JP5708154B2 - Dielectric porcelain composition and electronic component - Google Patents

Description

  The present invention relates to a dielectric ceramic composition and an electronic component, and more particularly to a dielectric ceramic composition and an electronic component having good life characteristics.

  In recent years, there has been a high demand for downsizing and high performance of electronic components due to higher density of electronic circuits, and for this reason, for example, monolithic ceramic capacitors are becoming smaller and larger capacity, but further improvement of characteristics is required. It has been.

  In response to such a request, for example, in Patent Document 1, the particle size of the dielectric particles included in the dielectric ceramic composition constituting the dielectric layer and the standard deviation of the particle size are set within a predetermined range, thereby stacking layers. Techniques for improving the life characteristics of ceramic capacitors have been studied.

  However, conventionally, the relationship between the half-value width of the particle size distribution of the dielectric particles and the life characteristics has not been studied.

JP 2010-52964 A

  The present invention has been made in view of such a situation, and an object thereof is to provide a dielectric ceramic composition having good life characteristics.

  As a result of intensive studies to achieve the above object, the present inventors have found that the object can be achieved by satisfying a predetermined requirement for the particle size distribution of the dielectric particles contained in the dielectric ceramic composition. The headline and the present invention have been completed.

That is, the dielectric ceramic composition according to the present invention for solving the above problems is
A dielectric ceramic composition comprising dielectric particles,
The dielectric particles are
A main component composed of barium titanate;
A first subcomponent comprising magnesium oxide;
A second subcomponent comprising manganese oxide;
A third subcomponent comprising silicon oxide;
A fourth subcomponent composed of a rare earth element,
The ratio of each subcomponent to 100 moles of the main component is calculated in terms of oxide.
1st subcomponent: 1-3 mol,
Second subcomponent: 0.05 to 1.0 mol,
Third subcomponent: 2 to 12 mol,
4th subcomponent: It is 2-5 mol,
The half-value width of the Gaussian function indicating the particle size distribution of the dielectric particles in the dielectric ceramic composition is W,
When the average particle size of the dielectric particles in the dielectric ceramic composition is R,
W and R satisfy the relational expression of 1.058 ≦ W / R ≦ 1.284 .

  According to the present invention, a dielectric ceramic composition having good life characteristics can be obtained.

  The dielectric ceramic composition preferably has an average particle size R of the dielectric particles of 0.3 μm or less.

The electronic component of the present invention is
An electronic component in which a plurality of internal electrode layers and dielectric layers are alternately laminated,
The dielectric layer is composed of the dielectric ceramic composition.

FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of dielectric particles and grain boundaries constituting a dielectric layer according to an embodiment of the present invention. FIG. 3 is a graph showing a Gaussian function according to an example of the present invention or a comparative example. FIG. 4 is a graph showing the relationship between W / R and accelerated lifetime according to an example or a comparative example of the present invention. FIG. 5 is a graph showing the relationship between W / R and accelerated lifetime according to an example or a comparative example of the present invention. FIG. 6 is a graph showing the relationship between W / R and accelerated lifetime according to an example or a comparative example of the present invention.

  Hereinafter, the present invention will be described based on embodiments shown in the drawings.

<Multilayer ceramic capacitor 1>
As shown in FIG. 1, a multilayer ceramic capacitor 1 according to an embodiment of the present invention includes a capacitor element body 10 having a configuration in which dielectric layers 2 and internal electrode layers 3 are alternately stacked. At both ends of the element body 10, a pair of external electrodes 4 are formed which are electrically connected to the internal electrode layers 3 arranged alternately in the element body 10. Although there is no restriction | limiting in particular in the shape of the element main body 10, Usually, it is set as a rectangular parallelepiped shape. Moreover, there is no restriction | limiting in particular also in the dimension, What is necessary is just to set it as a suitable dimension according to a use.

