Method for manufacturing conductive paste and method for manufacturing multilayer ceramic electronic components

Abstract

To provide a method for manufacturing an emulsion-state conductive paste and a method for manufacturing a multilayer ceramic electronic component which prevent a sheet attack phenomenon thereby preventing short circuit defects of the multilayer ceramic electronic component.SOLUTION: A method for manufacturing a conductive paste includes: preparing a first solution 10 including metal particles 11, a first solvent 12 and a binder 13; preparing a second solvent 20; preparing a surfactant 30 including core particles and an organic material disposed on surfaces of the core particles; and mixing the first solution, the second solvent and the surfactant to form a mixed solution 40.EFFECT: A sheet attack phenomenon can be prevented by providing an emulsion-state conductive paste. Short circuit defects of a multilayer ceramic electronic component can be prevented by preventing the sheet attack phenomenon.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a conductive paste and a method for manufacturing a multilayer ceramic electronic component.

Background Art

[0002] A multilayer ceramic capacitor (MLCC; Multilayer Ceramic Capacitor), which is one of multilayer ceramic electronic components, is a chip-type capacitor that is mounted on a printed circuit board of various electronic products such as video equipment such as a liquid crystal display (LCD) and a plasma display panel (PDP), a computer, a smartphone, and a mobile phone, and plays a role of charging or discharging electricity.

[0003] Such a multilayer ceramic capacitor (MLCC: Multi-Layered Ceramic Capacitor) is used as a component of various electronic devices due to its advantages of being small in size while ensuring high capacitance and being easy to mount.

[0004] The body of a multilayer ceramic capacitor can be formed by printing a conductive paste for an internal electrode on a ceramic green sheet to form an internal electrode pattern, laminating the ceramic green sheet on which the internal electrode pattern is formed, and then firing. At this time, the ceramic green sheet contains a ceramic powder such as barium titanate (BaTiO3) and an organic binder as main components, and the conductive paste for an internal electrode contains a metal powder, a solvent, a binder, a dispersant, and the like.

[0005] At this time, if the conductive paste for the internal electrodes contained an organic solvent, a problem arose in which a sheet attack phenomenon occurred, in which the organic solvent swelled or dissolved the organic binder contained in the ceramic green sheet. Such a sheet attack phenomenon led to problems such as a decrease in the insulating properties of the dielectric layer contained in the multilayer ceramic capacitor and an increase in the short-circuit rate. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Korean Published Patent Gazette No. 10-2021-0120006 [Overview of the project] [Problems that the invention aims to solve]

[0007] One of the several objectives of the present invention is to prevent the sheet attack phenomenon by providing a conductive paste in an emulsion state.

[0008] One of the several objectives of the present invention is to prevent short-circuit defects in multilayer ceramic electronic components by preventing the sheet attack phenomenon.

[0009] However, the objectives of the present invention are not limited to those described above and can be more easily understood in the process of describing specific embodiments of the present invention. [Means for solving the problem]

[0010] One embodiment of the present invention provides a method for producing a conductive paste, comprising the steps of: providing a first solution containing metal particles and a first solvent; providing a second solvent; providing core particles and a surfactant containing an organic substance formed on the surface of the core particles; and mixing the first solution, the second solvent, and the surfactant to form a mixed solution.

[0011] Another embodiment of the present invention provides a method for manufacturing a multilayer ceramic electronic component, comprising the steps of: providing a ceramic green sheet; applying a conductive paste to the ceramic green sheet, which contains a first solution containing metal particles and a first solvent, a second solvent, and a surfactant containing core particles and an organic substance formed on the surface of the core particles; stacking the ceramic green sheets coated with the conductive paste to form a ceramic laminate; and firing the ceramic laminate. [Effects of the Invention]

[0012] One of the various effects of the present invention is that by providing a conductive paste in an emulsion state, the sheet attack phenomenon can be prevented.

