KR20050086151A - Sintering inhibitor for inner electrode paste of multilayer ceramic capacitor, method for manufacturing inner electrode paste for multilayer ceramic capacitor having the sintering inhibitor and multilayer ceramic capacitor - Google Patents

Abstract

The present invention relates to a multilayer ceramic capacitor using a conductive Ni internal electrode paste in a dielectric composition having a reduction resistance, and has excellent dielectric properties even at high temperature and low frequency, high reliability even when the dielectric layer is thin, and small capacitance temperature coefficient. An object of the present invention is to provide a multilayer ceramic capacitor having.

The present invention relates to a common material for an internal electrode of a multilayer ceramic capacitor comprising an internal electrode containing a dielectric and a common material, the same as the above dielectric composition; When the composition is expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], the values of x, y and m are 0.55≤x≤0.70 and 0.3≤, respectively. Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O ₃ (BCG) as a main component having a range of y ≦ 0.4, 0.9960 ≦ m ≦ 1.004, and as subcomponents, and the Mn ₃ O ₄ and Al ₂ O ₃ and BCG content of the multilayer ceramic capacitor, characterized in that the Mn ₃ O ₄ : 0.5 ~ 1.5%, Al ₂ O ₃ : 0.1 ~ 0.8% and BCG: 2.0 ~ 3.0% with respect to 100 mol of the main component, respectively The internal electrode common material, the manufacturing method of the internal electrode paste for laminated ceramic capacitors containing this common material, and laminated ceramic capacitor are made into the summary.

Description

Sintering Inhibitor for Inner Electrode Paste of Multilayer Ceramic Capacitor, Method for Manufacturing Inner Electrode Paste for Multilayer Ceramic Capacitor having the Sintering Inhibitor and Multilayer Ceramic Capacitor}

The present invention relates to a multilayer ceramic capacitor including an internal electrode formed by using a dielectric and a conductive Ni internal electrode paste made of a composition having reduction resistance, and more particularly, an internal electrode paste common material using the same composition as the dielectric, A method for producing an internal electrode paste for a multilayer ceramic capacitor containing this common material and a multilayer ceramic capacitor are disclosed.

In recent years, as electronic devices become smaller and lighter, surface-mount substrates have increased, and miniaturization and thinning of chip components mounted thereon have been required.

Capacitors, one of the chip components, have been used for many purposes in analog and digital electronic circuits.

The multilayer ceramic capacitor (hereinafter referred to as "MLCC") is a chip component capacitor capable of surface mounting and has been developed for ceramic materials, and has been used mainly in mobile devices because of its advantages such as excellent high frequency characteristics and high reliability.

Further, with the advance of Ni electrode material and the electrode stacking technology, low cost and multi-layering have progressed, which makes it possible to increase the capacity of the capacitor.

Therefore, the allowable capacitance range of the multilayer ceramic capacitor extends to the capacitive region of tantalum and alumina electrolytic capacitors so that it can be replaced with such capacitors. In the future, the MLCC is expected to increase its usage and increase its demand. to be.

In the multilayer ceramic capacitor, as shown in FIG. 1, the internal electrode 2 is formed on the dielectric layer sheet 1 using an internal electrode paste by a printing method or the like, and a plurality of dielectric layers on which the internal electrodes are printed are laminated. The internal electrode of the body weight and the dielectric layer are fired at the same time, and then connected to the internal electrode to form an external electrode 3 for exerting capacitance, and the plating layers 4 and 5 are formed to prevent problems during soldering. It is manufactured by.

Pd and Pd alloys have been used as the conductive material of the internal electrode layers, but in recent years, the use of base metals such as Ni and Ni alloys, which are relatively inexpensive, has been increasing.

In the case of using a non-metal such as Ni as the conductive material of the internal electrode (layer), since the internal electrode layer is oxidized when firing in the air, simultaneous firing of the dielectric material and the internal electrode layer should be performed in a reducing atmosphere.

As described above, when the dielectric and the like are simultaneously baked in a reducing atmosphere, the dielectric layer is reduced to lower specific resistance.

Therefore, in order to solve this problem, a dielectric material having reduction resistance has been proposed.

