Manufacturing method for multilayer ceramic electronic components

Abstract

To provide a technique capable of forming a side margin portion of uniform thickness on the side surface of a laminate by a punching method.SOLUTION: In a manufacturing method for a multilayer ceramic electronic component, a first side margin portion is formed on a first side surface of a plurality of laminates arranged on a first adhesive sheet holding a second side surface, which has the first and second side surfaces from which a plurality of internal electrodes are exposed. The plurality of laminates with the first side margin portions formed thereon are transferred from the first adhesive sheet to a second adhesive sheet. A series of second side margin sheets are placed on the second side surface of the plurality of laminates transferred to the second adhesive sheet. While a pair of high-rigidity surfaces are in contact with the second adhesive sheet and the second side margin sheet, pressing force is applied to the pair of high-rigidity surfaces via an elastic member, and therefore, the second side margin sheet is crimped to the second side surface of the plurality of laminates. The second side margin portion is formed by punching the crimped second side margin sheet on the second side surfaces of the plurality of laminates.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a multilayer ceramic electronic component in which a side margin portion is attached later. [Background technology]

[0002] There is a known technique for adding side margins during the manufacturing process of a multilayer ceramic capacitor (see, for example, Patent Document 1). This technique is advantageous for miniaturizing multilayer ceramic capacitors and increasing their capacitance because the side surfaces of the laminate where the internal electrodes are exposed can be reliably protected even by thin side margins.

[0003] As an example, in the method of manufacturing a multilayer ceramic capacitor described in Patent Document 1, a laminate sheet in which ceramic sheets on which internal electrodes are printed are laminated is cut to produce a plurality of laminates whose cut surfaces expose the internal electrodes as side surfaces.Then, the ceramic sheet is punched out at the side surfaces of the laminates to form side margins on the side surfaces of the laminates.

[0004] Furthermore, in the technology described in Patent Document 1, the side margin portion punched out from the side surface of the laminate is pressed into a pressure-bonding elastic body while being heated, thereby thermocompression bonding the side surface of the laminate. This allows the side margin portion formed by punching out the ceramic sheet to have high adhesion to the side surface of the laminate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-209539 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the above-mentioned technique of crimping the side margins using a crimping elastic, the pressing force applied from the crimping elastic tends to concentrate on the ridges along the contour of the side margins, which causes the side margins to deform significantly after crimping, making the thickness of the side margins uneven.

[0007] In view of the above circumstances, an object of the present invention is to provide a technique capable of forming a side margin portion of uniform thickness on the side surface of a laminate by a punching method. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, in one embodiment of the present invention, a method for manufacturing a multilayer ceramic electronic component includes a plurality of ceramic layers stacked in a first axial direction, a plurality of internal electrodes located between the plurality of ceramic layers, and first and second side surfaces facing a second axial direction perpendicular to the first axis and exposing the plurality of internal electrodes, and a first side margin portion is formed on the first side surface of a plurality of laminates arranged on a first adhesive sheet that holds the second side surface. The plurality of laminates having the first side margin portions formed thereon are transferred from the first adhesive sheet to a second adhesive sheet. A series of second side margin sheets are disposed on the second sides of the plurality of laminates transferred to the second adhesive sheet. With a pair of high-rigidity surfaces opposing each other in the second axial direction in contact with the second adhesive sheet and the second side margin sheet, a pressing force is applied to the pair of high-rigidity surfaces via an elastic member that is elastically deformable along the second axis, thereby pressing the second side margin sheet against the second side surface of the multiple laminates. The second side margin portion is formed by punching out the compressed second side margin sheet at the second side surface of the plurality of laminates.

[0009] In this configuration, by pressing the second side margin sheet against the second side surfaces of the multiple laminates while it is sandwiched between a pair of high-rigidity surfaces, a second side margin portion that has high adhesion to the second side surfaces of the multiple laminates can be formed without compromising the uniformity of the thickness of the first and second side margin portions.

[0010] The second side margin sheet may be heated when the second side margin sheet is pressure-bonded. In this configuration, a second side margin portion can be formed that has even higher adhesiveness to the second side surfaces of the multiple laminates.

[0011] When the second side margin sheet is pressure-bonded, the second side margin sheet may be compressively deformed. In this case, the second side margin sheet before pressure-bonding may be thicker than the first side margin portion. In these configurations, even if there is variation in the height of the second side surfaces of the multiple laminates, the second side margin sheet can be pressed and bonded well to the second side surfaces of the multiple laminates. Effect of the Invention

[0012] As described above, according to the present invention, a technique can be provided that makes it possible to form side margin portions of uniform thickness on the side surfaces of a laminate by punching. [Brief description of the drawings]