<Dielectric layer 2>
The dielectric layer 2 is composed of a dielectric ceramic composition according to an embodiment of the present invention. The dielectric ceramic composition includes dielectric particles including a main component made of barium titanate and subcomponents described later.

  The subcomponents are a first subcomponent made of magnesium oxide, a second subcomponent made of manganese oxide, a third subcomponent made of silicon oxide, and a fourth subcomponent made of an oxide of a rare earth element. .

  The ratio of the first subcomponent in the dielectric ceramic composition is 1 to 3 mol in terms of oxide with respect to 100 mol of the main component. By setting the content of the first subcomponent within this range, the life characteristics of the dielectric ceramic composition are improved, and the relative permittivity tends to increase.

  The ratio of the second subcomponent in the dielectric ceramic composition is 0.05 to 1.0 mol in terms of oxide with respect to 100 mol of the main component. By setting the content of the second subcomponent within this range, the life characteristics of the dielectric ceramic composition are improved and the relative dielectric constant tends to increase.

  The ratio of the 3rd subcomponent in a dielectric ceramic composition is 2-12 mol in conversion of an oxide with respect to 100 mol of main components. By setting the ratio of the third subcomponent within this range, the life characteristics of the dielectric ceramic composition are improved, and the relative permittivity tends to increase.

  The ratio of the 4th subcomponent in a dielectric ceramic composition is 2-5 mol in conversion of an oxide with respect to 100 mol of main components. By setting the ratio of the fourth subcomponent within this range, the life characteristics of the dielectric ceramic composition are improved, and the relative permittivity tends to increase.

  Oxides of rare earth elements constituting the fourth subcomponent include Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. There may be mentioned at least one oxide selected.

  Moreover, as a subcomponent which comprises the dielectric particle of this embodiment, it is not limited to the said 1st subcomponent-4th subcomponent, According to a desired characteristic, other than a 1st subcomponent-a 4th subcomponent. Various elements or compounds may be included. In the case of including subcomponents other than the first subcomponent to the fourth subcomponent, the content is particularly limited as long as the ratio of the first subcomponent to the fourth subcomponent is included in each of the above ranges. Not.

  The thickness and the number of laminated layers of the dielectric layer 2 are not particularly limited, and may be determined as appropriate according to desired characteristics and usage.

<Structure of dielectric ceramic composition>
As shown in FIG. 2, the dielectric ceramic composition constituting the dielectric layer 2 includes dielectric particles 20 and grain boundaries 21 formed between a plurality of adjacent dielectric particles 20.

  In the dielectric ceramic composition of the present embodiment, the characteristics of the particle size distribution of the dielectric particles 20 in the dielectric ceramic composition satisfy predetermined requirements.

That is, assuming that the half-value width of the Gaussian function indicating the particle size distribution of the dielectric particles is W and the average particle size of the dielectric particles in the dielectric ceramic composition is R, W and R are 1.00 ≦ W The relational expression /R≦1.30 is satisfied. When W and R satisfy the relational expression of 1.058 ≦ W / R ≦ 1.284 , the life characteristics of the dielectric ceramic composition are improved, and the relative permittivity tends to increase.

  Here, the Gaussian function is a normal distribution function represented by the following formula (1), and the half width of the Gaussian function is represented by the following formula (2).

  In the formulas (1) and (2), R represents the average particle diameter of the dielectric particles in the dielectric ceramic composition, and σ represents the standard deviation of the particle diameter of the dielectric particles in the dielectric ceramic composition.

  The average particle diameter R of the dielectric particles of the present embodiment is preferably 0.3 μm or less. Further, when the average particle diameter R of the dielectric particles is included in the above range, the relative dielectric constant tends to increase by increasing the average particle diameter of the dielectric particles.

