CN113725003A - Multilayer ceramic capacitor terminal electrode structure and preparation method thereof - Google Patents
Multilayer ceramic capacitor terminal electrode structure and preparation method thereof Download PDFInfo
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/002—Details
- H01G4/228—Terminals
- H01G4/232—Terminals electrically connecting two or more layers of a stacked or rolled capacitor
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G13/00—Apparatus specially adapted for manufacturing capacitors; Processes specially adapted for manufacturing capacitors not provided for in groups H01G4/00 - H01G11/00
- H01G13/006—Apparatus or processes for applying terminals
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/002—Details
- H01G4/018—Dielectrics
- H01G4/06—Solid dielectrics
- H01G4/08—Inorganic dielectrics
- H01G4/12—Ceramic dielectrics
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/002—Details
- H01G4/228—Terminals
- H01G4/232—Terminals electrically connecting two or more layers of a stacked or rolled capacitor
- H01G4/2325—Terminals electrically connecting two or more layers of a stacked or rolled capacitor characterised by the material of the terminals
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/30—Stacked capacitors
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- Engineering & Computer Science (AREA)
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- Manufacturing & Machinery (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Inorganic Chemistry (AREA)
- Ceramic Capacitors (AREA)
- Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
Abstract
The invention discloses a multilayer ceramic capacitor terminal electrode structure and a preparation method thereof, belonging to the field of electronic elements. Compared with the traditional multilayer ceramic capacitor terminal electrode, the multilayer ceramic capacitor terminal electrode structure adopts the organic layer to replace the common tin layer, so that the good welding performance of the multilayer ceramic capacitor can be effectively maintained, the tin plating step in the preparation process can be omitted, the investment of electroplating equipment, raw materials, energy consumption and the like is reduced, the production cost is obviously reduced, the environmental protection performance of the product can be improved, the production period of the product is shortened by 110-170 min, and the productivity is improved; after the product is welded on a circuit board by reflow soldering, the circuit board vibration noise caused by the piezoelectric effect of the multilayer ceramic capacitor can be inhibited, and meanwhile, the product cannot fall off from the circuit board. The invention also discloses a preparation method of the multilayer ceramic capacitor terminal electrode structure, which has the advantages of simple operation steps, low production cost and short time consumption, and can realize industrial large-scale production.
Description
Technical Field
The invention relates to the field of electronic elements, in particular to a multilayer ceramic capacitor terminal electrode structure and a preparation method thereof.
Background
The terminal electrode of the multilayer ceramic capacitor is generally a covered copper (or nickel, silver, palladium, copper-nickel alloy, silver-palladium alloy and the like), nickel and tin three-layer metal structure from inside to outside in sequence. Wherein, the innermost copper layer is directly connected with the inner electrode of the capacitor and is a base material of the terminal electrode; the middle nickel layer is a soldering tin barrier layer which can prevent the soldering tin from corroding the copper layer when the capacitor is welded; the outermost tin layer is the terminal electrode surface layer directly contacted with the soldering tin and is a bridge for connecting the multilayer ceramic capacitor and the circuit board. Typically, the innermost copper layer is formed by coating and sintering a copper paste, and the intermediate nickel layer and the outermost tin layer are formed by electroplating. The tin layer is used as the end electrode surface layer and has the advantages of low melting point (232 ℃), easy welding, corrosion resistance, discoloration resistance, good ductility, excellent conductivity and the like.
However, the tin plating process has the following disadvantages: (1) the time is long (generally 1 hour to 3 hours), and the production efficiency is low; (2) the sewage generated in the tinning process is more, which is not beneficial to environmental protection; (3) the consumption of tin metal, electric energy and clean water is extremely large.
In addition, the multilayer ceramic capacitor using the high dielectric constant ceramic material as a dielectric has a piezoelectric effect, and when the multilayer ceramic capacitor is mounted on a circuit board and an alternating voltage is applied, the capacitor generates vibration and transmits the vibration to the circuit board through a terminal electrode and solder, so that the circuit board vibrates and generates noise. The vibration and noise become more intense as the capacitance of the multilayer ceramic capacitor increases.
