Multilayer ceramic electronic component and its manufacturing method

Abstract

To provide a multilayer ceramic electronic component that can prevent a reduction in performance caused by stress applied during calcination.SOLUTION: A multilayer ceramic electronic component is provided with a laminate 16, and side margin parts 17a, 17b. The laminate has a plurality of ceramic layers stacked in a first axis direction, a plurality of internal electrodes 12, 13 located between the plurality of ceramic layers, and first and second side faces S1, S2 where the ends of the plurality of internal electrodes in a second axis direction orthogonal to the first axis are located. The side margin parts cover the first and second side faces. When the first and second margin parts are each equally divided into two along a plane perpendicular to the first axis direction to obtain first and second areas, in the first side margin part, the first area has a larger average thickness than the second area, and in the second side margin part, the second area has a larger average thickness than the first area.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a multilayer ceramic electronic component to which a side margin portion is retrofitted. [Background technology]

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

[0003] For example, in the method for manufacturing a multilayer ceramic capacitor described in Patent Document 1, a laminate sheet made by stacking ceramic sheets on which internal electrodes are printed is cut to produce multiple laminates with the cut surfaces where the internal electrodes are exposed as side surfaces.Then, the ceramic sheets are punched out at the side surfaces of the laminates to form side margins on the side surfaces of the laminates. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-209539 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the technology of adding side margins as described above, the laminate and the side margins exhibit different shrinkage behaviors during firing, i.e., the low-density side margins tend to shrink more than the high-density laminate, which can cause stress inside the laminate and reduce the performance of the multilayer ceramic capacitor.

[0006] In view of the above circumstances, an object of the present invention is to provide a multilayer ceramic electronic component that can suppress performance degradation due to stress applied during firing. [Means for solving the problem]

[0007] In order to achieve the above object, a multilayer ceramic electronic component according to one embodiment of the present invention includes a laminate and a side margin portion. The laminate has a plurality of ceramic layers stacked in a first axial direction, a plurality of internal electrodes positioned between the plurality of ceramic layers, and first and second side surfaces on which the ends of the plurality of internal electrodes in a second axial direction perpendicular to the first axis are located. The side margin portion covers the first and second side surfaces. When the first and second side margin portions are divided into first and second regions by dividing them into two equal parts along a plane perpendicular to the first axis direction, the first side margin portion has a greater average thickness in the first region than in the second region, and the second side margin portion has a greater average thickness in the second region than in the first region.

[0008] During firing in the manufacturing process of a multilayer ceramic electronic component, a force due to contraction of the first and second side margin portions is applied to the first and second side surfaces of the laminate, causing tensile stress to be applied inside the laminate. As a result, in the laminate, grain growth of the crystals constituting the first and second internal electrodes tends to occur along the direction of the tensile stress applied inside. In the laminate, if the grain growth of the first and second internal electrodes progresses too much in the thickness direction (first axial direction), the first and second internal electrodes tend to become discontinuous in the in-plane direction. In contrast, a greater force is applied to the first side surface of the laminate in the first region where the first side margin is thicker than to the second region. Meanwhile, a greater force is applied to the second side surface of the laminate in the second region where the second side margin is thicker than to the first region. As a result, the direction of the tensile stress applied to the laminate during firing is tilted relative to the first axial direction, suppressing grain growth in the thickness direction of the first and second internal electrodes. Therefore, in a multilayer ceramic electronic component with this configuration, the continuity of the first and second internal electrodes in the in-plane direction can be ensured.

[0009] The first and second side margin portions may have outer surfaces extending along a plane perpendicular to the second axis. In this configuration, the first and second side margin portions can be configured to have the thickness distribution described above while the ceramic body is maintained in a general rectangular parallelepiped shape.

[0010] The average thickness of the first region of the first side margin portion may be greater than the average thickness of the first region of the second side margin portion, and the average thickness of the second region of the second side margin portion may be greater than the average thickness of the second region of the first side margin portion. The average thickness of the first region of the first side margin portion may be equivalent to the average thickness of the second region of the second side margin portion, and the average thickness of the second region of the first side margin portion may be equivalent to the average thickness of the first region of the second side margin portion.