[0013] One of the various effects of the present invention is that by preventing the sheet attack phenomenon, short-circuit defects in multilayer ceramic electronic components can be prevented. [Brief explanation of the drawing]

[0014] [Figure 1] This diagram schematically illustrates a method for manufacturing a conductive paste according to one embodiment of the present invention. [Figure 2] This is an enlarged view showing area B in Figure 1. [Figure 3] This diagram schematically shows the manufacturing process of a surfactant containing ceramic particles (a) and the manufacturing process of a surfactant containing metal particles (b). [Figure 4] This is a schematic diagram of a ceramic green sheet coated with conductive paste. [Figure 5] Image (a) shows a ceramic green sheet coated with conductive paste manufactured according to a comparative example of the present invention, photographed with an optical microscope, and image (b) shows a ceramic green sheet coated with conductive paste manufactured according to an embodiment of the present invention, photographed with an optical microscope. [Figure 6]It is a process flowchart showing the manufacturing process of a multilayer ceramic electronic component according to an embodiment of the present invention. [Figure 7] It is a perspective view schematically showing a multilayer ceramic electronic component manufactured according to an embodiment of the present invention. [Figure 8] It is a perspective view schematically showing the main body of a multilayer ceramic electronic component. [Figure 9] It is a cross-sectional view schematically showing a cut cross-section along line I-I' in FIG. 7. [Figure 10] It is a cross-sectional view schematically showing a cut cross-section along line II-II' in FIG. 7.

Mode for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to specific embodiments and the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Also, the embodiments of the present invention are provided to more fully explain the present invention to an ordinary technician. Therefore, the shape and size of elements in the drawings can be exaggerated for a clearer explanation, and elements denoted by the same reference numerals in the drawings are the same elements.

[0016] And, in the drawings, parts not related to the explanation are omitted for clearly explaining the present invention, and the sizes and thicknesses of each configuration shown in the drawings are arbitrarily shown for convenience of explanation, so the present invention is not necessarily limited to what is shown in the drawings. For components having the same function within the scope of the same idea, the same reference numerals are used for explanation. Further, throughout the specification, when a certain part says that it "includes" a certain component, this means that, unless otherwise stated to the contrary, it does not exclude other components, but can further include other components.

[0017] In the drawings, the first direction can be defined as the length L direction, the second direction as the thickness T direction or the lamination direction, and the third direction as the width W direction.

[0018] <Method for Manufacturing Conductive Paste> FIG. 1 schematically shows a method for manufacturing a conductive paste according to an embodiment of the present invention. FIG. 2 is an enlarged view showing the B region of FIG. 1. FIG. 3 schematically shows the manufacturing process (a) of a surfactant containing ceramic particles and the manufacturing process (b) of a surfactant containing metal particles. FIG. 4 schematically shows a ceramic green sheet coated with the conductive paste.

[0019] Hereinafter, referring to FIGS. 1 to 4, a method for manufacturing a conductive paste according to an embodiment of the present invention will be described in detail.

[0020] A method for manufacturing a conductive paste according to an embodiment of the present invention includes a step of providing a first solution 10 containing metal particles 11 and a first solvent 12, a step of providing a second solvent 20, a step of providing a surfactant 30 containing core particles 31 and an organic substance 32 formed on the surface of the core particles 31, and a step of mixing the first solution 10, the second solvent 20, and the surfactant 30 to form a mixed solution 40.

[0021] The first solution 10 can be formed by adding metal particles 11 to the first solvent 12. At this time, the metal particles 11 may be, for example, one or more of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof, and more preferably may contain nickel (Ni). At this time, the average diameter of the metal particles 11 contained in the first solution 10 may be 150 to 300 nm, but the present invention is not limited thereto. The average diameter of the metal particles 11 can be measured by various methods such as a diameter measurement method or an ASTM crystal grain size test method etc.

[0022] The first solvent 12 may be a hydrophobic solvent and may include one or more of acetate solvents, terpene solvents, hydrocarbon solvents, carboxylic acid solvents, and ester solvents, but the present invention is not limited thereto. Examples of the acetate solvents include dihydroterpinyl acetate, isobornyl acetate, isobornyl propionate, isobornyl butyrate, isobornyl isobutylate, ethylene glycol monobutyl ether acetate, and dipropylene glycol methyl ether acetate. Examples of the terpene solvents include terpineol and dihydroterpineol. The hydrocarbon solvent may be, for example, one or more of hexadecane and octadecane. However, the present invention is not limited thereto.

[0023] The first solution 10 may contain a binder 13. The binder 13 refers to an organic component that contributes to improving the bonding between particles contained in the conductive paste. The binder 13 is not limited to polyvinyl butyral, cellulose resin, etc., can be used. The content of the binder 13 is not limited to this, but for example, it may be 1 to 20 parts by weight per 100 parts by weight of metal particles 11. In this case, the first solution 10 can exist in a form in which the metal particles 11 and the binder 13 are uniformly dispersed in the first solvent 12.

[0024] The second solvent 20 may be, for example, a hydrophilic solvent, such as water (H2O) and / or dimethyl sulfoxide, but the present invention is not limited thereto.

