Multilayer ceramic capacitor

Abstract

Provided is a multilayer ceramic capacitor capable of increasing capacity without increasing the possibility of generating an electrical short circuit. This laminated ceramic capacitor (1) is provided with: a laminated body (2) having internal electrode layers (15) and dielectric layers (14) that are alternately laminated; and external electrodes (3, 4) respectively disposed on at least a pair of outer surfaces (B, C) facing each other among the outer surfaces (B, C) extending in the lamination direction in the laminated body (2), the internal electrode layers (15) having facing portions (15a) in which the internal electrode layers (15) adjacent in the lamination direction overlap each other, and lead-out portions (15b) extending from the facing portions (15a) toward the external electrodes (3, 4). The edge (16) of the facing portion (15a) has a concavo-convex portion (150) including, alternately, convex portions (151) facing the outer surfaces (B, C) adjacent to the edge (16) and concave portions (152) away from the outer surfaces (B, C).

Description

Technical Field

[0001] The present invention relates to a laminated ceramic capacitor. Background Art

[0002] In recent years, the low impedance of electronic circuit lines has been accelerated, mainly in mobile device products, and the need for increasing the capacity of multilayer ceramic capacitors, such as for decoupling purposes, has increased. As a countermeasure for increasing the capacity of multilayer ceramic capacitors, for example, measures have been taken to make the dielectric layer thinner or to increase the area of ​​the internal electrode layer (for example, see Patent Document 1).

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2003-234241 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] However, these countermeasures increase the possibility of causing an electrical short circuit or the like due to defects in the internal electrodes or the like.

[0008] An object of the present invention is to provide a multilayer ceramic capacitor capable of increasing the capacitance without increasing the possibility of an electrical short circuit.

[0009] Technical solutions to solve problems

[0010] In order to solve the above-mentioned problems, the present invention provides a stacked ceramic capacitor, comprising: a stacked body having internal electrode layers and dielectric layers stacked alternately; and external electrodes, respectively arranged on at least a pair of outer surfaces opposing each other among the outer surfaces extending in the stacking direction in the stacked body, the internal electrode layers having opposing portions in which adjacent internal electrode layers in the stacking direction overlap with each other, and lead portions extending from the opposing portions toward the external electrodes, the edges of the opposing portions having concave-convex portions alternatingly including convex portions toward the outer surface adjacent to the edge and concave portions away from the outer surface.

[0011] Effects of the Invention

[0012] According to the present invention, it is possible to provide a multilayer ceramic capacitor capable of increasing the capacitance without increasing the possibility of an electrical short circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic perspective view of the multilayer ceramic capacitor 1 .

[0014] Figure 2 is the edge of the multilayer ceramic capacitor 1 Figure 1Cross-sectional view after cutting along the II-II direction.

[0015] Figure 3 is the edge of the multilayer ceramic capacitor 1 Figure 1 Cross-sectional view after cutting along the III-III direction.

[0016] Figure 4 1 is a cross-sectional view of the multilayer ceramic capacitor 1 along the end surface connecting the internal electrode layers 15A.

[0017] Figure 5 1 is a cross-sectional view of the multilayer ceramic capacitor 1 along the side surface connecting the internal electrode layer 15B.

[0018] Figure 6 This is a transparent view of the internal electrode layer 15 when viewed from the main surface A side provided on both sides in the stacking direction T.

[0019] Figure 7 It is along Figure 6 Cross-sectional view of line IV-IV.

[0020] Figure 8 1 is a flowchart for explaining a method for manufacturing the multilayer ceramic capacitor 1 .

[0021] Fig. 9 The diagrams are for explaining the internal electrode pattern forming step S1 and the laminating step S2 in the method for manufacturing the multilayer ceramic capacitor 1 .

[0022] Fig.10 This is a diagram showing electric lines of force generated between internal electrode layers when there are two internal electrode layers.

[0023] Fig.11 This is a table showing the results of measuring the capacitance of the multilayer ceramic capacitors of Examples and Comparative Examples.

[0024] Fig.12 This is a table showing the results of measuring the capacitance of the multilayer ceramic capacitors of Examples and Comparative Examples.

[0025] Fig.13 This is a table showing the results of measuring the capacitance of the multilayer ceramic capacitors of Examples and Comparative Examples.

