Dielectric composition and electronic component

Abstract

The present invention is a dielectric composition comprising a main component represented by (Ba x Sr (1‑x) ) m Ta4O 12 and a first sub-component, m is 1.95≤m≤2.40, the first sub-component is silicon and manganese, the content of silicon in the dielectric composition is 5.0-20.0 mol parts in terms of SiO2 when the content of the main component in the dielectric composition is 100 mol parts, and the content of manganese in the dielectric composition is 1.0-4.5 mol parts in terms of MnO.

Description

TECHNICAL FIELD

[0001] The present application relates to a dielectric composition and an electronic component. BACKGROUND

[0002] For example, as shown in Patent Document 1, a dielectric composition which does not contain lead or alkali metal and has a high relative dielectric constant has been developed.

[0003] However, the newly developed new dielectric composition has a problem that a high density of the dielectric cannot be obtained if firing is not performed at a high temperature.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2000-103671 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] The present application has been achieved in view of such circumstances, and has an object to provide a new dielectric composition which has a high sintering density even if firing is performed at a relatively low temperature, and which has a high relative dielectric constant.

[0009] MEANS OF SOLVING THE PROBLEMS

[0010] The dielectric composition of the first aspect of the present application contains a main component represented by (Ba x Sr (1-x) ) m Ta4O 12 and a first subcomponent,

[0011] The above m is 1.95 ≤ m ≤ 2.40,

[0012] The above first subcomponent is silicon and manganese,

[0013] When the content of the above main component in the above dielectric composition is set to 100 mol parts,

[0014] The content of silicon in the above dielectric composition is 5.0 to 20.0 mol parts in terms of SiO2,

[0015] The content of manganese in the above dielectric composition is 1.0 to 4.5 mol parts in terms of MnO.

[0016] The dielectric composition of the first aspect of the present application has a high sintering density even when sintered at a low temperature (e.g., 1200 to 1355°C), and has a high relative dielectric constant. Although the reason is not clear, it is considered to be the following reason. It is considered that, when m is within the above range, the dielectric composition contains a prescribed amount of silicon and manganese, and thus a low sintering start temperature is obtained. Thus, even when sintered at a low temperature, a high sintering density is easily obtained, and the relative dielectric constant is also improved.

[0017] Preferably, the above m is 2.10 ≤ m ≤ 2.40. It is considered that, thereby, the wettability of the main component and the first subcomponent is improved, and a low sintering start temperature is obtained. Thus, a high sintering density is obtained even at a low temperature, and the relative dielectric constant is further improved.

[0018] Preferably, the above dielectric composition contains at least one selected from vanadium, magnesium, zirconium, and tungsten as a second subcomponent,

[0019] When the content of the above main component in the above dielectric composition is set to 100 mol parts,

[0020] In the above dielectric composition, 0.25 to 1.0 mol parts of at least one selected from vanadium, magnesium, zirconium, and tungsten are contained in a prescribed oxide conversion amount, wherein,

[0021] The content of vanadium is converted to V2O5,

[0022] The content of magnesium is converted to MgO,

[0023] The content of zirconium is converted to ZrO2,

[0024] The content of tungsten is converted to WO3.

[0025] The second subcomponent is contained in the above dielectric composition within the above range, and thus the sintering start temperature is further lowered. Thus, the sintering density is further improved, and the relative dielectric constant is further improved. In addition, the second subcomponent is contained in the above dielectric composition within the above range, and thus an effect of improving the reduction resistance is obtained. As a result, the specific resistance is further improved.

[0026] The dielectric composition of the second aspect of the present application contains a main component and a first subcomponent represented by (Ba x Sr (1-x) ) m Ta4O 12 ,

[0027] The above m is 1.95 ≤ m ≤ 2.40,

[0028] The above first subcomponent is silicon and manganese,

[0029] The content of the main component in the dielectric composition is set to 100 mol parts,

[0030] The content of silicon in the dielectric composition is 5.0 to 20.0 mol parts in terms of SiO2,

[0031] The content of manganese in the dielectric composition is 5.0 to 40.0 mol parts in terms of MnO.

[0032] The dielectric composition of the second aspect of the present application has a high sintered density and a high relative dielectric constant even when sintered at a relatively low temperature (e.g., 1150 to 1250°C). Although the reason is not clear, it is considered to be the following reason. It is considered that, when m is within the above range, the dielectric composition contains a prescribed amount of silicon and manganese, and thus a low sintering start temperature is obtained. Thus, even when sintered at a relatively low temperature, a high sintered density is easily obtained, and the relative dielectric constant is also improved.