[0025] The surfactant 30 is amphiphilic and can exist at the interface between two immiscible solvents, such as a hydrophilic solvent and a hydrophobic solvent. For example, the surfactant 30 can exist at the interface between a first solution 10 containing a first solvent 12, which is a hydrophobic solvent, and a second solvent 20, which is a hydrophilic solvent. In this case, the surfactant 30's presence at the interface between the immiscible first solution 10 and second solvent 20 allows the first solution 10 to be uniformly dispersed within the second solvent 20. As a result, the mixed solution 40, which is a mixture of the first solution 10, the second solvent 20, and the surfactant, can maintain a stable emulsion state. Further details regarding the surfactant 30 will be described later.

[0026] A method for producing a conductive paste according to one embodiment of the present invention may further include the step of emulsifying a mixed solution 40 by sonication. By stirring the mixed solution 40 by sonication, the first solution 10 can be uniformly dispersed in the second solvent 20. As a result, the mixed solution 40 can be in an oil-in-water emulsion state in which the first solution 10 is dispersed in the second solvent 20.

[0027] As described above, when the conductive paste contains an organic solvent, a sheet attack phenomenon occurs in which the organic solvent swells or dissolves the organic binder contained in the ceramic green sheet CS. Such a sheet attack phenomenon causes problems such as reducing the insulating properties of the dielectric layer contained in the multilayer ceramic electronic component and increasing the short-circuit rate.

[0028] In contrast, a conductive paste manufactured according to one embodiment of the present invention can exist in an oil-in-water emulsion state in which the first solution 10 is uniformly dispersed in the second solvent 20. Therefore, for example, the first solvent 12, which is a hydrophobic solvent, does not come into direct contact with the ceramic green sheet CS, so even if the conductive paste is applied to the ceramic green sheet CS, the first solvent 12 will not swell or dissolve the organic binder contained in the ceramic green sheet CS. Furthermore, for example, even if the second solvent 20, which is a hydrophilic solvent, comes into direct contact with the ceramic green sheet CS, the hydrophilic second solvent 20 does not have compatibility with the organic binder contained in the ceramic green sheet CS, thereby preventing the sheet attack phenomenon.

[0029] Even while the conductive paste applied to the ceramic green sheet CS is drying, the surfactant 30 present at the interface between the first solution 10 and the second solvent 20 allows the conductive paste to maintain an emulsion state. As a result, even as the first solvent 12 and the second solvent 20 dry and are removed, the metal particles 11, binder 13, and surfactant 30 remain in a phase-separated state from the ceramic green sheet CS. Consequently, the dried conductive paste coating can have a form in which aggregates of numerous metal particles 11 and the binder 13 and surfactant 30 present between the metal particles 11 are uniformly dispersed.

[0030] Therefore, even when multiple ceramic green sheets CS coated with conductive paste are laminated, the sheet attack phenomenon against the already laminated ceramic green sheets CS can be prevented.

[0031] In one embodiment, the volume ratio of the first solution 10 to the volume of the second solvent 20 may be 1 or less. For example, when the first solvent 12 is a hydrophobic solvent and the second solvent 20 is a hydrophilic solvent, the oil-in-water emulsion state in which the particles of the first solution 10 are dispersed in the second solvent 20 can be stably maintained when the above conditions are met. The lower limit of the volume ratio of the first solution 10 to the volume of the second solvent 20 is not particularly limited, but it may be 0.01 or more, or 0.1 or more, considering the conductivity of the internal electrodes.

[0032] The surfactant 30 comprises core particles 31 and an organic substance 32 formed on the surface of the core particles 31. Here, the core particles 31 are not particularly limited, as long as they contain binding sites A to which the organic substance 32 can bind, but for example, they may include one or more of ceramic particles, polymer particles, semiconductor particles, and metal particles. Such a core particle-organic substance form surfactant 30 has properties similar to conventional amphiphilic organic substance form surfactants, but has a higher adsorption energy at the interface between the first solution 10 and the second solvent 20, can more stably maintain the conductive paste in emulsion state, and can perform a wider range of functions than conventional surfactants by having properties depending on the type of core particles 31.

[0033] For example, the core particles 31 of the surfactant 30 may include barium titanate (BaTiO3) as the ceramic particles. When the core particles 31 are ceramic particles, more specifically barium titanate (BaTiO3), they can also act as a co-material to control the sintering shrinkage of the metal particles 11 during firing. That is, the surfactant 30 can disperse the metal particles 11 in the first solution 10, maintaining the conductive paste in an emulsion state while also acting as a co-material during firing.