[0013] [Figure 1] 1 is a perspective view of a multilayer ceramic capacitor according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view of the multilayer ceramic capacitor taken along line AA' in FIG. [Diagram 3] 2 is a cross-sectional view of the multilayer ceramic capacitor taken along line BB' in FIG. [Figure 4] 4 is a flowchart showing a method for manufacturing the multilayer ceramic capacitor. [Diagram 5]FIG. 2 is a plan view of a ceramic sheet prepared in a ceramic sheet preparing step of the manufacturing method. [Figure 6] FIG. 2 is a perspective view showing a lamination step of the manufacturing method. [Figure 7] FIG. 4 is a plan view showing a cutting step in the manufacturing method. [Figure 8] FIG. 4 is a partial cross-sectional view showing the cutting step. [Figure 9] FIG. 2 is a perspective view of an unfired ceramic body obtained in a side margin portion forming step of the above manufacturing method. [Figure 10] 6 is a flowchart showing a method of forming a side margin portion in the manufacturing method. [Figure 11] FIG. 4 is a partial cross-sectional view showing a first pressure bonding step of the forming method. [Figure 12] FIG. 4 is a partial cross-sectional view showing a first punching step of the forming method. [Figure 13] FIG. 4 is a partial cross-sectional view showing a second pressure bonding step of the forming method. [Figure 14] FIG. 4 is a partial cross-sectional view showing a comparative example of the second pressure-bonding step. [Figure 15] FIG. 4 is a partial cross-sectional view showing another configuration of the second pressure-bonding step. [Figure 16] FIG. 4 is a partial cross-sectional view showing another configuration of the second pressure-bonding step. [Figure 17] FIG. 4 is a partial cross-sectional view showing another configuration of the second pressure-bonding step. [Figure 18] FIG. 4 is a partial cross-sectional view showing a second punching step of the forming method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] <Multilayer ceramic capacitor 10> Hereinafter, a multilayer ceramic capacitor 10 according to one embodiment of the present invention will be described with reference to the drawings. In addition, in Figures 1 to 9, an X-axis, a Y-axis, and a Z-axis that are mutually orthogonal are appropriately shown. The X-axis, the Y-axis, and the Z-axis define a fixed coordinate system that is fixed with respect to the multilayer ceramic capacitor 10.

[0015] [Configuration of multilayer ceramic capacitor 10] 1 to 3 are diagrams showing a multilayer ceramic capacitor 10 according to an embodiment of the present invention. Fig. 1 is a perspective view of the multilayer ceramic capacitor 10. Fig. 2 is a cross-sectional view of the multilayer ceramic capacitor 10 taken along line A-A' in Fig. 1. Fig. 3 is a cross-sectional view of the multilayer ceramic capacitor 10 taken along line B-B' in Fig. 1.

[0016] The multilayer ceramic capacitor 10 includes a ceramic body 11, a first external electrode 14, and a second external electrode 15. The ceramic body 11 is configured as a hexahedron having first and second end faces perpendicular to the X-axis, first and second side faces perpendicular to the Y-axis, and first and second main faces perpendicular to the Z-axis.

[0017] The external electrodes 14, 15 cover both end faces of the ceramic body 11 and face each other in the X-axis direction with the ceramic body 11 in between. The external electrodes 14, 15 extend from each end face of the ceramic body 11 to the main surface and side surfaces. As a result, the external electrodes 14, 15 have a U-shape in both a cross section parallel to the XZ plane and a cross section parallel to the XY plane.

[0018] The shape of the external electrodes 14, 15 is not limited to that shown in Fig. 1. For example, the external electrodes 14, 15 may extend from both end faces of the ceramic body 11 to only one of the main surfaces, and may have an L-shaped cross section parallel to the XZ plane. Furthermore, the external electrodes 14, 15 may not extend to any of the main surfaces or side surfaces.

[0019] The external electrodes 14, 15 are made of a good electrical conductor. Examples of the good electrical conductor that forms the external electrodes 14, 15 include metals or alloys containing, as a main component, copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), silver (Ag), gold (Au), etc.

[0020] The ceramic body 11 is made of dielectric ceramics and has a laminate 16 and first and second side margin portions 17a, 17b. The laminate 16 has first and second side surfaces S1, S2 facing the Y-axis direction. The laminate 16 also has first and second end faces facing the X-axis direction and first and second main surfaces facing the Z-axis direction.

[0021] The laminate 16 has a configuration in which a plurality of flat ceramic layers extending along the XY plane are stacked in the Z-axis direction. The laminate 16 has a capacitance forming portion 18 and a cover portion 19. The cover portion 19 covers the capacitance forming portion 18 from above and below in the Z-axis direction, and constitutes first and second main surfaces of the laminate 16.

[0022] The capacitance forming portion 18 is disposed between a plurality of ceramic layers, and has a plurality of sheet-like first and second internal electrodes 12, 13 extending along the XY plane. The internal electrodes 12, 13 are alternately disposed along the Z-axis direction. In other words, the internal electrodes 12, 13 face each other in the Z-axis direction with the ceramic layers sandwiched therebetween.

[0023] The first internal electrode 12 is extended to an end face covered by the first external electrode 14. On the other hand, the second internal electrode 13 is extended to an end face covered by the second external electrode 15. As a result, the first internal electrode 12 is connected only to the first external electrode 14, and the second internal electrode 13 is connected only to the second external electrode 15.