Disclosure of Invention
Based on the defects in the prior art, the invention aims to provide a multilayer ceramic capacitor terminal electrode structure which has good welding performance without an outermost tin layer, so that various problems caused by a tin plating step in a conventional terminal electrode preparation process are avoided.
In order to achieve the purpose, the invention adopts the technical scheme that:
a multilayer ceramic capacitor terminal electrode structure comprises a first metal layer, a second metal layer and an organic layer which are sequentially covered from inside to outside; the first metal layer is attached to two ends of the ceramic body of the multilayer ceramic capacitor; the organic layer is a polymeric organic film.
Compared with the traditional multilayer ceramic capacitor terminal electrode, the multilayer ceramic capacitor terminal electrode structure provided by the invention has the advantages that the organic layer is adopted to replace a common tin layer, so that the good welding performance of the multilayer ceramic capacitor can be effectively maintained, a tin plating step in the preparation process can be omitted, the investment of electroplating equipment, raw materials, energy consumption and the like is reduced, the production cost is obviously reduced, the environmental friendliness of the product can be improved, the production period of the product is shortened by 110-170 min, and the productivity is improved. Moreover, after the multilayer ceramic capacitor is welded on the circuit board by reflow soldering, compared with the prior art, the climbing height of the solder is properly reduced, the circuit board vibration noise caused by the piezoelectric effect of the multilayer ceramic capacitor can be inhibited, and the multilayer ceramic capacitor is ensured not to fall off from the circuit board.
Preferably, the preparation raw material of the organic layer is an organic solution, and the organic solution consists of the following components in percentage by mass: 10.5-20% of high molecular polymer, 79-89% of benzene organic solvent and 0.5-1% of stabilizer.
At the content, the high molecular polymer can obtain an organic layer with uniform thickness and high coverage rate, and if the content is too low, the organic layer is not uniform in thickness and cannot sufficiently cover the second metal layer; on the other hand, if the content is too high, the solute is likely to precipitate from the organic solution, and the formation of a uniform organic layer is also not facilitated.
The benzene organic solvent with the content is beneficial to improving the solubility of the organic solvent, so that the uniformity of the organic solution is good, and if the content is too low, a solute is easy to separate out of the organic solution; and if the content is too high, it is difficult to obtain an organic layer having a uniform thickness and a high coverage.
The stabilizing agent is favorable for preventing the precipitation of the solute and maintaining the stability of the solution at normal temperature under the content, and if the content is too low, the solute is easy to precipitate from the organic solution; and if the content is too high, it is not favorable for forming a uniform organic layer.
More preferably, the high molecular polymer comprises at least one of polyimide and parylene;
more preferably, the benzene-based organic solvent comprises at least one of toluene and xylene;
more preferably, the stabilizer comprises at least one of a carboxylate, a lactate.
The preferable high polymer can be melted at 120-160 ℃, so that the multilayer ceramic capacitor can effectively play a role in wetting a metal layer in the welding process, the surface tension of the terminal electrode is reduced, the terminal electrode is fused with the terminal electrode of the multilayer ceramic capacitor into a whole when soldering tin is melted, and finally the multilayer ceramic capacitor is firmly welded on a circuit board; meanwhile, the prepared organic film layer is compact and has no gap, and the oxidation of the metal layer covered inside can be effectively prevented. The preferable benzene organic solvent has higher solubility to general high molecular polymers, can effectively prevent the precipitation of solute by matching with a stabilizer, and ensures that the organic solution prepared from the specific components in the proportion has normal temperature stability.
Preferably, the preparation method of the organic layer is as follows: and cleaning the multilayer ceramic capacitor covered with the second metal layer, soaking the multilayer ceramic capacitor into an organic solution, and then sequentially airing and baking to finish the preparation of the organic layer.
