CN114956806B - Co-doped barium titanate ceramic dielectric material, preparation and application thereof - Google Patents

Co-doped barium titanate ceramic dielectric material, preparation and application thereof Download PDF

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CN114956806B
CN114956806B CN202111026878.9A CN202111026878A CN114956806B CN 114956806 B CN114956806 B CN 114956806B CN 202111026878 A CN202111026878 A CN 202111026878A CN 114956806 B CN114956806 B CN 114956806B
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barium titanate
dielectric material
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doped barium
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CN114956806A (en
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张蕾
厉琨
于淑会
孙蓉
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Shenzhen Institute of Advanced Electronic Materials
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Abstract

The invention discloses a co-doped barium titanate ceramic dielectric material, a preparation method and application thereof, and belongs to the technical field of ceramic media. Wherein the main material of the co-doped barium titanate ceramic dielectric material is 93 to 94mol percent BaTiO 3 The doping material is 6 to 7mol percent of SiO 2 、MgO、Al 2 O 3 、V 2 O 5 、Sc 2 O 3 、Dy 2 O 3 、Ho 2 O 3 、Yb 2 O 3 And Tm 2 O 3 . The invention also discloses a multilayer ceramic capacitor, the dielectric constant of which is between 4700 and 4800, the room temperature resistivity is about 9Ω.m, and the temperature characteristic meets the X6T requirement of EIA. The co-doped barium titanate ceramic dielectric material and the capacitor provided by the invention have the advantages of simple preparation process, no toxic substances, good matching with internal electrodes of base metals such as nickel, compact ceramic body, small crystal grains, few defects and wide application.

Description

Co-doped barium titanate ceramic dielectric material, preparation and application thereof
Technical Field
The invention relates to the technical field of ceramic media, in particular to a co-doped barium titanate ceramic dielectric material, and preparation and application thereof.
Background
Multilayer ceramic capacitors (MLCCs) are widely used in communication infrastructure circuits in the fields of communication equipment, automotive electronics, industrial machinery, medical equipment, and the like. It may be used as a power bypass capacitor such as a liquid crystal module (liquid crystal driving voltage line), an LSI/IC/OP amplifier of high power supply voltage, or as a smoothing capacitor such as a DC-DC converter (input and output), a switching power supply (secondary side), or the like.
In recent years, miniaturization of mobile electronic devices has led to the development of MLCCs in the direction of miniaturization and large capacity. Barium titanate (BaTiO) 3 ) The matrix material of class II capacitors in MLCCs has a high dielectric constant, but in order to obtain a barium titanate-based MLCC with a large capacity, the number of layers needs to be increased, resulting in a significant decrease in the reliability of the MLCC. In addition, the dielectric constant of barium titanate fluctuates greatly at-90 ℃, 0 ℃ and 125 ℃, and this characteristic limits the application range of barium titanate. The dielectric materials of class II capacitors have a temperature coefficient of capacitance of X5R, X, 6T, X T, etc., and as mentioned in the American Electronic Industry Association (EIA) capacitor Specification, the rate of change of capacitance must be between +22% and-33% at temperatures between-55 ℃ and 105 ℃.
The stability of barium titanate when the temperature is changed can influence the dielectric property, the dielectric property of the barium titanate is generally mutated near the Curie temperature, and in order to overcome the problems, the barium titanate powder raw material needs to be modified, on the one hand, the barium titanate powder raw material is modified, on the other hand, ultra-pure superfine powder with good dispersibility is prepared, and the nano effect is utilized to change the performance.