[0024] The internal electrodes 12, 13 are formed across the entire width of the capacitance forming portion 18 in the Y-axis direction, and are exposed on the side surfaces S1, S2 of the laminate 16. The first side margin portion 17a covers the first side surface S1 of the laminate 16, and the second side margin portion 17b covers the second side surface S2 of the laminate 16. This ensures insulation between the internal electrodes 12, 13 on both side surfaces S1, S2 of the laminate 16.

[0025] With this configuration, in the multilayer ceramic capacitor 10, when a voltage is applied between the first external electrode 14 and the second external electrode 15, the voltage is applied to the multiple ceramic layers between the first internal electrode 12 and the second internal electrode 13. As a result, a charge corresponding to the voltage between the first external electrode 14 and the second external electrode 15 is stored in the multilayer ceramic capacitor 10.

[0026] In the ceramic body 11, a dielectric ceramic with a high dielectric constant is used to increase the capacitance of each ceramic layer between the internal electrodes 12 and 13. An example of a dielectric ceramic with a high dielectric constant is a material with a perovskite structure containing barium (Ba) and titanium (Ti), such as barium titanate (BaTiO3).

[0027] The ceramic layer may be composed of compositions such as strontium titanate (SrTiO3), calcium titanate (CaTiO3), magnesium titanate (MgTiO3), calcium zirconate (CaZrO3), calcium zirconate titanate (Ca(Zr,Ti)O3), barium zirconate (BaZrO3), and titanium oxide (TiO2).

[0028] The internal electrodes 12 and 13 are made of a good electrical conductor. Typical examples of good electrical conductors that form the internal electrodes 12 and 13 include nickel (Ni), as well as metals or alloys mainly composed of copper (Cu), palladium (Pd), platinum (Pt), silver (Ag), gold (Au), etc.

[0029] [Method of manufacturing multilayer ceramic capacitor 10] Fig. 4 is a flowchart showing a method for manufacturing the multilayer ceramic capacitor 10 according to this embodiment. Figs. 5 to 9 are views showing the manufacturing process of the multilayer ceramic capacitor 10. The method for manufacturing the multilayer ceramic capacitor 10 will be described below along Fig. 4 with appropriate reference to Figs. 5 to 9.

[0030] (Step S01: Prepare ceramic sheet) In step S01, a first ceramic sheet 101 and a second ceramic sheet 102 for forming the capacitance forming portion 18, and a third ceramic sheet 103 for forming the cover portion 19 are prepared. The ceramic sheets 101, 102, and 103 are configured as unfired dielectric green sheets whose main component is dielectric ceramics.

[0031] The ceramic sheets 101, 102, and 103 are formed into a sheet shape using, for example, a roll coater or a doctor blade. The thickness of the ceramic sheets 101 and 102 is adjusted according to the thickness of the ceramic layer in the capacitance forming portion 18 after firing. The thickness of the third ceramic sheet 103 can be adjusted as appropriate.

[0032] Fig. 5 is a plan view of the ceramic sheets 101, 102, and 103. At this stage, the ceramic sheets 101, 102, and 103 are configured as large sheets that have not been divided into individual pieces. Fig. 5 shows cutting lines Lx and Ly for dividing into individual multilayer ceramic capacitors 10. The cutting line Lx is parallel to the X-axis, and the cutting line Ly is parallel to the Y-axis.

[0033] 5, an unsintered first internal electrode 112 corresponding to the first internal electrode 12 is formed on the first ceramic sheet 101, and an unsintered second internal electrode 113 corresponding to the second internal electrode 13 is formed on the second ceramic sheet 102. No internal electrode is formed on the third ceramic sheet 103 corresponding to the cover portion 19.

[0034] The internal electrodes 112, 113 can be formed by applying any conductive paste to the ceramic sheets 101, 102. The method for applying the conductive paste can be selected from among known techniques. For example, the conductive paste can be applied by screen printing or gravure printing.

[0035] Gaps in the X-axis direction along the cutting lines Ly are formed in the internal electrodes 112, 113 for every other cutting line Ly. The gaps in the first internal electrode 112 and the gaps in the second internal electrode 113 are arranged alternately in the X-axis direction. In other words, the cutting lines Ly passing through the gaps in the first internal electrode 112 and the cutting lines Ly passing through the gaps in the second internal electrode 113 are arranged alternately.

[0036] (Step S02: Lamination) In step S02, the ceramic sheets 101, 102, and 103 prepared in step S01 are laminated as shown in Fig. 6 to produce a laminated sheet 104. In the laminated sheet 104, the first ceramic sheet 101 and the second ceramic sheet 102 corresponding to the capacitance forming portion 18 are laminated alternately in the Z-axis direction.

[0037] In the laminated sheet 104, third ceramic sheets 103 corresponding to the cover portion 19 are laminated on the upper and lower surfaces in the Z-axis direction of the alternately laminated ceramic sheets 101 and 102. In the example shown in Fig. 6, three third ceramic sheets 103 are laminated, but the number of third ceramic sheets 103 can be changed as appropriate.

[0038] The laminated sheet 104 is integrated by pressing the ceramic sheets 101, 102, and 103 together. For example, hydrostatic pressure or uniaxial pressure is preferably used for pressing the ceramic sheets 101, 102, and 103 together. This makes it possible to increase the density of the laminated sheet 104.