[0033] Preferably, the above m is 2.10 ≤ m ≤ 2.40. It is considered that, thereby, the wettability of the main component and the first subcomponent is improved, and a low sintering start temperature is obtained. Thus, a high sintered density is obtained even at a low temperature, and the relative dielectric constant is further improved.

[0034] Preferably, the above dielectric composition contains at least one selected from vanadium, magnesium, zirconium, tungsten, and a rare earth element as a second subcomponent,

[0035] The content of the main component in the dielectric composition is set to 100 mol parts,

[0036] The above dielectric composition contains 0.25 to 10.0 mol parts of at least one selected from vanadium, magnesium, zirconium, tungsten, and a rare earth element in terms of a prescribed oxide, wherein

[0037] The content of vanadium is in terms of V2O5,

[0038] The content of magnesium is in terms of MgO,

[0039] The content of zirconium is in terms of ZrO2,

[0040] The content of tungsten is in terms of WO3,

[0041] The content of the rare earth element represented by RE is in terms of RE2O3.

[0042] The second subcomponent is contained in the dielectric composition within the above range, whereby the sintering start temperature is further lowered. Thus, the sintering density is further improved, and the relative dielectric constant is further improved. In addition, the second subcomponent is contained in the dielectric composition within the above range, whereby an effect of improving the reduction resistance can be obtained. As a result, the specific resistance is further improved.

[0043] The dielectric composition of the present application preferably contains substantially no niobium, alkali metal, and lead.

[0044] As the dielectric composition exhibiting a high relative dielectric constant, (Sr, Ba)Nb2O6 containing niobium as a main component, (Na, K)NbO3 containing alkali metal, and Pb(Zr, Ti)O3 containing lead can be given.

[0045] The dielectric composition of the present application contains substantially no niobium, whereby oxygen defects are less likely to occur. In other words, the change in valence number is suppressed. Thus, it is considered that even if reduction firing is performed, the valence number is less likely to change, the decrease in specific resistance is suppressed, and a high specific resistance can be exhibited in a wide temperature range. In addition, for the same reason, it is considered that a low dielectric loss can be exhibited.

[0046] In addition, the dielectric composition of the present application contains substantially no alkali metal, and thus, the composition deviation of the dielectric composition and the contamination of the furnace due to the evaporation of alkali metal can be prevented.

[0047] Furthermore, the use of lead is restricted by RoHS (Restriction of Hazardous Substances Directive) and the like, but the dielectric composition of the present application contains substantially no lead.

[0048] In addition, the electronic component of the present application includes the above dielectric composition. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 is a schematic cross-sectional view of a multilayer ceramic capacitor of an embodiment of the present application.

[0050] Figure 2 is a schematic cross-sectional view of a multilayer ceramic capacitor of an embodiment of the present application. DETAILED DESCRIPTION

[0051] [First Embodiment]

[0052] [First Embodiment]

[0053] A multilayer ceramic capacitor 1 as an example of the electronic component of the present embodiment is as shown in Figure 1The layered ceramic capacitor 1 has an element main body 10 having a structure in which dielectric layers 2 and internal electrode layers 3 are alternately layered. A pair of external electrodes 4 are formed at both end portions of the element main body 10 so as to be in conduction with the internal electrode layers 3 alternately arranged inside the element main body 10. The shape of the element main body 10 is not particularly limited, and is generally set to a rectangular parallelepiped shape. Further, the size of the element main body 10 is also not particularly limited, and is set to an appropriate size according to the use.

[0054] <Dielectric Layer>

[0055] The dielectric layer 2 is composed of a dielectric composition of the present embodiment described later.

[0056] The thickness of each layer of the dielectric layer 2 (interlayer thickness) is not particularly limited, and can be set according to the desired characteristics, use, and the like. Generally, the interlayer thickness is preferably 30 μm or less, more preferably 15 μm or less, and further preferably 10 μm or less.

[0057] <Internal Electrode Layer>

[0058] In the present embodiment, the internal electrode layers 3 are layered in a manner in which each end portion is alternately exposed to the surface of the opposite two end faces of the element main body 10.

[0059] The conductive material contained in the internal electrode layers 3 is not particularly limited. As a metal used as the conductive material, for example, palladium, platinum, silver-palladium alloy, nickel, nickel-based alloy, copper, copper-based alloy, and the like can be given. Further, in nickel, nickel-based alloy, copper, or copper-based alloy, various trace components such as phosphorus and / or sulfur can be contained to an extent of 0.1 mass% or less. In addition, the internal electrode layers 3 can be formed using a paste for electrodes commercially available on the market. The thickness of the internal electrode layers 3 can be appropriately determined according to the use and the like.