Disclosure of Invention
Aiming at the technical problems, the invention provides a co-doped barium titanate ceramic dielectric material with high dielectric constant and Gao Rongwen coefficient, and a preparation method and application thereof. The invention selects the oxide of rare earth element as the doping agent to modify barium titanate, and adds doping materials such as sintering aid and the like to refine particles, thus preparing the fine-grain ceramic which has stable capacitance characteristic and is easier to laminate.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the first aspect of the invention provides a co-doped barium titanate ceramic dielectric material, wherein the co-doped barium titanate is BaTiO 3 Is a main material, the addition amount of the main material is 93 to 94mol percent based on the co-doped barium titanate ceramic dielectric material, and SiO is used 2 、MgO、Al 2 O 3 、V 2 O 5 And rare earth element oxide as doping material, wherein the rare earth element oxide is Sc 2 O 3 、Dy 2 O 3 、Ho 2 O 3 、Yb 2 O 3 And Tm 2 O 3 Based on the co-doped barium titanate ceramic dielectric materialThe total addition amount of (2) is 6 to 7mol%.
Preferably, the host material BaTiO 3 The particle size of (2) is 150-200 nm.
Preferably, based on the co-doped barium titanate ceramic dielectric material, the SiO 2 The amount of (C) added is 1.0 to 1.8mol%, for example, 1.0mol%, 1.1mol%, 1.2mol%, 1.3mol%, 1.4mol%, 1.5mol%, 1.6mol%, 1.7mol%, 1.8mol%, or any value therebetween.
Preferably, the amount of MgO added is 0.5 to 1.0mol%, for example, 0.5mol%, 0.6mol%, 0.7mol%, 0.8mol%, 0.9mol%, 1.0mol%, or any value therebetween.
Preferably, the Al 2 O 3 The amount of (C) added is 0.8 to 2.0mol%, for example, 0.8mol%, 0.9mol%, 1.0mol%, 1.2mol%, 1.5mol%, 1.8mol%, 2.0mol%, or any value therebetween.
Preferably, the V 2 O 5 The amount of (C) added is 0.5 to 0.9mol%, for example, 0.5mol%, 0.6mol%, 0.7mol%, 0.8mol%, 0.9mol%, or any value therebetween.
Preferably, the rare earth element oxide is added in an amount based on the co-doped barium titanate ceramic dielectric material:
preferably, the Sc 2 O 3 The amount of (C) added is 0.3 to 0.6mol%, for example, 0.3mol%, 0.4mol%, 0.5mol%, 0.6mol%, or any value therebetween.
Preferably, the Dy 2 O 3 The amount of (C) added is 0.4 to 0.7mol%, for example, 0.4mol%, 0.5mol%, 0.6mol%, 0.7mol%, or any value therebetween.
Preferably, the Ho 2 O 3 The amount of (C) added is 0.3 to 0.6mol%, for example, 0.3mol%, 0.4mol%, 0.5mol%, 0.6mol%, or any value therebetween.
Preferably, the Yb 2 O 3 The amount of (C) added is 0.2 to 0.5mol%, for example, 0.2mol%, 0.3mol%, 0.4mol%, 0.5mol%, or any value therebetween.
Preferably, the Tm 2 O 3 The amount of (C) added is 0.2 to 0.5mol%, for example, 0.2mol%, 0.3mol%, 0.4mol%, 0.5mol%, or any value therebetween.
The second aspect of the present invention provides a method for preparing the co-doped barium titanate ceramic dielectric material, comprising the steps of: and carrying out wet ball milling on the main material barium titanate and the doping material, and drying to obtain the co-doped barium titanate ceramic dielectric material.
In a third aspect, the present invention provides a use of the co-doped barium titanate ceramic dielectric material in the preparation of an electronic component, preferably a multilayer ceramic capacitor.
A fourth aspect of the present invention provides a multilayer ceramic capacitor, wherein the dielectric material of the multilayer ceramic capacitor is the above co-doped barium titanate ceramic dielectric material; and sintering the co-doped barium titanate ceramic dielectric material with an inner metal electrode in a reducing atmosphere to obtain the insulating ceramic dielectric layer of the multilayer ceramic capacitor.
