Coil component, coil component production method, and electronic / electrical apparatus

Abstract

A coil component 100 according to the present invention, which is capable of simultaneously achieving a decrease in size of the coil component and stability of coil shape comprises a coil conductor part 20, which includes a first spiral conductor part 11 and a second spiral conductor part 21 that each have a spiral shape as seen in a first direction and that are side by side in the first direction and a via part VP that electrically connects an inner-peripheral-side end part 12 of the first spiral conductor part 11 and an inner-peripheral-side end part 22 of the second spiral conductor part 21, and which has a conduction path from an outer-peripheral-side end part 13 of the first spiral conductor part 11, through the via part VP, and to an outer-peripheral-side end part 23 of the second spiral conductor part 21. The coil conductor part 20 has a first conductor part 11A, 21A which extends along the conduction path and which comprises a first conductive material, and a second conductor part 11B, 21B which comprises a second conductive material and which covers at least part of the first conductor part 11A. The second conductor part 11B is provided to at least part of a first end part 11F of the first spiral conductor part 11 on the side opposite from the second spiral conductor part 21.

Description

Coil component, coil component manufacturing method, and electronic / electrical equipment

[0001] The present invention relates to a coil component, a method for manufacturing the same, and an electronic / electrical device in which the coil component is mounted.

[0002] Patent Document 1 discloses a coil component comprising a main body including a coil including a top coil and a bottom coil connected to each other through vias, and an external electrode arranged on the outer surface of the main body and connected to the coil, wherein a first insulating layer is arranged on the surface of the top coil and a second insulating layer is arranged on the surface of the bottom coil, and the first and second insulating layers are arranged to extend between the top coil and the bottom coil.

[0003] As a method for manufacturing the above coil component, a method is disclosed that includes the steps of preparing an insulating film, processing via holes that penetrate the insulating film, arranging a conductive layer along the surface of the insulating film including the upper and lower surfaces of the insulating film and the via holes, arranging a patterned insulating wall on the conductive layer, filling the openings of the patterned insulating wall with a plating layer, removing the insulating wall and the conductive layer arranged between the insulating wall and the insulating film, removing the insulating film, and forming an insulating layer that covers the entire exposed surface.

[0004] US Patent Application Publication No. 2020 / 0027643

[0005] In the manufacturing method disclosed in Patent Document 1, the thickness of the insulating film determines the spacing between the top coil and the bottom coil. Because the insulating film, together with the insulating wall, forms the negative pattern of the top coil and the bottom coil, excessive thinning of the insulating film reduces the shape stability of the negative pattern, resulting in instability of the coil shape. Therefore, the insulating film must be thick enough to ensure a certain level of rigidity. However, the spacing between the top coil and the bottom coil, set based on this thickness, becomes dead space in the coil component and hinders miniaturization. Therefore, in the manufacturing method disclosed in Patent Document 1, miniaturization and stable coil shape are in a trade-off relationship in the built-in coil component.

[0006] An object of the present invention is to provide a coil component that can simultaneously achieve miniaturization and stability of the coil shape, a method for manufacturing such a coil component, and an electronic / electrical device in which such a coil component is mounted.

[0007] The inventors conducted research to solve the above problem and discovered that it is possible to narrow the gap between the top coil and the bottom coil by providing another conductor layer in the space created by removing the insulating layer.

[0008] Based on this finding, one aspect of the present invention provides a coil component comprising: a first spiral conductor portion and a second spiral conductor portion, both of which have a spiral shape when viewed in a first direction and are aligned in the first direction; a via portion electrically connecting an inner peripheral end of the first spiral conductor portion to an inner peripheral end of the second spiral conductor portion, the coil conductor portion having a conductive path from the outer peripheral end of the first spiral conductor portion to the outer peripheral end of the second spiral conductor portion via the via portion, the coil conductor portion having: a first conductor portion extending along the conductive path and made of a first conductive material; and a second conductor portion made of a second conductive material and covering at least a portion of the first conductor portion, the second conductor portion being provided on at least a portion of a first end of the first spiral conductor portion on a side facing the second spiral conductor portion. In such a coil component, the second conductor portion corresponds to the another conductive layer in the above finding.

[0009] In the above coil component, at least a portion of the turns of the first spiral conductor portion may have a first corner portion that connects the surface of the first end portion and the side surface along the first direction with a continuous surface.

[0010] In the manufacturing method disclosed in Patent Document 1, a coil is manufactured by disposing a conductive layer in an area surrounded by patterned insulating walls and insulating films. Therefore, when the insulating walls and insulating films that were in contact with the conductive layer are removed, the conductive layer that was in contact with the boundary between the insulating walls and the insulating film is likely to have sharp corners. An insulating layer is difficult to form at these corners, and even if formed, it is easily peeled off. Therefore, if the coil portion is covered with a material containing magnetic powder, there is a concern that direct contact between the magnetic powder and the coil will occur at the corners. Such direct contact can cause fatal defects in the component, such as short circuits within the coil component. Therefore, as described above, instead of directly forming an insulating layer on the conductive layer (first conductor portion) that was in contact with the boundary between the insulating walls and the insulating film, by covering the conductive layer (first conductor portion) with another conductive layer (second conductor portion) and then forming the insulating layer, the sharpness of the corners where the insulating layer will be formed is reduced, the formation of the insulating layer at the corners is stabilized, and the formed insulating layer is less likely to peel off.

[0011] When the above-mentioned coil component has a first corner, in a first cross section obtained by cutting along a plane passing through the first corner and along the first direction, the cross section line drawn by the first corner may have a shape such that the interface between the second conductor portion and a portion made of a conductive material located inside the second conductor portion approximates an arc with a larger radius of curvature than the cross section line drawn in the first cross section.

[0012] In the above coil component, a third conductor portion made of a third conductive material may be provided between the second conductor portion provided at the first end and the first conductor portion covered by the second conductor portion.

[0013] In the above coil component, the second conductor portion may be provided on at least a part of a second end portion of the second spiral conductor portion on a side facing the first spiral conductor portion.

[0014] In the above coil component, at least some of the turns of the second spiral conductor preferably have a second corner that connects the surface of the second end and a side surface along the first direction with a continuous surface. In this case, in a second cross section obtained by cutting the coil component along a surface that passes through the second corner and extends along the first direction, a cross section line drawn by the second corner may have a shape that approximates a circular arc with a larger radius of curvature than the cross section line drawn by the interface between the second conductor and a portion made of a conductive material located inside the second conductor in the second cross section.

[0015] When the above-mentioned coil component has a second corner portion, it may have a third conductor portion made of a third conductive material between the second conductor portion provided at the second end portion and the first conductor portion covered by the second conductor portion.

[0016] In the above coil component, at least one of the first spiral conductor and the second spiral conductor may have two turns aligned in a direction intersecting the first direction, and may include a first insulating portion covering at least a portion of two opposing side surfaces of the two turns. The first insulating portion corresponds to the insulating layer in the above knowledge.

[0017] When the above-mentioned first insulating part is provided, the first insulating part has a portion that contacts one of the two turns, a portion that contacts the other of the two turns, and a first connecting part that is connected to these portions and extends in a direction that intersects the first direction, and the first connecting part may have a thin portion that is thinner in the first direction than the portion of the first insulating part that contacts either of the two turns.

[0018] When the above-mentioned first insulating portion is provided, the first insulating portion may have an intervening portion located between a turn of the first spiral conductor portion and a turn of the second spiral conductor portion, and the intervening portion may have at least one of a boundary surface and a pore.

[0019] When the above-mentioned first insulating portion is provided, the first insulating portion may be present so as to cover each of the two opposing side surfaces of the two turns, and at least one of a line boundary and a closed space may be present between these first insulating portions.

[0020] In the case where the first insulating portion is provided, a second insulating portion made of a material different from the material constituting the first insulating portion may be located at least partially between the first spiral conductor portion and the second spiral conductor portion. In this case, a third conductor portion made of a third conductive material may be provided between the second conductor portion provided at the first end portion and the first conductor portion covered by the second conductor portion.

[0021] The above-mentioned coil component may further include a main body portion containing magnetic powder and covering all parts of the coil conductor portion except for the two ends thereof, and external electrodes provided on the main body portion and electrically connected to the two ends of the coil conductor portion exposed from the main body portion.

[0022] In another aspect, the present invention provides an electronic or electric device incorporating the above-described coil component, wherein the coil component is connected to a substrate via the external electrodes. Examples of such electronic or electric devices include power supply units equipped with a power switching circuit, a voltage step-up / step-down circuit, a smoothing circuit, etc., and small portable communication devices. The electronic or electric device according to the present invention is excellent in terms of quality and dimensions because it includes the above-described coil component.

[0023] In another aspect, the present invention provides a method for manufacturing a coil component including a coil conductor including a first spiral conductor portion and a second spiral conductor portion, both of which have a spiral shape when viewed in a first direction and are aligned in the first direction, and a via portion electrically connecting an inner peripheral end of the first spiral conductor portion to an inner peripheral end of the second spiral conductor portion, the coil conductor portion having a conductive path from the outer peripheral end of the first spiral conductor portion to the outer peripheral end of the second spiral conductor portion via the via portion. The coil conductor portion includes a first conductor portion extending along the conductive path and made of a first conductive material, and a second conductor portion made of a second conductive material and covering at least a portion of the first conductor portion, the first conductor portion having a first portion corresponding to the first spiral conductor portion, a second portion corresponding to the second spiral conductor portion, and a third portion corresponding to the via portion. The manufacturing method includes forming the first portion on one main surface of an insulating sheet substrate having a through hole, forming the second portion on the other main surface of the sheet substrate, and forming the third portion inside the through hole; removing a portion of the sheet substrate that faces neither the first portion nor the second portion, and removing at least a portion of a first opposing portion whose surface of the first portion faces the second portion proximal to the second portion, and a second opposing portion whose surface of the second portion faces the first portion proximal to the first portion; and forming the second conductor portion so as to cover an exposed portion of a member made of a conductive material that includes the first conductor portion.

[0024] In the sheet substrate, at least a portion of a first opposing portion whose surface on the side of the first portion that is proximal to the second portion faces the second opposing portion, and a second opposing portion whose surface on the side of the second portion that is proximal to the first portion faces the second opposing portion are removed, so that a second conductor portion is formed in at least a portion of the portion consisting of the first opposing portion and the second opposing portion, thereby narrowing the separation distance in the first direction between the first spiral conductor portion and the second spiral conductor portion.

[0025] In this case, the corner of the second conductor portion formed to cover the corner where the surface of the first portion intersecting the first direction and the first opposing portion are connected has a shape that connects the surface along the first direction and the surface intersecting the first direction with a continuous surface, so that a layer of insulating material (first insulating portion) is easily formed at the corner of the second conductor portion, and the formed layer (first insulating portion) is not easily peeled off from the second conductor portion. Similarly, the corner of the second conductor portion formed to cover the corner where the surface of the second portion intersecting the first direction and the second opposing portion are connected has a shape that connects the surface along the first direction and the surface intersecting the first direction with a continuous surface, so that a layer of insulating material (first insulating portion) is easily formed at the corner of the second conductor portion, and the formed layer (first insulating portion) is not easily peeled off from the second conductor portion.