[0039] (Step S03: Disconnect) In step S03, the laminate sheet 104 obtained in step S02 is cut along cutting lines Lx and Ly to produce an unfired laminate 116. The laminate 116 corresponds to the fired laminate 16. For example, a press blade or a rotary blade can be used to cut the laminate sheet 104.

[0040] 7 and 8 are schematic diagrams for explaining an example of step S03. Fig. 7 is a plan view of the laminated sheet 104. Fig. 8 is a cross-sectional view along the YZ plane of the laminated sheet 104. The laminated sheet 104 is cut by the push cutter blade BL along the cutting lines Lx and Ly while being held by an adhesive cut sheet C such as a foamed release sheet.

[0041] First, as shown in Fig. 8(A), the push-cutting blade BL is disposed above the laminated sheet 104 in the Z-axis direction, with the tip facing the laminated sheet 104 below in the Z-axis direction. Next, as shown in Fig. 8(B), the push-cutting blade BL is moved downward in the Z-axis direction until it reaches the cut sheet C, and penetrates the laminated sheet 104.

[0042] 8(C), the cutting blade BL is moved upward in the Z-axis direction to pull it out from the laminated sheet 104. As a result, the laminated sheet 104 is cut in the X-axis and Y-axis directions to form a laminate 116 having first and second side surfaces S1, S2 on which the internal electrodes 112, 113 are exposed in the Y-axis direction.

[0043] (Step S04: Forming side margins) In step S04, an unsintered first side margin 117a is provided on the first side surface S1 of the laminate 116 obtained in step S03, and an unsintered second side margin 117b is provided on the second side surface S2 of the laminate 116. This results in an unsintered ceramic body 111 in which the side surfaces S1 and S2, on which the internal electrodes 112 and 113 are exposed, are covered by the side margins 117a and 117b, as shown in Fig. 9.

[0044] The side margin portions 117a, 117b formed by the method according to this embodiment have high adhesion to the side surfaces S1, S2 of the laminate 116 without impairing the uniformity of the thickness. This makes it possible to achieve high reliability and yield of the multilayer ceramic capacitor 10. The method of forming the side margin portions 117a, 117b in step S04 will be described in detail later.

[0045] (Step S05: Firing) In step S05, the ceramic body 111 obtained in step S04 and shown in Fig. 9 is fired to produce the ceramic body 11 of the multilayer ceramic capacitor 10 shown in Figs. 1 to 3. That is, in step S05, the laminate 116 becomes the laminate 16, and the side margin portions 117a, 117b become the side margin portions 17a, 17b.

[0046] The firing temperature in step S05 can be determined based on the sintering temperature of the ceramic body 111. For example, when a barium titanate (BaTiO3)-based material is used, the firing temperature can be about 1000 to 1300° C. Furthermore, the firing can be performed, for example, in a reducing atmosphere or a low oxygen partial pressure atmosphere.

[0047] (Step S06: Forming external electrodes) In step S06, external electrodes 14, 15 are formed on both ends in the X-axis direction of the ceramic body 11 obtained in step S05, thereby producing the multilayer ceramic capacitor 10 shown in Figures 1 to 3. The method for forming the external electrodes 14, 15 in step S06 can be arbitrarily selected from known methods.

[0048] This completes the multilayer ceramic capacitor 10. In this manufacturing method, side margin portions 117a, 117b are formed on the side surfaces S1, S2 of the laminate 116 where the internal electrodes 112, 113 are exposed, so that the positions of the ends in the Y-axis direction of the multiple internal electrodes 12, 13 in the ceramic body 11 are aligned to within 0.5 μm.

[0049] <Method of forming side margin portions 117a, 117b> Fig. 10 is a flow chart showing a method for forming the side margins 117a and 117b in step S04. Figs. 11 to 18 are diagrams for explaining the method for forming the side margins 117a and 117b. The method for forming the side margins 117a and 117b will be explained below along Fig. 10 with appropriate reference to Figs. 11 to 18.

[0050] 11 to 18 show x-axis, y-axis, and z-axis which are mutually orthogonal. Unlike the above-mentioned X-axis, Y-axis, and Z-axis, the x-axis, y-axis, and z-axis define a real space coordinate system fixed with respect to the real space. The x-axis and y-axis extend horizontally, that is, the xy plane is the horizontal plane. The z-axis extends vertically, up and down.

[0051] (Step S41: Changing the stack orientation) In step S41, the orientation of the multiple laminates 116 after step S03 is changed. That is, in the state immediately after step S03 shown in Fig. 8(C), the side surfaces S1, S2 of the adjacent laminates 116 are closely opposed to each other in the Y-axis direction, making it difficult to form the side margin portions 117 on the side surfaces S1, S1 of each laminate 116. For this reason, in step S41, the orientation of the side surfaces S1, S2 of the multiple laminates 116 is changed from the horizontal direction (y-axis direction) to the vertical direction (z-axis direction).

[0052] A known method such as a rolling method can be used to change the orientation of the side surfaces S1, S2 of the multiple laminates 116. In the rolling method, the laminates 116 are first attached from the cut sheet C to a first adhesive sheet F1 having extensibility, and the first adhesive sheet F1 is stretched to increase the spacing of the laminates 116 in the y-axis direction.