[0011] In a method for manufacturing a multilayer ceramic electronic component according to one aspect of the present invention, a multilayer sheet is produced, the multilayer sheet having a plurality of ceramic sheets stacked in a first axis direction and a plurality of internal electrodes positioned between the plurality of ceramic layers. By cutting the laminate sheet into individual pieces, a laminate is produced having a cut surface that exposes the ends of the multiple internal electrodes in the second axis direction perpendicular to the first axis, and having first and second side surfaces that are inclined in a common direction relative to a plane perpendicular to the second axis. First and second side margin portions having outer surfaces extending along a plane perpendicular to the second axis are formed on the first and second side surfaces.

[0012] The laminated sheet may be cut by a press cutter blade vibrated in the second direction. A side margin sheet may be used to form the first and second side margin portions. In this case, the side margin sheet may be attached to the first and second side surfaces while being deformed to conform to the shapes of the first and second side surfaces. The side margin sheet may also be pressed by a highly rigid pressing surface extending along a plane perpendicular to the second axis. [Effects of the Invention]

[0013] As described above, the present invention can provide a multilayer ceramic electronic component that can suppress performance degradation due to stress applied during firing. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view of a multilayer ceramic capacitor according to an embodiment of the present invention; [Figure 2] 2 is a cross-sectional view of the multilayer ceramic capacitor taken along line AA' in FIG. [Figure 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. [Figure 5] FIG. 2 is a plan view of a ceramic sheet prepared in a ceramic sheet preparation step of the manufacturing method. [Figure 6] FIG. 2 is a perspective view showing a lamination step of the manufacturing method. [Figure 7] FIG. 3 is a plan view showing a cutting step in the manufacturing method. [Figure 8] 3A to 3C are partial cross-sectional views showing a cutting step in the manufacturing method. [Figure 9]FIG. 2 is a perspective view of an unfired ceramic body obtained in the side margin portion forming step of the manufacturing method. [Figure 10] FIG. 10 is a cross-sectional view showing a comparative example of the firing step of the manufacturing method. [Figure 11] FIG. 3 is a cross-sectional view showing a firing step in the manufacturing method. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, a multilayer ceramic capacitor 10 according to one embodiment of the present invention will be described with reference to the drawings. In addition, mutually orthogonal X-axis, Y-axis, and Z-axis are appropriately shown in Figures 1 to 11. The X-axis, Y-axis, and Z-axis define a fixed coordinate system fixed with respect to the multilayer ceramic capacitor 10.

[0016] [Configuration of multilayer ceramic capacitor 10] 1 to 3 are diagrams showing a multilayer ceramic capacitor 10 according to one 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.

[0017] 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 formed in the shape of a rectangular parallelepiped having first and second end faces orthogonal to the X-axis, first and second side faces s1 and s2 orthogonal to the Y-axis, and first and second main faces orthogonal to the Z-axis.

[0018] The end faces, side faces s1 and s2, and main surface of the ceramic body 11 are all flat surfaces. The flat surfaces according to this embodiment do not necessarily have to be strictly planar as long as they are recognized as flat when viewed overall, and include, for example, surfaces with minute irregularities or gently curved shapes within a predetermined range.

[0019] 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 s1, s2. As a result, the cross sections of the external electrodes 14, 15 parallel to the XZ plane and the cross sections parallel to the XY plane are both U-shaped.

[0020] 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 do not have to extend to either of the main surfaces or the side surfaces s1, s2.

[0021] The external electrodes 14, 15 are made of a good electrical conductor. Examples of good electrical conductors that form the external electrodes 14, 15 include metals or alloys containing copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), silver (Ag), gold (Au), or the like as a main component.

[0022] The ceramic body 11 is made of dielectric ceramic and includes a laminate 16 and first and second side margins 17a, 17b. The laminate 16 has first and second end faces perpendicular to the X-axis and first and second main surfaces perpendicular to the Z-axis. The laminate 16 also has first and second side surfaces S1, S2 facing each other in the Y-axis direction.

[0023] In the laminate 16, the first and second side surfaces S1, S2 are both configured as inclined surfaces that are inclined in the same direction (from the lower side to the upper side in the Z axis direction and to the left in the Y axis direction). As a result, in the laminate 16, the first side surface S1 protrudes toward the left in the Y axis direction from the upper side in the Z axis direction, and the second side surface S2 is recessed toward the left in the Y axis direction from the upper side in the Z axis direction.

[0024] 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 generating portion 18 from above and below in the Z-axis direction, and constitutes the first and second main surfaces of the laminate 16 .

[0025] The capacitance forming portion 18 is disposed between the 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 layer sandwiched between them.

[0026] The first internal electrode 12 is drawn out to an end surface covered with the first external electrode 14. On the other hand, the second internal electrode 13 is drawn out to an end surface covered with 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.