[0026] In the case where the second conductor portion is formed by plating as described above, the main surface of the sheet substrate may have a third conductor portion made of a third conductive material, the first conductor portion may be formed by electroplating in which current is passed through the third conductor portion, and the exposed portion where the second conductor portion is formed may have a portion made of the third conductor portion. In this case, the processed area of ​​the main surface of the sheet substrate in the electroplating process may include a negative pattern of an insulating layer formed on the third conductor portion, and before removing the sheet substrate, the insulating layer and portions of the third conductor portion that do not contact the first conductor portion may be removed. Furthermore, it may be preferable that the third conductive material have etching characteristics different from those of the first conductive material.

[0027] When the coil component has a third conductor portion as described above, the processing area of ​​the main surface of the sheet substrate in the electroplating process may include a pattern of the third conductor portion having a shape corresponding to the first portion and the second portion.

[0028] In the method for manufacturing a coil component described above, an insulating material constituting the sheet base may remain at least partially between the first portion and the second portion. In this case, the insulating material may have a portion in contact with the first portion and the second portion, or the sheet base may have a structure in which inorganic particles are dispersed in a matrix portion made of an organic material, and the insulating material may contain the inorganic particles.

[0029] In the above-described method for manufacturing a coil component, a first insulating portion may be formed so as to cover at least a portion of the second conductor portion.

[0030] According to the present invention, a coil component is provided that can simultaneously achieve miniaturization and a stable coil shape. When this coil component is mounted in an electronic or electric device, the quality of the electronic or electric device can be stabilized and the dimensions of the electronic or electric device can be reduced. Furthermore, according to the present invention, a method for manufacturing the above coil component is provided.

[0031] 5 is a perspective view conceptually illustrating the shape of a coil component according to an embodiment of the present invention. FIG. 6 is a diagram illustrating the structure of a coil conductor included in a coil component according to an embodiment of the present invention. FIG. 7 is an XY plan view illustrating the structure of a first spiral conductor included in a coil component according to an embodiment of the present invention. FIG. 8 is an XY plan view illustrating the structure of a second spiral conductor included in a coil component according to an embodiment of the present invention. FIG. 9 is an XZ cross-sectional view taken along line A-A' in FIG. 2. FIG. 5 is a partial enlarged view of FIG. 6. FIG. 7 is a partial enlarged view of FIG. 8. FIG. 9 is an explanatory diagram of a detailed structure (first specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. FIG. 10 is an explanatory diagram of a detailed structure (second specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. FIG. 11 is an explanatory diagram of a detailed structure (third specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. FIG. 12 is an explanatory diagram of a detailed structure (fourth specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. FIG. 13 is an explanatory diagram of a detailed structure (variant 1 of the second specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. FIG. 1 is an explanatory diagram of a detailed structure (variant example 3 of the second specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention; FIG. 2 is an XZ cross-sectional view for explaining a variant example of a second conductor portion included in a coil component according to an embodiment of the present invention; FIG. 3 is an explanatory diagram (part 3) of an example of a method for manufacturing a coil component according to an embodiment of the present invention; FIG. 4 is an explanatory diagram (part 5) of an example of a method for manufacturing a coil component according to an embodiment of the present invention;

[0032] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0033] FIG. 1 is a perspective view conceptually illustrating the shape of a coil component according to an embodiment of the present invention. FIG. 2 is a diagram illustrating the structure of a coil conductor included in a coil component according to an embodiment of the present invention. For convenience of explanation, in FIG. 2, the coil conductor is depicted with a solid line, the main body is depicted with a dashed line, and other components are not shown. FIG. 3 is an XY plan view illustrating the structure of a first spiral conductor included in a coil component according to an embodiment of the present invention. FIG. 4 is an XY plan view illustrating the structure of a second spiral conductor included in a coil component according to an embodiment of the present invention. Note that FIG. 3 illustrates the coil conductor as viewed from the Z1 side in the Z1-Z2 direction, and FIG. 4 illustrates the coil conductor as viewed from the Z2 side in the Z1-Z2 direction.

[0034] (Overall Configuration) A coil component 100 according to one embodiment of the present invention includes a coil portion 10 having a coil conductor portion 20 , a main body portion 30 , a first external electrode 41 , a second external electrode 42 , and exterior coatings 50 and 60 .

[0035] (Coil) As shown in Figures 2 and 3, the coil portion 10 has a coil conductor portion 20 including a first spiral conductor portion 11 having a spiral shape around an axis O along a first direction (Z1-Z2 direction), from an inner circumferential end 12, which is the inner circumferential end of the first spiral conductor portion 11, toward an outer circumferential end 13, which is the outer circumferential end of the first spiral conductor portion 11. In Figure 2, the first spiral conductor portion 11 has conductors arranged in a spiral shape that moves away from the axis O in a clockwise direction from the inner circumferential end 12 toward the outer circumferential end 13, as viewed from the Z1 side in the Z1-Z2 direction. In this specification, the "spiral direction" of the first spiral conductor portion 11 means the direction from the inner circumferential end 12 toward the outer circumferential end 13. The same applies to a second spiral conductor portion 21, which will be described later.

[0036] The conductor (conductive material) constituting the coil conductor portion 20 is not limited as long as it has appropriate conductivity. Specific examples of the conductor constituting the coil conductor portion 20 include metals such as copper, copper alloys, aluminum, and aluminum alloys. The coil conductor portion 20 can be manufactured using a film-forming technique such as plating. The coil portion 10 has an insulating coil insulation portion (not shown in FIGS. 1 to 4 ) on the surface of the coil conductor portion 20. This coil insulation portion ensures insulation between adjacent conductors in the coil conductor portion 20 (between the surfaces of the conductors facing each other). The coil insulation portion is made of, for example, a resin material. No coil insulation portion is provided at the ends of the two ends of the coil conductor portion 20 (the first lead-out portion end surface 14E and the second lead-out portion end surface 24E), and the coil portion 10 can be electrically connected to other components at these ends.

[0037] As shown in Figures 2 and 4, the coil conductor portion 20 has a second spiral conductor portion 21 arranged alongside the first spiral conductor portion 11 in the first direction. The second spiral conductor portion 21 has a spiral shape around an axis O along the first direction (Z1-Z2 direction), from an inner circumferential end portion 22, which is the inner circumferential end of the second spiral conductor portion 21, to an outer circumferential end portion 23, which is the outer circumferential end of the second spiral conductor portion 21, and moving away from the axis O. In the second spiral conductor portion 21, the conductor is arranged in a spiral shape moving away from the axis O in the opposite direction to the first spiral conductor portion 11 (counterclockwise in Figure 2), when viewed from the Z1 side in the Z1-Z2 direction. The average value of the separation distance in the first direction (Z1-Z2 direction) between the first spiral conductor portion 11 and the second spiral conductor portion 21 is not particularly limited. The smaller this separation distance, the easier it is to reduce the height (dimension in the Z1-Z2 direction) of the coil component 100; however, if it is too small, the insulation between the first spiral conductor portion 11 and the second spiral conductor portion 21 is likely to decrease. From the viewpoint of achieving both a low profile (low height) of the coil component 100 and high insulation between the first spiral conductor portion 11 and the second spiral conductor portion 21, it is sometimes preferable that the separation distance be 0.4 μm or more and 20 μm or less. In order to reduce variation in the separation distance during manufacturing and to more reliably support the coil in the same plane, the separation distance is more preferably 1.0 μm or more, and even more preferably 5.0 μm or more.

[0038] The inner peripheral end 12 of the first spiral conductor portion 11 and the inner peripheral end 22 of the second spiral conductor portion 21 are electrically connected by a via portion VP. The via portion VP may be made of the same conductor as the coil conductor portion 20. In a specific example, the via portion VP is made of the same material as the first spiral conductor portion 11 and the second spiral conductor portion 21 and is manufactured simultaneously with the first spiral conductor portion 11 and the second spiral conductor portion 21. In this case, the via portion VP is integrated with the inner peripheral end 12 of the first spiral conductor portion 11 and the inner peripheral end 22 of the second spiral conductor portion 21.

[0039] A first lead portion 14 is connected to the outer peripheral end 13 of the first spiral conductor portion 11, and a second lead portion 24 is connected to the outer peripheral end 23 of the second spiral conductor portion 21. Therefore, the outer peripheral end 13 of the first spiral conductor portion 11 is essentially the interface with the first lead portion 14, and the outer peripheral end 23 of the second spiral conductor portion 21 is essentially the interface with the second lead portion 24. In a specific example, the first lead portion 14 and the second lead portion 24 are made of the same material as the first spiral conductor portion 11 and the second spiral conductor portion 21, and are manufactured simultaneously with the first spiral conductor portion 11 and the second spiral conductor portion 21. In this case, the first lead-out portion 14 is seamlessly integrated with the outer peripheral end portion 13 of the first spiral conductor portion 11, and the second lead-out portion 24 is seamlessly integrated with the outer peripheral end portion 23 of the second spiral conductor portion 21.

[0040] That is, in this embodiment, the coil conductor portion 20 has the first spiral conductor portion 11 and the second spiral conductor portion 21, the via portion VP, and the first lead portion 14 and the second lead portion 24, which are formed from a common conductive material. As a result, the coil conductor portion 20 has a conductive path that runs from the outer peripheral end portion 13 of the first spiral conductor portion 11 through the first spiral conductor portion 11 to the inner peripheral end portion 12, through the via portion VP that contacts the inner peripheral end portion 12 to the inner peripheral end portion 22 of the second spiral conductor portion 21, and from the inner peripheral end portion 22 through the second spiral conductor portion 21 to the outer peripheral end portion 23 of the second spiral conductor portion 21.

[0041] 5 is a cross-sectional view (XZ cross-sectional view) taken along the XZ plane (the plane indicated by line AA' in FIG. 2) illustrating the structure of a coil portion included in a coil component according to one embodiment of the present invention. Note that elements other than the coil portion 10 are not shown in FIG. 5.

[0042] 5, each turn of the first spiral conductor portion 11 and each turn of the second spiral conductor portion 21 are positioned so as to be aligned in a first direction. The first spiral conductor portion 11 has a first inner circumference side turn 111 which is the turn located on the innermost circumference, a first outer circumference side turn 113 which is the turn located on the outermost circumference, and a first central turn 112 which is the turn located between them, and the second spiral conductor portion 21 has a second inner circumference side turn 211 which is the turn located on the innermost circumference, a second outer circumference side turn 213 which is the turn located on the outermost circumference, and a second central turn 212 which is the turn located between them.

[0043] The second inner turn 211 is located on the Z2 side in the Z1-Z2 direction of the first inner turn 111, the second outer turn 213 is located on the Z2 side in the Z1-Z2 direction of the first outer turn 113, and the second central turn 212 is located on the Z2 side in the Z1-Z2 direction of the first central turn 112. In the coil portion 10 shown in Figure 5, the second lead-out portion 24 is not located on the Z2 side in the Z1-Z2 direction of the outer peripheral end portion 13 of the first spiral conductor portion 11, and the first lead-out portion 14 is not located on the Z1 side in the Z1-Z2 direction of the outer peripheral end portion 23 of the second spiral conductor portion 21.

[0044] (First Conductor Portion, Second Conductor Portion) Fig. 6 is a partial enlarged view of the region surrounded by the dashed line in Fig. 5. Fig. 7 is a partial enlarged view of the region surrounded by the dashed line in Fig. 6.

[0045] As shown in Figures 5 and 6, the first spiral conductor portion 11 has a first conductor portion 11A made of a first conductive material and extending along a conductive path from the outer peripheral end portion 13 of the first spiral conductor portion 11 via the via portion VP to the outer peripheral end portion 23 of the second spiral conductor portion 21, and a second conductor portion 11B made of a second conductive material and covering at least a portion of the first conductor portion 11A.