[0053] Then, the plurality of laminates 116 are rolled in the y-axis direction on the first adhesive sheet F1. At this time, all of the laminates 116 can be rolled together by using, for example, a rolling plate. This causes the laminates 116 to rotate 90°, so that the side surfaces S1 and S2 face upward and downward in the z-axis direction, respectively.

[0054] After step S41, in each of the multiple laminates 116, the second side surface S2 facing downward is held by the first adhesive sheet F1, and the first side surface S1 faces upward (see FIG. 11(A)). This makes it possible to form the first side margin portion 117a collectively on the first side surfaces S1 facing upward in all of the laminates 116.

[0055] (Step S42: First crimping) In step S42, a first side margin sheet 117s1 constituting the first side margin portion 117a is pressure-bonded to the first side surface S1 of the plurality of laminates 116 that were directed upward in step S41. Figures 11(A) to 11(C) are diagrams showing the process of pressure-bonding the first side margin sheet 117s1 in step S42.

[0056] The first side margin sheet 117s1 used in step S42 is configured as an unsintered dielectric green sheet. The configuration of the first side margin sheet 117s1 may be the same as or different from the configuration of the ceramic sheets 101, 102, and 103 prepared in step S01 for forming the laminate 116.

[0057] In step S42, a rigid plate P and an elastic plate Q extending along the xy plane are used. The upper and lower surfaces of the rigid plate P are configured as highly rigid surfaces p that maintain a planar shape even when pressed. The upper and lower surfaces of the elastic plate Q are configured as elastic surfaces q that are planar in a free state when not pressed, and elastically deform when pressed.

[0058] The rigid plate P is made of a material generally classified as a rigid body, such as stainless steel or aluminum. Therefore, minute elastic deformations, the effect of which on the planar shape can be ignored, may occur on the highly rigid surface p of the rigid plate P. The elastic plate Q is made of a material generally classified as an elastic body, such as various types of rubber.

[0059] 11(A), in step S42, a series of first side margin sheets 117s1 extending along the xy plane are arranged on the first side surfaces S1 of the multiple laminates 116 so as to collectively cover the multiple laminates 116. Then, the elastic surface q of the elastic plate Q and the high rigidity surface p of the rigid plate P are opposed to each other in the z-axis direction with the multiple laminates 116 and the first side margin sheet 117s1 in between.

[0060] Specifically, the elastic plate Q is disposed below the multiple laminates 116, and the elastic surface q holds the lower surface of the first adhesive sheet F1 on which the multiple laminates 116 are arranged. The rigid plate P is disposed above the multiple laminates 116, and the high rigidity surface p faces the first side margin sheet 117s1 disposed on the first side surface S1 of the multiple laminates 116.

[0061] 11(B), the rigid plate P is moved downward, and the first side margin sheet 117s1 is pressed downward by the high-rigidity surface p of the rigid plate P. As a result, the multiple laminates 116 pressed down together with the first side margin sheet 117s1 press the elastic surface q of the elastic plate Q via the first adhesive sheet F1, thereby compressing and deforming the elastic plate Q.

[0062] At this time, a pressing force according to the elastic force of the compressively deformed elastic plate Q is applied between the first side surface S1 of the multiple laminates 116 and the first side margin sheet 117s1. This allows the first side margin sheet 117s1 to be in close contact with the first side surface S1 of the multiple laminates 116.

[0063] In this embodiment, a pressing force is applied to the first side margin sheet 117s1 by the high-rigidity surface p of the rigid plate P, so that a uniform pressure is applied to the first side margin sheet 117s1 between the high-rigidity surface p of the rigid plate P and the first side surface S1 of the multiple laminates 116. This makes it possible to prevent local deformation of the first side margin sheet 117s1 on the first side surface S1 of the multiple laminates 116.

[0064] 11(A), the first side surfaces S1 of the laminates 116 are aligned on the same plane by sinking into the elastic surface q of the elastic plate Q of each laminate 116 in the state shown in FIG.

[0065] 11(C), the rigid plate P is moved upward. As a result, the high-rigidity surface p of the rigid plate P is separated from the first side margin sheet 117s1, and the pressing force applied from the high-rigidity surface p of the rigid plate P to the first side margin sheet 117s1 is released. Accordingly, the elastic surface q of the elastic plate Q returns to a flat shape.

[0066] In step S42, the first side margin sheet 117s1 is softened by heating, thereby further improving the adhesion to the first side surface S1 of the multiple laminates 116. In this embodiment, even with the first side margin sheet 117s1 softened in this manner, the effect of preventing local deformation on the first side surface S1 of the multiple laminates 116 can be effectively obtained.

[0067] (Step S43: First punching) In step S43, the first side margin sheet 117s1 pressure-bonded in step S42 is punched out by the first side surfaces S1 of the plurality of laminates 116. Figures 12(A) to 12(C) are diagrams showing the process of punching out the first side margin sheet 117s1 by the first side surfaces S1 of the plurality of laminates 116 in step S43.

