Method for manufacturing laminated ceramic component

Abstract

Provided is a method for manufacturing a laminated ceramic member capable of forming an external electrode in which a moon-shaped shape is suppressed. This method for manufacturing a laminated ceramic member is provided with a first step, a second step, a third step, a fourth step, and a fifth step. In the first step, a laminate in which a plurality of ceramic green sheets and a plurality of internal electrode paste layers are laminated is prepared. In the second step, the laminate is fired to form a ceramic body. In the third step, the surface of the ceramic body is subjected to plasma treatment. In the fourth step, an external electrode paste is adhered to a part of the surface of the ceramic body after the third step. In the fifth step, the ceramic body after the fourth step is heat-treated to form an external electrode (14).

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a laminated ceramic component. Specifically, it relates to a method for manufacturing a laminated ceramic component including a step of forming an external electrode on the surface of a ceramic green body. Background Art

[0002] Laminated varistors are used for the following purposes: to protect various electronic devices, electronic components, etc. from abnormal voltages caused by lightning surges, static electricity, etc., and in addition, to prevent malfunction of electronic devices, electronic components, etc. caused by noise generated in the circuit.

[0003] In such laminated ceramic components as laminated varistors, an external electrode is formed by applying an external electrode paste on a hydrophilic ceramic green body and then performing firing.

[0004] The external electrode paste is applied by dipping one end face of the ceramic green body in the external electrode paste. However, since the ceramic green body has hydrophilicity, wetting spread occurs during the period when the ceramic green body is dipped in the external electrode paste. Therefore, the shape of the formed external electrode becomes a crescent shape. As a result, there are problems such as a large deviation in the size of the external electrode or difficulty in matching a given size value of the external electrode.

[0005] Patent Document 1 describes a method for manufacturing a ceramic electronic component including the following steps: in a ceramic body having a substantially rectangular parallelepiped shape with a conductive metal layer inside and a part of the conductive metal layer led out from two opposed end faces, a pair of external electrodes are formed from the two opposed end faces over at least any side face of the ceramic body, and the interval between the side end portions on the side face is shorter than the interval between the central portions. In this manufacturing method, after immersing a laminated chip in a treatment liquid such as a silicone-based release agent or a fluorine-based release agent that has been built up to a desired concentration, dehydration and heat treatment are performed, and then an external electrode paste is applied, thereby suppressing the crescent shape of the external electrode and enabling the interval between the side end portions in a pair of external electrodes to be shorter than the interval between the central portions as described above.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-91800 Summary of the Invention

[0009] Problems to be Solved by the Invention

[0010] However, in the method of using a mold release agent as in Patent Document 1, there is a step of immersing in a liquid, so a drying step becomes necessary, and thus there is a problem that the manufacturing process becomes complicated. In addition, in the manufacture of a multilayer varistor, an external electrode is sometimes formed on the surface of a ceramic green body on an insulating layer with higher hydrophilicity.

[0011] An object of the present disclosure is to provide a method for manufacturing a multilayer ceramic component capable of forming an external electrode with a suppressed crescent shape.

[0012] Means for Solving the Problem

[0013] The method for manufacturing a multilayer ceramic component according to one embodiment of the present disclosure includes a first step, a second step, a third step, a fourth step, and a fifth step. The first step is a step of preparing a laminate obtained by laminating a plurality of ceramic green sheets and a plurality of internal electrode pastes. The second step is a step of firing the laminate to form a ceramic green body. The third step is a step of performing plasma treatment on the surface of the ceramic green body. The fourth step is a step of attaching an external electrode paste to a part of the surface of the ceramic green body after the third step. The fifth step is a step of performing heat treatment on the ceramic green body after the fourth step to form an external electrode.

[0014] Advantageous Effects of the Invention

[0015] According to the present disclosure, it is possible to suppress the wetting spread of the external electrode paste by a simple method, thereby forming an external electrode with a suppressed crescent shape, and thus it becomes easy to control the coating size of the external electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A is a schematic perspective view of an example of a multilayer ceramic component manufactured by the manufacturing method of the present disclosure.