[0034] Furthermore, if the core particles 31 of the surfactant 30 are, for example, metal particles, the surfactant 30 functions to disperse the metal particles 11 in the first solution 10, thereby improving the conductivity of the internal electrodes by including the electrically conductive core particles 31 while maintaining the conductive paste in an emulsion state. The metal particles as the core particles 31 of the surfactant 30 are not particularly limited, but for example, they may include one or more of gold (Au), silver (Ag), and platinum (Pt).

[0035] Furthermore, if the core particles 31 of the surfactant 30 are polymer particles, there is an advantage in that they contain many binding sites A, such as hydroxyl groups (-OH), to which organic substances 32 can be bound. If the core particles 31 are semiconductor particles, there is an advantage in that they are used in various fields such as solar cells and are commercially viable. The above semiconductor particles are not particularly limited, but for example, they may include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, InP, InAs, and InSb.

[0036] In this case, the average diameter of the core particles 31 may be 5 to 100 nm. If the average diameter of the core particles 31 exceeds 100 nm, the large size of the core particles 31 may reduce the ability to maintain the emulsion state.

[0037] Furthermore, the shape of the core particles 31 is not particularly limited, and may be one or more of the following: cylinder, rectangular prism, triangular prism, pentagonal prism, hexagonal prism, octagonal prism, sphere, hemisphere, part of a sphere, ellipsoid, semi-ellipsoid, part of an ellipsoid, square pyramid, square bicornuate, square truncated pyramid, triangular pyramid, triangular bicornuate, triangular truncated pyramid, cone, truncated cone, ring, and cube. Any shape is acceptable as long as the surfactant 30 can be amphiphilic.

[0038] Multiple organic substances 32 of the surfactant 30 can be formed on the surface of the core particles 31, and the organic substances 32 can chemically bond to the core particles 31 via binding sites A within the core particles 31. In this case, in order to modify the surface of the core particles 31 so that the surfactant 30 has amphiphilic properties, the organic substances 32 may include one or more of hydrophilic organic substances, hydrophobic organic substances, and amphiphilic organic substances.

[0039] For example, if the core particles 31 are hydrophilic, the surfactant 30 can be made amphiphilic by forming a hydrophobic organic substance 32 on the surface of the core particles 31.

[0040] More specifically, if the core particle 31 is hydrothermally synthesized barium titanate (BaTiO3), then hydroxyl groups (-OH) can participate in the reaction during the hydrothermal synthesis process. This allows hydroxyl groups to be substituted for oxygen sites in the perovskite crystal structure of barium titanate. As a result, barium titanate can be hydrophilic overall. In this case, the hydroxyl groups of barium titanate can act as the aforementioned bonding sites A, and by bonding the hydroxyl groups to hydrophobic organic substances capable of hydrogen bonding, the surfactant 30 in core particle-organic substance form can be amphiphilic overall. The amphiphilic surfactant 30 can be present at the interface between the first solution 10 and the second solvent 20, and can stably maintain the conductive paste in emulsion state. On the other hand, if the core particles 31 are polymer particles, they contain many hydroxyl groups that can act as binding sites, and the surfactant 30 can be amphiphilic by hydrogen bonding of hydrophilic organic substances, hydrophobic organic substances and / or amphiphilic organic substances to the hydroxyl groups.

[0041] Furthermore, if the core particle 31 is a metal particle M, there does not need to be a binding site to which the organic substance 32 can bind. In this case, after chemically binding ligand RD as a binding site A to the surface of the core particle 31, the organic substance 32 that can chemically bind to ligand RD can be formed on the surface of the core particle 31. More specifically, a hydrophilic ligand and / or hydrophobic ligand can be formed on the surface of the metal particle M by a wet reduction method using a reducing agent, a plasma process, an arc discharge method, etc., and then the organic substance 32 that can chemically bind to ligand RD can be formed on the surface of the metal particle M, thereby forming an amphiphilic surfactant 30.

[0042] The hydrophilic ligand RD may include, for example, one or more of polyethylene glycol, monosaccharide phosphate, citric acid, and betaine. Alternatively, the hydrophobic ligand RD may be a fatty acid or fatty acid amine such as caproic acid, stearic acid, oleic acid, oleylamine, butylamine, and octylamine.

[0043] If, for example, a hydrophilic ligand RD is formed on the core particle 31, an amphiphilic surfactant 30 can be formed by binding a hydrophobic organic substance 32 capable of hydrogen bonding with the hydrophilic ligand. Alternatively, after binding the amphiphilic organic substance 32 to the core particle 31, the ligand RD can be dissolved and removed, but the present invention is not limited thereto.