[0027] With this configuration, when a voltage is applied between the first external electrode 14 and the second external electrode 15 in the multilayer ceramic capacitor 10, the voltage is applied to the plurality of 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.

[0028] The ceramic body 11 uses a dielectric ceramic with a high dielectric constant to increase the capacitance of each ceramic layer between the internal electrodes 12 and 13. Examples of dielectric ceramic with a high dielectric constant include materials with a perovskite structure containing barium (Ba) and titanium (Ti), such as barium titanate (BaTiO).

[0029] The ceramic layer may be composed of a composition such as strontium titanate (SrTiO3), calcium titanate (CaTiO3), magnesium titanate (MgTiO3), calcium zirconate (CaZrO3), calcium titanate zirconate (Ca(Zr,Ti)O3), barium zirconate (BaZrO3), or titanium oxide (TiO2).

[0030] 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 containing copper (Cu), palladium (Pd), platinum (Pt), silver (Ag), gold (Au), or the like as their main components.

[0031] The internal electrodes 12, 13 are formed across the entire width of the capacitance forming portion 18 in the Y-axis direction, and their ends in the Y-axis direction are located on the side surfaces S1, S2 of the laminate 16. The side margin portions 17a, 17b cover the side surfaces S1, S2 of the laminate 16. This ensures insulation between the internal electrodes 12, 13 on both side surfaces S1, S2 of the laminate 16.

[0032] Specifically, 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. In other words, the outer surface of the first side margin portion 17a forms the first side surface s1 of the ceramic body 11, and the outer surface of the second side margin portion 17b forms the second side surface s2 of the ceramic body 11.

[0033] 3 is asymmetric with respect to the central axis that passes through the center of the Y-axis direction of the ceramic body 11 and is parallel to the Z-axis direction. That is, the side margins 17a and 17b have different thickness distributions along the Z-axis direction, which are the dimensions in the Y-axis direction.

[0034] 3 shows a bisection plane D, which is a plane perpendicular to the Z axis that divides the side margins 17a, 17b into first and second regions R1, R2 by dividing them vertically in the Z axis direction. That is, in the side margins 17a, 17b according to this embodiment, the lower half of the region in the Z axis direction is the first region R1, and the upper half of the region in the Z axis direction is the second region R2.

[0035] The side margins 17a and 17b have different average thicknesses in the first region R1 and the second region R2. Specifically, the first side margin 17a has a larger average thickness in the first region R1 than in the second region R2. The second side margin 17b has a larger average thickness in the second region R2 than in the first region R1.

[0036] In other words, in the first region R1 on the lower side in the Z-axis direction, the first side margin 17a has a large average thickness and the second side margin 17b has a small average thickness. On the other hand, in the second region R2 on the upper side in the Z-axis direction, the first side margin 17a has a small average thickness and the second side margin 17b has a large average thickness.

[0037] In the multilayer ceramic capacitor 10, by forming the side surfaces S1, S2 of the laminate 16 into inclined surfaces, it is possible to provide the thickness distribution described above in the side margin portions 17a, 17b while maintaining the general rectangular parallelepiped shape of the ceramic body 11. This makes the multilayer ceramic capacitor 10 an easy replacement for existing products.

[0038] In the multilayer ceramic capacitor 10, it is only necessary that the average thicknesses of the side margin portions 17a, 17b in the regions R1, R2 satisfy the above relationship, and the shapes of the side surfaces S1, S2 of the laminate 16 can be changed in various ways. For example, the cross-sectional shape of the side surfaces S1, S2 of the laminate 16 may be linear or wavy.

[0039] In the multilayer ceramic capacitor 10, by making the magnitude relationship between the average thicknesses of the regions R1 and R2 different between the side margin portions 17a and 17b as described above, it is possible to control the direction of the tensile stress applied to the inside of the laminate 16 during firing in the manufacturing process, thereby suppressing performance degradation of the multilayer ceramic capacitor 10.

[0040] [Method of manufacturing the 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 11 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 11.

[0041] (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.

[0042] The ceramic sheets 101, 102, and 103 are formed into sheets 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 capacitor forming portion 18 after firing. The thickness of the third ceramic sheet 103 can be adjusted as appropriate.

[0043] 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 yet been singulated. Fig. 5 also shows cutting lines Lx and Ly along which the sheets are separated 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.