[0017] Figure 1B is a cross-sectional view taken along line IB - IB of the multilayer ceramic component manufactured by the manufacturing method of the present disclosure.

[0018] Figure 2A is a schematic partial perspective view of another example of the multilayer ceramic component manufactured by the manufacturing method of the present disclosure.

[0019] Figure 2B is a cross-sectional view taken along line IIB - IIB of the multilayer ceramic component manufactured by the manufacturing method of the present disclosure.

[0020] Figure 3 is a schematic top view showing the crescent shape of the external electrode in the multilayer ceramic component.

[0021] Description of Reference Numerals

[0022] 1 Multilayer ceramic component

[0023] 11 Ceramic green body

[0024] 12A, 12B, 12C Internal electrodes

[0025] 13 Insulating layer

[0026] 14A, 14B, 14C, 14D External electrodes. Detailed implementation manners

[0027] 1. Outline

[0028] Hereinafter, a method for manufacturing a multilayer ceramic component according to an embodiment of the present disclosure will be described with reference to the accompanying drawings. In addition, the drawings described in the following embodiments are schematic drawings, and the ratios of the sizes and thicknesses of the respective components in the drawings do not necessarily reflect the actual size ratios.

[0029] The multilayer ceramic component 1 manufactured by the manufacturing method of the present embodiment includes a ceramic green body 11, a plurality of internal electrodes 12, and a plurality of external electrodes 14. For example, a multilayer varistor, a multilayer thermistor, a multilayer ceramic capacitor, etc. can be cited.

[0030] In this multilayer ceramic component 1, the ceramic green body 11 has end faces S11, S12 that face each other in the first direction (X direction), side faces S21, S22 that face each other in the second direction (Y direction) that intersects the first direction (X direction), and main faces S31, S32 that face each other in the third direction (Z direction) that intersects the first direction (X direction) and the second direction (Y direction).

[0031] Figure 1A And Figure 1B is a diagram showing an example of the multilayer ceramic component 1 manufactured by the manufacturing method of the present embodiment. Figure 1A is a schematic perspective view of an example of the multilayer ceramic component 1 manufactured by the manufacturing method of the present embodiment. Figure 1B is a cross-sectional view taken along the line IB - IB of the multilayer ceramic component 1 manufactured by the manufacturing method of the present disclosure. As Figure 1A shown, in the multilayer ceramic component 1, each face of the external electrodes 14 (14A, 14B) formed on all of the main faces S31, S32 and a part of the side faces S21, S22 is substantially rectangular in a top view. As Figure 1B shown, this multilayer ceramic component 1 includes a ceramic green body 11, a pair of internal electrodes 12A, 12B, an insulating layer 13, and a pair of external electrodes 14A, 14B.

[0032] In addition, Figure 2A And Figure 2BThis is a diagram showing another example of the multilayer ceramic component 1 manufactured by the manufacturing method of the present embodiment. Figure 2A This is a schematic partial perspective view of another example of the multilayer ceramic component 1 manufactured by the manufacturing method of the present disclosure. Figure 2B This is a cross-sectional view taken along the line IIB-IIB of the multilayer ceramic component 1 manufactured by the manufacturing method of the present disclosure. In Figure 2A In the multilayer ceramic component 1, each surface of the external electrodes (14C, 14D) formed on a part of the side surfaces S21, S22 and a part of the main surfaces S31, S32 is substantially rectangular in plan view. As Figure 2B shown, the multilayer ceramic component 1 includes a ceramic green body 11, three internal electrodes 12A, 12B, 12C, an insulating layer 13, and two pairs of external electrodes 14A, 14B, 14C, 14D.

[0033] As Figure 1A and Figure 2B shown, regarding the external electrodes 14 (14A, 14B, 14C, 14D) in the multilayer ceramic component 1 obtained by the manufacturing method of the present embodiment, the crescent shape is suppressed. According to the manufacturing method of the present embodiment, it is possible to form the external electrodes 14 with the crescent shape suppressed on various surfaces such as the end surfaces S11, S12, the side surfaces S21, S22, and the main surfaces S31, S32 on the ceramic green body 11 or the insulating layer 13.