[0060] <External Electrode>

[0061] The conductive material contained in the external electrode 4 is not particularly limited. A publicly known conductive material such as nickel, copper, tin, silver, palladium, platinum, gold, or an alloy thereof, a conductive resin, and the like can be used. The thickness of the external electrode 4 can be appropriately determined according to the use and the like.

[0062] <Dielectric Composition>

[0063] The dielectric composition constituting the dielectric layer 2 of the present embodiment contains at least either one of barium and strontium and tantalum as a main component.

[0064] The main component of the dielectric composition of the present embodiment preferably contains strontium, and more preferably contains both strontium and barium.

[0065] The main component of the dielectric composition of the present embodiment is composed of (Ba x Sr(1-x) m Ta4O 12 indicates.

[0066] x is preferably 0.75 or less, more preferably less than 0.75, and further preferably 0.1 to 0.50.

[0067] m is preferably 1.95≤m≤2.40, and more preferably 2.10≤m≤2.40.

[0068] The crystal system of the crystal of the main component of the dielectric composition of the present embodiment is not particularly limited, but is preferably tetragonal or orthorhombic, and more preferably tetragonal.

[0069] Further, in the present embodiment, when the elements other than oxygen contained in the dielectric composition are taken as 100 mol parts, the elements other than oxygen constituting the main component account for 50 to 99.5 mol parts.

[0070] In addition, the dielectric composition of the present embodiment is substantially free of niobium, alkali metals, and lead. "Substantially free of niobium, alkali metals, and lead" means that, when the elements other than oxygen contained in the dielectric composition are taken as 100 mol parts, the total of "niobium, alkali metals, and lead" is 10 mol parts or less, and is preferably 5 mol parts or less.

[0071] The dielectric composition of the present embodiment contains silicon and manganese as the first sub-component.

[0072] When the content of the main component in the dielectric composition is taken as 100 mol parts, the content of silicon in the dielectric composition is 5.0 to 20.0 mol parts, and is preferably 10.0 to 17.5 mol parts, in terms of SiO2. That is, the content of silicon is calculated in terms of an oxide in which the valence of silicon is taken as 4.

[0073] When the content of the main component in the dielectric composition is taken as 100 mol parts, the content of manganese in the dielectric composition is 1.0 to 4.5 mol parts, and is preferably 2.0 to 4.5 mol parts, in terms of MnO. That is, the content of manganese is calculated in terms of an oxide in which the valence of manganese is taken as 2.

[0074] Preferably, the dielectric composition of the present embodiment contains at least one selected from the group consisting of vanadium, magnesium, zirconium, and tungsten as the second sub-component.

[0075] Specifically, preferably, when the content of the main component in the dielectric composition is taken as 100 mol parts, the dielectric composition contains 0.25 to 10.0 mol parts of at least one selected from the group consisting of vanadium, magnesium, zirconium, and tungsten, in terms of a prescribed oxide.

[0076] ​The content of vanadium is converted into V2O5. That is, the content of vanadium is calculated as an oxide in which the valence of vanadium is set to 5.

[0077] The content of magnesium is converted into MgO. That is, the content of magnesium is calculated as an oxide in which the valence of magnesium is set to 2.

[0078] The content of zirconium is converted into ZrO2. That is, the content of zirconium is calculated as an oxide in which the valence of zirconium is set to 4.

[0079] The content of tungsten is converted into WO3. That is, the content of tungsten is calculated as an oxide in which the valence of tungsten is set to 6.

[0080] Also, the dielectric composition of the present embodiment can contain aluminum, calcium, chromium, rare earth elements, and the like in addition to the above-described main component, the first subcomponent, and the second subcomponent.

[0081] <Method for manufacturing a multilayer ceramic capacitor>

[0082] Next, an example of a method for manufacturing the multilayer ceramic capacitor 1 shown in FIG. 1 will be described. Figure 1

[0083] In the present embodiment, a powder of the main component and powders of the first subcomponent and the second subcomponent that constitute the above-described dielectric composition are prepared separately. The method for producing the powder of the main component is not particularly limited, and can be produced by a solid phase reaction method such as pre-sintering. As the raw material of each element of the powder of the main component and the powders of the first subcomponent and the second subcomponent, an oxide of each element can be used. In addition, various compounds that can obtain an oxide of each element by sintering can be used.