[0044] 5, an unfired first internal electrode 112 corresponding to the first internal electrode 12 is formed on the first ceramic sheet 101, and an unfired second internal electrode 113 corresponding to the second internal electrode 13 is formed on the second ceramic sheet 102. Note that no internal electrode is formed on the third ceramic sheet 103 corresponding to the cover portion 19.

[0045] 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 known techniques. For example, the conductive paste can be applied by screen printing or gravure printing.

[0046] Gaps in the X-axis direction along the cutting lines Ly are formed in the internal electrodes 112, 113 at every other cutting line Ly. The gaps in the first internal electrodes 112 and the gaps in the second internal electrodes 113 are arranged alternately in the X-axis direction. In other words, the cutting lines Ly passing through the gaps in the first internal electrodes 112 and the cutting lines Ly passing through the gaps in the second internal electrodes 113 are arranged alternately.

[0047] (Step S02: Lamination) In step S02, the ceramic sheets 101, 102, and 103 prepared in step S01 are stacked as shown in Fig. 6 to produce a laminated sheet 104. In the laminated sheet 104, the first ceramic sheets 101 and the second ceramic sheets 102 corresponding to the capacitance forming portions 18 are stacked alternately in the Z-axis direction.

[0048] 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 on each side, but the number of third ceramic sheets 103 can be changed as appropriate.

[0049] The laminated sheet 104 is integrated by compressing the ceramic sheets 101, 102, and 103. For example, hydrostatic pressure or uniaxial pressure is preferably used to compress the ceramic sheets 101, 102, and 103. This allows the laminated sheet 104 to be highly densified.

[0050] (Step S03: Cutting) 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 cutter blade or a rotary blade can be used to cut the laminate sheet 104.

[0051] 7 and 8 are schematic diagrams illustrating an example of step S03. Fig. 7 is a plan view of the laminated sheet 104. Fig. 8 is a cross-sectional view of the laminated sheet 104 along the YZ plane. The laminated sheet 104 is held by an adhesive cutting sheet C, such as a foam release sheet, and is cut by a push-cutter blade BL along cutting lines Lx and Ly.

[0052] First, as shown in Fig. 8(A), the push-cutting blade BL is positioned above the laminated sheet 104 in the Z-axis direction, with its tip pointing downward in the Z-axis direction toward the laminated sheet 104. Next, from the state shown in Fig. 8(A), 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.

[0053] 8(B), the cutting blade BL is moved upward in the Z-axis direction to pull it out from the laminated sheet 104. This cuts the laminated sheet 104 in the X-axis and Y-axis directions, forming a laminate 116 having first and second side surfaces S1, S2 that expose the internal electrodes 112, 113 in the Y-axis direction.

[0054] 8, the push-cutting blade BL is vibrated left and right in the Y-axis direction at a predetermined vibration frequency and amplitude during the process of cutting the laminated sheet 104. This makes the cut surface of the laminated sheet 104 cut by the push-cutting blade BL into a curved shape, thereby making it possible to form the side surfaces S1 and S2 of the laminate 116 into inclined surfaces as shown in FIG.

[0055] (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, thereby producing an unsintered ceramic body 111 having side surfaces s1 and s2 extending along a plane perpendicular to the Y axis, as shown in FIG.

[0056] The side margin portions 117a, 117b can be formed using, for example, a ceramic sheet (side margin sheet) or ceramic slurry. When a side margin sheet is used, the side margin sheet can be attached to the side surfaces S1, S2 of the laminate 116 while being deformed to conform to the shape of the side surfaces S1, S2 of the laminate 116 by pressing the side margin sheet against the side surfaces S1, S2 of the laminate 116 with a highly rigid pressing surface extending along the XZ plane.

[0057] To prevent delamination in the laminate 116, the side margins 117a and 117b cannot be pressed against the side surfaces S1 and S2 of the laminate 116 with high pressure. Therefore, in the ceramic body 111, the side margins 117a and 117b have a lower density than the laminate 116.

[0058] (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 and 117b become the side margin portions 17a and 17b.

[0059] 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 approximately 1000 to 1300° C. Furthermore, firing can be performed, for example, in a reducing atmosphere or a low oxygen partial pressure atmosphere.

[0060] 10 shows a state of a ceramic body 211 according to a modified example of the present embodiment during firing. Unlike the ceramic body 111 according to the present embodiment, the ceramic body 211 according to the modified example has side margin portions 217a, 217b of uniform thickness provided on side surfaces S1, S2 of a laminate 216 that are orthogonal to the Y axis.