[0046] As described below, in one example, the first conductor 11A and the second conductor 11B are manufactured by different manufacturing processes. In this case, even if the materials are the same (e.g., Cu, Cu alloys, or other Cu-containing materials), their structural characteristics, such as crystal structure, crystal orientation, and crystal growth direction, are different, making them distinguishable by cross-sectional observation, for example. In a specific example, the first conductor 11A is made of an electroplating deposit (electrolytic plating deposit), and the second conductor 11B is made of a plating deposit. In this case, the plating deposit may be an electroplating deposit or an electroless plating deposit. From the viewpoint of improving the controllability of the thickness of the second conductor 11B, it may be preferable that the plating deposit be an electroplating deposit.

[0047] In this embodiment, a third conductor 11C, as shown in FIG. 6 , is provided at the end of the first conductor 11A facing the second spiral conductor 21 in the first direction (Z1-Z2 direction) (the Z2 side in the Z1-Z2 direction). The third conductive material constituting the third conductor 11C is not limited. It may be the same as or different from the material constituting the first conductor 11A (e.g., a material containing Cu, such as Cu or a Cu alloy). From a manufacturing perspective (as a base film for electroplating), it may be preferable for the third conductor 11C to be composed of a material containing at least one of Ni and Cr. It may be preferable for the material constituting the first conductor 11A and the material constituting the third conductor 11C to have different etching characteristics. For example, if the first conductor 11A is composed of Cu and the third conductor 11C is composed of Ni, Ni can be etched with high selectivity depending on the etching conditions. The third conductor portion 11C may be in the form of a film, or may be made up of a laminated film of different materials.

[0048] In this embodiment, the second conductor portion 11B is provided so as to cover at least a portion, specifically the entirety, of the first end portion 11F of the first spiral conductor portion 11 on the side facing the second spiral conductor portion 21.

[0049] Similarly to the first spiral conductor 11, the second spiral conductor 21 also has a first conductor 21A extending along the conductive path and made of a first conductive material, and a second conductor 21B made of a second conductive material and covering at least a part of the first conductor 21A. In this embodiment, the second spiral conductor 21 further has a third conductor 21C (see FIG. 6) made of a third conductive material at the end of the first conductor 21A on the side facing the first spiral conductor 11 in the first direction (Z1-Z2 direction) (the Z1 side in the Z1-Z2 direction). In addition, the second conductor 21B is provided so as to cover at least a part, specifically the entirety, of a second end 21F of the second spiral conductor 21 on the side facing the first spiral conductor 11.

[0050] In this way, since the second conductor portion 11B is provided at the first end portion 11F and the second conductor portion 21B is provided at the second end portion 21F, the distance between the first spiral conductor portion 11 and the second spiral conductor portion 21 is shorter than the distance between the third conductor portion 11C and the third conductor portion 21C. In a case where the first conductor portion 11A is formed by electroplating and the third conductor portion 11C is a base layer for the electroplating, and the second conductor portion 21B is formed by electroplating and the third conductor portion 21C is a base layer for the electroplating, as described in Patent Document 1, the separation distance between the first spiral conductor portion 11 and the second spiral conductor portion 21 is equal to the separation distance between the third conductor portion 11C and the third conductor portion 21C. However, in this embodiment, the second conductor portion 11B is provided closer to the second spiral conductor portion 21 than the third conductor portion 11C, and the second conductor portion 21B is provided closer to the first spiral conductor portion 11 than the third conductor portion 21C, thereby shortening the separation distance between the first spiral conductor portion 11 and the second spiral conductor portion 21. This reduces dead space, making it easier to improve the characteristics of the coil component 100 and to miniaturize it.

[0051] 5, the first lead-out portion 14 and the second lead-out portion 24 also have first conductor portions 14A, 24A, second conductor portions 14B, 24B, and third conductor portions 14C, 24C, similar to the first spiral conductor portion 11 and the second spiral conductor portion 21. That is, the first conductor portions 14A, 11A, 21A, 24A extend along the conductive path of the coil conductor portion 20 from the first lead-out portion end face 14E through the first lead-out portion 14, the first spiral conductor portion 11, the via portion VP, the second spiral conductor portion 21, and the second lead-out portion 24 to the second lead-out portion end face 24E.

[0052] (First Corner Portion, Second Corner Portion) Fig. 7 is an enlarged view of the area surrounded by the dashed line in Fig. 6. Fig. 7 shows the inner periphery side and the first end portion 11F side of the first inner periphery side turn 111 (the Z2 side in the Z1-Z2 direction).

[0053] The first inner turn 111 has a first corner 11G that connects the surface 11FS of the first end 11F with a side surface along the first direction, specifically the inner surface 11SS, with a continuous surface. The inclusion of this first corner 11G allows the surface 11GS of the first corner 11G to be a smooth surface (a surface without sharp bends). Such a surface facilitates the formation of a first insulating portion 80 (described in detail below), making the formed first insulating portion 80 less likely to peel. Peeling of the first insulating portion 80 causes the magnetic powder contained in the main body 30 to come into direct contact with the first inner turn 111 (the first spiral conductor portion 11). If the magnetic powder contains metallic portions, such contact can cause a short circuit of the coil conductor portion 20 via the magnetic powder. Therefore, the coil component 100 according to this embodiment, which includes the first spiral conductor portion 11 having the first corner 11G, has excellent quality stability.

[0054] In a first cross section obtained by cutting along a plane passing through the first corner 11G and along the first direction, the cross section line drawn by the first corner 11G has a shape that approximates an arc with a larger radius of curvature than the cross section line drawn in the first cross section by an interface IF1 between the second conductor 11B and a portion consisting of the conductive material located inside the second conductor 11B (third conductor 11C in FIG. 7). The first cross section is typically a plane that includes the axis O and is orthogonal to the XY plane, and in the specific example shown in FIG. 7, the first cross section is an XZ cross section taken along line A-A' in FIG. The radius R of the arc approximated to the line formed by the surface 11GS of the first corner portion 11G has a center P on the bisector L1 of the angle defined by the line formed by the surface 11FS of the first end portion 11F and the line formed by the inner surface 11SS of the first inner turn 111, and is larger than the radius of the approximate arc similarly determined for the line formed by the interface IF1 between the portion made of conductive material located inside the second conductor portion 11B (specifically, the third conductor portion 11C) and the second conductor portion 11B.

[0055] Because the radius of the approximate arc is large in this manner, the surface (surface 11GS) on which the first insulating portion 80 is formed becomes a gentle surface, thereby stably reducing the possibility of short-circuiting of the coil conductor portion 20.

[0056] Although not shown in detail, as shown in FIG. 6 , at least some of the turns of the second spiral conductor 21 have a second corner 21G that connects the surface of the second end 21F and the side surface along the first direction with a continuous surface. Furthermore, in a second cross section obtained by cutting along a plane passing through this second corner 21G and along the first direction, the cross section line drawn by the second corner 21G has a shape that approximates an arc with a larger radius of curvature than the cross section line drawn by the interface between the second conductor 21B and a portion (third conductor 21C) made of a conductive material located inside the second conductor 21B. Like the first cross section, the second cross section is typically a plane that includes the axis O and is perpendicular to the XY plane. An example of the second cross section is the XZ cross section taken along line A-A' in FIG. 2 .

[0057] (First insulating portion) The coil insulating portion has a first insulating portion 80, and as shown in Figure 6, the first insulating portion 80 is provided on at least a portion of the surface of the first spiral conductor portion 11 and the surface of the second spiral conductor portion 21.

[0058] In this embodiment, the first insulating portion 80 is thermoplastic and contains a thermoplastic resin including a paraxylylene-based polymer. Other examples of the thermoplastic resin include polyethylene, polypropylene, polyamide, polyester, polyamideimide, polyimide, polysulfone, polycarbonate, liquid crystal polymer, polyvinylidene fluoride, and polytetrafluoroethylene. The first insulating portion 80 as a whole is only required to have thermoplastic properties, and may contain, in addition to the above-mentioned thermoplastic resin, for example, inorganic insulating particles.

[0059] The first insulating portion 80 preferably has excellent insulating properties, specifically, a volume resistivity of 1.0×10 obtained by ASTM D257. 14 In some cases, it is preferable that the volume resistivity is 1.0×10 Ωcm or more. 15 More preferably, it is 1.0×10 Ωcm or more. 16 The upper limit of the volume resistivity is not particularly limited. 20 The dielectric constant may be Ωcm or less. Furthermore, it is preferable that the first insulating part 80 has excellent dielectric properties. Specifically, it may be preferable that the dielectric constant at 60 Hz obtained by ASTM D150 is 4.0 or less. This dielectric constant is more preferably 3.5 or less, and even more preferably 3.0 or less. The upper limit of this dielectric constant is not particularly limited. The dielectric constant may be 1.0 or more. The method for measuring the volume resistivity and dielectric constant of the first insulating part 80 is not limited as long as results equivalent to those obtained by ASTM D257 and D150 are expected. For example, a measurement sample is separately prepared by preparing a material corresponding to the first insulating part 80 to the dimensions required for measurement, and this measurement sample is used to identify the constituent materials through analytical techniques such as component analysis and FT-IR, and the characteristics of the material, such as volume resistivity, are evaluated.

[0060] The first insulating portion 80 has a portion that contacts a portion of the first spiral conductor portion 11 opposite to the side facing the second spiral conductor portion 21, i.e., a portion (first opposite-direction portion 11FA) of the first spiral conductor portion 11 that is opposite to the second spiral conductor portion 21. In Fig. 6, the first inner circumferential turn 111, the first central turn 112, and the first outer circumferential turn 113, as well as the end portion on the Z1 side in the Z1-Z2 direction of the first lead-out portion 14 connected to the first outer circumferential turn 113, are the first opposite-direction portion 11FA, and the first insulating portion 80 is provided so as to contact this first opposite-direction portion 11FA.

[0061] The first insulating portion 80 has a portion that contacts an opposite-direction portion (second opposite-direction portion 21FA) of the second spiral conductor portion 21 relative to the first spiral conductor portion 11. In Fig. 6, the second opposite-direction portion 21FA is the end portion on the Z2 side in the Z1-Z2 direction of the second inner turn 211, the second central turn 212, and the second outer peripheral turn 213, and the first insulating portion 80 has a portion that contacts this second opposite-direction portion 21FA.

[0062] The first insulating portion 80 has a portion that contacts a side portion of the first spiral conductor portion 11 along the spiral direction. Specifically, the side portion is explained using the first inner circumferential turn 111. The first inner circumferential turn 111 has a side portion facing the inner circumferential side (the X1 side in the X1-X2 direction) and a side portion facing the outer circumferential side (the X2 side in the X1-X2 direction) and facing the first central turn 112. The first insulating portion 80 has a portion that contacts these side portions. The first insulating portion 80 is not provided on the end face (first lead-out portion end face 14E) on the outer circumferential side (the X2 side in the X1-X2 direction) of the outer circumferential end portion 13 of the first spiral conductor portion 11 so as to allow electrical connection to another member (the first external electrode 41).