[0026] Fig.14 It is an exploded perspective view of a laminated body 2 in a laminated ceramic capacitor according to a modified embodiment of the present invention. DETAILED DESCRIPTION

[0027] Hereinafter, a multilayer ceramic capacitor 1 according to an embodiment of the present invention will be described. Figure 1 It is a schematic perspective view of the multilayer ceramic capacitor 1 . Figure 2is the edge of the multilayer ceramic capacitor 1 Figure 1 Cross-sectional view after cutting along the II-II direction. Figure 3 is the edge of the multilayer ceramic capacitor 1 Figure 1 Cross-sectional view after cutting along the III-III direction.

[0028] (Multilayer ceramic capacitor 1)

[0029] The multilayer ceramic capacitor 1 includes end surface external electrodes 3 provided on both end surfaces C in the length direction L of the multilayer body 2, and side surface external electrodes 4 provided on both side surfaces B in the width direction W of the multilayer body 2. The multilayer body 2 includes an inner layer portion 11 in which a dielectric layer 14 and an internal electrode layer 15 are stacked, and an outer layer portion 12.

[0030] In addition, in this specification, as a term indicating the orientation of the laminated ceramic capacitor 1, in the laminated ceramic capacitor 1, the direction in which the dielectric layer 14 and the internal electrode layer 15 are laminated is referred to as the lamination direction T. The direction intersecting the lamination direction T and in which the pair of end surface external electrodes 3 are provided is referred to as the length direction L. The direction intersecting both the length direction L and the lamination direction T is referred to as the width direction W. In the embodiment, the lamination direction T, the length direction L, and the width direction W are orthogonal to each other.

[0031] Furthermore, in the following description, a pair of outer surfaces among the six outer surfaces of the stacked body 2 arranged on both sides of the stacking direction T are set as main surfaces A, a pair of outer surfaces extending in the stacking direction T and arranged on both sides of the width direction W are set as side surfaces B, and a pair of outer surfaces extending in the stacking direction T and arranged on both sides of the length direction L are set as end surfaces C.

[0032] (Laminate 2)

[0033] The laminate 2 includes an inner layer portion 11 and outer layer portions 12 disposed on both sides of the inner layer portion 11 in the lamination direction T. The laminate 2 preferably has rounded corners and ridges. The corners are where three faces of the laminate intersect, and the ridges are where two faces of the laminate intersect.

[0034] (Inner layer portion 11)

[0035] The inner layer portion 11 is formed by laminating a plurality of dielectric layers 14 and internal electrode layers 15 along the lamination direction T.

[0036] (Dielectric layer 14)

[0037] The dielectric layer 14 is made of a ceramic material. As the ceramic material, for example, a dielectric ceramic having BaTiO3 as a main component can be used. In addition, as the ceramic material, a material in which at least one of the auxiliary components such as Mn compounds, Fe compounds, Cr compounds, Co compounds, and Ni compounds is added to these main components can also be used.

[0038] (Internal electrode layer 15)

[0039] The internal electrode layer 15 is preferably formed of a metal material represented by Ni, Cu, Ag, Pd, Ag—Pd alloy, Au, or the like.

[0040] The internal electrode layer 15 includes a plurality of end surface-connected internal electrode layers 15A and a plurality of side surface-connected internal electrode layers 15B that are alternately arranged. When there is no need to distinguish between the end surface-connected internal electrode layers 15A and the side surface-connected internal electrode layers 15B, they are collectively described as the internal electrode layers 15.

[0041] Figure 4 1 is a cross-sectional view of the multilayer ceramic capacitor 1 along the end surface connecting the internal electrode layers 15A. Figure 5 1 is a cross-sectional view of the multilayer ceramic capacitor 1 along the side surface connecting the internal electrode layer 15B.

[0042] (End surface connected to internal electrode layer 15A)

[0043] like Figure 4 As shown, the end surface connection internal electrode layer 15A extends between the two end surfaces C in the length direction L of the stack 2, and is separated from the two side surfaces B in the width direction W by a certain distance. The end surface connection internal electrode layer 15A has an end surface facing portion 15Aa separated from the two end surfaces C by a certain distance, and an end surface lead portion 15Ab extending from the end surface facing portion 15Aa to the end surfaces C on both sides. The end surface lead portion 15Ab extends to the end surfaces C on both sides and is exposed at the end surface C of the stack 2, and is connected to the end surface external electrodes 3 provided on the two side surfaces in the width direction W of the stack 2.