[0084] After the raw material of the powder of the main component and the powders of the first subcomponent and the second subcomponent are weighed in a prescribed ratio, wet mixing is performed for a prescribed time using a ball mill or the like. After the mixed powder is dried, heat treatment is performed in the range of 700 to 1300°C in the atmosphere to obtain pre-sintered powders of the main component and the first subcomponent and the second subcomponent. In addition, the pre-sintered powders can be pulverized for a prescribed time using a ball mill or the like.

[0085] Next, a paste for producing a green sheet is prepared. The obtained pre-sintered powders and a solvent are mixed and kneaded to become a coating material, and a paste for a dielectric layer is prepared. The binder and the solvent can be publicly known substances.

[0086] The paste for a dielectric layer can also contain an additive such as a plasticizer or a dispersant, as needed.

[0087] ​The paste for the internal electrode layer is obtained by kneading the raw material of the conductive material, the binder, and the solvent described above. The binder and the solvent can be any known material. The paste for the internal electrode layer can also contain additives such as a co-material or a plasticizer, as needed.

[0088] The paste for the external electrode can be prepared in the same manner as the paste for the internal electrode layer.

[0089] Using the respective pastes obtained, a green sheet and an internal electrode pattern are formed, and they are laminated to obtain a green sheet.

[0090] The green sheet obtained is subjected to binder removal treatment, as needed. The binder removal treatment conditions are, for example, preferably a holding temperature of 200 to 350°C.

[0091] After the binder removal treatment, the green sheet is fired to obtain the element body 10. In the present embodiment, the atmosphere during firing is not particularly limited, and can be air or a reducing atmosphere. In the present embodiment, the holding temperature during firing is, for example, 1200 to 1355°C.

[0092] After the firing, the element body 10 obtained is subjected to re-oxidation treatment (annealing), as needed. The annealing conditions are, for example, preferably an oxygen partial pressure during annealing that is higher than the oxygen partial pressure during firing, and a holding temperature of 1150°C or lower.

[0093] The dielectric composition constituting the dielectric layer 2 of the element body 10 obtained as described above is the dielectric composition described above. The element body 10 is subjected to end face polishing, a paste for the external electrode is applied, and firing is performed to form the external electrode 4. Then, a cover layer is formed on the surface of the external electrode 4 by plating or the like, as needed.

[0094] Thus, the multilayer ceramic capacitor 1 of the present embodiment is manufactured.

[0095] The dielectric composition of the present embodiment contains (Ba x Sr (1-x) ) m Ta4O 12 As the main component, m is within a prescribed range, and a prescribed amount of silicon and manganese are contained as the first sub-component, whereby even if the dielectric composition is fired at a relatively low temperature (for example, 1200 to 1355°C) to sinter it, a dielectric composition having a high sintered density and a high relative dielectric constant can be obtained.

[0096] Although the reason is not clear, it is considered as follows. It is considered that m is within the above range, and the dielectric composition contains a prescribed amount of silicon and manganese, whereby a sintering start temperature is lowered. Thus, even if sintering is performed at a low temperature, a high sintering density is easily obtained, and the relative dielectric constant is also improved.

[0097] In addition, according to the present embodiment, a dielectric composition exhibiting a high density, a high relative dielectric constant, a low dielectric loss, and a high specific resistance can be obtained without containing niobium, alkali metals, and lead.

[0098] The dielectric composition of the present embodiment containing tantalum and substantially not containing niobium has a tendency to exhibit a high relative dielectric constant, a low dielectric loss, and a high specific resistance compared to the conventional dielectric composition not containing tantalum and not containing niobium. As a reason thereof, it is considered that tantalum oxide (Ta2O5) is less likely to have oxygen defects compared to niobium oxide (Nb2O5).

[0099] The dielectric properties are properties premised on an insulator. Therefore, the dielectric composition is required to have a high resistance so that the dielectric composition does not become a semiconductor or a conductor. Moreover, as described above, tantalum oxide (Ta2O5) is less likely to have oxygen defects compared to niobium oxide (Nb2O5). In other words, the change in valence can be controlled. Therefore, it is considered that the decrease in specific resistance is suppressed, and a high specific resistance can be exhibited in a high temperature range. In addition, for the same reason, it is considered that a low dielectric loss can be exhibited.

[0100] [Second Embodiment]

[0101] [Thin Film Capacitor]

[0102] A schematic view of the thin film capacitor 11 of the present embodiment is shown in Figure 2 . Figure 2 The thin film capacitor 11 shown in the drawing has a lower electrode 112, a dielectric thin film 113, and an upper electrode 114 formed in this order on a substrate 111.

