JP2019033179A - Coil component - Google Patents

Abstract

To provide a coil component capable of suppressing a short circuit between winding portions even when the thickness of a plurality of winding portions is increased.SOLUTION: A coil component 1 includes a first winding portion 211 wound along a plane, a first insulating portion 22 covering the first winding portion 211, a second insulating portion 23 laminated with respect to the first insulating portion 22, a second winding portion 241 laminated with respect to the second insulating portion 23 and wound along the plane, a third insulating portion 242 covering the second winding portion 241, and a via conductor 25 provided in a through hole penetrating through the first insulating portion 22 and the second insulating portion 23 and electrically connecting the first winding portion 211 and the second winding portion 241.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a coil component.

  Patent Document 1 describes an electronic component. This electronic component includes a laminated body in which a plurality of insulator layers are laminated, and a plurality of coil conductor layers laminated together with the insulator layers. An insulator layer is disposed between the plurality of coil conductor layers.

JP 2014-207280 A

  By the way, in the coil components as described above, it is considered to increase the thickness of the winding portion in order to reduce the wiring resistance. However, if the thickness of the winding portion is increased while maintaining the size of the coil component, the ratio of the thickness of the insulating layer to the thickness of the winding portion is reduced. For this reason, the flatness of an insulating layer may fall by shrinkage | contraction accompanying the hardening of the resin material which comprises an insulating layer. In such a case, there is a concern about a short circuit between the winding portions.

  The present invention has been made in view of the above, and provides a coil component capable of suppressing a short circuit between winding portions even when the thickness of a plurality of winding portions is increased. Objective.

  In order to solve the above problems, a coil component according to an aspect of the present invention includes a first winding portion wound along a plane, a first insulating portion covering the first winding portion, and a first winding portion. A second insulating portion stacked on the insulating portion; a second winding portion stacked on the second insulating portion and wound along a plane; and a third insulating portion covering the second winding portion And a via conductor provided in a through hole penetrating the first insulating portion and the second insulating portion and electrically connecting the first winding portion and the second winding portion.

  The coil component includes a first insulating portion that covers the first winding portion, and a second insulating portion that is stacked on the first insulating portion. Thereby, even when the thickness of the first winding part is large and the flatness of the first insulating part is lowered, the unevenness of the first insulating part is filled with the second insulating part, and the first insulating part and the first insulating part 2 The flatness of the entire insulating portion can be maintained. Therefore, even when the thickness of the first winding portion is increased, it is possible to suppress a short circuit between the first winding portion and the second winding portion.

  In the coil component according to an aspect, the second insulating portion may be interposed between the first insulating portion and the via conductor and may contact the first winding portion. According to this configuration, since the contact area between the second insulating portion and the via conductor is increased, the adhesion between the second insulating portion and the via conductor can be improved. Further, since the second insulating portion is in contact with the first winding portion, the second insulating portion and the first winding portion can be bonded. Therefore, it is possible to suppress damage as a coil component.

  In the coil component according to an aspect, the through hole includes a first through hole formed in the first insulating portion and a second through hole formed in the second insulating portion, and intersects the stacking direction. The dimension of the 2nd through-hole in may increase as it goes to the 1st coil part side from the 2nd coil part side. According to this configuration, since the size of the second through hole on the first through hole side is large, it is easy to form a portion where the first through hole and the second through hole overlap each other when viewed from the stacking direction. Therefore, the first winding portion and the second winding portion can be reliably connected by the via conductor.

  In the coil component according to an aspect, the through hole includes a first through hole formed in the first insulating portion and a second through hole formed in the second insulating portion, and intersects the stacking direction. The minimum dimension of the second through hole may be larger than the minimum dimension of the first through hole in the intersecting direction. Also in this configuration, it is easy to form a portion where the first through hole and the second through hole overlap each other when viewed from the stacking direction. Therefore, the first winding portion and the second winding portion can be reliably connected by the via conductor.

  ADVANTAGE OF THE INVENTION According to this invention, even if it is a case where the thickness of a coil | winding part is enlarged, the coil component which can suppress the fall of the flatness of an insulating layer is provided.