[0034] The manufacturing method of the multilayer ceramic component of the present embodiment includes a first step, a second step, a third step, a fourth step, and a fifth step. In the first step, a laminate (hereinafter, also referred to as laminate L) obtained by laminating a plurality of ceramic green sheets and a plurality of internal electrode pastes is prepared. In the second step, the laminate L is fired to form the ceramic green body 11. In the third step, the surface of the ceramic green body 11 is subjected to plasma treatment. In the fourth step, an external electrode paste is attached to a part of the surface of the ceramic green body 11 after the third step. In the fifth step, the ceramic green body 11 after the fourth step is heat-treated to form the external electrode.

[0035] After the inventors conducted in-depth research to solve the above-mentioned problems, they found that the shape of the external electrode can be controlled by performing a specific treatment on the ceramic green body, and thus the present disclosure was completed. According to the manufacturing method of the multilayer ceramic component of the present embodiment, by including the first to fifth steps, it is possible to form the external electrodes 14 with the crescent shape suppressed in the multilayer ceramic component 1.

[0036] The reason why the manufacturing method of the multilayer ceramic component according to the present embodiment achieves the above effects by having the above configuration is considered, for example, that by performing plasma treatment on the surface of the ceramic green body 11 or the insulating layer 13 in the third step, the contact angle can be changed or increased, and thereby, wetting spread of the external electrode paste can be suppressed.

[0037] In the technique of using a release agent in the above Patent Document 1, there is a step of immersing in a liquid, so that not only a drying step becomes necessary, but also since the release agent has adhesiveness, the green body materials are likely to adhere to each other. Therefore, there is a problem that countermeasures etc. are required and the manufacturing process becomes complicated. In addition, even after firing, residues of the release agent sometimes remain, which may affect the characteristics of the manufactured multilayer ceramic component. Further, the technique of Patent Document 1 can make the interval between the side ends in a pair of external electrodes shorter than the interval between the central portions.

[0038] In contrast, in the manufacturing method of the multilayer ceramic component according to the present embodiment, steps such as plasma treatment are dry, and countermeasures against adhesion of the green body materials etc. are not required. Therefore, the manufacturing process can be made simple. In addition, the change in the surface of the green body material caused by plasma treatment disappears during firing, and even if it remains, it does not affect the characteristics of the manufactured multilayer ceramic component. Further, by adjusting conditions such as plasma treatment and firing, an effect of making the plan view shape of the external electrode close to a rectangular shape etc. can be obtained.

[0039] 2. Details

[0040] <Manufacturing Method of Multilayer Ceramic Component>

[0041] The manufacturing method of the multilayer ceramic component according to the present embodiment (hereinafter, also referred to as manufacturing method (I)) includes a first step, a second step, a third step, a fourth step, and a fifth step.

[0042] Manufacturing method (I) may further include a step of forming an insulating layer 13 on the surface of the ceramic green body 11 after the second step and before the third step (hereinafter, also referred to as an insulating layer forming step). When manufacturing method (I) includes the insulating layer forming step, in the third step, plasma treatment is performed on the surface of the insulating layer 13. When the insulating layer 13 having higher hydrophilicity on the surface than the ceramic green body 11 is provided, the advantages of using manufacturing method (I) are great.

[0043] In addition, the manufacturing method of the present embodiment may further include a step of forming a plated electrode so as to cover the external electrode 14 after the fifth step (hereinafter, also referred to as a plated electrode forming step).

[0044] Hereinafter, taking the case where the stacked ceramic component 1 is the stacked varistor 1 as an example, each process will be described.

[0045] [First Process]

[0046] In the first process, a laminate obtained by laminating a plurality of green ceramic sheets and a plurality of internal electrode paste layers is prepared.

[0047] The green ceramic sheet contains, for example, a ceramic component, a binder component, etc. The ceramic component usually contains at least zinc oxide (ZnO), and may also contain Pr6O 11 , Co2O3, CaO, Bi2O3, etc. As the binder component, for example, polyvinyl alcohol, polyvinyl butyral, cellulose ether, etc. can be cited.

