Dielectric ceramic composition

Abstract

The present invention provides a dielectric ceramic composition that can obtain orientation characteristics for a predetermined surface. [Solution] The invention comprises a plurality of nanoparticles that form a film by being arranged in a two-dimensional direction via grain boundaries, with the (100) plane of the plurality of nanoparticles being oriented on the first main surface of the film.

Description

[Technical Field]

[0001] This invention relates to dielectric ceramic compositions. [Background technology]

[0002] A configuration is needed in which a predetermined surface is oriented for fine particles of a ceramic material having a perovskite structure (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2019 / 05474 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, the structure of Patent Document 1 is a laminate formed by stacking powdered fine particles. In such a laminate, it is difficult to orient the fine particles to a predetermined surface, making it difficult to obtain the desired orientation characteristics.

[0005] This invention has been made in view of the above problems, and aims to provide a dielectric ceramic composition that can obtain orientation characteristics of a predetermined surface. [Means for solving the problem]

[0006] The dielectric ceramic composition according to the present invention mainly comprises a ceramic having a perovskite structure and includes a plurality of nanoparticles that form a film by being aligned in a two-dimensional direction via grain boundaries, wherein the plurality of nanoparticles have their (100) planes oriented on the first main surface of the film.

[0007] In the dielectric ceramic composition described above, the plurality of nanoparticles may be oriented such that, when XRD measurements are performed with the direction perpendicular to the first main surface set as the surface normal direction, the peak intensities of the (100) plane and the (200) plane are higher than the peak intensities of the other planes.

[0008] In the XRD measurement of the dielectric ceramic composition described above, if the peak intensity of the (100) plane is defined as the first peak intensity S1, and the highest peak intensity other than the (100) plane and the (200) plane is defined as the second peak intensity S2, then S1 / S2 may be 1 or more.

[0009] In the dielectric ceramic composition described above, the average diameter of the plurality of nanoparticles may be 5 nm or more and 1000 nm or less.

[0010] In the dielectric ceramic composition described above, the thickness of the film may be 5 nm or more and 1000 nm or less.

[0011] In the dielectric ceramic composition described above, the main component of the plurality of nanoparticles may be barium titanate.

[0012] In the dielectric ceramic composition described above, a titanium oxide film may be provided on the second main surface of the film. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a dielectric ceramic composition that can obtain orientation characteristics of a predetermined surface. [Brief explanation of the drawing]

[0014] [Figure 1] This is a perspective view of a dielectric ceramic composition according to the first embodiment. [Figure 2] This figure illustrates the XRD measurement results for a film of a dielectric ceramic composition when nanoparticles that are not oriented in a predetermined direction are arranged in a two-dimensional direction. [Figure 3] This figure illustrates the XRD measurement results of a dielectric ceramic composition according to the first embodiment. [Figure 4] (a) and (b) are XZ cross-sections of the dielectric ceramic composition. [Figure 5] It is a flowchart for explaining a method of manufacturing a dielectric ceramic composition. [Figure 6] (a) to (c) are cross-sectional views corresponding to the flowchart of FIG. 5. [Figure 7] It is a partial cross-sectional perspective view of the multilayer ceramic capacitor according to the second embodiment. [Figure 8] It is a cross-sectional view taken along line A-A of FIG. 7. [Figure 9] It is a cross-sectional view taken along line B-B of FIG. 7. [Figure 10] It is a cross-sectional view illustrating a dielectric ceramic composition. [Figure 11] It is a cross-sectional view illustrating a dielectric ceramic composition. [Figure 12] It is a diagram showing the results of surface SEM observation of Examples 1 to 3. [Figure 13] It is a diagram showing the results of cross-sectional SEM observation of Examples 1 to 3. [Figure 14] It is a diagram showing the results of X-ray diffraction measurement of Examples 1 to 3.

Mode for Carrying Out the Invention

[0015] Hereinafter, embodiments will be described with reference to the drawings.

[0016] (First Embodiment) FIG. 1 is a perspective view of a dielectric ceramic composition 200 according to the first embodiment. In FIG. 1, the X-axis direction, the Y-axis direction, and the Z-axis direction are axial directions orthogonal to each other. As illustrated in FIG. 1, the dielectric ceramic composition 200 has a configuration in which a plurality of nanoparticles 210 are connected to each other via grain boundaries 220 and arranged in a two-dimensional direction (XY plane). Thereby, the dielectric ceramic composition 200 constitutes a film having a thickness in the Z-axis direction. The (100) plane of the crystal lattice is oriented in the first main surface (the upper surface in FIG. 1) among the two main surfaces of the nanoparticles 210.

