Laminated coil component and method for manufacturing laminated coil component

Abstract

This laminated coil component 1 comprises: a laminate 10 formed by laminating a plurality of insulating layers 31 in a lamination direction and having an internal electrode; and a first external electrode 21 and a second external electrode 22 which are provided on an outer surface of the laminate 10. The internal electrode includes: a first lead-out conductor 41 extending in the lamination direction and connected to the first external electrode 21; and a second lead-out conductor 42 extending in the lamination direction and connected to the second external electrode 22. The first lead-out conductor 41 has: a via conductor 33e penetrating the insulating layers 10; and a land 35e provided on the insulating layers 10. When the end in direct contact with the first external electrode 21 among the two ends of the first lead-out conductor 41 in the lamination direction is referred to as a first end 41a, the first external electrode 21 is in direct contact with not only the first end 41a but also at least one first land 51 spaced apart from the first end 41a among the lands 35e of the first lead-out conductor 41.

Description

Multilayer coil component and manufacturing method thereof

[0001] The present invention relates to a laminated coil component and a method for manufacturing a laminated coil component.

[0002] Patent Document 1 describes a multilayer electronic component in which a coil is formed inside by stacking coil conductors and insulating layers made of magnetic or non-magnetic materials, and which has terminal electrodes on both ends in the stacking direction, with the terminal electrode on at least one end connected to the end of the coil inside the laminate via a conductor-filled through hole provided in one or more insulating layers and an extraction electrode provided so as to cover the end of the through hole, and in which the area of ​​the extraction electrode is set to be three times or more the cross-sectional area of ​​the through hole and one-third or less of the internal area of ​​the coil when the laminate is viewed perspectively in the stacking direction.

[0003] Japanese Patent Application Laid-Open No. 2002-15918

[0004] In the multilayer electronic component described in Patent Document 1, the coil conductor and the terminal electrode (external electrode) are connected via a lead conductor composed of a conductor-filled through hole and a lead electrode. However, when only the end face of the lead conductor is connected to the external electrode, as in the multilayer electronic component described in Patent Document 1, current concentrates at the end face, increasing the current density. As a result, heat generated by the current concentration can break the current-concentrated area, potentially causing a break. Furthermore, even if a break does not occur, the resistance of the lead conductor can increase.

[0005] The present invention has been made to solve the above problems, and has an object to provide a laminated coil component that can suppress current concentration at end faces of lead conductors. Another object of the present invention is to provide a method for manufacturing the laminated coil component.

[0006] The laminated coil component of the present invention comprises a laminate formed by stacking a plurality of insulating layers in a stacking direction and having an internal electrode, and first external electrodes and second external electrodes provided on outer surfaces of the laminate, wherein the internal electrodes have a first lead conductor extending in the stacking direction and connected to the first external electrode, and a second lead conductor extending in the stacking direction and connected to the second external electrode, the first lead conductor having via conductors penetrating the insulating layers and lands provided on the insulating layers, and wherein, of both ends of the first lead conductor in the stacking direction, the one that is in direct contact with the first external electrode is defined as a first end, and the first external electrode is in direct contact with at least one first land of the lands of the first lead conductor that is spaced from the first end, in addition to the first end.

[0007] a step of performing a barrel polishing process on the laminate; and a step of forming an external electrode on an outer surface of the barrel-polished laminate, wherein the internal electrodes have a first lead conductor and a second lead conductor each extending in the stacking direction, and the first lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer; in the step of preparing the laminate, one first end of both ends of the first lead conductor in the stacking direction is exposed from the laminate, and none of the lands of the first lead conductor spaced from the first end is exposed from the laminate; in the step of performing the barrel polishing process, the laminate is polished to expose at least one first land spaced from the first end from the laminate; and in the step of forming the external electrode, a first external electrode is formed so as to cover the first end and at least one first land exposed from the laminate.

[0008] A second aspect of the method for producing a laminated coil component of the present invention includes the steps of: preparing a laminate block having internal electrodes formed by stacking a plurality of insulating layers in a stacking direction; dividing the laminate block into individual laminates; and forming external electrodes on the laminates, wherein the internal electrodes have first and second lead conductors extending in the stacking direction, and the first lead conductors have via conductors penetrating the insulating layers and lands provided on the insulating layers. In the step of preparing the laminate block, Of the two ends of the body in the stacking direction, one first end is exposed from the laminate block, and none of the lands of the first extraction conductor that are spaced apart from the first end are exposed from the laminate, and in the process of dividing the laminate block, the laminate block is cut to expose at least one first land that is spaced apart from the first end from the laminate, and in the process of forming the external electrode, a first external electrode is formed to cover the first end and at least one of the first lands exposed from the laminate.

[0009] According to the present invention, it is possible to provide a laminated coil component that can suppress current concentration at the end faces of the lead conductors. Also, according to the present invention, it is possible to provide a method for manufacturing the laminated coil component.

[0010] FIG. 1 is a perspective view schematically illustrating an example of a laminated coil component of the present invention. FIG. 2 is an exploded perspective view schematically illustrating an example of a laminate constituting the laminated coil component shown in FIG. 1. FIG. 3 is a side view schematically illustrating, in a see-through manner, an example of the internal structure of a laminate constituting the laminated coil component shown in FIG. 1. FIG. 4 is a cross-sectional view schematically illustrating an example of a cross section taken along line A1-A1 of the laminated coil component shown in FIG. 1. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 3. FIG. 6 is a side view schematically illustrating, in a see-through manner, an example of the internal structure of a laminate constituting a first modified example of the laminated coil component of the present invention. FIG. 7 is a side view schematically illustrating, in a see-through manner, an example of the internal structure of a laminate constituting a second modified example of the laminated coil component of the present invention. FIG. 8 is a side view schematically illustrating, in a see-through manner, an example of the internal structure of a laminate constituting a third modified example of the laminated coil component of the present invention. FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 8. FIG. 10 is a perspective view schematically illustrating a fourth modified example of the laminated coil component of the present invention. FIG. 11 is a perspective side view schematically showing an example of the internal structure of a laminate constituting a fourth modified example of the laminated coil component of the present invention. FIG. 12 is a perspective view schematically showing a fifth modified example of the laminated coil component of the present invention. FIG. 13 is a perspective side view schematically showing an example of the internal structure of a laminate constituting a fifth modified example of the laminated coil component of the present invention. FIG. 14 is an exploded perspective view schematically showing an example of a laminate produced in the step of preparing a laminate in the first embodiment of the method for producing a coil component of the present invention. FIG. 15 is a perspective side view schematically showing an example of the internal structure of a laminate produced in the step of preparing a laminate in the first embodiment of the method for producing a coil component of the present invention. FIG. 16 is a perspective side view schematically showing an example of the internal structure of a laminate after the step of performing a barrel polishing treatment in the first embodiment of the method for producing a coil component of the present invention. FIG. 17 is a perspective side view schematically showing an example of the internal structure of a laminate after the step of forming external electrodes in the first embodiment of the method for producing a coil component of the present invention. FIG. 18 is a perspective view schematically showing an example of a laminate block produced in the step of preparing a laminate block in the second embodiment of the method for producing a laminated coil component of the present invention, as seen from the stacking direction.

[0011] The laminated coil component of the present invention will be described below. Note that the present invention is not limited to the following configurations and may be modified as appropriate without departing from the gist of the present invention. Furthermore, a combination of multiple individual preferred configurations described below also constitutes the present invention.

[0012] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, and other scales may differ from those of the actual product. In the drawings, the same or equivalent parts will be designated by the same reference numerals. In addition, the same elements will be designated by the same reference numerals in each drawing, and duplicate explanations will be omitted.

[0013] In this specification, terms indicating the relationship between elements (e.g., "parallel," "orthogonal," etc.) and terms indicating the shape of elements not only mean the literal strict form, but also mean a range that is substantially equivalent, for example, a range that includes a difference of about a few percent.