[0044] The hydrophilic organic substance 32 is preferably an organic substance capable of hydrogen bonding, and may be one or more of polyvinyl alcohol, polyacrylamide, polyethylene glycol, and polyvinylpyrrolidone, but the present invention is not limited thereto. The hydrophobic organic substance 32 may be one or more of polylactide, polycaprolactone, and polypeptide, but the present invention is not limited thereto. The amphiphilic organic substance 32 may be sodium dodecyl sulfate, but the present invention is not limited thereto.

[0045] The surfactant 30 in the form of core particles and organic matter can be produced by chemically bonding the organic matter 32 to the core particles 31 via bonding sites A within the core particles 31, as described above. For example, it can be formed by adding the organic matter 32 to a solution in which the core particles 31 are dissolved and heating it at a certain temperature, but the present invention is not limited thereto. In this case, the surfactant 30 may be contained in an amount of 0.1 to 25 parts by weight per 100 parts by weight of the second solvent 20, but the present invention is not limited thereto.

[0046] Figure 5 shows images (a) of a ceramic green sheet coated with conductive paste produced by the comparative example of the present invention, taken with an optical microscope, and (b) of a ceramic green sheet coated with conductive paste produced by the embodiment of the present invention, taken with an optical microscope. The comparative example of the present invention involves applying a conductive paste, in which metal particles are dispersed in a hydrophobic organic solvent, onto a ceramic green sheet.

[0047] Referring to Figure 5, it can be seen that the sheet attack phenomenon occurred in the case of the ceramic green sheet coated with the conductive paste manufactured by the comparative example. This is because, in the case of the comparative example which contains only an organic solvent, the organic solvent swells or dissolves the organic binder contained in the ceramic green sheet. In contrast, it can be seen that the sheet attack phenomenon does not occur in the case of the ceramic green sheet coated with the conductive paste manufactured by the example of the present invention. This is because the first solvent, which is a hydrophobic solvent, does not come into direct contact with the ceramic green sheet, while the second solvent, which is a hydrophilic solvent that is not compatible with the organic binder contained in the ceramic green sheet, comes into direct contact with the ceramic green sheet, thereby preventing the sheet attack phenomenon.

[0048] <Manufacturing method for multilayer ceramic electronic components> A conductive paste manufactured according to one embodiment of the present invention can be used for the purpose of manufacturing internal electrodes for multilayer ceramic electronic components.

[0049] Figure 6 is a process flowchart showing the manufacturing process of a multilayer ceramic electronic component according to one embodiment of the present invention; Figure 7 is a schematic perspective view showing a multilayer ceramic electronic component manufactured according to one embodiment of the present invention; Figure 8 is a schematic perspective view showing the body of the multilayer ceramic electronic component; Figure 9 is a schematic cross-sectional view showing a cross section along the line I-I' in Figure 7; and Figure 10 is a schematic cross-sectional view showing a cross section along the line II-II' in Figure 7.

[0050] Referring to Figures 6 to 10, a method for manufacturing a multilayer ceramic electronic component according to one embodiment of the present invention includes the steps of: providing a ceramic green sheet (P1); applying a conductive paste to the ceramic green sheet, which contains a first solution containing metal particles and a first solvent, a second solvent, and a surfactant containing core particles and an organic substance formed on the surface of the core particles (P2); stacking the ceramic green sheets to which the conductive paste has been applied to form a ceramic laminate (P3); and firing the ceramic laminate (P4).

[0051] The following describes in detail, step by step, a method for manufacturing a multilayer ceramic electronic component according to one embodiment of the present invention. First, a ceramic green sheet containing ceramic powder is provided (P1). The ceramic green sheet can be manufactured by mixing ceramic powder, a binder, a solvent, etc. to produce a slurry, and then fabricating the slurry into a sheet with a thickness of several μm using a doctor blade method. The ceramic green sheet can be fired to form a dielectric layer 111.

[0052] The average thickness of the ceramic green sheet may be 0.6 μm or less, and the average thickness of the dielectric layer 111 after firing may be 0.4 μm or less. In the case of a method for manufacturing a multilayer ceramic electronic component according to one embodiment of the present invention, by applying a conductive paste in emulsion state onto the ceramic green sheet, the sheet attack phenomenon can be prevented even if the ceramic green sheet has a very thin thickness, and the occurrence of a short circuit due to contact between the first internal electrode 121 and the second internal electrode 122, which are laminated with a thin dielectric layer 111 in between, can be prevented.

