Multilayer ceramic electronic component

Abstract

Provided is a multilayer ceramic electronic component (1) wherein the surface of a multilayer body (2) can be more flattened easily. This multilayer ceramic electronic component (1) is provided with a multilayer body (2) which comprises: first internal electrode layers (10a) that are alternately stacked with a plurality of ceramic layers (4), while being exposed in a first end face (62a); second internal electrode layers (10b) that are alternately stacked with the plurality of ceramic layers (4), while being exposed in a second end face (62b); first level difference layers (5a) which are arranged on the same planes as the second internal electrode layers (10b), while being exposed in the first end face (62a); and second level difference layers (5b) which are arranged on the same planes as the first internal electrode layers (10a), while being exposed in the second end face (62b). The distance between a first level difference layer (5a) and a second internal electrode layer (10b) in the length direction (L) becomes longer as the positions of the first level difference layer (5a) and the second internal electrode layer (10b) are closer to a first main surface (61a); and the distance between a second level difference layer (5b) and a first internal electrode layer (10a) in the length direction (L) becomes longer as the positions of the second level difference layer (5b) and the first internal electrode layer (10a) are closer to the first main surface (61a).

Description

Multilayer ceramic electronic components

[0001] The present invention relates to a multilayer ceramic electronic component, and more particularly to a multilayer ceramic capacitor.

[0002] Multilayer ceramic capacitors have been known as conventional multilayer ceramic electronic components. Generally, multilayer ceramic capacitors have a structure including a laminate, which is a fired body in which multiple ceramic dielectric layers and internal electrode layers are alternately stacked, and external electrodes provided on both end surfaces of the laminate, and have a desired capacitance according to the number of layers and the thickness of the dielectric layers. Patent Document 1 and other publications describe the provision of a step absorption layer to eliminate steps caused by the internal electrode layers.

[0003] Japanese Patent Application Laid-Open No. 2006-286860

[0004] However, in reality, the curvature often tends to be greater toward the first or second principal surface, and the degree of curvature tends to be greater toward the surface away from the curvature. Therefore, if step absorption layers are disposed on the same plane as each internal electrode layer, as described in Patent Document 1, the step absorption layers are also disposed in areas that are only curved to an extent that does not affect structural defects. This poses the problem of the possibility of new structural defects occurring and the increased cost of the step absorption layers. Therefore, the present invention aims to suppress structural defects by reducing costs and disposing appropriate amounts of step absorption layers in appropriate locations.

[0005] The multilayer ceramic electronic component of the present invention includes a plurality of laminated ceramic layers, and includes first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, first end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction, first internal electrode layers alternately laminated with the plurality of ceramic layers and exposed at the first end surfaces, second internal electrode layers alternately laminated with the plurality of ceramic layers and exposed at the second end surfaces, a first step layer disposed on the same plane as the second internal electrode layers and exposed at the first end surfaces, and a laminate including a second step layer disposed on the same plane as a first internal electrode layer and exposed at the second end face; a first external electrode provided at the first end face; and a second external electrode provided at the second end face, wherein the longitudinal distance between the first step layer and the second internal electrode layer is greater when the first step layer is located closer to the first main surface, and the longitudinal distance between the second step layer and the first internal electrode layer is greater when the second step layer is located closer to the first main surface.

[0006] The multilayer ceramic electronic component of the present invention includes a plurality of laminated ceramic layers, and includes first and second main surfaces opposing each other in a height direction, first and second side surfaces opposing each other in a width direction perpendicular to the height direction, first end surfaces opposing each other in a length direction perpendicular to the height direction and the width direction, end-surface-exposed electrode layers that are internal electrode layers laminated alternately with the plurality of ceramic layers and exposed at the first end surfaces and the second end surfaces, side-surface-exposed electrode layers that are internal electrode layers laminated alternately with the plurality of ceramic layers and exposed at the first side surfaces and the second side surfaces, and an electrode layer disposed on the same plane as the end-surface-exposed electrode layers and exposed at the first side surfaces and the second side surfaces. a laminate including an exposed side surface step layer and an end surface step layer arranged on the same plane as the side surface exposed electrode layer and exposed at the first end surface and the second end surface; a first external electrode provided on the first end surface and the second end surface; and a second external electrode provided on the first side surface and the second side surface, wherein the widthwise distance between the side surface step layer and the end surface exposed electrode layer is greater when the side surface step layer is located closer to the first main surface, and the lengthwise distance between the end surface step layer and the side surface exposed electrode layer is greater when the side surface step layer is located closer to the first main surface.

[0007] According to the present invention, it is possible to provide a multilayer ceramic electronic component in which the surface of the laminate can be more easily made flat.

[0008] 1 is a perspective view of a multilayer ceramic electronic component according to a first embodiment of the present invention. It is a cross-sectional view taken along line I-I in FIG. 1. It is a cross-sectional view taken along line II-II in FIG. 1. It is an LT cross-sectional view of a laminate according to the first embodiment. It is an LT cross-sectional view of a laminate according to a second embodiment. It is an LT cross-sectional view of a multilayer ceramic electronic component according to the second embodiment. It is a perspective view of a multilayer ceramic electronic component according to a third embodiment. It is a cross-sectional view taken along line III-III in FIG. 7. It is a cross-sectional view taken along line IV-IV in FIG. 7. It is a cross-sectional view taken along line V-V in FIG. 7, showing the planar structure of an end face-exposed electrode layer. It is a cross-sectional view taken along line V-V in FIG. 7, showing the planar structure of a side face-exposed electrode layer.

[0009] An embodiment of a multilayer ceramic electronic component 1 according to the present invention will now be described with reference to the accompanying drawings. In the following description, the multilayer ceramic electronic component 1 is a multilayer ceramic capacitor.

[0010] (First embodiment) A multilayer ceramic electronic component 1 according to a first embodiment will be described. (External appearance of the multilayer ceramic electronic component) An outline of the external appearance of the multilayer ceramic electronic component 1 will be described with reference to Fig. 1. Fig. 1 is a perspective view showing the multilayer ceramic electronic component 1 according to this embodiment. The multilayer ceramic electronic component 1 includes a laminate 2 and external electrodes 20.

[0011] (Definition of Directions) The drawings appropriately show the L direction, W direction, and T direction. The L direction is the length direction of the multilayer ceramic electronic component 1. The W direction is the width direction of the multilayer ceramic electronic component 1. The T direction is the height direction of the multilayer ceramic electronic component 1. Therefore, the cross section shown in FIG. 2 is called an LT cross section, and the cross section shown in FIG. 3 is called a WT cross section. The length direction L, width direction W, and height direction T do not necessarily have to be orthogonal to each other. The length direction L, width direction W, and height direction T may intersect each other.

[0012] (External Shape of Laminate) The laminate 2 has a substantially rectangular parallelepiped shape. The laminate 2 has two main surfaces 61, two end surfaces 62, and two side surfaces 63. The main surface 61 is a surface facing the height direction T. The end surfaces 62 are surfaces facing the length direction L. The side surfaces 63 are surfaces facing the width direction W. One of the two main surfaces 61 is a first main surface 61a, and the other is a second main surface 61b. One of the two end surfaces 62 is a first end surface 62a, and the other is a second end surface 62b. One of the two side surfaces 63 is a first side surface 63a, and the other is a second side surface 63b. The first main surface 61a and the first side surface 63a are shown in FIG. 1.

[0013] It is preferable that the ridges and corners of the laminate 2 are rounded. A ridge is a portion where two surfaces of the laminate 2 intersect. A corner is a portion where three surfaces of the laminate 2 intersect. The size of the laminate 2 is not particularly limited.