It is a perspective view which shows the coil components which concern on one Embodiment of this invention. It is sectional drawing along the II-II line of FIG. FIG. 2 is a partially exploded perspective view of the coil component of FIG. 1. FIG. 3 is an enlarged view schematically showing a structure near a via conductor of the coil component of FIG. 2. It is a figure for demonstrating the manufacturing method of the coil components of FIG. It is a figure for demonstrating the manufacturing method of the coil components of FIG. It is a figure for demonstrating the manufacturing method of the coil components of FIG. It is a figure for demonstrating the manufacturing method of the coil components of FIG. It is sectional drawing which shows roughly the coil components which concern on a modification. FIG. 10 is an enlarged view schematically showing a structure near a via conductor of the coil component of FIG. 9.

  Hereinafter, various embodiments will be described in detail with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

  The configuration of the coil component 1 will be described with reference to FIGS. FIG. 1 is a perspective view showing a coil component according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a partially exploded perspective view of the coil component 1 of FIG. In addition, in FIG. 3, illustration of the coating | coated part 7 mentioned later is abbreviate | omitted.

  A coil component 1 shown in FIG. 1 is a component mounted on, for example, a switching power supply circuit unit that performs voltage conversion of a DC voltage. As shown in FIGS. 1 to 3, the coil component 1 includes a magnetic substrate 10, a coil portion 20, a covering portion 7, conductor posts 19 </ b> A and 19 </ b> B, a cover insulating layer 30, and external terminals 40 </ b> A and 40 </ b> B. have.

  In this specification, the “stacking direction” refers to the magnetic substrate 10, the coil portion 20, the covering portion 7, the cover insulating layer 30, the external terminals 40 </ b> A and 40 </ b> B, and This is a direction in which the layers sequentially overlap. In the following description, the external terminals 40A and 40B side may be described as “upper” along the stacking direction, and the magnetic substrate 10 side may be described as “lower” along the stacking direction.

  The coil portion 20 is covered with the covering portion 7. The covering portion 7 has a rectangular parallelepiped outer shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape in which corner portions and ridge line portions are chamfered, and a rectangular parallelepiped shape in which corner portions and ridge line portions are rounded. The covering portion 7 has a main surface 7a, and the main surface 7a has a rectangular shape having a long side and a short side. The covering portion 7 is laminated on the magnetic substrate 10 and covers the periphery of the coil portion 20. The coating | coated part 7 is a mixture containing a magnetic filler and binder resin (resin). The constituent material of the magnetic filler is, for example, iron, carbonyl iron, silicon, chromium, nickel, or boron. The constituent material of the binder resin is, for example, an epoxy resin. The ratio of the magnetic filler contained in the covering portion 7 is, for example, 80% by weight or more of the entire covering portion 7. The average particle diameter of the magnetic filler is, for example, about 1 μm to 30 μm.

  The magnetic substrate 10 is a flat substrate made of a magnetic material such as ferrite. The magnetic substrate 10 is located on the side opposite to the main surface 7 a of the covering portion 7 (below the covering portion 7). A cover insulating layer 30 is laminated on the main surface 7a. External terminals 40 </ b> A and 40 </ b> B are provided on the insulating cover layer 30.

  The coil unit 20 includes a lower insulating layer B1, a first planar coil 21 including a first winding unit 211 and a first insulating unit 22, a second insulating unit 23, a second winding unit 241 and a third insulating unit. 242 including the second planar coil 24, the upper insulating layer B <b> 2, the first winding portion 211 and the second winding portion 241, and the connecting portion 26. .

  The lower insulating layer B1 is stacked on the magnetic substrate 10. The lower insulating layer B1 is provided on the entire surface of the magnetic substrate 10. A first planar coil 21 is stacked on the lower insulating layer B1.

  The first planar coil 21 has an axis A orthogonal to the main surface 7a of the magnetic substrate 10 and the covering portion 7, and has a rectangular ring shape. The first planar coil 21 includes a first winding part 211 wound in a rectangular shape with the axis A as a center, and a first insulating part 22 that covers the first winding part 211. Here, the first insulating portion 22 “covers the first winding portion 211” means that the main surface 211 a on at least one side (the upper side, that is, the second insulating portion 23 side) of the first winding portion 211, and the main A state in which the side surface of the first winding portion 211 continuous with the surface 211 a is in contact with the first insulating portion 22. The first winding portion 211 is laminated on the lower insulating layer B1, and the main surface on the lower side (magnetic substrate 10 side) of the first winding portion 211 is in contact with the lower insulating layer B1. The first winding part 211 is made of a metal material such as copper (Cu), for example.