Preferably, the sintering temperature is 1220-1280 ℃; the grain size of the ceramic medium of the multilayer ceramic capacitor is 180-250 nm; the number of layers of the multilayer ceramic capacitor is 400-800.
In some specific embodiments, the sintering temperature is 1220 ℃, 1230 ℃, 1240 ℃, 1250 ℃, 1260 ℃, 1270 ℃, 1280 ℃ or any number of temperatures therebetween.
In some specific embodiments, the ceramic dielectric of the multilayer ceramic capacitor has a grain size of 180nm, 190nm, 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, or any number therebetween.
In some specific embodiments, the multilayer ceramic capacitor has a number of layers of 400, 500, 600, 700, 800 or any number therebetween.
Preferably, the multilayer ceramic capacitor has a dielectric constant of 4700 to 4800 and a resistivity of 8.4 to 9.1 Ω·m at 25 ℃.
Preferably, in the technical scheme of the invention, the capacitance change rate of the multilayer ceramic capacitor is between +22% and-33% at the temperature of-55 ℃ to 105 ℃.
In some specific embodiments, the multilayer ceramic capacitor has a dielectric constant of 4700, 4710, 4720, 4730, 4740, 4750, 4760, 4770, 4780, 4790, 4800, or any value therebetween, and a resistivity of 8.4 Ω -m, 8.5 Ω -m, 8.6 Ω -m, 8.7 Ω -m, 8.8 Ω -m, 8.9 Ω -m, 9.0 Ω -m, 9.1 Ω -m, or any value therebetween, at 25 ℃.
The technical scheme has the following advantages or beneficial effects:
the invention uses BaTiO 3 As a host material, a barium titanate ceramic dielectric material having a high dielectric constant and Gao Rongwen coefficient is prepared by optimizing the proportion of the dopant material. Wherein SiO is added 2 As sintering aid, the sintering temperature is reduced and widened, and the growth of crystal grains of ceramic particles in the sintering process is prevented; mgO is added to refine grains and promote BaTiO 3 The density of the ceramic is improved in the mass transfer process; and SiO 2 With Al 2 O 3 In addition, the liquid phase on the surface of the inner electrode can prevent metal elements from diffusing to a medium layer, so that the reliability of the MLCC is enhanced, and the superiority of the invention in the application field of the MLCC is increased; to prevent Ti 4+ Reduction of ions to Ti during sintering in a reducing atmosphere 3+ Generating oxygen vacancies, adding V 2 O 5 The valence-variable V element is substituted for Ti in Barium Titanate (BT), so that the generation of oxygen vacancies is inhibited, and the remnant polarization is improved. The invention selects Sc 2 O 3 、Dy 2 O 3 、Ho 2 O 3 、Yb 2 O 3 、Tm 2 O 3 The rare earth elements are used as doping materials to form a core-shell structure, so that the influence of temperature on the capacitor is stabilized.
The multilayer ceramic capacitor MLCC prepared by sintering the co-doped barium titanate ceramic dielectric material in a reducing atmosphere has high dielectric constant and Gao Rongwen coefficient, wherein the dielectric constant is between 4700 and 4800, the room temperature resistivity can reach 9 omega-m, and the requirement of X6T temperature characteristic, namely the capacitance change rate is between +22% and-33% at the temperature of-55 ℃ to 105 ℃, can be met. The co-doped barium titanate ceramic dielectric material and the capacitor provided by the invention have the advantages of simple preparation process, no toxic substances, good matching with internal electrodes of base metals such as nickel, compact ceramic body, small crystal grains, few defects and wide application prospect.
Drawings
Fig. 1: scanning electron microscopy of MLCC samples in example 1 of the present invention.
Fig. 2: scanning electron microscopy of the MLCC sample in example 2 of the present invention.
Fig. 3: grain size distribution of the MLCC sample in example 1 of the present invention.
Fig. 4: grain size distribution of the MLCC sample in example 2 of the present invention.