[0014] (Structure of the Laminate) The laminate 2 includes a plurality of ceramic layers 4 and a plurality of internal electrode layers 10. The structure of the laminate 2 will be described below with reference to a cross-sectional view of the laminate 2.

[0015] (Internal Structure of Laminate (LT Cross Section)) The internal structure of the laminate 2 will be described with reference to FIG. 2. FIG. 2 is a cross-sectional view of the multilayer ceramic electronic component 1 shown in FIG. 1 taken along line II. FIG. 2 shows the LT cross section of the multilayer ceramic electronic component 1. The laminate 2 includes a plurality of ceramic layers 4 and a plurality of internal electrode layers 10. The plurality of ceramic layers 4 and the plurality of internal electrode layers 10 are stacked on top of each other in the height direction T.

[0016] (Inner layer portion and outer layer portion) The laminate 2 is divided into an inner layer portion 53 and two outer layer portions 54 in the height direction T. The outer layer portion 54 includes a first outer layer portion 54a and a second outer layer portion 54b. The first outer layer portion 54a and the second outer layer portion 54b are located at positions sandwiching the inner layer portion 53 in the height direction T.

[0017] In the inner layer portion 53, some of the plurality of ceramic layers 4 and a plurality of internal electrode layers 10 are arranged. In the inner layer portion 53, the plurality of internal electrode layers 10 face each other with the ceramic layer 4 interposed therebetween. Therefore, a capacitance is formed in the inner layer portion 53. Therefore, the inner layer portion 53 is a portion of the laminate 2 that essentially functions as a capacitor.

[0018] The first outer layer portion 54a is a portion of the outer layer portion 54 located on the side of the first main surface 61a of the laminate 2. The second outer layer portion 54b is a portion of the outer layer portion 54 located on the side of the second main surface 61b of the laminate 2. Specifically, the first outer layer portion 54a is a portion between the first main surface 61a and an internal electrode layer 10 of the multiple internal electrode layers 10 that is closest to the first main surface 61a. The second outer layer portion 54b is a portion between the second main surface 61b and an internal electrode layer 10 of the multiple internal electrode layers 10 that is closest to the second main surface 61b. No internal electrode layer 10 is arranged in the first outer layer portion 54a and the second outer layer portion 54b. The remaining ceramic layers 4 of the multiple ceramic layers 4, excluding the ceramic layers 4 for the internal layer portion 53, are arranged in the first outer layer portion 54a and the second outer layer portion 54b. The first outer layer portion 54 a and the second outer layer portion 54 b function as protective layers for the inner layer portion 53 .

[0019] (Ceramic Layer) The ceramic layer 4 can be classified into a ceramic layer 4 disposed in the inner layer portion 53 and a ceramic layer 4 disposed in the outer layer portion 54. The ceramic layer 4 disposed in the inner layer portion 53 is referred to as an inner ceramic layer 4a. The ceramic layer 4 disposed in the outer layer portion 54 is referred to as an outer ceramic layer 4b.

[0020] (Number of Ceramic Layers) The number of ceramic layers 4 stacked in the laminate 2 can be, for example, 5 to 2000.

[0021] (Material of Ceramic Layer) The material of the ceramic layer 4 is, for example, BaTiO ３ , CaTiO ３ , SrTiO ３ , CaZrO ３ It is possible to use a dielectric ceramic made of the above-mentioned main components. It is also possible to use a ceramic made by adding a subcomponent such as a Mn compound, an Fe compound, a Cr compound, a Co compound, or a Ni compound to these main components.

[0022] When a piezoelectric ceramic is used for the laminate 2, the multilayer ceramic electronic component 1 functions as a ceramic piezoelectric element. Specific examples of piezoelectric ceramic materials include PZT (lead zirconate titanate) ceramic materials.

[0023] When a semiconducting ceramic is used for the laminate 2, the multilayer ceramic electronic component 1 functions as a thermistor element. Specific examples of semiconducting ceramic materials include spinel ceramic materials.

[0024] When a magnetic ceramic is used for the laminate, the multilayer ceramic electronic component 1 functions as an inductor element. When the multilayer ceramic electronic component 1 functions as an inductor element, the internal electrode layers become coil-shaped conductors. Specific examples of magnetic ceramic materials include ferrite ceramic materials.

[0025] (Thickness of Ceramic Layer) The thickness of the ceramic layer 4 can be set to, for example, 10 μm or less.

[0026] (Internal electrode layers) The internal electrode layers 10 can be classified into first internal electrode layers 10a and second internal electrode layers 10b. The first internal electrode layer 10a is an internal electrode layer 10 connected to the first external electrode 20a. The second internal electrode layer 10b is an internal electrode layer 10 connected to the second external electrode 20b. The first internal electrode layer 10a extends from the first end face 62a toward the second end face 62b. The second internal electrode layer 10b extends from the second end face 62b toward the first end face 62a.

[0027] (Facing portion and extension portion) The first internal electrode layer 10a and the second internal electrode layer 10b each have a facing portion 11 and an extension portion 12. The facing portion 11 is a portion of the internal electrode layer 10 where the first internal electrode layer 10a and the second internal electrode layer 10b face each other in the height direction T. The extension portion 12 is a portion of the internal electrode layer 10 that extends from the facing portion 11 to the first end face 62a or the second end face 62b of the laminate 2.

[0028] The opposing portion 11 of the first internal electrode layer 10a is referred to as the first opposing portion 11a. The extension portion 12 of the first internal electrode layer 10a is referred to as the first extension portion 12a. The first extension portion 12a is a portion that extends from the first opposing portion 11a to the first end face 62a of the laminate 2.

[0029] Similarly, the opposing portion 11 of the second internal electrode layer 10b is referred to as the second opposing portion 11b. The extension portion 12 of the second internal electrode layer 10b is referred to as the second extension portion 12b. The second extension portion 12b is a portion extending from the second opposing portion 11b to the second end face 62b of the laminate 2.

[0030] (Number of Internal Electrode Layers) The number of the internal electrode layers 10 can be, for example, 10 to 2000. The number of the internal electrode layers 10 includes the number of the first internal electrode layers 10a and the number of the second internal electrode layers 10b.

[0031] (Thickness of Internal Electrode Layer) The thickness of the internal electrode layer 10 can be, for example, 0.1 μm or more and 5.0 μm or less, preferably 0.2 μm or more and 2.0 μm or less. When the thickness of the internal electrode layer 10 is 0.5 μm or more, a plating film is likely to grow when the metal layer of the external electrode 20 is formed by plating.

[0032] (Material of the internal electrode layer) The material of the internal electrode layer 10 can be, for example, metals such as Ni, Cu, Ag, Pd, and Au, alloys of Ni and Cu, alloys of Ag and Pd, etc. In addition, the material of the internal electrode layer 10 may contain dielectric particles of the same composition as the ceramic contained in the ceramic layer 4.

[0033] (Electrode Opposing Portion) The following describes the division of the laminate 2 in the longitudinal direction L. The laminate 2 can be divided into an electrode opposing portion 50 and an L gap 51 in the longitudinal direction L. The electrode opposing portion 50 in the division in the longitudinal direction L is referred to as an L opposing portion 50a. The L gap 51 includes a first L gap 51a and a second L gap 51b.

[0034] The L-facing portion 50a corresponds to a portion where the first internal electrode layer 10a and the second internal electrode layer 10b face each other in the height direction T. A capacitance is formed in the L-facing portion 50a.

[0035] (L Gaps) The L gaps 51 are portions in the length direction L of the laminate 2 where the first internal electrode layers 10a and the second internal electrode layers 10b do not face each other in the height direction T. Of the L gaps 51, the first L gap 51a is between the L opposing portion 50a and the first end face 62a. The second L gap 51b is between the L opposing portion 50a and the second end face 62b.