  The first insulating part 22 includes two insulating layers 221 and 222. The insulating layer 221 fills the periphery of the first winding portion 211 in the same layer as the first winding portion 211. The insulating layer 221 fills the space between the winding portions of the first winding portion 211. The insulating layer 222 is in contact with the main surface 211 a on one side of the first winding portion 211. In the region of the first insulating portion 22 corresponding to the inner diameter of the coil portion 20, a through hole penetrating the first insulating portion 22 in the stacking direction is formed. The first insulating portion 22 is provided with a first through hole 22a that penetrates the first insulating portion 22 in the stacking direction. The first through hole 22 a is formed in the insulating layer 222 of the first insulating portion 22. In this embodiment, the insulating layers 221 and 222 are integrally provided, but the insulating layer 221 and the insulating layer 222 may be provided as separate layers. Further, the first insulating part 22 may include a lower insulating layer B1.

  The second insulating part 23 is an insulating layer stacked on the first insulating part 22. The second insulating portion 23 is provided with a second through hole 23a that penetrates the second insulating portion 23 in the stacking direction. An opening is formed in the region of the first insulating portion 22 corresponding to the inner diameter of the coil portion 20.

  The second planar coil 24 is stacked on the second insulating portion 23. Similar to the first planar coil 21, the second planar coil 24 has a rectangular annular shape. The second planar coil 24 includes a second winding portion 241 wound in a rectangular shape with the axis A as a center, and a third insulating portion 242 that covers the second winding portion 241. Here, the third insulating portion 242 "covers the second winding portion 241" means that the main surface 241a and the main surface at least on one side (upper side, that is, the upper insulating layer B2 side) of the second winding portion 241. A state in which the side surface of the second winding portion 241 continuous with 241 a is in contact with the third insulating portion 242. The second winding portion 241 is stacked on the second insulating portion 23, and the main surface on the lower side (first insulating portion 22 side) of the second winding portion 241 is in contact with the second insulating portion 23. ing. The second winding portion 241 is made of a metal material such as copper (Cu), for example.

  The third insulating portion 242 includes two insulating layers 242A and 242B. The insulating layer 242A fills the periphery of the second winding portion 241 in the same layer as the second winding portion 241. The insulating layer 242A fills the space between the winding portions of the second winding portion 241. The insulating layer 242B covers the main surface 241a on one side (the upper side, that is, the upper insulating layer B2 side) of the second winding portion 241. In the region of the third insulating portion 242 corresponding to the inner diameter of the coil portion 20, a through hole penetrating the third insulating portion 242 in the stacking direction is formed. In this embodiment, the insulating layers 242A and 242B are integrally provided, but the insulating layers 242A and 242B may be provided as separate layers.

  The upper insulating layer B <b> 2 is laminated on the second planar coil 24. In the region of the upper insulating layer B2 corresponding to the inner diameter of the coil portion 20, a through hole penetrating the upper insulating layer B2 in the stacking direction is formed.

  The lower insulating layer B1, the first insulating portion 22, the second insulating portion 23, the third insulating portion 242, and the upper insulating layer B2 are made of an insulating resin. Examples of the insulating resin include polyimide and polyethylene terephthalate. The lower insulating layer B1, the first insulating portion 22, the second insulating portion 23, the third insulating portion 242, and the upper insulating layer B2 may be made of the same material or different materials. May be.

  The via conductor 25 is provided in a through hole (the first through hole 22a and the second through hole 23a) that penetrates the first insulating part 22 and the second insulating part 23. The via conductor 25 electrically connects the innermost winding portion of the first winding portion 211 and the innermost winding portion of the second winding portion 241. Thus, one coil is formed by the first planar coil 21 and the second planar coil. The via conductor 25 may be provided integrally with the second winding portion 241 as shown in FIG. The connecting portion 26 extends from the outer end portion of the first winding portion 211 to the main surface 7a side of the covering portion 7, and electrically connects the first winding portion 211 and the conductor post 19B.