  The method for measuring the particle size of the dielectric particles is not particularly limited, and can be measured, for example, by the following method. First, a bright field (BF) image is obtained by photographing a cross section of the dielectric layer 2 using a transmission electron microscope (TEM) or a scanning transmission electron microscope (STEM). In this bright field image, the dielectric particle 20 and a region existing between the dielectric particle 20 and the dielectric particle and having a contrast different from that of the dielectric particle are confirmed as the grain boundary 21. And the average particle area of each dielectric particle in the cross section is measured, and the particle diameter of the dielectric particle can be obtained by calculating the diameter as the equivalent circle diameter.

  Whether or not the contrast is different may be determined visually or may be determined by software or the like that performs image processing.

  Further, the average particle diameter of the dielectric particles may be calculated by an arithmetic average after measuring the particle diameter of 200 or more dielectric particles by the above-described method.

  Further, the fine structure of the dielectric particles 20 of the present embodiment is not particularly limited, and even the dielectric particles as the roasted powder in which the subcomponents are completely dissolved in the main component, May have a structure having a main component phase composed of the main component and a diffusion phase in which the sub component diffuses around the main component phase. The dielectric particles are preferably used as roasted powder.

  The diffusion phase 23 is formed by diffusing at least one subcomponent selected from the first subcomponent to the fourth subcomponent into the main component made of barium titanate. The diffusion phase of the body particles is preferably formed by diffusing at least the fourth subcomponent into the main component composed of barium titanate.

<Internal electrode layer 3>
The conductive material contained in the internal electrode layer 3 is not particularly limited, but Ni or Ni alloy is preferable in the present embodiment. The Ni alloy is preferably an alloy of Ni and one or more elements selected from Mn, Cr, Co and Al, and the Ni content in the alloy is preferably 95% by weight or more. In addition, in Ni or Ni alloy, various trace components, such as P, may be contained about 0.1 wt% or less. What is necessary is just to determine the thickness of the internal electrode layer 3 suitably according to a use etc.

<External electrode 4>
The conductive material contained in the external electrode 4 is not particularly limited, but in the present invention, inexpensive Ni, Cu, and alloys thereof can be used. What is necessary is just to determine the thickness of the external electrode 4 suitably according to a use etc.

<Method for Manufacturing Multilayer Ceramic Capacitor 1>
In the multilayer ceramic capacitor 1 having the dielectric ceramic composition of the present embodiment as a dielectric layer, a green chip is produced by a normal printing method or a sheet method using a paste, like a conventional multilayer ceramic capacitor. After firing, the external electrode is printed or transferred and fired. Hereinafter, although a manufacturing method is demonstrated concretely, the manufacturing method of the multilayer ceramic capacitor of this embodiment is not limited to the following method.

  First, a dielectric material for forming a dielectric layer is prepared, and this is made into a paint to prepare a dielectric layer paste.

  As dielectric materials, first, a raw material of barium titanate, a raw material of magnesium oxide (first subcomponent), a raw material of manganese oxide (second subcomponent), a raw material of silicon oxide (third subcomponent), and a rare earth And an elemental oxide (third subcomponent) raw material. As these raw materials, oxides of the above-described components, mixtures thereof, and composite oxides can be used. In addition, various compounds that become the above-described oxides or composite oxides by firing, such as carbonates and oxalic acid. They can be appropriately selected from salts, nitrates, hydroxides, organometallic compounds, and the like, and can also be used as a mixture.

  In addition to the so-called solid phase method, the raw material of barium titanate can be produced by various methods such as those produced by various liquid phase methods (for example, oxalate method, hydrothermal synthesis method, alkoxide method, sol-gel method, etc.). Can be used.

  Further, when the dielectric layer contains components other than the main component and subcomponents, as described above, oxides of these components, mixtures thereof, and composite oxides are used as the raw materials of the components. Can be used. In addition, various compounds that become oxides or composite oxides by firing can be used.

  What is necessary is just to determine content of each compound in a dielectric raw material so that it may become a composition of the dielectric ceramic composition mentioned above after baking. In the state before forming a paint, the particle size of the dielectric material is usually about 0.1 to 1 μm in average particle size.