Fig. 5: MLCC sample and raw material high-purity BaTiO in example 1 of the present invention 3 The dielectric constant of the powder is compared with the temperature.
Fig. 6: MLCC sample and raw material high-purity BaTiO in example 2 of the present invention 3 The dielectric constant of the powder is compared with the temperature.
Fig. 7: the MLCC sample in example 1 of the present invention is a schematic diagram showing the ratio of capacitance change versus temperature.
Fig. 8: the MLCC sample in example 2 of the present invention is a schematic diagram showing the ratio of capacitance change versus temperature.
Fig. 9: schematic of the rate of change of capacitance versus temperature for the MLCC sample of example 1 of the present invention at each test frequency.
Fig. 10: a schematic diagram of the rate of change of capacitance versus temperature for the MLCC samples of example 2 of the present invention at each test frequency.
Detailed Description
The following examples are only some, but not all, of the examples of the invention. Accordingly, the detailed description of the embodiments of the invention provided below is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by a person skilled in the art without making any inventive effort, are intended to fall within the scope of the present invention.
The invention aims to design a ceramic dielectric material with high dielectric constant and Gao Rongwen coefficient, which uses BaTiO 3 As a main material, siO 2 、MgO、Al 2 O 3 、V 2 O 5 、Sc 2 O 3 、Dy 2 O 3 、Ho 2 O 3 、、Yb 2 O 3 、Tm 2 O 3 Is a doped material, wherein, a host material BaTiO 3 The addition amount of the (C) is 93-94 mol%, and the total addition amount of the doping materials is 6-7 mol%.
Wherein, the main material BaTiO 3 The particle size of (2) is 150-200 nm.
In the invention, the common BaTiO is adopted 3 The main material can reduce the complexity of the process and save the cost. Empirically, baTiO 3 After sintering the nano particles to prepare the multilayer ceramic capacitor (MLCC), the grain size grows up to 20 to 35 percent, so that the main body BaTiO is controlled 3 The grain size of the ceramic is 150-200 nm to obtain the final ceramic grains of 180-250 nm.
The invention adopts an amphoteric doping mode, and adopts rare earth element Sc, dy, ho, yb, tm as a donor doped with Ba bit and an acceptor doped with Ti bit of the BT material. When the rare earth element is doped at the Ba site as a donor, the curie temperature decreases and the dielectric constant increases. In addition, rare earth elements can influence the formation of BT crystal grains to form a core-shell structure, so that the peak value at the Curie temperature is reduced, and the capacity temperature change rate can be obviously reduced.
In the periodic table of chemical elements, dy, ho, and Tm are located adjacently, the radii of +3 valent ions are closest, and substitution mechanisms in BT crystals are substantially the same. The larger ion radius after Ti is replaced can increase the BT lattice parameter, so that larger tetragonality is obtained, the dielectric constant is improved, and the larger tetragonality can increase the capacitance loss rate of the MLCC under direct current bias. When Dy is 3+ When substituting Ba position, ti 4+ Conversion to Ti 3+ And form conductive electrons to maintain charge neutrality, such additional electrons helping to increase dielectric constant.
The "core-shell" structure formed by doping Dy element can improve the capacitance change rate of the low-temperature end, but is easy to damage at higher sintering temperature. And Tm 3+ The ion-formed 'core-shell' structure can improve the stability at high temperature, so that Dy with high concentration is in a Dy element and Tm element co-doped system 2 O 3 And a low concentration of Tm 2 O 3 The dielectric constant and the temperature stability of the co-doped BT can be improved at the same time.