[0048] The green ceramic sheet can be produced, for example, by preparing a slurry containing a powder of the ceramic component and organic components such as a binder component and a solvent, and forming the slurry using a coater or the like. The thickness of the green ceramic sheet is, for example, 20 μm or more and 50 μm or less.

[0049] The internal electrode paste layer contains, for example, metal powder. As the metal powder, for example, Pd powder, PdAg powder, etc. can be cited.

[0050] A laminate L is obtained by laminating a plurality of green ceramic sheets and a plurality of internal electrode paste layers in the third direction (Z direction).

[0051] [Second Process]

[0052] In the second process, the laminate L is fired to form the ceramic green body 11. Specifically, the laminate L is cut in the first direction (X direction) and the second direction (Y direction) to obtain a plurality of green bodies (hereinafter, also referred to as green body G) in which a part of the internal electrode paste layer is exposed on the exposed surface, and then the green body G is fired to form a plurality of ceramic green bodies 11. The shape of the green body G is usually a rectangular parallelepiped. The corners of the green body G may have rounded corners.

[0053] The firing of the laminate L is performed, for example, by heating the green body G. As the heating temperature, for example, it is 1300 °C or lower. As the heating atmosphere, for example, it can be cited in an air atmosphere, an inert gas atmosphere, etc. Through this firing, the binder component and the like contained in the green body G are thermally decomposed, and then the ceramic material is sintered to obtain a plurality of ceramic green bodies 11.

[0054] The ceramic green body 11 obtained through the second process includes a plurality of internal electrodes 12 inside.

[0055] [Insulating Layer Forming Process]

[0056] In the insulating layer formation process, an insulating layer 13 is formed on the surface of the ceramic green body 11 after the second process. For example, after attaching a precursor solution containing a glass component to the surface of the ceramic green body 11 obtained through the second process, heat treatment is performed, thereby forming the insulating layer 13 on the surface of the ceramic green body 11.

[0057] The "glass component" refers to an amorphous substance, meaning a substance having a softening point. The "softening point" means the temperature at which the glass component starts to deform due to temperature increase. As the glass component, for example, borosilicate zinc acid glass, etc. can be cited. In addition to the glass component, the precursor solution can also contain, for example, binder components such as cellulose ether, and organic components such as solvents. The softening point of the glass component is, for example, 300 °C or higher and 500 °C or lower.

[0058] The insulating layer 13 can be formed on a part of the surface of the ceramic green body 11 or on the entire surface of the ceramic green body 11.

[0059] [Third Process]

[0060] In the third process, plasma treatment is performed on the surface of the ceramic green body 11. In the case where the insulating layer formation process is performed after the second process, in the third process, plasma treatment is performed on the surface of the insulating layer 13.

[0061] For example, a plasma treatment device or the like can be used to perform plasma treatment. The plasma can be atmospheric pressure plasma or vacuum plasma.

[0062] As the gas used for plasma treatment, for example, hydrocarbons, fluorocarbons, fluorine, oxygen, air, hydrogen, inert gases, etc. can be cited.

[0063] As the hydrocarbon, for example, methane, etc. can be cited.

[0064] As the fluorocarbon, for example, it is C n F m (n and m are natural numbers), etc., and CF4, C2F4, C3F6, C4F8, C4F 10 etc. can be cited.

[0065] As the inert gas, argon, nitrogen, etc. can be cited.

[0066] As the gas used for plasma treatment, from the viewpoint of being able to more simply increase the contact angle of the surface of the ceramic green body 11 or the insulating layer 13, fluorocarbons are preferred, and C4F8 is more preferred.

[0067] As the time of plasma treatment, for example, it is 5 seconds or more, preferably 10 seconds or more, more preferably 20 seconds or more, further preferably 45 seconds or more, and particularly preferably 75 seconds or more. The upper limit of the time of plasma treatment is not particularly limited, but for example, it is 5 minutes or less, preferably 2 minutes or less.

[0068] Plasma treatment can be performed on a part of the surface of the ceramic green body 11 or the insulating layer 13, or on the entire surface of the ceramic green body 11 or the insulating layer 13.