[0053] Next, a conductive paste is applied onto the ceramic green sheet, comprising a first solution 10 containing metal particles 11 and a first solvent 12, a second solvent 20, and a surfactant 30 containing core particles 31 and an organic substance 32 formed on the surface of the core particles 31 (P2).

[0054] In this case, the first solvent 12 can be a hydrophobic solvent, and the second solvent 20 can be a hydrophilic solvent. That is, as described above, the conductive paste may be in an oil-in-water emulsion state in which the first solution 10 containing a hydrophobic solvent is dispersed in the second solvent 20 which is a hydrophilic solvent.

[0055] As a result, the hydrophobic first solvent 12 does not come into direct contact with the ceramic green sheet, so even if the conductive paste is applied to the ceramic green sheet, the first solvent 12 will not swell or dissolve the organic binder contained in the ceramic green sheet. Furthermore, even if the second solvent 20 comes into direct contact with the ceramic green sheet, the hydrophilic second solvent 20 does not have compatibility with the organic binder contained in the ceramic green sheet, thus preventing the sheet attack phenomenon.

[0056] Therefore, even if multiple layers of ceramic green sheets coated with the above conductive paste are laminated, the sheet attack phenomenon against the previously laminated ceramic green sheets can be prevented.

[0057] Next, ceramic green sheets coated with the conductive paste can be stacked to form a ceramic laminate (P3). At this time, the ceramic laminate can be compressed and bonded in the stacking direction. Furthermore, the ceramic laminate can be cut into regions corresponding to a single electronic component to form chips.

[0058] Next, the ceramic laminate can be fired (P4). That is, by firing the ceramic laminate, which has been cut into regions corresponding to one electronic component, a main body 110 including a dielectric layer 111 and internal electrodes 121 and 122 can be formed. The firing process can be carried out in a reducing atmosphere. The firing process can be carried out by adjusting the heating rate, and is not limited to this, but the heating rate may be 30°C / 60s to 50°C / 60s at 700°C or less.

[0059] Next, external electrodes 131 and 132, which are connected to the internal electrodes 121 and 122, can be formed on the outside of the main body 110. The method for forming the external electrodes 131 and 132 is not particularly limited, but they can be formed by dipping the main body 110 into a conductive paste for external electrodes containing conductive metal and glass components, transferring a sheet containing conductive metal and glass components, or applying and curing a conductive paste for external electrodes containing conductive metal and resin components.

[0060] The method for manufacturing multilayer ceramic electronic components according to another embodiment of the present invention described above may have a configuration similar to that of the conductive paste embodiment according to the embodiment described above. Therefore, the description that overlaps with the embodiment described above will be omitted.

[0061] <Multilayer ceramic electronic components> The multilayer ceramic electronic component 100 manufactured by the manufacturing method of a multilayer ceramic electronic component according to the embodiment of the present invention described above includes a main body 110 including a dielectric layer 111 and internal electrodes 121 and 122, and external electrodes 131 and 132 disposed outside the main body 110.

[0062] There are no particular limitations on the specific shape of the main body 110, but as shown in the figure, the main body 110 can be a hexahedron or a similar shape. Due to the shrinkage of the ceramic powder contained in the main body 110 during the firing process and the polishing of the corners, the main body 110 may not be a perfectly straight hexahedron, but it may be substantially hexahedron-shaped.

[0063] The main body 110 may have a first and second surface 1, 2 facing each other in the first direction, a third and fourth surface 3, 4 connected to the first and second surfaces 1, 2 facing each other in the second direction, and a fifth and sixth surface 5, 6 connected to the first to fourth surfaces 1, 2, 3, 4 facing each other in the third direction.

[0064] The main body 110 may be formed by alternately stacking dielectric layers 111 and internal electrodes 121 and 122. The multiple dielectric layers 111 forming the main body 110 are in a fired state, and the boundaries between adjacent dielectric layers 111 can be integrated to such an extent that they are difficult to confirm without using a scanning electron microscope (SEM).

[0065] In this case, the average thickness of the dielectric layer 111 may be 0.4 μm or less. The average thickness of the dielectric layer 111 can be measured by scanning the cross-sections of the main body 110 in the first and second directions with a scanning electron microscope at 10,000x magnification. More specifically, the thickness of a single dielectric layer 111 can be measured at multiple points, for example, at 30 points equally spaced in the first direction, and the average value can be measured. Furthermore, by extending this measurement of the average value to a large number of dielectric layers 111, the average thickness of the dielectric layer 111 can be further generalized.