[0068] In step S43, first, as shown in Fig. 12(A), the lower surface of the first adhesive sheet F1 is held by the high-rigidity surface p of the rigid plate P. In addition, a pressing member E extending along the xy plane is disposed above the first side margin sheet 117s1. It is preferable that the pressing member E is more flexible than the elastic plate Q. The pressing member E can be formed of, for example, various types of rubber or various types of elastomers.

[0069] 12(B), the pressing member E is moved downward until it contacts the first side margin sheet 117s1, and the first side margin sheet 117s1 is further pressed downward by the pressing member E. At this time, the positions of the multiple laminates 116 on the first adhesive sheet F1 held by the high rigidity surface p of the rigid plate P do not change.

[0070] Therefore, the pressing member E bites into the spaces between the multiple laminates 116, thereby pressing downward the regions of the first side margin sheet 117s1 that are not held by the first side surface S1 of the laminates 116. As a result, the first side margin sheet 117s1 is cut along the contour of the first side surface S1 of each laminate 116 by a shear force applied in the z-axis direction, and is divided into individual pieces.

[0071] 12(C), the pressing member E is moved upward to separate the pressing member E from the first side margin sheet 117s1. At this time, the first side margin sheet 117s1 remaining on the first side surface S1 of each laminate 116 becomes the first side margin portion 117a. The first side margin sheet 117s1 remaining in the space between the multiple laminates 116 is removed.

[0072] (Step S44: Transfer) In step S44, the multiple laminates 116 with the first side margin portions 117a formed in step S43 are transferred from the first adhesive sheet F1 to the second adhesive sheet F2. Specifically, starting from the state after step S43, first, the second adhesive sheet F2 is attached to the first side margin portions 117 formed on the first side surfaces S1 of the multiple laminates 116.

[0073] Next, the multiple laminates 116 having the first side margin portion 117a formed thereon and sandwiched between the first and second adhesive sheets F1, F2 are turned upside down. Then, the first adhesive sheet F1 is peeled off from the second side surfaces S2 of the multiple laminates 116. As a result, the second side surfaces S2 of all of the multiple laminates 116 face upward (see FIG. 13(A)).

[0074] (Step S45: Second crimping) In step S45, a second side margin sheet 117s2 constituting the second side margin portion 117b is pressure-bonded to the second side surfaces S2 of the multiple laminates 116 that were directed upward in step S44. Figures 13(A) to 13(C) are diagrams showing the process of pressure-bonding the second side margin sheet 117s2 in step S45.

[0075] The second side margin sheet 117s2 used in step S45 is configured as an unsintered dielectric green sheet, similar to the first side margin sheet 117s1. The configuration of the second side margin sheet 117s2 may be the same as or different from the configuration of the first side margin sheet 117s1.

[0076] In step S45, two rigid plates P extending along the xy plane and an elastic member D are used. The elastic member D used in step S45 is configured to be elastically deformable in the z-axis direction. As the elastic member D, for example, a sheet material made of an elastic body, such as a gel sheet made of a polymer gel, can be used.

[0077] 13(A), a series of second side margin sheets 117s2 extending along the xy plane are arranged on the second side surfaces S1 of the multiple laminates 116 so as to collectively cover the multiple laminates 116. Then, the high rigidity surfaces p of a pair of rigid plates P are opposed to each other in the z-axis direction, sandwiching the multiple laminates 116 with the first side margin portions 117a formed thereon and the second side margin sheet 117s2 therebetween.

[0078] Specifically, the rigid plate P arranged below the multiple laminates 116 holds the lower surface of the second adhesive sheet F2 on which the multiple laminates 116 are arranged by means of a high-rigidity surface p. The rigid plate P arranged above the multiple laminates 116 faces the high-rigidity surface p to the second side margin sheet 117s2 arranged on the second side surface S2 of the multiple laminates 116.

[0079] Furthermore, an elastic member D is disposed below the rigid plate P that holds the second adhesive sheet F2. The elastic member D holds the lower surface of the lower rigid plate P, and sandwiches the lower rigid plate P between itself and the second adhesive sheet F2. When a downward pressing force is applied to the elastic member D from the lower rigid plate P, compressive deformation occurs uniformly in the z-axis direction along the xy plane.

[0080] 13(B), the upper rigid plate P is moved downward, and the high-rigidity surface p of the upper rigid plate P presses the second side margin sheet 117s2 downward. As a result, the multiple laminates 116 press the lower rigid plate P via the first side margin portion 117a and the second adhesive sheet F2. As a result, a downward pressing force is applied to the elastic member D from the lower rigid plate P, causing compressive deformation in the z-axis direction.

[0081] At this time, a pressing force according to the elastic force of the compressively deformed elastic member D is applied between the second side surface S2 of the pair of multiple laminates 116 and the second side margin sheet 117s2. This allows the second side margin sheet 117s2 to be in close contact with the second side surface S2 of the multiple laminates 116.