Examples of the above-mentioned reduction resistant dielectric materials include those disclosed in Japanese Patent Laid-Open No. 63-126117, Japanese Patent Laid-Open No. 63-289709, Japanese Patent Laid-Open No. 5-217426, and Japanese Patent Laid-Open No. 10-335169. These reducing-resistant dielectric materials are those capable of co-firing with nonmetals such as Ni or Cu by adding sub-components such as silica and Li-based glass to the (Ca, Sr) (Ti, Zr) O ₃ based dielectric composition. to be.

However, the dielectric material is found to have a frequency dependence on relative dielectric constant, dielectric loss, etc. by the addition of Li glass and the like, and there is a problem that the dielectric constant and dielectric loss increase remarkably at high temperatures of 100 ° C. or higher and hundreds of Hz.

Further, in the case of the dielectric material, when the dielectric layer is thinned, there is a problem in that the lifetime of the IR is shortened and the reliability is lowered.

In addition, there is a small change in the temperature of the capacitance, that is, the capacity temperature coefficient is small, and there is an increasing demand for a temperature compensation multilayer capacitor that can be arbitrarily controlled in the range of -870 to -630 ppm / 占 폚.

In other words, there is a need for dielectric and internal electrode paste materials for providing capacitors with small capacitance temperature coefficients.

MEANS TO SOLVE THE PROBLEM The present inventors made the research and experiment in order to improve the problem of the said prior art, and respond to the demand of the industry, and based on the result, the present invention proposes the composition of the common material contained in the internal electrode. By the same composition as the dielectric, the internal electrodes of the multilayer ceramic capacitor are excellent in dielectric properties even at high and low frequencies, and have a high reliability even when the dielectric layer is thinned and enable the production of a multilayer ceramic capacitor having a small capacitance temperature coefficient. It is an object of the present invention to provide a paste material and a method for producing an internal electrode paste for a multilayer ceramic capacitor containing the material.

In addition, another object of the present invention is to provide a multilayer ceramic capacitor having excellent dielectric properties even at high temperature and low frequency, high reliability even when the dielectric layer is thin, and small capacitance temperature coefficient.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated.

The present invention provides a common material for an internal electrode of a multilayer ceramic capacitor comprising an internal electrode containing a dielectric and a common material.

Same as the dielectric composition; And its composition,

When expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], the values of x, y and m are respectively

 0.55≤x≤0.70

 0.3≤y≤0.4

 0.9960≤m≤1.004

The main component having a range of and Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O _{3 as a secondary} component

(Hereinafter also referred to as "BCG"),

The content of Mn ₃ O ₄ , Al ₂ O ₃ and BCG is made of Mn ₃ O ₄ : 0.5-1.5%, Al ₂ O ₃ : 0.1-0.8% and BCG: 2.0-3.0% with respect to 100 mol of the main component, respectively. It relates to a common material for internal electrodes of a multilayer ceramic capacitor.

In addition, the present invention is a method of manufacturing an internal electrode paste of a multilayer ceramic capacitor comprising an internal electrode containing a dielectric and a common material,

Pre-mixing the Ni powder, the dispersant and the binder, and then dispersing the Ni powder, the dispersing agent to a high viscosity of 100,000 cps or more to prepare a high viscosity metal paste,

Pre-mixing the common material, solvent and dispersant, and then dispersing it to a low viscosity of 1000 cps or less to prepare a low viscosity common material slurry,

Preparing an electrode paste slurry by mixing while dispersing the high-viscosity metal paste and the low-viscosity slurry prepared as described above;

Adjusting the viscosity of the electrode paste slurry prepared as described above and vacuum defoaming, and

Filtering the vacuum degassed electrode paste slurry as described above to produce a final electrode paste; And as a common good

Is the same as the dielectric composition, and the composition is

When expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], the values of x, y and m are respectively

0.55≤x≤0.70

0.3≤y≤0.4

0.9960≤m≤1.004

A main component having a range of Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O ₃ (BCG)

The content of Mn ₃ O ₄ , Al ₂ O ₃ and BCG is made of Mn ₃ O ₄ : 0.5-1.5%, Al ₂ O ₃ : 0.1-0.8% and BCG: 2.0-3.0% with respect to 100 mol of the main component, respectively. The manufacturing method of the internal electrode paste for laminated ceramic capacitors characterized by using a common material.