[0014] The following embodiments are merely examples, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. From the second embodiment onwards, a description of the matters common to the first embodiment will be omitted, and only the differences will be described. In particular, similar effects due to similar configurations will not be mentioned in each embodiment.

[0015] FIG. 1 is a perspective view schematically illustrating an example of a laminated coil component of the present invention. The laminated coil component 1 shown in FIG. 1 includes a laminate (element body) 10 and a first external electrode 21 and a second external electrode 22 provided on the outer surface of the laminate 10. The laminate 10 has a roughly rectangular parallelepiped shape with six sides. The configuration of the laminate 10 will be described later. The laminate 10 includes multiple insulating layers stacked in the stacking direction and has internal electrodes. The internal electrodes include coil conductors. The laminate 10 includes multiple insulating layers and multiple coil conductors stacked in the stacking direction, and a coil is provided therein. The internal electrodes include a first lead conductor connected to the first external electrode 21 and a second lead conductor connected to the second external electrode 22. The first external electrode and the second external electrode are electrically connected to the coil by the first lead conductor and the second lead conductor, respectively.

[0016] In the laminated coil component and laminate in this specification, the length direction, height direction, and width direction are defined as the L direction, T direction, and W direction in Fig. 1. Here, the length direction L, height direction T, and width direction W are perpendicular to each other. Here, the length direction L is a direction parallel to the stacking direction.

[0017] As shown in FIG. 1 , the laminate 10 has a first end face 11 and a second end face 12 facing in a longitudinal direction L, a first main surface 13 and a second main surface 14 facing in a height direction T perpendicular to the longitudinal direction L, and a first side surface 15 and a second side surface 16 facing in a width direction W perpendicular to the longitudinal direction L and the height direction T.

[0018] The corners and ridges of the laminate 10 are preferably rounded. A corner is a portion where three surfaces of the laminate intersect, and a ridge is a portion where two surfaces of the laminate intersect. In this specification, the term "approximately rectangular parallelepiped shape" includes a shape in which at least one corner or ridge of the rectangular parallelepiped is rounded.

[0019] As shown in FIG. 1 , the first external electrode 21 covers the entire first end surface 11 of the laminate 10 and extends from the first end surface 11 to cover a portion of the first main surface 13, a portion of the second main surface 14, a portion of the first side surface 15, and a portion of the second side surface 16.

[0020] As shown in FIG. 1 , the second external electrode 22 covers the entire second end surface 12 of the laminate 10 and extends from the second end surface 12 to cover a portion of the first main surface 13, a portion of the second main surface 14, a portion of the first side surface 15, and a portion of the second side surface 16.

[0021] When the laminated coil component 1 having the first external electrodes 21 and the second external electrodes 22 arranged as described above is mounted on a substrate, any one of the first main surface 13, the second main surface 14, the first side surface 15, and the second side surface 16 of the laminate 10 becomes the mounting surface.

[0022] However, it is sufficient that the first external electrode 21 extends from at least a portion of the first end surface 11 of the laminate 10 to the mounting surface of the laminate 10 .

[0023] Similarly, the second external electrode 22 may extend from at least a portion of the second end surface 12 of the laminate 10 to the mounting surface of the laminate 10 .

[0024] The first external electrode 21 and the second external electrode 22 may each have a single-layer structure or a multi-layer structure.

[0025] When the first external electrode 21 and the second external electrode 22 each have a single-layer structure, examples of the constituent materials of each external electrode include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0026] When the first external electrode 21 and the second external electrode 22 each have a multi-layer structure, each external electrode may have, in order from the surface side of the laminate 10, for example, a base electrode layer containing Ag, a Ni-plated electrode, and a Sn-plated electrode.

[0027] The size of the laminated coil component of the present invention is not particularly limited, but may be 0603 size, 0402 size, 1005 size, or 1608 size.

[0028] FIG. 2 is an exploded perspective view schematically showing an example of a laminate constituting the laminated coil component shown in FIG. 1 .

[0029] 2 , the laminate 10 is configured by stacking a plurality of insulating layers 31a, 31b, 31c, 31d, 31e, and 31f in a stacking direction (here, length direction L) from the first end face 11 side toward the second end face 12 side of the laminate 10. Hereinafter, the insulating layers 31a, 31b, 31c, 31d, 31e, and 31f will also be collectively referred to as insulating layers 31.

[0030] In this specification, the direction in which the insulating layers constituting the laminate are stacked is referred to as the stacking direction.

[0031] In FIG. 2, the insulating layer 31e is disposed on the lower side in the stacking direction (the first end face 11 side of the laminate 10), and the insulating layer 31f is disposed on the upper side in the stacking direction (the second end face 12 side of the laminate 10).

[0032] The insulating layers 31 may be made of a magnetic material such as a ferrite material.

[0033] The insulating layers 31a, 31b, 31c, and 31d are provided with coil conductors 32a, 32b, 32c, and 32d, and via conductors 33a, 33b, 33c, and 33d, respectively. The insulating layer 31e is provided with a via conductor 33e and a land 35e. The insulating layer 31f is provided with a via conductor 33f and a land 35f. The insulating layer 31e may be a single layer or two or more layers. Similarly, the insulating layer 31f may be a single layer or two or more layers. Hereinafter, the coil conductors 32a, 32b, 32c, and 32d will also be collectively referred to as coil conductors 32.

[0034] The coil conductors 32a, 32b, 32c, and 32d are provided on the main surfaces of the insulating layers 31a, 31b, 31c, and 31d, respectively, and are stacked together with the insulating layers 31a, 31b, 31c, 31d, 31e, and 31f. In Fig. 2, each coil conductor 32 has a 3 / 4 turn shape, and four insulating layers 31 arranged in the order of 31a, 31b, 31c, and 31d constitute one unit (three turns), which are repeatedly stacked.

[0035] The coil conductors 32a, 32b, 32c, and 32d each include an annular winding portion 34a, 34b, 34c, and 34d that is partially missing, leaving a gap, and lands 35a, 35b, 35c, and 35d. Lands 35a, 35b, 35c, and 35d are provided at both ends of each winding portion 34a, 34b, 34c, and 34d, respectively. Hereinafter, the winding portions 34a, 34b, 34c, and 34d will also be collectively referred to as winding portion 34.

[0036] The via conductors 33a, 33b, 33c, 33d, 33e, and 33f are provided to penetrate the insulating layers 31a, 31b, 31c, 31d, 31e, and 31f, respectively, in the stacking direction. Hereinafter, the via conductors 33a, 33b, 33c, 33d, 33e, and 33f will also be collectively referred to as via conductors 33.

[0037] Lands 35e and 35f are provided directly above via conductors 33e and 33f, respectively. The lands 35a, 35b, 35c, 35d, 35e, and 35f are preferably slightly larger than the line width of winding portions 34a, 34b, 34c, and 34d. Hereinafter, lands 35a, 35b, 35c, 35d, 35e, and 35f will also be collectively referred to as land 35. Land 35 is larger than adjacent via conductors 33, and when viewed in the stacking direction (lengthwise direction L), the via conductors 33 adjacent to land 35 are contained within the area of ​​that land 35.

[0038] Examples of materials that can be used to form each coil conductor 32 including the winding portion 34 and the land 35, and each via conductor 33 include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0039] The insulating layers 31a, 31b, 31c, 31d, 31e, and 31f configured as described above are stacked in the stacking direction to form the laminate 10, and the coil conductors 32a, 32b, 32c, and 32d are electrically connected via the via conductors 33a, 33b, 33c, and 33d. As a result, a solenoid coil having a coil axis parallel to the stacking direction is formed within the laminate 10.