[0044] (Side connection internal electrode layer 15B)

[0045] like Figure 5 As shown, the side-connected internal electrode layer 15B has a side facing portion 15Ba which is smaller than the stack 2 and each side is separated from the end surface C and the side surface B by a certain distance, and a side lead portion 15Bb extending from the side facing portion 15Ba to the side surfaces B on both sides. The side lead portions 15Bb extend to the side surfaces B on both sides and are exposed on the side surfaces B of the stack 2, and are connected to the side external electrodes 4 provided on the two side surfaces in the width direction W of the stack 2.

[0046] The end surface opposing portion 15Aa and the side surface opposing portion 15Ba face each other, forming a capacitor portion.

[0047] In the following description, when there is no need to distinguish between the end face facing portion 15Aa and the side face facing portion 15Ba, they are collectively described as the facing portion 15a. Also, when there is no need to distinguish between the end face lead-out portion 15Ab and the side face lead-out portion 15Bb, they are collectively described as the lead-out portion 15b.

[0048] like Figure 4 as well as Figure 5 As shown, the edge 16 of the facing portion 15 a of the embodiment has a concave-convex portion 150 that alternately includes convex portions 151 that face the outer surface adjacent to the edge 16 and concave portions 152 that are away from the outer surface.

[0049] Specifically, Figure 4 The end surface opposing portion 15Aa of the end surface connected internal electrode layer 15A shown has an uneven portion 150 including, at an edge 16AL extending in the longitudinal direction L, convex portions 151 facing the side surface B adjacent to the edge 16AL and concave portions 152 away from the side surface B alternately.

[0050] To explain in more detail, the edge 16AL includes five convex portions 151 between the two end faces C and four concave portions 152 respectively arranged between adjacent convex portions 151 .

[0051] The uneven portion 150 of the edge 16AL preferably has two or more sets of convex portions 151 and concave portions 152 continuously, and in the embodiment, has four sets continuously.

[0052] Figure 5 The side facing portion 15Ba of the side-connected internal electrode layer 15B shown has, at an edge 16BL extending in the longitudinal direction L, an uneven portion 150 including convex portions 151 facing the side surface B adjacent to the edge 16BL and concave portions 152 away from the side surface B alternately.

[0053] To explain in more detail, the edge 16BL is provided with a concave portion 152 , a convex portion 151 , a concave portion 152 , and a convex portion 151 in this order from the side lead-out portion 15Bb toward both end surfaces C sides, sandwiching the side lead-out portion 15Bb.

[0054] The uneven portion 150 of the edge 16BL preferably includes two or more sets of convex portions 151 and concave portions 152 in succession, and in the embodiment, includes two sets in succession.

[0055] The side facing portion 15Ba laterally connected to the internal electrode layer 15B also has, at the edge 16BW along the width direction W, a concave-convex portion 150 including convex portions 151 facing the end surface C adjacent to the edge 16BW and concave portions 152 away from the end surface C alternately.

[0056] To explain in more detail, the edge 16BW includes two convex portions 151 and one concave portion 152 therebetween.

[0057] The concavoconvex portion 150 includes a portion where the concavoconvex difference d is 3 μm or more. The concavoconvex difference d is the difference between the distance x1 from the top of the convex portion 151 to the outer surface and the distance x2 from the bottom of the concave portion 152 adjacent to the convex portion 151 to the outer surface.

[0058] Specifically, the uneven portion 150 provided in at least one edge 16 among the edge 16BL, the edge 16BW, and the edge 16AL includes a portion where the unevenness difference d is 3 μm or more.

[0059] In addition, it is preferable that the uneven portions 150 of all the edges 16 of the edge 16BL, the edge 16BW, and the edge 16AL include a portion where the unevenness difference d is 3 μm or more.

[0060] Furthermore, it is more preferable that the unevenness difference d of all the convex portions 151 and concave portions 152 of all the edges 16 of the edge 16BL, the edge 16BW, and the edge 16AL is 3 μm or more.

[0061] Figure 6 This is a perspective view of the internal electrode layer 15 when viewed from the main surface A. The tip of the arrow shows an enlarged view of the portion P enclosed by the dotted line in the figure. In the embodiment, it is preferred that the positional deviation x3 in the longitudinal direction L of the top of the convex portion 151 in the plurality of internal electrode layers 15 arranged inside the stack 2 is 250 μm or less.