In addition, the present invention provides a multilayer ceramic capacitor comprising a dielectric sheet and an internal electrode formed by using an internal electrode paste on the dielectric sheet.

The dielectric is used as the dielectric having the same composition as that of the above-described common material of the present invention, and the common material of the present invention is used as the common material of the internal electrode.

In addition, the present invention provides a multilayer ceramic capacitor comprising a dielectric sheet and an internal electrode formed by using an internal electrode paste on the dielectric sheet, wherein the dielectric having the same composition as that of the above-described common material of the present invention is used. The common material of the present invention was used as the electrode material, and the relative dielectric constant was 50 or more, DF was 0.1% or less, IR value was 10 ⁴ MΩ or more, and the capacitance temperature characteristic was U2J characteristic (capacitance change rate) of EIA standard. , ΔC = -750 ± 120ppm / ° C).

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The Ni internal electrode paste of the multilayer ceramic capacitor is usually made of Ni powder, a sintering inhibitor added to delay the shrinkage of the Ni powder, and an organic binder for giving thixotropy and adhesion. Consists of.

Ni powder is produced by liquid phase method and vapor phase method. Ni powder produced by liquid phase method has the advantage of uniform particle size, but poor surface shape, dispersibility is low, and small crystal grain has low oxidation start temperature and low oxidation resistance. There is this.

On the other hand, Ni powder produced by the gas phase method has the advantage of high oxidation resistance, uniform surface, low specific surface area, and excellent dispersibility, while having a large particle size distribution and a high possibility of coarse particles being mixed. Surface roughness may deteriorate and worsen electrode connection.

In general, Ni powder prepared by the gas phase method of 0.4 ~ 0.6㎛ size is mainly used.

However, in recent years, as the MLCC has been required to increase the capacity of internal electrodes, there has been a demand for the development of high quality internal electrode pastes using fine Ni powders having 0.2 to 0.3 µm.

On the other hand, the most important point to consider when designing the internal electrode paste for MLCC is to minimize the internal structural defects such as cracks by reducing the difference in shrinkage between the dielectric with high firing temperature of 1200 ℃ or higher and Ni, the internal electrode. It can be said to reduce clustering or breakage due to underfiring.

Therefore, in order to minimize the sintering start temperature of Ni, which starts sintering at a relatively low temperature of 400 to 500 ° C. as much as possible, ceramic ceramic materials having a composition similar to that of dielectrics are usually added as sintering retardants.

That is, the ceramic material plays a role of delaying the sintering of the internal electrode Ni in the firing process of MLCC, and when the firing of Ni is completed, it exits into the dielectric layer and affects the electrical properties of the dielectric. It should be used as a common material.

In addition, when the particle size of the ceramic material is larger than the Ni powder, the filling rate decreases and the plastic shrinkage rate increases, and since the shrinkage start temperature is lowered because the shrinkage of the Ni powder is not effectively controlled, the size of 0.1 to 0.2 μm is smaller than that of the Ni powder. A ceramic blank is added as a sintering delay material.

Meanwhile, ethyl cellulose is mainly used as a resin of an organic binder for providing thixotropy and adhesiveness, and a solvent has excellent compatibility with resin and a high boiling point. Slow Terpineol system is mainly used.

Screen printing is mainly applied to form the MLCC internal electrode pattern. In the case of the internal electrode paste, it should have appropriate viscosity and thixotropy.

In other words, during printing in which shear rate is large, the viscosity decreases to facilitate printing, but when the squeegee stops at the time of printing, the viscosity increases to maintain the printing shape and improve the resolution. Should have

A binder consisting of ethyl cellulose resin and terpineol solvent is mixed with the Ni powder to impart this thixotropy.

In addition, in order to improve the dispersibility of the Ni powder and the ceramic material, a Ni powder and a dispersant for the material are added, and a petroleum solvent is used as a diluent to adjust the viscosity of the paste suitable for printing.