[0040] The via conductor 33e and the land 35e form a first extension conductor. The first extension conductor is exposed at the first end surface 11 of the laminate 10. That is, the first extension conductor includes the via conductor 33e and the land 35e. As shown in FIG. 2 , the via conductor 33e is present in the portion of the first extension conductor that is exposed at the first end surface 11 of the laminate 10. As will be described later, the first extension conductor connects the first external electrode 21 and the coil conductor 32a facing it within the laminate 10.

[0041] The via conductors 33f and the lands 35f form a second extension conductor. The second extension conductor is exposed at the second end surface 12 of the laminate 10. That is, the second extension conductor includes the via conductors 33f and the lands 35f. As shown in FIG. 2 , the land 35f is present in the portion of the second extension conductor that is exposed at the second end surface 12 of the laminate 10. As will be described later, the second extension conductor connects the second external electrode 22 and the coil conductor 32d facing it within the laminate 10.

[0042] When viewed from the stacking direction (length direction L), the coil conductors 32 preferably overlap each other. Furthermore, when viewed from the stacking direction, the coil may have a shape composed of straight portions (e.g., a polygonal shape such as a rectangle) as shown in Fig. 2, a shape composed of curved portions (e.g., a circular shape), or a shape composed of straight portions and curved portions.

[0043] FIG. 3 is a perspective side view schematically showing an example of the internal structure of a laminate constituting the laminated coil component shown in FIG. 1 .

[0044] 3 , in the laminated coil component 1, a plurality of insulating layers 31 are stacked in the length direction L, and therefore the length direction L is the stacking direction. The stacking direction of the laminate 10 and the coil axis A of the coil 30 are parallel to the first main surface 13, the second main surface 14, the first side surface 15, or the second side surface 16, which are mounting surfaces.

[0045] As shown in FIG. 3, in reality, no boundary between adjacent insulating layers 31 is visible.

[0046] 2 and 3 illustrate an example in which the number of laminations of the coil conductor 32 for forming three turns of the coil 30 is four, i.e., the repeating shape is a ¾ turn shape, but there is no particular limitation on the number of laminations of the coil conductor 32 for forming one turn of the coil 30. For example, the number of laminations of the coil conductor 32 for forming one turn of the coil 30 may be two, i.e., the repeating shape may be a ½ turn shape.

[0047] Furthermore, the number of layers of the coil conductors 32, i.e., the total number of layers of the coil conductors 32 included in the laminate 10, is not particularly limited.

[0048] FIG. 4 is a cross-sectional view schematically showing an example of a cross section of the laminated coil component shown in FIG. 1 taken along line A1-A1.

[0049] As shown in Fig. 4, when viewed in a cross section perpendicular to the direction in which the coil conductor 32 extends, the cross-sectional shape of the coil conductor 32 is flat, and its longitudinal direction is perpendicular to the stacking direction (length direction L). In the example shown in Fig. 4, the cross-sectional shape of the coil conductor 32 is an ellipse whose major axis is perpendicular to the stacking direction, but the cross-sectional shape of the coil conductor 32 is not particularly limited and may be, for example, a rectangle with a pair of sides opposite each other in the stacking direction having the same length, or a trapezoid with a pair of sides opposite each other in the stacking direction having different lengths.

[0050] The first lead conductor 41 will be described below with reference to FIGS.

[0051] The first extension conductor 41 extends in the stacking direction within the laminate 10 and linearly connects the first external electrode 21 provided on the first end face 11 to the opposing coil conductor 32a. The first extension conductor 41 has a via conductor 33e penetrating the insulating layer 31e and a land 35e provided on the insulating layer 31e.

[0052] When viewed from the stacking direction (lengthwise direction L), it is preferable that the via conductors 33e that constitute the first extraction conductor 41 overlap each other, but the via conductors 33e that constitute the first extraction conductor 41 do not have to be arranged in a strictly straight line.

[0053] Of the two ends in the stacking direction, the first extension conductor 41 has a first end 41a that is in direct contact with the first external electrode 21. A via conductor 33e of the first extension conductor 41 is present at the first end 41a.

[0054] The first external electrode 21 is in direct contact with at least one first land 51, which is spaced from the first end 41 a, among the lands 35 e of the first extension conductor 41, in addition to the first end 41 a. In the laminated coil component 1, of the lands 35 e of the first extension conductor 41, the land 35 e that is closest to the first end face 11 is exposed from the laminate 10 and serves as the first land 51. The first external electrode 21 covers the portion of the first land 51 that is exposed from the laminate 10, thereby bringing the first land 51 and the first external electrode 21 into direct contact. In the laminated coil component 1, the first extension conductor 41 has one first land 51. At least one via conductor 33 e is present between the first land 51 and the first end 41 a.

[0055] In the laminated coil component of the present invention, the first external electrode 21 is in direct contact with not only the first end 41 a but also at least one first land 51 spaced apart from the first end 41 a. Therefore, compared to when the first extension conductor 41 is connected to the first external electrode 21 only at the first end 41 a, the contact area between the first external electrode 21 and the first extension conductor 41 is larger by the amount of direct contact between the first land 51 and the first external electrode 21. In the laminated coil component of the present invention, the current is also dispersed to the first land 51, making it possible to suppress current concentration at the first end 41 a.

[0056] By suppressing current concentration at the first end 41 a of the first extension conductor 41, it is possible to suppress breakage of the current concentration portion due to heat generation caused by current concentration. It is also possible to suppress an increase in resistance of the first extension conductor 41 even if it does not lead to breakage.

[0057] FIG. 5 is a cross-sectional view taken along line VV in FIG.

[0058] FIG. 5 shows a cross section including the first land 51 .

[0059] 5 , the outer periphery of the first land 51 is in direct contact with the first external electrode 21. More specifically, only a portion of the outer periphery of the first land 51 is in direct contact with the first external electrode 21, and the remaining portion of the outer periphery and the inner portion of the first land 51 (the central portion surrounded by the outer periphery) are not exposed from the laminate 10 and are not in contact with the first external electrode 21.

[0060] The first land 51 is in direct contact with the first external electrode 21 at the ridge portion of the laminate 10. As shown in Fig. 5 , the first land 51 is in direct contact with the first external electrode 21 at the ridge portion formed by the second main surface 14 and the first side surface 15 of the laminate 10.

[0061] When the first land 51 is in direct contact with the first external electrode 21 at the ridge portion of the laminate 10, the laminate 10 may be a substantially hexahedron, and the first land 51 may be in direct contact with the first external electrode 21 at the ridge portion of the substantially hexahedron laminate 10. The substantially hexahedron may be, for example, a substantially rectangular parallelepiped. The substantially rectangular parallelepiped includes a rectangular parallelepiped having at least one rounded corner or ridge portion.

[0062] The ridges of the laminate 10 may be rounded, and the first lands 51 may be in direct contact with the first external electrodes 21 at the rounded ridges of the laminate 10. For example, by adjusting the rounding of the ridges of the laminate 10, the first lands 51 can be exposed from the laminate 10 and come into direct contact with the first external electrodes 21.

[0063] When the first land 51 is in direct contact with the first external electrode 21 at the ridge portion of the laminate 10, the contact area between the first land 51 and the first external electrode 21 can be increased. This makes it possible to further suppress current concentration at the first end 41 a. Furthermore, a structure in which the first land 51 is in direct contact with the first external electrode 21 at the ridge portion of the laminate 10 is easy to manufacture, and the contact area between the first land 51 and the first external electrode 21 can be easily controlled.

[0064] The first land 51 may be exposed from the laminate 10 at the first main surface 13, the second main surface 14, the first side surface 15 or the second side surface 16, rather than at the ridge portion of the laminate 10, and may be in direct contact with the first external electrode 21.

[0065] The shape of the first land 51 is not particularly limited. For example, when viewed in the stacking direction (lengthwise direction L), the first land 51 may have a circular shape, or may have an oval, elliptical, or polygonal shape such as a rectangle. Furthermore, the above shape may be missing or interrupted at the location where it contacts the first external electrode 21. When viewed in the stacking direction (lengthwise direction L), the shape of the first land 51 and the lands 35e of the first extension conductor 41 that do not contact the first external electrode 21 may be the same or different.