[0103] The material of the substrate 111 is not particularly limited, but a silicon single crystal substrate is excellent in terms of easiness of use and cost when used as the substrate 111. In the case where flexibility is valued, a nickel foil or a copper foil can be used as the substrate.

[0104] The material of the lower electrode 112 and the upper electrode 114 is not particularly limited, and functions as an electrode. Examples include platinum, silver, nickel, and the like. The thickness of the lower electrode 112 is not particularly limited, and is, for example, 0.01 to 10 μm. The thickness of the upper electrode 114 is also not particularly limited, and is, for example, 0.01 to 10 μm.

[0105] The composition and the crystal system of the main component of the dielectric composition constituting the dielectric thin film 113 of the present embodiment are the same as those of the first embodiment.

[0106] The thickness of the dielectric thin film 113 is not particularly limited, but is preferably 10 nm to 1 μm.

[0107] <Method for manufacturing thin film capacitor>

[0108] Next, a method for manufacturing the thin film capacitor 11 will be described.

[0109] The film formation method of the thin film which eventually becomes the dielectric thin film 113 is not particularly limited. Examples include vacuum evaporation, sputtering, PLD (pulsed laser deposition), MOCVD (metal organic chemical vapor deposition), MOD (metal organic decomposition), sol-gel, and CSD (chemical solution deposition).

[0110] In addition, the raw material used at the time of film formation sometimes contains a small amount of impurities or by-products, but as long as the amount is not significant to impair the performance of the thin film, there is no problem. In addition, the dielectric thin film 113 of the present embodiment can also contain a small amount of impurities or by-products to the extent that the performance is not significantly impaired.

[0111] In the present embodiment, a film formation method based on the PLD method will be described.

[0112] First, a silicon single crystal substrate is prepared as the substrate 111. Next, a film is formed in the order of SiO2, TiO2, and Pt on the silicon single crystal substrate, and a lower electrode 112 composed of Pt is formed. The method for forming the lower electrode 112 is not particularly limited. Examples include sputtering or CVD. x

[0113] Next, the dielectric thin film 113 is formed on the lower electrode 112 by the PLD method. In addition, in order to expose a part of the lower electrode 112, a metal mask can also be used to form a region where the film is not formed.

[0114] In the PLD method, first, a target containing the constituent elements of the dielectric thin film 113 targeted is disposed in a film formation chamber. Next, a pulsed laser is irradiated on the surface of the target. The surface of the target is instantaneously evaporated by the strong energy of the pulsed laser. Then, the evaporated material is deposited on the substrate disposed in opposition to the target to form the dielectric thin film 113.

[0115] ​There are no particular restrictions on the type of target material. In addition to metal oxide sintered bodies containing the constituent elements of the dielectric thin film 113 being produced, alloys and the like can also be used. Furthermore, it is preferable that the elements are evenly distributed in the target material, but uneven distribution is also permissible within the range that does not affect the quality of the resulting dielectric thin film 113.

[0116] The target material does not have to be a single one; multiple targets containing a portion of the constituent elements of the dielectric thin film 113 can be prepared for film formation. The shape of the target material is also not limited; it can be set to a shape suitable for the film formation apparatus used.

[0117] Furthermore, in the PLD method, to induce crystallization of the dielectric thin film 113, it is preferable to heat the substrate 111 using an infrared laser during film formation. The heating temperature of the substrate 111 varies depending on the constituent elements and composition of the dielectric thin film 113 and the substrate 111, for example, heating to 600–800°C for film formation. By setting the temperature of the substrate 111 to a suitable temperature, the dielectric thin film 113 can easily crystallize, and the occurrence of cracks during cooling can be prevented.

[0118] Finally, by forming an upper electrode 114 on the dielectric thin film 113, a thin-film capacitor 11 can be manufactured. Furthermore, the material of the upper electrode 114 is not particularly limited, and silver, gold, copper, etc., can be used. Additionally, the method of forming the upper electrode 114 is not particularly limited. For example, it can be formed by vapor deposition or sputtering.

[0119] [Third Implementation Method]

[0120] The third embodiment will now be described, but aspects not specifically described are the same as those in the first embodiment.

[0121] In this embodiment, when the content of the main component in the dielectric composition is set to 100 moles, the content of manganese in the dielectric composition is 5.0 to 40.0 moles, preferably 7.5 to 30.0 moles, converted from MnO.

[0122] Preferably, the dielectric composition of this embodiment contains at least one selected from vanadium, magnesium, zirconium, tungsten and rare earth elements as a second component.