On the other hand, the manufacturing process of the Ni internal electrode paste generally consists of Ni powder dispersion and common material dispersion, paste mixing and dispersion, viscosity adjustment and defoaming, and filtering.

In the internal electrode paste manufacturing process, how well the dispersion is most important, in particular, the demand for high dispersibility in a high capacity internal electrode paste is very important. Even pastes of the same composition have a large quality difference due to the different dispersibility and uniformity of the Ni powder and the ceramic co-material according to the production method.

That is, when the ceramic material is mixed with the uniformly dispersed Ni powder in a state where the ceramic material is uniformly dispersed without agglomerates, the filling rate of the paste is increased to increase the dry film density, and as a result, the ceramic material effectively delays the shrinkage of the Ni, resulting in sinter shrinkage. The onset temperature is increased, and as a result, the final shrinkage ratio is also reduced.

This minimizes the difference in shrinkage with the dielectric and thus reduces internal structural defects such as cracks caused by internal stress.

On the other hand, in the case of paste having poor dispersibility, Ni powder or common powder generates aggregates, which cause short defects and lower breakdown voltage (BDV). This may cause deterioration of the electrical characteristics.

2 shows a method of manufacturing an internal electrode paste according to a conventional method.

As shown in FIG. 2, conventionally, a 3-roll mill, which is a high viscosity dispersion facility, is used to disperse Ni powder and common materials.

In the case of dispersing Ni powder and common material as described above, Ni can secure dispersibility. However, since the ceramic material has a small particle size and a large specific surface area, the cohesiveness is strong, which leads to difficulty in dispersion. There is a problem of polishing the surface of the roll mill.

Therefore, the internal electrode paste prepared according to the conventional method is poor in dispersibility, aggregates are generated, and roughness of the surface becomes rough, and electrode connectivity is degraded after printing firing, thereby providing a cause of deterioration of chip characteristics.

Therefore, it is important to establish the design and manufacturing process of the internal electrode paste having excellent dispersibility.

The present invention particularly solves the problem of dispersion in the internal electrode paste manufacturing process.

Hereinafter, a method of manufacturing the internal electrode paste will be described with reference to FIG. 3, which shows an example of a method of manufacturing the internal electrode paste according to the present invention.

In order to manufacture the internal electrode paste according to the present invention, as shown in FIG. 3, Ni powder, a dispersant, and a binder are premixed, and then a high viscosity metal paste is prepared by dispersing at a high viscosity of 100,000 cps or more.

As the binder for dispersing Ni, high viscosity ethyl cellulose (Ethyl Cellulose, EC) resin (Resin) is preferably used.

The binder contains a solvent and a resin.

 As an example of binder production, the solvent is first heated to a temperature of 90 ° C., followed by stirring with EC resin while stirring and stirring for 5 hours. A filter (Cartridge filter) can be produced by filtering.

As the solvent, terpineol (Terpineol) system is preferably used.

The Ni powder used in the present invention is not particularly limited to the production method, and any one produced by any of the liquid phase method and the vapor phase method can be used.

It is preferable that the said Ni powder is 0.6 micrometer or less in particle size, More preferably, it is 0.3-0.5 micrometer.

The mixing ratio of the above Ni powder, dispersant and binder is one commonly used.

In the pre-mixing, it is preferable to uniformly wet the binder with Ni powder by sequentially adding a small amount of the binder using a high viscosity planetary mixer (Planetary Mixer, Inoue, Japan).

As described above, a high viscosity metal paste is prepared by dispersing a high viscosity of 100,000 cps or more in a state where the binder is wet with Ni powder, and in this case, it is preferable to use a 3-roll mill.

The principle of the 3-roll mill is that the metal paste is subjected to a strong shear stress as the metal paste passes between the rolls and the gaps between the rolls, so that dispersion is performed. The higher the viscosity, the greater the shear stress. Therefore, when dispersing Ni, it is advantageous to disperse the viscosity at high viscosity of 100,000 cps or more.