[0066] Next, the second lead conductor 42 will be described with reference to FIGS.

[0067] The second extension conductor 42 extends in the stacking direction within the laminate 10 and linearly connects the second external electrode 22 provided on the second end face 12 to the coil conductor 32d facing it. The second extension conductor 42 has a via conductor 33f penetrating the insulating layer 31f and a land 35f provided on the insulating layer 31f.

[0068] When viewed from the stacking direction (lengthwise direction L), it is preferable that the via conductors 33f that constitute the second extraction conductor 42 overlap each other, but the via conductors 33f that constitute the second extraction conductor 42 do not have to be arranged in a strictly straight line.

[0069] The second extension conductor 42 has two ends in the stacking direction, and the second end 42a is in direct contact with the second external electrode 22. A land 35f of the second extension conductor 42 is present at the second end 42a. The land 35f provided at the second end 42a may have a partially missing shape due to the rounding of the corners of the laminate 10.

[0070] The second external electrode 22 is in direct contact with at least one second land 52, which is spaced from the second end 42a, among the lands 35f of the second extension conductor 42, in addition to the second end 42a. In the laminated coil component 1, of the lands 35f spaced from the second end 42a, the land 35f closest to the second end face 12 (the second land 35f from the right in FIG. 3 ) serves as the second land 52. In the laminated coil component 1, the second extension conductor 42 has one second land 52. At least one via conductor 33f is present between the second land 52 and the second end 42a. The second land 52 may have the same configuration as the first land 51, except that the second land 52 is in direct contact with a different external electrode.

[0071] If the second extension conductor 42 has the second land 52, the current is dispersed to the second land 52, thereby suppressing current concentration at the second end 42 a. By suppressing current concentration at the second end 42 a, it is possible to suppress breakage of the current-concentrated portion due to heat generation caused by current concentration. It is also possible to suppress an increase in the resistance of the second extension conductor 42, even if it does not lead to breakage.

[0072] 2 and 3 show a configuration in which the via conductor 33e is present at the first end 41a and the land 35f is present at the second end 42a, but a land may be present at the first end 41a and a via conductor may be present at the second end 42a. Furthermore, the first lead-out conductor 41 may have the configuration described herein as the configuration of the second lead-out conductor 42, and the second lead-out conductor 42 may have the configuration described herein as the configuration of the first lead-out conductor 41.

[0073] The positional relationship between the first extension conductor 41 and the second extension conductor 42 is not particularly limited, but the first extension conductor 41 and the second extension conductor 42 may or may not overlap when viewed from the stacking direction. The entire first extension conductor 41 and the entire second extension conductor 42 may overlap, or a part of the first extension conductor 41 and a part of the second extension conductor 42 may overlap.

[0074] Next, a first modified example of the laminated coil component of the present invention will be described.

[0075] FIG. 6 is a side view showing a schematic perspective view of an example of the internal structure of a laminate constituting a first modified example of the laminated coil component of the present invention.

[0076] In the laminated coil component 1A shown in FIG. 6, the first external electrode 21 is in direct contact with two or more first lands 51 in addition to the first end 41a.

[0077] When the first external electrode 21 is in direct contact with two or more first lands 51, the current is dispersed to two or more first lands 51, thereby further suppressing current concentration at the first end 41a.

[0078] In the laminated coil component 1A, the first extension conductor 41 has three first lands 51. The number of first lands 51 included in the first extension conductor 41 is not particularly limited, and may be two, or may be three or more.

[0079] In the laminated coil component 1A, the three lands 35e present on the first end face 11 side serve as first lands 51. Between the first end 41a and each of the first lands 51, there is no land that does not come into contact with the first external electrode 21.

[0080] When the first external electrode 21 is in direct contact with two or more first lands 51, the sizes of the two or more first lands 51 may be the same or different when viewed from the stacking direction.

[0081] In the laminated coil component 1A, the second external electrode 22 is in direct contact with two or more second lands 52 in addition to the second end 42a.

[0082] When the second external electrode 22 is in direct contact with two or more second lands 52, the current is dispersed to two or more second lands 52, thereby further suppressing current concentration at the second end 42a.

[0083] In the laminated coil component 1A, the second lead conductor 42 has two second lands 52. The number of second lands 52 included in the second lead conductor 42 is not particularly limited, and may be two, or may be three or more.

[0084] In the laminated coil component 1A, the two lands 35f present on the second end face 12 side serve as the second lands 52. Between the second end 42a and each second land 52, there is no land that does not come into contact with the second external electrode 22.

[0085] Next, a second modified example of the laminated coil component of the present invention will be described.

[0086] FIG. 7 is a side view showing a schematic perspective view of an example of the internal structure of a laminate constituting a second modified example of the laminated coil component of the present invention.

[0087] 7 , in the first lead conductor 41, a land 35e2 that is not exposed from the laminate 10 and does not contact the first external electrode 21 is present between the first end 41a and the first land 51. In the laminate coil component 1B, the second land 35e from the first end face 11 side (second from the left in FIG. 7 ) is present between the first end 41a and the first land 51 and is the land 35e2 that does not contact the first external electrode 21.

[0088] That is, in the laminated coil component 1B, the first extension conductor 41 has two or more lands 35e, and the two or more lands 35e of the first extension conductor 41 include a land 35e2 between the first end 41a and the first land 51 that does not contact the first external electrode 21.

[0089] If the land 35e2 that does not contact the first external electrode 21 exists between the first end 41a and the first land 51, the distance between the first end 41a and the first land 51 increases. Therefore, when heat is generated at the first end 41a and the first land 51 due to the concentration of power, the distance between the heat generating points increases, which further prevents the conductor from overheating and breaking.

[0090] When the first lead conductor 41 has two or more first lands 51, there may be a land 35e2 between adjacent first lands 51 that is not exposed from the laminate 10 and does not contact the first external electrode 21.

[0091] In the laminated coil component 1B, the second lead conductor 42 has a land 35f2 between the second end 42a and the second land 52, which is not exposed from the laminate 10 and does not contact the second external electrode 22. In the laminated coil component 1B, the second land 35f from the second end face 12 side (the second from the right in FIG. 7 ) is the land 35f2 that is between the second end 42a and the second land 52 and does not contact the second external electrode 22.

[0092] That is, in the laminated coil component 1B, the second extraction conductor 42 has two or more lands 35f, and the two or more lands 35f of the second extraction conductor 42 include a land 35f2 between the second end 42a and the second land 52 that does not contact the second external electrode 22.

[0093] If a land 35f2 that does not contact the second external electrode 22 exists between the second end 42a and the second land 52, the distance between the second end 42a and the second land 52 increases. Therefore, when heat is generated at the second end 42a and the second land 52 due to the concentration of power, the distance between the heat generating points increases, which further prevents the conductor from overheating and breaking.

[0094] When the second lead conductor 42 has two or more second lands 52, there may be a land 35f2 between adjacent second lands 52 that is not exposed from the laminate 10 and does not contact the second external electrode 22.

[0095] Next, a third modified example of the laminated coil component of the present invention will be described.

[0096] FIG. 8 is a perspective side view schematically showing an example of the internal structure of a laminate constituting a third modified example of the laminated coil component of the present invention.

[0097] In the laminated coil component 1C shown in FIG. 8 , the internal electrode has, in addition to the first extension conductor 41 , a third extension conductor 43 connected to the first external electrode 21 .

[0098] The third lead conductor 43 has a via conductor 33 that penetrates the insulating layer 31 and a land 35 provided on the insulating layer 31 .

[0099] The third extension conductor 43 extends in the stacking direction. Of the two ends in the stacking direction, the third extension conductor 43 has a third end 43 a that is in direct contact with the first external electrode 21. A via conductor 33 is provided at the third end 43 a, but a land 35 may also be provided at the third end 43 a.