  The pair of conductor posts 19A and 19B are made of, for example, copper (Cu), and extend in the stacking direction from both ends of the coil unit 20 in the crossing direction intersecting the stacking direction. The conductor post 19 </ b> A is connected to the outer end of the second winding portion 241. The conductor post 19A extends from the second winding portion 241 to the main surface 7a of the covering portion 7 so as to penetrate the upper insulating layer B2 and the covering portion 7, and is exposed to the main surface 7a. An external terminal 40A is provided at a position corresponding to the exposed portion of the conductor post 19A. The conductor post 19 </ b> A is connected to the external terminal 40 </ b> A by the conductor portion 31 in the through hole 31 a of the cover insulating layer 30. As a result, the outer end portion (one end portion of the coil portion 20) of the second winding portion 241 and the external terminal 40A are electrically connected via the conductor post 19A and the conductor portion 31.

  The conductor post 19 </ b> B is connected to the connecting portion 26. The conductor post 19B extends from the connecting portion 26 to the main surface 7a of the covering portion 7 so as to penetrate the upper insulating layer B2 and the covering portion 7, and is exposed to the main surface 7a. An external terminal 40B is provided at a position corresponding to the exposed portion of the conductor post 19B. The conductor post 19 </ b> B is connected to the external terminal 40 </ b> B by the conductor portion 32 in the through hole 32 a of the cover insulating layer 30. As a result, the outer end portion of the first winding portion 211 (the other end portion of the coil portion 20) and the external terminal 40B are electrically connected via the connecting portion 26, the conductor post 19B, and the conductor portion 32. ing.

  The external terminal 40A is along one short side of the main surface 7a, and the external terminal 40B is along the other short side of the main surface 7a. The external terminals 40A and 40B are separated from each other in the direction along the long side of the main surface 7a. The pair of external terminals 40A and 40B are both film-like and rectangular in plan view. The external terminals 40A and 40B are electrically connected to the conductor posts 19A and 19B, respectively. The external terminals 40A and 40B are made of a conductive material such as copper (Cu), for example. The external terminals 40A and 40B can be formed by plating, for example. The external terminals 40A and 40B may have a single layer structure or a stacked structure in which a plurality of layers are stacked.

  The insulating cover layer 30 is provided on the main surface 7a of the covering portion 7, and is located between the conductor posts 19A and 19B and the external terminals 40A and 40B in the stacking direction. The insulating cover layer 30 has through holes 31a and 32a at positions corresponding to the conductor posts 19A and 19B. Conductor portions 31 and 32 made of a conductive material such as copper (Cu) are provided in the through holes 31a and 32a. The insulating cover layer 30 is made of an insulating material, for example, an insulating resin such as polyimide or epoxy.

  Next, a structure near the via conductor 25 will be described in detail with reference to FIG. FIG. 4 is an enlarged view schematically showing a structure in the vicinity of the via conductor 25 of the coil component of FIG. As shown in FIG. 4, the dimension D23 of the second through hole 23a in the intersecting direction is smaller than the dimension D22 of the first through hole 22a in the intersecting direction. Further, when viewed from the stacking direction, the second through hole 23a is located inside the first through hole 22a. Therefore, the second insulating portion 23 has a portion extending along the stacking direction between the via conductor 25 and the first insulating portion 22. As described above, the second insulating portion 23 is interposed between the via conductor 25 and the first insulating portion 22 and is in contact with the main surface 211 a of the first winding portion 211. In other words, the second insulating portion 23 overlaps the first insulating portion 22 around the via conductor 25. In other words, the second insulating portion 23 is disposed between the first insulating portion 22 and the via conductor 25, and the first insulating portion 22 and the via conductor 25 are separated from each other.

  As an example, the dimension D22 of the first through hole 22a in the intersecting direction is, for example, about 100 μm to 150 μm, and the dimension D23 of the second through hole 23a in the intersecting direction is, for example, about 80 μm to 130 μm. The ratio of the total thickness T of the first insulating part 22 and the second insulating part 23 to the thickness T211 of the first winding part 211 is, for example, 1.04 to 1.4. As an example, the thickness T21 of the first winding portion 211 is about 50 μm to 100 μm, the thickness of the insulating layer 222 of the first insulating portion 22 is about 2 μm to 10 μm, and the thickness of the second insulating portion 23 is about 2 μm to 10 μm. The thickness of the insulating layer 221 is about 50 μm to 100 μm.