When the viscosity of the high-viscosity metal paste is less than 100,000 cps, it is preferable to disperse the metal paste at a high viscosity of 100,000 cps or more because it is difficult to obtain uniform dispersion due to insufficient shearing stress received by the three-roll mill.

In addition, when the premixing is incorrect and the binder is not evenly wetted, the Ni powder mass passes through the narrow gap of the 3-roll mill as it is when producing the high viscosity metal paste, which causes Ni flakes and the like. It reduces the surface roughness of the paste, causing short.

Meanwhile, the common material should be premixed with a solvent and a dispersant, and then dispersed at a low viscosity of 1000 cps or less to prepare a low viscosity slurry.

As the solvent, terpineol (Terpineol) system is preferably used.

The common material is expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], where the values of x, y and m are respectively

0.55≤x≤0.70

0.3≤y≤0.4

0.9960≤m≤1.004

The main component having a range of and Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O _{3 as a secondary} component

(BCG),

The content of Mn ₃ O ₄ , Al ₂ O ₃ and BCG is composed of Mn ₃ O ₄ : 0.5-1.5%, Al ₂ O ₃ : 0.1-0.8% and BCG: 2.0-3.0% with respect to 100 mol of the main component, respectively. .

It is preferable to set the particle size of the common material formed as mentioned above to 0.4 micrometer or less, More preferably, you may be 0.2 micrometer or less.

Since the common material is ceramic and has a high hardness and fine powder, it has a high cohesiveness. Therefore, the common material is preferably dispersed at a low viscosity of 1000 cps or less using a beads mill while applying strong impact and stress.

When the viscosity of the low viscosity reciprocating slurry is greater than 1000 cps, it is difficult to ensure uniform dispersion due to coagulation at the time of dispersion. Therefore, the viscosity of the low viscosity reciprocating slurry is preferably set to 1000 cps or less. .

As an example of the method for preparing the common slurry, first, a solvent and a dispersant are added to a tank, and premixed with an impeller, followed by one step for at least 6 hours, preferably 6 to 12 hours, in a beads mill. The method of stabilizing a slurry by carrying out dispersion | dispersion, after completion | finish of 1st stage dispersion | distribution, and adding a common binder for 2 hours or more, preferably 3 to 6 hours, is carried out.

In preparing the low viscosity co-processing slurry, a resin having a low molecular weight and a low viscosity may be added.

The electrode paste slurry is prepared by mixing while dispersing the high viscosity metal paste and the low viscosity co-processing slurry prepared as described above.

That is, it is preferable to prepare the electrode paste slurry by mixing the high-viscosity metal paste and the low-viscosity slurry in a planetary mixer and then uniformly mixing and dispersing in a three-roll mill.

After preparing the electrode paste slurry prepared as described above, a viscosity adjustment process for diluting to a viscosity suitable for printing is performed, in which vacuum degassing is carried out to remove micro bubbles trapped therein.

As an example, the electrode paste slurry is further viscosity-adjusted to 18000 ± 3000 cps using a solvent and a diluent in a planetary mixer, and a method of defoaming in vacuum is performed.

Finally, the final electrode paste is prepared by using a filter to filter out remaining aggregates.

An example of the filter is 500 mesh or more, and preferably 500-2000 mesh filter.

Hereinafter, a multilayer ceramic capacitor to which the internal electrode paste manufactured as described above is applied will be described.

In the multilayer ceramic capacitor, as shown in FIG. 1, the internal electrode 2 is formed on the dielectric layer sheet 1 using an internal electrode paste by a printing method or the like, and a plurality of dielectric layers on which the internal electrodes are printed are laminated. The internal electrode of the body weight and the dielectric layer are fired at the same time, and then connected to the internal electrode to form an external electrode 3 for exerting capacitance, and the plating layers 4 and 5 are formed to prevent problems during soldering. It is manufactured by.

The multilayer ceramic capacitor of the present invention uses the internal electrode paste of the present invention as the above internal electrode paste.

That is, the multilayer ceramic capacitor of the present invention uses one having the same composition as the dielectric material as one of the components constituting the internal electrode paste.