[0036] In the first L gap 51a, the first internal electrode layer 10a is arranged but the second internal electrode layer 10b is not arranged in the height direction T. In the second L gap 51b, the second internal electrode layer 10b is arranged but the first internal electrode layer 10a is not arranged in the height direction T.

[0037] The first L-gap 51a functions as an extension to the first end surface 62a of the first opposing portion 11a, and the second L-gap 51b functions as an extension to the second end surface 62b of the second opposing portion 11b.

[0038] The length of the L gap 51 in the longitudinal direction L can be, for example, 10% or more and 30% or less of the length of the laminate 2 in the longitudinal direction L.

[0039] (External Electrodes) The external electrodes 20 include a first external electrode 20a and a second external electrode 20b. (First External Electrode) The first external electrode 20a is an external electrode 20 arranged on a first end surface 62a of the laminate 2. The first external electrode 20a is electrically connected to the first internal electrode layer 10a. (Second External Electrode) The second external electrode 20b is an external electrode 20 arranged on a second end surface 62b of the laminate 2. The second external electrode 20b is electrically connected to the second internal electrode layer 10b.

[0040] (External Electrode on Each Surface) The external electrode 20 extends from one end surface 62 to parts of the two main surfaces 61 and to parts of the two side surfaces 63 .

[0041] (Layer Structure of External Electrode) The layer structure of the external electrode 20 will be described with reference to Fig. 2. The external electrode 20 includes an underlayer 21 and a plating layer 23. The plating layer 23 includes an inner plating layer 23a and a surface plating layer 23b. These layers are arranged in this order from the end surface 62 of the laminate 2: underlayer 21, inner plating layer 23a, surface plating layer 23b.

[0042] (Underlayer) The underlayer 21 is disposed on the end surface 62 of the laminate 2 and covers the end surface 62. The underlayer 21 extends from the end surface 62 to a part of the main surface 61 and a part of the side surface 63.

[0043] (Baking Layer) The base layer 21 is configured as a baking layer. The baking layer contains a glass component and a metal. The glass component contains at least one selected from B, Si, Ba, Mg, Al, Li, etc. The metal contains at least one selected from Cu, Ni, Ag, Pd, Ag-Pd alloy, Au, etc. The baking layer may be a multi-layered layer.

[0044] (Plating Layer) The plating layer 23 on the base layer 21 will be described. As described above, in this embodiment, the plating layer 23 includes an inner plating layer 23a and a surface plating layer 23b. When the plating layer 23 is a two-layer structure, it is preferable that the plating layers are, from the bottom, a Ni plating layer and a Sn plating layer. That is, the inner plating layer 23a is a Ni plating layer, and the surface plating layer 23b is a Sn plating layer. When the plating layer is a three-layer structure, it is preferable that the plating layers are, from the bottom, a Sn plating layer, a Ni plating layer, and a Sn plating layer.

[0045] The Ni plating layer can prevent the underlayer 21 from being eroded by solder when mounting the multilayer ceramic electronic component 1. The Sn plating layer can improve the wettability of the solder when mounting the multilayer ceramic electronic component 1, facilitating mounting. Therefore, by using an Sn plating layer as the top plating layer 23b, the wettability of the solder to the external electrodes 20 can be improved. The thickness of each plating layer is preferably 3 μm or more and 9 μm or less.

[0046] (Internal Structure of Laminate (WT Cross Section)) The internal structure of the laminate 2 will be described with reference to FIG. 3. FIG. 3 is a cross-sectional view of the multilayer ceramic electronic component 1 shown in FIG. 1 taken along line II-II. The laminate 2 is divided into an electrode opposing portion 50 and a W gap 52 in the width direction W. The electrode opposing portion 50 in the section in the width direction W is referred to as a W opposing portion 50b. The W gap 52 includes a first W gap 52a and a second W gap 52b.

[0047] The W opposing portion 50b is a portion where the internal electrode layers 10 oppose each other in the height direction T. The W gap 52 is a portion where neither the first internal electrode layer 10a nor the second internal electrode layer 10b is disposed in the height direction T in the width direction W.

[0048] Of the W gaps 52, the first W gap 52a is between the W opposing portion 50b and the first side surface 63a in the width direction W of the laminate 2. The second W gap 52b is between the W opposing portion 50b and the second side surface 63b.

[0049] The first W gap 52a and the second W gap 52b are arranged to sandwich the W opposing portion 50b. The first W gap 52a and the second W gap 52b function as protective layers for the internal electrode layer 10.

[0050] The length of the W gap 52 in the width direction W can be, for example, 20% to 30% of the length of the width direction W of the laminate 2. Furthermore, the length of the W gap 52 in the width direction W can be, for example, 5 μm to 50 μm.

[0051] (Size of Multilayer Ceramic Electronic Component) The size of the multilayer ceramic electronic component 1 is not particularly limited. The size of the multilayer ceramic electronic component 1 can be, for example, as follows. The dimension in the length direction L of the multilayer ceramic electronic component 1, including the laminate 2 and the external electrodes 20, is defined as the L dimension. The L dimension is preferably 0.25 mm or more and 1.0 mm or less. The dimension in the height direction T of the multilayer ceramic electronic component 1, including the laminate 2 and the external electrodes 20, is defined as the T dimension. The T dimension is preferably 0.125 mm or more and 0.5 mm or less. The dimension in the width direction W of the multilayer ceramic electronic component 1, including the laminate 2 and the external electrodes 20, is defined as the W dimension. The W dimension is preferably 0.125 mm or more and 0.5 mm or less.

[0052] (Step Layer) The multilayer ceramic electronic component 1 of this embodiment is provided with a step layer 5. It is preferable that the difference in length in the height direction T of the laminate 2 be small between the electrode opposing portion 50 and the L gap 51. However, in the inner layer portion 53, the length in the height direction T tends to differ between the electrode opposing portion 50 and the L gap 51. The ceramic layers 4 and the internal electrode layers 10 are stacked in the electrode opposing portion 50. In contrast, only the ceramic layers 4 are stacked in the L gap 51. No internal electrode layers 10 are stacked in the L gap 51. Therefore, the length in the height direction T tends to differ between the electrode opposing portion 50 and the L gap 51.

[0053] Therefore, in order to reduce the difference in length in the height direction T between the electrode opposing portion 50 and the L gap 51, an additional ceramic layer 4 is disposed in the L gap 51. This additional ceramic layer 4 is referred to as a step layer 5. The step layer 5 preferably has the same components as the ceramic layer 4. However, the components of the ceramic layer 4 are not limited to this.

[0054] (Arrangement of Step Layers) The arrangement of the step layers 5 in the multilayer ceramic electronic component 1 of this embodiment will be described with reference to Fig. 4. Fig. 4 is an LT cross-sectional view of the laminate 2 provided in the multilayer ceramic electronic component 1 of this embodiment. Fig. 4 shows a cross-section of the laminate 2 at a position corresponding to line II in Fig. 1. The step layers 5 are arranged between the ends E of the internal electrode layers 10 in the length direction L and the end faces 62. The step layers 5 include a first step layer 5a and a second step layer 5b.

[0055] (First Step Layer) The first step layer 5a is a step layer 5 arranged on the same plane as the second internal electrode layer 10b. The tip E of the second internal electrode layer 10b on the first end face 62a side in the longitudinal direction L is defined as the tip E1. The first step layer 5a is arranged between the tip E1 and the first end face 62a in the longitudinal direction L. The first step layer 5a is exposed from the first end face 62a.