  Next, with reference to FIGS. 5-8, the manufacturing method of the coil component 1 is demonstrated. 5-8 is a figure for demonstrating the manufacturing method of the coil component 1. FIG.

  First, the coil part 20 is formed on the magnetic substrate 10. Specifically, as shown in FIG. 5A, an insulating paste pattern is applied onto the magnetic substrate 10 and cured to form the lower insulating layer B1. Subsequently, as shown in FIG. 5B, a metal layer 14 is formed on the lower insulating layer B1. The metal layer 14 can be formed by plating or sputtering, for example. Then, the 1st coil | winding part 211 is formed by performing patterning using a predetermined mask. Subsequently, as shown in FIG. 5C, the first insulating portion 22 is formed. The first insulating portion 22 can be formed by applying and curing an insulating paste pattern on the metal layer 14. At this time, the insulating layer 221 and the insulating layer 222 of the first insulating portion 22 are formed at a time. Then, the 1st through-hole 22a is formed by etching the 1st insulating part 22 (insulating layer 222). As a result, the first planar coil 21 is formed.

  Subsequently, as shown in FIG. 6A, a second insulating portion 23 is formed by applying and curing an insulating resin paste pattern on the first insulating portion 22. At this time, the insulating resin paste is filled in the first through hole 22a. Next, the second through hole 23a for forming the via conductor 25 and the opening 16 for forming a part of the connecting portion 26 are formed. The second through hole 23a is formed inside the first through hole 22a when viewed from the stacking direction.

  Next, as shown in FIG. 6B, the metal layer 14 is formed again on the second insulating portion 23 by plating, sputtering, or the like. Then, the 2nd coil | winding part 241 is formed by performing patterning using a predetermined mask. At this time, the via conductor 25 is formed in the second through hole 23a. Further, a connecting portion 26 is formed at a position corresponding to the opening 16.

  Subsequently, as shown in FIG. 6C, the third insulating portion 242 and the upper insulating layer B2 are formed. The third insulating portion can be formed by applying and curing an insulating paste pattern on the metal layer 14 (second winding portion 241). At this time, the insulating layer 242A and the insulating layer 242B of the third insulating portion 242 are formed at a time. As a result, the second planar coil 24 is formed. Thereafter, the upper insulating layer B <b> 2 is formed on the third insulating portion 242.

  Next, as shown in FIG. 7A, the upper insulating layer B2 and the third insulating portion 242 are etched to form openings 19A 'and 19B' for forming the conductor posts 19A and 19B. Through the above steps, the coil portion 20 is formed.

  Next, as shown in FIG. 7B, portions of the metal layer 14 that do not constitute the first winding portion 211 and the second winding portion 241 (the first planar coil 21 and the second planar coil). The portion corresponding to the inner diameter portion and the outer peripheral portion of 24 is removed by etching or the like.

  Next, as shown in FIG. 7C, conductor posts 19A and 19B are formed. Specifically, seed portions are formed on the openings 19A ′ and 19B ′ of the insulating portion B4 by plating or sputtering using a predetermined mask, and the conductor posts 19A and 19B are formed by plating using the seed portions. . When the conductor posts 19A and 19B are formed by plating, for example, an insulating sacrificial layer (portion indicated by a two-dot chain line) can be used.

  Subsequently, as illustrated in FIG. 8A, a magnetic resin containing a magnetic filler and a resin is applied to the entire surface of the magnetic substrate 10, and a covering portion 7 is formed by performing a curing process. As a result, the conductor posts 19 </ b> A and 19 </ b> B are covered with the covering portion 7. At this time, the coating portion 7 is filled in the inner diameter portion of the coil portion 20.

  Next, as shown in FIG. 8B, the insulating cover layer 30 is formed by applying an insulating material such as an insulating resin paste on the main surface 7 a of the covering portion 7. When the insulating cover layer 30 is formed, the entire main surface 7a is covered, and through holes 31a and 32a are formed at positions corresponding to the pair of conductor posts 19A and 19B. 19B is exposed. Specifically, an insulating material is applied to the entire region of the main surface 7a, and thereafter, the cover insulating layer 30 at portions corresponding to the conductor posts 19A and 19B is removed.