As described above, by making the composition of the common material contained in the internal electrode the same as that of the dielectric, the multilayer ceramic capacitor is excellent in dielectric properties even at high temperature and low frequency, has high reliability even when the dielectric layer is thin, and has a small capacitance temperature coefficient. Will have

The multilayer ceramic capacitor of the present invention preferably has a relative dielectric constant of 50 or more, DF of 0.1% or less, an IR value of 10 ⁴ MΩ or more, and a capacitance temperature characteristic of the U2J characteristic (capacitance change rate, ΔC = -750 ±) of the EIA standard. 120 ppm / ° C).

Hereinafter, the present invention will be described in more detail with reference to Examples.

(Example)

In this embodiment, a multilayer ceramic capacitor was manufactured according to the process sequence of FIG. 4 which shows a manufacturing process of a conventional multilayer ceramic capacitor.

As starting materials, CaCO ₃ , SrCO ₃ , TiO ₂ and ZrO ₂ were weighed and combined so as to produce a main component having a composition range as shown in Table 1 below, and then heat-treated at 1250˜1270 ° C. to [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ] was prepared, and the average particle diameter was 0.65 ± 0.15 μm.

BCG was weighed and combined with Mn ₃ O ₄ , Al ₂ O _3, and a sintering aid as shown in Table 1 below.

In this case, UJ-2 of Table 1 was used as a material for internal electrodes.

As the BCG, BaCO ₃ , CaCO ₃ and SiO ₂ powders were calcined and calcined in advance, and calcination of the BCG was performed at least 1000 ° C. for 2 hours.

The above-mentioned BCG (sintering aid) used what was grind | pulverized so that the average particle diameter might be 1.0 micrometer or less.

The powder weighed as described above was wet mixed and pulverized and then dehydrated and dried.

A binder and a solvent were added to the dried powder as described above, an organic binder was added in an appropriate amount, mixed, and a slurry was prepared.

As the binder, a polyvinyl butyl binder was used.

The slurry was used to apply a film about 20 to 30 탆 thick by a doctor blade method to form a dielectric ceramic composition sheet.

Ni paste as an internal electrode material was printed on the dielectric ceramic composition sheet molded as described above.

The Ni paste was prepared as follows.

As shown in FIG. 3, Ni powder, a dispersant, and a binder having a particle size of 0.4 μm were premixed using a Pranetary mixer, and then dispersed to a high viscosity of 100,000 cps or more using a 3-roll mill to prepare a high viscosity metal paste. As a binder for dispersing Ni, high viscosity ethyl cellulose (Ethyl Cellulose, EC) resin (Resin) and terpineol (Terpineol) solvents were used.

On the other hand, using a premixer (premixer) was premixed together with the raw material, solvent and dispersant having a particle size of 0.2㎛, and then dispersed to a low viscosity of less than 1000cps beads mill (beads mill) to produce a low viscosity slurry slurry. UJ-2 was used, and terpineol was used as a solvent.

The electrode paste slurry was prepared by mixing the high-viscosity metal paste and the low-viscosity slurry as described above in a prenary mixer, and then uniformly mixing and dispersing in a three-roll mill.

The electrode paste slurry prepared as described above was viscosity-adjusted to 18000 ± 3000 cps using a solvent and diluent in a planetary mixer, degassed in vacuum, and then remained using a # 2000 mesh filter. The resulting aggregates were filtered to prepare a final internal electrode paste.

Next, the dielectric ceramic composition printed as described above was laminated for each model, and a protective dummy sheet without printing internal electrodes was stacked on both upper and lower surfaces, and pressed to 500 to 1200 kgf / cm 2 to form a laminate.

The laminated body compressed as described above was cut into a predetermined capacitor size according to the internal electrode pattern.

  The laminate cut as described above was subjected to primary calcining in air at 250 ° C. for 43 hours and then calcined at 850 ° C. for 4 hours in nitrogen atmosphere.

Firing was carried out at 1290 to 1310 ° C. for 2 hours in a reducing atmosphere of P _{O 2} = ˜10 ⁻¹¹ atm.