[0056] (Second Step Layer) The second step layer 5b is a step layer 5 arranged on the same plane as the first internal electrode layer 10a. The tip E of the first internal electrode layer 10a on the second end face 62b side in the length direction L is defined as the tip E2. The second step layer 5b is arranged between the tip E2 and the second end face 62b in the length direction L. The second step layer 5b is exposed from the second end face 62b.

[0057] As described above, a plurality of internal electrode layers 10 are stacked in the laminate 2. The first step layer 5a and the second step layer 5b can be disposed for each internal electrode layer 10. Therefore, a plurality of first step layers 5a and a plurality of second step layers 5b are disposed in one laminate 2. Note that FIG. 4 illustrates two first step layers 5a and two second step layers 5b. This is because FIG. 4 is a schematic diagram for explanation. Therefore, FIG. 4 does not mean that the number of layers of a multilayer ceramic capacitor is limited to the number of layers illustrated in FIG. 4.

[0058] (Thickness of Step Layer) The length of the step layer 5 in the height direction T is defined as the thickness of the step layer 5. (Change in Thickness) Among the multiple first step layers 5a, the thickness of the first step layer 5a located closer to the first main surface 61a is greater than the thickness of the first step layer 5a located closer to the second main surface 61b. The same applies to the second step layer 5b. Among the multiple second step layers 5b, the thickness of the second step layer 5b located closer to the first main surface 61a is greater than the thickness of the second step layer 5b located closer to the second main surface 61b.

[0059] The thickness of the step layer 5 is shown as H in Fig. 4. Two first step layers 5a and two second step layers 5b are shown in Fig. 4. For the two first step layers 5a, the thickness of the first step layer 5a closer to the first main surface 61a is shown as H2, and the thickness of the first step layer 5a closer to the second main surface 61b is shown as H4. Thickness H2 is thicker than thickness H4.

[0060] The same applies to the second step layer 5b. For the two second step layers 5b, the thickness of the second step layer 5b closer to the first main surface 61a is defined as H1, and the thickness of the second step layer 5b closer to the second main surface 61b is defined as H3. Thickness H1 is thicker than thickness H3.

[0061] As described above, in the multilayer ceramic electronic component 1 of this embodiment, the thickness in the height direction T of the ceramic layers 4 between the internal electrode layers 10 connected to the same external electrode 20 increases toward the first main surface 61 a.

[0062] When fabricating the laminate 2, curvature of each layer due to the presence or absence of the internal electrode layers 10 is more likely to occur at the end of lamination than at the beginning of lamination. In other words, the influence of steps due to the presence or absence of the internal electrode layers 10 is greater at the end of lamination. Here, the start of lamination corresponds to the second main surface 61b side. The end of lamination corresponds to the first main surface 61a side. In the multilayer ceramic electronic component 1 of this embodiment, a thicker step layer 5 is provided at the end of lamination. This allows the multilayer ceramic electronic component 1 to reduce the degree of curvature of the laminate 2.

[0063] It is also possible not to form the step layer 5 at the beginning of stacking. That is, the step layer 5 can be formed partially in a part of the stacked body 2 in the height direction T. This makes it possible to more effectively prevent steps from occurring in the stacked body 2.

[0064] (Comparison with Internal Electrode Layers) Next, the relationship between the thickness H of the step layer 5 and the thickness of the internal electrode layer 10 will be described. In FIG. 4, the thickness of the internal electrode layer 10 is indicated as H. In this embodiment, the thickness H of the step layer 5 is 20% to 120% of the thickness K of the internal electrode layer 10. Specifically, the thickness of the first step layer 5a is 20% to 120% of the thickness of the second internal electrode layer 10b. Similarly, the thickness of the second step layer 5b is 20% to 120% of the thickness of the first internal electrode layer 10a. In the example shown in FIG. 4, the thicknesses of the two first step layers 5a are thickness H2 and thickness H4. Also, in FIG. 4, the thickness of the second internal electrode layer 10b is indicated as K2. The thickness H2 and thickness H4 are 20% to 120% of the thickness K2. The same applies to the second step layer 5b. The thicknesses of the two second step layers 5b shown in Fig. 4 are thickness H1 and thickness H3. The thickness of the first internal electrode layer 10a is also shown as K1 in Fig. 4. The thicknesses H1 and H3 are 20% to 120% of the thickness K1.

[0065] (Length Direction Arrangement) So far, the configuration of the step layer 5 in the height direction T has been described. Next, the arrangement of the step layer 5 in the length direction L will be described. (End Face Side) The step layer 5 is exposed from the end face 62. Specifically, the first step layer 5a is exposed at the first end face 62a. Furthermore, the second step layer 5b is exposed at the second end face 62b.

[0066] (Internal electrode side) The end of the step layer 5 opposite to the end exposed from the end face 62 in the longitudinal direction L is in contact with the internal electrode layer 10 in the same layer as the step layer 5 at the tip E of the internal electrode layer 10. The tip E of the internal electrode layer 10 means the end of the internal electrode layer 10 opposite to the end exposed from the end face 62 in the longitudinal direction L. The tip E on the first end face 62a side of the second internal electrode layer 10b is referred to as tip E1. The first step layer 5a is in contact with the second internal electrode layer 10b at the tip E1 of the second internal electrode layer 10b. Similarly, the tip E on the second end face 62b side of the first internal electrode layer 10a is referred to as tip E2. The second step layer 5b is in contact with the first internal electrode layer 10a at the tip E2 of the first internal electrode layer 10a.

[0067] (L-direction end portion) The L-direction end portion 47 refers to a region from the L-direction end portion of the internal electrode layer 10 to the end face 62 to which the internal electrode layer 10 is connected, which is 0 μm to 60 μm in length. That is, D1 shown in FIG. 4 is 0 μm to 60 μm in length.

[0068] Here, the thickness of the ceramic layer 4 and the step layer 5 between the first internal electrode layer 10a and the first internal electrode layer 10a on the adjacent first main surface 61a side is defined as D2. Also, the thickness of the ceramic layer 4 and the step layer 5 between the first internal electrode layer 10a and the first internal electrode layer 10a on the adjacent second main surface 61b side is defined as D3. D2 is larger than D3. D2 increases as it approaches the first main surface side.

[0069] (Coverage) The coverage of the internal electrode layer 10 will be described. The coverage at the L-direction end 47 of the internal electrode layer 10 is lower than the coverage at the opposing portion 11 of the internal electrode layer 10. Specifically, the coverage at the L-direction end 47 of the first internal electrode layer 10a is lower than the coverage at the first opposing portion 11a of the first internal electrode layer 10a. The same is true for the second internal electrode layer 10b, where the coverage at the L-direction end 47 of the second internal electrode layer 10b is lower than the coverage at the second opposing portion 11b of the second internal electrode layer 10b.

[0070] Second Embodiment A second embodiment of the multilayer ceramic electronic component 1 of the present invention will be described with reference to FIGS. 5 and 6. FIG. 5 is an LT cross-sectional view of a laminate 2 in the second embodiment. FIG. 5 is a view corresponding to FIG. 4 in the first embodiment. FIG. 6 is an LT cross-sectional view of a portion of the multilayer ceramic electronic component 1 in the second embodiment. The following description will focus on differences from the first embodiment. In the first embodiment, as shown in FIG. 4, the length of the step layer 5 in the height direction T differs depending on the internal electrode layer 10. In contrast, in the second embodiment, as shown in FIG. 5, the length of the step layer 5 in the length direction L differs depending on the internal electrode layer 10.