In the conventional preparation of the terminal electrode of the multilayer ceramic capacitor, a device covered with a nickel layer metal layer is generally soaked in a solder electroplating solution prepared by organic reagents such as sulfonic acid alkanol and the like, and then a solder coating is formed on the nickel layer metal layer through an electrochemical reaction. The organic solution does not contain metal elements, has hydrophilicity and small surface tension with the metal layer, so that the organic solution can be directly coated in a physical soaking adhesion mode, and the organic layer adhered to the second metal layer has strong adhesion.
More preferably, the temperature during soaking is 60-90 ℃ and the time is 3-5 min, and the multilayer ceramic capacitor is continuously stirred in the soaking process.
At the soaking temperature, the organic solution can reach a relatively saturated state, which is favorable for soaking to form a film, and if the temperature is too high, the solvent volatilizes fast, so that the stable concentration is difficult to maintain; and under the preferable soaking time, the multilayer ceramic capacitor in the soaking process is continuously stirred, so that the organic solution can fully soak the surface of the second metal layer.
More preferably, the baking temperature is 90-100 ℃ and the baking time is 0.8-1.2 h.
Under the condition, the solvent remained on the surface of the device can be completely volatilized, and the organic solution can be effectively solidified into the organic layer covered on the second metal layer.
Preferably, the first metal layer includes any one of a copper layer, a nickel layer, a silver layer, a palladium layer, a copper-nickel alloy layer, and a silver-palladium alloy layer.
Preferably, the thickness of the first metal layer is 15-80 μm.
The first metal layer can be ensured to have good covering and bonding force on the ceramic body of the multilayer ceramic capacitor under the thickness, and if the thickness is too thin, the first metal layer is not beneficial to fully covering the ceramic body and is easy to fall off; on the other hand, if the thickness is too large, the multilayer ceramic capacitor is not compact.
Preferably, the second metal layer is a nickel layer.
Preferably, the thickness of the second metal layer is 2-5 μm.
The loss of the first metal layer can be prevented during the welding of the multilayer ceramic capacitor under the thickness, and if the thickness is too thin, the protection of the first metal layer is not facilitated; if the thickness is too thick, it is not favorable for miniaturization and reducing the stress of the second metal layer.
Preferably, the thickness of the organic layer is 0.1 to 0.5 μm.
The good welding performance of the multilayer ceramic capacitor can be ensured under the thickness, if the thickness is too thin, the organic layer is difficult to fully cover the second metal layer, and the wetting effect in the process of welding the multilayer ceramic capacitor is insufficient; if the thickness is too thick, the time required for melting the organic layer is too long when the multilayer ceramic capacitor is welded, and the wetting effect cannot be exerted in time.
The invention also aims to provide a preparation method of the multilayer ceramic capacitor terminal electrode structure, which comprises the following steps:
(1) coating metal slurry on two ends of a ceramic body of the multilayer ceramic capacitor and heating and sintering the metal slurry to form first metal layers attached to the two ends of the ceramic body;
(2) preparing a second metal layer covering the outer surface of the first metal layer formed in the step (1) by an electroplating method;
(3) and cleaning the multilayer ceramic capacitor covered with the second metal layer, soaking the multilayer ceramic capacitor in an organic solution, and then sequentially airing and baking to obtain an organic layer covered on the surface of the second metal layer, thus obtaining the terminal electrode structure of the multilayer ceramic capacitor.
The preparation method of the multilayer ceramic capacitor terminal electrode structure has the advantages of simple operation steps, low requirements on production equipment, low industrial cost and short production process time, and can realize industrial large-scale production.
Preferably, the metal slurry in the step (1) is copper slurry, the coating method comprises any one of dipping and spraying, and the heating and sintering temperature is 700-900 ℃ and the time is 5-15 min.
Preferably, the electroplating method in the step (2) comprises any one of a vibrating screen electroplating method, a rolling screen electroplating method and a centrifugal electroplating method, wherein the current used in the electroplating method is 40-100A, and the electroplating time is 60-120 min.
And under the parameters, the second metal layer with the thickness of 2-5 mu m can be prepared according to the actual condition by an electroplating method.