  Next, a seed portion is formed on the cover insulating layer 30 in a region corresponding to the external terminals 40A and 40B by plating or sputtering using a predetermined mask. The seed portion is formed on the conductor posts 19A and 19B exposed from the through holes 31a and 32a of the insulating cover layer 30. Next, the external terminals 40A and 40B are formed by electroless plating using the seed portion. At this time, plating grows so as to fill the through holes 31a and 32a of the insulating cover layer 30, and the conductor portions 31 and 32 are formed. Through the above steps, the coil component 1 shown in FIG. 2 is formed.

  As described above, the coil component 1 according to this embodiment includes the first insulating portion 22 that covers the first winding portion 211 and the second insulating portion 23 that is stacked on the first insulating portion 22. Prepare. In general coil parts, if the thickness of the first winding part is increased while maintaining the size of the entire coil part, the ratio of the thickness of the insulating layer to the thickness of the first winding part is reduced. The flatness of the insulating layer may be reduced. On the other hand, since the coil component 1 includes two insulating layers of the first insulating portion 22 and the second insulating portion 23, the thickness of the first winding portion 211 is large, and the flatness of the first insulating portion 22 is high. Even if it falls, the unevenness | corrugation of the 1st insulating part 22 is filled with the 2nd insulating part 23, and the flatness of the whole 1st insulating part 22 and the 2nd insulating part 23 can be maintained. Therefore, even when the thickness T211 of the first winding portion 211 is increased, the short-circuit between the first winding portion 211 and the second winding portion 241 while maintaining the overall size of the coil component 1. Can be suppressed.

  In the coil component 1, the second insulating portion 23 is interposed between the first insulating portion 22 and the via conductor 25 and is in contact with the first winding portion 211. Thereby, since the contact area of the 2nd insulation part 23 and the via conductor 25 becomes large, the adhesiveness of the 2nd insulation part 23 and the via conductor 25 can be aimed at. Further, since the second insulating portion 23 is in contact with the first winding portion 211, the second insulating portion 23 and the first winding portion 211 can be bonded. Thus, the 1st insulating part 22 (insulating layer) located between the 2nd insulating part 23 and the 1st coil | winding part 211 by mutually bonding the 2nd insulating part 23 and the 1st coil | winding part 211 to each other. 222) can be prevented from being separated from the second insulating portion 23. Therefore, it is possible to suppress damage as the coil component 1.

  Next, a coil component 2 according to a modification will be described with reference to FIGS. FIG. 9 is a cross-sectional view schematically showing a coil component according to a modification. FIG. 10 is an enlarged view schematically showing the structure near the via conductor of the coil component of FIG. As shown in FIG. 9 and FIG. 10, the coil component 2 includes the first insulating portion 22 that covers the first winding portion 211 and the first insulating portion 22 stacked on the first insulating portion 22, as with the coil component 1. 2 insulating portions 23. The coil component 2 is different from the coil component 1 in that the minimum dimension of the second through hole 23a in the intersecting direction is larger than the minimum dimension of the first through hole 22a in the intersecting direction, and the via conductor 25 and the first insulation are different. The second insulating part 23 is not interposed between the part 22 and the part 22. The dimension D22 of the first through hole 22a and the dimension D23 of the second through hole 23a increase from the second winding part 241 side toward the first winding part 211 side.

  Next, a method for manufacturing the coil component 2 will be described. The coil component 2 is formed by the same process as the coil component 1 until the state where the first winding portion 211 is formed (the state shown in FIG. 5B). After forming the first winding part 211, the first insulating part 22 is formed on the first winding part 211. At this time, the first through hole 22a is formed in which the dimension D22 increases from the second planar coil 24 side toward the first planar coil 21 side. Such a first through hole 22a can be formed by adjusting conditions for etching the first insulating portion 22, for example. Next, plating is performed to form part of the via conductor 25 in the first insulating portion 22. Next, the second insulating part 23 is formed on the first insulating part 22. At this time, the second through hole 23a is formed in which the dimension D23 increases from the second winding part 241 side toward the first winding part 211 side. Thereafter, the second planar coil 24, the conductor posts 19A and 19B, the covering portion 7, the cover insulating layer 30, and the external terminals 40A and 40B are formed by the same process as the manufacturing method of the coil component 1. Through the above steps, the coil component 2 shown in FIG. 9 is formed.