[0071] (Distance between step layer and internal electrode layer) The distance in the length direction L between the step layer 5 and the internal electrode layer 10 will be described. Of the two ends of the step layer 5 in the length direction L, the end that is not exposed at the end face 62 is defined as the inner end Q of the step layer 5. The distance in the length direction L between the tip E of the internal electrode layer 10 and the inner end Q of the step layer 5 arranged in the same layer as the internal electrode layer 10 is defined as J. This distance J is the distance in the length direction L between the step layer 5 and the internal electrode layer 10.

[0072] The distance J in the length direction L between the step layer 5 and the internal electrode layer 10 becomes greater as the internal electrode layer 10 is located closer to the first main surface 61a. Specifically, the distance J in the length direction L between the first step layer 5a and the second internal electrode layer 10b is greater when the first step layer 5a is located closer to the first main surface 61a. Similarly, the distance J in the length direction L between the second step layer 5b and the first internal electrode layer 10a is greater when the second step layer 5b is located closer to the first main surface 61a.

[0073] 5 shows two first step layers 5a and two second step layers 5b. For the two first step layers 5a, the distance J in the length direction L between the first step layer 5a and the second internal electrode layer 10b is set to distance J2 for the first step layer 5a closer to the first main surface 61a, and distance J4 for the first step layer 5a closer to the second main surface 61b. Distance J2 is greater than distance J4.

[0074] The same applies to the second step layer 5b. For the two second step layers 5b, the distance J in the longitudinal direction L between the second step layer 5b and the first internal electrode layer 10a is set to distance J1 for the second step layer 5b closer to the first main surface 61a, and to distance J3 for the second step layer 5b closer to the second main surface 61b. Distance J1 is greater than distance J3.

[0075] As described above, in the multilayer ceramic electronic component 1 of this preferred embodiment, the length of the step layer 5 decreases toward the first main surface 61a.

[0076] When fabricating the laminate 2, curvature of each layer due to the presence or absence of the internal electrode layers 10 is more likely to occur at the end of lamination than at the beginning. In other words, the influence of steps due to the presence or absence of the internal electrode layers 10 is greater at the end of lamination. Furthermore, at the end of lamination, the bending of each layer begins closer to the end face. In the multilayer ceramic electronic component 1 of this embodiment, the length of the step layer 5 from the end face 62 is shorter at the end of lamination. This allows the multilayer ceramic electronic component 1 to reduce the degree of curvature of the laminate 2. Furthermore, overlap between the internal electrode layers 10 and the step layers 5 in the height direction T is suppressed, thereby improving the reliability of the multilayer ceramic electronic component 1.

[0077] (Length Ratio to L Gap) The ratio of the lengths of the step layer 5 and the L gap 51 in the longitudinal direction L will be described. In FIG. 5 , the length of the step layer 5 in the longitudinal direction L is indicated by S. Furthermore, the length of the L gap 51 in the longitudinal direction L is indicated by D5. The length S of the step layer 5 is 20% or more of the length D5 of the L gap 51. Specifically, the length S of the first step layer 5a in the longitudinal direction L is 20% or more of the distance in the longitudinal direction L between the tip E1 of the second internal electrode layer 10b and the first end face 62a, i.e., the length D5 of the first L gap 51a in the longitudinal direction L. Similarly, the length S of the second step layer 5b in the longitudinal direction L is 20% or more of the distance in the longitudinal direction L between the tip E2 of the first internal electrode layer 10a and the second end face 62b, i.e., the length D5 of the second L gap 51b.

[0078] 5 shows two first step layers 5a and two second step layers 5b. The length S in the longitudinal direction L of the two first step layers 5a is defined as length S2 for the first step layer 5a closer to the first main surface 61a, and as length S4 for the first step layer 5a closer to the second main surface 61b. Both length S2 and length S4 are 20% or more of the length D5 in the longitudinal direction L of the first L gap 51a.

[0079] The same applies to the second step layer 5b. Regarding the two second step layers 5b, the length S in the longitudinal direction L is defined as length S1 for the second step layer 5b closer to the first main surface 61a, and length S3 for the second step layer 5b closer to the second main surface 61b. Both length S1 and length S3 are 20% or more of the length D5 in the longitudinal direction L of the second L gap 51b.

[0080] (Bent portion) The bent portion 40 of the internal electrode layer 10 will be described with reference to Fig. 6. Fig. 6 is an LT cross-sectional view of a portion of the multilayer ceramic electronic component 1 of the second embodiment. Fig. 6 shows the first L gap 51a of the multilayer ceramic electronic component 1 and the like. The internal electrode layer 10 in the second embodiment has a bent portion 40. The bent portion 40 refers to a portion in the extension portion 12 of the internal electrode layer 10 where the internal electrode layer 10 is bent in the direction of the second main surface 61b.

[0081] Fig. 6 shows the bent portions 40 of the first internal electrode layer 10a. Five bent portions 40 are shown in Fig. 6. The five bent portions 40 are numbered 41 to 45 in order from the first main surface 61a to the second main surface 61b.

[0082] (Starting point of bending) The starting point of bending of the bent portion 40 is defined as point F, and the ending point of bending is defined as point G. The starting point of bending is the point at which the internal electrode layer 10a starts to bend in the direction of the second main surface 61b in the extension portion 12. In Fig. 6, the points F, which are the starting points of bending for each bent portion 40, are shown as points F1 to F5.

[0083] (End points of bending) The end points of bending are points where the bent portions 40 of the internal electrode layers 10 contact the end faces 62. In the configuration shown in Fig. 6, the end points of bending are points where the first internal electrode layers 10a contact the first end faces 62a. In Fig. 6, points G, which are end points of bending for each bent portion 40, are shown as points G1 to G5.

[0084] (Length of bent portion) The length M of the bent portion 40 will be described. The length M of the bent portion 40 is the distance in the longitudinal direction L between the start point G of the bend and the end point G of the bend. In Fig. 6, the length M of each bent portion 40 is shown as length M1 to length M5. The length M of the bent portion 40 becomes shorter as the internal electrode layer 10 is positioned closer to the second main surface 61b. That is, the length M becomes shorter in the order of length M1 to length M5.

[0085] (Height of bent portion) The height N of the bent portion 40 will be described. The height N of the bent portion 40 is the distance in the height direction T between the start point G of the bend and the end point G of the bend. In Fig. 6, the height N of each bent portion 40 is shown as a length N5 from a height N1. The height N of the bent portion 40 becomes lower as the internal electrode layer 10 is positioned closer to the second main surface 61b. That is, the height N becomes lower in the order from height N1 to height N5.

[0086] Third Embodiment A third embodiment of the multilayer ceramic electronic component 1 of the present invention will be described with reference to FIGS. 7 to 11 . The following description will focus on differences from the first and second embodiments. In the first and second embodiments, the multilayer ceramic electronic component 1 is a two-terminal multilayer ceramic capacitor. However, the multilayer ceramic electronic component 1 is not limited to a two-terminal multilayer ceramic capacitor. The multilayer ceramic electronic component 1 can also be a multi-terminal multilayer ceramic capacitor with three or more terminals. In the third embodiment, the multilayer ceramic electronic component 1 is a three-terminal multilayer ceramic capacitor.

[0087] (Outline of Multilayer Ceramic Electronic Component) An outline of the structure of the multilayer ceramic electronic component 1 will be described with reference to FIG. 7 . FIG. 7 is a perspective view showing the multilayer ceramic electronic component 1 of this embodiment. As shown in FIG. 7 , the multilayer ceramic electronic component 1 of this embodiment has external electrodes 20 formed on two side surfaces 63 in addition to two end surfaces 62. The external electrodes 20 formed on the side surfaces 63 are referred to as side surface external electrodes 30. The side surface external electrodes 30 include a first side surface external electrode 30a and a second side surface external electrode 30b. The first side surface external electrode 30a is formed on the first side surface 63a. The second side surface external electrode 30b is formed on the second side surface 63b. In the multilayer ceramic electronic component 1 of this embodiment, the internal electrode layers 10 and the external electrodes 20 can be connected on the two side surfaces 63 in addition to the two end surfaces 62.