[0062] Figure 7 It is along Figure 6 That is, Figure 7 This is a cross section at a position that passes through the length direction L and the stacking direction T and is farther from the side surface B than the distance from the top of the convex portion 151 to the side surface B and is shorter than the distance from the bottom of the concave portion 152 to the side surface B. In this cross-sectional view, portions Q1 where the exposed portions of the internal electrode layer 15 overlap in the stacking direction T and portions Q2 where the unexposed portions of the internal electrode layer overlap in the stacking direction T are alternately arranged.

[0063] (Outer layer 12)

[0064] Back to Figure 2 as well as Figure 3The outer layer portion 12 is a dielectric layer having a certain thickness and arranged on the main surface A side of the inner layer portion 11. The outer layer portion 12 is made of the same material as the dielectric layer 14 of the inner layer portion 11.

[0065] (End surface external electrode 3)

[0066] End surface external electrodes 3 are arranged on both end surfaces C of the stack 2. End surface lead portions 15Ab of the end surface connection internal electrode layers 15A are connected to the end surface external electrodes 3. The end surface external electrodes 3 cover not only the end surface C but also a portion of the principal surface A and the side surface B on the end surface C side.

[0067] (Side external electrode 4)

[0068] Side external electrodes 4 are arranged on both side surfaces B of the laminate 2. Side lead portions 15Bb of the side connection internal electrode layer 15B are connected to the side external electrodes 4. The side external electrodes 4 cover not only the side surfaces B but also a portion of the side surface B side of the principal surface A.

[0069] The end surface external electrode 3 and the side surface external electrode 4 include a base electrode layer 31 and a plating layer 32 disposed on the base electrode layer 31 . The plating layer 32 includes a Ni (nickel) plating layer 321 disposed on the base electrode layer 31 and a Sn (tin) plating layer 322 disposed on the Ni plating layer 321 .

[0070] (Method for Manufacturing Multilayer Ceramic Capacitor 1)

[0071] Next, a method for manufacturing the multilayer ceramic capacitor 1 according to the embodiment will be described.

[0072] Figure 8 1 is a flowchart for explaining a method for manufacturing the multilayer ceramic capacitor 1 . Fig. 9 The diagrams are for explaining the internal electrode pattern forming step S1 and the laminating step S2 in the method for manufacturing the multilayer ceramic capacitor 1 .

[0073] (Internal Electrode Pattern Forming Step S1)

[0074] First, a side surface connection internal electrode layer pattern 115B that becomes a side surface connection internal electrode layer 15B is formed by a conductive paste on the ceramic green sheet 114 that becomes the dielectric layer 14. Also, an end surface connection internal electrode layer pattern 115A that becomes an end surface connection internal electrode layer 15A is similarly formed by a conductive paste on the first ceramic green sheet 114A that becomes the dielectric layer 14.

[0075] The ceramic green sheet 114 is a strip-shaped sheet obtained by molding a ceramic slurry containing ceramic powder, a binder, and a solvent into a sheet on a carrier film using a die coater, a gravure coater, a micro gravure coater, or the like.

[0076] The end surface connection internal electrode layer pattern 115A and the side surface connection internal electrode layer pattern 115B are formed by printing, for example, screen printing, gravure printing, relief printing, etc. Here, convex portions 151 and concave portions 152 are formed at the edges of the end surface connection internal electrode layer pattern 115A and the side surface connection internal electrode layer pattern 115B.

[0077] As a formation method, when printing is performed on the ceramic green sheet 114, the end surface connection internal electrode layer pattern 115A and the side surface connection internal electrode layer pattern 115B already include the convex portion 151 and the concave portion 152. In addition, for the end surface connection internal electrode layer pattern 115A and the side surface connection internal electrode layer pattern 115B, a pattern that does not include the convex portion 151 and the concave portion 152, that is, a pattern whose edge is a straight line, is printed on the edge 16, and then the convex portion 151 and the concave portion 152 are added to the edge.

[0078] (Lamination process S2)

[0079] The sheets having the end surface connection internal electrode layer pattern 115A and the sheets having the side surface connection internal electrode layer pattern 115B are alternately stacked. Next, the outer layer ceramic green sheet 112 and the stacked sheets are thermally compressed to form a mother block.