[0100] The first external electrode 21 is in direct contact with not only the third end 43 a but also at least one third land 53 spaced apart from the third end 43 a among the lands 35 of the third lead conductor 43. In the laminated coil component 1C, one third land 53 is in direct contact with the first external electrode 21, but two or more third lands 53 may be in direct contact with the first external electrode 21.

[0101] The presence of the third extension conductor 43 further reduces current concentration at the first end 41 a because the current flowing through the first extension conductor 41 is also dispersed to the third extension conductor 43. Furthermore, in the third extension conductor 43, the current is dispersed to the third land 53, which also reduces current concentration at the third end 43 a.

[0102] The third extension conductor 43 may have the same configuration as the first extension conductor 41 except that the positions at which it contacts the coil conductor 32 and the first external electrode 21 are different.

[0103] In the laminated coil component 1C, the internal electrode may have, in addition to the second lead conductor 42 , a fourth lead conductor 44 connected to the second external electrode 22 .

[0104] The fourth extension conductor 44 may have the same configuration as the second extension conductor 42, except for the contact positions with the coil conductor 32 and the second external electrode 22. The fourth extension conductor 44 has two ends in the stacking direction, and a fourth end 44a of the fourth extension conductor 44 is in direct contact with the second external electrode 22. The fourth extension conductor 44 has at least one fourth land 54 that is spaced from the fourth end 44a and in contact with the second external electrode 22.

[0105] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG.

[0106] In the laminated coil component 1C, the internal electrodes include a fifth lead conductor 45 and a seventh lead conductor 47 connected to the first external electrode 21, in addition to the first lead conductor 41 and the third lead conductor 43. The fifth lead conductor 45 is in direct contact with the first external electrode 21 at a fifth end thereof in the stacking direction. The fifth lead conductor 45 has at least one fifth land 55 spaced from the fifth end and in direct contact with the first external electrode 21. The seventh lead conductor 47 is in direct contact with the first external electrode 21 at a seventh end thereof in the stacking direction. The seventh lead conductor 47 has at least one seventh land 57 spaced from the seventh end and in contact with the first external electrode 21.

[0107] The fifth lead conductor 45 and the seventh lead conductor 47 may have the same configuration as the first lead conductor 41 and the third lead conductor 43, except that the contact positions with the coil conductor 32 and the first external electrode 21 are different.

[0108] The first extension conductor 41, the third extension conductor 43, the fifth extension conductor 45, and the seventh extension conductor 47 are connected in parallel between the coil and the first external electrode 21. For example, the first extension conductor 41, the third extension conductor 43, the fifth extension conductor 45, and the seventh extension conductor 47 may be extended from each corner of the rectangular coil when viewed from the stacking direction. Furthermore, the first land 51, the third land 53, the fifth land 55, and the seventh land 57 may be in direct contact with the first external electrode 21 at each ridge portion of the laminate 10 when viewed from the stacking direction.

[0109] In the laminated coil component 1C, the internal electrode may have, in addition to the second lead conductor 42 and the fourth lead conductor 44, a sixth lead conductor and an eighth lead conductor that are connected to the second external electrode 22, similar to the fifth lead conductor 45 and the seventh lead conductor 47.

[0110] The sixth and eighth lead conductors may have the same configuration as the second lead conductor 42 and the fourth lead conductor 44, except that the positions of contact with the coil conductor 32 and the second external electrode 22 are different. That is, the sixth lead conductor may have at least one sixth land spaced apart from its sixth end on the second external electrode 22 side and in direct contact with the second external electrode 22. The eighth lead conductor may have at least one eighth land spaced apart from its eighth end on the second external electrode 22 side and in direct contact with the second external electrode 22. The second lead conductor 42, the fourth lead conductor 44, the sixth lead conductor, and the eighth lead conductor may be connected in parallel between the coil and the second external electrode 22.

[0111] Next, a fourth modified example of the laminated coil component of the present invention will be described.

[0112] Fig. 10 is a perspective view schematically showing a fourth modified example of the laminated coil component of the present invention. Fig. 11 is a side view schematically showing, in a see-through manner, an example of the internal structure of a laminate constituting the fourth modified example of the laminated coil component of the present invention.

[0113] 10 and 11 , the first external electrode 21 covers a part of the first end face 11 and a part of the first main surface 13 of the laminate 10. The second external electrode 22 covers a part of the second end face 12 and a part of the first main surface 13 of the laminate 10.

[0114] In the laminated coil component 1D, the first main surface 13 serves as a mounting surface.

[0115] In the laminated coil component 1D, the first end 41 a of the first extension conductor 41 is in direct contact with the portion of the first external electrode 21 that covers the first end surface 11 of the laminate 10. The first land 51 of the first extension conductor 41 is in direct contact with the portion of the first external electrode 21 that covers the first main surface 13 of the laminate 10.

[0116] The second end 42 a of the second extension conductor 42 is in direct contact with the portion of the second external electrode 22 that covers the second end surface 12 of the laminate 10. The second land 52 of the second extension conductor 42 is in direct contact with the portion of the second external electrode 22 that covers the first main surface 13 of the laminate 10.

[0117] Next, a fifth modified example of the laminated coil component of the present invention will be described.

[0118] Fig. 12 is a perspective view schematically showing a fifth modified example of the laminated coil component of the present invention. Fig. 13 is a side view schematically showing, in a see-through manner, an example of the internal structure of a laminate constituting the fifth modified example of the laminated coil component of the present invention.

[0119] The laminated coil component 1E shown in FIGS. 12 and 13 is an example of a laminated coil component in which the lamination direction is perpendicular to the mounting surface.

[0120] In the laminated coil component 1E, the first external electrode 21 covers a part of the first end face 11 and a part of the first main surface 13 of the laminate 10. In addition, the second external electrode 22 covers a part of the second end face 12 and a part of the first main surface 13 of the laminate 10.

[0121] In the laminated coil component 1E, the first main surface 13 serves as a mounting surface.

[0122] In the laminated coil component 1E, the stacking direction is the height direction T. The stacking direction of the laminate 10 and the coil axis A of the coil 30 are perpendicular to the first main surface 13, which serves as the mounting surface. The laminated coil component 1E has a so-called vertically wound structure.

[0123] The first lead conductor 41 and the second lead conductor 42 extend in the stacking direction. In the laminated coil component 1E, the first lead conductor 41 and the second lead conductor 42 extend in the height direction T.

[0124] The first end 41 a of the first extension conductor 41 is in direct contact with the portion of the first external electrode 21 that covers the first main surface 13 of the laminate 10. The first land 51 of the first extension conductor 41 is in direct contact with the portion of the first external electrode 21 that covers the first end surface 11 of the laminate 10.

[0125] The second end 42 a of the second extension conductor 42 is in direct contact with the portion of the second external electrode 22 that covers the first main surface 13 of the laminate 10. The second land 52 of the second extension conductor 42 is in direct contact with the portion of the second external electrode 22 that covers the second end surface 12 of the laminate 10.

[0126] [First Aspect of the Manufacturing Method of the Laminated Coil Component] Next, a manufacturing method of the laminated coil component of the present invention, which can manufacture the laminated coil component of the present invention described up to this point, will be described.

[0127] A first aspect of the method for manufacturing a laminated coil component of the present invention includes the steps of: preparing a laminate, the laminate being formed by stacking a plurality of insulating layers in a stacking direction and having internal electrodes; performing a barrel polishing process on the laminate; and forming external electrodes on the outer surfaces of the barrel-polished laminate, wherein the internal electrodes have first and second lead conductors each extending in the stacking direction, and the first lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer; in the step of preparing the laminate, one first end of both ends of the first lead conductor in the stacking direction is exposed from the laminate, and none of the lands of the first lead conductor spaced from the first end is exposed from the laminate; in the step of performing the barrel polishing process, the laminate is polished to expose at least one first land spaced from the first end from the laminate; and in the step of forming the external electrode, a first external electrode is formed so as to cover the first end and at least one first land exposed from the laminate.