[0061] During firing, due to shrinkage of low-density side margin portions 217a, 217b in ceramic body 211, a compressive force in the Z-axis direction along the in-plane direction is applied to side surfaces S1, S2 of laminate 216. Accordingly, in laminate 216, a tensile stress opposite to the compressive force applied to side surfaces S1, S2 is applied mainly to the central region in the Y-axis direction of capacitance formation portion 218.

[0062] In the ceramic body 211 according to the comparative example, the thicknesses of the side margin portions 217a, 217b are uniform, and therefore the compressive force applied to the side surfaces S1, S2 of the laminate 116 is equal in the first region R1 and the second region R2. Therefore, in the ceramic body 211, the direction of the tensile stress applied to the capacitance generating portion 218 is the Z-axis direction.

[0063] Therefore, in the ceramic body 211 during firing, the tensile stress in the Z-axis direction applied to the capacitance forming portion 218 tends to cause grain growth of the crystals constituting the internal electrodes 212, 213 along the thickness direction. As a result, the periphery of the crystals that have grown in the thickness direction becomes thinner, and the internal electrodes 212, 213 tend to become discontinuous in the in-plane direction.

[0064] 11 shows the ceramic body 111 according to this embodiment during firing. As described above, in the ceramic body 111, the average thickness of the first side margin 117a is greater in the first region R1 than in the second region R2, and the average thickness of the second side margin 117b is greater in the second region R2 than in the first region R1.

[0065] Therefore, in the ceramic body 111 during firing, the contraction force of the first side margin 117a is greater in the first region R1 having a larger average thickness than in the second region R2 having a smaller average thickness, while the contraction force of the second side margin 117b is greater in the second region R2 having a larger average thickness than in the first region R1 having a smaller average thickness.

[0066] Therefore, in the laminate 116, the compressive force applied to the first side surface S1 is greater in the first region R1 than in the second region R2, and the compressive force applied to the second side surface S2 is greater in the second region R2 than in the first region R1. Therefore, in the ceramic body 111, the direction of the tensile stress applied to the capacitance forming portion 118 is inclined toward the Y-axis direction with respect to the Z-axis direction.

[0067] Therefore, in the ceramic body 111 during firing, the direction of grain growth of the crystals constituting the internal electrodes 112, 113 due to the pressure applied to the capacitance forming portion 118 has a component in the in-plane direction as well as a component in the thickness direction. Therefore, even if the crystal grains grow in the internal electrodes 112, 113, continuity in the in-plane direction is likely to be maintained.

[0068] As a result, in the multilayer ceramic capacitor 10, a decrease in capacitance due to discontinuity in the in-plane direction of the internal electrodes 112, 113 in the capacitance forming portion 118 is unlikely to occur during firing of the ceramic body 111. Therefore, in the multilayer ceramic capacitor 10, it is possible to suppress performance degradation due to stress applied during firing.

[0069] In the multilayer ceramic capacitor 10, it is preferable that the tensile stress during firing does not deviate significantly from the central region of the capacitance forming portion 118. Therefore, it is preferable that the compressive force applied to the laminate 116 from the side margin portions 17a, 17b during firing does not differ significantly between the first region R1 and the second region R2.

[0070] Therefore, in the multilayer ceramic capacitor 10, it is preferable that the average thickness of the first region R1 of the first side margin portion 17a is greater than the average thickness of the first region R1 of the second side margin portion 17b, and that the average thickness of the second region R2 of the second side margin portion 17b is greater than the average thickness of the second region R2 of the first side margin portion 17a.

[0071] Furthermore, in the multilayer ceramic capacitor 10, it is preferable that the average thickness of the first region R1 of the first side margin portion 17a is equal to the average thickness of the second region R2 of the second side margin portion 17b, and that the average thickness of the second region R2 of the first side margin portion 17a is equal to the average thickness of the first region R1 of the second side margin portion 17b.

[0072] In addition, "equivalent" in the comparison of the average thicknesses of the side margin portions 17a and 17b means that the average thickness of the second side margin portion 17b is within ±5% of the average thickness of the first side margin portion 17a.

[0073] (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 completing 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 selected from any known method.

[0074] [Other embodiments] Although the embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to the above-described embodiments and that various modifications can be made.

[0075] For example, in the multilayer ceramic capacitor 10 according to this embodiment, the average thickness of the side margin portions 117a, 117b may be the above configuration. Therefore, in the multilayer ceramic capacitor 10, the shapes of the side surfaces S1, S2 of the laminate 16 and the side surfaces s1, s2 of the ceramic body 11 may be different from the above configuration.