After that, the fired body was polished, and a Cu conductive paste made of Cu, glass frit, and vehicle was applied to the side of the fired body where the end of the internal electrode was exposed, dried, and then heat-treated at 700-800 ° C. for the laminated ceramic. A capacitor was prepared. Finally, Ni, Sn-Pb plating layers were formed on the external electrodes by electroplating.

For the multilayer ceramic capacitor manufactured as described above, electrical characteristics such as relative dielectric constant (εr), dielectric loss (tanδ), specific resistance (Ωm), and temperature characteristic of capacitance (TCC (ppm)) were measured, and as a result, Is shown in Table 2 below.

Here, the relative dielectric constant (εr) and the dielectric loss (tanδ) are measured at a frequency of 1 MHz at room temperature (25 ° C.), and the specific resistance (m · m) is measured at IR at 250 V at room temperature for 60 seconds after current application. It is converted into.

The capacitance temperature characteristic (TCC) is represented by TCC (ppm / ° C.) = {(C125-C25) / C25} × {1 / (125-25)} × 10 ⁶ .

Sample Number Main component [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ] Subcomponents (mol% of 100 mol of main component) x 1-x y 1-y m Mn ₃ O ₄ Al ₂ O ₃ BCG UJ-1 0.5894 0.4106 0.3189 0.6811 1.0000 1.00% 0.20% 2.80% UJ-2 0.6894 0.3106 0.3189 0.6811 1.0000 1.00% 0.20% 2.80% UJ-3 0.7894 0.2106 0.3189 0.6811 1.0000 1.00% 0.20% 2.80% UJ-4 0.8894 0.1106 0.3189 0.6811 1.0000 1.00% 0.20% 2.80% UJ-5 0.9894 0.0106 0.3189 0.6811 1.0000 1.00% 0.20% 2.80% UJ-6 0.6894 0.3106 0.1900 0.8100 1.0000 1.00% 0.20% 2.80%

Sample Number Permittivity (ε) DF (%) Resistivity ρ TCC (-55 ° C) TCC (125 ℃) BDV (KV) Accelerated Life (Fit) UJ-1 71 0.049 3.25E + 14 -804 -655 1.36 0.08 UJ-2 69 0.028 3.30E + 14 -859 -678 1.74 0.07 UJ-3 67 0.034 4.72E + 14 -755 -587 1.21 1.02 UJ-4 65 0.022 2.35E + 15 -781 -593 0.91 2.44 UJ-5 64 0.023 5.18E + 15 -824 -617 1.12 8.14 UJ-6 50 0.028 5.44E + 15 -428 -333 1.34 2.15

As shown in Table 1 and Table 2, according to the present invention, a dielectric constant of 50 or more, DF of 0.1% or less, and an IR value are obtained by applying the reducing-resistant dielectric composition and the dielectric composition as a common material for the conductive Ni nonmetal internal electrode paste. It exhibits 10 ⁴ MΩ or more, there is no deterioration of insulation resistance (IR) due to firing, and the capacitance temperature characteristic satisfies the U2J characteristic (capacitance change rate, ΔC = -750 ± 120ppm / ° C) of the EIA standard, and also the insulation resistance It can be seen that a multilayer ceramic capacitor having a long lifetime can be manufactured.

Since the internal electrode paste material of the present invention has a reducing resistance composition, it can be used as an internal electrode of a multilayer ceramic capacitor having U2J characteristics (capacitance change rate, ΔC = -750 ± 120ppm / ° C).

As described above, according to the present invention, the dielectric constant is 50 or more, DF is 0.1% or less, the IR value is 10 ⁴ MPa or more, there is no degradation of the insulation resistance (IR) due to firing, and the capacity temperature characteristic is that of the EIA standard. A multilayer ceramic capacitor can be provided that satisfies U2J characteristics (capacitance change rate, ΔC = -750 ± 120ppm / ° C).

1 is a schematic view showing an example of a conventional multilayer ceramic capacitor

2 is a process chart showing a process of manufacturing an internal electrode paste for a multilayer ceramic capacitor according to a conventional method.

3 is a process chart showing an example of a process of manufacturing an internal electrode paste for a multilayer ceramic capacitor according to the present invention.

4 is a process chart showing a process of manufacturing a multilayer ceramic capacitor according to a conventional method.