[0128] Hereinafter, a first embodiment of the method for manufacturing the laminated coil component of the present invention will be described, taking as an example a method for manufacturing the laminated coil component 1 shown in FIG. 1 and the like.

[0129] <Magnetic material manufacturing process> First, Fe ２ O ３ ZnO, CuO and NiO are weighed out to give a predetermined ratio.

[0130] Next, these weighed materials and pure water are placed in a ball mill together with PSZ (partially stabilized zirconia) media, mixed, and then pulverized. The mixing and pulverization time is, for example, 4 hours or more and 8 hours or less.

[0131] The resulting pulverized product is then dried and then calcined at a calcination temperature of, for example, 700° C. to 800° C. for, for example, 2 hours to 5 hours.

[0132] In this manner, a powdered magnetic material, more specifically, a powdered magnetic ferrite material is produced.

[0133] The ferrite material is preferably a Ni--Cu--Zn based ferrite material.

[0134] In the Ni-Cu-Zn ferrite material, when the total amount is 100 mol%, Fe is ２ O ３ It is preferable that the content of Zn is 40 mol % or more and 49.5 mol % or less in terms of ZnO, Zn is 2 mol % or more and 35 mol % or less in terms of ZnO, Cu is 6 mol % or more and 13 mol % or less in terms of CuO, and Ni is 10 mol % or more and 45 mol % or less in terms of NiO.

[0135] The Ni-Cu-Zn ferrite material may further contain additives such as Co, Bi, Sn, and Mn.

[0136] The Ni—Cu—Zn ferrite material may further contain inevitable impurities.

[0137] <Green Sheet Manufacturing Process> First, a magnetic material, an organic binder such as a polyvinyl butyral resin, an organic solvent such as ethanol or toluene, and a plasticizer are mixed in a ball mill together with PSZ media, and then pulverized to prepare a slurry.

[0138] Next, the slurry is formed into a sheet of a predetermined thickness by a doctor blade method or the like, and then punched into a predetermined shape to produce a green sheet. The thickness of the green sheet is, for example, 20 μm or more and 30 μm or less. The shape of the green sheet is, for example, rectangular.

[0139] As the material for the green sheets, instead of a magnetic material, a non-magnetic material such as borosilicate glass material may be used, or a mixed material of a magnetic material and a non-magnetic material may be used.

[0140] <Conductive Pattern Forming Process> First, via holes are formed by irradiating predetermined locations on the green sheet with a laser.

[0141] Next, a conductive paste such as Ag paste is applied to the surface of the green sheet by screen printing or the like, filling the via holes. This forms via conductor patterns in the via holes of the green sheet, while forming coil conductor conductor patterns connected to the via conductor patterns on the surface. In this manner, a coil sheet is produced in which coil conductor conductor patterns and via conductor patterns are formed on the green sheet. The coil sheet is provided with a coil conductor conductor pattern corresponding to the coil conductor 32 shown in FIG. 2 and a via conductor pattern corresponding to the via conductor 33 shown in FIG. 2 (excluding via conductors 33e and 33f). Separately from the coil sheet, a via sheet is produced in which a via conductor pattern corresponding to the via conductors 33e and 33f shown in FIG. 2 and a land conductor pattern corresponding to the lands 35e and 35f shown in FIG. 2 are formed.

[0142] <Step of Producing Laminated Block> The coil sheets and via sheets are laminated in the lamination direction (length direction L) in the order shown in FIG. 2, and then thermocompression-bonded to produce a laminated block.

[0143] <Step of Slicing the Laminate Block to Form Laminates> First, the laminate block is cut into pieces of a predetermined size using a dicer or the like to produce individual chips (laminated bodies).

[0144] Next, the individual chips are fired at a firing temperature of, for example, 900° C. to 920° C. for, for example, 2 hours to 4 hours.

[0145] When the individual chips are fired, the green sheets of the coil sheet and via sheet become insulating layers.

[0146] Furthermore, when the individual chips are fired, the conductor patterns for the coil conductors, the conductor patterns for the via conductors, and the conductor patterns for the lands become coil conductors, via conductors, and lands, respectively, resulting in the creation of a coil in which multiple coil conductors stacked together with insulating layers are electrically connected via the via conductors.

[0147] As a result, a laminate is prepared, which is made up of a plurality of insulating layers stacked in the stacking direction and has internal electrodes. The internal electrodes have first and second lead conductors extending in the stacking direction, and the first and second lead conductors have via conductors penetrating the insulating layers and lands provided on the insulating layers.

[0148] The step of preparing a laminate in the first aspect of the method for manufacturing a coil component may include the above-mentioned <step of preparing a magnetic material>, <step of preparing a green sheet>, <step of forming a conductor pattern>, <step of preparing a laminate block>, and <step of singulating the laminate block to form a laminate>.

[0149] Fig. 14 is an exploded perspective view schematically showing an example of a laminate produced in the step of preparing a laminate in the first embodiment of the method for producing a coil component of the present invention. Fig. 15 is a side view schematically showing, in perspective, an example of the internal structure of the laminate produced in the step of preparing a laminate in the first embodiment of the method for producing a coil component of the present invention.

[0150] The laminate 10 shown in FIGS. 14 and 15 does not have rounded corners and ridges as compared to the laminate 10 shown in FIGS. 2 and 3.

[0151] In the process of preparing the laminate, of both ends of the first extension conductor 41 in the stacking direction, one first end 41a is exposed from the laminate, and of the lands 35e of the first extension conductor 41, none of the lands 35e separated from the first end 41a are exposed from the laminate 10. Similarly, for the second extension conductor 42, the second end 42a is exposed from the laminate, but none of the lands 35f separated from the second end 42a are exposed from the laminate 10.

[0152] <Step of Barrel Polishing the Laminate> In the step of barrel polishing the laminate, corners and ridges are rounded by barrel polishing the laminate.

[0153] FIG. 16 is a perspective side view schematically showing an example of the internal structure of the laminate after the step of performing barrel polishing in the first embodiment of the manufacturing method of the coil component of the present invention.

[0154] In the step of performing the barrel polishing process, the laminate 10 is polished to expose at least one first land 51 spaced apart from the first end 41 a from the laminate 10. In FIG. 16 , one first land 51 is exposed from the laminate 10.

[0155] In the first aspect of the method for manufacturing a coil component of the present invention, the ridges and corners of the laminate 10 may be rounded by barrel polishing, thereby exposing the first lands 51 from the rounded ridges of the laminate 10. The first lands 51 may be exposed from the laminate 10 by extending the time of the barrel polishing process from the usual time. Furthermore, the position or size of the first lands 51 themselves may be adjusted so that the first lands 51 are exposed from the laminate 10 during the barrel polishing process.

[0156] At least one second land 52 spaced apart from the second end 42 a of the second lead conductor 42 can also be exposed from the laminate 10 in a similar manner.

[0157] <Step of forming external electrodes> In the step of forming external electrodes, external electrodes are formed on the outer surfaces of the barrel-polished laminate. In the step of forming external electrodes, a first external electrode is formed so as to cover the first end and at least one first land exposed from the laminate. Also, a second external electrode is formed so as to cover the second end and at least one second land exposed from the laminate.

[0158] FIG. 17 is a perspective side view schematically showing an example of the internal structure of the laminate after the step of forming external electrodes in the first embodiment of the method for manufacturing a coil component of the present invention has been performed.

[0159] FIG. 17 is the same view as FIG.

[0160] The process of forming the external electrodes will be described below with reference to FIG.

[0161] First, a conductive paste layer is formed by applying a conductive paste, such as a paste containing Ag and glass frit, to the first end face 11 and the second end face 12 of the outer surface of the laminate 10 from which the coil is drawn.