[0017] The nanoparticles 210 have a nano-order size. In the present embodiment, the average diameter of the nanoparticles 210 is 5 nm or more and 1000 nm or less, 5 nm or more and 500 nm or less, or 5 nm or more and 200 nm or less. The average diameter of the nanoparticles 210 means the value obtained by measuring and averaging the sizes of 10 or more nanoparticles 210. Here, the size of the nanoparticles 210 means the distance (length) between two separated points on the outer periphery of the electron microscope image (such as SEM image or TEM image) of the nanoparticles 210, which is the largest distance. In other words, it means the longest length in the electron microscope image (such as SEM image or TEM image) of the nanoparticles.

[0018] The nanoparticles 210 mainly contain a ceramic material having a perovskite structure represented by the general formula ABO3. The perovskite structure contains ABO deviating from the stoichiometric composition. 3-α For example, as the ceramic material, at least one of barium titanate (BaTiO3), calcium zirconate (CaZrO3), calcium titanate (CaTiO3), strontium titanate (SrTiO3), magnesium titanate (MgTiO3), Ba forming a perovskite structure 1-x-y Ca x Sr y Ti 1-z Zr z O3 (0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 1) etc. can be selected and used. Ba 1-x-y Ca x Sr y Ti 1-z Zr z O3 are barium strontium titanate, barium calcium titanate, barium zirconate, barium zirconium titanate, calcium zirconium titanate, and barium calcium zirconium titanate, etc. For example, in the nanoparticles 210, the main component ceramic is contained at 90 at% or more.

[0019] In the dielectric ceramic composition 200 according to this embodiment, the nanoparticles 210 are not arranged irregularly, but rather the (100) plane of the nanoparticles 210 is oriented on the first main surface, thus providing orientation characteristics. Furthermore, since the nanoparticles 210 are connected to each other via grain boundaries 220 and arranged in a two-dimensional direction (XY plane), there is no need to arrange each nanoparticle to be oriented in a predetermined direction, as is the case with powder materials, thus easily providing orientation characteristics.

[0020] For example, since each nanoparticle 210 is connected via the grain boundary 220 with its (100) plane oriented on the first principal surface, lattice strain occurs in each nanoparticle. Therefore, lattice strain occurs with the crystal lattice directions aligned. As a result, the relative permittivity of the dielectric ceramic composition 200 is improved. For example, the dielectric ceramic composition 200 has a relative permittivity of 100 to 10000 and a relative permittivity of 1000 to 5000.

[0021] Generally, the smaller the crystal grain size, the lower the relative permittivity. However, in this embodiment, a high relative permittivity can be achieved even with fine particles such as nanoparticles. For example, a higher relative permittivity can be achieved than when a film of the same thickness is formed by sputtering using the same material as the nanoparticles 210. Therefore, the dielectric ceramic composition 200 is particularly suitable for applications where fine particles are desired as crystal grains and a high relative permittivity is required.

[0022] Figure 2 illustrates the results of XRD measurements on a dielectric ceramic composition film when nanoparticles that are not oriented in a predetermined direction are arranged in a two-dimensional direction (XY plane). In the XRD measurement, the plane normal direction of the film being measured is set to the Z-axis direction. In the following XRD measurements as well, the plane normal direction is set to the Z-axis direction. As illustrated in Figure 2, when nanoparticles are not oriented in a predetermined direction, peaks appear on multiple planes. In the example in Figure 2, the peak intensity is highest on the (110) plane.

[0023] In contrast, Figure 3 illustrates the XRD measurement results of the dielectric ceramic composition 200 according to this embodiment. As illustrated in Figure 3, in this embodiment, the peak intensity of the (100) plane is high. Furthermore, since the nanoparticles 210 are mainly composed of ceramics having a perovskite structure, the peak intensity of the (200) plane is also high. Thus, in this embodiment, the orientation of the (100) plane on the first main plane of the nanoparticles 210 means that when XRD measurements are performed with the Z-axis direction as the plane normal direction, the peak intensities of the (100) plane and the (200) plane are higher than the peak intensities of the other planes.