The formation of the "core-shell" structure in BT-MgO-rare earth oxide systems depends on the substitution rate of rare earth ions for Ba sites. The Dy, ho elements have a smaller ionic radius than other rare earth elements than the larger radius ion doping, requiring less MgO to suppress grain growth and form a "core-shell" structure. And, ho with smaller radius 3+ Ions can be dissolved at two sites of Ba and Ti sites, so that the tetragonality can be controlled without greatly increasing, and the loss rate under direct current bias can be controlled. In addition, the solid solubility of rare earth ions with small radius is reduced, the thickness of a shell layer is conveniently controlled in a sintering system, so that a larger core volume ratio is obtained, a medium temperature curve in a high temperature section is further improved, and the dielectric constant is further improved after peak pressing. When Dy and Ho are doped together, proper sintering temperature is controlled, a shell layer with a certain thickness can be obtained at a lower sintering temperature, and the effect of adjusting the proportion of the core shell can be achieved.
The Sc element forms a 'core-shell' structure of the grain, and in addition to improving the temperature stability of the dielectric properties, sc 2 O 3 The existence of the (C) can also improve the insulation resistance at normal temperature and reduce the dielectric loss. However, the addition amount of Sc element should not be excessive, otherwise the stability of MLCC at high temperature may be reduced. Due to Sc 2 O 3 Is relatively expensive, so Yb can be used 2 O 3 Instead of, but Yb 3+ Is relatively low in solid solubility, and excessive incorporation may react with Ti displaced by other Ti site dopants to produce pyrochlore phase Yb 2 Ti 2 O 7 Therefore, it is necessary to control the doping amount of Yb, and only a part of Sc element can be replaced. The doping effect of the rare earth elements is not single effect, but mutually influences and assists, so that the doping concentration of each rare earth element needs to be reasonably controlled, and the effect of each rare earth element in a co-doping system is maximized.
Further, in the preferred embodiment of the present invention, siO is included in the doping material 2 The addition amount of MgO is 1.0 to 1.8mol percent, the addition amount of MgO is 0.5 to 1.0mol percent, and Al is added 2 O 3 The addition amount of (C) is 0.8-2.0 mol%, V 2 O 5 The addition amount of Sc is 0.5 to 0.9mol percent 2 O 3 The addition amount of Dy is 0.3-0.6 mol% 2 O 3 The addition amount of (C) is 0.4-0.7 mol%, ho 2 O 3 The addition amount of Yb is 0.3 to 0.6mol percent 2 O 3 The addition amount of (C) is 0.2-0.5 mol%, tm 2 O 3 The addition amount of (C) is 0.2-0.5 mol%.
Further, in a preferred embodiment of the present invention, the method for preparing the co-doped barium titanate ceramic dielectric material comprises the steps of: mixing a main material and a doped material according to a proportion, adopting zirconia balls as ball milling media, performing wet ball milling, and drying to obtain the co-doped barium titanate ceramic dielectric material.
Further, in the preferred embodiment of the invention, the co-doped barium titanate ceramic dielectric material is sintered with the metal inner electrode for 2-4 hours in the reducing atmosphere at 1220-1280 ℃ to prepare the insulating ceramic dielectric layer of the multilayer ceramic capacitor. The ceramic can be well sintered and densified and the grain size can be well controlled within the temperature range of 1220-1280 ℃. Sintering temperature is too low, siO 2 、Al 2 O 3 The liquid phase is not easy to form in the isodoped material, so that the ceramic is not sintered compactly enough, and the dielectric constant is reduced; too high a sintering temperature can cause excessive growth of ceramic grains, affecting the dielectric constant and service life of the MLCC test sample.
Further, in the preferred embodiment of the present invention, the grain size of the ceramic dielectric of the multilayer ceramic capacitor is 180 to 250nm. Correspondingly, the number of layers of the multilayer ceramic capacitor is 400-800.
Further, in the preferred embodiment of the present invention, the dielectric constant of the finished multilayer ceramic capacitor is between 4700 and 4800 at 25 ℃.
Further, in the preferred embodiment of the invention, the capacitance change rate of the prepared multilayer ceramic capacitor is between +22% and-33% at the temperature of-55 ℃ to 105 ℃ so as to meet the X6T requirement of EIA.