[0066] The main body 110 may include a capacitance forming section Ac disposed inside the main body 110, comprising a plurality of first internal electrodes 121 and a plurality of second internal electrodes 122 arranged facing each other with a dielectric layer 111 in between, to form a capacitance; a first cover section 112 disposed above the capacitance forming section Ac; and a second cover section 113 disposed below the capacitance forming section Ac. The first cover section 112 and the second cover section 113 can be formed by stacking a single dielectric layer or two or more dielectric layers in a second direction on the upper and lower surfaces of the capacitance forming section Ac, respectively, and can essentially serve to prevent damage to the internal electrodes due to physical or chemical stress.

[0067] The main body 110 may further include margin portions 114 and 115 arranged on the side surface of the capacitance forming portion Ac with respect to the third direction. The margin portions 114 and 115 may include a first margin portion 114 arranged on the fifth surface 5 of the main body 110 and a second margin portion 115 arranged on the sixth surface 6. The margin portions 114 and 115 may represent the regions between both ends of the internal electrodes 121 and 122 and the interface of the main body 110 in cross-sections obtained by cutting the main body 110 in the second and third directions. The margin portions 114 and 115 can essentially serve to prevent damage to the internal electrodes 121 and 122 due to physical or chemical stress. The margin portions 114 and 115 may be formed by applying conductive paste to the ceramic green sheet, except where the margin portions are formed, to form the internal electrodes. Alternatively, after lamination, the internal electrodes 121 and 122 can be cut so that they are exposed on the fifth and sixth surfaces 5 and 6 of the main body, and then a single dielectric layer or two or more dielectric layers can be laminated on both sides of the capacitance forming portion Ac in the third direction.

[0068] The internal electrodes 121 and 122 may be arranged alternately with the dielectric layer 111, and a plurality of first internal electrodes 121 and a plurality of second internal electrodes 122 may be arranged facing each other with the dielectric layer 111 in between. For example, a plurality of first internal electrodes 121 can be separated from the second surface 2 and exposed via the first surface 1. Similarly, a plurality of second internal electrodes 122 can be separated from the first surface 1 and exposed via the second surface 2. The plurality of first internal electrodes 121 and a plurality of second internal electrodes 122 may be electrically isolated from each other by the dielectric layer 111 arranged between them. The conductive metals included in the internal electrodes 121 and 122 may be one or more of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof, and the present invention is not limited thereto.

[0069] In this case, the average thickness of the internal electrodes 121 and 122 may be 0.4 μm or less. The average thickness of the internal electrodes 121 and 122 can be measured by scanning the cross-sections of the main body 110 in the first and second directions with a scanning electron microscope at 10,000x magnification. More specifically, the thickness of a single internal electrode can be measured at multiple points, for example, at 30 points equally spaced in the first direction, and the average value can be measured. By extending this measurement of the average value to a large number of internal electrodes, the average thickness of the internal electrodes can be further generalized.

[0070] External electrodes 131 and 132 are arranged on the first and second surfaces 1 and 2 of the main body 110, and can be partially extended to the third, fourth, fifth, and sixth surfaces 3, 4, 5, and 6, respectively. External electrodes 131 and 132 may include first external electrodes 131 and second external electrodes 132 connected to a plurality of first internal electrodes 121 and a plurality of second internal electrodes 122, respectively.

[0071] The external electrodes 131 and 132 may be formed using any material that has electrical conductivity, such as a metal, and the specific material may be determined considering electrical properties, structural stability, etc. Furthermore, they may have a multilayer structure. For example, the external electrodes 131 and 132 may include first electrode layers 131a and 132a placed on the main body 110 and second electrode layers 131b and 132b placed on the first electrode layers.

[0072] The first electrode layers 131a and 132a may be fired electrodes containing a conductive metal and glass, or resin-based electrodes containing a conductive metal and resin. Here, the resin can be an insulating resin, for example, epoxy resin, but the present invention is not limited thereto. The conductive metal contained in the first electrode layers 131a and 132a may include copper (Cu), nickel (Ni), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), lead (Pb), and / or alloys containing these, and preferably contains copper (Cu) and / or nickel (Ni), but is not limited thereto.

[0073] The type of the second electrode layers 131b and 132b is not particularly limited and may be a plating layer containing nickel (Ni), tin (Sn), palladium (Pd), and / or an alloy containing these, and may be formed in multiple layers. The second electrode layers 131b and 132b may be, for example, a nickel (Ni) plating layer or a tin (Sn) plating layer, and may be formed in a form in which the nickel (Ni) plating layer and the tin (Sn) plating layer are formed sequentially. Furthermore, the second electrode layers 131b and 132b may contain multiple nickel (Ni) plating layers and / or multiple tin (Sn) plating layers.