[0080] (Master block cutting process S3)

[0081] Next, the mother block is cut in the longitudinal direction L and the width direction W to be divided, thereby producing a plurality of rectangular laminated bodies 2 .

[0082] (External Electrode Forming Step S4)

[0083] Next, end surface external electrodes 3 are formed on both end surfaces C of the stacked body 2, and side surface external electrodes 4 are formed on both side surfaces B of the stacked body 2. The end surface external electrodes 3 are connected to the end surface lead-out portions 15Ab of the end surface connected to the internal electrode layer 15A. The end surface external electrodes 3 are formed to cover not only the end surface C but also the principal surface A and a portion of the end surface C side of the side surface B. The side surface external electrodes 4 are connected to the side surface lead-out portions 15Bb of the side surface connected to the internal electrode layer 15B. The side surface external electrodes 4 are formed to cover not only the side surface B but also a portion of the side surface B side of the principal surface A.

[0084] (Firing process S5)

[0085] Then, the laminate 2 is heated in a nitrogen atmosphere at a set firing temperature for a given time. Thus, the end surface external electrodes 3 are fired on the laminate 2, thereby manufacturing Figure 1 The multilayer ceramic capacitor 1 is shown.

[0086] (Effects of Multilayer Ceramic Capacitor 1 According to Embodiment)

[0087] Fig.10 This is a diagram showing the electric lines generated between the internal electrode layers when there are two internal electrode layers as a general phenomenon. The electric lines generated in the internal electrode layers are drawn into a circle at the edge of the internal electrode layers as shown in the figure. By drawing the electric lines, the dielectric layer around the edge of the internal electrode layer, especially the area not sandwiched by the internal electrode layer, can be polarized, and the capacitor capacity as a stacked ceramic capacitor can be increased by the polarization. Therefore, if the edge of the internal electrode is longer, the polarization area can be increased, so the capacitor capacity as a stacked ceramic capacitor can be further increased.

[0088] The multilayer ceramic capacitor 1 of the embodiment has a concavo-convex portion 150 composed of a convex portion 151 and a concave portion 152 formed on the edge 16 of the internal electrode layer 15. Therefore, the length of the edge 16 of the internal electrode layer 15 can be increased without increasing the area of ​​the internal electrode layer 15, so that the capacitor capacity of the multilayer ceramic capacitor can be increased.

[0089] (Experimental results)

[0090] The laminated ceramic capacitors of Examples 1 to 12 were prepared as the laminated ceramic capacitor 1 of the embodiment and the laminated ceramic capacitors of Comparative Examples 1, 2, and 3. All the laminated ceramic capacitors had a 1209 size (1.2 mm×0.9 mm).

[0091] In the embodiment, a concave-convex portion 150 is provided at any one of an edge 16AL extending in the length direction L of an end surface opposing portion 15Aa of an end surface connected to an internal electrode layer 15A, an edge 16BL extending in the length direction L of a side surface opposing portion 15Ba of a side surface connected to an internal electrode layer 15B, and an edge 16BW extending in the width direction W of an end surface opposing portion 15Aa of an end surface connected to an internal electrode layer 15A. The concave-convex difference d of the distance x2 from the bottom of the convex portion 151 and the adjacent concave portion 152 to the outer surface is substantially equal, which is 3 μm or 6 μm.

[0092] The comparative example does not have the concavo-convex portion 150. When the concavo-convex difference d≦1 μm, it is considered that the concavo-convex portion 150 is not provided.

[0093] Next, the results of measuring the capacitor capacitance of the multilayer ceramic capacitors of the respective examples and comparative examples are shown. Fig.11 , 12 , 13. In addition, Fig.11 , 12 13, the ratio of the increase in the capacitor capacity of the embodiment relative to the capacitor capacity of the comparative example is also shown.

[0094] exist Fig.11In Examples 1, 2, 3, 4 and Comparative Example 1 shown, the total number of laminated internal electrode layers 15 is 492.

[0095] In Example 1, a concavoconvex portion 150 is provided at edge 16AL and edge 16BL. The concavoconvex difference d is 3 μm. In Example 2, a concavoconvex portion 150 is provided at edge 16AL, edge 16BL, and edge 16BW. The concavoconvex difference d is 3 μm. In Example 3, a concavoconvex portion 150 is provided at edge 16AL and edge 16BL. The concavoconvex difference d is 6 μm. In Example 4, a concavoconvex portion 150 is provided at edge 16AL, edge 16BL, and edge 16BW. The concavoconvex difference d is 6 μm. In Comparative Example 1, no concavoconvex portion 150 is provided.