[0024] When the (100) plane of the nanoparticles 210 is oriented on the first main surface of the dielectric ceramic composition 200, in XRD measurements, the peak intensity of the (100) plane is relatively higher than the peak intensities of the other planes, compared to the peak intensities of the (100) plane and the (200) plane. When the peak intensity of the (100) plane is defined as the first peak intensity S1, and the highest peak intensity of the planes other than the (100) plane and the (200) plane is defined as the second peak intensity S2, the ratio S1 / S2 is preferably 1 or more, more preferably 5 or more, and even more preferably 10 or more.

[0025] Figures 4(a) and 4(b) show the XZ cross-section (or YZ cross-section) of the dielectric ceramic composition 200. As illustrated in Figure 4(a), one nanoparticle 210 may be arranged in the thickness direction, with each nanoparticle 210 aligned in a two-dimensional direction (XY plane). Alternatively, as illustrated in Figure 4(b), multiple nanoparticles 210 may be arranged in the thickness direction, with each nanoparticle 210 aligned in a two-dimensional direction (XY plane).

[0026] The thickness of the dielectric ceramic composition 200 is, for example, 5 nm to 1000 nm, 5 nm to 500 nm, or 5 nm to 200 nm.

[0027] Figure 5 is a flowchart illustrating the manufacturing method of the dielectric ceramic composition 200. Figures 6(a) to 6(c) are cross-sectional views corresponding to the flowchart in Figure 5.

[0028] (Substrate preparation process) First, prepare a substrate 230 as illustrated in Figure 6(a). The substrate 230 should preferably be a crystalline substrate with a lattice constant close to that of the TiO2 film (titanium oxide film) oriented on the (001) plane to be deposited. Typical examples include LaAlO3, SrTiO3, Nb-doped SrTiO3, Pt, and SrRuO3. The plane normal direction of the substrate 230 is defined as the Z-axis direction.

[0029] (Epitaxial growth process) Next, as illustrated in Figure 6(b), a TiO2 film 240 is deposited on the (001) plane of the substrate 230 by epitaxial growth. For example, the TiO2 film 240 can be grown epitaxially using a method such as PLD (Pulsed Laser Deposition). By growing the TiO2 film 240 epitaxially, the (001) plane of the TiO2 film 240 becomes oriented in the Z-axis direction. The TiO2 film 240 may be polycrystalline or single-crystal.

[0030] As the thickness of the TiO2 film 240 increases, the orientation of the (001) plane of the TiO2 film 240 tends to decrease; therefore, a thinner TiO2 film 240 is preferable. In this embodiment, the thickness of the TiO2 film 240 is preferably 1000 nm or less, more preferably 500 nm or less, and even more preferably 200 nm or less.

[0031] (Hydrothermal synthesis process) Next, as illustrated in Figure 6(c), multiple nanoparticles 210 are synthesized from the TiO2 film 240 using a hydrothermal synthesis method. By using the hydrothermal synthesis method, the perovskite particles synthesized from the TiO2 film 240 can be made into microparticles. As a result, multiple nanoparticles 210 can be synthesized from the TiO2 film 240.

[0032] In particular, because the (001) plane of the TiO2 film 240 is oriented in the Z-axis direction, the A-site elements constituting the perovskite can easily penetrate the TiO2 film 240. For example, if the nanoparticles 210 are barium titanate, the barium can easily penetrate the TiO2 film 240, and fine particles can be obtained.

[0033] By following the above steps, a dielectric ceramic composition 200 can be manufactured.

[0034] (Second Embodiment) Figure 7 is a partial cross-sectional perspective view of a multilayer ceramic capacitor 100 according to the second embodiment. Figure 8 is a cross-sectional view taken along line AA in Figure 7. Figure 9 is a cross-sectional view taken along line BB in Figure 7. As illustrated in Figures 7 to 9, the multilayer ceramic capacitor 100 comprises a base body 10 having a substantially rectangular parallelepiped shape and external electrodes 20a and 20b provided on two opposing end faces of either of the base body 10. Of the four faces of the base body 10 other than the two end faces, the two faces other than the top and bottom faces in the stacking direction are referred to as side faces. The external electrodes 20a and 20b extend to the top face, bottom face and two side faces of the base body 10 in the stacking direction. However, the external electrodes 20a and 20b are spaced apart from each other.

[0035] In Figures 7 to 9, the Z-axis direction (first direction) is the stacking direction, and is the direction in which each internal electrode layer faces another. The X-axis direction (second direction) is the length direction of the base body 10, and is the direction in which the two end faces of the base body 10 face each other, and is the direction in which the external electrode 20a and external electrode 20b face each other. The Y-axis direction (third direction) is the width direction of the internal electrode layer, and is the direction in which the two sides of the base body 10 (excluding the two end faces) face each other. The X-axis direction, the Y-axis direction, and the Z-axis direction are mutually orthogonal.