[0069] Before plasma treatment, a pre-cleaning treatment can also be performed on the surface of the ceramic green body 11 or the insulating layer 13. For example, this pre-cleaning treatment can be performed by argon plasma treatment for about 30 seconds.

[0070] Preferably, the surface of the ceramic green body 11 or the insulating layer 13 after the third process is hydrophobized by plasma treatment. "Hydrophobized" means that the contact angle of water on the surface of the ceramic green body 11 or the insulating layer 13 after plasma treatment (hereinafter also referred to as the post-plasma treatment contact angle) is increased compared to before plasma treatment (hereinafter also referred to as the pre-plasma treatment contact angle).

[0071] The increase value of the contact angle before and after plasma treatment (= post-plasma treatment contact angle - pre-plasma treatment contact angle) is, for example, 60° or more, preferably 65° or more, more preferably 70° or more, further preferably 75° or more. The upper limit of the increase value of the contact angle is not particularly limited, but for example, it is 90° or less.

[0072] The post-plasma treatment contact angle is, for example, 100° or more, preferably 105° or more, more preferably 110° or more, further preferably 113° or more, and particularly preferably 115° or more. The upper limit of the post-plasma treatment contact angle is not particularly limited, but for example, it is 130° or less, preferably 120° or less.

[0073] [Fourth Process]

[0074] In the fourth process, an external electrode paste is attached to a part of the surface of the ceramic green body 11 after the third process. In the case where an insulating layer forming process is performed after the second process, in the fourth process, an external electrode paste is attached to a part of the surface of the insulating layer 13 after the third process. According to the manufacturing method (I), the wetting spread of the external electrode paste can be suppressed in the fourth process.

[0075] The external electrode paste contains metal powder. As such metal powder, for example, Ag powder, AgPd powder, AgPt powder, etc. can be cited. The external electrode paste can also contain, for example, glass components such as Bi2O3, SiO2, B2O3, resin components, solvents, etc.

[0076] As a method for attaching the external electrode paste, for example, the dip coating method in which the ceramic green body 11 or the insulating layer 13 is immersed in the external electrode paste in a container, the roll transfer method in which the external electrode paste attached to the convex plate is pressed against the ceramic green body 11 or the insulating layer 13 for coating, etc. can be cited.

[0077] The part where the external electrode paste is attached in the ceramic green body 11 or the insulating layer 13 is not particularly limited, and it can be on the end faces S11, S12, it can also be on the side faces S21, S22, and it can also be on the main faces S31, S32.

[0078] In this way, the manufacturing method (I) can be applied to the formation of the end face external electrodes 14A, 14B, and can also be applied to the formation of the side face external electrodes 14C, 14D.

[0079] [Step 5]

[0080] In the 5th step, the ceramic green body 11 after the 4th step is heat-treated to form the external electrode 14. In the case where the insulating layer formation step is performed after the 2nd step, in the 5th step, the insulating layer 13 after the 4th step is heat-treated to form the external electrode 14. According to the manufacturing method (I), by performing heat treatment in the 5th step, the fluorine atoms combined or attached to the ceramic green body 11 or the insulating layer 13 can be removed.

[0081] Specifically, heat treatment is performed by heating the external electrode paste. As the temperature of this heating, for example, it is 700°C or higher and 800°C or lower.

[0082] Preferably, on the surface layer of the part of the surface of the ceramic green body 11 after the 5th step where the external electrode 14 is not formed, there are no fluorine atoms. In the case where the insulating layer formation step is performed after the 2nd step, preferably, on the surface layer of the surface of the insulating layer 13 after the 5th step when the external electrode 14 is not formed, there are no fluorine atoms. By having no fluorine atoms in the surface layer of the ceramic green body 11 or the insulating layer 13, in the subsequent plating electrode formation step, there are no adverse situations caused by the buoyancy of the object to be plated, etc., and the plating operation can be performed well.

[0083] The so-called "fluorine atoms do not exist on the surface layer" means that it includes the meaning that fluorine atoms substantially do not exist. The "surface layer" refers to the region within usually 10 nm from the surface, and this distance corresponds to the detection depth of X-ray Fluorescence (XRF) analysis. "Fluorine atoms substantially do not exist" means that the concentration of fluorine atoms is less than the detection lower limit of XRF analysis.