The multilayer ceramic capacitor terminal electrode structure has the beneficial effects that compared with the traditional multilayer ceramic capacitor terminal electrode, the organic layer is adopted to replace a common tin layer, so that the good welding performance of the multilayer ceramic capacitor can be effectively maintained, a tinning step in the preparation process can be omitted, the investment of electroplating equipment, raw materials, energy consumption and the like is reduced, the production cost is obviously reduced, the environmental protection performance of the product can be improved, the production period of the product is shortened by 110-170 min, and the productivity is improved; after the multilayer ceramic capacitor is welded on a circuit board by reflow soldering, the vibration noise of the circuit board caused by the piezoelectric effect of the multilayer ceramic capacitor can be inhibited, and meanwhile, the multilayer ceramic capacitor is ensured not to fall off from the circuit board. The invention also provides a preparation method of the multilayer ceramic capacitor terminal electrode structure, which has the advantages of simple operation steps, low requirement on production equipment, low industrialized cost, short production process and capability of realizing industrialized mass production.
Drawings
FIG. 1 is a schematic cross-sectional view of a conventional multilayer ceramic capacitor terminal electrode structure of the prior art;
FIG. 2 is a schematic cross-sectional view of the terminal electrode structure of the multilayer ceramic capacitor according to the present invention;
FIG. 3 is a schematic sectional view of the multilayer ceramic capacitor terminal electrode obtained in example 1;
FIG. 4 is a schematic sectional view of the terminal electrode of the multilayer ceramic capacitor obtained in comparative example 1;
FIG. 5 is a sectional view showing a multilayer ceramic capacitor solder-mounted on a circuit board in example 1;
FIG. 6 is a schematic sectional view of a multilayer ceramic capacitor solder-mounted on a circuit board in comparative example 1.
Detailed Description
In order to better illustrate the objects, technical solutions and advantages of the present invention, the present invention will be further described with reference to specific examples and comparative examples, which are intended to be understood in detail, but not intended to limit the invention. All other embodiments obtained by a person skilled in the art without making any inventive step are within the scope of protection of the present invention. The experimental reagents and instruments designed for the practice of the present invention and the comparative examples are common reagents and instruments unless otherwise specified.
Example 1
The embodiment of the end electrode structure of the multilayer ceramic capacitor comprises a first metal layer, a second metal layer and an organic layer which are sequentially covered from inside to outside; the first metal layer is attached to two ends of the ceramic body of the multilayer ceramic capacitor; the organic layer is a polymer organic film; the structural section of the product is shown in FIG. 2; the preparation method of the product comprises the following steps:
(1) coating copper slurry on two ends of a ceramic body of the multilayer ceramic capacitor, heating the ceramic body to 800 ℃ in nitrogen, sintering and preserving heat for 10min to ensure that the slurry forms two copper layers (first metal layers) attached to the two ends of the ceramic body; the thickness of the single copper layer is 30 μm;
(2) preparing a second metal layer with the thickness of 4 microns, which covers the outer surface of the first metal layer formed in the step (1), by a vibrating screen electroplating method; the second metal layer is a nickel layer; the current used by the electroplating method is 60A, and the electroplating time is 80 min;
(3) cleaning the multilayer ceramic capacitor covered with the second metal layer for 2-3 times by using deionized water, wherein the time is 3-5 min each time to remove redundant residual electroplating solution, screening the multilayer ceramic capacitor and electroplating media, cleaning the multilayer ceramic capacitor, immediately placing the multilayer ceramic capacitor into an organic solution to prevent a nickel layer from being significantly oxidized, soaking the multilayer ceramic capacitor at 80 ℃ for 4min, taking out and drying the multilayer ceramic capacitor, placing the multilayer ceramic capacitor in a baking oven for baking at 95 ℃ for 1h to obtain an organic layer with the thickness of 0.2 mu m covering the surface of the second metal layer, and obtaining the terminal electrode structure of the multilayer ceramic capacitor; the organic solution comprises the following components in percentage by mass: 15.2 percent of high molecular polymer, 84 percent of benzene organic solvent and 0.8 percent of stabilizer.