[0063] The first insulating portion 80 has a portion that contacts a side portion of the second spiral conductor portion 21 along the spiral direction. Specifically, the side portion is explained using the second inner circumferential turn 211. The second inner circumferential turn 211 has a side portion facing the inner circumferential side (the X1 side in the X1-X2 direction) and a side portion facing the outer circumferential side (the X2 side in the X1-X2 direction) and facing the second central turn 212. The first insulating portion 80 has a portion that contacts these side portions. Although not shown, the first insulating portion 80 is not provided on a side surface (the second lead-out portion end surface 24E, see FIG. 5 ) on the outer circumferential side (the X1 side in the X1-X2 direction) of the outer circumferential end portion 23 of the second spiral conductor portion 21 so as to allow electrical connection to another member (the second external electrode 42).

[0064] From the viewpoint of stably realizing the provision of the first insulating portion 80 on the side portion, it may be preferable that the average width of the gap between two turns aligned in a direction (XY in-plane direction) intersecting the first direction (Z1-Z2 direction) be 0.025 to 0.25 times the average width of the two turns aligned in the alignment direction.

[0065] In order to ensure good insulation properties of the first insulating portion 80, it is preferable that the average value of the thickness of the portion of the first insulating portion 80 that contacts the first opposite-facing portion 11FA (the portion of the first spiral conductor portion 11 that faces the second spiral conductor portion 21), the thickness of the portion that contacts the second opposite-facing portion 21FA (the portion of the second spiral conductor portion 21 that faces the first spiral conductor portion 11), the thickness of the portion that contacts the side portion of the first spiral conductor portion 11, and the thickness of the portion that contacts the side portion of the second spiral conductor portion 21 is 0.2 μm or more and 10 μm or less. From the viewpoint of ensuring insulation properties more stably, this average value is more preferably 1.0 μm or more.

[0066] The first insulating portion 80 has a first connecting portion 801 located so as to connect a portion in contact with a side of a first turn, which is at least one of the turns of the first spiral conductor portion 11 (in this embodiment, the first inner circumferential turn 111, the first central turn 112, and the first outer circumferential turn 113), to a portion in contact with a side of a second turn that is nearest from the side of the first turn in the second spiral conductor portion 21. From the viewpoint of stable formation of the first connecting portion 801, it may be preferable that the average value of the separation distance in the first direction (Z1-Z2 direction) between the first spiral conductor portion 11 and the second spiral conductor portion 21 be 0.4 μm or more and 20 μm or less.

[0067] Taking the case where the first turn is the first inner turn 111 as a specific example, the second turn that is closest from the side of the first turn (first inner turn 111) in the second spiral conductor portion 21 is the second inner turn 211. The first insulating portion 80 that is positioned so as to connect the first insulating portion 80 that is in contact with the side of the first inner turn 111 on the inner side (X1 side in the X1-X2 direction) and the first insulating portion 80 that is in contact with the side of the second inner turn 211 on the inner side (X1 side in the X1-X2 direction) is the first connecting portion 801.

[0068] 6 further shows a first connecting portion 801 connecting the first insulating portion 80 in contact with the side portion of the outer periphery (X2 side in the X1-X2 direction) of the first inner turn 111 to the first insulating portion 80 in contact with the side portion of the outer periphery (X2 side in the X1-X2 direction) of the second inner turn 211, a first connecting portion 801 connecting the first insulating portion 80 in contact with the side portion of the inner periphery (X1 side in the X1-X2 direction) of the first central turn 112 to the first insulating portion 80 in contact with the side portion of the inner periphery (X1 side in the X1-X2 direction) of the second central turn 212, A first connecting portion 801 is shown connecting the first insulating portion 80 in contact with the side portion of the outer periphery (X2 side in the X1-X2 direction) of the first central turn 112 to the first insulating portion 80 in contact with the side portion of the outer periphery (X2 side in the X1-X2 direction) of the second central turn 212, and a first connecting portion 801 is shown connecting the first insulating portion 80 in contact with the side portion of the inner periphery (X1 side in the X1-X2 direction) of the first outer periphery turn 113 to the first insulating portion 80 in contact with the side portion of the inner periphery (X1 side in the X1-X2 direction) of the second outer periphery turn 213.

[0069] In this way, by having the first connection portion 801, it is possible to reduce the volume of the coil insulation portion, making it easier to improve the electrical characteristics of the coil component 100 and meet the demand for miniaturization of the coil component 100.

[0070] The first insulating portion 80 has a portion that contacts the portion of the first spiral conductor portion 11 facing the second spiral conductor portion 21 (first end 11F) and a portion that contacts the portion of the second spiral conductor portion 21 facing the first spiral conductor portion 11 (second end 21F). In the first insulating portion 80 shown in FIG. 6 , these portions are integrated to form an intervening portion 80i, and the intervening portion 80i and the first connecting portion 801 are integrated. In the intervening portion 80i, the first insulating portion 80 that contacts the portion of the first spiral conductor portion 11 facing the second spiral conductor portion 21 (first end 11F) also contacts the second spiral conductor portion 21 without a connection boundary. This configuration makes it easy to improve the insulation between the first spiral conductor portion 11 and the second spiral conductor portion 21.

[0071] The first insulating portion 80 in contact with the side portion of the outer periphery (X2 side in the X1-X2 direction) of the second outer periphery turn 213 has a third connecting portion 803 that connects the first insulating portion 80 in contact with the first extending portion 14P that is on the Z2 side of the first lead-out portion 14 in the Z1-Z2 direction and extends from the first end 11F of the first outer periphery turn 113, to the first insulating portion 80 in contact with the side portion of the outer periphery (X2 side in the X1-X2 direction) of the second outer periphery turn 213. The third connecting portion 803 is also provided between the first insulating portion 80 in contact with the side portion of the outer periphery (X1 side in the X1-X2 direction) of the first outer periphery turn 113 and the first insulating portion 80 in contact with the portion of the second lead-out portion 24 on the Z1 side in the Z1-Z2 direction.

[0072] The first insulating portion 80 shown in Fig. 6 comes into contact with a portion of the coil conductor portion 20 that is located inside the main body portion 30. Specifically, the first insulating portion 80 is provided so as to come into contact with a portion of the coil conductor portion 20 other than the end portion (first lead-out portion end surface 14E) on the outer side (X2 side in the X1-X2 direction) of the first lead-out portion 14 and the end portion (second lead-out portion end surface 24E, not shown in Fig. 6) on the outer side (X1 side in the X1-X2 direction) of the second lead-out portion 24. This reliably prevents a short circuit within the coil conductor portion 20 that would otherwise occur due to contact between the coil conductor portion 20 and the magnetic powder, even if the surface of the magnetic powder contained in the main body portion 30 is conductive.

[0073] From the viewpoint of more reliably preventing short circuits within the coil conductor 20, it is preferable that the first insulating portion 80 in contact with the first spiral conductor portion 11 be in continuous contact with the turn without any connection boundaries at the portion in contact with the facing portion (first end 11F) of the second spiral conductor portion 21, the portion in contact with the opposite portion (first opposite-facing portion 11FA) of the second spiral conductor portion 21, and the portion in contact with the side surface, for all turns of the first spiral conductor portion 11. Similarly, it is preferable that the first insulating portion 80 in contact with the second spiral conductor portion 21 be in continuous contact with the turn without any connection boundaries at the portion in contact with the facing portion (second end 21F) of the first spiral conductor portion 11, the portion in contact with the opposite portion (second opposite-facing portion 21FA) of the second spiral conductor portion 21, and the portion in contact with the side surface, for all turns of the second spiral conductor portion 21.

[0074] The detailed structure of the first insulating portion 80 in the first embodiment will be described below with reference to FIGS. 8 to 14, which correspond to the area surrounded by the dashed line in FIG. 6. That is, FIGS. 8 to 14 are all diagrams illustrating the detailed structure of the first insulating portion 80 in the first embodiment. In all of these figures, at least one of the first spiral conductor portion 11 and the second spiral conductor portion 21 has two turns aligned in the X1-X2 direction, which intersects with the first direction (the Z1-Z2 direction). Specifically, the first spiral conductor portion 11 has a first inner circumferential turn 111 and a first central turn 112, and the second spiral conductor portion 21 has a second inner circumferential turn 211 and a second central turn 212.

[0075] 8 is an explanatory diagram of a detailed structure (first specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. In the first specific example, a first insulating portion 80 that contacts one of two opposing side surfaces of two turns is in contact with a first insulating portion 80 that contacts the other of the two side surfaces, and two first connecting portions 801 present in the two turns are in contact with each other at a boundary surface 80b.

[0076] Specifically, the first insulating portion 811o in contact with the outer circumferential side (X2 side in the X1-X2 direction) of the first inner turn 111 has one contact portion with the first insulating portion 812i in contact with the inner circumferential side (X1 side in the X1-X2 direction) of the first central turn 112 that faces this side, and a boundary surface 80b exists at the contact portion, which is a line segment boundary. Similarly, the first insulating portion 821o in contact with the outer circumferential side (X2 side in the X1-X2 direction) of the second inner turn 211 has two contact portions with the first insulating portion 822i in contact with the inner circumferential side (X1 side in the X1-X2 direction) of the second central turn 212 that faces this side, and a boundary surface 80b exists at the contact portion. The two contact portions form a pore 80p, which is a closed space. Such boundary surfaces 80b and pores 80p can absorb displacement of the coil portion 10 when the coil portion 10 thermally expands due to heat generated when the coil component 100 is in operation, and can reduce stress applied to the magnetic powder in the main body 30 near the coil portion 10, which is prone to magnetic saturation. Therefore, the boundary surfaces 80b and pores 80p can improve the DC superimposed rated current of the electronic component.

[0077] Furthermore, a first connecting portion 801 is present for each of the first inner turn 111 and the first central turn 112, and these two first connecting portions 801 are in contact with each other at a boundary surface 80b. Note that an intervening portion 80i is present between the first inner turn 111 and the second inner turn 211, and an intervening portion 80i is also present between the first central turn 112 and the second central turn 212. Both of these intervening portions 80i are integrated with the first connecting portion 801.

[0078] 9 is an explanatory diagram of a detailed structure (second specific example) of a first insulating portion provided in a coil component according to an embodiment of the present invention. In the second specific example, the first insulating portion 80 that contacts one of the two opposing side surfaces of the two turns and the first insulating portion 80 that contacts the other of the two side surfaces are integrated, and the two first connecting portions 801 present in the two turns are integrated.

[0079] Specifically, the first insulating portion 811o, which contacts the side portion on the outer periphery (X2 side in the X1-X2 direction) of the first inner turn 111, has one portion integrated with the first insulating portion 812i, which contacts the side portion on the inner periphery (X1 side in the X1-X2 direction) of the first central turn 112 that faces this side portion, and this integrated portion is the fused portion 80f.

[0080] Furthermore, a first connecting portion 801 is present for each of the first inner turn 111 and the first central turn 112, and these two first connecting portions 801 are integrated with each other via a fusion portion 80f. Note that an intervening portion 80i is present between the first inner turn 111 and the second inner turn 211, and an intervening portion 80i is also present between the first central turn 112 and the second central turn 212. All of these intervening portions 80i are integrated with the first connecting portion 801.

[0081] That is, at least one of the two first connection portions 801 has at least one of a portion in contact with the portion facing the first spiral conductor portion 11 (first end portion 11F) and a portion in contact with the portion facing the second spiral conductor portion 21 (second end portion 21F). In Fig. 8, each of the two first connection portions 801 has a portion in contact with the portion facing the first spiral conductor portion 11 (first end portion 11F) and a portion in contact with the portion facing the second spiral conductor portion 21 (second end portion 21F).