[0036] The base body 10 has a structure in which dielectric layers 11 containing a ceramic material that functions as a dielectric and internal electrode layers 12 are alternately stacked. The edges of each internal electrode layer 12 are alternately exposed to the end face of the base body 10 where the external electrode 20a is provided and the end face where the external electrode 20b is provided. As a result, each internal electrode layer 12 is alternately electrically connected to the external electrode 20a and the external electrode 20b. Consequently, the multilayer ceramic capacitor 100 has a structure in which multiple dielectric layers 11 are stacked via internal electrode layers 12. Furthermore, in the laminate of dielectric layers 11 and internal electrode layers 12, the outermost layer in the stacking direction is the internal electrode layer 12, and the top and bottom surfaces of the laminate are covered by a cover layer 13. The cover layer 13 mainly consists of a ceramic material. For example, the cover layer 13 may have the same composition as the dielectric layer 11 or a different composition. Furthermore, the configuration is not limited to that shown in Figures 7 to 9, as long as the internal electrode layer 12 is exposed on two different surfaces and is electrically connected to different external electrodes.

[0037] The dimensions of the multilayer ceramic capacitor 100 are, for example, 0.25 mm in length, 0.125 mm in width, and 0.125 mm in height, or 0.4 mm in length, 0.2 mm in width, and 0.2 mm in height, or 0.6 mm in length, 0.3 mm in width, and 0.3 mm in height, or 1.0 mm in length, 0.5 mm in width, and 0.5 mm in height, or 3.2 mm in length, 1.6 mm in width, and 1.6 mm in height, or 4.5 mm in length, 3.2 mm in width, and 2.5 mm in height, but are not limited to these dimensions.

[0038] The internal electrode layer 12 is mainly composed of base metals such as nickel (Ni), copper (Cu), tin (Sn), or alloys containing these. Precious metals such as platinum (Pt), palladium (Pd), silver (Ag), and gold (Au), or alloys containing these, may also be used as the internal electrode layer 12. The average thickness of each internal electrode layer 12 in the Z-axis direction is, for example, 50 nm to 10 μm, 100 nm to 5 μm, or 200 nm to 3 μm. The thickness of the internal electrode layer 12 can be measured by observing the cross-section of the multilayer ceramic capacitor 100 with an SEM (scanning electron microscope), measuring the thickness at 10 points for each of 10 different internal electrode layers 12, and deriving the average value of all measurement points.

[0039] The dielectric layer 11 is the dielectric ceramic composition 200 described in the first embodiment. The thickness of the dielectric layer 11 is, for example, 5 nm to 1000 nm, 5 nm to 500 nm, 5 nm to 300 nm, 5 nm to 200 nm, or 5 nm to 100 nm. The thickness of the dielectric layer 11 can be measured by observing the cross-section of the multilayer ceramic capacitor 100 with an SEM (scanning electron microscope), measuring the thickness at 10 points for each of the 10 different dielectric layers 11, and deriving the average value of all measurement points.

[0040] As illustrated in Figure 8, the region where the internal electrode layer 12 connected to the external electrode 20a and the internal electrode layer 12 connected to the external electrode 20b face each other is a region in the multilayer ceramic capacitor 100 where capacitance is generated. Therefore, this region where capacitance is generated is referred to as the capacitance section 14. In other words, the capacitance section 14 is a region where adjacent internal electrode layers 12 connected to different external electrodes face each other.

[0041] The region where internal electrode layers 12 connected to external electrode 20a face each other without being connected to an internal electrode layer 12 connected to external electrode 20b is called the end margin 15. Similarly, the region where internal electrode layers 12 connected to external electrode 20b face each other without being connected to an internal electrode layer 12 connected to external electrode 20a is also called the end margin 15. In other words, the end margin 15 is the region where internal electrode layers 12 connected to the same external electrode face each other without being connected to an internal electrode layer 12 connected to a different external electrode. The end margin 15 is a region where no capacitance is generated.

[0042] As illustrated in Figure 9, in the element 10, the side margin 16 is a region provided to cover the two side edges (the edges in the Y-axis direction) of the dielectric layer 11 and the internal electrode layer 12. In other words, the side margin 16 is a region provided outside the capacitance portion 14 in the Y-axis direction. The side margin 16 is also a region that does not generate capacitance.