[0096] like Fig.11 As shown, the comparison example 1 and the embodiments 1, 2, 3, and 4 were compared, and the results confirmed that the capacitor capacity was increased by providing the concavo-convex portion 150 on the edge 16. Compared with the comparison example 1, the capacitor capacity of the embodiment 1 increased by 0.5%, the capacitor capacity of the embodiment 2 increased by 0.8%, the capacitor capacity of the embodiment 3 increased by 0.9%, and the capacitor capacity of the embodiment 4 increased by 1.6%.

[0097] Furthermore, Example 1 was compared with Example 2, and Example 3 was compared with Example 4, and the results confirmed that by providing the convex-concave portion 150 not only on the edge 16AL and the edge 16BL extending along the length direction L, but also on the edge 16BW extending along the width direction W, the number of convex-concave portions 150 was increased, thereby increasing the capacitor capacity.

[0098] Furthermore, as a result of comparing Examples 1 and 2 with Examples 3 and 4, it was confirmed that the capacitor capacitance increased when the unevenness difference d was increased from 3 μm to 6 μm.

[0099] exist Fig.12 In Examples 5, 6, 7, 8 and Comparative Example 2 shown, the total number of laminated internal electrode layers 15 is 100.

[0100] In Example 5, a concavo-convex portion 150 is provided at edge 16AL and edge 16BL. The concavo-convex difference d is 3 μm. In Example 6, a concavo-convex portion 150 is provided at edge 16AL, edge 16BL, and edge 16BW. The concavo-convex difference d is 3 μm. In Example 7, a concavo-convex portion 150 is provided at edge 16AL and edge 16BL. The concavo-convex difference d is 6 μm. In Example 8, a concavo-convex portion 150 is provided at edge 16AL, edge 16BL, and edge 16BW. The concavo-convex difference d is 6 μm. In Comparative Example 2, no concavo-convex portion 150 is provided.

[0101] like Fig.12As shown, the comparison example 2 and the embodiments 5, 6, 7, and 8 were compared, and the results confirmed that the capacitor capacity was increased by providing the concave-convex portion 150 on the edge. Compared with the comparison example 2, the capacitor capacity of the embodiment 5 increased by 0.5%, the capacitor capacity of the embodiment 6 increased by 0.8%, the capacitor capacity of the embodiment 7 increased by 0.9%, and the capacitor capacity of the embodiment 8 increased by 1.6%.

[0102] Furthermore, Example 5 was compared with Example 6, and Example 7 was compared with Example 8, and the results confirmed that by providing the convex-concave portion 150 not only on the edge 16AL and the edge 16BL extending along the length direction L, but also on the edge 16BW extending along the width direction W, the number of convex-concave portions 150 was increased, thereby increasing the capacitor capacity.

[0103] Furthermore, as a result of comparing Examples 5 and 6 with Examples 7 and 8, it was confirmed that the capacitor capacitance increased when the unevenness difference d was increased from 3 μm to 6 μm.

[0104] exist Fig.13 In Examples 9, 10, 11, 12 and Comparative Example 3 shown, the total number of laminated internal electrode layers 15 is three.

[0105] Example 9: Concavoconvex portion 150 is provided at edge 16AL and edge 16BL. The concavoconvex difference d is 3 μm. Example 10: Concavoconvex portion 150 is provided at edge 16AL, edge 16BL, and edge 16BW. The concavoconvex difference d is 3 μm. Example 11: Concavoconvex portion 150 is provided at edge 16AL and edge 16BL. The concavoconvex difference d is 6 μm. Example 12: Concavoconvex portion 150 is provided at edge 16AL, edge 16BL, and edge 16BW. The concavoconvex difference d is 6 μm. Comparative Example 3: Concavoconvex portion 150 is not provided.

[0106] like Fig.13 As shown, the comparison example 3 and the embodiments 9, 10, 11, and 12 were compared, and the result confirmed that the capacitor capacity was increased by providing the concave-convex portion 150 on the edge. Compared with the comparison example 3, the capacitor capacity of the embodiment 9 increased by 0.5%, the capacitor capacity of the embodiment 10 increased by 0.8%, the capacitor capacity of the embodiment 11 increased by 0.9%, and the capacitor capacity of the embodiment 12 increased by 1.6%.