In the following examples, the co-doped barium titanate ceramic dielectric material and the MLCC were prepared as follows:
(1) Selecting high-purity BaTiO with particle size of 150-200 nm 3 Mixing the powder with various doping materials according to a proportion, adopting zirconia balls as ball milling media, placing the zirconia balls in a ball mill, performing wet ball milling for 20 hours, and drying after ball milling is finished to obtain ceramic dielectric material powder.
(2) Preparation of MLCC samples: the ceramic dielectric material powder obtained by the method is prepared into slurry, cast into a membrane with the size of 1.2 mu m, and then electrode printing, lamination, pressing and cutting are carried out to form a green body with a certain shape and size. Wherein, nickel paste is used as an internal electrode, and the number of the laminated layers is 600. The green sheet was subjected to a reducing atmosphere (1%H 2 +99％N 2 ) Sintering for 2-4 h at 1220-1280 ℃, then cooling to 950-1100 ℃ for annealing treatment, and cooling to 25 ℃ for sintering to form the monolithic ceramic body. Then copper paste is adhered to two ends of the porcelain body in a copper-adhering mode, a copper electrode firmly combined with the porcelain body is formed by sintering at 800-950 ℃, a nickel layer is electroplated on the surface of the copper electrode, and a tin layer is electroplated for the second time, so that the MLCC sample is prepared.
The features and capabilities of the present invention are described in further detail below in connection with examples.
Example 1
In this example, the host material BaTiO 3 The particle size of the powder is 150nm, the sintering temperature in the reducing atmosphere is 1220 ℃, the time is 2h, the temperature is reduced to 950 ℃ for annealing treatment for 2h, and the copper dipping and sintering temperature is 900 ℃.
Table 1 the formulation of example 1
Figure BDA0003243621750000081
Table 2 table of the results of the performance test of example 1
Figure BDA0003243621750000082
Figure BDA0003243621750000091
Example 2
In this example, the host material BaTiO 3 The particle size of the powder is 200nm, the sintering temperature in the reducing atmosphere is 1240 ℃, the time is 2h, the temperature is reduced to 950 ℃ for annealing treatment for 2h, and the copper dipping and sintering temperature is 900 ℃.
Table 3 formulation table of example 2
Figure BDA0003243621750000092
Table 4 table of the results of the performance test of example 2
Figure BDA0003243621750000093
As shown in tables 2 and 4, the barium titanate ceramic dielectric material prepared by the above process can form an adjustable system ceramic dielectric material with dielectric constant between 4700 and 4800 at 25 ℃ and resistivity up to-9 omega m by adjusting the proportion of the main body and the modified additive within the temperature range of 1220-1280 ℃.
In addition, the characterization results of the scanning electron microscope (FESEM) of the embodiment 1 and the embodiment 2 are shown in the figure 1 and the figure 2, and the samples prepared in the embodiment 1 and the embodiment 2 have good compactness and no obvious holes.
The distribution of ceramic grain size according to SEM image statistics is shown in fig. 3 and 4 (among them, 381 grains are counted in example 1, 328 grains are counted in example 2): the MLCC prepared in examples 1 and 2 of the present invention has regular ceramic grain size distribution and average grain size of about 214nm.
Comparison of MLCC samples prepared in examples 1 and 2 of the present invention with high purity BaTiO corresponding to the examples 3 The relationship between the dielectric constant and the temperature of the powder is shown in fig. 5 and 6: the sample prepared by the embodiment of the invention improves the high-purity BaTiO of the raw material powder 3 And well stabilizes the influence of a drastic change in dielectric constant caused by temperature.
The relationship between the rate of change of capacitance constant and temperature of the MLCC samples prepared in comparative examples 1 and 2 is shown in FIGS. 7 and 8: the capacitance change rate is between +22% and-33% at the temperature of-55 ℃ to 105 ℃, and meets the X6T requirement of EIA.