Explanation of symbols on main parts of drawing

One . . . Dielectric sheet 2. . . Internal electrode 3. . . External electrode

Claims (7)

In a multilayer ceramic capacitor comprising an internal electrode containing a dielectric and a common material, Same as the dielectric composition; And its composition, When expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], the values of x, y and m are respectively   0.55≤x≤0.70   0.3≤y≤0.4   0.9960≤m≤1.004 A main component having a range of Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O ₃ (BCG) The content of Mn ₃ O ₄ , Al ₂ O ₃ and BCG is made of Mn ₃ O ₄ : 0.5-1.5%, Al ₂ O ₃ : 0.1-0.8% and BCG: 2.0-3.0% with respect to 100 mol of the main component, respectively. A common material for internal electrodes of multilayer ceramic capacitors, characterized in that In the method of manufacturing an internal electrode paste of a multilayer ceramic capacitor comprising an internal electrode containing a dielectric and a common material, Premixing Ni powder, dispersant and binder using a planetary mixer, and then dispersing Ni powder, dispersant and binder to a high viscosity of 100,000 cps or more using a 3-roll mill to prepare a high viscosity metal paste , Pre-mixing the common material, solvent, and dispersant, and then dispersing it to a low viscosity of 1000 cps or less using a bead mill to produce a low viscosity common material slurry The high viscosity metal paste and the low viscosity common material slurry prepared as described above Preparing an electrode paste slurry by mixing while dispersing using a 3-roll mill, Adjusting the viscosity of the electrode paste slurry prepared as described above and vacuum defoaming, and Filtering the vacuum degassed electrode paste slurry as described above to produce a final electrode paste; And as a common good Is the same as the dielectric composition, and the composition is When expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], the values of x, y and m are respectively   0.55≤x≤0.70   0.3≤y≤0.4   0.9960≤m≤1.004 A main component having a range of Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O ₃ (BCG) The content of Mn ₃ O ₄ , Al ₂ O ₃ and BCG is made of Mn ₃ O ₄ : 0.5-1.5%, Al ₂ O ₃ : 0.1-0.8% and BCG: 2.0-3.0% with respect to 100 mol of the main component, respectively. Method for manufacturing internal electrode paste for multilayer ceramic capacitors, characterized in that a common material is used The method of manufacturing an internal electrode paste for a multilayer ceramic capacitor according to claim 2, wherein the Ni powder has a particle size of 0.3 to 0.5 mu m. The method of manufacturing an internal electrode paste for a multilayer ceramic capacitor according to claim 2, wherein the particle size of the common material is 0.2 µm or less. The binder according to any one of claims 2 to 4, wherein the binder comprises a resin and a solvent, The resin is ethyl cellulose (Ethyl Cellulose) resin, and the solvent is terpineol (Terpineol) manufacturing method of the internal electrode paste for a multilayer ceramic capacitor A multilayer ceramic capacitor comprising a dielectric sheet and an internal electrode formed by using an internal electrode paste containing a common material in the dielectric sheet, The common material has the same composition as the dielectric, and the composition of the common material is When expressed as [(Ca _x Sr _1-x ) O] _m [(Ti _y Zr _1-y ) O ₂ ], the values of x, y and m are respectively   0.55≤x≤0.70   0.3≤y≤0.4   0.9960≤m≤1.004 A main component having a range of Mn ₃ O ₄ and Al ₂ O ₃ and Ba _0.53 Ca _0.19 Si _0.28 O ₃ (BCG) The content of Mn ₃ O ₄ , Al ₂ O ₃ and BCG is made of Mn ₃ O ₄ : 0.5-1.5%, Al ₂ O ₃ : 0.1-0.8% and BCG: 2.0-3.0% with respect to 100 mol of the main component, respectively. Multilayer ceramic capacitor The capacitor has a dielectric constant of 50 or more, a DF of 0.1% or less, an IR value of 10 ⁴ MΩ or more, and a capacitance temperature characteristic of the U2J characteristic of the EIA standard (capacitance change rate, ΔC = −750 ± 120 ppm). / ℃) multilayer ceramic capacitors characterized in that