[0043] In the multilayer ceramic capacitor 100 according to this embodiment, the dielectric ceramic composition 200 according to the first embodiment is used as the dielectric layer 11. Although the dielectric ceramic composition 200 is a thin film, it has a high relative permittivity, so increasing the number of layers improves the capacitance of the multilayer ceramic capacitor 100. When the dielectric ceramic composition 200 is fabricated on the substrate 230 as explained in Figure 6(c), the dielectric ceramic composition 200 can be peeled off the substrate 230 and used as the dielectric layer 11. Alternatively, the TiO2 film 240 can be peeled off the substrate 230, and the dielectric ceramic composition 200 can be provided on the TiO2 film 240 as illustrated in Figure 10, and used as the dielectric layer 11. In this case, since the TiO2 film 240 is denser than the dielectric ceramic composition 200, short circuits can be suppressed.

[0044] In this embodiment, a multilayer ceramic capacitor was described as an example of a multilayer ceramic electronic component, but it is not limited to that. For example, the dielectric ceramic composition 200 according to the first embodiment may be applied to the dielectric layer of other multilayer ceramic electronic components such as varistors and thermistors.

[0045] (Other uses) Barium titanate (BaTiO3) and strontium titanate (SrTiO3), which are perovskite-type oxides, are attracting attention as photocatalysts. These materials are particularly likely to be used for hydrogen production through the photodecomposition of water. For example, by regularly arranging strontium titanate nanoparticles and promoting the interparticle movement of generated electrons and holes, highly efficient hydrogen production can be achieved. Therefore, by using dielectric ceramic composition 200 as a photocatalyst, highly efficient charge transfer and photocatalytic reactions can be realized.

[0046] For example, by combining barium titanate and titanium oxide (TiO2), which have different band structures, electrons and holes generated by photoexcitation are efficiently separated between these materials, and recombination is suppressed. This effect is thought to improve the efficiency of the photocatalytic reaction. In the structure illustrated in Figure 10, since nanoparticles 210 are epitaxially formed on the TiO2 film 240, efficient charge transfer occurs at a highly compatible interface, promoting the photocatalytic reaction.

[0047] Furthermore, the internal electric field generated by the ferroelectricity of barium titanate is thought to improve photocatalytic activity by helping to separate electrons and holes generated by photoexcitation and suppressing recombination. Therefore, by using the structure exemplified in Figure 10 as a photocatalyst, photocatalytic activity can be improved.

[0048] Pure strontium titanate and pure barium titanate respond only to ultraviolet light, but by doping them with dissimilar metals or combining them with other semiconductor materials, their visible light response can be enhanced, allowing for effective utilization of sunlight. Therefore, visible light responsiveness can be imparted to each nanoparticle 210 of the dielectric ceramic composition 200 by doping them with a dissimilar metal or by coating them with a semiconductor material having an appropriate band structure.

[0049] Furthermore, if the substrate 230 on which the structure illustrated in Figure 10 is formed is conductive, materials such as Nb-doped SrTiO3, Pt, and SrRuO3 can also be used as photoelectrodes. For example, water splitting reactions using photoelectrodes are superior to powder photocatalyst systems in that the generated oxygen and hydrogen can be easily separated and recovered. In addition, by combining them with organic-inorganic perovskites and photosensitizers, which are attracting attention as next-generation solar cells, they can be used in solar cells and photodetectors.

[0050] Alternatively, as illustrated in Figure 11, one or more nanoparticles 210 may be arranged on a film formed by arranging multiple nanoparticles 210 in a two-dimensional direction (XY plane), with each nanoparticle 210 spaced apart in the XY direction. This configuration provides the effect of collecting photogenerated charges and promoting the adsorption of reactants. Furthermore, if the configuration in Figure 11 is applied to the dielectric layer 11 of a multilayer ceramic capacitor 100, the nanoparticles 210 will exert an anchoring effect, improving adhesion with the internal electrode layer 12 and suppressing delamination. [Examples]

[0051] (Example 1) Barium hydroxide octahydrate (Ba(OH)2·8H2O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 0.25 mmol) with polyethylene glycol 400 (H(OCH2CH2) n OH (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 2 mL), ethanol (CH3CH2OH, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 0.75 mL), and distilled water (H2O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 2.25 mL) were added, and the mixture was sonicated until dissolved. Next, this mixture and a TiO2 / Nb-doped SrTiO3 substrate with the (100) plane oriented in the direction of the plane normal were sealed in a stainless steel reaction vessel (manufactured by San-ai Kagaku Co., Ltd.) equipped with a 25 mL polytetrafluoroethylene (PTFE) inner cylinder, and heated at 150°C for 24 hours. After that, it was cooled to room temperature to obtain a laminated film of barium titanate nanoparticles.