[0162] Next, the conductive paste layer is baked to form the base electrodes of the external electrodes at a baking temperature of, for example, 800° C. to 820° C. The thickness of the base electrodes is, for example, 5 μm.

[0163] Then, a Ni-plated electrode and a Sn-plated electrode are formed in this order on the surface of the base electrode by electrolytic plating, etc. This forms the first external electrode 21 and the second external electrode 22, each having the base electrode, the Ni-plated electrode, and the Sn-plated electrode in this order.

[0164] Through the above process, the first external electrode 21 is formed so as to cover the first end 41 a and the first land 51 exposed from the laminate 10, and the first external electrode 21 is directly connected to the first end 41 a and the first land 51. Furthermore, the second external electrode 22 is formed so as to cover the second end 42 a and the second land 52 exposed from the laminate 10, and the second external electrode 22 is directly connected to the second end 42 a and the second land 52.

[0165] In this manner, the laminated coil component 1 is manufactured.

[0166] [Second Aspect of the Manufacturing Method of the Laminated Coil Component] Next, a second aspect of the manufacturing method of the laminated coil component of the present invention will be described.

[0167] A second aspect of the method for producing a laminated coil component of the present invention includes the steps of: preparing a laminate block, the laminate block being formed by stacking a plurality of insulating layers in a stacking direction and having internal electrodes; dividing the laminate block into individual laminates; and forming external electrodes on the laminates, wherein the internal electrodes have first and second lead conductors extending in the stacking direction, and the first lead conductors have via conductors penetrating the insulating layers and lands provided on the insulating layers. In the step of preparing the laminate block, Of the two ends in the stacking direction, one first end is exposed from the laminate block, and none of the lands of the first extraction conductor that are spaced apart from the first end are exposed from the laminate, and in the process of dividing the laminate block, the laminate block is cut to expose at least one first land that is spaced apart from the first end from the laminate, and in the process of forming the external electrode, a first external electrode is formed to cover the first end and at least one of the first lands exposed from the laminate.

[0168] An example of the second embodiment of the method for producing a laminated coil component of the present invention will now be described.

[0169] A laminate block may be prepared by carrying out the same steps as those up to the <Laminate Block Fabrication Step> described in the first embodiment of the method for manufacturing a laminated coil component of the present invention, except that the structure of the laminate block is as shown in Fig. 18 described below. This makes it possible to prepare a laminate block having internal electrodes formed by stacking a plurality of insulating layers in the stacking direction. The internal electrodes have first and second lead conductors that extend in the stacking direction, and the first lead conductors have via conductors that penetrate the insulating layers and lands that are provided on the insulating layers.

[0170] FIG. 18 is a perspective view schematically showing an example of a laminate block produced in the step of preparing a laminate block in the second embodiment of the method for producing a laminated coil component of the present invention, as seen from the stacking direction.

[0171] The laminate block 110 shown in Fig. 18 becomes four laminates after being singulated. Fig. 18 shows cutting lines X and Y when singulating the laminate block 110 to form the laminates. In Fig. 18, the number of laminates included in the laminate block 110 is four, but the number of laminates included in the laminate block 110 is not particularly limited as long as it is two or more.

[0172] The coil 30 before firing is provided inside the laminate block 110. Of both ends of the first lead conductor 41 in the lamination direction, one first end 41a is exposed from the laminate block 110.

[0173] 18, a first land pattern 151 corresponding to the first land is provided so as to cross the cutting line X and the cutting line Y. The first land pattern 151 corresponding to the first land is present inside the laminate block 110 and is not exposed from the laminate block 110. In the laminate block 110, among the lands of the first extraction conductor 41, none of the lands spaced apart from the first end 41 a are exposed from the laminate.

[0174] 18 is cut along cutting lines X and Y with a dicer or the like to form a laminate. This exposes first land patterns 151 corresponding to the first lands from the cut surfaces of the laminate. That is, in the step of dividing the laminate block 110 into individual pieces, the laminate block 110 is cut to expose at least one first land spaced apart from the first end 41 a from the laminate.

[0175] Next, the individual chips are fired at a firing temperature of, for example, 900° C. to 920° C. for, for example, 2 hours to 4 hours.

[0176] When the individual chips are fired, the green sheets of the coil sheet and via sheet become insulating layers.

[0177] Furthermore, when the individual chips are fired, the conductor patterns for the coil conductors, the conductor patterns for the via conductors, and the conductor patterns for the lands become coil conductors, via conductors, and lands, respectively, resulting in the creation of a coil in which multiple coil conductors stacked together with insulating layers are electrically connected via the via conductors.

[0178] As a result, a laminate is prepared, which includes multiple insulating layers stacked in the stacking direction and has internal electrodes. The internal electrodes have first and second extension conductors extending in the stacking direction, and the first and second extension conductors have via conductors penetrating the insulating layers and lands provided on the insulating layers. At this stage, a first end of the first extension conductor and a first land spaced from the first end are exposed from the laminate, and a second end of the second extension conductor and a second land spaced from the second end are exposed from the laminate.

[0179] <Step of Barrel Polishing the Laminate> In the second aspect of the method for producing a laminated coil component of the present invention, the laminate may or may not be subjected to barrel polishing. By barrel polishing the laminate, corners and ridges can be rounded.

[0180] <Step of forming external electrodes> In the step of forming external electrodes, external electrodes are formed on the outer surfaces of the barrel-polished laminate. In the step of forming external electrodes, a first external electrode is formed so as to cover the first end and at least one first land exposed from the laminate. Also, a second external electrode is formed so as to cover the second end and at least one second land exposed from the laminate.

[0181] First, a conductive paste such as a paste containing Ag and glass frit is applied to the first end face and second end face from which the coil is drawn out of the outer surface of the laminate, thereby forming a conductive paste layer.

[0182] Next, the conductive paste layer is baked to form the base electrodes of the external electrodes at a baking temperature of, for example, 800° C. to 820° C. The thickness of the base electrodes is, for example, 5 μm.

[0183] Then, a Ni-plated electrode and a Sn-plated electrode are formed in this order on the surface of the base electrode by electrolytic plating, etc. This forms a first external electrode and a second external electrode each having the base electrode, the Ni-plated electrode, and the Sn-plated electrode in this order.

[0184] Through the above process, a first external electrode is formed to cover the first end and first lands exposed from the laminate, and the first external electrode 21 is directly connected to the first end and first lands. Also, a second external electrode is formed to cover the second end and second lands exposed from the laminate, and the second external electrode is directly connected to the second end and second lands.

[0185] In this manner, the laminated coil component of the present invention is manufactured.

[0186] The present specification discloses the following:

[0187] <1> A laminated coil component comprising: a laminate formed by stacking a plurality of insulating layers in a stacking direction and having an internal electrode; and a first external electrode and a second external electrode provided on an outer surface of the laminate, wherein the internal electrode has a first lead conductor extending in the stacking direction and connected to the first external electrode, and a second lead conductor extending in the stacking direction and connected to the second external electrode, wherein the first lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer, and wherein, of both ends of the first lead conductor in the stacking direction, one that is in direct contact with the first external electrode is defined as a first end, and the first external electrode is in direct contact with at least one first land of the lands of the first lead conductor that is spaced from the first end, in addition to the first end.

[0188] <2> The laminated coil component according to <1>, wherein the first external electrode is in direct contact with two or more of the first lands in addition to the first end.

[0189] <3> The laminated coil component according to <1> or <2>, wherein the first lead conductor has two or more lands, and the two or more lands of the first lead conductor include a land between the first end and the first land that does not contact the first external electrode.

[0190] <4> The laminated coil component according to any one of <1> to <3>, wherein the second lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer, and when one of both ends of the second lead conductor in the stacking direction that is in direct contact with the second external electrode is defined as a second end, the second external electrode is in direct contact with at least one second land, among the lands of the second lead conductor, that is spaced from the second end, in addition to the second end.