[0082] 9, the first insulating part 80 includes two first connecting parts 801 each having a fused part 80f. The first connecting part 801 has a portion that contacts one of the two turns (e.g., the first inner turn 111), a portion that contacts the other of the two turns (the first central turn 112), and a second connecting part 802 (the area surrounded by a dotted line in FIG. 9) that is connected to these portions and extends in a direction (the X1-X2 direction in FIG. 9) that intersects the first direction (the Z1-Z2 direction). The second connecting part 802 is made up of the portion of the two first insulating parts 80 that includes the fused part 80f.

[0083] The second connecting portion 802 has a thin portion 80t that is thinner in the first direction (Z1-Z2 direction) than the portion of the first insulating portion 80 that contacts either of the two turns. It may be preferable that the ratio of the thickness Dt of the thin portion 80t in the first direction (Z1-Z2 direction) to the thickness of the other portion of the second connecting portion 802 in the first direction (Z1-Z2 direction) is 0.6 or more. In this case, the thin portion 80t forms a recess 80d, and it is easy to achieve a ratio of the depth of the recess 80d to the thickness of the other portion of the second connecting portion 802 in the first direction (Z1-Z2 direction) of 0.2 or less.

[0084] (Third Specific Example) Figure 10 is an explanatory diagram showing a detailed structure (third specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. The intervening portion 80i of the first insulating portion 80 shown in Figures 8 and 9 is provided integrally between the first spiral conductor portion 11 and the second spiral conductor portion 21 so as to contact both of them, but the intervening portion 80i shown in Figure 10 is not integrated. Specifically, the intervening portion 80i has an opposing contact portion 811f that contacts the first end portion 11F of the first inner turn 111 and an opposing contact portion 821f that contacts the second end portion 21F of the second inner turn 211, with a boundary surface 80b present between them. In addition, the interposed portion 80i has an opposing contact portion 812f that contacts the first end 11F of the first central turn 112 and an opposing contact portion 822f that contacts the second end 21F of the second central turn 212, and there is an interface 80b between them, and further, there are also pores 80p.

[0085] (Fourth Specific Example) FIG. 11 is an explanatory diagram of a detailed structure (fourth specific example) of a first insulating portion included in a coil component according to an embodiment of the present invention. In the fourth specific example, insulating particles 95, such as oxide-based particles, are present between the first spiral conductor portion 11 and the second spiral conductor portion 21. Specific examples of the insulating particles 95 include inorganic materials such as oxides, carbides, nitrides, and inorganic salts. Examples of oxides include silica, alumina, and zirconia. Examples of carbides and nitrides include silicon carbide and boron nitride, respectively. Examples of inorganic salts include silicates, phosphates, borates, and carbonates. Examples of such inorganic salts include minerals such as wollastonite, kaolin, and mica. Of these, oxide-based materials such as oxides, silicates, and phosphates are preferred in terms of insulating properties. For example, the insulating particles 95 preferably include at least one selected from the group consisting of silicon (Si), phosphorus (P), boron (B), and calcium (Ca). The shape of the insulating particles 95 is not particularly limited as long as they can be positioned between the first spiral conductor 11 and the second spiral conductor 21. The shape may be nearly spherical, a needle-like shape with a large aspect ratio, or an amorphous shape. When observing a cross section between the first spiral conductor 11 and the second spiral conductor 21, the average equivalent circle diameter of the insulating particles 95 may preferably be 0.0010 μm or more and 2.5 μm or less. This average equivalent circle diameter is more preferably 0.020 μm or more, and even more preferably 0.050 μm or more. Furthermore, the average equivalent circle diameter is more preferably 2.0 μm or less, and even more preferably 1.5 μm or less. From the viewpoint of contributing to ensuring insulation between the first spiral conductor 11 and the second spiral conductor 21 even during the manufacturing process of the coil component 100, the insulating particles 95 are preferably hard. From this viewpoint, too, the insulating particles 95 are preferably made of an inorganic material rather than an organic material.

[0086] 12 to 14 are explanatory diagrams showing detailed structures of a first insulating portion (Variations 1 to 3 of the second specific example) included in a coil component according to an embodiment of the present invention. In Variation 1 shown in Fig. 12, the fused portion 80f formed by the first connecting portion 801 extends between the side of the first inner turn 111 and the side of the first central turn 112 and between the side of the second inner turn 211 and the side of the second central turn 212. As a result, the second connecting portion 802 extends in the first direction (Z1-Z2 direction). Both ends of this second connecting portion 802 may extend to the first opposite-direction portion 11FA and the second opposite-direction portion 21FA (see Fig. 6), respectively. In Modification 2 shown in Figure 13, the amount of intervening portion 80i is smaller than in Modification 1, and there are portions at the first end 11F and the second end 21F that are not in contact with the first insulating portion 80. In Modification 3 shown in Figure 14, the first insulating portion 80 does not have a portion that contacts the first end 11F and the second end 21F. When the first insulating portion 80 is not present between the first end 11F and the second end 21F as in Figures 13 and 14, it is preferable to have insulating particles 95 instead of the first insulating portion 80 to prevent a short circuit between the first spiral conductor 11 and the second spiral conductor 21.

[0087] (Modification of Second Conductor Portion) Fig. 15 is an XZ cross-sectional view illustrating a modification of the second conductor portion included in the coil component according to one embodiment of the present invention, and corresponds to the XZ cross-sectional view shown in Fig. 6. In the modification shown in Fig. 15, the structures of the second conductor portions 11B and 21B located at the first end portion 11F and the second end portion 21F are different from those of the embodiment shown in Fig. 6, and the second conductor portions 11B and 21B do not cover a portion of the third conductor portions 11C and 21C.

[0088] Specifically, at the first end 11F of the first inner turn 111, the second insulating portion 90 is positioned so as to cover a portion of the third conductor portion 11C, and the second conductor portion 11B partially covers the portion of the third conductor portion 11C not covered by the second insulating portion 90 and the side portion of the second insulating portion 90 (the portion on the X1-X2 direction side in FIG. 15 ). At the second end 21F of the second inner turn 211, the second insulating portion 90 is positioned so as to cover a portion of the third conductor portion 21C, and the second insulating portion 90 is partially covered by the second conductor portion 21B. The second insulating portion 90 covering a portion of the first end 11F of the first inner turn 111 is integral with the second insulating portion 90 covering a portion of the second end 21F of the second inner turn 211, and insulating particles 95 are held in this second insulating portion 90. The second insulating portion 90 is in contact with a part of the second conductor portion 11 B. The first insulating portion 80 is positioned so as to cover the second insulating portion 90 and the insulating particles 95 .

[0089] At the first end 11F of the first central turn 112, the third conductor 11C is covered by the second conductor 11B, but at the second end 21F of the second inner turn 211, the second insulating portion 90 is positioned so as to cover part of the third conductor 11C, and the second conductor 11B is positioned so as to cover part of a side of the second insulating portion 90, just like the second end 21F of the second inner turn 211. The space between the first end 11F and the second end 21F is filled with the first insulating portion 80.

[0090] At the first end 11F of the first outer turn 113, insulating particles 95 are positioned so as to adhere to the third conductor 11C, and the second conductor 11B is positioned so as to cover the portion of the third conductor 11C not contacted by the insulating particles 95 and part of the side of the insulating particles 95. At the second end 21F of the second outer turn 213, the second insulating portion 90 is positioned so as to cover part of the third conductor 11C, and insulating particles 95 are attached to the first end 11F side of the second insulating portion 90. The second conductor 11B is positioned so as to cover the portion of the third conductor 11C not contacted by the second insulating portion 90, and this second conductor 11B also covers the second insulating portion 90 and is also in contact with the insulating particles 95. The space between the first end 11F and the second end 21F is filled with the first insulating portion 80.

[0091] In this manner, in this modification, a substance other than the first insulating portion 80 is located between the opposing first end portion 11F and second end portion 21F.

[0092] (Second insulating portion) In this modification, the second insulating portion 90 contacts at least one of the first spiral conductor portion 11 and the second spiral conductor portion 21. This ensures insulation of the first spiral conductor portion 11 and the second spiral conductor portion 21. Furthermore, since the second insulating portion 90 contacts both the first spiral conductor portion 11 and the second spiral conductor portion 21, a short circuit between the first spiral conductor portion 11 and the second spiral conductor portion 21 is reliably avoided.

[0093] The material constituting the second insulating portion 90 is not limited as long as it has appropriate insulating properties. The second insulating portion 90 has a volume resistivity of 1.0×10 14 In some cases, it is preferable that the volume resistivity is 1.0×10 Ωcm or more. 15 More preferably, it is 1.0×10 Ωcm or more. 16 The upper limit of the volume resistivity is not particularly limited. 20The dielectric constant may be Ωcm or less. Furthermore, it is preferable that the second insulating part 90 has excellent dielectric properties. Specifically, it may be preferable that the dielectric constant at 60 Hz obtained by ASTM D150 is 4.0 or less. This dielectric constant is more preferably 3.5 or less, and even more preferably 3.0 or less. The upper limit of this dielectric constant is not particularly limited. The dielectric constant may be 1.0 or more. The method for measuring the volume resistivity and dielectric constant of the second insulating part 90 is not limited as long as results equivalent to those obtained by ASTM D257 and D150 are expected. For example, a measurement sample is separately prepared by preparing a material corresponding to the second insulating part 90 to the dimensions required for measurement, and this measurement sample is used to identify the constituent materials through analytical techniques such as component analysis and FT-IR, and the characteristics of the material, such as volume resistivity, are evaluated.

[0094] The material constituting the second insulating portion 90 may be an organic material, an inorganic material, or a composite material of an organic material and an inorganic material. When the second insulating portion 90 is made of a composite material, the inorganic material may be in the form of particles dispersed in a matrix of an organic material. In this case, the inorganic material may be insulating particles 95. Specific examples of organic materials include polyimide resin, polyethylene resin, polypropylene resin, polyamide resin, polyester resin, polyamideimide resin, polysulfone resin, polycarbonate resin, liquid crystal polymer resin, polyvinylidene fluoride resin, and polytetrafluoroethylene resin. Specific examples of inorganic materials, particularly inorganic materials in composite materials, include inorganic materials such as oxides, carbides, nitrides, and inorganic salts. Examples of oxides include silica, alumina, and zirconia. Examples of carbides and nitrides include inorganic materials such as silicon carbide and boron nitride, respectively. Examples of inorganic salts include wollastonite, kaolin, mica, and other minerals. Among these, oxide-based materials such as oxides, silicates, and phosphates are preferred in terms of cost and insulating properties. For example, it is preferred that the inorganic material contains at least one element selected from the group consisting of silicon (Si), phosphorus (P), boron (B), and calcium (Ca).

[0095] (Main body portion) The main body portion 30 contains magnetic powder and contains a portion of the coil portion 10. In this embodiment, the main body portion 30 has a substantially rectangular parallelepiped shape and contains the portion of the coil portion 10 other than the first lead-out portion end face 14E and the second lead-out portion end face 24E located at the ends of the coil portion 10.

[0096] The structure of the magnetic powder is not limited. This structure may include a crystalline phase or an amorphous phase. Here, a crystalline material is defined as a material consisting of a crystalline phase, an amorphous material as a material consisting of an amorphous phase, and a composite material as a material consisting of a crystalline phase and an amorphous material. If the diffraction spectrum obtained by a general X-ray diffraction method includes a sharp diffraction peak that can identify the type of crystalline phase, the material contains a crystalline phase. Also, if the diffraction spectrum obtained by a general X-ray diffraction method includes a broad peak indicating an amorphous phase, the material contains an amorphous phase. If the DSC curve obtained by differential thermal analysis includes a peak indicating crystallization, i.e., heat generation associated with a phase change from an amorphous phase to a crystalline phase, the material also contains an amorphous phase.