[0074] The present invention is not limited by the embodiments described above or the accompanying drawings, but is limited by the claims provided. Therefore, within the scope of the present invention, various forms of substitution, modification, and alteration are possible by persons with ordinary skill in the art, without departing from the technical idea of ​​the invention as described in the claims, and these also fall within the scope of the present invention.

[0075] The expression "an embodiment" as used in this disclosure does not mean that each embodiment is identical to another, but is provided to highlight and explain the unique and distinct characteristics of each embodiment. However, the embodiments presented above are not excluded from being realized in combination with the characteristics of other embodiments. For example, even if a matter described in one embodiment is not described in another embodiment, it can be understood as a description related to the other embodiment, unless there is a contradictory or contrary description of that matter in the other embodiment. [Explanation of symbols]

[0076] 10: Solution 1 11: Metal particles 12: First solvent 20: Second solvent 30: Surfactants 31: Core Particle 32:Organic substances 40: Mixed solution CS: Ceramic Green Sheet RD: Ligand 100: Multilayer ceramic electronic components 110: Main unit 111: Dielectric layer 112, 113: Cover section 114, 115: Margin section 121, 122: Internal electrode 131, 132: External electrode 131a, 132a: first electrode layer 131b, 132b: Second electrode layer

Claims

1. A step of providing a first solution containing metal particles and a first solvent, The step of providing the second solvent, A step of providing core particles and a surfactant containing an organic substance formed on the surface of the core particles, A method for producing a conductive paste, comprising the step of mixing the first solution, the second solvent, and the surfactant to form a mixed solution.

2. A method for producing a conductive paste according to claim 1, further comprising the step of ultrasonically treating the mixed solution to form an emulsion.

3. The method for producing a conductive paste according to claim 1, wherein the first solvent is a hydrophobic solvent and the second solvent is a hydrophilic solvent.

4. The method for producing a conductive paste according to claim 1, wherein the volume ratio of the first solution to the volume of the second solvent is 1 or less.

5. The method for producing a conductive paste according to claim 1, wherein the core particles include one or more of ceramic particles, polymer particles, semiconductor particles, and metal particles.

6. The method for producing a conductive paste according to claim 1, wherein the organic substance comprises one or more of a hydrophilic organic substance, a hydrophobic organic substance, and an amphiphilic organic substance.

7. The ceramic particles of the surfactant are barium titanate (BaTiO ３ A method for producing a conductive paste according to any one of claims 1 to 6, including )

8. A method for producing a conductive paste according to any one of claims 1 to 6, wherein the metal particles of the surfactant include one or more of gold (Au), silver (Ag), and platinum (Pt).

9. A method for producing a conductive paste according to any one of claims 1 to 6, wherein the average diameter of the core particles is 5 to 100 nm.

10. The stage of installing the ceramic green sheet, The steps include applying a conductive paste onto the ceramic green sheet, a first solution containing metal particles and a first solvent, a second solvent, and a surfactant containing core particles and an organic substance formed on the surface of the core particles, The steps include: forming a ceramic laminate by stacking ceramic green sheets coated with the conductive paste, A method for manufacturing a multilayer ceramic electronic component, comprising the step of firing the ceramic laminate.

11. The method for manufacturing a multilayer ceramic electronic component according to claim 10, wherein the first solvent is a hydrophobic solvent and the second solvent is a hydrophilic solvent.

12. The method for manufacturing a multilayer ceramic electronic component according to claim 10, wherein the conductive paste is in an oil-in-water emulsion state.

13. The method for manufacturing a multilayer ceramic electronic component according to claim 10, wherein the core particles are one or more of ceramic particles, polymer particles, semiconductor particles, and metal particles.

14. The method for manufacturing a multilayer ceramic electronic component according to claim 10, wherein the organic substance comprises one or more of a hydrophilic organic substance, a hydrophobic organic substance, and an amphiphilic organic substance.

15. The ceramic particles of the surfactant are barium titanate (BaTiO ３ A method for manufacturing a multilayer ceramic electronic component according to any one of claims 10 to 14, including )

16. The method for manufacturing a multilayer ceramic electronic component according to any one of claims 10 to 14, wherein the metal particles of the surfactant include one or more of gold (Au), silver (Ag), and platinum (Pt).

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