[0191] <5> The laminated coil component according to <4>, wherein the via conductor of the first lead conductor is present at the first end, and the land of the second lead conductor is present at the second end.

[0192] <6> The laminated coil component according to any one of <1> to <5>, wherein the internal electrode has a third lead conductor extending in the stacking direction and connected to the first external electrode, the third lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer, and when one of both ends of the third lead conductor in the stacking direction that is in direct contact with the first external electrode is defined as a third end, the first external electrode is in direct contact with at least one third land, among the lands of the third lead conductor, that is spaced from the third end, in addition to the third end.

[0193] <7> The laminated coil component according to any one of <1> to <6>, wherein the laminate is a substantially hexahedron, and all of the first lands are in direct contact with the first external electrodes at ridges of the laminate.

[0194] <8> The laminated coil component according to any one of <1> to <7>, wherein the lamination direction is parallel to the mounting surface.

[0195] <9> The laminated coil component according to any one of <1> to <7>, wherein the lamination direction is perpendicular to the mounting surface.

[0196] <10> A method for manufacturing a laminated coil component, comprising: preparing a laminate formed by stacking a plurality of insulating layers in a stacking direction and having internal electrodes; performing barrel polishing on the laminate; and forming external electrodes on an outer surface of the barrel-polished laminate, wherein the internal electrodes have first and second lead conductors each extending in the stacking direction, and the first lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer, wherein in the step of preparing the laminate, one first end of both ends of the first lead conductor in the stacking direction is exposed from the laminate, and none of the lands of the first lead conductor spaced from the first end is exposed from the laminate, wherein in the step of performing barrel polishing, the laminate is polished to expose at least one first land spaced from the first end from the laminate, and wherein in the step of forming the external electrode, a first external electrode is formed to cover the first end and at least one first land exposed from the laminate.

[0197] <11> A method for manufacturing a laminated coil component, comprising: a step of preparing a laminate block, the laminate block being formed by stacking a plurality of insulating layers in a stacking direction and having internal electrodes; a step of dividing the laminate block into individual pieces to form laminates; and a step of forming external electrodes on the laminate, wherein the internal electrodes have first and second lead conductors each extending in the stacking direction, and the first lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer, wherein in the step of preparing the laminate block, one first end of both ends of the first lead conductor in the stacking direction is exposed from the laminate block, and none of the lands of the first lead conductor spaced from the first end is exposed from the laminate, wherein in the step of dividing the laminate block, the laminate block is cut to expose at least one first land spaced from the first end from the laminate, and wherein in the step of forming the external electrodes, a first external electrode is formed so as to cover the first end and at least one first land exposed from the laminate.

[0198] REFERENCE SIGNS LIST 1, 1A, 1B, 1C, 1D, 1E Multilayer coil component 10 Laminate 11 First end face 12 Second end face 13 First main surface 14 Second main surface 15 First side face 16 Second side face 21 First external electrode 22 Second external electrode 30 Coil 31, 31a, 31b, 31c, 31d, 31e, 31f Insulating layer 32, 32a, 32b, 32c, 32d Coil conductor 33, 33a, 33b, 33c, 33d, 33e, 33f Via conductor 34, 34a, 34b, 34c, 34d Winding portion 35, 35a, 35b, 35c, 35d, 35e, 35e2, 35f, 35f2 Land 41 First lead conductor 41a First end 42 Second lead conductor 42a Second end 43 Third lead conductor 43a Third end 44 Fourth lead conductor 44a Fourth end 45 Fifth lead conductor 47 Seventh lead conductor 51 First land 52 Second land 53 Third land 54 Fourth land 55 Fifth land 57 Seventh land 110 Laminated block 151 First land pattern A Coil axis of coil

Claims

1. A laminated body in which a plurality of insulating layers are laminated in a lamination direction and which has internal electrodes, and a first external electrode and a second external electrode provided on an outer surface of the laminated body, wherein the internal electrodes include a first lead conductor that extends in the lamination direction and is connected to the first external electrode, and a second lead conductor that extends in the lamination direction and is connected to the second external electrode, the first lead conductor has a via conductor that penetrates the insulating layer and a land provided on the insulating layer, and when a side that directly contacts the first external electrode among both ends of the first lead conductor in the lamination direction is defined as a first end, the first external electrode directly contacts at least one first land spaced apart from the first end among the lands of the first lead conductor in addition to the first end. A laminated coil component.

2. The laminated coil component according to claim 1, wherein the first external electrode directly contacts two or more of the first lands in addition to the first end.

3. The first lead conductor has two or more of the lands, and two or more of the lands of the first lead conductor include a land that does not contact the first external electrode between the first end and the first land. The laminated coil component according to claim 1 or 2.

4. The second lead conductor has a via conductor that penetrates the insulating layer and a land provided on the insulating layer, and when a side that directly contacts the second external electrode among both ends of the second lead conductor in the lamination direction is defined as a second end, the second external electrode directly contacts at least one second land spaced apart from the second end among the lands of the second lead conductor in addition to the second end. The laminated coil component according to any one of claims 1 to 3.

5. The laminated coil component according to claim 4, wherein the via conductor of the first lead conductor is present at the first end, and the land of the second lead conductor is present at the second end.

6. The internal electrode extends in the stacking direction and has a third lead conductor connected to the first external electrode. The third lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer. When one of the two ends of the third lead conductor in the stacking direction that is in direct contact with the first external electrode is defined as the third end, the first external electrode is in direct contact with at least one third land spaced apart from the third end among the lands of the third lead conductor in addition to the third end. The stacked coil component according to any one of claims 1 to 5.

7. The stacked body is a substantially hexahedron, and all the first lands are in direct contact with the first external electrode at the ridge line portion of the stacked body. The stacked coil component according to any one of claims 1 to 6.

8. The stacking direction is parallel to the mounting surface. The stacked coil component according to any one of claims 1 to 7.

9. The stacking direction is perpendicular to the mounting surface. The stacked coil component according to any one of claims 1 to 7.

10. A step of preparing a stacked body in which a plurality of insulating layers are stacked in the stacking direction and has internal electrodes; a step of performing a barrel polishing process on the stacked body; and a step of forming an external electrode on the outer surface of the barrel-polished stacked body. The internal electrode has a first lead conductor and a second lead conductor each extending in the stacking direction. The first lead conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer. In the step of preparing the stacked body, one of the two ends of the first lead conductor in the stacking direction, i.e., the first end, is exposed from the stacked body, and none of the lands of the first lead conductor spaced apart from the first end are exposed from the stacked body. In the step of performing the barrel polishing process, the stacked body is polished to expose at least one first land spaced apart from the first end from the stacked body. In the step of forming the external electrode, a first external electrode is formed so as to cover the first end and at least one of the first lands exposed from the stacked body. A method for manufacturing a stacked coil component.

11. A step of preparing a laminated body block having a plurality of insulating layers laminated in a lamination direction and having internal electrodes; a step of fragmenting the laminated body block into individual pieces to form a laminated body; and a step of forming external electrodes on the laminated body, wherein the internal electrodes have a first lead-out conductor and a second lead-out conductor each extending in the lamination direction, the first lead-out conductor has a via conductor penetrating the insulating layer and a land provided on the insulating layer, in the step of preparing the laminated body block, one of the two ends of the first lead-out conductor in the lamination direction is exposed from the laminated body block, and none of the lands of the first lead-out conductor spaced apart from the first end are exposed from the laminated body, in the step of fragmenting the laminated body block, the laminated body block is cut to expose at least one first land spaced apart from the first end from the laminated body, and in the step of forming the external electrodes, a first external electrode is formed so as to cover the first end and at least one of the first lands exposed from the laminated body. A method for manufacturing a laminated coil component.

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