[0097] The material system of the magnetic powder is not limited. Specific examples of crystalline materials include Fe—Si—Cr alloys, Fe—Ni alloys, Fe—Co alloys, Fe—V alloys, Fe—Al alloys, Fe—Si alloys, Fe—Si—Al alloys, pure iron, and ferrite. Carbonyl iron powder is preferred as pure iron powder. Specific examples of amorphous materials include Fe—Si—B alloys, Fe—P—C alloys, and Co—Fe—Si—B alloys. Specific examples of composite materials include Fe—Zr alloys, Fe—Zr—B alloys, Fe—Si—B—Nb—Cu alloys, and Fe—Si—B—P—Cu alloys. When the magnetic powder is a metal powder containing Fe, the synergistic effect of improving magnetic properties is particularly large.

[0098] The chemical composition of the magnetic powder is not limited. For example, an Fe—Si—Cr alloy may be composed of 1.0 to 10.0 mass% Si, 1.0 to 10.0 mass% Cr, and the balance consisting of Fe and impurities. Also, for example, an Fe—Ni alloy may be composed of 1.0 to 99.0 mass% Ni, and the balance consisting of Fe and impurities. Furthermore, for example, an Fe—P—C alloy may be composed of 1.0 to 13.0 atomic% P, 1.0 to 13.0 atomic% C, Fe, and impurities. This Fe—P—C alloy may contain one or more optional elements selected from the group consisting of Ni, Sn, Cr, B, and Si. In this case, for example, the amount of Ni may be 0 to 10.0 atomic %, the amount of Sn may be 0 to 3.0 atomic %, the amount of Cr may be 0 to 6.0 atomic %, the amount of B may be 0 to 9.0 atomic %, and the amount of Si may be 0 to 7.0 atomic %. The amount of Fe is preferably 65 atomic % or more. Furthermore, for example, the Fe-Si-B-Nb-Cu alloy may be composed of 1.0 to 16.0 atomic % Si, 1.0 to 15.0 atomic % B, 0.50 to 5.0 atomic % Nb, 0.50 to 5.0 atomic % Cu, and the balance consisting of Fe and impurities. In this case, the amount of Fe is preferably 65 atomic % or more.

[0099] The shape of the magnetic powder is not limited. The magnetic powder may be spherical, elliptical, scaly, or irregularly shaped. The manufacturing method for obtaining these shapes is also not limited.

[0100] The particle size distribution of the magnetic powder is not limited. The particle size distribution of the magnetic powder can be obtained, for example, by analyzing an image (secondary electron image) obtained by capturing an image of a cut surface of the main body 30 using a scanning electron microscope. For example, the average equivalent circle diameter of the magnetic powder may be 0.50 to 50.0 μm. The distribution of equivalent circle diameters may include multiple peaks.

[0101] The magnetic powder may be subjected to a surface insulating treatment. When the magnetic powder is subjected to a surface insulating treatment, the insulation resistance of the main body 30 is improved. The type of surface insulating treatment to be applied to the magnetic powder is not limited. Examples include phosphate treatment, phosphate salt treatment, and oxidation treatment. The magnetic powder may have an insulating coating on the surface of the magnetic particles. This insulating coating may contain at least one element selected from the group consisting of Si, P, and B, and O (oxygen).

[0102] The magnetic powder may be a mixture of a plurality of powder materials. The magnetic powder is preferably a ferromagnetic material, and more preferably a soft magnetic material.

[0103] The main body 30 may further contain an optional auxiliary material. The optional auxiliary material may be, for example, a binder material or a modifier. The binder material binds together particles of the magnetic powder and the like contained in the main body 30. This binder material is preferably an insulating material to impart insulation resistance to the main body 30.

[0104] The binder material may be an organic material or an inorganic material. The organic material may be a resin material. Examples of the resin material include acrylic resin, silicone resin, epoxy resin, phenol resin, urea resin, melamine resin, and polyester resin. The inorganic material may be a glass-based material such as water glass. The binder material may be a product of a reaction such as thermal decomposition, or may be a mixture of multiple materials.

[0105] The modifier improves the flowability of the powder, adjusts the hardening speed of the binder material, etc. The modifier may be a glass-based material.

[0106] There are no limitations on the dimensions of the main body 30. For example, the maximum dimension of the main body 30 may be 3.2 mm or less.

[0107] 2, the first lead-out portion end face 14E and the second lead-out portion end face 24E, which are located at the ends of the coil portion 10, are exposed from the main body portion 30 at side faces aligned in the X1-X2 direction of the main body portion 30. A first external electrode 41 is provided so as to be in electrical contact with the first lead-out portion end face 14E, and a second external electrode 42 is provided so as to be in electrical contact with the second lead-out portion end face 24E.

[0108] 1, the first external electrode 41 has a side surface portion 41a covering the side surface of the main body 30 on the X2 side in the X1-X2 direction, and a bottom surface portion 41b provided so as to cover a portion of the bottom surface (the surface on the Z2 side in the Z1-Z2 direction) of the main body 30. The bottom surface portion 41b faces the substrate during use. The second external electrode 42 has a side surface portion 42a covering the side surface of the main body 30 on the X1 side in the X1-X2 direction, and a bottom surface portion 42b provided on the bottom surface of the main body 30 so as to cover a portion of the bottom surface while being spaced apart from the bottom surface portion 41b. The bottom surface portion 42b also faces the substrate during use.

[0109] The positions of the first external electrode 41 and the second external electrode 42 are not limited to the above positions. The first external electrode 41 and the second external electrode 42 may be formed so as to cover a portion of the top surface (the surface on the Z1 side in the Z1-Z2 direction) of the main body 30. Alternatively, the first external electrode 41 and the second external electrode 42 may be provided on only a portion of the bottom surface (the surface on the Z2 side in the Z1-Z2 direction) of the main body 30. In this case, the coil conductor 20 may have connection conductors (not shown) that connect the two ends of the coil 10 (the first lead 14, the second lead 24) to the bottom surface of the main body 30 through the inside of the main body 30. In this case, the two ends of the coil 10 (the first lead end surface 14E, the second lead end surface 24E) may not be exposed to the side surfaces of the main body 30, and the connection conductors may be exposed to the bottom surface of the main body 30.

[0110] The materials and configurations of the first external electrode 41 and the second external electrode 42 are not limited as long as they have appropriate conductivity. One non-limiting example of the first external electrode 41 and the second external electrode 42 is a layer having a Cu-plated / Ni-plated / Sn-plated structure from the side proximal to the surface of the main body 30. The first external electrode 41 and the second external electrode 42 may be formed as a coated electrode in which a conductive material such as silver is dispersed in a resin or the like. Alternatively, the first external electrode 41 and the second external electrode 42 may be a combination of a plated electrode and a coated electrode.

[0111] (External Coating) An insulating external coating 50, 60 is provided on the top surface (the surface on the Z1 side in the Z1-Z2 direction) of the main body 30 and on the side surfaces aligned in the Y1-Y2 direction. An insulating external coating may also be provided on the bottom surface of the main body 30 in a portion where the bottom surface portions 41b, 42b are not provided. Furthermore, the coil device 100 may not be provided with the external coating 50, 60. The external coatings 50, 60 can be formed at any position on the surface of the main body 30 depending on the purpose.

[0112] (Manufacturing Method) There are no particular limitations on the method for manufacturing the coil component 100 according to this embodiment. One non-limiting example of the manufacturing method is as follows.

[0113] 16 to 20 are explanatory diagrams (parts 1 to 5) of an example of a method for manufacturing a coil component according to an embodiment of the present invention.

[0114] (a) Preparation of Sheet Base Material First, a sheet base material 91 is prepared, having a base material through-hole 91H provided at a position corresponding to the via portion VP, as shown in Figure 16(a). There are no material restrictions on the sheet base material 91, as long as it has the mechanical properties necessary to function as a support when forming the first spiral conductor portion 11 and the second spiral conductor portion 21. It may be preferable for the sheet base material 91 to have appropriate insulating properties required as a raw material for the second insulating portion 90, and it is preferable for at least a portion of the sheet base material 91 to have appropriate removal properties when removing the sheet base material 91, as described below.

[0115] The thickness of the sheet substrate 91 is set so that it functions appropriately as a support when forming the first spiral conductor portion 11 and the second spiral conductor portion 21, and, if necessary, taking into consideration the insulating properties of the second insulating portion 90 derived from the sheet substrate 91 and the removal characteristics of the sheet substrate 91. Non-limiting examples include a thickness of 0.4 μm or more and 20 μm or less. The thickness of the sheet substrate 91 may be 1.0 μm or more, or 5.0 μm or more. Furthermore, to further reduce the size of the coil component 100, the thickness of the sheet substrate 91 may be 14.0 μm or less.

[0116] Examples of materials constituting the sheet substrate 91 include organic materials, inorganic materials, and composite materials thereof. Specific examples of organic materials include thermoplastic resins such as polyimide resin and polyethylene resin, thermosetting resins such as epoxy resin and phenolic resin, and cellulose. Specific examples of inorganic materials include oxide materials such as glass and alumina, metal materials such as aluminum and magnesium, and inorganic salt materials such as calcium carbonate. Specific examples of composite materials include a structure in which powder (inorganic particles) of an inorganic material is dispersed in a matrix made of an organic material.

[0117] (b) Formation of conductive layer A pattern 11CP of a third conductor portion 11C corresponding to the first conductor portion 11A is formed on one surface (surface on the Z1 side in the Z1-Z2 direction) of the prepared sheet base material 91, and a pattern 21CP of a third conductor portion 21C corresponding to the first conductor portion 21A is formed on the other surface (surface on the Z2 side in the Z1-Z2 direction) of the sheet base material 91.

[0118] The specific method for forming the pattern 11CP of the third conductor portion 11C and the pattern 21CP of the third conductor portion 21C is not limited. For example, the methods shown in FIGS. 16(b) to 17(d) are exemplified. First, as shown in FIG. 16(b), a conductive layer 55 made of the same material as the third conductor portions 11C, 14C, 21C, and 24C is formed on both surfaces of the sheet substrate 91 (on both surfaces in the Z1-Z2 direction). The method for forming the conductive layer 55 is not limited. The conductive layer 55 may be formed by a dry process such as sputtering, or by a wet process such as electroless plating. From the viewpoint of reducing the thickness of the conductive layer 55, it is preferable that the conductive layer 55 be formed by sputtering.

[0119] 16(b), a conductive layer 55H is also formed on the inner surface of the substrate through hole 91H. Note that a member having conductive layers 55 pre-formed on both sides of a sheet substrate 91, such as a copper-clad laminate, may be prepared and then substrate through hole 91H may be formed in this member. In this case, the material of the sheet substrate 91 may be exposed on the inner surface of substrate through hole 91H, or a separate process may be performed to form conductive layer 55H.

[0120] 16(c), an insulating layer 56 made of a patternable material such as a dry film resist is laminated on each of the conductive layers 55 provided on both sides of the sheet substrate 91. The thickness of the insulating layer 56 is formed to be thicker than the thickness of the first conductor portion 11A and the thickness of the first conductor portion 21A, respectively, thereby improving the shape controllability of the first conductor portion 11A and the second conductor portion 21B.