[0107] Furthermore, Example 9 was compared with Example 10, and Example 11 was compared with Example 12. The results confirmed that by providing the convex-concave portion 150 not only on the edge 16AL and the edge 16BL extending along the length direction L, but also on the edge 16BW extending along the width direction W, the number of convex-concave portions 150 was increased, thereby increasing the capacitor capacity.

[0108] Furthermore, as a result of comparing Examples 9 and 10 with Examples 11 and 12, it was confirmed that the capacitor capacitance increased when the unevenness difference d was increased from 3 μm to 6 μm.

[0109] Although the embodiment of the present invention has been described above, various modifications are possible within the scope of the present invention. For example, the multilayer ceramic capacitor 1 of the above embodiment alternately arranges the end surface-connected internal electrode layers 15A and the side surface-connected internal electrode layers 15B, but the present invention is not limited to this. Fig.14 1 is an exploded perspective view of a laminated body 2 in a laminated ceramic capacitor according to a modified embodiment of the present invention. As shown in the figure, the laminated ceramic capacitor according to the modified embodiment does not have a side-connected internal electrode layer, and therefore does not have a side external electrode.

[0110] like Fig.14 As shown, the deformed multilayer ceramic capacitor is alternately provided with a first internal electrode layer 215A connected to one end surface external electrode (not shown) and a second internal electrode layer 215B connected to the other end surface external electrode (not shown). Furthermore, a concave-convex portion 150 is provided at the edges of the first internal electrode layer 215A and the second internal electrode layer 215B.

[0111] In the multilayer ceramic capacitor of such a modified form, similarly to the above-mentioned embodiment, the concavo-convex portion 150 composed of the convex portion 151 and the concave portion 152 is formed at the edge of the internal electrode layer 215. Therefore, the length of the edge of the internal electrode layer 215 can be lengthened without increasing the area of ​​the internal electrode layer 215, so that the capacitor capacity as the multilayer ceramic capacitor can be increased.

[0112] Furthermore, as another variation, the concavo-convex portion provided on the edge of the internal electrode layer in the embodiment and the variation is a sinusoidal curved portion, but the present invention is not limited thereto and the concavo-convex portion may be rectangular, sawtooth or triangular.

[0113] As mentioned above, although the preferred embodiment and the modification of this invention were described, it is not limited to these, and this invention includes the following scope.

[0114] <1> A multilayer ceramic capacitor comprising:

[0115] A laminate having internal electrode layers and dielectric layers alternately laminated; and external electrodes respectively arranged on at least one pair of mutually opposing outer surfaces of the laminate extending in the lamination direction,

[0116] The internal electrode layer includes a facing portion where the internal electrode layers adjacent to each other in the stacking direction overlap each other, and a lead portion extending from the facing portion toward the external electrode.

[0117] The edge of the facing portion has a concavo-convex portion that alternately includes convex portions facing the outer surface adjacent to the edge and concave portions away from the outer surface.

[0118] <2> The multilayer ceramic capacitor according to <1>, wherein

[0119] The outer surface includes end surfaces provided at both ends of a length direction intersecting the stacking direction,

[0120] The external electrodes include end surface external electrodes respectively arranged on the end surfaces,

[0121] The internal electrode layer includes an end surface connection internal electrode layer having an end surface lead portion extending toward the end surface external electrode as the lead portion.

[0122] <3> The multilayer ceramic capacitor according to <1> or <2>, wherein:

[0123] The outer surface includes side surfaces provided at both ends in a width direction intersecting the stacking direction,

[0124] The external electrodes include side external electrodes respectively arranged on the side surfaces,

[0125] The internal electrode layer includes a side surface-connected internal electrode layer having a side surface lead portion extending toward the side surface external electrode as the lead portion.

[0126] <4> The multilayer ceramic capacitor according to any one of <1> to <3>, wherein

[0127] The concavo-convex portion of the edge extending in the longitudinal direction intersecting the stacking direction among the edges has a continuous set of two or more convex portions and concave portions.

[0128] <5> The multilayer ceramic capacitor according to any one of <1> to <4>, wherein

[0129] The edge includes a portion where a difference between a distance from the top of the convex portion to the outer surface and a distance from the bottom of the concave portion adjacent to the convex portion to the outer surface is 3 μm or more.