The high molecular polymer is polyimide; the benzene organic solvent is toluene; the stabilizer is sodium carboxylate.
The cross section schematic diagram of the conventionally prepared multilayer ceramic capacitor terminal electrode structure is shown in figure 1, and copper layers, nickel layers and tin layers are covered from inside to outside as metal layers, while the multilayer ceramic capacitor terminal electrode structure (figure 2) adopts an organic layer to replace a common tin layer, so that the good welding performance of the multilayer ceramic capacitor can be effectively maintained, a tinning step in the preparation process can be omitted, the investment of electroplating equipment, raw materials, energy consumption and the like can be reduced, the production cost can be obviously reduced, the environmental protection performance of the product can be improved, the production period of the product can be shortened by 110-170 min, and the productivity can be improved.
In order to verify the optimization of each formula and preparation parameters of the organic layer in the terminal electrode structure of the multilayer ceramic capacitor, in the preparation process of the organic layer of the product of the embodiment, the proportions of different high molecular polymers, benzene organic solvents and stabilizers, and the soaking time and temperature in the step (3) are adjusted, wherein the adjustment parameters are shown in table 1, and the welding test is performed on the products prepared by the different parameters. In the soldering test, the multilayer ceramic capacitor is immersed in 275 ℃ molten solder and kept for 5 seconds, and then taken out, and the terminal electrode is observed under a solid microscope, wherein the solder coverage rate is the area of the terminal electrode covered with solder divided by the total area of the terminal electrode multiplied by 100%, the solder coverage rate is more than or equal to 95%, and the terminal electrode is judged to be qualified, and the solder coverage rate is less than 95%, and the terminal electrode is judged to be unqualified.
TABLE 1
As can be seen from Table 1, the end electrode structure of the multilayer ceramic capacitor manufactured by using the organic solvent with non-preferred composition or manufacturing parameters can not achieve the qualified welding coverage rate, and even the risk of solute precipitation can occur during the formation of the organic layer.
Comparative example 1
The comparative example differs from example 1 only in that the organic layer in the terminal electrode structure of the multilayer ceramic capacitor described in the comparative example is replaced with a tin layer.
The products of example 1 and comparative example 1 were cut into pieces and observed for cross-section, and the results are shown in fig. 3 and 4, respectively. The multilayer ceramic capacitor terminal electrode obtained in comparative example 1 was a visible three-layer metal structure, with the outermost layer being a tin layer; the multilayer ceramic capacitor terminal electrode obtained in example 1 had only a two-layer metal structure and no tin layer, but the outermost organic layer originally was hardly distinguishable by naked eyes because it was fused with a resin for fixing the multilayer ceramic capacitor.
The multilayer ceramic capacitors of example 1 and comparative example 1 were mounted on circuit boards using reflow soldering, respectively, and then the circuit boards mounted with the multilayer ceramic capacitors were cut into pieces and the cross-sections were observed, and the results are shown in fig. 5 and 6, respectively. In the product obtained in comparative example 1, the rising height of the solder reached the top surface of the multilayer ceramic capacitor facing away from the circuit board, and although the multilayer ceramic capacitor was more firmly bonded to the circuit board, the piezoelectric vibration generated from the multilayer ceramic capacitor was largely transmitted to the circuit board through the contact surface with the solder, thereby generating a large noise. In the product obtained in example 1, the tin layer is replaced by the organic layer, so that the climbing height of the solder is properly reduced and reaches about 2/3 of the multilayer ceramic capacitor, thereby ensuring firm combination of the multilayer ceramic capacitor and the circuit board, reducing the transmission of piezoelectric vibration and remarkably inhibiting the vibration noise of the circuit board.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (10)
1. A multilayer ceramic capacitor terminal electrode structure is characterized by comprising a first metal layer, a second metal layer and an organic layer which are sequentially covered from inside to outside; the first metal layer is attached to two ends of the ceramic body of the multilayer ceramic capacitor; the organic layer is a polymeric organic film.