[0121] (d) Formation of the Pattern of the Third Conductor Subsequently, an exposure and development process is performed on the insulating layer 56 on both sides in the Z1-Z2 direction to remove a portion of the insulating layer 56, thereby forming a negative pattern 56P having an inverted shape of the pattern 11CP of the third conductor 11C corresponding to the first conductor 11A as the first portion and the pattern 21CP of the third conductor 21C corresponding to the first conductor 21A as the second portion. This exposes a portion of the conductive layer 55 on both sides in the Z1-Z2 direction, and forms the pattern 11CP of the third conductor 11C and the pattern 21CP of the third conductor 21C as shown in FIG. 17(d).

[0122] When exposing and developing the insulating layer 56 on both sides in the Z1-Z2 direction, by removing the portions corresponding to the third conductor portion 14C of the first draw-out portion 14 and the third conductor portion 24C of the second draw-out portion 24, the negative pattern 56P on the Z1 side in the Z1-Z2 direction can form the pattern 14CP of the third conductor portion 14C, and the negative pattern 56P on the Z2 side in the Z1-Z2 direction can form the pattern 24CP of the third conductor portion 24C. 17(d), the pattern 14CP of the third conductor portion 14C corresponding to the first conductor portion 14A is formed continuously with the pattern 11CP of the third conductor portion 11C corresponding to the first conductor portion 11A, and the pattern 24CP of the third conductor portion 24C corresponding to the first conductor portion 24A is formed continuously with the pattern 21CP of the third conductor portion 21C corresponding to the first conductor portion 21A. Hereinafter, these patterns may be collectively referred to as "third conductor portion patterns." The third conductor portion patterns have shapes corresponding to the first portion (first conductor portion 11A) and the second portion (first conductor portion 21A).

[0123] (e) Formation of First Conductor Portion After the pattern of the third conductor portion is formed in this manner, a first plating process is performed ( FIG. 17( e)). The first plating process is an electroplating process, and the processed area on the main surface of the sheet substrate 91 in the electroplating process has the pattern of the third conductor portion. Specifically, in the first plating process, electricity is passed through the conductive layers 55 provided on both sides of the sheet substrate 91 to form first conductor portions 11A and 14A, as well as first conductor portions 21A and 24A, on the pattern of the third conductor portion.

[0124] Because a negative pattern 56P formed from the insulating layer 56 is disposed around the periphery of the pattern of the third conductor portion, in the first plating process, electroplating is performed using the negative pattern 56P as a masking material, so that the first conductor portion 11A and the first conductor portion 14A are integrally formed, and the first conductor portion 21A and the first conductor portion 24A are integrally formed, corresponding to the pattern of the third conductor portion. Furthermore, in the first plating process, a via conductor portion 11H is formed as the third portion so as to fill the substrate through-hole 91H. Because this via conductor portion 11H constitutes a via portion VP, the via portion VP is formed integrally with both the first spiral conductor portion 11 and the second spiral conductor portion 21 in the first plating process step.

[0125] The plating deposit formed by electroplating is not limited as long as it has suitable conductivity. As described above, non-limiting examples include materials containing Cu, such as Cu alloys.

[0126] (f) Removal of Negative Pattern After the first conductor portions 11A, 21A and the first conductor portions 14A, 24A have been formed on both sides of the sheet base material 91 in this manner, the negative pattern 56P made of the insulating layer 56 is peeled off. As a result, as shown in FIG. 17(f), a structure is obtained in which the conductive layer 55 is positioned on the entire surface of the sheet base material 91 except for the substrate through-holes 91H, and the first conductor portions 11A, 21A and the first conductor portions 14A, 24A are arranged on the conductive layer 55. As described above, the first conductor portion 11A and the first conductor portion 21A are electrically connected by the via conductor portion 11H that constitutes the via portion VP.

[0127] (g) Removal of Conductive Layer Next, of the conductive layer 55 on the sheet base material 91, the portions exposed in the first direction (Z1-Z2 direction), specifically, the portions not covered by the first conductor portions 11A, 21A and the first conductor portions 14A, 24A, are removed. As a result, as shown in Fig. 18(g), the conductive layer 55 remaining on the sheet base material 91 becomes the third conductor portions 11C, 14C, 21C, 24C as components of the coil portion 10.

[0128] There are no limitations on the method for removing the conductive layer 55. Any process that can remove the material that constitutes the conductive layer 55 and that has little effect on the first conductors 11A, 21A and the first conductors 14A, 24A may be appropriately selected. For example, if the first conductors 11A, 21A and the first conductors 14A, 24A are made of Cu and the conductive layer 55 is made of Ni, it is possible to etch with high selectivity the portions of the conductive layer 55 that are not covered by the first conductors 11A, 21A and the first conductors 14A, 24A. In addition, if the constituent material of the conductive layer 55 is the same as that of the first conductor portions 11A, 21A and the first conductor portions 14A, 24A, the first conductor portions 11A, 21A and the first conductor portions 14A, 24A will also be partially removed by a process capable of removing the material constituting the conductive layer 55, and the shape of the electroplating deposit formed in the first plating process can be designed to take this removed portion into account.

[0129] (h) Removal of Sheet Base Material Next, a removal process is performed to remove at least a portion of a first opposing portion of the sheet base material 91, where the surface (the surface on the Z2 side in the Z1-Z2 direction) of the first portion (first conductor portion 11A) faces the second portion (first conductor portion 21A) proximal to the first portion (first conductor portion 11A), and a second opposing portion of the second portion (first conductor portion 21A) faces the surface (the surface on the Z2 side in the Z1-Z2 direction) of the second portion (first conductor portion 21A) proximal to the first portion (first conductor portion 11A). In FIG. 18(h), all of the first opposing portion and all of the second opposing portion of the sheet base material 91 have been removed. The specific method of the removal process of the sheet base material 91 is appropriately determined depending on the constituent material of the sheet base material 91. The removal process is broadly divided into dry processes such as plasma etching and wet processes such as wet etching. From the viewpoint of properly removing the sheet substrate 91 located between the components constituting the first spiral conductor 11 (the first conductor 11A and the third conductor 11C) and the components constituting the second spiral conductor 21 (the first conductor 21A and the third conductor 21C), wet etching, which is an isotropic removal process, may be preferable. The removal process may remove a portion of the sheet substrate 91, leaving a remaining portion unremoved. For example, if the sheet substrate 91 is made of a composite material of an organic material and an inorganic material, the organic material may be partially removed during the removal process. In this manner, the insulating material constituting the sheet substrate 91 may partially remain, and the remaining insulating material forms the second insulating portion 90 and insulating particles 95. By forming the second conductors 11B and 21B (described below) while the insulating material remains, a structure such as that shown in FIG. 15 is obtained.

[0130] (i) Formation of Second Conductor Portion By removing the sheet base material 91 as described above, not only the first conductor portions 11A, 14A, 21A, and 24A but also the third conductor portions 11C, 14C, 21C, and 24C are exposed. In this state, a second plating process is performed to form second conductor portions 11B and 21B on the surfaces of the first conductor portions 11A and 21A and the third conductor portions 11C and 21C, and to form second conductor portions 14B and 24B on the surfaces of the first conductor portions 14A and 24A and the third conductor portions 14C and 24C. The plating process in the second plating process step may be electroplating (electrolytic plating) or electroless plating.

[0131] 18(i), the second plating process forms the first spiral conductor 11 by providing the second conductor 11B around the first conductor 11A and the third conductor 11C, and the second spiral conductor 21 by providing the second conductor 21B around the first conductor 21A and the third conductor 21C. The first lead-out portion 14 is formed by providing the second conductor 14B around the first conductor 14A and the third conductor 14C, and the second lead-out portion 24 is formed by providing the second conductor 24B around the first conductor 24A and the third conductor 24C. At this time, a continuous portion is formed between the intersecting outer surfaces of the second conductors 11B, 21B, 14B, and 24B, forming a smooth corner. This makes it easier to form the first insulating portion 80 that will be formed later, and also makes it less likely to peel off even if it comes into contact with the constituent material of the main body portion 30, such as magnetic powder.

[0132] (j) Formation of Second Insulating Portion After the second conductor portions 11B, 21B, 14B, and 24B are thus formed by the second plating process, a first insulating portion 80 made of an insulating material is formed so as to cover at least a portion of the exposed portion of the coil conductor portion 20. In FIG. 19( j), the first insulating portion 80 is provided on the exposed surfaces of the first spiral conductor portion 11 and the second spiral conductor portion 21 constituting the coil conductor portion 20 (both of which are composed of the second conductor portions 11B and 21B), as well as on the exposed surface of the first lead portion 14 other than the surface facing the X1-X2 direction (composed of the second conductor portion 14B) and the exposed surface of the second lead portion 24 other than the surface facing the X1-X2 direction (composed of the second conductor portion 24B). External electrodes (first external electrode 41 and second external electrode 42) are provided on the surfaces not provided with the first insulating portion 80.

[0133] The formation process of the first insulating portion 80 is set appropriately depending on the constituent material of the first insulating portion 80. For example, when the first insulating portion 80 is made of a paraxylylene-based polymer, it is formed by a dry process (CVD). When the first insulating portion 80 contains a curable resin material such as an epoxy resin, it can be formed by adhering a powder or liquid containing the constituent material of the first insulating portion 80 to the exposed surface and then solidifying the adhering material by heating or the like.

[0134] (k) Formation of Main Body After the coil 10 has been formed by the above steps, the next step is to seal a portion of the first lead 14 and the second lead 24 of the coil 10 (specifically, in this embodiment, the portions other than the first lead end surface 14E and the second lead end surface 24E) with a material containing magnetic powder to form the main body 30, as shown in FIG. 19(k). The method for forming the main body 30 is not limited, and a molding process is exemplified. Specific examples of the molding process include placing the product shown in FIG. 19(j) in a mold and forming it by compression molding a material containing magnetic powder, or transfer molding a material containing magnetic powder or a raw material for that material.

[0135] There is no limitation on the method for forming the main body 30 so that the first lead-portion end face 14E and the second lead-portion end face 24E are exposed from the main body 30. For example, the main body 30 may be formed after masking the first lead-portion end face 14E and the second lead-portion end face 24E. Alternatively, the main body 30 may be formed by providing a dummy member in advance so as to cover or integrally connect the first lead-portion end face 14E and the second lead-portion end face 24E, forming the first insulating portion 80 on the surface of the dummy member, and then forming the main body 30 and cutting the dummy member to expose the first lead-portion end face 14E and the second lead-portion end face 24E.

[0136] (l) Formation of the Exterior Coating Next, an exterior coating 50 is applied to a portion of the exposed portion of the main body 30, i.e., in FIG. 20(l), the upper surface (the surface on the Z1 side in the Z1-Z2 direction) and the lower surface (the surface on the Z2 side in the Z1-Z2 direction) of the main body 30 where neither the first external electrode 41 nor the second external electrode 42 is formed, to protect the main body 30. The main body 30 may be left as is, but if an external force is applied due to a collision with another component, the insulating coating on the surface of the magnetic powder constituting the main body 30 may be scraped off, reducing the surface resistance of the main body 30. Because a reduction in surface insulation may reduce the reliability of the coil component 100, it is preferable to provide an exterior coating 50 made of an insulating material. The method for forming the exterior coating 50 is not limited. Known methods such as printing and coating may be used. The exterior coating 50 may be made of a known material, such as epoxy resin. From the perspective of improving impact resistance, a composite material in which an inorganic material, such as glass fiber, is dispersed in an organic material, such as epoxy resin, may be preferable. Furthermore, the exterior coating 50 may be formed not only to improve insulation reliability and impact resistance, but also to improve appearance quality and the positional accuracy of the external electrodes to be formed in the next step (for example, to prevent plating elongation). The exterior coating 60 may be formed simultaneously with the formation of the exterior coating 50, or may be formed by a separate process.