[0082] In addition, in this embodiment, a pressing force is applied to the second side margin sheet 117s2 while the high-rigidity surface p of the upper rigid plate P is in contact with the second side margin sheet 117s2, so that a uniform pressure is applied to the second side margin sheet 117s2 between the high-rigidity surface p of the rigid plate P and the second side surface S2 of the multiple laminates 116. This makes it possible to prevent local deformation of the second side margin sheet 117s2 on the second side surface S2 of the multiple laminates 116.

[0083] Furthermore, in this embodiment, the second adhesive sheet F2 is held in contact with the high-rigidity surface p by the lower rigid plate P, so that uniform pressure is applied to the first side margin portion 117a between the second adhesive sheet F2 and the first side surface S1 of the multiple laminates 116. This makes it possible to prevent local deformation of the first side margin portion 117a.

[0084] In particular, the first side margin portion 117a has a lower density than the laminate 116 that is bonded by strong pressure, and is also diced from the first side margin sheet 117s1, which makes it easier for stress to concentrate on the ridges along the contour. Therefore, the first side margin portion 117a is prone to local deformation at the ridges along the contour.

[0085] Fig. 14 is a diagram showing a configuration of a comparative example of step S45 using a configuration similar to that of step S42 shown in Fig. 11. Specifically, in the configuration shown in Fig. 14, an elastic plate Q is used instead of a rigid plate P to hold the second adhesive sheet F2, that is, the second adhesive sheet F2 is held by the elastic surface q of the elastic plate Q.

[0086] 14, the pressing force applied to the first side margin portion 117a from the elastic surface q of the elastic plate Q via the second adhesive sheet F2 is concentrated on the ridges, causing the ridges of the first side margin portion 117a to deform more than the central portion. As a result, only the ridges of the first side margin portion 117a become thinner, resulting in an uneven thickness.

[0087] In contrast, in step S45 according to this embodiment, as shown in Fig. 13(B), the second adhesive sheet F2 is held by the high-rigidity surface p of the rigid plate P, so that stress does not concentrate on the edge of the first side margin portion 117a. Therefore, in this embodiment, the uniformity of the thickness of the first side margin portion 117a is less likely to be lost.

[0088] 13(C), the pressing rigid plate P is moved upward. As a result, the high-rigidity surface p of the rigid plate P is separated from the second side margin sheet 117s2, and the pressing force applied from the high-rigidity surface p of the rigid plate P to the second side margin sheet 117s2 is released. Accordingly, the elastic member D returns to its original shape.

[0089] In step S45, it is preferable to compressively deform the second side margin sheet 117s2 along the z-axis on the second side surfaces S of the multiple laminates 116. This allows the second side margin sheet 117s2 to be in close contact with the second side surfaces S2 of all the laminates 116 even if the heights of the second side surfaces S1 of the multiple laminates vary and the second side surfaces S2 of the multiple laminates 116 are not aligned on the same plane.

[0090] In this case, it is preferable to use, in step S45, a second side margin sheet 117s2 that is thicker than the first side margin portion 117a formed on the first side surface S1 of the multiple laminates 116. This makes it possible to keep the difference in thickness between the first side margin portion 117a and the second side margin portion 117b small even when the second side margin sheet 117s2 is compressively deformed.

[0091] Furthermore, in step S45, the second side margin sheet 117s2 is softened by heating, thereby further improving the adhesion to the second side surface S2 of the multiple laminates 116. In this embodiment, even with the second side margin sheet 117s2 softened in this manner, the effect of preventing local deformation on the first side surface S1 of the multiple laminates 116 can be effectively obtained.

[0092] In the configuration in which the second side margin sheet 117s2 is heated, the heat applied to the second side margin sheet 117s2 is transferred to the first side margin portion 117a, so that the first side margin portion 117a also tends to soften. In this embodiment, even in the first side margin portion 117a that has been softened in this way, local deformation at the ridge portion along the contour can be effectively prevented.

[0093] Furthermore, the elastic member D used in step S45 may be any member that extends along the xy plane and is elastically deformable along the z axis, and is not limited to a sheet material made of an elastic body as described above. For example, the elastic member D may be configured such that elastic bodies such as springs that are elastically deformable in the z axis direction are arranged along the xy plane, as shown in FIG.

[0094] In addition, the elastic member D may be provided on the upper side of the rigid plate P that presses the second side margin sheet 117s2, instead of on the lower side of the rigid plate P that holds the second adhesive sheet F2, as shown in Fig. 16. Furthermore, the elastic member D may be provided on both the lower side of the rigid plate P that holds the second adhesive sheet F2 and the upper side of the rigid plate P that presses the second side margin sheet 117s2, as shown in Fig. 17.

[0095] (Step S46: Second punching) In step S46, the second side margin sheet 117s2 pressure-bonded in step S45 is punched out by the second side surfaces S2 of the plurality of laminates 116. Figures 18(A) to (C) are diagrams showing the process of punching out the second side margin sheet 117s2 by the second side surfaces S2 of the plurality of laminates 116 in step S46.

[0096] In step S46, first, as shown in Fig. 18(A), the lower surface of the second adhesive sheet F2 is held by a high-rigidity surface p of a rigid plate P. In addition, a pressing member E is disposed above the second side margin sheet 117s2. The configurations of the rigid plate P and the pressing member E in step S46 are the same as those in step S43.