[0123] Specifically, preferably, when the content of the main component in the dielectric composition is set to 100 moles, the dielectric composition contains 0.25 to 10.0 moles of at least one of vanadium, magnesium, zirconium, tungsten and rare earth elements, according to the specified oxide conversion.

[0124] Rare earth elements are represented by "RE". The content of rare earth elements (RE) is calculated using the RE₂O₃ conversion method. That is, the content of rare earth elements is calculated by converting them to oxides with the oxidation state of 3.

[0125] Examples of rare earth elements include Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, which can be used in combination of one or more.

[0126] In addition to the main component, the first secondary component, and the second secondary component described above, the dielectric composition of this embodiment may also contain aluminum, calcium, chromium, titanium, hafnium, molybdenum, etc.

[0127] In this embodiment, the holding temperature during firing is, for example, 1150–1250°C.

[0128] The dielectric composition of this embodiment contains (Ba x Sr (1-x) ) m Ta4O 12 As the main component, m contains a specified amount of silicon and manganese as the first secondary component within a specified range. Thus, even if the dielectric composition is sintered at a relatively lower temperature (e.g., 1150–1250 °C), a dielectric composition with high sintering density and high relative permittivity can be obtained.

[0129] Although the exact reason is unclear, it is considered to be as follows: Within the aforementioned range, the dielectric composition contains a specified amount of silicon and manganese, which results in a lower sintering start temperature. Consequently, even with relatively lower firing temperatures, a high sintering density is easily obtained, and the relative permittivity is also improved.

[0130] As described above, embodiments of the present invention have been explained, but the present invention is not limited to such embodiments. It is beyond doubt that the invention can be implemented in various different ways without departing from the spirit of the invention.

[0131] In the above embodiments, the case where the electronic component of the present invention is a multilayer ceramic capacitor has been described. However, the electronic component of the present invention is not limited to a multilayer ceramic capacitor, and can be any electronic component having the above-described dielectric composition.

[0132] For example, it can also be a single-plate type ceramic capacitor in which a pair of electrodes are formed on a single-layer dielectric substrate made of the above-described dielectric composition.

[0133] In addition to capacitors, the electronic components of the present invention can also be filters, duplexers, resonators, transmitters, antennas, etc.

[0134] Example

[0135] The present invention will now be described in more detail using examples and comparative examples. However, the present invention is not limited to the following examples.

[0136] As raw materials for the main components of the dielectric, powders of barium carbonate (BaCO3), strontium carbonate (SrCO3), and tantalum oxide (Ta2O5) were prepared. This was to ensure that the powders of (Ba...)... x Sr (1-x) ) m Ta4O 12 The composition of the principal component, x, is 0.5 in Tables 1, 2, 4 and 5, and as recorded in Table 3 or 6. Furthermore, m is as recorded in Tables 1 to 6, indicating that the raw materials of the prepared principal component were weighed.

[0137] In addition, as raw materials for the first and second sub-components of the dielectric composition, each raw material powder was prepared so that the contents of the first and second sub-components after firing were as described in Tables 1 to 6. The prepared raw materials for the first and second sub-components were weighed. Furthermore, "content of the first and second sub-components" refers to "the content of the first and second sub-components in the dielectric composition, converted according to the specified oxides, when the content of the main component in the dielectric composition is set to 100 moles".

[0138] Next, the weighed powders were wet-mixed using ion-exchanged water as the dispersion medium in a ball mill, and the mixture was dried to obtain a mixed raw material powder. Then, the obtained mixed raw material powder was heat-treated in air at a temperature of 900°C for 2 hours to obtain a pre-calcined powder.

[0139] The pre-calcined powder was wet-milled using ion-exchange water as a dispersion medium in a ball mill and then dried to obtain the dielectric raw material.

[0140] To obtain granulated powder, 10 parts by mass of an aqueous solution containing 6 parts by mass of polyvinyl alcohol resin as a binder are added to 100 parts by mass of the obtained dielectric raw material, and granulation is carried out.

[0141] The obtained granulated powder is then added to... In the mold, at 0.6 ton / cm 2 Pre-stamping is performed under pressure, and then at 1.2 ton / cm. 2 The pressure is used for main stamping to form a disc-shaped green body.

[0142] Next, the obtained green body is subjected to debinding treatment, firing and annealing under the following conditions to obtain the component body.

[0143] The adhesive removal treatment conditions are: temperature: 400℃, temperature holding time: 2 hours, atmosphere: air.