[0076] Although the multilayer ceramic capacitor 10 has been described as an example of a multilayer ceramic electronic component in the above embodiment, the present invention is applicable to multilayer ceramic electronic components in general, such as chip varistors, chip thermistors, and multilayer inductors. [Explanation of symbols]

[0077] 10...Multilayer ceramic capacitor 11...Ceramic body 12,13…Internal electrode 14,15...External electrode 16...Laminate 17a, 17b...Side margin 18...Capacity forming part 19...Cover part S1, S2...side surface of laminate s1, s2...Side surfaces of ceramic element R1,R2…area

Claims

1. a laminate including a capacitance forming portion having a plurality of ceramic layers stacked in a first axial direction and a plurality of internal electrodes positioned between the plurality of ceramic layers, and cover portions covering the capacitance forming portion from both sides in the first axial direction, and having first and second side surfaces on which end portions of the plurality of internal electrodes in a second axial direction perpendicular to the first axis are located, at least one of the first and second side surfaces being different from a plane perpendicular to the first axis and a plane perpendicular to the second axis; first and second side margin portions covering the first and second side surfaces; Equipped with When the first and second side margin portions are divided into first and second regions along a plane that bisects the first axial direction, the first side margin portion has a larger average thickness in the first region than in the second region, and the second side margin portion has a larger average thickness in the second region than in the first region, the density of the first and second side margin portions is lower than the density of the laminate; a thickness of the cover portion along the first axial direction that is greater than a maximum thickness of the first side margin portion and a maximum thickness of the second side margin portion; Multilayer ceramic electronic components.

2. 2. The multilayer ceramic electronic component according to claim 1, The first and second side margin portions have outer surfaces extending along a plane perpendicular to the second axis. Multilayer ceramic electronic components.

3. 3. The multilayer ceramic electronic component according to claim 1, the average thickness of the first region of the first side margin portion is greater than the average thickness of the first region of the second side margin portion; The average thickness of the second region of the second side margin portion is greater than the average thickness of the second region of the first side margin portion. Multilayer ceramic electronic components.

4. 4. The multilayer ceramic electronic component according to claim 1, the average thickness of the first region of the first side margin is equal to the average thickness of the second region of the second side margin, The average thickness of the second region of the first side margin is equal to the average thickness of the first region of the second side margin. Multilayer ceramic electronic components.

5. 5. The multilayer ceramic electronic component according to claim 1, The first and second side surfaces of the laminate are inclined surfaces. Multilayer ceramic electronic components.

6. 6. The multilayer ceramic electronic component according to claim 1, The ceramic body including the laminate and the first and second side margin portions has a rectangular parallelepiped shape. Multilayer ceramic electronic components.

7. A laminated sheet is prepared, the laminated sheet including a plurality of first ceramic sheets stacked in a first axial direction, a plurality of internal electrodes positioned between the plurality of first ceramic sheets, and second ceramic sheets forming cover portions at both ends in the first axial direction, cutting the laminate sheet into individual pieces, thereby producing a laminate having a cut surface that exposes ends of the plurality of internal electrodes in a second axis direction perpendicular to the first axis, and first and second side surfaces that are inclined in a common direction with respect to a plane perpendicular to the second axis; First and second side margin portions are formed on the first and second side surfaces, the first and second side margin portions having outer surfaces extending along a plane perpendicular to the second axis; a thickness of the cover portion along the first axial direction that is greater than a maximum thickness of the first side margin portion and a maximum thickness of the second side margin portion; Manufacturing method for multilayer ceramic electronic components.

8. 8. A method for manufacturing a multilayer ceramic electronic component according to claim 7, comprising: The laminated sheet is cut by a press cutter blade vibrated in the second axial direction. Manufacturing method for multilayer ceramic electronic components.

9. 9. A method for manufacturing a multilayer ceramic electronic component according to claim 7 or 8, comprising: a side margin sheet is used to form the first and second side margin portions; The side margin sheet is attached to the first and second side surfaces while being deformed to conform to the shapes of the first and second side surfaces. Manufacturing method for multilayer ceramic electronic components.

10. 10. The method for manufacturing a multilayer ceramic electronic component according to claim 9, The side margin sheet is pressed by a high-rigidity pressing surface extending along a plane perpendicular to the second axis. Manufacturing method for multilayer ceramic electronic components.

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