[0088] (LT Cross-Section Layers) The LT cross section of the multilayer ceramic electronic component 1 will be described with reference to FIG. 8 . FIG. 8 is a cross-sectional view taken along line III-III in FIG. 7 . As shown in FIG. 8 , a plurality of end-face-exposed electrode layers 10c and a plurality of side-face-exposed electrode layers 10d are stacked in the multilayer body 2, with the inner ceramic layers 4a interposed therebetween. The end-face-exposed electrode layer 10c is connected to the first external electrode 20a at the first end face 62a. The end-face-exposed electrode layer 10c is connected to the second external electrode 20b at the second end face 62b. On the other hand, the side-face-exposed electrode layer 10d is not connected to the external electrode 20 at any of the end faces 62. In a three-terminal multilayer ceramic capacitor, the end-face-exposed electrode layer 10c functions as a through electrode. The side-face-exposed electrode layer 10d functions as a ground electrode.

[0089] (WT Cross-Section Layer) The WT cross section of the multilayer ceramic electronic component 1 will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view taken along line IV-IV in Fig. 7. As shown in Fig. 9, the side surface-exposed electrode layer 10d is connected to the first side surface external electrode 30a at the first side surface 63a. The side surface-exposed electrode layer 10d is connected to the second side surface external electrode 30b at the second side surface 63b. On the other hand, the end surface-exposed electrode layer 10c is not connected to the external electrode 20 at any of the side surfaces 63.

[0090] (Planar Structure of Internal Electrode Layers) The planar structures of the end-face-exposed electrode layer 10c and the side-face-exposed electrode layer 10d will be described with reference to FIGS. 10 and 11. Here, the planar structure refers to the structure of the internal electrode layer 10 when viewed from the height direction T of the multilayer ceramic electronic component 1. (End-face-exposed electrode layer) The end-face-exposed electrode layer 10c will be described with reference to FIG. 10. FIG. 10 is a cross-sectional view taken along line V-V in FIG. 7. FIG. 10 shows the planar structure of the end-face-exposed electrode layer 10c. A first end-face extension 12c is provided in the portion of the end-face-exposed electrode layer 10c exposed at the first end face 62a. Furthermore, a second end-face extension 12d is provided in the portion of the end-face-exposed electrode layer 10c exposed at the second end face 62b. The opposing portion 11 of the end-face-exposed electrode layer 10c is connected to the first end face 62a via the first end-face extension 12c. 10, the facing portion 11 of the end surface exposed electrode layer 10c is connected to the second end surface 62b via the second end surface extension 12d. Although the end surface exposed electrode layer 10c is shown as having a rectangular shape in FIG. 10, the facing portion 11 and the end surface vertical portion, i.e., the first end surface extension 12c and the second end surface extension 12d, may have the same width in the width direction W.

[0091] (Side Surface Exposed Electrode Layer) The side surface exposed electrode layer 10d will be described with reference to FIG. 11. FIG. 11 is a cross-sectional view taken along line V-V in FIG. 7. FIG. 11 shows the planar structure of the side surface exposed electrode layer 10d. A first side surface extension 12e is provided in the portion of the side surface exposed electrode layer 10d that is exposed on the first side surface 63a. A second side surface extension 12f is provided in the portion of the side surface exposed electrode layer 10d that is exposed on the second side surface 63b. The opposing portion 11 of the side surface exposed electrode layer 10d is connected to the first side surface 63a via the first side surface extension 12e. The opposing portion 11 of the side surface exposed electrode layer 10d is connected to the second side surface 63b via the second side surface extension 12f.

[0092] (Definition of Regions) A region of the end-surface exposed electrode layer 10c corresponding to a region where the first side-surface extension 12e is provided on the side-surface exposed electrode layer 10d is defined as a third W gap 52c. Similarly, a region of the end-surface exposed electrode layer 10c corresponding to a region where the second side-surface extension 12f is provided on the side-surface exposed electrode layer 10d is defined as a fourth W gap 52d.

[0093] The region of the side surface exposed electrode layer 10d corresponding to the region where the first end surface extension 12c is provided on the end surface exposed electrode layer 10c is defined as a third L gap 51c. Similarly, the region of the side surface exposed electrode layer 10d corresponding to the region where the second end surface extension 12d is provided on the end surface exposed electrode layer 10c is defined as a fourth L gap 51d.

[0094] In the longitudinal direction L of the laminate 2, the extension region 55 in which the first side extension portion 12e is provided is referred to as a first L-shaped extension region 55c. Similarly, in the longitudinal direction L of the laminate 2, the extension region 55 in which the second side extension portion 12f is provided is referred to as a second L-shaped extension region 55d.

[0095] In addition, the extension region 55 in which the first end face extension portion 12c is provided in the width direction W of the laminate 2 is referred to as a first W extension region 55a. Similarly, in the width direction W of the laminate 2, the extension region 55 in which the second end face extension portion 12d is provided is referred to as a second W extension region 55b.

[0096] (Step Layer) Even when the multilayer ceramic electronic component 1 is a three-terminal multilayer ceramic capacitor, a step layer 5 is disposed in the same manner as in the case of a two-terminal multilayer ceramic capacitor. By appropriately disposing the step layer 5, it is possible to suppress unevenness in the thickness of the laminate 2 in the height direction T caused by the first end face extension 12 c, the second end face extension 12 d, the first side face extension 12 e, and the second side face extension 12 f.

[0097] (End Surface Step Layer) In this embodiment, the step layer 5 includes an end surface step layer 5c and a side surface step layer 5d. The end surface step layer 5c can be used to eliminate steps caused by the first end surface extension 12c and the second end surface extension 12d of the end surface exposed electrode layer 10c. The side surface exposed electrode layer 10d does not have electrodes at positions corresponding to the first end surface extension 12c and the second end surface extension 12d. Therefore, the end surface step layer 5c is disposed in the same layer as the side surface exposed electrode layer 10d at positions corresponding to the first end surface extension 12c and the second end surface extension 12d. This makes it possible to suppress non-uniformity in the height direction T of the stack 2.

[0098] In the same layer as the side surface exposed electrode layer 10d, it is preferable to dispose the end surface step layer 5c in the following two areas. One is the portion in FIG. 11 where the third L gap 51c and the first W extension region 55a overlap. The end surface step layer 5c disposed in this portion reduces unevenness in height caused by the side surface exposed electrode layer 10d not having the first end surface extension 12c. The other is the portion in FIG. 11 where the fourth L gap 51d and the second W extension region 55b overlap. The end surface step layer 5c disposed in this portion reduces unevenness in height caused by the side surface exposed electrode layer 10d not having the second end surface extension 12d.

[0099] (Side Step Layer) Next, the side step layer 5d will be described. The side step layer 5d can be used to eliminate steps caused by the first side extension 12e and the second side extension 12f of the side-exposed electrode layer 10d. The end-exposed electrode layer 10c does not have electrodes at positions corresponding to the first side extension 12e and the second side extension 12f. Therefore, the side step layer 5d is disposed in the same layer as the end-exposed electrode layer 10c, at positions corresponding to the first side extension 12e and the second side extension 12f. This makes it possible to suppress non-uniformity in the height direction T of the laminate 2.