  The dielectric layer paste may be an organic paint obtained by kneading a dielectric material and an organic vehicle, or may be a water-based paint.

  An organic vehicle is obtained by dissolving a binder in an organic solvent. A binder is not specifically limited, What is necessary is just to select suitably from normal various binders, such as an ethyl cellulose and polyvinyl butyral. The organic solvent is not particularly limited, and may be appropriately selected from various organic solvents such as terpineol, butyl carbitol, acetone, and toluene depending on the printing method, the sheet method, and the like.

  Further, when the dielectric layer paste is used as a water-based paint, a water-based vehicle in which a water-soluble binder or a dispersant is dissolved in water and a dielectric material may be kneaded. The water-soluble binder is not particularly limited, and for example, polyvinyl alcohol, cellulose, water-soluble acrylic resin, etc. may be used.

  In this embodiment, regardless of whether the dielectric layer paste is an organic paint or a water-based paint, the dielectric material and the organic vehicle, or the dielectric material and the water-based vehicle are wet-ground by a ball mill or a bead mill. The ball diameter or bead diameter used in this case is preferably 0.5 to 1 mm. By setting the ball diameter or bead diameter within this range, the half width W of the Gaussian function indicating the particle size distribution of the dielectric particles can be made relatively large, and as a result, the life characteristics tend to be improved.

  The internal electrode layer paste is obtained by kneading the above-described organic vehicle with the above-described conductive material made of Ni or Ni alloy, or various oxides, organometallic compounds, resinates, etc. that become Ni or Ni alloy after firing. What is necessary is just to prepare. The internal electrode layer paste may contain a common material. The common material is not particularly limited, but preferably has the same composition as the main component.

  The external electrode paste may be prepared in the same manner as the internal electrode layer paste described above.

  There is no restriction | limiting in particular in content of the organic vehicle in each above-mentioned paste, For example, what is necessary is just about 1-5 weight% of binders, for example, about 10-50 weight% of binders. Each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators, and the like as necessary. The total content of these is preferably 10% by weight or less.

  When the printing method is used, the dielectric layer paste and the internal electrode layer paste are printed and laminated on a substrate such as PET, cut into a predetermined shape, and then peeled from the substrate to obtain a green chip.

  In the case of using the sheet method, a green sheet is formed using a dielectric layer paste, and after printing the internal electrode layer paste thereon, these are stacked, cut into a predetermined shape, and formed into a green chip. .

  Before firing, the green chip is subjected to binder removal processing. The binder removal conditions in the present embodiment are not particularly limited, and may be performed under normal binder removal conditions.

  After removing the binder, the green chip is fired. In the firing of the present embodiment, the rate of temperature rise is preferably 100 ° C./hour or less, and more preferably 80 to 60 ° C./hour. By setting the heating rate of the firing within this range, abnormal grain growth of the dielectric particles can be suppressed, and the life characteristics tend to be improved. The holding temperature, holding time, cooling rate, and atmosphere of baking are not particularly limited, and may be performed under normal baking conditions.

  After the firing process, the green chip is annealed. The annealing conditions in this embodiment are not particularly limited, and may be performed under normal annealing conditions.

In the above-described binder removal processing, firing, and annealing, when N ₂ gas, mixed gas, or the like is humidified, for example, a wetter or the like may be used. In this case, the water temperature is preferably about 5 to 75 ° C.

  The binder removal treatment, firing and annealing may be performed continuously or independently.

  The capacitor element body obtained as described above is subjected to end face polishing, for example, by barrel polishing or sand blasting, and an external electrode paste is applied and baked to form the external electrode 4. Then, if necessary, a coating layer is formed on the surface of the external electrode 4 by plating or the like to obtain a multilayer ceramic capacitor. The obtained multilayer ceramic capacitor is mounted on a printed circuit board by soldering or the like and used for various electronic devices.