[0084] Figure 3 This is a diagram showing the crescent shape of the external electrodes 14 (14A, 14B) formed on a part of the main surface S31 of the ceramic green body 11 in the multilayer ceramic component 1. In Figure 3 it, L1 is the maximum length in the second direction (Y direction) of the external electrode 14B having a crescent shape (the length in the second direction (Y direction) at the central part in the first direction (X direction) of the external electrode 14B), and L1s is the minimum length in the second direction (Y direction) of the external electrode 14B (the length in the second direction (Y direction) at both ends in the first direction (X direction) of the external electrode 14B).

[0085] In the external electrode 14 in the multilayer ceramic component 1 after the fifth process, the value of (L1 - L1s) (hereinafter, also referred to as the crescent difference M) is a numerical value representing the degree of the crescent shape of the external electrode 14.

[0086] Regarding the measured values of the crescent difference M (arithmetic average of any 10 points) and the contact angle N of water on the surface in the multilayer ceramic component 1 after the fifth process obtained by the manufacturing method (I), without plasma treatment, it is (M: 0.060, N: 38°). In contrast, in the case of plasma treatment in the presence of carbon fluoride, when the plasma treatment time is 15 seconds, it is (M: 0.021, N: 108°), when the plasma treatment time is 30 seconds, it is (M: 0.026, N: 108°), when the plasma treatment time is 60 seconds, it is (M: 0.021, N: 115°), and when the plasma treatment time is 90 seconds, it is (M: 0.019, 118°).

[0087] In this way, according to the manufacturing method (I), the crescent shape of the external electrodes 14 (14A, 14B, 14C, 14D) of the multilayer ceramic component 1 can be suppressed. As a result, the control of the coating size of the external electrode 14 becomes easy.

[0088] In the manufacturing method (I), the fourth process and the fifth process may be repeated to form a secondary external electrode in addition to the primary external electrode as the external electrode 14.

[0089] [Plating electrode formation process]

[0090] In the plating electrode forming step, a plating electrode is formed so as to cover the external electrode 14.

[0091] For example, the plating electrode can be formed by performing electrolytic plating or by sequentially performing Ni plating and Sn plating.

[0092] As described above, by the manufacturing method (I), it is possible to manufacture the laminated varistor 1 in which the ceramic green body 11 contains zinc oxide as a main component and the external electrode 14 with a suppressed crescent shape. The manufacturing method (I) can also be suitably applied to the laminated varistor 1 that sometimes has an insulating layer 13 with higher hydrophilicity on the surface.

[0093] In addition, by the manufacturing method (I), similarly to the above-described laminated varistor, it is possible to manufacture a laminated thermistor, a laminated ceramic capacitor, etc. having an external electrode 14 with a suppressed crescent shape.

[0094] Regarding the laminated thermistor, the ceramic green body 11 contains, for example, Mn, Co, Fe, Al, Cu, etc., the internal electrode paste layer contains, for example, Pd, etc., and the external electrode paste contains, for example, Cu, etc.

[0095] Regarding the laminated ceramic capacitor, the ceramic green body 11 contains, for example, BaTiO3, CaZrO3, CaTiO3, SrTiO3, etc. as main components, contains MgO, Dy2O3, SiO2, MnO2, etc. as sub-components, the internal electrode paste layer contains, for example, Pt, Pd, Ag, Au, Ni, Cu, Sn, etc., and the external electrode paste contains, for example, Cu, Ni, Al, Zn, Cu-Ni, etc.

[0096] (Summary)

[0097] As is clear from the above-described embodiments, the present disclosure includes the following aspects. Hereinafter, parentheses are attached to the reference numerals only for clarifying the correspondence with the embodiments.