In order to expand the application field of the invention, the samples prepared in example 1 and example 2 were tested in particular for the rate of change of the temperature between 1 and 10 kHz. The dielectric constant change rate and the temperature of the sample prepared by the embodiment of the invention under each test frequency are shown in fig. 9 and 10: under various test frequencies between 1 and 10kHz, the capacitance change rate of the samples prepared by the embodiment of the invention is between +22% and-33% at the temperature of between-55 ℃ and 105 ℃, so that the X6T requirement of EIA is met.
The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the invention, and all equivalent changes made by the specification and drawings of the present invention, or direct or indirect application in other related technical fields, are included in the scope of the present invention.

Claims (9)

1. The co-doped barium titanate ceramic dielectric material is characterized in that the co-doped barium titanate ceramic dielectric material adopts BaTiO 3 The material is a main material, and the addition amount of the main material is 93-94 mol% based on the co-doped barium titanate ceramic dielectric material; in SiO form 2 、MgO、Al 2 O 3 、V 2 O 5 And oxides of rare earth elementsIs a doped material, the oxide of the rare earth element is Sc 2 O 3 、Dy 2 O 3 、Ho 2 O 3 、Yb 2 O 3 And Tm 2 O 3 The total addition amount of the doped material is 6-7 mol% based on the co-doped barium titanate ceramic dielectric material;
based on the co-doped barium titanate ceramic dielectric material, the SiO 2 The addition amount of (2) is 1.2-1.8 mol%; the addition amount of MgO is 0.6-0.9 mol%; the Al is 2 O 3 The addition amount of (2) is 0.9-1.8 mol%; the V is 2 O 5 The addition amount of (2) is 0.6-0.9 mol%;
the addition amount of the rare earth element oxide based on the co-doped barium titanate ceramic dielectric material is that the Sc 2 O 3 The addition amount of (C) is 0.4-0.5 mol%; the Dy is 2 O 3 The addition amount of (C) is 0.5-0.6 mol%; the Ho 2 O 3 The addition amount of (C) is 0.4-0.5 mol%; the Yb is 2 O 3 The addition amount of (C) is 0.2-0.5 mol%; the Tm is 2 O 3 The addition amount of (C) is 0.2-0.5 mol%;
the main material BaTiO 3 The particle size of the particles is 150-200 nm.
2. The method for preparing a co-doped barium titanate ceramic dielectric material according to claim 1, comprising the steps of: and carrying out wet ball milling on the main material barium titanate and the doping material, and drying to obtain the co-doped barium titanate ceramic dielectric material.
3. Use of a co-doped barium titanate ceramic dielectric material according to claim 1 for the manufacture of an electronic component, wherein the electronic component is a multilayer ceramic capacitor.
4. A multilayer ceramic capacitor, wherein the dielectric material of the multilayer ceramic capacitor is the co-doped barium titanate ceramic dielectric material of claim 1; and sintering the co-doped barium titanate ceramic dielectric material with an inner metal electrode in a reducing atmosphere to obtain the insulating ceramic dielectric layer of the multilayer ceramic capacitor.
5. The multilayer ceramic capacitor according to claim 4, wherein the sintering temperature is 1220 ℃ to 1280 ℃.
6. The multilayer ceramic capacitor according to claim 4, wherein the grain size of the ceramic medium of the multilayer ceramic capacitor is 180-250 nm.
7. The multilayer ceramic capacitor according to claim 4, wherein the number of stacked layers of the multilayer ceramic capacitor is 400 to 800.
8. The multilayer ceramic capacitor according to claim 4, wherein the multilayer ceramic capacitor has a dielectric constant of 4700 to 4800 and a resistivity of 8.4 to 9.1 Ω -m at 25 ℃.
9. The multilayer ceramic capacitor of claim 4, wherein the multilayer ceramic capacitor has a capacitance change rate between +22% and-33% at-55 ℃ to 105 ℃.
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