[0100] In the same layer as the end-exposed electrode layer 10c, it is preferable to dispose the side surface step layer 5d in the following two regions. One is the portion in FIG. 10 where the third W gap 52c and the first L-extension region 55c overlap. The side surface step layer 5d disposed in this portion reduces unevenness in height caused by the end-exposed electrode layer 10c not having the first side surface extension 12e. The other is the portion in FIG. 10 where the fourth W gap 52d and the second L-extension region 55d overlap. The side surface step layer 5d disposed in this portion reduces unevenness in height caused by the end-exposed electrode layer 10c not having the second side surface extension 12f.

[0101] The end surface step layer 5c and the side surface step layer 5d can be arranged in the same manner as the first step layer 5a and the second step layer 5b described in the first and second embodiments. In the first and second embodiments, the form of the step layer 5 has been described using the vicinity of the end surface 62 as an example. The form of the step layer 5 described based on this end surface 62 applies not only to the end surface step layer 5c of the third embodiment, but also to the side surface step layer 5d.

[0102] Furthermore, the side surface step layer 5d can be provided in the same layer as the side surface exposed electrode layer 10d. When the side surface step layer 5d is provided in the same layer as the side surface exposed electrode layer 10d, the distance between the electrode layer 10 and the step layer 5 can be the distance in the length direction L between the adjacent side surface extensions 12e, 12f and the side surface step layer 5d. Furthermore, the distance between the electrode layer 10 and the step layer 5 can be the distance in the width direction W between the adjacent opposing portion 11 with the side surface exposed electrode layer 10d and the side surface step layer 5d.

[0103] Similarly, the edge surface step layer 5c can be provided on the same layer as the edge surface exposed electrode layer 10c. When the edge surface step layer 5c is provided on the same layer as the edge surface exposed electrode layer 10c, the distance between the electrode layer 10 and the step layer 5 can be the distance in the length direction L between the adjacent facing portion 11 of the edge surface exposed electrode layer 10c and the edge surface step layer 5c. Furthermore, the distance between the electrode layer 10 and the step layer 5 can be the distance in the width direction W between the adjacent end surface extension portions 12c, 12d and the edge surface step layer 5c.

[0104] (Combination of Embodiments) The above-described embodiments can also be combined. In the first embodiment, the thickness of the step layer 5 in the height direction T has been mainly described. On the other hand, in the second embodiment, the length of the step layer 5 in the length direction T has been mainly described. For example, the thickness of the step layer 5 in the height direction T can be the same as in the first embodiment, and the length of the step layer 5 in the length direction T can be the same as in the second embodiment.

[0105] As described above, in the third embodiment, the step layer 5 of the first or second embodiment may be applied to at least one of the end surface exposed electrode layer 10c and the side surface exposed electrode layer 10d. In the third embodiment, the step layer 5 of the first embodiment may be applied to one of the end surface exposed electrode layer 10c and the side surface exposed electrode layer 10d, and the step layer 5 of the second embodiment may be applied to the other. In the third embodiment, the step layer 5 that combines the first and second embodiments may be applied to at least one of the end surface exposed electrode layer 10c and the side surface exposed electrode layer 10d. In this way, the above-described embodiments can be combined in various ways.

[0106] (Method for Manufacturing Multilayer Ceramic Electronic Component) A method for manufacturing the multilayer ceramic electronic component 1 will now be described. (Preparation of Multilayer Block) Ceramic green sheets, electrode paste for the internal electrode layers 10, and step paste for the step layers 5 are prepared.

[0107] (Paste application) The electrode paste and step paste are applied to the ceramic green sheet in a desired pattern. The application of each paste to the ceramic green sheet can be performed by, for example, screen printing or gravure printing. The electrode paste and step paste are printed in a predetermined pattern on the ceramic green sheet using any printing method. This results in a ceramic green sheet for the inner layer portion 53 on which the paste is printed. The longitudinal distance between the step layer and the internal electrode layer can be controlled by changing the position where the step paste is applied.

[0108] (Lamination) A predetermined number of ceramic green sheets without the pattern of the internal electrode layer 10 printed thereon are laminated. This creates a portion corresponding to the outer layer portion 54. On top of this, ceramic green sheets for the inner layer portion 53 coated with paste are laminated in sequence. This creates a portion corresponding to the inner layer portion 53. Furthermore, on top of this, a predetermined number of ceramic green sheets for the other outer layer portion 54 are laminated. This creates a laminated sheet. The laminated sheet is pressed in the height direction using means such as an isostatic press to create a laminated block.

[0109] (Fabrication of laminated chips) The laminated block is cut to a predetermined size to cut out laminated chips, which may have rounded corners and ridges by barrel polishing or the like.

[0110] (Firing) Next, the laminated chip is fired to produce the laminate 2. The firing temperature depends on the materials of the ceramic layers 4 and the internal electrode layers 10, but is preferably 900°C or higher and 1400°C or lower.

[0111] (External Electrode) Next, the external electrode 20 is formed. (Base Layer) A conductive paste that will become the base layer 21 is applied to the two end faces 62 of the laminate 2 to form the base layer 21. To form the baked layer, a conductive paste containing a glass component and a metal is applied by a method such as dipping. Then, a baking process is performed to form the base layer 21. The baking temperature is preferably 500°C or higher and 900°C or lower. The baking time is preferably 30 minutes or higher and 2 hours or lower. The baking atmosphere is, for example, H ２ O and H ２ Preferably, the atmosphere is a reducing atmosphere containing

[0112] Next, a plating layer 23 is formed on the surface of the underlayer 21. In this embodiment, a Ni plating layer is formed on the baked layer. This Ni plating layer becomes the inner plating layer 23a. Next, a Sn plating layer is formed on the Ni plating layer. This Sn plating layer becomes the outer plating layer 23b. The Ni plating layer and the Sn plating layer are formed sequentially by, for example, barrel plating. In this manner, the multilayer ceramic electronic component 1 is obtained.

[0113] When a three-terminal multilayer ceramic capacitor is fabricated, external electrodes 20 are formed on the two side surfaces 63 as well as the two end surfaces 62 of the laminate 2 .

[0114] (Method of Measuring Thickness) As a method for measuring the length and thickness of the ceramic layers 4 and the internal electrode layers 10, for example, a method of observing a cross section of the laminate 2 exposed by polishing with a scanning electron microscope can be mentioned. Each value can be an average value of measurements taken at multiple locations corresponding to the part to be measured. The length of each part of the laminate 2 can be measured with a micrometer or an optical microscope. The step layer becomes thicker as it approaches the first main surface. At this time, the thickness between the first internal electrode layer and the first internal electrode layer closest to the first main surface becomes thicker as it approaches the first main surface.

[0115] (Coverage measurement method) Coverage can be measured, for example, as follows. The interior of the internal electrode layer 10 includes hollow portions where no metal is present. The coverage is defined as the proportion of the metal in the internal electrode layer 10. However, when the internal electrode layer 10 and the ceramic layer 4 are laminated, some of the hollows in the internal electrode layer 10 may be filled with ceramic material. Therefore, coverage is defined as metal / (metal + (hollows or ceramic material)). In other words, the entire internal electrode layer 10 is defined as the sum of (i) metal, (ii) parts that exist as hollows without being filled with ceramic material, and (iii) parts of the hollows that are filled with ceramic material. Then, the proportion of (i) metal to the entire internal electrode layer 10 is defined as coverage.

[0116] Specifically, coverage can be measured by the following method. First, the laminate 2 is polished to expose the cross section where coverage is to be measured. Then, the exposed surface is observed using an optical microscope or the like to determine the area of ​​the metal within a predetermined range. The coverage is calculated based on the determined area. Note that coverage can also be calculated by averaging values ​​determined at multiple locations.

