivity △ ε / ε
Is measured using a polarization-electric field hysteresis characteristic measuring apparatus.
After applying a C offset voltage (800 V) for 30 seconds, a small voltage (100 V) is applied while a DC offset voltage is applied.
Was measured, and the relative permittivity ε (800 V) when a DC bias was applied was calculated from the slope. D
The C bias dependency ／ ε / ε is given by ｛ε (800V) −ε
(0V)｝ / ε (0V). Table 1 shows the results
It was shown to.

[0058]

[Table 1]

From Table 1, it can be seen that the sample N containing no BTZ
o. No. 1 has a large relative dielectric constant of about 3400, but has a large DC bias dependency. On the other hand, in the sample of the present invention in which the coexistence structure of BT and BTZ was realized, the relative dielectric constant was 2000 or more, particularly 2500 or more, the relative dielectric constant change rate was within ± 10%, and the DC bias dependency was −20. Excellent within%.

In the sample of the present invention, when the crystal structure and composition of the particles of the dielectric porcelain were analyzed by a transmission electron microscope, it was found that BT and BTZ crystal particles were present.
In the T and BTZ crystal grains, a difference in composition was confirmed between the central part and the peripheral part. Ba, Ti, and Zr were uniformly present, and Mg and Y, Er, and Yb were detected in the peripheral part. It was not detected at the center, and exhibited a so-called core-shell structure. On the other hand, N
o. 2 and No. In No. 7, BT and BTZ completely dissolved, and the desired structure was not obtained. In addition, no. No good sinterability was obtained for No. 6.

In the case of No. 3 in which the rare earth element is 1.7% by weight or more. 10, No. 14, No. 17, No. In No. 25, the sinterability was poor, and electrical measurements could not be made. Example 2 First, BaTiO ₃ , Ba (Ti
_1-x Zr _x ) A ceramic slurry composed of O ₃ , MgCO ₃ , MnCO ₃ and Y ₂ O ₃ powders, butyral resin, and toluene was prepared, applied by a doctor blade method, and dried at 60 ° C. in a dryer at 60 ° C. After drying for 2 seconds, this was peeled off to form a 9 μm-thick ceramic green sheet, and 10 of these were laminated to form an end face ceramic green sheet layer. Then, these end face ceramic green sheet layers were dried at 90 ° C. for 30 minutes.

The ceramic green sheet layer at the end face was placed on a base plate, pressed with a press machine and glued on the base plate.

On the other hand, the same ceramic slurry as described above was applied on a PET film by a doctor blade method, dried at 60 ° C. for 15 seconds, and a number of 5.5 μm-thick ceramic green sheets were produced.

Next, 5.5% by weight of ethyl cellulose was added to 45% by weight of the total Ni powder having an average particle size of 0.2 μm.
And 55% by weight of a vehicle comprising 94.5% by weight of octyl alcohol were kneaded with three rolls to prepare an internal electrode paste.

Thereafter, the above-mentioned internal electrode paste is printed in an internal electrode pattern on one main surface of the obtained ceramic green sheet using a screen printing apparatus, and has a long side and a short side on the green sheet. A plurality of rectangular internal electrode patterns were formed, dried, and then peeled off.

Thereafter, 300 green sheets on which the internal electrode patterns were formed were laminated on the end face ceramic green sheet layer, and thereafter, the end face ceramic green sheets were laminated, thereby producing a molded body of the capacitor body.

Next, the capacitor body molded body is placed on a mold, and the pressure is gradually increased by a pressing plate of a press machine from the laminating direction, and pressure is applied. The mold was placed and isostatically formed.

Thereafter, the molded body of the capacitor is cut into a predetermined chip shape, and the cut body is formed at 300 ° C. or 0.1 ° C. in the atmosphere.
Heating was performed at 500 ° C. in an oxygen / nitrogen atmosphere of Pa to remove the solder. Further, in an oxygen / nitrogen atmosphere of 10 ^-7 Pa,
Baking at 100 ° C. for 2 hours, and further adding 10 ⁻² Pa of oxygen /
Reoxidation was performed at 1000 ° C. in a nitrogen atmosphere to obtain an electronic component body. After firing, Cu paste was baked at 900 ° C. on the end surface of the electronic component body, and further subjected to Ni / Sn plating to form external terminals connected to internal electrodes.

The thickness of the dielectric layer interposed between the internal electrodes of the multilayer ceramic capacitor thus obtained is 4 μm.
m. The effective number of stacked dielectric layers was 300.

Sample No. 26 and no. 27 shows the measurement results. Note that the DC bias dependency Δε / ε is expressed as Δε (8
V) −ε (0V)｝ / ε (0V), and other characteristics were obtained in the same manner as in Example 1. The results are shown in Table 1. From these results, the relative dielectric constant was 3000 or more, and excellent characteristics were exhibited in both the temperature change rate and the DC bias.

[0071]

According to the dielectric ceramic of the present invention, the relative dielectric constant is 2
000 or more, temperature characteristics of relative permittivity are within ± 10%,
Small and high-capacity monolithic ceramic capacitors having a characteristic that the rate of change of the relative dielectric constant due to application of a DC bias of 2 V / μm is within 20%, whereby the rate of decrease in capacitance is small even when a high voltage is applied. Can be realized.

Claims (4)

[Claims] 1. Ba, Ti, Zr, Mg as metal elements
And perovskite-type BTZ crystal particles containing at least one of Y, Er and Yb, and perovskite-type particles containing Ba, Ti and Mg as metal elements and at least one of Y, Er and Yb Wherein the BTZ crystal particles and the BT crystal particles have a core-shell structure, and have an average particle size of 0.3 to
A dielectric porcelain having a thickness of 1.0 μm. 2. A method according to claim 1, wherein a part of the B site of the BTZ crystal particle is Zr.
The dielectric porcelain according to claim 1, wherein 5 to 30 mol% is substituted. 3. A metal element comprising Ca and / or Mn.
_3. The dielectric ceramic according to claim 1, wherein the content is 0.4% by weight or less in terms of CaCO ₃ and MnCO ₃ . 4. A laminated electronic component in which dielectric layers and internal electrodes made of a base metal are alternately laminated, wherein the dielectric layer is a dielectric material according to claim 1. A laminated electronic component comprising porcelain.