  The dielectric layer of the multilayer ceramic capacitor of this embodiment manufactured in this way is composed of the dielectric ceramic composition according to this embodiment. Specifically, the characteristics of the particle size distribution of the dielectric particles are predetermined requirements. Meet. Thereby, the lifetime characteristic of a dielectric ceramic composition improves.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the embodiment mentioned above at all, and can be variously modified within the range which does not deviate from the summary of this invention.

  In the embodiment described above, the multilayer ceramic capacitor is exemplified as the electronic component according to the present invention. However, the electronic component according to the present invention is not limited to the multilayer ceramic capacitor, and any electronic component having the above-described configuration may be used.

  Hereinafter, although this invention is demonstrated based on a more detailed Example, this invention is not limited to these Examples.

<Samples 1 to 16>
BaTiO ₃ powder was prepared as a raw material for barium titanate, which is the main component. In addition, as the raw materials for the subcomponents, MgCO ₃ powder, MnO powder, SiO ₂ powder, and Tb ₂ O ₃ powder as Tb oxide raw materials were prepared as Mg oxide raw materials. Note that MgCO ₃ is contained in the dielectric ceramic composition as MgO after firing.

Next, the BaTiO ₃ prepared above and the raw material of the accessory component were wet pulverized with a ball mill for 15 hours and dried to obtain a dielectric raw material. The ball diameter of the ball mill is shown in Table 1 or Table 3.

In addition, the addition amount of each subcomponent is 2.0 mol of MgO and 0.2 mol of MnO in terms of each oxide with respect to 100 mol of barium titanate as the main component in the dielectric ceramic composition after firing. Mol, SiO ₂ was 3.0 mol, and Tb ₂ O ₃ was 3.5 mol.

Next, the obtained dielectric material: 100 parts by weight, polyvinyl butyral resin: 10 parts by weight, dioctyl phthalate (DOP) as a plasticizer: 5 parts by weight, and alcohol: 100 parts by weight as a solvent were mixed by a ball mill. Thus, a dielectric layer paste was obtained. The average particle size of the dielectric material in the paste is shown in Tables 1 and 3.

  In addition to the above, Ni powder: 44.6 parts by weight, terpineol: 52 parts by weight, ethyl cellulose: 3 parts by weight, and benzotriazole: 0.4 parts by weight are kneaded by three rolls to form a slurry. To prepare an internal electrode layer paste.

  And the green sheet of thickness 5 micrometers was formed in PET film using the paste for dielectric material layers produced above. Next, the electrode layer was printed in a predetermined pattern using the internal electrode layer paste thereon, and then the sheet was peeled off from the PET film to produce a green sheet having the electrode layer. Next, a plurality of green sheets having electrode layers were laminated and pressure-bonded to obtain a green laminated body, and the green laminated body was cut into a predetermined size to obtain a green chip.

  Next, the obtained green chip was subjected to binder removal processing, firing step and annealing under the following conditions to obtain an element body as a sintered body.

  The binder removal treatment conditions were temperature rising rate: 25 ° C./hour, holding temperature: 260 ° C., holding time: 8 hours, and atmospheric gas: in air.

The firing conditions are as shown in Tables 1 and 3, with the temperature rising rate as shown in Tables 1 and 3, holding temperature: 1200 to 1300 ° C., holding time: 2 hours, cooling rate: 200 ° C./hour, atmospheric gas: humidified N ₂ and H ₂ mixed gas, oxygen partial pressure: ^10-12 atm.

As for annealing, temperature rising rate: 200 ° C./hour, holding temperature: 1050 ° C., holding time: 2 hours, cooling rate: 200 ° C./hour, atmospheric gas: humidified N ₂ gas, oxygen partial pressure: 10 ⁻⁵ atm did.

  A wetter was used for humidifying the atmospheric gas during firing and annealing.