[0117] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and various changes and modifications are possible.

[0118] REFERENCE SIGNS LIST 1 Multilayer ceramic electronic component 2 Laminate 4 Ceramic layer 5 Step layer 10 Internal electrode layer 11 Opposing portion 12 Extension portion 20 External electrode 21 Underlayer 23 Plating layer 30 Side surface external electrode 40 Bent portion 41 to 45 First bent portion to fifth bent portion 47 L-direction end portion 50 Electrode opposing portion 51 L gap 52 W gap 53 Inner layer portion 54 Outer layer portion 55 Extension region 61 Main surface 62 End surface 63 Side surface T Height direction L Length direction W Width direction

Claims

1. a first main surface and a second main surface that face each other in the height direction, a first side surface and a second side surface that face each other in the width direction orthogonal to the height direction, a first end surface and a second end surface that face each other in the length direction orthogonal to the height direction and the width direction, a first internal electrode layer exposed on the first end surface, a second internal electrode layer exposed on the second end surface, a laminate including a first step layer disposed on the same plane as the second internal electrode layer and exposed on the first end surface, a first external electrode provided on the first end surface, a second external electrode provided on the second end surface, the lengthwise distance between the first step layer and the second internal electrode layer is greater than the lengthwise distance between the first step layer and the second internal electrode layer located closer to the first main surface, a multilayer ceramic electronic component.

2. the lengthwise length of the first step layer is 20% or more of the lengthwise distance between the second internal electrode layer and the first end surface, the multilayer ceramic electronic component according to Claim 1.

3. the first internal electrode layer has an opposing portion where the first internal electrode layer and the second internal electrode layer oppose each other, and an extension portion extending from the opposing portion toward the first end surface, the extension portion has a bent portion that bends in the direction of the second main surface, the lengthwise length of the bent portion in the laminate is shorter than the lengthwise length of the bent portion located closer to the second main surface, the multilayer ceramic electronic component according to Claim 1 or 2.

4. The first internal electrode layer has an opposing portion where the first internal electrode layer and the second internal electrode layer oppose each other, and an extension portion extending from the opposing portion toward the first end surface, the extension portion has a bent portion that bends in the direction of the second main surface, when the height of the bent portion in the height direction of the laminate is defined by the distance in the height direction of the laminate between the point where bending starts and the point where bending ends, the height of the bent portion in the height direction of the laminate is lower than the height of the bent portion in the height direction of the laminate located closer to the second main surface, the multilayer ceramic electronic component according to Claim 1 or 2.

5. a first main surface and a second main surface that face each other in the height direction, a first side surface and a second side surface that face each other in the width direction orthogonal to the height direction, a first end surface and a second end surface that face each other in the length direction orthogonal to the height direction and the width direction, An end-face exposed electrode layer which is an internal electrode layer exposed on the first end face and the second end face, A side-face exposed electrode layer which is an internal electrode layer exposed on the first side face and the second side face, A laminate including a side-step layer disposed on the same plane as the side-face exposed electrode layer and exposed on the first side face and the second side face, A first external electrode provided on the first end face and the second end face, A second external electrode provided on the first side face and the second side face, and comprising, The distance in the width direction between the side-step layer and the side-face exposed electrode layer is greater than the distance in the width direction between the side-step layer and the side-face exposed electrode layer located closer to the first main face, A multilayer ceramic electronic component.

6. A first main face and a second main face opposite in the height direction, A first side face and a second side face opposite in the width direction orthogonal to the height direction, A first end face and a second end face opposite in the length direction orthogonal to the height direction and the width direction, An end-face exposed electrode layer which is an internal electrode layer exposed on the first end face and the second end face, A side-face exposed electrode layer which is an internal electrode layer exposed on the first side face and the second side face, A laminate including a side-step layer disposed on the same plane as the side-face exposed electrode layer and exposed on the first side face and the second side face, A first external electrode provided on the first end face and the second end face, A second external electrode provided on the first side face and the second side face, and comprising, The distance in the length direction between the side-step layer and the side-face exposed electrode layer is greater than the distance in the length direction between the side-step layer and the side-face exposed electrode layer located closer to the first main face, A multilayer ceramic electronic component.

7. A first main face and a second main face opposite in the height direction, A first side face and a second side face opposite in the width direction orthogonal to the height direction, A first end face and a second end face opposite in the length direction orthogonal to the height direction and the width direction, An end-face exposed electrode layer which is an internal electrode layer exposed on the first end face and the second end face, A side-face exposed electrode layer which is an internal electrode layer exposed on the first side face and the second side face, A laminate including an end-step layer disposed on the same plane as the side-face exposed electrode layer and exposed on the first end face and the second end face, A first external electrode provided on the first end face and the second end face, A second external electrode provided on the first side face and the second side face, and comprising, The lengthwise distance between the end face step layer and the side face exposed electrode layer is such that the lengthwise distance between the end face step layer and the side face exposed electrode layer located closer to the first main surface is greater. Multilayer ceramic electronic component. **Claim 8** A first main surface and a second main surface that face each other in the height direction, A first side surface and a second side surface that face each other in the width direction orthogonal to the height direction, A first end face and a second end face that face each other in the length direction orthogonal to the height direction and the width direction, An end face exposed electrode layer that is an internal electrode layer exposed on the first end face and the second end face, A side face exposed electrode layer that is an internal electrode layer exposed on the first side face and the second side face, A laminate including a side face step layer that is disposed on the same plane as the end face exposed electrode layer and is exposed on the first side face and the second side face, A first external electrode provided on the first end face and the second end face, A second external electrode provided on the first side face and the second side face, and comprising: The widthwise distance between the side face step layer and the end face exposed electrode layer is such that the widthwise distance between the side face step layer and the end face exposed electrode layer located closer to the first main surface is greater. Multilayer ceramic electronic component. **Claim 9** A first main surface and a second main surface that face each other in the height direction, A first side surface and a second side surface that face each other in the width direction orthogonal to the height direction, A first end face and a second end face that face each other in the length direction orthogonal to the height direction and the width direction, An end face exposed electrode layer that is an internal electrode layer exposed on the first end face and the second end face, A side face exposed electrode layer that is an internal electrode layer exposed on the first side face and the second side face, A laminate including an end face step layer that is disposed on the same plane as the end face exposed electrode layer and is exposed on the first end face and the second end face, A first external electrode provided on the first end face and the second end face, A second external electrode provided on the first side face and the second side face, and comprising: The widthwise distance between the end face step layer and the end face exposed electrode layer is such that the widthwise distance between the end face step layer and the end face exposed electrode layer located closer to the first main surface is greater. Multilayer ceramic electronic component. **Claim 10** A first main surface and a second main surface that face each other in the height direction, A first side surface and a second side surface that face each other in the width direction orthogonal to the height direction, A first end face and a second end face that face each other in the length direction orthogonal to the height direction and the width direction, An end-face exposed electrode layer which is an internal electrode layer exposed on the first end face and the second end face; A side-face exposed electrode layer which is an internal electrode layer exposed on the first side face and the second side face; A laminate including an end-face step layer which is disposed on the same plane as the end-face exposed electrode layer and is exposed on the first end face and the second end face; A first external electrode provided on the first end face and the second end face; A second external electrode provided on the first side face and the second side face, and comprising: The distance in the length direction between the end-face step layer and the end-face exposed electrode layer is such that the distance in the length direction between the end-face step layer and the end-face exposed electrode layer located at a position closer to the first main face is greater; A multilayer ceramic electronic component.