[0052] (Example 2) A laminated film of barium titanate nanoparticles was obtained in the same manner as in Example 1, except that distilled water was replaced with a 1 mol / L sodium hydroxide aqueous solution (NaOH, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and the heating time was changed from 24 hours to 5 hours.

[0053] (Example 3) A laminated film of barium titanate nanoparticles was obtained in the same manner as in Example 2, except that the 1 mol / L sodium hydroxide aqueous solution was changed to a 5 mol / L sodium hydroxide aqueous solution.

[0054] (Surface SEM observation) The surface of the barium titanate nanoparticle stacked films of Examples 1-3 was observed under magnification using a Schottky field emission scanning electron microscope ("JSM-IT800HL," manufactured by JEOL Ltd.). The results are shown in Figure 12. In addition, the obtained electron microscope images were analyzed using image processing software ("ImageJ," National Institutes of Health, USA) to determine the lengths of 50 secondary particles contained in the magnified images of the barium titanate nanoparticle stacked films, and their average values ​​were calculated. The results are shown in Table 1. [Table 1]

[0055] As shown in Figure 12 and Table 1, it was revealed that the size of the secondary particles formed from the resulting barium titanate nanoparticles increases as the concentration of hydroxide ions in the solution subjected to the hydrothermal reaction increases.

[0056] (Cross-sectional SEM observation) Cross-sections of the barium titanate nanoparticle stacked films from Examples 1-3 were observed under magnification using a Schottky field emission scanning electron microscope ("JSM-IT800SHL," manufactured by JEOL Ltd.). The results are shown in Figure 13. As shown in Figure 13 and Table 2, it became clear that the thickness of the resulting barium titanate nanoparticle stacked film increased as the concentration of hydroxide ions in the solution subjected to the hydrothermal reaction increased. [Table 2]

[0057] (X-ray diffraction measurement) The multilayer films of barium titanate nanoparticles from Examples 1-3 were analyzed using an X-ray diffractometer ("MiniFlex600-C," Rigaku Corporation). The results are shown in Figure 14. As shown in Figure 14, only the (100) and (200) plane peaks of barium titanate were observed, indicating that barium titanate grew on titanium oxide with a uniform crystal orientation. Furthermore, the peak intensity of barium titanate increased as the concentration of hydroxide ions in the solution subjected to the hydrothermal reaction increased.

[0058] Although embodiments of the present invention have been described in detail above, the present invention is not limited to these specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims. [Explanation of Symbols]

[0059] 10 Base Body 11 Dielectric layer 12 Internal electrode layer 13. Cover layer 14 Capacity part 15 End margin 16 Side margins 20a,20b external electrode 100 Multilayer Ceramic Capacitors 200 Dielectric ceramic composition 210 nanoparticles 220 grain boundaries 230 circuit boards 240 TiO2 film

Claims

1. It comprises a ceramic with a perovskite structure as its main component, and includes multiple nanoparticles that form a film by aligning in a two-dimensional direction via grain boundaries. The plurality of nanoparticles are oriented with (100) planes on the first main surface of the film in a dielectric ceramic composition.

2. The dielectric ceramic composition according to claim 1, wherein the plurality of nanoparticles are oriented such that when XRD measurements are performed with the direction perpendicular to the first main surface set as the surface normal direction, the peak intensities of the (100) plane and the (200) plane are higher than the peak intensities of the other planes.

3. The dielectric ceramic composition according to claim 2, wherein, in the XRD measurement, the peak intensity of the (100) plane is defined as the first peak intensity S1, and the highest peak intensity other than the (100) plane and the (200) plane is defined as the second peak intensity S2, and S1 / S2 is 1 or more.

4. The dielectric ceramic composition according to claim 1, wherein the average diameter of the plurality of nanoparticles is 5 nm or more and 1000 nm or less.

5. The dielectric ceramic composition according to claim 1, wherein the thickness of the film is 5 nm or more and 1000 nm or less.

6. The dielectric ceramic composition according to claim 1, wherein the main component of the plurality of nanoparticles is barium titanate.

7. The dielectric ceramic composition according to claim 1, further comprising a titanium oxide film on the second main surface of the aforementioned film.

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