[0098] The manufacturing method of the laminated ceramic component according to the first aspect includes a first step, a second step, a third step, a fourth step, and a fifth step. In the first step, a laminate (L) obtained by laminating a plurality of ceramic green sheets and a plurality of internal electrode paste layers is prepared. In the second step, the laminate (L) is fired to form a ceramic green body (11). In the third step, the surface of the ceramic green body (11) is subjected to plasma treatment. In the fourth step, an external electrode paste is attached to a part of the surface of the ceramic green body (11) after the third step. In the fifth step, the ceramic green body (11) after the fourth step is heat-treated to form an external electrode (14).

[0099] According to the first method, it is possible to suppress the wetting spread of the external electrode paste, and thus a laminated ceramic component (1) having an external electrode (14) with a suppressed crescent shape can be obtained. As a result, the control of the coating size becomes easy.

[0100] In the method for manufacturing a laminated ceramic component according to the second method, in the first method, the plasma treatment in the third process is performed in the presence of carbon fluoride.

[0101] According to the second method, by using the plasma treatment with carbon fluoride, it is possible to further increase the contact angle of the surface after the plasma treatment and further suppress the crescent shape of the external electrode (14).

[0102] In the method for manufacturing a laminated ceramic component according to the third method, in the first or second method, the surface of the ceramic green body (11) after the third process is hydrophobized by plasma treatment.

[0103] According to the third method, since the surface is hydrophobized by plasma treatment, it is possible to further suppress the crescent shape of the external electrode (14).

[0104] In the method for manufacturing a laminated ceramic component according to the fourth method, in the second or third method, in the surface layer of the part of the surface of the ceramic green body (11) where the external electrode (14) is not formed after the fifth process, fluorine atoms do not exist.

[0105] According to the fourth method, since fluorine atoms do not exist in the surface layer, in the plating electrode formation process, there are no adverse conditions caused by the buoyancy of the object to be plated, etc., and the plating operation can be performed well.

[0106] In the method for manufacturing a laminated ceramic component according to the fifth method, in any one of the first to fourth methods, after the second process and before the third process, there is also a process of forming an insulating layer (13) on the surface of the ceramic green body after the second process, and in the third process, the surface of the insulating layer (13) is subjected to plasma treatment.

[0107] According to the fifth method, in the case of having an insulating layer (13) with a higher surface hydrophilicity than the ceramic green body (11), the advantages of the method for manufacturing the laminated ceramic component (1) of the present disclosure are great.

[0108] In the method for manufacturing a laminated ceramic component according to the sixth method, in any one of the first to fifth methods, the laminated ceramic component (1) is a laminated varistor (1) in which the ceramic green body (11) contains zinc oxide as a main component.

[0109] According to the sixth method, the method for manufacturing the laminated ceramic component (1) of the present disclosure can also be suitably used for a laminated varistor (1) that sometimes has an insulating layer (13) with a higher surface hydrophilicity.

Claims

1. A method for manufacturing a stacked ceramic component, comprising: a first step of preparing a laminate obtained by laminating a plurality of green ceramic sheets and a plurality of internal electrode pastes; a second step of firing the laminate to form a ceramic body; a third step of subjecting the surface of the ceramic body to plasma treatment; a fourth step of causing an external electrode paste to adhere to a part of the surface of the ceramic body after the third step; and a fifth step of subjecting the ceramic body after the fourth step to heat treatment to form an external electrode.

2. The method for manufacturing a stacked ceramic component according to claim 1, wherein the plasma treatment in the third step is performed in the presence of carbon fluoride.

3. The method for manufacturing a stacked ceramic component according to claim 1, wherein the surface of the ceramic body after the third step is hydrophobized by the plasma treatment.

4. The method for manufacturing a stacked ceramic component according to claim 2, wherein fluorine atoms do not exist in the surface layer of the part of the surface of the ceramic body after the fifth step where the external electrode is not formed.

5. The method for manufacturing a stacked ceramic component according to claim 1, wherein after the second step and before the third step, there is further a step of forming an insulating layer on the surface of the ceramic body after the second step, and in the third step, the surface of the insulating layer is subjected to the plasma treatment.

6. The method for manufacturing a stacked ceramic component according to claim 5, wherein the stacked ceramic component is a stacked varistor in which the ceramic body contains zinc oxide as a main component.

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