[0144] For the samples in Tables 1 to 3, the holding temperature during firing was set to 1350°C. For the samples in Tables 4 to 6, the holding temperature during firing was set to 1250°C. Other firing conditions included a temperature holding time of 2 hours and an atmosphere of humidified N2+H2 mixture (oxygen partial pressure 10). -12 (MPa). In addition, a humidifying agent is used in the humidification of the atmosphere gas during firing.

[0145] Annealing conditions: holding temperature: 1050℃, holding time: 2 hours, atmosphere: humidified N2 gas (oxygen partial pressure: 10). -7 (MPa). In addition, a wetting agent is used in the humidification of the atmosphere gas during annealing.

[0146] The sintering density, relative permittivity, and resistivity of the obtained sintered body (dielectric composition) were investigated using the following method. Furthermore, to measure the relative permittivity and resistivity, an In-Ga electrode was coated onto the aforementioned dielectric composition (sintered body) to obtain a disc-shaped ceramic capacitor sample (capacitor sample).

[0147] <Sintering Density>

[0148] The sintering density of the dielectric composition was measured as follows. First, the volume V of the dielectric composition was calculated. Next, the mass M of the disk-shaped dielectric composition was measured, and the sintering density of the dielectric composition was obtained by calculating M / V. The results are shown in Tables 1 to 6.

[0149] Relative permittivity

[0150] For the capacitor sample, the capacitance C was measured at room temperature (20°C) using a digital LCR meter (YHP 4284A) with an input frequency of 1 kHz and an input signal level (measurement voltage) of 1 Vrms. The relative permittivity was then calculated based on the thickness of the dielectric composition, the effective electrode area, and the measured capacitance C. The results are shown in Tables 1 to 6.

[0151] <Resistivity>

[0152] For the capacitor samples, the insulation resistance was measured at a reference temperature (25°C) using a digital ohmmeter (ADVANTEST R8340). The specific resistivity was calculated based on the obtained insulation resistance, effective electrode area, and dielectric composition thickness. The results are shown in Tables 1 to 6.

[0153] Table 1

[0154] Table 1

[0155]

[0156] Table 2

[0157] Table 2

[0158]

[0159] Table 3

[0160] Table 3

[0161]

[0162] Table 4

[0163] Table 4

[0164]

[0165] Table 5

[0166] Table 5

[0167]

[0168] Table 6

[0169] Table 6

[0170]

[0171] Based on Tables 1 to 3, it can be confirmed that: (Ba x Sr (1-x) ) m Ta4O 12 The m value is 1.95 ≤ m ≤ 2.40, the silicon content (converted to SiO2) is 5.0–20.0 mol parts, and the manganese content (converted to MnO) is 1.0–4.5 mol parts. Under these conditions (sample numbers 5–11, 16–21, 25–30, 32–47, 48–51), the sintering density is 6.50 g / cm³. 3 The above-mentioned properties have a relative permittivity of 70 or higher and a resistivity of 1.0 × 10⁻⁶. 11above.

[0172] Based on Tables 1 to 3, it can be confirmed that: (Ba x Sr (1-x) ) m Ta4O 12 The m content is 2.10 ≤ m ≤ 2.40, the silicon content (converted to SiO2) is 5.0–20.0 moles, and the manganese content (converted to MnO) is 1.0–4.5 moles. Under these conditions (sample numbers 8–11, 35–47, 48–51), the sintering density is 7.00 g / cm³. 3 The above have a relative permittivity of 100 or higher and a resistivity of 1.0 × 10⁻⁶. 11 above.

[0173] Based on Tables 1 to 3, it can be confirmed that: (Ba x Sr (1-x) ) m Ta4O 12 The m value is 2.10 ≤ m ≤ 2.40, the silicon content (converted to SiO2) is 5.0–20.0 mol parts, the manganese content (converted to MnO) is 1.0–4.5 mol parts, and the content of at least one of vanadium, magnesium, zirconium, and tungsten (converted to specified oxides) is 0.25–1.0 mol parts. Under these conditions (sample numbers 39–47), the sintered density is 7.00 g / cm³. 3 The above have a relative permittivity of 120 or higher and a specific resistivity of 1.0 × 10⁻⁶. 12 above.

[0174] Based on Tables 4 to 6, it can be confirmed that: (Ba x Sr (1-x) ) m Ta4O 12 The m value is 1.95 ≤ m ≤ 2.40. The silicon content, converted to SiO2, is 5.0–20.0 mol parts, and the manganese content, converted to MnO, is 5.0–40.0 mol parts. Under these conditions (sample numbers 15–111, 116–121, 125–132, 134–158, 161–164), the sintering density is 6.50 g / cm³. 3 The above-mentioned properties have a relative permittivity of 70 or higher and a resistivity of 1.0 × 10⁻⁶. 11 above.