  Next, after polishing the end face of the obtained element body by sand blasting, an In—Ga alloy was applied as an external electrode to obtain a sample of the multilayer ceramic capacitor shown in FIG.

  About the obtained capacitor | condenser sample, the particle size of the dielectric particle in a dielectric material layer was measured, the average particle size R was calculated | required, the half value width W of the Gaussian function of a particle size distribution was calculated | required, and W / R was calculated. Further, the accelerated life and relative dielectric constant of the obtained capacitor sample were measured by the following methods. The results are shown in Table 2 and Table 4. For sample 1, dielectric loss (tan δ), capacitance-temperature characteristic (TC), and insulation resistance (IR) were also measured.

Dielectric particle size (average particle size and half-value width of particle size distribution)
The capacitor sample was cut perpendicular to the dielectric layer. By performing STEM observation on this cut surface, discriminating between the dielectric particles and grain boundaries, measuring the average area of each dielectric particle for 500 dielectric particles, and calculating the diameter as the equivalent circle diameter The particle size of the dielectric particles was determined.
Next, the average particle diameter by arithmetic mean of the obtained dielectric particles was calculated, the standard deviation was determined, and the half width W was determined by the following equation (2).
For samples 1, 2, 5, and 6, a Gaussian function according to the following equation (1) is shown in FIG.

Accelerated life (MTTF)
The capacitor sample was held at 200 ° C. and 200 V applied, and the time until the resistance (IR) dropped by an order of magnitude was defined as the accelerated life. In this example, it was judged that 5.8 hours or more were good. The relationship between the value of W / R and the accelerated life is shown in FIGS. 4 relates to samples 1 to 8, FIG. 5 relates to samples 9 to 16, and FIG. 6 relates to samples 17 to 37 described later.

Dielectric constant (ε)
The relative dielectric constant was measured with respect to a capacitor sample at a reference temperature of 25 ° C. using a digital LCR meter (4274A manufactured by YHP) under the conditions of a frequency of 1 kHz and an input signal level (measurement voltage) of 0.5 Vrms. Calculated from capacity (no unit). A higher dielectric constant is preferable.

Dielectric loss (tan δ)
Dielectric loss tan δ was measured for a capacitor sample under the conditions of a frequency of 1 kHz and an input signal level (measurement voltage) of 1 Vrms with a digital LCR meter (YHP 4274A) at a reference temperature of 25 ° C.

Capacity temperature characteristics (TC)
Capacitor sample was measured with a digital LCR meter (4274A manufactured by YHP) under the conditions of frequency 1 kHz and input signal level (measurement voltage) 1 Vrms. The capacitance-temperature characteristic TC was evaluated by measuring the capacitance change rate (ΔC / C) with respect to the temperature within a temperature range of 55 to 85 ° C. In this example, a material satisfying ± 15% or less (X5R characteristic of EIA standard) within a temperature range of −55 to 85 ° C. was considered good.

Insulation resistance (IR)
With respect to the capacitor sample, the insulation resistance (IR) at 25 ° C. was measured. The voltage at the time of measuring the insulation resistance (IR) was DC 100 V, and the value was 60 seconds after the start of application (unit: “Ω”).

<Samples 17 to 37>
In Samples 17 to 37, MgO, MnO, SiO ₂ and rare earths were added in terms of oxides with respect to 100 mol of barium titanate, which is the main component in the fired dielectric ceramic composition. Capacitor samples were prepared in the same manner as Samples 1 to 16, except that the oxides of the elements were changed as shown in Table 5 and the types of rare earth elements were changed as shown in Table 5. . For the obtained capacitor sample, the particle size of the dielectric particles in the dielectric layer is measured in the same manner as in Samples 1 to 16, the average particle size R is obtained, and the half width W of the Gaussian function of the particle size distribution is obtained. The W / R was calculated, and the accelerated lifetime and relative dielectric constant were measured. The results are shown in Table 6.