[0130] <6> The multilayer ceramic capacitor according to any one of <1> to <5>, wherein

[0131] When viewed from the main surfaces provided on both sides in the stacking direction, the position deviation of the top portions of the protrusions in the plurality of internal electrode layers arranged inside the stacked body in the longitudinal direction intersecting the stacking direction is 250 μm or less.

[0132] <7> The multilayer ceramic capacitor according to any one of <1> to <6>, wherein

[0133] In a cross-section passing through the length direction intersecting the stacking direction and the stacking direction at a position where the distance from the side surfaces arranged at both ends of the width direction intersecting the stacking direction is longer than the distance from the top of the convex portion to the side surfaces and shorter than the distance from the bottom of the concave portion to the side surfaces, portions of the internal electrode layers that overlap in the stacking direction and portions of the internal electrode layers that do not expose are alternately arranged.

[0134] Description of Reference Numerals

[0135] A main surface;

[0136] B side;

[0137] C end face;

[0138] d Concave-convex difference;

[0139] x3 position offset;

[0140] 1. Multilayer ceramic capacitor;

[0141] 2 laminates;

[0142] 3. End surface external electrode;

[0143] 4 lateral external electrodes;

[0144] 14 dielectric layer;

[0145] 15 internal electrode layer;

[0146] 15A end surface is connected to the internal electrode layer;

[0147] 15Aa end surface facing portion;

[0148] 15Ab end lead-out portion;

[0149] 15B is connected to the inner electrode layer on the side;

[0150] 15Ba lateral opposing portion;

[0151] 15Bb side lead-out;

[0152] 15a: opposing portion;

[0153] 15b lead-out part;

[0154] 16 Edge;

[0155] 16AL Edge;

[0156] 16BL edge;

[0157] 16BW Edge;

[0158] 150 concave and convex parts;

[0159] 151 convex part;

[0160] 152 recess.

Claims

1. A multilayer ceramic capacitor comprising: A laminate having internal electrode layers and dielectric layers alternately laminated; and external electrodes respectively arranged on at least one pair of mutually opposing outer surfaces of the laminate extending in the lamination direction, The internal electrode layer includes a facing portion where the internal electrode layers adjacent to each other in the stacking direction overlap each other, and a lead portion extending from the facing portion toward the external electrode. The edge of the facing portion has a concavo-convex portion that alternately includes convex portions facing the outer surface adjacent to the edge and concave portions away from the outer surface.

2. The multilayer ceramic capacitor according to claim 1, wherein The outer surface includes end surfaces provided at both ends of a length direction intersecting the stacking direction, The external electrodes include end surface external electrodes respectively arranged on the end surfaces, The internal electrode layer includes an end surface connection internal electrode layer having an end surface lead portion extending toward the end surface external electrode as the lead portion.

3. The multilayer ceramic capacitor according to claim 1 or 2, wherein: The outer surface includes side surfaces provided at both ends in a width direction intersecting the stacking direction, The external electrodes include side external electrodes respectively arranged on the side surfaces, The internal electrode layer includes a side surface-connected internal electrode layer having a side surface lead portion extending toward the side surface external electrode as the lead portion.

4. The multilayer ceramic capacitor according to claim 1, wherein The concavo-convex portion of the edge extending in the longitudinal direction intersecting the stacking direction among the edges has a continuous set of two or more convex portions and concave portions.

5. The multilayer ceramic capacitor according to claim 1, wherein The edge includes a portion where a difference between a distance from the top of the convex portion to the outer surface and a distance from the bottom of the concave portion adjacent to the convex portion to the outer surface is 3 μm or more.

6. The multilayer ceramic capacitor according to claim 1, wherein When viewed from the main surfaces provided on both sides in the stacking direction, the position deviation of the top portions of the protrusions in the plurality of internal electrode layers arranged inside the stacked body in the longitudinal direction intersecting the stacking direction is 250 μm or less.

7. The multilayer ceramic capacitor according to claim 1, wherein In a cross-section passing through the length direction intersecting the stacking direction and the stacking direction at a position where the distance from the side surfaces arranged at both ends of the width direction intersecting the stacking direction is longer than the distance from the top of the convex portion to the side surfaces and shorter than the distance from the bottom of the concave portion to the side surfaces, portions of the internal electrode layers that overlap in the stacking direction and portions of the internal electrode layers that do not expose are alternately arranged.

Images