2. The multilayer ceramic capacitor terminal electrode structure of claim 1, wherein the organic layer is prepared from an organic solution comprising the following components in percentage by mass: 10.5-20% of high molecular polymer, 79-89% of benzene organic solvent and 0.5-1% of stabilizer; the thickness of the organic layer is 0.1-0.5 μm.
3. The multilayer ceramic capacitor end electrode structure of claim 2, wherein said high molecular polymer comprises at least one of polyimide, parylene; the benzene organic solvent comprises at least one of toluene and xylene; the stabilizer comprises at least one of carboxylate and lactate.
4. The multilayer ceramic capacitor terminal electrode structure of claim 2, wherein the organic layer is prepared by a method comprising: and cleaning the multilayer ceramic capacitor covered with the second metal layer, soaking the multilayer ceramic capacitor into an organic solution, and then sequentially airing and baking to finish the preparation of the organic layer.
5. The terminal electrode structure of a multilayer ceramic capacitor according to claim 4, wherein the temperature during the soaking is 60 to 90 ℃ for 3 to 5min, and the multilayer ceramic capacitor is continuously stirred during the soaking.
6. The multilayer ceramic capacitor terminal electrode structure of claim 4, wherein said baking is carried out at a temperature of 90 to 100 ℃ for 0.8 to 1.2 hours.
7. The multilayer ceramic capacitor terminal electrode structure of claim 1, wherein said first metal layer comprises any one of a copper layer, a nickel layer, a silver layer, a palladium layer, a copper-nickel alloy layer, a silver-palladium alloy layer; the thickness of the first metal layer is 15-80 μm.
8. The multilayer ceramic capacitor end electrode structure of claim 1, wherein said second metal layer is a nickel layer; the thickness of the second metal layer is 2-5 μm.
9. The method for producing a multilayer ceramic capacitor terminal electrode structure according to any one of claims 1 to 8, comprising the steps of:
(1) coating metal slurry on two ends of a ceramic body of the multilayer ceramic capacitor and heating and sintering the metal slurry to form first metal layers attached to the two ends of the ceramic body;
(2) preparing a second metal layer covering the outer surface of the first metal layer formed in the step (1) by an electroplating method;
(3) and cleaning the multilayer ceramic capacitor covered with the second metal layer, soaking the multilayer ceramic capacitor in an organic solution, and then sequentially airing and baking to obtain an organic layer covered on the surface of the second metal layer, thus obtaining the terminal electrode structure of the multilayer ceramic capacitor.
10. The method for producing a multilayer ceramic capacitor terminal electrode structure according to claim 9, comprising at least one of the following technical features (a) and (b):
(a) the metal slurry in the step (1) is copper slurry, the coating method comprises any one of dipping and spraying, the heating and sintering temperature is 700-900 ℃, and the time is 5-15 min;
(b) the electroplating method in the step (2) comprises any one of a vibrating screen electroplating method, a rolling screen electroplating method and a centrifugal electroplating method, wherein the current used in the electroplating method is 40-100A, and the electroplating time is 60-120 min.
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CN1574129A (en) * | 2003-05-27 | 2005-02-02 | 株式会社村田制作所 | Multilayer ceramic electronic component and mounting structure and method for the same |
JP2014187058A (en) * | 2013-01-14 | 2014-10-02 | Samsung Electro-Mechanics Co Ltd | Multilayer ceramic capacitor, mounting board for multilayer ceramic capacitor, and manufacturing method of multilayer ceramic capacitor |
US20170032896A1 (en) * | 2015-07-30 | 2017-02-02 | Murata Manufacturing Co., Ltd. | Multilayer ceramic capacitor and manufacturing method therefor |
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JP2014187058A (en) * | 2013-01-14 | 2014-10-02 | Samsung Electro-Mechanics Co Ltd | Multilayer ceramic capacitor, mounting board for multilayer ceramic capacitor, and manufacturing method of multilayer ceramic capacitor |
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