[0097] 18(B), the pressing member E is moved downward until it contacts the second side margin sheet 117s2, and the second side margin sheet 117s2 is further pressed downward by the pressing member E. At this time, the positions of the multiple laminates 116 on the second adhesive sheet F2 held by the high rigidity surface p of the rigid plate P do not change.

[0098] Therefore, the pressing member E bites into the spaces between the multiple laminates 116, thereby pressing downward the areas of the second side margin sheet 117s2 that are not held by the second side surface S2 of the laminates 116. As a result, the second side margin sheet 117s2 is cut along the contour of the second side surface S2 of each laminate 116 by a shear force applied in the z-axis direction.

[0099] 18(C), the pressing member E is moved upward to separate the pressing member E from the second side margin sheet 117s2. At this time, the second side margin sheet 117s2 remaining on the second side surface S2 of each laminate 116 becomes the second side margin portion 117b. The second side margin sheet 117s2 remaining in the space between the multiple laminates 116 is removed.

[0100] Then, the plurality of laminates 116 having the first and second side margin portions 117a, 117b formed therein as described above are peeled off from the second adhesive sheet F2, thereby obtaining the unfired ceramic body 111 shown in Fig. 9, and completing the side margin portion forming process in step S04 described above.

[0101] <Other embodiments> Although the embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made thereto.

[0102] For example, the high-rigidity surface p according to the present invention may be a flat surface that is not easily deformed, and is not limited to the surface of the rigid plate P as in the above embodiment. For example, the high-rigidity surface p may be the surface of another member, such as a release sheet provided on the surface of the rigid plate P, or may be the surface of a rigid part in a composite member in which a rigid part and a non-rigid part are integrally configured.

[0103] Similarly, the elastic surface q according to the present invention may be any surface that elastically deforms when pressed, and is not limited to the surface of the elastic plate Q as in the above embodiment. For example, the elastic surface q may be the surface of another member, such as a release sheet provided on the surface of the elastic plate Q, or may be the surface of an elastic part in a composite member in which an elastic part and a non-elastic part are integrally formed.

[0104] Furthermore, in step S42, a rigid plate P may be used instead of the elastic plate Q to hold the first adhesive sheet F1. In this case, an elastic member D that is elastically deformable in the z-axis direction may be used in step S42 as well, as in step S45. Furthermore, the first side margin portion 117a does not have to be formed by punching the first side margin sheet 117s1, and may be formed, for example, by applying a ceramic slurry.

[0105] Furthermore, in the above embodiment, the method for manufacturing the multilayer ceramic capacitor 10 has been described as an example of a multilayer ceramic electronic component, but the manufacturing method of the present invention can be applied to multilayer ceramic electronic components in general. Examples of such multilayer ceramic electronic components include chip varistors, chip thermistors, and multilayer inductors. [Explanation of symbols]

[0106] 10...Multilayer ceramic capacitor 11…Ceramic body 12,13…Internal electrode 14,15...External electrode 16...Laminate 17a, 17b…Side margin 18...Capacitance forming part 19…Cover part 101, 102, 103...Ceramic sheets 104...Laminated sheet 111…Ceramic body 112,113…Internal electrode 116...Laminate 117a, 117b...Side margin 117s1, 117s2…Side margin sheet S1,S2…side F1, F2: Adhesive sheet P…Rigid plate p…High rigidity surface Q: Elastic plate q…Elastic surface D…Elastic material E: Pressing member

Claims

1. a first side margin portion is formed on the first side of a plurality of laminates arranged on a first adhesive sheet that holds the second side, the laminate having a plurality of ceramic layers stacked in a first axial direction, a plurality of internal electrodes located between the plurality of ceramic layers, and a first and second side faces that face a second axial direction perpendicular to the first axis and expose the plurality of internal electrodes; transferring the plurality of laminates having the first side margin portions formed thereon from the first adhesive sheet to a second adhesive sheet; placing a series of second side margin sheets on the second side surfaces of the plurality of laminates transferred to the second adhesive sheet; a pair of high-rigidity surfaces opposed in the second axial direction are brought into contact with the second adhesive sheet and the second side margin sheet, and a pressing force is applied to the pair of high-rigidity surfaces via an elastic member that is elastically deformable along the second axis, thereby pressing the second side margin sheet against the second side surfaces of the plurality of laminates; The second side margin portion is formed by punching out the compressed second side margin sheet at the second side surface of the plurality of laminates. A method for manufacturing multilayer ceramic electronic components.

2. 2. A method for producing a multilayer ceramic electronic component according to claim 1, comprising the steps of: The second side margin sheet is heated when the second side margin sheet is pressed. A method for manufacturing multilayer ceramic electronic components.

3. 3. A method for producing a multilayer ceramic electronic component according to claim 1, further comprising the steps of: When the second side margin sheet is pressed, the second side margin sheet is compressed and deformed. A method for manufacturing multilayer ceramic electronic components.

4. 4. A method for producing a multilayer ceramic electronic component according to claim 3, comprising the steps of: The second side margin sheet before compression is thicker than the first side margin portion. A method for manufacturing multilayer ceramic electronic components.

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