From Table 1 to Table 4, when the value of W / R is included in the range of 1.058 ≦ W / R ≦ 1.284 (samples 1-2 , 9-10 , 12 ), It was confirmed that the accelerated lifetime was higher than when the value was not included in the range of 1.058 ≦ W / R ≦ 1.284 (samples 3 to 8, 11, 13 to 16).

From Tables 1 to 4, when the ball diameter of the ball mill is less than 2.0 mm and the rate of temperature increase during firing is less than 200 ° C./hour (samples 1 to 2 , 9 to 10 , 12 ) It was confirmed that the value of W / R was included in the range of 1.058 ≦ W / R ≦ 1.284 .

  This is because by reducing the ball diameter of the ball mill, the particle size of the dielectric material contained in the dielectric layer paste can be made smaller. As a result, the solid solution of each subcomponent in the barium titanate is reduced. It is considered that the full width at half maximum W of the particle size distribution is increased and W / R is increased due to the increase in the number of dielectric particles in which the subcomponent is completely dissolved.

  Moreover, since the abnormal grain growth could be suppressed by lowering the heating rate at the time of firing, the average particle diameter could be reduced, and as a result, W / R is considered to be reduced. And since such a capacitor | condenser sample has suppressed abnormal grain growth, it is thought that the accelerated lifetime improved.

  Moreover, it has confirmed that the one where the average particle diameter of a dielectric material particle was larger (samples 9-12) became high.

Furthermore, the dielectric loss (tan δ) of Sample 1 is 1.2%, and the capacity-temperature characteristic (TC) is −3.4% at −55 ° C. and −7.8% at 85 ° C., which satisfies X5R. The insulation resistance (IR) was 2.0 × 10 ¹¹ Ω, and it was confirmed that all showed good values.

From Tables 5 and 6, the ratio of each subcomponent to 100 mol of the main component of the dielectric particles constituting the dielectric ceramic composition is MgO: 1 to 3 mol, MnO: 0.05 to 1 mol in terms of oxide. , SiO2: 2 to 12 mol, rare earth oxide: 2 to 5 mol (samples 17 to 18, 20 to 21), the range of W / R is 1.058 ≦ W / R ≦ 1.284 It was confirmed that the accelerated lifetime was higher than that in the case where the ratio was included in the range and the ratio of the subcomponent was out of the range (Samples 22 to 37).

DESCRIPTION OF SYMBOLS 1 ... Multilayer ceramic capacitor 10 ... Element main body 2 ... Dielectric layer 20 ... Dielectric particle 21 ... Grain boundary 3 ... Internal electrode layer 4 ... External electrode

Claims (3)

A dielectric ceramic composition comprising dielectric particles,
The dielectric particles are
A main component composed of barium titanate;
A first subcomponent comprising magnesium oxide;
A second subcomponent comprising manganese oxide;
A third subcomponent comprising silicon oxide;
A fourth subcomponent composed of a rare earth element,
The ratio of each subcomponent to 100 moles of the main component is calculated in terms of oxide.
1st subcomponent: 1-3 mol,
Second subcomponent: 0.05 to 1.0 mol,
Third subcomponent: 2 to 12 mol,
4th subcomponent: It is 2-5 mol,
The half-value width of the Gaussian function indicating the particle size distribution of the dielectric particles in the dielectric ceramic composition is W,
When the average particle size of the dielectric particles in the dielectric ceramic composition is R,
A dielectric ceramic composition characterized in that W and R satisfy a relational expression of 1.058 ≦ W / R ≦ 1.284 . The dielectric ceramic composition according to claim 1, wherein an average particle diameter R of the dielectric particles is 0.3 μm or less. An electronic component in which a plurality of internal electrode layers and dielectric layers are alternately laminated,
An electronic component in which the dielectric layer is composed of the dielectric ceramic composition according to claim 1.

Images