[0175] Based on Tables 4 to 6, it can be confirmed that: (Ba x Sr (1-x) ) m Ta4O 12The m content is 2.10 ≤ m ≤ 2.40, the silicon content (converted to SiO2) is 5.0–20.0 moles, and the manganese content (converted to MnO) is 5.0–40.0 moles. Under these conditions (sample numbers 18–111, 137–158, 161–164), the sintering density is 7.00 g / cm³. 3 The above have a relative permittivity of 100 or higher and a resistivity of 1.0 × 10⁻⁶. 11 above.

[0176] Based on Tables 4 to 6, it can be confirmed that: (Ba x Sr (1-x) ) m Ta4O 12 The m value is 2.10 ≤ m ≤ 2.40, the silicon content (converted to SiO2) is 5.0–20.0 mol parts, the manganese content (converted to MnO) is 5.0–40.0 mol parts, and the content of at least one of vanadium, magnesium, zirconium, tungsten, and rare earth elements (converted to specified oxides) is 0.25–10.0 mol parts. Under these conditions (sample numbers 141–158), the sintered density is 7.00 g / cm³. 3 The above have a relative permittivity of 120 or higher and a specific resistivity of 1.0 × 10⁻⁶. 12 above.

[0177] Explanation of reference numerals in the attached figures

[0178] 1…Laminated ceramic capacitors

[0179] 10…Component Body

[0180] 2…Dielectric layer

[0181] 3…Inner Electrode Layer

[0182] 4…External Electrode

[0183] 11…film capacitors

[0184] 111…Substrate

[0185] 112…Lower Electrode

[0186] 113…Polycrystalline dielectric thin films

[0187] 114… Upper electrode.

Claims

1. A dielectric composition comprising a main component represented by (Ba x Sr (1-x) ) m Ta4O 12 and a first subcomponent, said m being 1.95 < m < 2.

40. x is 0 ≤ x ≤ 0.75, the first sub-component is silicon and manganese, when the content of the main component in the dielectric composition is set to 100 mol parts, the content of silicon in the dielectric composition is 5.0 to 20.0 mol parts in terms of SiO2, the content of manganese in the dielectric composition is 1.0 to 4.5 mol parts in terms of MnO.

2. The dielectric composition according to claim 1, wherein m is 2.10 ≤ m ≤ 2.

40.

3. The dielectric composition according to claim 1 or 2, wherein the dielectric composition contains at least one selected from the group consisting of vanadium, magnesium, zirconium, and tungsten as a second sub-component, when the content of the main component in the dielectric composition is set to 100 mol parts, the dielectric composition contains 0.25 to 1.0 mol parts of at least one selected from the group consisting of vanadium, magnesium, zirconium, and tungsten in terms of a prescribed oxide, wherein the content of vanadium is in terms of V2O5, the content of magnesium is in terms of MgO, the content of zirconium is in terms of ZrO2, the content of tungsten is in terms of WO3.

4. A dielectric composition comprising a main component represented by (Ba x Sr (1-x) ) m Ta4O 12 and a first subcomponent, said m being 1.95 < m < 2.

40. x is 0 ≤ x ≤ 0.75, the first sub-component is silicon and manganese, when the content of the main component in the dielectric composition is set to 100 mol parts, the content of silicon in the dielectric composition is 5.0 to 20.0 mol parts in terms of SiO2, the content of manganese in the dielectric composition is 5.0 to 40.0 mol parts in terms of MnO.

5. The dielectric composition according to claim 4, wherein m is 2.10 ≤ m ≤ 2.

40.

6. The dielectric composition according to claim 4 or 5, wherein the dielectric composition contains at least one selected from the group consisting of vanadium, magnesium, zirconium, tungsten, and a rare earth element as a second sub-component, when the content of the main component in the dielectric composition is set to 100 mol parts, the dielectric composition contains 0.25 to 10.0 mol parts of at least one selected from the group consisting of vanadium, magnesium, zirconium, tungsten, and a rare earth element in terms of a prescribed oxide, wherein the content of vanadium is in terms of V2O5, the content of magnesium is in terms of MgO, the content of zirconium is in terms of ZrO2, the content of tungsten is in terms of WO3, the content of the rare earth element represented by RE is in terms of RE2O3.

7. An electronic component comprising the dielectric composition according to any one of claims 1 to 6.

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