[0137] (m) Formation of External Electrodes Finally, one of the two terminals (first external electrode 41) is electrically connected to a portion (first external electrode end surface 14E) of the first lead portion 14 that was not sealed with the material containing magnetic powder when the main body 30 was formed, and the other of the two terminals (second external electrode 42) is electrically connected to a portion (and second external electrode end surface 24E) of the second lead portion 24. The method for forming the first external electrode 41 and the second external electrode 42 is not limited, and examples include plating and printing processes. In FIG. 20(m), the first external electrode 41 and the second external electrode 42 are formed so as to extend not only to the side surfaces (surfaces facing the X1-X2 direction) of the main body 30 but also to a portion of the bottom surface (surface on the Z2 side in the Z1-Z2 direction) of the main body 30. As described above, by forming the external electrodes (first external electrode 41 and second external electrode 42) after forming the exterior coating 50, it is possible to prevent problems (plating elongation) such as reduced shape accuracy of the external electrodes and increased risk of short-circuiting of the external electrodes due to plating deposits being formed in unexpected areas of the exposed surface of the main body 30. From this perspective, it is preferable that the exterior coating 50 is also formed on the lower surface (Z2 side in the Z1-Z2 direction), which will be the mounting surface, in the process of forming the exterior coating, as in this embodiment.

[0138] (Electronic / Electrical Device) An electronic / electrical device according to one embodiment of the present invention is an electronic / electrical device in which the coil component 100 according to one embodiment of the present invention described above is mounted, and the coil component 100 is connected to a substrate at the first external electrode 41 and the second external electrode 42. The electronic / electrical device according to one embodiment of the present invention is easily miniaturized because it is mounted with the coil component 100 according to one embodiment of the present invention. Furthermore, even if a large current is passed through the device or a high frequency is applied, malfunctions caused by deterioration in the function of the coil component 100 or heat generation are unlikely to occur.

[0139] The above-described embodiments and examples are provided to facilitate understanding of the present invention and are not intended to limit the present invention. Therefore, the elements disclosed in the above embodiments are intended to include all design modifications and equivalents within the technical scope of the present invention. For example, in the above manufacturing method, a process for removing the third conductor portions 11C, 21C, 14C, and 24C may be performed between the process for removing the sheet base material 91 shown in FIG. 18(h) and the second plating process shown in FIG. 18(i). This process may be the same process as the process for removing the conductive layer 55 shown in FIG. 18(g). As a result, the coil conductor portion 20 does not have the third conductor portions 11C, 21C, 14C, and 24C.

[0140] 100: Coil component 10: Coil portion 11: First spiral conductor portion 11A, 14A, 21A, 24A: First conductor portion 11B, 14B, 21B, 24B: Second conductor portion 11C, 14C, 21C, 24C: Third conductor portion 11CP, 14CP, 21CP, 24CP: Pattern 11F: First end portion 11FA: First opposite portion 11FS, 11GS, 11SS: Surface 11G: First corner portion 11H: Via conductor portion 12, 22: Inner peripheral end portion 13, 23: Outer peripheral end portion 14: First lead portion 14E: First lead portion end surface 14P: First extension portion 20 : Coil conductor portion 21 : Second spiral conductor portion 21F : Second end portion 21FA : Second opposite portion 21G : Second corner portion 24 : Second lead portion 24E : Second lead portion end surface 30 : Main body portion 41 : First external electrode 41a, 42a : Side portion 41b, 42b : Bottom surface portion 42 : Second external electrode 50, 60 : Exterior coating 55, 55H : Conductive layer 56 : Insulating layer 56P : Negative pattern 80, 811o, 812i, 821o, 822i : First insulating portion 80b : Boundary surface 80d : Recess 80f : Fusion portion 80i : Interposition portion 80p : Pore 80t : Thin portion 90: Second insulating portion 91: Sheet substrate 91H: Substrate through-hole 95: Insulating particle 111: First inner circumferential turn 112: First central turn 113: First outer circumferential turn 201: First coil conductor portion 211: Second inner circumferential turn 212: Second central turn 213: Second outer circumferential turn 801: First connecting portion 802: Second connecting portion 803: Third connecting portion 811f, 812f, 821f, 822f: Opposing contact portion Dt: Thickness of thin portion IF1: Interface L1: Bisector O: Axis P: Center R: Radius VP: Via portion

Claims

1. A coil component comprising a first spiral conductor portion and a second spiral conductor portion, both of which have a spiral shape when viewed in a first direction and are aligned in the first direction, and a via portion electrically connecting an inner peripheral end of the first spiral conductor portion and an inner peripheral end of the second spiral conductor portion, the coil conductor portion having a conductive path from an outer peripheral end of the first spiral conductor portion to an outer peripheral end of the second spiral conductor portion via the via portion, the coil conductor portion comprising: a first conductor portion extending along the conductive path and made of a first conductive material; and a second conductor portion made of a second conductive material and covering at least a portion of the first conductor portion, the second conductor portion being provided on at least a part of a first end of the first spiral conductor portion on a side facing the second spiral conductor portion.

2. A coil component as described in claim 1, wherein at least a portion of the turns of the first spiral conductor portion have a first corner portion that connects the face of the first end portion and a side surface along the first direction with a continuous surface.

3. A coil component as described in claim 2, wherein in a first cross section obtained by cutting along a plane passing through said first corner along said first direction, a cross section line drawn by said first corner has a shape that approximates a circular arc having a larger radius of curvature than the cross section line drawn in said first cross section at an interface between said second conductor portion and a portion made of a conductive material located inside said second conductor portion.

4. A coil component as described in claim 1, further comprising a third conductor portion made of a third conductive material between the second conductor portion provided at the first end portion and the first conductor portion which the second conductor portion covers.

5. A coil component as described in claim 1, wherein the second conductor portion is provided on at least a portion of a second end portion of the second spiral conductor portion on a side facing the first spiral conductor portion.

6. A coil component as described in claim 5, wherein at least a portion of the turns of said second spiral conductor portion have a second corner portion that connects, with a continuous surface, the surface of said second end portion and a side surface along said first direction.

7. A coil component as described in claim 6, wherein in a second cross section obtained by cutting along a plane passing through said second corner and aligned in said first direction, a cross section line drawn by said second corner has a shape that approximates a circular arc having a larger radius of curvature than the cross section line drawn by an interface between said second conductor and a portion made of a conductive material located inside said second conductor.

8. A coil component as described in claim 5, further comprising a third conductor portion made of a third conductive material between the second conductor portion provided at the second end portion and the first conductor portion which the second conductor portion covers.

9. A coil component as described in claim 1, wherein at least one of the first spiral conductor portion and the second spiral conductor portion has two turns aligned in a direction intersecting the first direction, and is provided with a first insulating portion covering at least a portion of two opposing side surfaces of the two turns.

10. A coil component as described in claim 9, wherein the first insulating portion has a portion contacting one of the two turns, a portion contacting the other of the two turns, and a first connection portion connected to these portions and extending in a direction intersecting the first direction, and the first connection portion has a thin portion that is thinner in the first direction than a portion of the first insulating portion that contacts either of the two turns.

11. A coil component as described in claim 9, wherein the first insulating portion has an intervening portion located between a turn of the first spiral conductor portion and a turn of the second spiral conductor portion, and the intervening portion has at least one of a boundary surface and an air hole.

12. The coil component according to claim 9, wherein the first insulating portion is present so as to cover each of the two opposing side surfaces of the two turns, and at least one of a line boundary and a closed space is present between the first insulating portions.

13. A coil component as described in claim 9, wherein a second insulating portion made of a material different from that constituting the first insulating portion is located at least partially between the first spiral conductor portion and the second spiral conductor portion.

14. A coil component as described in claim 13, further comprising a third conductor portion made of a third conductive material between the second conductor portion provided at the first end portion and the first conductor portion that the second conductor portion covers.

15. A coil component described in any one of claims 1 to 14, further comprising: a main body portion containing magnetic powder and covering all parts of the coil conductor portion except for the two ends; and external electrodes provided on the main body portion and electrically connected to the two ends of the coil conductor portion exposed from the main body portion.

16. An electronic or electrical device in which the coil component according to claim 15 is mounted, said coil component being connected to a substrate via said external electrodes.

17. A method for manufacturing a coil component comprising a coil conductor portion having a first spiral conductor portion and a second spiral conductor portion, both of which have a spiral shape when viewed in a first direction and are aligned in the first direction, and a via portion electrically connecting an inner peripheral end of the first spiral conductor portion and an inner peripheral end of the second spiral conductor portion, the coil conductor portion having a conductive path from an outer peripheral end of the first spiral conductor portion to an outer peripheral end of the second spiral conductor portion via the via portion, the coil conductor portion having a first conductor portion extending along the conductive path and made of a first conductive material, and a second conductor portion made of a second conductive material and covering at least a part of the first conductor portion, the first conductor portion having a first portion corresponding to the first spiral conductor portion, a second portion corresponding to the second spiral conductor portion, and a third portion corresponding to the via portion, the method comprising the steps of: forming the first portion on one side of a main surface of an insulating sheet substrate having a through hole, forming the second portion on the other side of the main surface of the sheet substrate, and forming the third portion inside the through hole; a first conductor portion formed on the sheet base material such that the first conductor portion faces an exposed portion of a member made of a conductive material, the first conductor portion being formed on the sheet base material such that the second conductor portion faces an exposed portion of the member made of a conductive material, the second ....

18. The method for manufacturing a coil component according to claim 17, wherein the second conductor portion is formed by plating.

19. A method for manufacturing a coil component as described in claim 18, wherein the main surface of the sheet substrate has a third conductor portion made of a third conductive material, the first conductor portion is formed by an electroplating process in which an electric current is passed through the third conductor portion, and the exposed portion in which the second conductor portion is formed has a portion made of the third conductor portion.

20. A method for manufacturing a coil component as described in claim 19, wherein a processing area of ​​the main surface of the sheet substrate in the electroplating process includes a negative pattern of an insulating layer formed on the third conductor portion, and before removing the sheet substrate, portions of the insulating layer and the third conductor portion that do not contact the first conductor portion are removed.

21. The method of manufacturing a coil component according to claim 20, wherein the third conductive material has etching characteristics different from those of the first conductive material.

22. A method for manufacturing a coil component as described in claim 19, wherein the treated area of ​​the main surface of the sheet substrate in the electroplating process includes a pattern of the third conductor portion having a shape corresponding to the first portion and the second portion.

23. The method for manufacturing a coil component according to claim 17, wherein the insulating material constituting the sheet base material remains at least partially between the first portion and the second portion.

24. The method for manufacturing a coil component according to claim 23, wherein the insulating material has a portion in contact with the first portion and the second portion.

25. A method for manufacturing a coil component as described in claim 23, wherein the sheet base material has a structure in which inorganic particles are dispersed in a matrix portion made of an organic material, and the insulating material contains the inorganic particles.

26. The method of manufacturing a coil component according to claim 17, further comprising forming a first insulating portion so as to cover at least a portion of the second conductor portion.

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