  As described above, the coil component 2 also includes the first insulating portion 22 that covers the first winding portion 211 and the second insulating portion 23 that is stacked on the first insulating portion 22. Thereby, similarly to the coil component 1, even when the thickness of the first winding portion 211 is large and the flatness of the first insulating portion 22 is lowered, the first insulating portion 22 is caused by the second insulating portion 23. The entire flatness of the first insulating portion 22 and the second insulating portion 23 can be maintained. Therefore, even when the thickness T211 of the first winding portion 211 is increased, the short-circuit between the first winding portion 211 and the second winding portion 241 while maintaining the overall size of the coil component 1. Can be suppressed.

  In the coil component 2, the dimension D23 of the second through hole 23a in the intersecting direction intersecting the stacking direction increases from the second winding part 241 side toward the first winding part 211 side. Thereby, since the dimension D23 of the 2nd through-hole 23a in the 1st through-hole 22a side is large, seeing from a lamination direction, it becomes easy to form the part which the 1st through-hole 22a and the 2nd through-hole 23a mutually overlap. That is, it becomes easy to align the second through hole 23a with respect to the first through hole 22a. Therefore, the first winding part 211 and the second winding part 241 can be reliably connected by the via conductor 25.

  In the coil component 2, the minimum dimension of the second through hole 23a in the crossing direction intersecting the stacking direction is larger than the minimum dimension of the first through hole 22a in the crossing direction. Also in this structure, it is easy to form a portion where the first through hole 22a and the second through hole 23a overlap each other when viewed from the stacking direction. Therefore, the first winding part 211 and the second winding part 241 can be reliably connected by the via conductor 25.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to said embodiment, A various change can be made. For example, in the above-described embodiment, the example in which the coil unit 20 includes two winding units (the first winding unit 211 and the second winding unit 241) has been described. However, the coil unit 20 includes three or more coil units. You may have a coil | winding part. For example, when the coil part 20 further includes a third winding part laminated on the second winding part 241, the first insulating part is also provided between the second winding part 241 and the third winding part. Two insulating layers corresponding to the 22 insulating layers 222 and the second insulating portion 23 may be provided.

  The coil component 1 may include a magnetic resin layer formed of a magnetic resin made of the same material as that of the covering portion 7 instead of the magnetic substrate 10. In this case, the magnetic resin layer can be formed by applying the magnetic resin to the surface exposed by removing the magnetic substrate 10 after removing the magnetic substrate 10 of the coil component 1 by polishing or mechanical peeling. .

  DESCRIPTION OF SYMBOLS 1 ... Coil component, 10 ... Magnetic board | substrate, 211 ... 1st winding part, 22 ... 1st insulation part, 22a ... 1st through-hole, 23 ... 2nd insulation part, 23a ... 2nd through-hole, 241 ... 2nd Winding portion, 242... Third insulating portion, 25 .. via conductor, D22, D23.

Claims (4)

A first winding section wound along a plane;
A first insulating portion covering the first winding portion;
A second insulating part stacked on the first insulating part;
A second winding portion that is laminated with respect to the second insulating portion and wound along a plane;
A third insulating portion covering the second winding portion;
A coil component comprising: a via conductor provided in a through-hole penetrating the first insulating portion and the second insulating portion, and electrically connecting the first winding portion and the second winding portion. .   2. The coil component according to claim 1, wherein the second insulating portion is interposed between the first insulating portion and the via conductor and is in contact with the first winding portion. The through hole includes a first through hole formed in the first insulating portion, and a second through hole formed in the second insulating portion,
The dimension of the said 1st through-hole and the said 2nd through-hole in the cross | intersection direction which cross | intersects a lamination direction becomes large as it goes to the said 1st coil | winding part side from the said 2nd coil | winding part side. Coil parts. The through hole includes a first through hole formed in the first insulating portion, and a second through hole formed in the second insulating portion,
4. The coil component according to claim 1, wherein a minimum dimension of the second through hole in the crossing direction intersecting the stacking direction is larger than a minimum dimension of the first through hole in the crossing direction.

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